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排序方式: 共有200条查询结果,搜索用时 335 毫秒
81.
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83.
Effects of resuscitation fluids on nonadaptive immune responses 总被引:7,自引:0,他引:7
BACKGROUND: Colloidal plasma-expander fluids are commonly used as an alternative to blood components in the resuscitation of patients suffering from hemorrhagic shock and trauma. Of these, hydroxyethyl starch is also used as a cryopreservative, and these dual properties have been utilized in the development of a blood storage system that allows the direct transfusion of red cells. The prolonged intravascular persistence of hydroxyethyl starch suggests that phagocytic clearance may be impaired and that the presence of hydroxyethyl starch could exacerbate transfusion-induced immunomodulation. STUDY DESIGN AND METHODS: The effects of colloidal resuscitation fluids on the activation response and phagocytic function of polymorphonuclear cells (PMNs) and monocytes in normal peripheral blood were examined. To mimic the hemolysis associated with cryopreservation, the effects of 1- and 5- percent red cell lysate were studied. Flow cytometric assays were used in all cases. RESULTS: The percentage of phagocytic monocytes and PMNs was not altered; nor were the rates of phagocytosis impaired after incubation with resuscitation fluids. Upregulation of cell surface integrin during activation was similarly unmodified by the fluids. CONCLUSION: Hydroxyethyl starch and other resuscitation fluids do not affect some important antimicrobial functions of the nonadaptive arm of the immune response. This suggests that posttrauma or transfusion- induced immunomodulation is not exacerbated by inhibition at this level. 相似文献
84.
Parathyroid hormone‐related protein (PTHrP) is an integral mediator of physiologic and pathologic processes and has demonstrated actions in the periodontium. PTHrP functions via AP‐1, and specifically through JunB. This study identified JunB‐dependent downstream mediators of PTHrP using OCCM cementoblastic transfectants with JunB over‐ or reduced expression. Over‐expressing cells showed an increase in proliferation, while the opposite was seen in siRNA transfected cells. Microarray analysis of over‐expressing cells revealed more than 1000 regulated genes. Three genes were investigated in more detail. The PTH/PTHrP receptor (PTHR1) and ephrin B1 (EfnB1) were down‐regulated, and vascular cell adhesion molecule‐1 (VCAM‐1) was up‐regulated with JunB over‐expression. JunB siRNA transfectants had increased PTHR1, but reduced ephrin B1 and unaltered VCAM‐1 in vitro. To validate these targets, parental OCCM cells and primary osteoblasts were treated with PTHrP, resulting in reduced PTHR1 and ephrin B1, and increased VCAM‐1. Cell transfectants were implanted subcutaneously in vivo, and microarray analysis and RT‐PCR performed. Over‐expression of JunB down‐regulated PTHR1 and ephrin B1, and increased VCAM‐1. JunB siRNA transfectant implants had increased PTHR1 and ephrin B1, but no altered VCAM‐1. These data highlight new gene targets for PTHrP and indicate JunB is a critical mediator of PTHrP actions. 相似文献
85.
86.
IgG and IgM anti-A and/or -B agglutinin titers were determined on 17 serum samples (5 group 0, 7 group A, 5 group B) to range from 8 to 1024. The presence of hemolysins was also evaluated. Single adsorptions with solid-state synthetic A and B substances greatly reduced or eliminated anti-A and -B titers but did not adsorb known platelet antibodies. Unadsorbed and adsorbed serum samples were crossmatched with ABO-compatible and -incompatible platelets by a radioimmunoassay employing 125I-labeled monoclonal antibodies specific for human gamma, mu, and C3d antigens. IgG and IgM crossmatch incompatibility was directly related to ABO alloantibody titers greater than or equal to 64. The use of adsorbed serum in the crossmatch eliminated or greatly reduced incompatible results that were due to ABO alloagglutinins alone, thus allowing the reliable detection of platelet and/or HLA antibodies. 相似文献
87.
Grace?TY?Chung Rossa?WK?Chiu Jo?LK?Cheung Yongjie?Jin Stephen?SC?Chim Paul?KS?Chan YM?Dennis?LoEmail author 《BMC infectious diseases》2005,5(1):87
Background
The Severe Acute Respiratory Syndrome (SARS) was a newly emerged infectious disease which caused a global epidemic in 2002–2003. Sequence analysis of SARS-coronavirus isolates revealed that specific genotypes predominated at different periods of the epidemic. This information can be used as a footprint for tracing the epidemiology of infections and monitor viral evolution. However, direct sequencing analysis of a large number of clinical samples is cumbersome and time consuming. We present here a simple and rapid assay for the screening of SARS-coronavirus genotypes based on the use of fluorogenic oligonucleotide probes for allelic discrimination. 相似文献88.
Koyasu S; Clayton LK; Lerner A; Heiken H; Parkes A; Reinherz EL 《International immunology》1997,9(10):1475-1480
89.
Vascular endothelial growth factor production by human luteinized granulosa cells in vitro 总被引:10,自引:2,他引:10
Lee A; Christenson LK; Patton PE; Burry KA; Stouffer RL 《Human reproduction (Oxford, England)》1997,12(12):2756-2761
Vascular endothelial growth factor/vascular permeability factor (VEGF/VPF)
originating from the follicle or corpus luteum may be a physiological
regulator of ovulation and neovascularization of luteinizing tissue, as
well as a pathological factor in the development of ovarian
hyperstimulation syndrome (OHSS). The objective of this study was to
quantify VEGF production by human luteinized granulosa cells in vitro and
to determine if gonadotrophin stimulates VEGF production directly and/or
indirectly via enhanced synthesis of progesterone. In study 1, luteinized
granulosa cells collected from women undergoing ovarian stimulation for
in-vitro fertilization were cultured in the presence and absence of human
chorionic gonadotrophin (HCG; 100 ng/ml) and/or low density lipoprotein
(LDL; 100 microg protein/ml). In study 2, the progesterone synthesis
inhibitor trilostane (250 ng/ml) and/or a progesterone receptor antagonist
ZK137.316 (3.2 microM) were also added. Medium was harvested on days 1, 3,
5, 7 and 9 of culture and assayed for VEGF and progesterone. Results of
study 1 were divided into two categories based on control concentrations of
VEGF on day 1: 'low producers' (n = 6; <750 pg VEGF/ml) and 'high
producers' (n = 5; >1000 pg VEGF/ml; P < 0.01). VEGF concentrations
in cultures of both low and high producers increased (P < 0.01) from day
1 to maximal values on day 3, then steadily declined through to day 9.
Chronic exposure to LDL or HCG increased (P < 0.05) VEGF concentrations
in cultures of low producers by day 3 and day 5 respectively. In contrast,
LDL did not alter VEGF concentrations in cultures of high producers and HCG
did not increase VEGF concentrations until day 7. Nevertheless, acute
exposure to HCG beginning on day 7 increased (P < 0.05) VEGF
concentrations 3-fold in cultures of low or high producers. In study 2,
trilostane treatment decreased (P < 0.05) progesterone concentrations by
91% on day 1 of culture but had no effect on VEGF concentrations on any
day. ZK137.316 alone or with trilostane did not affect VEGF synthesis.
These results suggest that VEGF production by luteinized granulosa cells is
enhanced by gonadotrophin (HCG) independent of gonadotrophin-stimulated
progesterone synthesis. These data are consistent with the hypothesis that
the exacerbation of OHSS in early pregnancy is mediated by the CG
stimulation of luteal VEGF production.
相似文献
90.
Jintanat Ananworanich Leigh Anne Eller Suteeraporn Pinyakorn Eugene Kroon Somchai Sriplenchan James LK Fletcher Duanghathai Suttichom Christopher Bryant Rapee Trichavaroj Peter Dawson Nelson Michael Nittaya Phanuphak Merlin L Robb 《Journal of the International AIDS Society》2017,20(1)
Introduction : The extent of viral replication during acute HIV infection (AHI) influences HIV disease progression. However, information comparing viral load (VL) kinetics with and without antiretroviral therapy (ART) in AHI is limited. The knowledge gained could inform preventive strategies aimed at reducing VL during AHI and therapeutic strategies to alter the viral kinetics that may enhance the likelihood of achieving HIV remission. Methods : The analysis utilized VL data captured during the first year of HIV infection from two studies in Thailand: the RV217 study (untreated AHI, 30 participants and 412 visits) and the RV254 study (treated AHI, 235 participants and 2803 visits). Fiebig stages were I/II (HIV RNA+, HIV IgM−) and Fiebig III/IV (HIV IgM+, Western blot‐/indeterminate). Data were modelled utilizing spline effects within a linear mixed model, with a random intercept and slope to allow for between‐subject variability and adjustment for the differences in variability between studies. The number of knots in the quadratic spline basis functions was determined by comparing models with differing numbers of knots via the Akaike Information Criterion. Models were fit using PROC GLIMMIX in SAS v9.3. Results : At enrolment, there were 24 Fiebig I/II and 6 Fiebig III/IV individuals in the untreated group and 137 Fiebig I/II and 98 Fiebig III/IV individuals in the treated group. Overall, the median age was 27.5 years old, most were male (89%), and CRF01_AE was the most common HIV clade (76%). By day 12 (4 days after ART in RV254), the untreated group had a 2.7‐fold higher predicted mean VL level compared to those treated (predicted log VL 6.19 for RV217 and 5.76 for RV254, p = 0.05). These differences increased to 135‐fold by day 30 (predicted log VL 4.89 for RV217 and 2.76 for RV254) and 1148‐fold by day 120 (predicted log VL 4.68 for RV217 and 1.63 for RV254) (p < 0.0001 for both) until both curves were similarly flat at about day 150 (p = 0.17 between days 150 and 160). The VL trajectories were significantly different between Fiebig I/II and Fiebig III/IV participants when comparing the two groups and within the treated group (p < 0.001 for both). Conclusions : Initiating ART in AHI dramatically changed the trajectory of VL very early in the course of infection that could have implications for reducing transmission potential and enhancing responses to future HIV remission strategies. There is an urgency of initiating ART when acute infection is identified. New and inexpensive strategies to engage and test individuals at high risk for HIV as well as immediate treatment access will be needed to improve the treatment of acute infection globally. Clinical Trial Number : NCT00796146 and NCT00796263 相似文献