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11098918 | Development of a miniature scintillation camera using an NaI(Tl) scintillator and PSPMT for scintimammography. | We have developed a small scintillation camera dedicated to breast imaging and have evaluated the performance of the system. In order to increase the limited field of view (FOV) determined by the size of a position-sensitive photomultiplier tube (PSPMT), the imaging characteristics of a diverging hole collimator (DHC) were also investigated. The small scintillation camera system consists of an NaI(Tl) crystal (60 mm x 60 mm x 6 mm) coupled to a Hamamatsu R3941 PSPMT, a resistor chain circuit, preamplifiers, nuclear instrument modules, an analogue to digital converter and a PC for control and display. The intrinsic energy resolution of the system was 12.9% FWHM at 140 keV. The spatial resolution was measured using a line-slit mask and 99mTc point sources and was 3.1 mm FWHM. The intrinsic sensitivity of the system was approximately 162 counts/s kBq(-1). The DHC made it possible to image a larger FOV (75 x 75 mm2 at the surface of collimator) than a parallel-hole collimator (60 x 60 mm2). The system sensitivity obtained using the DHC gradually decreased with distance (3% at 1 cm, 6% at 2 cm and 9% at 3 cm). The results demonstrate that the system developed in this study could be utilized clinically to image malignant breast tumours. A DHC can be employed to expand the FOV of the system confined by the size of PSPMT with a promise in the performance of the system. |
11098919 | Analytic method based on identification of ellipse parameters for scanner calibration in cone-beam tomography. | This paper is about calibration of cone-beam (CB) scanners for both puted tomography and single-photon puted tomography. Scanner calibration refers here to the estimation of a set of parameters which fully describe the geometry of data acquisition. Such parameters are needed for the tomographic reconstruction step. The discussion is limited to the usual case where the cone vertex and planar detector move along a circular path relative to the object. It is also assumed that the detector does not have spatial distortions. We propose a new method which requires a small set of measurements of a simple calibration object consisting of two spherical objects, that can be considered as 'point' objects. This object traces two ellipses on the detector and from the parametric description of these ellipses, the calibration geometry can be determined analytically using explicit formulae. The method is robust and easy to implement. However, it is not fully general as it is assumed that the detector is parallel to the rotation axis of the scanner. Implementation details are given for an experimental x-ray CB scanner. |
11098920 | Blood irradiation with accelerator produced electron beams. | Blood and blood products are irradiated with gamma rays to reduce the risk of graft versus host disease (GVHD). A simple technique using electron beams produced by a medical linear accelerator has been studied to evaluate irradiation of blood and blood products. Variations in applied doses for a single field 20 MeV electron beam are measured in a phantom study. Doses have been verified with ionization chambers mercial diode detectors. Results show that the blood product volume can be given a relatively homogeneous dose to within 6% using 20 MeV electrons without the need to rotate the blood bags or the beam entry point. The irradiation process takes approximately 6.5 minutes for 30 Gy applied dose plete as opposed to 12 minutes for a dual field x-ray field irradiation at our centre. Electron beams can be used to satisfactorily irradiate blood and blood products in a minimal amount of time. |
11098921 | Verification of lung dose in an anthropomorphic phantom calculated by the collapsed cone convolution method. | Verification of calculated lung dose in an anthropomorphic phantom is performed using two dosimetry media. Dosimetry plicated by factors such as variations in density at slice interfaces and appropriate position on CT scanning slice to modate these factors. Dose in lung for a 6 MV and 10 MV anterior-posterior field was calculated with a collapsed cone convolution method using an ADAC Pinnacle, 3D planning system. Up to 5% variations between doses calculated at the centre and near the edge of the 2 cm phantom slice positioned at the beam central axis were seen, due to position of each phantom slice. Validation of dose was performed with LiF thermoluminescent dosimeters (TLDs) and X-Omat V radiographic film. Both dosimetry media produced dose results which agreed closely with calculated results nearest their physical positioning in the phantom. The collapsed cone convolution method accurately calculates dose within inhomogeneous lung regions at 6 MV and 10 MV x-ray energy. |
11098922 | Potential application of PET in quality assurance of proton therapy. | Our investigation supporting the feasibility of in situ PET monitoring in proton therapy is presented. We simulated by means of the FLUKA code the number and the spatial distribution of the main beta+ emitters created in PMMA targets by protons at typical therapeutic energies. The parison with the activation induced by 12C ions of energies corresponding to the same range shows that the available signal at the same physical dose level should be up to twice as intense for protons than that actually successfully used for the control of carbon ion therapy at GSI Darmstadt. The spatial correlation between the activity and the dose profile for protons is poorer than for 12C nuclei. However, an important check of the particle range, dose localization and stability of the treatment during all the fractions seems to be possible. |
11098923 | Hydrodynamic effects on the solute transport across endothelial pores and hepatocyte membranes. | In this short note we propose a simple and rapid procedure to calculate the net quantity of metabolites absorbed by hepatocytes from blood plasma. The blood movement through sinusoids determines an opposed circulation of plasma through the space of Disse. Hydrodynamic considerations lead to the conclusion that hepatocytes absorb for their own synthesis processes a quantity of metabolites in a volume flow of the order of 10(-12) nl s(-1) through a sieve plate surface with an area of 1 microm2. At pathological temperature (40 degrees C), the excess of the net absorbed volume flow for the entire sinusoidal surface of the mammalian liver may be as high as 1.9 nl s(-1). Some observations on the effect of red and white blood cells on the chylomicron traffic through endothelial pores are made. |
11098924 | Comparison of correction techniques for simultaneous 201Tl/99mTc myocardial perfusion SPECT imaging: a dog study. | pared two correction methods for simultaneous 201Tl/99mTc dual-isotope single-photon puted tomography (SPECT). Both approaches use the information from the third energy window placed between the photopeak windows of the 201Tl and 99mTc. The first approach, described by Moore et al, corrects only for the contribution of the 99mTc to the 201Tl primary 70 keV window. We developed the three-window transformation dual isotope correction method, which is a simultaneous cross-talk correction. The two correction methods pared in a simultaneous 201Tl/99mTc sestamibi cardiac dog study. Three separate acquisitions were performed in this dog study: two single-isotope and one dual-isotope acquisition. The 201Tl single-isotope images were used as references. The total number of counts, and the contrast between the left ventricular cavity (LVC) and the myocardium, were used in 70 keV short axis slices as parameters for evaluating the results of the dual-isotope correction methods. Three consecutive short-axis slices were used to calculate averaged contrast and the averaged total number of counts. The total number of the counts was 667000+/-500 and 414500+/-400 counts for the dual isotope (201Tl+/-99mTc) and single-isotope (201Tl-only) 70 keV images, respectively. The corrected dual-isotope images had 514700+/-700 and 368000+/-600 counts for Moore's correction and our approach, respectively. Moore's method improved contrast in the dual isotope 70 keV image to 0.14+/-0.03 from 0.11+/-0.02, which was the value in the 70 keV non-corrected dual-isotope image. Our method improved the same contrast to 0.22+/-0.03. The contrast in the 201Tl single-isotope 70 keV image was 0.28+/-0.02. Both methods improved the 70 keV dual-isotope images. However, our approach provided slightly better images than Moore's correction pared with 201Tl-only 70 keV images. |
11098928 | Encapsulating peritoneal sclerosis: definition, etiology, diagnosis, and treatment. International Society for Peritoneal Dialysis Ad Hoc Committee on Ultrafiltration Management in Peritoneal Dialysis. | Current definitions of encapsulating peritoneal sclerosis are practical and clinically relevant. It is important to adhere to a more uniform use of the proper terminology, and it is the mendation of the authors that EPS be adopted as the more appropriate term. The best literal definition of EPS is based on clinical-pathologic criteria. Differentiation of EPS from the general category of ultrafiltration failure is required. Further, better appreciation of the diverse pathways that can lead to the same mon clinical-pathologic picture should not be overshadowed by the requirement of uniform terminology. Incidence and prevalence of the syndrome have been defined in some large populations and a few single-center experiences. The former show an incidence of less than 1%, while higher percentages are reported in the latter. The reported increased incidence with duration on therapy requires validation. The epidemiology of the syndrome offers limited insight into its pathogenesis. A list of factors, both dialysis-related and non dialysis-related. has been accumulated. Except in a few categories where agents are clearly related to the development of EPS, the majority of the listed factors for dialysis-related BPS remain, at best, associations and at worst, simple conjecture. The same limitations that plague the issue of etiology apply in the area of pathogenesis. More basic, focused work is required. The diagnosis of EPS remains based on clinical suspicion confirmed with, primarily, radiologic findings. Pathologic confirmation is obtained in cases e to surgery for management or for catheter removal. Radiologic studies are precise enough for confirmation, but none have been evaluated for early diagnosis for possible early intervention or prevention. Studies based on transport characteristics or effluent dialysate constituents are not useful for EPS. At present, there are no reliable predictive tests for BPS that can be used in individual patients. Therapy of BPS is based on anecdotal evidence. The possible variable etiologies and probable distinct pathways leading to the syndrome may make a uniform therapeutic approach unlikely. Further, the limited number of cases and the sporadic pattern of occurrences make therapeutic trials not readily feasible. This is distinct from the case of ultrafiltration failure, where significant advances in mechanism elucidation and rationale-based interventions have been made. |
11098929 | Diversity is demonstrated in class I HLA-A and HLA-B alleles in Cameroon, Africa: description of HLA-A*03012, *2612, *3006 and HLA-B*1403, *4016, *4703. | To examine the genetic diversity in west Africa, class I HLA-A and HLA-B alleles of 92 unrelated individuals from two areas in the Cameroon, the capital Yaoundé and the village of Etoa, were identified by direct automated DNA sequencing of exons 2 and 3 of the HLA-B locus alleles and sequence-specific oligonucleotide probe (SSOP) and/or sequencing of the HLA-A locus alleles. HLA-A*2301 (18.7%), A*2902 (10.4%), B*5301 (10.9%), and B*5802 (10.9%) were the most frequently detected alleles, present in at least 10% of the population. A total of 30 HLA-A locus and 33 HLA-B locus alleles, including six novel alleles, were detected. The novel alleles were HLA-A*03012, A*2612, A*3006 and HLA-B*1403, B*4016, and B*4703. HLA-B*4703 contains a novel amino acid sequence that is bination of the first 5 amino acids of the Bw6 epitope and the last 2 residues of the Bw4 epitope. The addition of 6 alleles to the ever-expanding number of known class I HLA alleles supports our hypothesis that extensive genetic diversity, including previously undescribed alleles, would be observed in this African population. In the Yaoundé population, the allele frequency distribution at the HLA-A locus is consistent with distributions indicative of balancing selection. Extensive HLA-A-B haplotypes were observed in this population suggesting that only a fraction of the Cameroon HLA-A-B haplotype diversity has been observed. |
11098930 | The molecular determination of HLA-Cw alleles in the Mandenka (West Africa) reveals a close genetic relationship between Africans and Europeans. | HLA-Cw alleles were determined by high-resolution polymerase chain reaction-sequence-specific oligonucleotide probe (PCR-SSOP) oligotyping in a sample of 165 Mandenka, a population from Eastern Senegal previously analysed for A/B and DRB/DQB polymorphisms. A total of 18 Cw alleles were identified, with Cw*0401/5 and 1601 accounting for bined frequency of 36%. parison of Cw allele frequencies among several populations of different origins, Mandenka, Swiss, English, Ashkenazi Jews from the UK and Japanese, reveals a high genetic heterogeneity among them, but also a much closer relationship between Mandenka, Europeans and Ashkenazi than between any of these populations and Japanese. Cw*0501, Cw*0701 and Cw*1601, among others, appear to be restricted to the European and African populations. Many B-Cw haplotypes exhibit a significant linkage disequilibrium in the Mandenka, among which B*3501-Cw*0401 and B*7801-Cw*1601, formed by the most frequent B and Cw alleles, and B*5201-Cw*1601, B*5702-Cw*18 and B*4410-Cw*0401, not yet observed in other populations. B*3501-Cw*0401 is found with similar frequencies in Europeans. The results possibly support a close historical relationship between Africans and Europeans pared to East Asiatics. However, the HLA-Cw frequency distributions are characterised by an excess of heterozygotes, indicating that balancing selection may have played a role in the evolution of this polymorphism. |
11098931 | Development of a PCR-SSOP approach capable of defining the natural killer cell inhibitory receptor (KIR) gene sequence repertoires. | A molecular typing method based on polymerase chain reaction (PCR) amplification of three different target domains (immunoglobulin domains 1 and 3, and the transmembrane-cytoplasmic domain), followed by hybridisation with 26 digoxigenin-labelled sequence-specific oligonucleotide probes (SSOP) has been established for the polymorphic killer inhibitory receptor (KIR) genes. In addition to identifying the 12 KIR subfamilies, our PCR-SSOP typing approach could also distinguish the putative alleles, NKB1 and NKAT3, prise the KIR3DL1 subfamily. Ninety unrelated blood donors and 13 families (52 individuals), including both parents, were subjected to our KIR PCR-SSOP typing approach. All 12 KIR subfamilies, including a 2DS5 variant sequence, were present in the 90 individuals and displayed varied phenotype frequencies: 2DL1 (0.96), 2DL2 (0.31), 2DL3 (0.95), 2DS1 (0.56) 2DS2 (0.51), 2DS3 (0.27), 2DS4 (0.96), 2DS5v (0.35), 3DS1 (0.47), 3DL1 (0.96), 3DL2 (1.0) and 2DL4 (1.0). A total of 23 different KIR phenotypes were defined in this study, and 10 of these were only found on one occasion in one individual, indicating considerable diversity in the KIR phenotype profiles within the Irish population. Most individuals (93%) possessed plement of inhibitory KIR specificities for the three well-defined HLA-B and -C ligands. An unusual probe pattern for 3DS1 was observed in 3 individuals indicating a variant 3DS1 gene sequence with changes at nucleotide positions 1185-1186, within the cytoplasmic domain. Sequencing analysis revealed a new single nucleotide polymorphism in exon 3 of 3DL1 NKB1(195, G-A) and a 22-bp deletion polymorphism in exon 5 of 2DS4 (nucleotides 777-798 deleted). A number of strong KIR associations were observed, namely 2DL1 with 2DL3, 2DS4 with 3DL1, 2DL2 with 2DS1/2DS2/2DS3, 2DS1 with 2DS3/2DS5v/3DS1, 2DS2 with 2DS3 and 2DS5v with 3DS1. Analysis of the KIR segregation observed in the 13 families confirmed these strong associations and permitted the definition of a number of partial KIR haplotypes, e.g. 2DL2-2DS1-2DS2-2DS3-3DL1. The segregation analysis concluded that at least 3 distinct gene loci encode 2DL1-4 and at least 4 gene loci encode the non-inhibitory KIR2DS1-2DS5. In the case of 3DL1-2 and 3DS1, our data suggests 3 gene loci, one for each subfamily. |
11098933 | HLA class II alleles in Japanese patients with immune thrombocytopenic purpura. Associations with anti-platelet glycoprotein autoantibodies and responses to splenectomy. | HLA class II alleles and immunoglobulin allotypes were determined in 83 Japanese patients with immune thrombocytopenic purpura (ITP) and 114 race-matched healthy controls. Distribution of DRB and DQB1 alleles as well as G1M(f, z), G2M(n+, n-), and KM(1, (1,2), 3) were not different between ITP patients and healthy controls, while DPB1*0201 was marginally increased in ITP patients vs. healthy controls (51% vs. 28%, Pc= 0.04, OR=2.6 [1.4-4.8]). In contrast, strong associations between anti-glycoprotein autoantibodies and HLA class II genes were found as follows: antiGPIIb-IIIa antibody with DRB1*0405 and DQB1*0401; and anti-GPIb-IX antibody with DRB1*0803 and DQB1*0601. When factors influencing therapeutic responses to splenectomy were examined, a poor response was correlated with the presence of DRB1*0405, DQB1*0401 and anti-GPIIb-IIIa antibody (P=0.01, 0.002, and 0.03, respectively). Our results indicate that HLA class II genes influence the production of anti-glycoprotein antibody specificities rather than the development of ITP. In addition, HLA class II genotyping could be useful in predicting therapeutic responses to splenectomy in Japanese patients with ITP. |
11098934 | Screening for the IDDM high-risk genotype. A rapid microtitre plate method using serum as source of DNA. | Norwegian babies born with the HLA-DRB1*0401-DQA1*03-DQB1*0302/DRB1*03-DQA1+ ++*05-DQB1*0201 genotype have an estimated 17% lifetime risk of developing insulin-dependent diabetes mellitus (IDDM). Identifying these children is important for future prevention, and for studies of the non-genetic factors involved in IDDM. The aim of the study was to develop a rapid screening method for this high-risk genotype. DNA was extracted from serum collected during routine newborn screening for phenylketonuria and hypothyreosis. The second exons of HLA-DQA1 and DQB1 were co-amplified using biotinylated primers, amplicons were hybridized to a set of seven probes immobilized on a microtitre plate using a single hybridisation temperature, and detected colorimetrically by streptavidin-HRP conjugate and tetramethylbenzidine substrate. The DRB1*04 subtyping was performed using six different probes at identical conditions. The prevalence of the DRB1*0401-DQA1*03-DQB1*0302/DRB1*03-DQA1*0 5-DQB1*0201 genotype among 1,026 Norwegian babies was 2.7% (CI 95%: 1.7-3.7%). The new high-throughput genetic screening method for IDDM risk can easily be automated and included in newborn screening programs. |
11098936 | Sequence-based typing of HLA-B: the B7 cross-reacting group. | The large number of polymorphic sites in the HLA-B locus makes sequencing an efficient way of detecting and analysing them. Most polymorphic sites are located in the alpha1 and alpha2 domains of the molecule, encoded by exons 2 and 3 of the gene. An HLA-B-specific sequence-based typing (SBT) strategy was designed for routine application identifying the polymorphic sites in these domains. Exons 2 and 3 were amplified separately using amplification primers located in intron 1, intron 2 and intron 3. Separate amplification of exons 2 and 3 resulted in short polymerase chain reacting (PCR) products and enabled a solid-phase sequencing approach, which made correct assignment of heterozygous positions possible due to low background. A one-step sequencing reaction was performed using fluorescent dye-labelled sequencing primers. One forward sequencing reaction was performed for exon 2, whereas for exon 3, two forward sequencing reactions were needed using two different sequencing primers located in intron 2 and exon 3. bined sequences of exon 2 and 3 were used for automatic alignment to an HLA-B sequence database and automatic allele assignment. A total of 355 individuals with at least one allele belonging to the B7 cross-reacting group (B7, 13, 22, 27, 40, 41, 42, 47, 48, 81 and 82) were typed for HLA-B by SBT. In the B7 group 48 different alleles were identified, in the non-B7 group a further 59 alleles were sequenced, 9 new alleles were identified. The sequencing strategy described has proven to be reliable and efficient for high-resolution HLA-B typing. |
11098935 | The CTLA4/CD28 gene region on chromosome 2q33 confers susceptibility to celiac disease in a way possibly distinct from that of type 1 diabetes and other chronic inflammatory disorders. | The effect of the gene region on chromosome 2q33 containing the CD28 and the cytotoxic T-lymphocyte associated (CTLA4) genes has been investigated in several diseases with chronic inflammatory nature. In addition to celiac disease (CD), type I diabetes, Grave's disease, rheumatoid arthritis and multiple sclerosis have all demonstrated associations to the A/G single nucleotide polymorphism (SNP) in exon 1, position +49 of the CTLA4 gene. The purpose of this study was to investigate this gene region in a genetically homogeneous population consisting of 107 Swedish and Norwegian families with CD using genetic association and linkage methods. We found a significant association with preferential transmission of the A-allele of the exon 1 +49 polymorphism by using the transmission disequilibrium test (TDT). Suggestive linkage of this region to CD was moreover demonstrated by non-parametric linkage (NPL) analysis giving a NPL-score of 2.1. These data strongly indicates that the CTLA4 region is a susceptibility region in CD. Interestingly, of the several chronic inflammatory diseases that exhibit associations to the CTLA4 +49 A/G dimorphism, CD appears to be the only disease associated to the A allele. This suggests that the +49 alleles of the CTLA4 gene are in linkage disequilibrium with two distinct disease predisposing alleles with separate effects. The peculiar association found in the gut disorder CD may possibly relate to the fact that the gastrointestinal immune system, in contrast to the rest of the immune system, aims to establish tolerance to foreign proteins. |
11098937 | Unexpected Bw4 and Bw6 reactivity patterns in new alleles. | The Bw4 and Bw6 epitopes were the first HLA-B differences to be recognized by serological methods. Since then 44 serological groups have been identified and more than 250 alleles assigned by molecular typing methods. In general each serological HLA-B group is associated with the presence of either the Bw4 or the Bw6 epitope. There are several exceptions to this rule. Four alleles, B*4601, *7301, *5503 and *1806, show no serological reactivity with either Bw4 or Bw6. Although the Bw6 motif at residues 77-83 is present in these alleles the Bw6 epitope is modified by a valine at residue 76. One or more alleles from the B8, B40 and B62 groups are identified as Bw4 positive, whereas all others are Bw6 positive. In the groups B27, B44 and B47 several alleles are found to be Bw6 positive, while the majority is Bw4 positive. patibility testing of dialysis patients and their families revealed the serological presence of an unexpected Bw4 epitope associated with B18 in one patient and B56 in another. Allele-specific amplification and sequencing of exons 2 and 3 of these HLA-B alleles revealed the presence of the Bw4 sequence motif for both. The new alleles were assigned B*1809 and B*5607, respectively. In 2 other patients the presence of a new B*07 allele was determined by sequence based typing. Although the new allele, B*0715, showed the Bw6 sequence motif at positions 77 to 83, a substitution of amino acid 76 from glutamic acid to valine was identified. This change resulted in an aberrant Bw6 serological reaction pattern. |
11098938 | Increased diversity within the HLA-B*07 group: identification of the two novel alleles B*0709 and B*0710. | The identification of the two novel alleles, HLA-B*0709 and B*0710, is described. B*0709 differs from B*07021 by a nucleotide exchange at position 419 (A>C) which is located in exon 3. At the protein level the nucleotide exchange results in an amino acid residue difference (Tyr116Ser). The other newly detected allele, B*0710, differs from B*07021 by a nucleotide exchange at position 272 (A>G) which is located in exon 2. This nucleotide exchange also leads to an amino acid substitution (Tyr67Cys). The allogeneic potential in case of mismatch with other alleles of the B*07 group at bone marrow transplantation was assessed. The peptide motifs between B*0709 and B*0711 may be very similar and thus the alloreactive potential in case of mismatch may be low. In contrast, mismatches of B*0709 and B*0710 with other B*07 alleles are likely to stimulate alloreactive T cells. |
11098939 | Characterization of HLA-B*3921 and confirmation of HLA-B*4415, two variant HLA-B alleles identified in the Omani population. | We describe a variant HLA-B*39 allele present in two individuals from Oman, which has been officially named HLA-B*3921. In addition we confirm the existence of HLA-B*4415, an allele closely related to HLA-B*4501 differing only at the Bw4/Bw6 epitope. |
11098940 | Identification by sequencing based typing and complete coding region analysis of three new HLA class II alleles: DRB3*0210, DRB3*0211 and DQB1*0310. | The study of HLA class II polymorphism by direct exon 2 DNA sequencing analysis has been established to be a reliable and accurate high-resolution typing procedure. This approach shows some advantages in relation to previous methods, polymerase chain reaction using sequence-specific oligonucleotides (PCR-SSO) and sequence-specific primers (PCR-SSP), basically due to the capability of analysis for plete sequenced genomic region, including non-polymorphic motifs. DRB3 and DQB1 sequencing based typing (SBT) in unrelated bone marrow donor searching allowed us to detect three new alleles. plete coding region sequences were characterised from cDNA. Two new DRB3 alleles, DRB3*0210 and DRB3*0211, were described in two Caucasian bone marrow donors. Both sequences showed single point mutations regarding DRB3*0202, producing amino acid replacements at positions 51 (Asp to Thr) and 67 (Leu to Ile), respectively. These two point mutations can be found in other DRB alleles, and suggest that gene conversion would be involved in the origin of both alleles. A new DQB1 sequence was found in a Spanish patient that showed two nucleotide differences, positions 134 and 141, with regard to its close similar DQB1*03011 allele. Only substitution at position 134 provoked amino acid replacement at residue 45, Glu to Gly. This single amino acid change would be involved in the lack of serologic recognition of this new molecule by DQ7-specific reagents. |
11098941 | The carotid pulse check revisited: what if there is no pulse? | This study was undertaken to evaluate the diagnostic accuracy and time required by first responders to assess the carotid pulse in potentially pulseless patients. We conducted a prospective, randomized study of first responders (n = 206; four different training levels) and were blinded as to the patients' conditions in the cardiac operating rooms of a university hospital. Sixteen patients underwent coronary artery bypass surgery on nonpulsatile cardiopulmonary bypasses. Carotid pulse check was performed either during pulsatile (spontaneous) or during nonpulsatile (extracorporeal) circulation. Patients' hemodynamic status at the time of assessment, diagnostic accuracy of the first responders, and the time required to diagnose carotid pulsatility or pulselessness were documented. Within 10 secs, only 16.5% of the participants (34 of 206) were able to reach any decision about their patients' pulse status. Assessments that were both rapid and correct (15%, i.e., 31 of 206) occurred almost exclusively in pulsatile patients. Advanced training level shortened the delay to decision and improved its accuracy. However, merely 2% of the participants (1 of 59) correctly recognized a truly pulseless patient within 10 secs. Recognition of pulselessness of the carotid artery by rescuers with basic cardiopulmonary resuscitation training is time-consuming and highly inaccurate. Although the carotid pulse check needs to be taught, its importance in the context of layperson basic life support should be de-emphasized. |
11098942 | Cardiopulmonary resuscitation without ventilation. | Current resuscitation methods, although occasionally effective, rarely perform as well as initially anticipated. Some of the disappointment can be attributed to the difficulty of the task for many, including both professional and lay first responders. Significant attention has been paid recently to the need to simplify both the technique and the teaching of resuscitation. In considering simplification of the current resuscitation scheme, a logical start is an honest reappraisal of the importance and priorities of each of the once sacrosanct ABCs, specifically, establishment of an Airway, artificial Breathing (mouth-to-mouth breathing), and pressions for temporary Circulation. Experimental data continue to accumulate indicating that most important within this triad is circulation. Adequate oxygen exists within the blood during at least the first 10 mins of cardiac arrest. If circulation is provided to distribute such oxygen, no survival disadvantage results with pression-only basic life support (BLS) efforts. Even a totally occluded airway during the first 6 mins of cardiac arrest does promise survival if reasonable circulation is provided with pressions. Clinical studies support the same conclusion that what most influences survival in any BLS effort is circulation, not ventilation. Belgium investigators have shown equal survival rates among those treated with pressions plus ventilation and those who received pressions alone. Telephone dispatcher-guided BLS cardiopulmonary resuscitation (CPR) has likewise shown no survival disadvantage to pression-only CPR pared with telephone-guided standard BLS CPR. Based on this reasoning, a new simplified BLS method has been proposed. "Staged" CPR consists of a strategy to initially teach laypersons a simplified approach to BLS, which requires only pressions and not mouth-to-mouth breathing. "Bronze" CPR, in which pression-only BLS is taught, pared with the standard European Resuscitation Council BLS course for laypersons. Manikin "exit testing" at pletion has revealed significant advantages of the simplified pared with standard CPR courses for the lay public. |
11098943 | Dispatcher-assisted "phone" cardiopulmonary resuscitation by chest compression alone or with mouth-to-mouth ventilation. | Based on both animal studies and field studies of the process and intermediate es related to cardiopulmonary resuscitation (CPR), we initiated a randomized trial of dispatcher-assisted CPR, with the intervention arm receiving instructions for pression only and the control arm receiving standard instructions for airway maintenance ventilation, and pression. Of 241 patents randomized to pression instructions only, 35 survived pared with 29 of 279 (10.4%) patients in the control arm (p = .09). These results may have implications for future guidelines and teaching CPR. |
11098944 | Role of mouth-to-mouth rescue breathing in bystander cardiopulmonary resuscitation for asphyxial cardiac arrest. | There is increasing evidence that mouth-to-mouth rescue breathing may not be necessary during brief periods of bystander cardiopulmonary resuscitation (CPR) for ventricular fibrillation. In contrast to ventricular fibrillation cardiac arrests, it has been assumed that rescue breathing is essential for treatment of asphyxial cardiac arrests because the cardiac arrests result from inadequate ventilation. This review explores the role of mouth-to-mouth rescue breathing during bystander CPR for asphyxial cardiac arrests. Clinical data suggest that survival from apparent asphyxial cardiac arrest can occur after CPR consisting of pressions alone, without rescue breathing. Two randomized, controlled swine investigations using models of bystander CPR for asphyxial cardiac arrest establish the following: a) that prompt initiation of bystander CPR is a crucially important intervention; and b) that pressions plus mouth-to-mouth rescue breathing is markedly superior to either technique alone. One of these studies further demonstrates that early in the asphyxial pulseless arrest process doing something (mouth-to-mouth rescue breathing or pressions) is better than doing nothing. |
11098945 | Effects of inspired gas content during respiratory arrest and cardiopulmonary resuscitation. | Mouth-to-mouth and bag-valve-mask ventilation have been an indispensable part of cardiopulmonary resuscitation (CPR). However, only recently have the effects of different tidal volumes on arterial oxygenation been reported for mouth-to-mouth and bag-valve-mask ventilation. Currently mended tidal volumes (10-15 mL/kg) are associated with an increased risk of gastric inflation because they produce high peak inspiratory pressures. An animal model of ventilation with an unprotected airway showed that a smaller tidal volume (6 mL/kg) is as effective as a larger tidal volume (12 mL/kg) in maintaining Sao2 at >96%. However, a smaller tidal volume with exhaled gas ventilation produced a mean Sao2 of 48%, which is ineffective. Ventilation gas mixtures have been studied in models of cardiac arrest and CPR. One study showed that ventilation with air during 6 mins of CPR resulted in a return of spontaneous circulation in 10 of 12 pared with only 5 of 12 animals ventilated with exhaled gas (p<.04). Arterial and mixed-venous Po2 were significantly higher, and Pco2 was significantly lower in the air ventilation group. Investigations of the cardiovascular effects of mouth-to-mouth ventilation during CPR suggest that there are adverse effects during low blood flow states. However, mouth-to-mouth ventilation during respiratory arrest is lifesaving and should continue to be taught and emphasized in basic life support courses. |
11098946 | Efficacy of interposed abdominal compression-cardiopulmonary resuscitation (CPR), active compression and decompression-CPR and Lifestick CPR: basic physiology in a spreadsheet model. | This study was undertaken to understand and predict results of experimental cardiopulmonary resuscitation (CPR) techniques pression and pression of either the chest or the abdomen. Simple mathematical models of the adult human circulation were used. Assumptions of the models are limited to normal human anatomy and physiology, the definition pliance (volume change/pressure change), and Ohm's law (flow = pressure/resistance). Interposed pression-CPR, pression and pression of the chest, and Lifestick CPR, bines interposed pression and pression and pression, produce, respectively, 1.9-, 1.2-, and 2.4-fold greater blood flow than standard CPR and systemic perfusion pressures of 45, 30, and 58 mm Hg, respectively. These positive effects are explained by improved pump priming and are consequences of fundamental principles of cardiovascular physiology. |
11098947 | Cardiopulmonary resuscitation with a hydraulic-pneumatic band. | Improved blood flow during cardiopulmonary resuscitation (CPR) has been shown to enhance survival from cardiac arrest. pression with a circumferential pneumatic vest enhances blood flow, but the size, weight, and energy consumption of the inflation system limit its portability and, thereby, have made clinical studies difficult. The purpose of this investigation was to study an improved circumferential pression device that uses a constricting band that is pneumatically actuated. The constricting band applies its force to a hydraulic cushion that contacts the anterior and lateral aspects of the chest. The hydraulic cushion transfers the circumferential constriction to inward force. CPR was performed on subjects 5 mins after induction of ventricular fibrillation, with the hydraulic-pneumatic band system (HB-CPR), with a pneumatic vest system (PV-CPR), and with standard manual CPR (S-CPR), each done for 2 mins in randomized order. Aortic and right atrial pressures were measured with micromanometers. Coronary perfusion pressure was calculated as the mean difference between the aortic and right atrial pressures during the release phase of pression. Aortic pressure and coronary perfusion pressure with HB-CPR and PV-CPR were improved over S-CPR, and HB-CPR parable pressures to those of PV-CPR. The system for performing HB-CPR, however, was substantially lighter (10 vs. 50 kg) and consumed less energy (300 vs. 1000 watts) than that for PV-CPR. Thus, HB-CPR appears to produce a similar improvement in hemodynamics over S-CPR as PV-CPR but may be more portable than PV-CPR. Therefore, HB-CPR may allow larger scale testing of circumferential pression approaches. |
11098949 | Electrocardiographic waveform analysis for predicting the success of defibrillation. | A new electrocardiographic predictor of the likelihood that an electrical shock would restore a perfusing rhythm is described. The intent was to develop a prognosticator that would be displayed during pression. We anticipated that such a predictor would allow more selective timing of electrical shocks and reduce electrical injury to the myocardium caused by repetitive shocks. In a porcine model of cardiac arrest because of ventricular fibrillation, electrocardiographic recordings of ventricular fibrillation wavelets were analyzed and transformed into an amplitude spectrum area (AMSA). An AMSA value of 21 mV x Hz predicted restoration of perfusing rhythm with a positive predictive value equivalent to that of coronary perfusion pressure. More important, the negative predictive value that a shock would fail to reestablish spontaneous circulation was 96%. AMSA, therefore, has the potential for guiding optimal timing of defibrillation. |
11098951 | Electrophysiology of ventricular fibrillation and defibrillation. | The survival rate from ventricular fibrillation is very high for short-duration fibrillation (<30 secs) but decreases to approximately 3% to 30% in out-of-hospital conditions. During short-duration fibrillation, action potentials occur rapidly with no intervening period of electrical diastole; a shock defibrillates by interacting with the fibrillation action potential to produce a uniformly long postshock extension of refractoriness. In contrast, during long-duration fibrillation, ischemia-induced degradation of cellular electrophysiology occurs, which causes intervening periods of electrical diastole between fibrillation action potentials and, thus, slowing of fibrillation frequency. A successful defibrillation shock must now not only prolong refractoriness when delivered during the action potential but must also excite cells during the periods of depolarized diastole. Biphasic waveforms enhance both effects by causing premature membrane repolarization with the first pulse, thereby allowing sodium channel recovery from inactivation so that the second pulse produces better-formed responses both during the cellular action potential and during the depolarized diastole. Therefore, biphasic waveforms remain superior to monophasic waveforms for treatment of long-duration fibrillation. Improved understanding of the ischemia-induced changes in cellular electrophysiology will suggest further improvements in both defibrillator waveforms and resuscitation techniques. |
11098950 | Suspended animation for delayed resuscitation from prolonged cardiac arrest that is unresuscitable by standard cardiopulmonary-cerebral resuscitation. | Standard cardiopulmonary-cerebral resuscitation fails to achieve restoration of spontaneous circulation in approximately 50% of normovolemic sudden cardiac arrests outside hospitals and in essentially all victims of penetrating truncal trauma who exsanguinate rapidly to cardiac arrest. Among cardiopulmonary-cerebral resuscitation innovations since the 1960s, automatic external defibrillation, mild hypothermia, emergency (portable) cardiopulmonary bypass, and suspended animation have potentials for clinical breakthrough effects. Suspended animation has been suggested for presently unresuscitable conditions and consists of the rapid induction of preservation (using hypothermia with or without drugs) of viability of the brain, heart, and organism (within 5 mins of normothermic cardiac arrest no-flow), which increases the time available for transport and resuscitative surgery, followed by delayed resuscitation. Since 1988, we have developed and used novel dog models of exsanguination cardiac arrest to explore suspended animation potentials with hypothermic and pharmacologic strategies using aortic cold flush and emergency portable cardiopulmonary bypass. e evaluation was at 72 or 96 hrs after cardiac arrest. Cardiopulmonary bypass cannot be initiated rapidly. A single aortic flush of cold saline (4 degrees C) at the start of cardiac arrest rapidly induced (depending on flush volume) mild-to-deep cerebral hypothermia (35 degrees to 10 degrees C), without cardiopulmonary bypass, and preserved viability during a cardiac arrest no-flow period of up to 120 mins. In contrast, except for one antioxidant (Tempol), explorations of 14 different drugs added to the aortic flush at room temperature (24 degrees C) have thus far had disappointing e results. Profound hypothermia (10 degrees C) during 60-min cardiac arrest induced and reversed with cardiopulmonary bypass achieved survival without functional or histologic brain damage. Further plans for the systematic development of suspended animation include the following: a) aortic bining hypothermia with mechanism-specific drugs and novel fluids; b) extension of suspended animation by ultraprofound hypothermic preservation (0 degrees to 5 degrees C) with cardiopulmonary bypass; c) development of the most effective suspended animation protocol for clinical trials in trauma patients with cardiac arrest; and d) modification of suspended animation protocols for possible use in normovolemic ventricular fibrillation cardiac arrest, in which attempts to achieve restoration of spontaneous circulation by standard external cardiopulmonary resuscitation-advanced life support have failed. |
11098952 | Low-energy biphasic waveform defibrillation reduces the severity of postresuscitation myocardial dysfunction. | Both clinical and experimental studies have demonstrated substantial impairment of ventricular function after resuscitation from cardiac arrest. Indeed, postresuscitation myocardial dysfunction has been implicated as a potentially important mechanism, accounting for fatal es after successful resuscitation in 70% of victims within the first 72 hrs. Recent experimental studies implicated the total electrical energy delivered during defibrillation as an important correlate with the severity of postresuscitation myocardial dysfunction and postresuscitation survival. This prompted us to investigate the option of using lower electrical energy biphasic waveform defibrillation. pared the effects of low-energy biphasic waveform defibrillation with conventional monophasic waveform defibrillation after a short (4 mins), intermediate (7 mins), or prolonged (10 mins) interval of untreated ventricular fibrillation. Biphasic waveform defibrillation with a fixed energy of 150 joules proved to be as effective as conventional monophasic damped sine waveform defibrillation for restoration of spontaneous circulation, with significantly lower delivered energy. This was associated with significantly less severity of postresuscitation myocardial dysfunction. The low-energy biphasic waveform defibrillation is, therefore, likely to be the future direction of transthoracic defibrillation in settings of cardiopulmonary resuscitation. |
11098954 | Effects of repetitive electrical shocks on postresuscitation myocardial function. | Whereas myocardial cell injury can occur during electrical defibrillation proportional to the energy level of individual shocks, only minimal (or no) injury seems to develop when the energy is limited to the levels typically required to terminate ventricular fibrillation. During cardiac arrest, however, multiple shocks are often required to terminate ventricular fibrillation or to treat episodes that appear subsequently during the resuscitation effort or the postresuscitation interval. Concern exists because an inverse relationship has been reported between the number of electrical shocks delivered during cardiac resuscitation and both resuscitability and survival. Repetitive electrical shocks can alter diastolic function and prompt leftward shifts of the end-diastolic pressure-volume curves. Repetitive shocks may, therefore, contribute to the recently recognized phenomenon of postresuscitation myocardial dysfunction and hamper efforts to petent myocardial function after resuscitation. Thus, strategies aimed at limiting the number of electrical shocks during cardiopulmonary resuscitation are highly desirable. These may include real-time ventricular fibrillation waveform analysis to improve targeting of individual shocks and efforts (using mechanical and pharmacologic means) to render the myocardium more responsive to individual shocks and to promote greater electrical stability after successful defibrillation. |
11098953 | Experimental studies on precordial compression or defibrillation as initial interventions for ventricular fibrillation. | Countershock of prolonged ventricular fibrillation is usually followed by asystole or a nonperfusing rhythm. Data from three laboratory investigations indicate that administration of epinephrine and cardiopulmonary resuscitation (CPR) preceding countershock of prolonged ventricular fibrillation significantly improves cardiac resuscitation pared with immediate countershock (relative risk reduction of failed resuscitation, 0.61). Preliminary investigations indicate that a similar improvement is not observed when the ventricular fibrillation period is of shorter duration, e.g., 5 mins. This time interval is probably at the lower limit at which CPR preceding shock of ventricular fibrillation provides benefit in terms of cardiac resuscitation. A single clinical trial of "CPR first" supports the use of a brief period of CPR before countershock of prolonged ventricular fibrillation. Additional trials with and without epinephrine are anticipated. |
11098955 | Vasopressin and endothelin during cardiopulmonary resuscitation. | Vital organ blood flow during cardiopulmonary resuscitation (CPR) and neurologic recovery after CPR were significantly better in pigs treated with pared with epinephrine. Furthermore, two clinical studies evaluating both out-of-hospital and inhospital cardiac arrest patients found higher 24-hr survival rates in patients who were resuscitated with pared with epinephrine. Scientists at the Leopold Franzens University in Innsbruck, Austria, are currently coordinating a multicenter, randomized clinical trial under the aegis of the European Resuscitation Council to study the effects of vasopressin vs. epinephrine in out-of-hospital cardiac arrest patients. Results of anticipated 1,500 enrolled patients may be available in 2001 and may help to determine the role of vasopressin during CPR. Another new, recently studied vasopressor for CPR is endothelin-1. To date, this vasopressor has only been studied as an intervention in animal CPR models, although plasma levels have been investigated in cardiac arrest patients. Initial reports found improved coronary perfusion pressure bined with epinephrine. However, the CPR research group of the University of Arizona Sarver Heart Center found excessive vasoconstriction and worse survival than with epinephrine alone. |
11098956 | Echo-Doppler observations during cardiac arrest and cardiopulmonary resuscitation. | We describe a series of investigations that used transesophageal echo-Doppler observations during cardiac arrest and cardiopulmonary resuscitation. Regular contractions of the left atrium persisted during the initial 7 mins of untreated ventricular fibrillation. Ventricular chamber deformation and mitral valve closing and opening followed pression and relaxation. Stroke puted from differences between diastolic and systolic areas of the left ventricle were predictive of the success of the resuscitation. Progressive decreases in left pliance were associated with decreases in left ventricular diastolic and stroke volumes and progressed to a stone heart. |
11098957 | Prospective evaluation of short-term, high-volume isovolemic hemofiltration on the hemodynamic course and outcome in patients with intractable circulatory failure resulting from septic shock. | To evaluate the effects of short-term, high-volume hemofiltration (STHVH) on hemodynamic and metabolic status and 28-day survival in patients with refractory septic shock. |
11098958 | Effectiveness of end-tidal carbon dioxide tension for monitoring thrombolytic therapy in acute pulmonary embolism. | In acute massive pulmonary embolism with hemodynamic instability, monitoring of pulmonary artery pressure can be used to assess the efficacy of thrombolytic therapy. As a noninvasive alternative to pulmonary artery catheterization, we investigated the efficacy of continuous monitoring of end-tidal CO2 tension. |
11098959 | Stimulation of beta-adrenergic receptors inhibits the release of tumor necrosis factor-alpha from the isolated rat heart. | Beta-adrenergic receptor agonists such as isoproterenol inhibit production of tumor necrosis factor (TNF)-alpha in a number of cell types. Because the heart is a source of TNF-alpha, we hypothesized that isoproterenol would inhibit cardiac production of the cytokine. |
11098960 | Long-term health-related quality of life in survivors of sepsis. Short Form 36: a valid and reliable measure of health-related quality of life. | To describe the long-term health-related quality of life (HRQL) of survivors of sepsis and to evaluate the reliability and validity of the medical es study Short Form-36 (SF-36) in this population. |
11098961 | Hypocaloric total parenteral nutrition: effectiveness in prevention of hyperglycemia and infectious complications--a randomized clinical trial. | To determine whether the frequency rate of hyperglycemia and plications can be reduced by an underfeeding strategy in patients requiring total parenteral nutrition (TPN), without deleterious effects on nitrogen balance. |
11098962 | Midazolam and 2% propofol in long-term sedation of traumatized critically ill patients: efficacy and safety comparison. | We proposed pare the efficacy and safety of midazolam and propofol in its new preparation (2% propofol) when used for prolonged, deep sedation in traumatized, critically ill patients. We also pared 2% propofol with its original preparation, 1% propofol, used in a previous study in a similar and contemporary set of patients. |
11098963 | Safety of granulocyte colony-stimulating factor (filgrastim) in intubated patients in the intensive care unit: interim analysis of a prospective, placebo-controlled, double-blind study. | To investigate the safety of the granulocyte colony-stimulating factor filgrastim in the prevention of ial infections in intubated patients in the intensive care unit (ICU), with special emphasis on the possible deleterious effect on acute respiratory distress syndrome (ARDS) and the development of multiple organ dysfunction (MOD). |
11098964 | Intensive care unit drug use and subsequent quality of life in acute lung injury patients. | To examine the relationship between the use of sedative and neuromuscular blocking agents during a patient's intensive care unit (ICU) stay and subsequent measures of health-related quality of life. |
11098965 | Estimating cardiac filling pressure in mechanically ventilated patients with hyperinflation. | When positive end-expiratory pressure (PEEP) is applied, the intracavitary left ventricular end-diastolic pressure (LVEDP) exceeds the LV filling pressure because pericardial pressure exceeds 0 at end-expiration. Under those conditions, the LV filling pressure is itself better reflected by the transmural LVEDP (tLVEDP) (LVEDP minus pericardial pressure). By extension, end-expiratory pulmonary artery occlusion pressure (eePAOP), as an estimate of end-expiratory LVEDP, overestimates LV filling pressure when pericardial pressure is >0, because it occurs when PEEP is present. We hypothesized that LV filling pressure could be measured from eePAOP by also knowing the proportional transmission of alveolar pressure to pulmonary vessels calculated as index of transmission = (end-inspiratory PAOP--eePAOP)/(plateau pressure--total PEEP). We calculated transmural pulmonary artery occlusion pressure (tPAOP) with this equation: tPAOP = eePAOP--(index of transmission x total PEEP). pared tPAOP with airway disconnection nadir PAOP measured during rapid airway disconnection in subjects undergoing PEEP with and without evidence of dynamic pulmonary hyperinflation. |
11098966 | Total parenteral nutrition enriched with arginine and glutamate generates glutamine and limits protein catabolism in surgical patients hospitalized in intensive care units. | To study the effect of a parenteral nutrition solution enriched with potential precursors of glutamine, i.e., arginine and glutamate, on plasma glutamine concentrations and protein metabolism. |
11098967 | The comfort of breathing: a study with volunteers assessing the influence of various modes of assisted ventilation. | To assess the subjective feeling fort of healthy volunteers breathing on various modes of ventilation used in intensive care. |
11098968 | Jejunal and gastric mucosal perfusion versus splanchnic blood flow and metabolism: an observational study on postcardiac surgical patients. | To evaluate the association between changes in total splanchnic and mucosal perfusion, assessed either by gastric tonometry or jejunal laser Doppler flowmetry in postcardiac surgical patients. |
11098969 | Cysteinyl-leukotriene generation as a biomarker for survival in the critically ill. | To evaluate the capacity of cysteinyl-leukotriene generation in the progression of critical pared with that in healthy volunteers and to clarify interrelationships between the rate of leukotriene generation, severity of the disease, and clinical e. |
11098970 | Procalcitonin release patterns in a baboon model of trauma and sepsis: relationship to cytokines and neopterin. | Procalcitonin (PCT) has been described as an early, discriminating marker of bacteria-associated sepsis in patients. However, little is known of its source and actions, in part because no appropriate animal models have been available. We tested the hypothesis that plasma PCT increases during various pathophysiological conditions, such as hemorrhagic shock and sepsis, which differ with regard to the degree of associated endotoxemia. We further hypothesized that in sepsis, PCT would be significantly different in survivors vs. nonsurvivors. |
11098971 | Pediatric cardiac output measurement using surface integration of velocity vectors: an in vivo validation study. | To test the accuracy and reproducibility of systemic cardiac output (CO) measurements using surface integration of velocity vectors (SIVV) in a pediatric animal model with hemodynamic instability and pare SIVV with traditional pulsed-wave Doppler measurements. |
11098972 | A single endotoxin injection in the rabbit causes prolonged blood vessel dysfunction and a procoagulant state. | To determine the duration of vascular blood vessel dysfunction and coagulation abnormalities after administration of endotoxin in a nonlethal septic rabbit model. |
11098973 | Inhibition of nitric oxide synthase enhances the myocardial toxicity of phenylpropanolamine. | To investigate the direct and indirect effects of the anorexic agent phenylpropanolamine (PPA) on the heart and to determine whether nitric oxide deficiency exacerbates the myocardial toxicity of PPA. |
11098975 | Inducible nitric oxide synthase gene knockout mice have increased resistance to gut injury and bacterial translocation after an intestinal ischemia-reperfusion injury. | Intestinal ischemia-reperfusion after severe shock states is often associated with bacterial translocation and intestinal barrier dysfunction. Our previous studies showed that inducible nitric oxide synthase (iNOS) gene knockout mice were resistant to endotoxin-induced bacterial translocation and ileal mucosal damage. The goal of this study was to test whether iNOS mediates bacterial translocation after intestinal ischemia-reperfusion, using iNOS knockout mice (iNOS-/-) and their wild-type littermates (iNOS+/+). |
11098974 | Contact activation in shock caused by invasive group A Streptococcus pyogenes. | The aim of this study was to characterize abnormalities of coagulation in mice with experimental, invasive group A, streptococcal shock, in an attempt to explain the prolongation of the activated partial thromboplastin time identified in patients with streptococcal toxic shock syndrome. |
11098976 | An improved in vivo rat model for the study of mechanical ventilatory support effects on organs distal to the lung. | To study the influence of different mechanical ventilatory support strategies on organs distal to the lung, we developed an in vivo rat model, in which the effects of different tidal volume values can be studied while maintaining other indexes. |
11098977 | Bacterial translocation and tumor necrosis factor-alpha gene expression in experimental hemorrhagic shock. | To investigate whether bacterial translocation is the causative mechanism underlying cytokine production during hemorrhagic shock. |
11098978 | Effect of neutropenia and granulocyte colony stimulating factor-induced neutrophilia on blood-brain barrier permeability and brain edema after traumatic brain injury in rats. | Granulocyte colony stimulating factor (GCSF) has been used to increase systemic absolute neutrophil count (ANC) in patients with severe traumatic brain injury to reduce ial infection risk. However, the effect of increasing systemic ANC on the pathogenesis of experimental traumatic brain injury has not been studied. Thus, we evaluated the effect of systemic ANC on blood-brain barrier (BBB) damage and brain edema after traumatic brain injury in rats. |
11098979 | Improved outcomes of children with malignancy admitted to a pediatric intensive care unit. | To assess the acute and long-term es of children admitted to the intensive care unit with cancer plications after bone marrow transplantation. |
11098980 | Inhaled nitric oxide reduces the need for extracorporeal membrane oxygenation in infants with persistent pulmonary hypertension of the newborn. | We previously reported improved oxygenation, but no change, in rates of extracorporeal membrane oxygenation (ECMO) use or death among infants with persistent pulmonary hypertension of the newborn who received inhaled nitric oxide (NO) with conventional ventilation, irrespective of lung disease. The goal of our study was to determine whether treatment with inhaled NO improves oxygenation and clinical es in infants with persistent pulmonary hypertension of the newborn and associated lung disease who are ventilated with high-frequency oscillatory ventilation (HFOV). |
11098981 | Comparison of the response of saline tonometry and an automated gas tonometry device to a change in CO2. | To examine the speed of response of saline tonometry and an automated gas tonometry system by using standard tonometry catheters. |
11098982 | Percutaneous tracheostomy in critically ill patients: a prospective, randomized comparison of two techniques. | To pare monly used methods for percutaneous dilational tracheostomy (PDT) in critically ill patients. |
11098983 | Longitudinal study of pediatric house officers' attitudes toward death and dying. | To investigate pediatric residents' attitudes toward end-of-life issues and their education in dealing with these issues. |
11098984 | Position paper on critical care pharmacy services. Society of Critical Care Medicine and American College of Clinical Pharmacy Task Force on Critical Care Pharmacy Services. | The goal of the Task Force on Critical Care Pharmacy Services was to identify and describe the scope of practice that characterizes the critical care pharmacist and critical care pharmacy services. Specifically, the aims were to define the level of clinical practice and specialized skills characterizing the critical care pharmacist as clinician, educator, researcher, and manager; and to mend fundamental, desirable, and optimal pharmacy services and personnel requirements for the provision of pharmaceutical care to critically ill patients. Hospitals prehensive resources as well as those with more limited resources were considered. |
11099031 | Feedback control of intercellular signalling in development. | The munication that regulates cell fate during animal development must be precisely controlled to avoid dangerous errors. How is this achieved? Recent work has highlighted the importance of positive and negative feedback loops in the dynamic regulation of developmental signalling. These feedback interactions can impart precision, robustness and versatility to intercellular signals. Feedback failure can cause disease. |
11099032 | Ancient Egyptian chronology and the astronomical orientation of pyramids. | The ancient Egyptian pyramids at Giza have never been accurately dated, although we know that they were built approximately around the middle of the third millennium BC. The chronologies of this period have been reconstructed from surviving lists of kings and the lengths of their reigns, but the lists are rare, plete and contain known inconsistencies and errors. As a result, the existing chronologies for that period (the Old Kingdom) can be considered accurate only to about +/-100 years, a figure that radiocarbon dating cannot at present improve. Here I use trends in the orientation of Old Kingdom pyramids to demonstrate that the Egyptians aligned them to north by using the simultaneous transit of two circumpolar stars. Modelling the precession of these stars yields a date for the start of construction of the Great Pyramid that is accurate to +/-5 yr, thereby providing an anchor for the Old Kingdom chronologies. |
11099033 | Functional genomic analysis of C. elegans chromosome I by systematic RNA interference. | Complete genomic sequence is known for two multicellular eukaryotes, the nematode Caenorhabditis elegans and the fruit fly Drosophila melanogaster, and it will soon be known for humans. However, biological function has been assigned to only a small proportion of the predicted genes in any animal. Here we have used RNA-mediated interference (RNAi) to target nearly 90% of predicted genes on C. elegans chromosome I by feeding worms with bacteria that express double-stranded RNA. We have assigned function to 13.9% of the genes analysed, increasing the number of sequenced genes with known phenotypes on chromosome I from 70 to 378. Although most genes with sterile or embryonic lethal RNAi phenotypes are involved in basal cell metabolism, many genes giving post-embryonic phenotypes have conserved sequences but unknown function. In addition, conserved genes are significantly more likely to have an RNAi phenotype than are genes with no conservation. We have constructed a reusable library of bacterial clones that will permit unlimited RNAi screens in the future; this should help develop a plete view of the relationships between the genome, gene function and the environment. |
11099035 | Mean-field cluster model for the critical behaviour of ferromagnets. | Two separate theories are often used to characterize the paramagnetic properties of ferromagnetic materials. At temperatures T well above the Curie temperature, Tc (where the transition from paramagnetic to ferromagnetic behaviour occurs), classical mean-field theory yields the Curie-Weiss law for the magnetic susceptibility: X(T) infinity 1/(T - Weiss constant), where Weiss constant is the Weiss constant. Close to Tc, however, the standard mean-field approach breaks down so that better agreement with experimental data is provided by critical scaling theory: X(T) infinity 1/(T - Tc)gamma, where gamma is a scaling exponent. But there is no known model capable of predicting the measured values of gamma nor its variation among different substances. Here I use a mean-field cluster model based on finite-size thermostatistics to extend the range of mean-field theory, thereby eliminating the need for a separate scaling regime. The mean-field approximation is justified by using a kinetic-energy term to maintain the microcanonical ensembles. The model reproduces the Curie-Weiss law at high temperatures, but the classical Weiss transition at Tc = Weiss constant is suppressed by finite-size effects. Instead, the fraction of clusters with a specific amount of order diverges at Tc, yielding a transition that is mathematically similar to Bose-Einstein condensation. At all temperatures above Tc, the model matches the measured magnetic susceptibilities of crystalline EuO, Gd, Co and Ni, thus providing a unified picture for both the critical-scaling and Curie-Weiss regimes. |
11099034 | Functional genomic analysis of cell division in C. elegans using RNAi of genes on chromosome III. | Genome sequencing projects generate a wealth of information; however, the ultimate goal of such projects is to accelerate the identification of the biological function of genes. This creates a need prehensive studies to fill the gap between sequence and function. Here we report the results of a functional genomic screen to identify genes required for cell division in Caenorhabditis elegans. We inhibited the expression of approximately 96% of the approximately 2,300 predicted open reading frames on chromosome III using RNA-mediated interference (RNAi). By using an in vivo time-lapse differential interference contrast microscopy assay, we identified 133 genes (approximately 6%) necessary for distinct cellular processes in early embryos. Our results indicate that these genes represent most of the genes on chromosome III that are required for proper cell division in C. elegans embryos. plete data set, including sample time-lapse recordings, has been deposited in an open access database. We found that approximately 47% of the genes associated with a differential interference contrast phenotype have clear orthologues in other eukaryotes, indicating that this screen provides putative gene functions for other species as well. |
11099036 | Universal quantum computation with the exchange interaction. | Various physical implementations of puters are being investigated, although the requirements that must be met to make such devices a reality in the laboratory at present involve capabilities well beyond the state of the art. Recent solid-state approaches have used quantum dots, donor-atom nuclear spins or electron spins; in these architectures, the basic two-qubit quantum gate is generated by a tunable exchange interaction between spins (a Heisenberg interaction), whereas the one-qubit gates require control over a local magnetic field. Compared to the Heisenberg operation, the one-qubit operations are significantly slower, requiring substantially greater materials and plexity--potentially contributing to a detrimental increase in the decoherence rate. Here we introduced an explicit scheme in which the Heisenberg interaction alone suffices to implement exactly any puter circuit. This es at a price of a factor of three in additional qubits, and about a factor of ten in additional two-qubit operations. Even at this cost, the ability to eliminate plexity of one-qubit operations should accelerate progress towards solid-state implementations of putation. |
11099037 | Kondo physics in carbon nanotubes. | The connection of electrical leads to wire-like molecules is a logical step in the development of molecular electronics, but also allows studies of fundamental physics. For example, metallic carbon nanotubes are quantum wires that have been found to act as one-dimensional quantum dots, Luttinger liquids, proximity-induced superconductors and ballistic and diffusive one-dimensional metals. Here we report that electrically contacted single-walled carbon nanotubes can serve as powerful probes of Kondo physics, demonstrating the universality of the Kondo effect. Arising in the prototypical case from the interaction between a localized impurity magnetic moment and delocalized electrons in a metallic host, the Kondo effect has been used to explain enhanced low-temperature scattering from magnetic impurities in metals, and also occurs in transport through semiconductor quantum dots. The far greater tunability of dots (in our case, pared with atomic impurities renders new classes of Kondo-like effects accessible. Our nanotube devices differ from previous systems in which Kondo effects have been observed, in that they are one-dimensional quantum dots with three-dimensional metal (gold) reservoirs. This allows us to observe Kondo resonances for very large electron numbers (N) in the dot, and approaching the unitary limit (where the transmission reaches its maximum possible value). Moreover, we detect a previously unobserved Kondo effect, occurring for even values of N in a magnetic field. |
11099039 | Microseismological evidence for a changing wave climate in the northeast Atlantic Ocean. | One possible consequence of a change in climate over the past several decades is an increase in wave heights, potentially threatening coastal areas as well as the marine industry. But the difficulties in observing wave heights exacerbates a general problem of climate-change detection: inhomogeneities in long-term observational records owing to changes in the instruments or techniques used, which may cause artificial trends. Ground movements with periods of 4-16 seconds, known as microseisms, are associated with ocean waves and coastal surf, and have been recorded continuously since the early days of seismology. Here we use such a 40-year record of wintertime microseisms from Hamburg, Germany, to reconstruct the wave climate in the northeast Atlantic Ocean. For the period 1954-77, we detect an average of seven days per month with strong microseismic activity, without a significant trend. This number increases significantly in the second half of the record, reaching approximately 14 days of strong microseisms per month. The implied increase in northeast Atlantic wave height over the past 20 years parallels increased surface air temperatures and storminess in this region, suggesting mon forcing. |
11099038 | Increased marine production of N2O due to intensifying anoxia on the Indian continental shelf. | Eutrophication of surface waters and hypoxia in bottom waters has been increasing in many coastal areas, leading to very large depletions of marine life in the affected regions. These areas of high surface productivity and low bottom-water oxygen concentration are caused by increasing runoff of nutrients from land. Although the local ecological and socio-economic effects have received much attention, the potential contribution of increasing hypoxia to global-change phenomena is unknown. Here we report the intensification of one of the largest low-oxygen zones in the ocean, which develops naturally over the western Indian continental shelf during late summer and autumn. We also report the highest accumulations yet observed of hydrogen sulphide (H2S) and nitrous oxide (N2O) in open coastal waters. Increased N2O production is probably caused by the addition of anthropogenic nitrate and its subsequent denitrification, which is favoured by hypoxic conditions. We suggest that a global expansion of hypoxic zones may lead to an increase in marine production and emission of N2O, which, as a potent greenhouse gas, could contribute significantly to the accumulation of radiatively active trace gases in the atmosphere. |
11099040 | Fine-scale genetic structuring on Manacus manacus leks. | Leks have traditionally been considered as arenas where pete to attract females and secure matings. Thus, direct fitness benefits mediated petition between males to fertilize females have been considered to be the primary force driving the evolution of lekking behaviour. Inclusive fitness benefits mediated through kin selection may also be involved in lek formation and evolution, but to date this theory has been largely ignored. According to kin-selection theory, both reproducing and non-reproducing males may gain indirect inclusive fitness benefits. If females are attracted to larger leks, non-reproducing males add attractiveness to a lek, and therefore, in a genetically structured population, boost the reproductive success of kin. Theory predicts that the attractiveness of leks is plastic, and that males establish themselves on a lek in which the top male, in terms of reproductive success, is a close relative. Here we show that in white-bearded manakins (Manacus manacus), for which larger leks are more attractive to females and so secure the maximum number of matings, there is extraordinary fine-scale genetic structure, with leks posed of clusters of related kin. We propose that males establish themselves where they find relatives to such an extent that they form groups within leks, and that such behaviour is consistent with kin-selection theory to maximize reproductive success of the group. |
11099041 | Repeated, recent and diverse transfers of a mitochondrial gene to the nucleus in flowering plants. | A ponent of the endosymbiotic theory for the bacterial origin of the mitochondrion is that many of its genes were transferred to the nucleus. Most of this transfer occurred early in mitochondrial evolution; functional transfer of mitochondrial genes has ceased in animals. Although mitochondrial gene transfer continues to occur in plants, prehensive study of the frequency and timing of transfers during plant evolution has been conducted. Here we report frequent loss (26 times) and transfer to the nucleus of the mitochondrial gene rps10 among 277 diverse angiosperms. Characterization of nuclear rps10 genes from 16 out of 26 loss lineages implies that many independent, RNA-mediated rps10 transfers occurred during recent angiosperm evolution; each of the genes may represent a separate functional gene transfer. Thus, rps10 has been transferred to the nucleus at a surprisingly high rate during angiosperm evolution. The structures of several nuclear rps10 genes reveal diverse mechanisms by which transferred genes e activated, including parasitism of pre-existing nuclear genes for mitochondrial or cytoplasmic proteins, and activation without gain of a mitochondrial targeting sequence. |
11099042 | Imagery neurons in the human brain. | Vivid visual images can be voluntarily generated in our minds in the absence of simultaneous visual input. While trying to count the number of flowers in Van Gogh's Sunflowers, understanding a description or recalling a path, subjects report forming an image in their "mind's eye". Whether this process is plished by the same neuronal mechanisms as visual perception has long been a matter of debate. Evidence from functional imaging, psychophysics, neurological studies and monkey electrophysiology suggests mon process, yet there are patients with deficits in one but not the other. Here we directly investigated the neuronal substrates of visual recall by recording from single neurons in the human medial temporal lobe while the subjects were asked to imagine previously viewed images. We found single neurons in the hippocampus, amygdala, entorhinal cortex and parahippocampal gyrus that selectively altered their firing rates depending on the stimulus the subjects were imagining. Of the neurons that fired selectively during both vision and imagery, the majority (88%) had identical selectivity. Our study reveals single neuron correlates of volitional visual imagery in humans and suggests mon substrate for the processing of ing visual information and visual recall. |
11099043 | Real-time prediction of hand trajectory by ensembles of cortical neurons in primates. | Signals derived from the rat motor cortex can be used for controlling one-dimensional movements of a robot arm. It remains unknown, however, whether real-time processing of cortical signals can be employed to reproduce, in a robotic device, the kind plex arm movements used by primates to reach objects in space. Here we recorded the simultaneous activity of large populations of neurons, distributed in the premotor, primary motor and posterior parietal cortical areas, as non-human primates performed two distinct motor tasks. Accurate real-time predictions of one- and three-dimensional arm movement trajectories were obtained by applying both linear and nonlinear algorithms to cortical neuronal ensemble activity recorded from each animal. In addition, cortically derived signals were successfully used for real-time control of robotic devices, both locally and through the Internet. These results suggest that long-term control plex prosthetic robot arm movements can be achieved by simple real-time transformations of neuronal population signals derived from multiple cortical areas in primates. |
11099044 | A regulator of transcriptional elongation controls vertebrate neuronal development. | The development of distinct vertebrate neurons is defined by the unique profiles of genes that neurons express. It is accepted that neural genes are regulated at the point of transcription initiation, but the role of messenger RNA elongation in neural gene regulation has not been examined. Here we describe the mutant foggy, identified in a genetic screen for mutations that affect neuronal development in zebrafish, that displayed a reduction of dopamine-containing neurons and a corresponding surplus of serotonin-containing neurons in the hypothalamus. Positional cloning disclosed that Foggy is a brain-enriched nuclear protein that is structurally related to the transcription elongation factor Spt5 (refs 5-12). Foggy is not part of the basic transcription apparatus but a phosphorylation-dependent, dual regulator of transcription elongation. The mutation disrupts its repressive but not its stimulatory activity. Our results provide molecular, genetic and biochemical evidence that negative regulators of transcription elongation control key aspects of neuronal development. |
11099045 | ClC-5 Cl- -channel disruption impairs endocytosis in a mouse model for Dent's disease. | Dent's disease is an X-linked disorder associated with the urinary loss of low-molecular-weight proteins, phosphate and calcium, which often leads to kidney stones. It is caused by mutations in ClC-5, a renal chloride channel that is expressed in endosomes of the proximal tubule. Here we show that disruption of the mouse clcn5 gene causes proteinuria by strongly reducing apical proximal tubular endocytosis. Both receptor-mediated and fluid-phase endocytosis are affected, and the internalization of the apical transporters NaPi-2 and NHE3 is slowed. At steady state, however, both proteins are redistributed from the plasma membrane to intracellular vesicles. This may be caused by an increased stimulation of luminal parathyroid hormone (PTH) receptors owing to the observed decreased tubular endocytosis of PTH. The rise in luminal PTH concentration should also stimulate the hydroxylation of 25(OH) vitamin D3 to the active hormone. However, this is counteracted by a urinary loss of the precursor 25(OH) vitamin D3. The balance between these opposing effects, both of which are secondary to the defect in proximal tubular endocytosis, probably determines whether there will be hypercalciuria and kidney stones. |
11099046 | The Eps8 protein coordinates EGF receptor signalling through Rac and trafficking through Rab5. | How epidermal growth factor receptor (EGFR) signalling is linked to EGFR trafficking is largely unknown. Signalling and trafficking involve small GTPases of the Rho and Rab families, respectively. But it remains unknown whether the signalling relying on these two classes of GTPases is integrated, and, if it is, what molecular machinery is involved. Here we report that the protein Eps8 connects these signalling pathways. Eps8 is a substrate of the EGFR, which is held in plex with Sos1 by the adaptor protein E3bl (ref. 2), thereby mediating activation of Rac. Through its src homology-3 domain, Eps8 interacts with RN-tre. We show that RN-tre is a Rab5 GTPase-activating protein, whose activity is regulated by the EGFR. By entering in plex with Eps8, RN-tre acts on Rab5 and inhibits internalization of the EGFR. Furthermore, RN-tre diverts Eps8 from its Rac-activating function, resulting in the attenuation of Rac signalling. Thus, depending on its state of association with E3b1 or RN-tre, Eps8 participates in both EGFR signalling through Rac, and trafficking through Rab5. |
11099047 | Deacetylation of p53 modulates its effect on cell growth and apoptosis. | The p53 tumour suppressor is a transcriptional factor whose activity is modulated by protein stability and post-translational modifications including acetylation. The mechanism by which acetylated p53 is maintained in vivo remains unclear. Here we show that the deacetylation of p53 is mediated by an histone deacetylase-1 plex. We have also purified a p53 target protein in the plexes (designated PID; but identical to metastasis-associated protein 2 (MTA2)), which has been identified as ponent of the plex. PID specifically interacts with p53 both in vitro and in vivo, and its expression reduces significantly the steady-state levels of acetylated p53. PID expression strongly represses p53-dependent transcriptional activation, and, notably, it modulates p53-mediated cell growth arrest and apoptosis. These results show that deacetylation and functional interactions by the PID/MTA2-associated plex may represent an important pathway to regulate p53 function. |
11099048 | Insights into SCF ubiquitin ligases from the structure of the Skp1-Skp2 complex. | F-box proteins are members of a large family that regulates the cell cycle, the immune response, signalling cascades and developmental programmes by targeting proteins, such as cyclins, cyclin-dependent kinase inhibitors, IkappaBalpha and beta-catenin, for ubiquitination (reviewed in refs 1-3). F-box proteins are the ponents of SCF (Skp1-Cullin-F-box protein) ubiquitin-protein ligases. They bind the SCF constant catalytic core by means of the F-box motif interacting with Skp1, and they bind substrates through their variable protein-protein interaction domains. The large number of F-box proteins is thought to allow ubiquitination of numerous, diverse substrates. Most organisms have several Skp1 family members, but the function of these Skp1 homologues and the rules of recognition between different F-box and Skp1 proteins remain unknown. Here we describe the crystal structure of the human F-box protein Skp2 bound to Skp1. Skp1 recruits the F-box protein through a bipartite interface involving both the F-box and the substrate-recognition domain. The structure raises the possibility that different Skp1 family members evolved to function with different subsets of F-box proteins, and suggests that the F-box protein may not only recruit substrate, but may also position it optimally for the ubiquitination reaction. |
11099049 | The production of pyrethrins by plant cell and tissue cultures of Chrysanthemum cinerariaefolium and Tagetes species. | Pyrethrins, the most economically important natural prise a group of six closely related monoterpene esters. The industrial production is based on their extraction from Chrysanthemum cinerariaefolium (Pyrethrum) capitula. The world production of natural pyrethrins still falls short of global market demand stimulating the research in in vitro production as an alternative to conventional cultivation methods. The different biotechnological alternatives such as callus cultures, shoot and root cultures, plant cell suspension cultures, and bioconversion of precursors by means of enzymatic synthesis or genetically engineered microorganisms, as well as the progress achieved in methods for the identification and quantitation of pounds have been reviewed. Although technology for plant cell culture exists, industrial applications have, to date, been limited due to both the low economical viability and technological feasibility at large scale. Bioconversion of readily available precursors looks more attractive, but more research is needed before this technology is used for the industrial production of pyrethrins. |
11099053 | A multicenter, randomized, double-blind clinical trial examining the effect of oral human recombinant epidermal growth factor on the healing of duodenal ulcers. | Our aim was to study the efficacy of oral human binant epidermal growth factor (EGF) in the treatment of duodenal ulcers, on the basis of its repairing actions in the gastrointestinal tract. |
11099054 | Eradication of Helicobacter pylori compared with long-term acid suppression in duodenal ulcer disease. A randomized trial with 2-year follow-up. The Danish Ulcer Study Group. | Trials evaluating long-term management of duodenal ulcer disease have mainly been focused on recurrence of ulcers, disregarding effects on dyspeptic and reflux symptoms. Profound acid inhibition with a proton pump inhibitor is the gold standard therapy in acid-related diseases. We aimed pare the symptomatic effects of eradication therapy with those of long-term omeprazole treatment in a design with periods both with and without acid inhibition. |
11099055 | Different patterns of Helicobacter pylori adherence to gastric mucosa cells in children and adults. An ultrastructural study. | Infection with Helicobacter pylori in childhood may be the initiation of a lifelong coexistence between microorganisms and epithelial cells resulting in chronic inflammation. The adhesion pattern of H. pylori found in antral biopsies from a group of H. pylori-infected children with recurrent abdominal pain pared with a group of H. pylori-infected adults suffering from dyspepsia, in an attempt to reveal differences in the type of adhesion. |
11099056 | Effects of age on proximal gastric motor and sensory function. | Healthy aging is associated with a reduction in appetite and food intake, which may predispose to pathologic weight loss and malnutrition. Changes in intragastric mechanisms mediating satiation in the elderly have not been studied. The aim of this study was to evaluate the effects of aging on i) fasting pliance and the perception of gastric distension, and ii) food intake and gastric modation to a meal. |
11099057 | Fructose- and sorbitol-reduced diet improves mood and gastrointestinal disturbances in fructose malabsorbers. | Fructose malabsorption is characterized by the inability to absorb fructose efficiently. As a consequence fructose reaches the colon where it is broken down by bacteria to short fatty acids, CO2 and H2. Bloating, cramps, osmotic diarrhea and other symptoms of irritable bowel syndrome are the consequences and can be seen in about 50% of fructose malabsorbers. We have previously shown that fructose malabsorption is associated with early signs of mental depression and low serum tryptophan concentrations. It was therefore of interest whether a fructose-reduced diet could not only improve plaints but also depressive signs seen in fructose malabsorbers. |
11099058 | Increased permeability in dextran sulphate colitis in rats: time course of development and effect of butyrate. | Increased mucosal permeability is an important factor in the genesis of mucosal inflammation in inflammatory bowel disease. This study examined the time course of increased permeability and the effect of butyrate on permeability in experimental colitis in rats. |
11099059 | The dietary combination of germinated barley foodstuff plus Clostridium butyricum suppresses the dextran sulfate sodium-induced experimental colitis in rats. | Recent studies have suggested that dietary fiber exerts a therapeutic effect on IBD patients. The aim of this study was to evaluate the effects of a bination of germinated barley foodstuff (GBF), derived from the aleurone and scutellum fraction of germinated barley, plus Clostridium butyricum against dextran sulfate sodium (DSS)-induced experimental colitis in rats. |
11099060 | Quality of life study in a regional group of patients with Crohn disease. A structured interview study. | The course and prognosis of Crohn disease has previously been described in a regional group of patients in Copenhagen County. The aim of the present study was to reveal the quality of life. as judged by the patients, pared to age- and sex-matched healthy controls. |
11099061 | Concordance of inflammatory bowel disease among Danish twins. Results of a nationwide study. | Previous studies have shown an increased risk of inflammatory bowel disease (IBD) among relatives of patients with Crohn disease and ulcerative colitis. In the present study the probandwise concordance rates for ulcerative colitis and Crohn disease among mono- and dizygotic twins were estimated. Further we aimed to evaluate whether smoking habits might influence the concordance, and to look for clinical characteristics of concordant versus discordant twin pairs. |
11099062 | The epidemiology of oesophageal adenocarcinoma: has the cancer of gastric cardia an influence on the rising incidence of oesophageal adenocarcinoma? | Owing to overgrowth and definitional problems in classification, the cancer of gastric cardia may affect significantly the epidemiological analysis of oesophageal adenocarcinoma. The purpose of the present study was to evaluate the changes in the incidence of all the adenocarcinomas near the gastrooesophageal junction. |
11099063 | N-acetyltransferase 2 (NAT2) genotype and colorectal carcinoma: risk variability according to tumour site? | Dietary heterocyclic aromatic amines (HAAs) are members of a family of chemicals prise highly pounds related to colon cancer. The polymorphic N-acetyltransferase 2 enzyme (NAT2, E.C. 2.3.1.5) plays a key role in the transformation of HAAs to ultimate carcinogens. NAT2 enzyme activity is expressed in a genotype-dependent manner in colon epithelium. Therefore local activation of HAAs in colon, and hence increased risk to develop colon cancer, is likely to be related to high NAT2 enzyme activity. This study is aimed at analysing the association between genotypes leading to high NAT2 activity and colorectal cancer risk. |
11099064 | C5b-9 and interleukin-6 in chronic hepatitis C. Surrogate markers predicting short-term response to interferon alpha-2b. | Available data and our observations suggest that elevated levels of interleukin (IL)-6 and -10 and plement parameters may be associated with a poor response to IFN alpha. We evaluated how baseline levels of C5b-9, IL-6, and IL-10 influence the e of IFN alpha treatment. |
11099066 | Electrogenic ion transport in duodenum, an aid in cystic fibrosis diagnosis. | Abnormality in chloride transport across epithelial tissues is a basic defect in cystic fibrosis (CF). Our aim was pare the induced chloride secretion in duodenum in CF patients with different mutations. |
11099065 | Role of nitric oxide and endothelin-1 in a portal hypertensive rat model. | Portal hypertension is often panied by a hyperdynamic circulation state. Some reports have suggested that nitric oxide (NO) plays an important role in this hyperdynamic state. On the other hand, although endothelin (ET)-1, a powerful vasoconstrictor, was recently identified, little is known about its role in portal hypertension or about the interaction between NO and ET-1. The aim of this study was therefore to investigate whether or not the inhibitor of NO synthase (NOS) might improve portal hypertension, and also to clarify the relationship between NO and ET-1. |
11099067 | Incidence and mortality of acute pancreatitis between 1985 and 1995. | The incidence of acute pancreatitis seems to have increased in Western countries. It has been suggested that this increase can be explained by improved diagnostic procedures. We performed a nationwide study to assess the annual sex- and age-specific incidence and mortality rates of acute pancreatitis in the Netherlands between 1985 and 1995, a period in which diagnostic procedures did not change considerably. |
11099068 | Eradication of hepatitis C virus 1b by interferon in a health care worker with acute hepatitis following needlestick transmission from a patient with chronic hepatitis C unresponsive to interferon. | Hepatitis C virus (HCV) was successfully eradicated by a short course of interferon (IFN) therapy in a nurse with acute HCV infection from a needlestick accident. The source patient had chronic hepatitis C and was a nonresponder to IFN therapy. The HCV genotype was 1b in patients, and a single point mutation (H-->R in amino acid 2218) was observed in the IFN sensitivity-determining region of the nonstructural 5A gene, parison with sequences of HCV-J, in HCV RNA from both the source patient (before and after IFN therapy) and the recipient (before IFN therapy). Though the strain transmitted was believed to be IFN-resistant in the patient with chronic hepatitis, the patient with acute hepatitis had a sustained response. |
11099071 | Some methodological issues in the study of sexual networks: from model to data to model. | Mixing between sexual activity classes is an important determinant of sexually transmitted disease transmission. However, attempts to estimate sexual mixing patterns in the field remain limited partly because of practical and methodological difficulties. |
11099072 | Influence of mathematical modeling of HIV and AIDS on policies and programs in the developing world. | A number of simulation models have been developed to explore the dynamics of the AIDS epidemic. There seems to be minimal impact of these models on policies and programs. |
11099074 | Epidemiology and control and curable sexually transmitted diseases: opportunities and problems. | Despite the availability of safe and effective treatment, infection with bacterial sexually transmitted diseases persists at a high prevalence in many populations. |
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