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121.

Background  

Antiphospholipid syndrome (APS) has been often associated to RPL since 1980 and some reports in the Literature rarely described antibodies to factor XII in patients with APS.  相似文献   
122.
OBJECTIVE: To compare nasal symptomatology and function and local concentrations of estradiol (E2), estradiol receptor (ERalpha), vasoactive intestinal peptide (VIP), substance P (SP) and neuropeptide Y (NPY) in nasal biopsies of 20 postmenopausal women complaining of paradoxical nasal stuffiness before and after treatment with intranasal or transdermal E2. DESIGN: Twenty healthy postmenopausal women willing to start hormone therapy (HT) were allocated to one of two groups, using a computer-generated randomization list.Ten postmenopausal women were treated with transdermal 17beta-estradiol 50 microg daily plus nomegestrole acetate 5 mg/day for 12 days per 28-day cycle for 6 months (Group A). Ten postmenopausal women were treated with intranasal 17beta-estradiol 300 microg/day (one spray delivery of 150 microg per nostril) plus nomegestrole acetate 5 mg/day for 12 days per 28-day cycle for 6 months (Group B). Fourteen fertile women undergoing nasal mucosa biopsy during plastic surgery were used as controls for the immunohistochemical evaluation (Group C).All women in groups A and B underwent evaluation of nasal stuffiness score, mucociliary transport time, rhinoscopy, and active anterior rhinomanometry at the beginning of the study and after, VIP, SP, and 6 months of HT. Nasal biopsies and evaluation of local concentrations of E2, ERalpha NPY were performed in groups A and B before and after 6 months of HT and in group C. RESULTS: Both intranasal and transdermal HT improve nasal symptomatology and nasal mucosa appearance and reduce mean mucociliary transport time. The effectiveness of intranasally administered therapy at improving nasal function is significantly better than transdermal therapy. In comparison with premenopausal controls, untreated postmenopausal women of group A and B showed significantly decreased immunopositivity for E2, ERalpha, and SP. HT induced a significant increase in E2, ERalpha, VIP, and SP and a decrease in NPY immunopositivity. Intranasal therapy was associated with a significantly higher immunopositivity for VIP and SP. CONCLUSIONS: HT improves nasal function and symptomatology in postmenopausal women with paradoxical nasal stuffiness, modulating nasal mucosa function through an action on cholinergic, adrenergic, and sensory peptides. Intranasally administered HT is more effective at improving nasal function than transdermal HT.  相似文献   
123.
The gene encoding the major envelope glycoprotein (gp51) with its signal sequence, represented by an additional NH2-terminal 33-residue amino acid sequence of bovine leukemia virus (BLV), was inserted into a baculovirus transfer vector. A recombinant virus expressing a secreted gp51 protein in insect cells was isolated. The recombinant gp51 expressed was characterized by using an anti-BLV monoclonal antibody by both Western blotting analysis and enzyme-linked immunosorbent assay (ELISA). The secreted gp51 was used as an antigen, and an ELISA with recombinant gp51 (rgp51) was developed for the detection of BLV antibodies. This new procedure was compared with a previous ELISA method for the detection of BLV antibodies and an agar gel immunodiffusion test performed with an unpurified BLV antigen preparation. The comparative testing of field samples showed that the ELISA with rgp51 is more specific and also suitable for the testing of pooled sera.  相似文献   
124.
There is experimental evidence that the CD4 molecule participates in the antigen-driven activation of T cells expressing this surface glycoprotein. Whether CD4, a member of the immunoglobulin supergene family, acts as a ligand-binding molecule and/or is directly involved in the activation pathway has yet to be established. In this study, we show that human CD4+ lymphocytes can be activated by exposure to the anti-CD4 monoclonal antibody (mAb) B66. Normal peripheral blood CD4+ cells were induced to proliferate and to synthesize interleukin 2 (IL2) by the antibody. The specificity of the antibody stimulatory activity was tested by using IL2-producing clones bearing either CD4 or CD8 on their surface. IL2 production was induced by mAb B66 in CD4+, but not CD8+, clones, whereas both types of clones responded to stimulation by the anti-CD3 mAb Leu-4. Despite its unique stimulatory activity, mAb B66 shared with other anti-CD4 antibodies the ability to inhibit the specific cytolytic activity of CD4+ effector cells. These results clearly indicate that cross-linking of surface CD4 molecules with appropriate antibodies can fully activate CD4+ lymphocytes. Whether the natural ligand for CD4 can trigger this activation pathway remains to be defined.  相似文献   
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BALB/c mice injected at birth with semi-allogeneic F1 spleen cells become tolerant to alloantigens as shown by their CTL unresponsiveness to the corresponding alloantigen and the persistence of donor F1 cells into the BALB/c host. Moreover, these mice develop a transient systemic lupus erythematosis-like autoimmune syndrome characterized by splenomegaly, glomerulonephritis, thrombocytopenia and abnormal serological findings, such as several autoantibodies and IgG1 hypergammaglobulinemia. Recent studies done in our laboratory have shown that donor F1 B cells persisting in the host are responsible for the production of autoantibodies and must be activated in vivo by the host CD4+ T lymphocytes in a MHC class II-restricted fashion. In the present work, we have focused our attention on the ability of splenic CD4+ T cells recovered at different periods from BALB/c mice injected at birth with (CBA/Ca × BALB. Ighb) Fl spleen cells to interact with and activate F1 semi-allogeneic spleen cells in vitro. We show that (i) only CD4+ T cells from 2- and 3-week-old tolerant BALB/c mice preferentially produce IL-4 and IL-5 in response to a F1 semi-allogeneic in vitro stimulation, (ii) CD4+ T cells purified from 3-week-old tolerant BALB/c mice are able to induce in vitro IgG and IgM production by F1 B cells. Taken together, these results strongly suggest that host CD4+ T cells, belonging to the TH2 subset progressively lose their reactivity towards the F1 semi-allogeneic persistent B cells, reaching a state of unresponsiveness that correlates with the disappearance of serum autoantibodies and autoimmune pathology.  相似文献   
128.
Renal function in relation to three candidate genes in a Chinese population   总被引:3,自引:0,他引:3  
We recently found in a white population that the genes encoding angiotensin-converting enzyme (ACE, I/D polymorphism), -adducin (Gly460Trp), and aldosterone synthase (–344C/T) jointly influence renal function. We therefore investigated in a Chinese population the associations between the serum concentrations of creatinine and uric acid and these three genetic polymorphisms. We genotyped 471 ethnic Han Chinese subjects from 125 nuclear families recruited in northern China via random population sampling (75%) and at specialized hypertension clinics (25%). We performed population-based and family-based association analyses using generalized estimating equations (GEE) and quantitative transmission disequilibrium test (QTDT), respectively, while controlling for covariables. The participants were 39.7 years old and included 235 women (49.9%). The blood pressure measured at the subjects homes averaged 126/80 mmHg. Mean values were 71 µmol/l for serum creatinine, 111 ml min–1 1.73 m–2 for calculated creatinine clearance, and 236 µmol/l for serum uric acid. With adjustment for covariables, GEE analyses of single genes demonstrated that serum uric acid, but not serum creatinine, was positively associated with the ACE D allele. Serum uric acid concentrations were 15.8 µmol/l (95% confidence interval 3.3–28.2) and 25.7 µmol/l (11.1–40.2) higher in DD homozygotes than in ID and II subjects, respectively. Further GEE analyses of the three genes combined showed that the association between serum uric acid and the ACE polymorphism was confined to carriers of the -adducin Gly and/or aldosterone synthase C alleles. Sensitivity analyses in parents and offspring separately as well as QTDT analyses were confirmatory. Among 114 informative offspring carrying the -adducin Gly allele serum uric acid was significantly and positively associated with the transmission of the ACE D allele (=20.7 µmol/l). In conclusion, the present study extends our previous findings on the combined effects of the three candidate genes and supports the concept that these genetic polymorphisms jointly influence renal function.  相似文献   
129.
Soluble and phagocytic stimuli released PAF-acether from PMN leucocytes, as determined by chromatography and bioassay by platelet aggregation. The same material caused aggregation of human and rabbit PMN leucocytesin vitro which was inhibited by ETYA and PGI2. PGI2 also inhibited PAF-acether release by PMN leucocytes and,in vivo, PGI2 abolished not only PAF-acether-induced, but also immune complex or C5a-induced thrombocytopenia and neutropenia in rabbits. These data suggest that PAF-acether may be involved in activation of both platelets and PMN leucocytesin vivo.  相似文献   
130.
From the second half of the eighties, the cases of tuberculosis (TBC) in Italy have been constantly increasing. The increase in TBC cases in developed countries is related to different factors, including HIV epidemic and increased number of immigrants from countries with high TBC incidence and important socio-economic problems. Compared with adults few children with TBC were homeless or coinfected with HIV, nonetheless the children lived frequently in low socioeconomic status and consequently high risk of being uninsured and with adults at risk for tuberculosis (immediate relative, household members, or recently immigrated). An epidemiologic study was carried out, in order to evaluate the impact of TBC infection in immigrant children. From January 2001 to December 2002, Mantoux test (5 IU) was performed in immigrant children hospitalized or followed in two children hospitals. They included 228 children: mean age 4 years (range 1 month to 15 years). The patients came from: South America (44%) (especially from Ecuador), from Africa (20%), from Eastern Europe (19%), (especially from Middle East and North Africa), from Far East (17%). In 30 cases (13,2%) Mantoux test was positive. Among these latter, 21 presented latent infection, whereas another 9 had tuberculous disease with pulmonary localization and one of them associated with cervical adenopathy. In the study period, among all children (4426) admitted the two Units, the prevalence of tuberculous disease was 2,5% in immigrant children compared 0.2% in native children. Accurate epidemiologic monitoring, further clinical studies aimed at highlighting TBC peculiar aspects in children, and adequate therapy can lead to TBC control in the immigrant children.  相似文献   
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