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91.
A key claudin extracellular loop domain is critical for epithelial barrier integrity 总被引:2,自引:0,他引:2
Mrsny RJ Brown GT Gerner-Smidt K Buret AG Meddings JB Quan C Koval M Nusrat A 《The American journal of pathology》2008,172(4):905-915
Intercellular tight junctions (TJs) regulate epithelial barrier properties. Claudins are major structural constituents of TJs and belong to a large family of tetra-spanning membrane proteins that have two predicted extracellular loops (ELs). Given that claudin-1 is widely expressed in epithelia, we further defined the role of its EL domains in determining TJ function. The effects of several claudin-1 EL mimetic peptides on epithelial barrier structure and function were examined. Incubation of model human intestinal epithelial cells with a 27-amino acid peptide corresponding to a portion of the first EL domain (Cldn-1(53-80)) reversibly interfered with epithelial barrier function by inducing the rearrangement of key TJ proteins: occludin, claudin-1, junctional adhesion molecule-A, and zonula occludens-1. Cldn-1(53-80) associated with both claudin-1 and occludin, suggesting both the direct interference with the ability of these proteins to assemble into functional TJs and their close interaction under physiological conditions. These effects were specific for Cldn-1(53-80), because peptides corresponding to other claudin-1 EL domains failed to influence TJ function. Furthermore, the oral administration of Cldn-1(53-80) to rats increased paracellular gastric permeability. Thus, the identification of a critical claudin-1 EL motif, Cldn-1(53-80), capable of regulating TJ structure and function, offers a useful adjunct to treatments that require drug delivery across an epithelial barrier. 相似文献
92.
Papanikolaou EG D'haeseleer E Verheyen G Van de Velde H Camus M Van Steirteghem A Devroey P Tournaye H 《Human reproduction (Oxford, England)》2005,20(11):3198-3203
INTRODUCTION: In a randomized controlled trial, we assessed whether pregnancy outcome would be improved by extending embryo culture to day 5 and transferring a blastocyst in patients with at least four good-quality embryos on day 3. METHODS: Multifollicular ovarian stimulation was performed with a GnRH agonist in 44% of patients and with a GnRH antagonist in 56%. Overall, 164 patients younger than 37 years fulfilled embryo quality criteria (at least four having at least six cells on the morning of day 3, maximum 20% anucleate fragments) on the third day of culture and were randomized to the day 3 (n = 84) or day 5 (n = 80) groups. Equal numbers of embryos (n = 2) were transferred in each group. RESULTS: Demographics, stimulation parameters and embryological data were comparable in the two groups. Blastocyst-stage transfer resulted in a significantly higher ongoing pregnancy rate [51.3 versus 27.4%; odds ratio (OR) 2.78, 95% confidence interval (CI) 1.45-5.34] and live birth rate (47.5 versus 27.4%; OR 2.40, 95% CI 1.25-4.59) compared with day-3 embryo transfer. A high twin birth rate was observed in both groups (36.8 versus 30.4%; P > 0.05). CONCLUSIONS: A threshold of four good embryos on the third day of embryo culture appears to indicate that the patient will benefit from embryo transfer at the blastocyst stage and have a better chance of achieving a live delivery than with cleavage-stage embryo transfer. 相似文献
93.
Jillella AP Ustun C Robach E Sertkaya D DiPiro C Kallab AM Brick WG Dainer PM Kutlar A Townsend AR Burgess RE 《Journal of hematotherapy & stem cell research》2003,12(2):155-160
The purpose of this retrospective study was to evaluate infectious complications in patients receiving mobilization chemotherapy for stem cell collection prior to autologous peripheral blood stem cell transplantation. An additional goal was to evaluate risk factors associated with the development of infectious complications. At the Medical College of Georgia BMT center, 54 patients were administered mobilization chemotherapy for the purpose of collecting stem cells between June, 1997, and May, 2002. All patients received Filgrastim in addition to chemotherapy, and 50 of 54 patients received prophylactic acyclovir, fluconazole, and ciprofloxacin until neutrophil recovery. The median duration to neutrophil recovery was 11 days. Fourteen of 54 (26%) patients developed fever/infections during the mobilization phase. One patient developed both a catheter-related infection and Clostridium difficile colitis, increasing the total number of infectious episodes to 15. Twelve patients had a documented site of infection whereas 2 patients had neutropenic fever with no identifiable source. Eight of the 15 (55%) infections were Gram-positive catheter infections. All the patients were treated successfully with antibiotics. No systemic fungal infections were identified and none of the patients died from complications related to mobilization chemotherapy. Logistic regression was applied for univariate and multivariate analysis and showed that age, sex, diagnosis, neutrophil recovery, disease status, use of salvage chemotherapy, and mobilization regimen used did not affect the infection rate. In our series of 54 patients, 14 patients developed fever/infections during mobilization. Although there is a substantial risk of infectious complications among patients who receive mobilization chemotherapy, it is not clear that prophylactic antibiotics decrease infectious complications. Because the vast majority of infections are Gram-positive catheter infections, it appears reasonable to employ Gram-positive prophylaxis. Controlled studies should be conducted to define the optimum mobilization regimens as well as the optimum combination of prophylactic antibiotics. 相似文献
94.
Improved disease-free-survival after transplantation of peripheral blood stem cells as compared with bone marrow from HLA-identical unrelated donors in patients with first chronic phase chronic myeloid leukemia 总被引:8,自引:3,他引:8 下载免费PDF全文
Elmaagacli AH Basoglu S Peceny R Trenschel R Ottinger H Lollert A Runde V Grosse-Wilde H Beelen DW Schaefer UW 《Blood》2002,99(4):1130-1135
Outcomes after peripheral blood stem cell transplantation (PBSCT) for chronic phase chronic myeloid leukemia (n = 37) were compared with outcomes after bone marrow transplantation (BMT) (n = 54) in the HLA-compatible unrelated donor setting. Median follow-up was 17 months after PBSCT and 29 months after BMT. Both neutrophil and platelet recovery were faster after PBSCT (P <.05). PBSCT was associated with improved immune reconstitution, with higher peripheral blood naive (CD4(+)CD45RA(+)) and memory (CD4(+) CD45RO(+)) helper T cells at 3 months and 12 months after transplantation (P <.03). The cumulative incidence of acute (grades II-IV) and chronic graft-versus-host disease (GVHD) were similar, but BMT was associated with a higher cumulative incidence of severe, acute (grade III-IV) GVHD at 24% as compared with 8% with PBSCT (P <.05). Molecular relapse, defined by 2 consecutive positive polymerase chain reaction assays for bcr-abl within a 4-week interval, occurred in 12 of 45 evaluable patients (27%) after BMT and in 4 of 37 (11%) after PBSCT (not significant). Cytogenetic relapse occurred in 5 of 54 patients after BMT (9%) and in 1 of the 37 (3%) patients after PBSCT (not significant). Seventeen of the 54 patients died after BMT (31%), as compared with 2 of 37 patients after PBSCT (5%). Deaths in the BMT group were associated mainly with infections and severe, acute GVHD. The estimated probability of transplant-related mortality (TRM) and disease-free survival at 1000 days after receiving the transplant were 30% and 64% in the BMT group and 5% and 91% in the PBSCT group (P <.03). Overall survival 1000 days after receiving the transplant was 66% after BMT and 94% after PBSCT (P <.02). In the multivariate analysis, only acute GVHD significantly influenced TRM (P <.01). 相似文献
95.
Assessment of appropriate laboratory measurements to supplement the Crohn's disease activity index. 总被引:7,自引:0,他引:7 下载免费PDF全文
The ability of 11 laboratory parameters to reflect the degree of activity of Crohn's disease, using a clinical index as reference point was compared by means of multiple stepwise regression analysis. Activity was best defined in decreasing order by orosomucoid, sedimentation rate, C reactive protein, alpha-1-antitrypsin, albumin, haematocrit, IgM, circulating immune complexes, serum iron, IgG, and IgA. The haematocrit, the only laboratory measurement in the Crohn's disease activity index developed by the National Cooperative Study Group in the USA, is less discriminant than acute phase reactants. Only three parameters-namely, orosomucoid, sedimentation rate, and C reactive protein-have a significant weight and should be complementary to a simple clinical index. 相似文献
96.
97.
98.
José Gon?alves Pereira Bravo Edson Ide Andre Kondo Diogo Turiani Hourneaux de Moura Eduardo Turiani Hourneaux de Moura Paulo Sakai Wanderley Marques Bernardo Eduardo Guimar?es Hourneaux de Moura 《Clinics (S?o Paulo, Brazil)》2016,71(3):169-178
To compare the complications and mortality related to gastrostomy procedures performed using surgical and percutaneous endoscopic gastrostomy techniques, this review covered seven studies. Five of these were retrospective and two were randomized prospective studies. In total, 406 patients were involved, 232 of whom had undergone percutaneous endoscopic gastrostomy and 174 of whom had undergone surgical gastrostomy. The analysis was performed using Review Manager. Risk differences were computed using a fixed-effects model and forest and funnel plots. Data on risk differences and 95% confidence intervals were obtained using the Mantel-Haenszel test. There was no difference in major complications in retrospective (95% CI (-0.11 to 0.10)) or randomized (95% CI (-0.07 to 0.05)) studies. Regarding minor complications, no difference was found in retrospective studies (95% CI (-00.17 to 0.09)), whereas a difference was observed in randomized studies (95% CI (-0.25 to -0.02)). Separate analyses of retrospective and randomized studies revealed no differences between the methods in relation to mortality and major complications. Moreover, low levels of minor complications were observed among endoscopic procedures in randomized studies, with no difference observed compared with retrospective studies. 相似文献
99.
Arrell DK Niederländer NJ Faustino RS Behfar A Terzic A 《Stem cells (Dayton, Ohio)》2008,26(2):387-400
In the developing embryo, instructive guidance from the ventral endoderm secures cardiac program induction within the anterolateral mesoderm. Endoderm-guided cardiogenesis, however, has yet to be resolved at the proteome level. Here, through cardiopoietic priming of the endoderm with the reprogramming cytokine tumor necrosis factor alpha (TNFalpha), candidate effectors of embryonic stem cell cardiac differentiation were delineated by comparative proteomics. Differential two-dimensional gel electrophoretic mapping revealed that more than 75% of protein species increased >1.5-fold in the TNFalpha-primed versus unprimed endodermal secretome. Protein spot identification by linear ion trap quadrupole (LTQ) tandem mass spectrometry (MS/MS) and validation by shotgun LTQ-Fourier transform MS/MS following multidimensional chromatography mapped 99 unique proteins from 153 spot assignments. A definitive set of 48 secretome proteins was deduced by iterative bioinformatic screening using algorithms for detection of canonical and noncanonical indices of secretion. Protein-protein interaction analysis, in conjunction with respective expression level changes, revealed a nonstochastic TNFalpha-centric secretome network with a scale-free hierarchical architecture. Cardiovascular development was the primary developmental function of the resolved TNFalpha-anchored network. Functional cooperativity of the derived cardioinductive network was validated through direct application of the TNFalpha-primed secretome on embryonic stem cells, potentiating cardiac commitment and sarcomerogenesis. Conversely, inhibition of primary network hubs negated the procardiogenic effects of TNFalpha priming. Thus, proteomic cartography establishes a systems biology framework for the endodermal secretome network guiding stem cell cardiopoiesis. 相似文献
100.
A haplotype block downstream of plasminogen is associated with chronic and aggressive periodontitis 下载免费PDF全文
Yvonne Jockel‐Schneider Knut Adam Per Hoffman Klaus Berger Thomas Kocher Jörg Meyle Peter Eickholz Christof Doerfer Matthias Laudes André Uitterlinden Wolfgang Lieb Andre Franke Stefan Schreiber Steven Offenbacher Kimon Divaris Corinna Bruckmann Bruno G. Loos Søeren Jepsen Henrik Dommisch Arne S. Schäefer 《Journal of clinical periodontology》2017,44(10):962-970