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991.
Endothelial selectins are crucial for the recruitment of leukocytes into sites of inflammation. On T cells, ligands for selectins become induced upon differentiation into the effector/memory stage. Initial in vitro studies suggested a correlation between the Th1 phenotype and ligand expression, but whether this also holds true in vivo remained uncertain. We here analyzed selectin ligands on CD4+ T cells producing IFN-gamma, IL-4 or IL-10, prototypic cytokines of the Th1, Th2 and Tr1 subset, respectively. We analyzed mice infected with influenza virus, the bacterium Listeria, and the parasites Toxoplasma (all Th1 models) or Nippostrongylus (Th2 model). A link between the Th1 phenotype and ligand expression was not found in vivo. Surprisingly, the potentially regulatory IL-10-producing T cells displayed the highest frequency of ligand-positive cells in general. Within the inflamed tissues, the frequencies of P-selectin-binding cells increased in the dominant subset, either Th1 or Th2. Up-regulation was also found for E-selectin ligands during influenza, but not Nippostrongylus infection. In conclusion, conditions driving T cell polarization into either Th1 or Th2 in vivo do not affect the expression of selectin ligands, but acquisition of P-selectin binding and hence migration into inflamed tissues is boosted by an inflammatory milieu.  相似文献   
992.
To determine the levels of maturation and differentiation ofmurine CD4 single-positive (SP) T cells, we compared the secondaryresponses of staphylococcal enterotoxin A (SEA)-induced neonatalthymic, adult thymic and adult splenic CD4 SP T cell blastsprepared from whole or heat-stable antigenlow CD4 SP T cells.Proliferative responses upon re-stimulation with SEA were strongin adult splenic CD4 SP T cell blasts, but quite weak in neonatalthymic and adult thymic CD4 SP T cell blasts. SEA-induced IL-2production was weaker in neonatal thymic blasts than in theadult splenic CD4 SP T cell blasts. In contrast, SEA-inducedIL-4 production was high in neonatal thymic CD4 SP T cell blasts,and low in adult splenic and thymic CD4 SP T cell blasts. Expressionof GATA-3, that directs production of IL-4 in T cells, examinedat protein and mRNA levels, was higher in neonatal thymic cellsthan in adult thymic and splenic cells. These results suggestthat neonatal and adult thymic CD4 SP T cells in the final stageof maturation are relatively immature compared with adult splenicCD4 SP T cells. The cytokine production profile of neonatalthymic CD4 SP T cells suggests that they are inclined towardsa Th2 response.  相似文献   
993.
活动性类风湿关节炎患者sICAM-1、sVCAM-1的变化及意义   总被引:2,自引:0,他引:2  
目的 :测定活动性类风湿关节炎 (RA)患者血清中sICAM 1、sVCAM 1水平 ,探讨sICAM 1、sVCAM 1与IL 1、TNF、IFN γ及病情的关系。方法 :用酶联免疫分析法 (ELISA)检测 30例活动性RA患者与 30例健康对照者sICAM 1、sVCAM 1、IL 1、TNF、IFN γ水平。结果 :RA患者血清sICAM 1、sVCAM 1、IL 1、TNF、IFN γ水平明显高于正常对照组 (P<0 0 0 1) ,sICAM 1与IL 1、IFN γ正相关 ,与RF亦呈正相关 ,sVCAM 1与IL 1、TNF、IFN γ正相关 ,与ESR、CRP、Stock指数正相关。结论 :RA患者血清sI CAM 1、sVCAM 1水平显著升高 ,sICAM 1、sVCAM 1可能参与RA发病过程 ,sICAM 1可作为判断病情严重性的指标 ,sVCAM 1可作为观察病情活动性的指标。  相似文献   
994.
TGF- is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGB- isoforms affect TGF- production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFL-1) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TFG-1, -2, and -3. TGF- mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TGF-2 and -3 stimulated TGF-1 production significantly (p < 0.01 relative to control). TGF-1 stimulated TGF-2 production (p < 0.01 relative to control). TGF-3 was undetectable. Glucocorticoids significantly inhibited TGF-1 and -2 production and reduced expression of the upregulated TGF-1 and -2 mRNA induced by exogenous TGF-1, -2 or -3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF--stimulated cells, it was reduced by glucocorticoids. Thus, TGF- isoforms may stimulate production of various TGF- isoforms in the lung. Glucocorticoids then may block TGF- production by modulating mRNA levels and c-Jun.  相似文献   
995.
Baraitser–Winter cerebrofrontofacial syndrome (BWCS) is a rare, autosomal dominant condition that is characterized by intellectual disability, distinctive craniofacial features, structural brain abnormalities, seizures, microcephaly, hearing loss, and ocular colobomas. The first three cases were described in 1988 by Baraitser and Winter and included two siblings and an unrelated third patient. Subsequently, causative missense variants in the ACTB and ACTG1 genes were identified, with de novo occurrence in patients with the condition. Herein, we describe two adult siblings who were born to unaffected parents and who were diagnosed with BWCS in their fourth and sixth decade of life following exome sequencing performed for intellectual disability. We review the literature reports of adult patients with BWCS to document the clinical features and phenotypic variability that can occur later in life. This is the first molecularly confirmed report of germline mosaicism in BWCS and one of only a few reports to describe two BWCS patients belonging to the same family.  相似文献   
996.
《Immunity》2020,52(6):1075-1087.e8
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997.
Bacteriophage PRD1 is an icosahedral dsDNA virus with a diameter of 740 A and an outer protein shell composed of 720 copies of major coat protein P3. Spike complexes at the vertices are composed of a pentameric base (protein P31) and a spike structure (proteins P5 and P2) where the N-terminal region of the trimeric P5 is associated with the base and the C-terminal region of P5 is associated with receptor-binding protein P2. The functionality of proteins P3 and P5 was investigated using insertions and deletions. It was observed that P3 did not tolerate changes whereas P5 tolerated changes much more freely. These properties support the hypothesis that viruses have core structures and functions, which remain stable over time, as well as other elements, responsible for host interactions, which are evolutionally more fluid. The insertional probe used was the apex of exposed loop 4 of group B meningococcal outer membrane protein PorA, a medically important subunit vaccine candidate. It was demonstrated that the epitope could be displayed on the virus surface as part of spike protein P5.  相似文献   
998.
One hundred forty-nine specimens were tested in a LightCycler nested multiplex polymerase chain reaction (LCnmPCR) for Herpes simplex virus (HSV)1, HSV2, and VZV. Eighty-one were from genitourinary medicine (GUM) patients and the other 68 specimens were from other patients with skin lesions. The results were compared to a conventional multiplex nested PCR (nmPCR) using agarose gel electrophoresis. Twenty-five specimens were positive in both assays for HSV1 and 29 were positive for VZV. For HSV2 there were 27 positive in the LCnmPCR and 26 positive in the nmPCR assay. The melting temperatures (Tms) of each target were different with a mean of 84.75 degrees C for HSV1, 88.57 degrees C for HSV2, and 83.62 degrees C for VZV. The melting curves of positive specimens directly overlaid the melting curves of the positive controls in the assay. The LCnmPCR assay is a convenient alternative to conventional PCR using agarose gel electrophoresis. It improves specimen turnaround time by eliminating the need for gel electrophoresis, transillumination, and gel photography. It also shows increased sensitivity for HSV2 over our standard assay. This LCnmPCR reduces further the possibility of amplicon contamination with nested PCR protocols.  相似文献   
999.
1000.
Natural killer/T-cell lymphoma (NKTL) and peripheral T-cell lymphomas (PTCL) are prevalent in the Asian population and exhibit a high association with the Epstein-Barr virus (EBV). Moreover, differentiation of these two groups is often difficult and problematic. We investigated 35 cases of NKTL (22 nasal cases and 13 extranasal cases) and 30 cases of PTCL in terms of their clinical features, immunohistology, EBV positivity, EBV strain-type polymorphism and latent membrane protein 1 (LMP1) deletion variant distribution. Eighteen cases (82%) of nasal NKTL and seven (54%) of extranasal NKTL showed EBV positivity by EBV in situ hybridization. Fifteen cases (50%) of PTCL revealed EBV positivity. EBV strain type A was predominant in NKTL (18:5), and EBV strain types A and B were distributed evenly in PTCL (6:6). EBV-positive patients had significantly shorter survival than EBV-negative patients (P < 0.05), and EBV positivity correlated with advanced clinical stage (P < 0.05). Patients harboring type A EBV showed slightly poorer prognoses than those having type B, though it was not obviously statistically different (P = 0.07). The LMP1 deletion variant was prevalent in both NKTL (three wild-type LMP1, 15 deletion variants) and PTCL (three wild-type LMP1, eight deletion variants, two coexistent forms) patients, but did not have prognostic impact. Our results indicate that EBV acts as a negative prognostic factor in NKTL and PTCL, and that the intrinsic properties of a specific viral strain might influence the clinical behavior of these diseases.  相似文献   
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