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1.
In this study we sought to assess (1) the diagnostic value of a combined search for anti-beta(2)-glycoprotein (abeta(2)-GPIs) and anticardiolipin antibodies (aCLs) in primary (APS I) and secondary (APS II) antiphospholipid syndrome and (2) the influence of the beta(2)-GPI preparation in the ELISA's results. abeta(2)-GPI and aCL concentrations were assessed in 70 patients with APS and compared with those in 65 patients with systemic lupus erythematosus (SLE) without clinical features of APS. In APS patients (38 with APS I, 32 with APS II), the diagnosis had to have been made at least 3 years earlier; in subjects with SLE, the diagnosis had to have been made at least 5 years earlier. All serum samples were tested for abeta(2) -GPI with the use of an in-house ELISA with an abeta(2) -GPI preparation from human plasma. Samples negative for abeta(2) -GPI were controlled with 2 additional beta(2)-GPI preparations, 1 from human serum and 1 from bovine serum. In APS, abeta(2)-GPIs were more frequent than in SLE (76% and 15%, respectively; P <.0001), mainly with IgG isotype and with significantly higher levels than those found in SLE. The specificity for APS was 92% for IgG abeta(2)-GPIs and 68% for IgG aCLs. The highest association with APS was found for the combination of the 2 markers (odds ratio 29; 95% confidence interval 10-76; P <.0001). Among the APS patients, 6 were positive for aCL only and remained negative regardless of which beta 2 -GPI preparation was used; 1 patient was aCL-negative and only positive with human beta 2 -GPI. These data emphasize the heterogeneity of the APS immunologic profile and the diagnostic possibilities of both antibodies.  相似文献   
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《Vaccine》2015,33(32):3940-3946
BackgroundThis study aimed to investigate the dosage, immunogenicity and safety profile of a novel human papillomavirus (HPV) types 16 and 18 bivalent vaccine produced by E. coli.MethodsThis randomized, double-blinded, controlled phase 2 trial enrolled women aged 18–25 years in China. Totally 1600 eligible participants were randomized to receive 90 μg, 60 μg, or 30 μg of the recombinant HPV 16/18 bivalent vaccine or the control hepatitis B vaccine on a 0, 1 and 6 month schedule. The designated doses are the combined micrograms of HPV16 and 18 VLPs with dose ratio of 2:1. The immunogenicity of the vaccines was assessed by measuring anti-HPV 16 and 18 neutralizing antibodies and total IgG antibodies. Safety of the vaccine was assessed.ResultsAll but one of the seronegative participants who received 3 doses of the HPV vaccines seroconverted at month 7 for anti-HPV 16/18 neutralizing antibodies and IgG antibodies. For HPV 16, the geometric mean titers (GMTs) of the neutralizing antibodies were similar between the 60 μg (GMT = 10,548) and 90 μg (GMT = 12,505) HPV vaccine groups and were significantly higher than those in the 30 μg (GMT = 7596) group. For HPV 18, the GMTs of the neutralizing antibodies were similar among the 3 groups. The HPV vaccine was well tolerated. No vaccine-associated serious adverse events were identified.ConclusionThe prokaryotic-expressed HPV vaccine is safe and immunogenic in women aged 18–25 years. The 60 μg dosage formulation was selected for further investigation for efficacy.Clinical trials registration: NCT01356823.  相似文献   
4.
Nowadays, aerosol processes are widely used for the manufacture of nanoparticles (NPs), creating an increased occupational exposure risk of workers, laboratory personnel and scientists to airborne particles. There is evidence that possible adverse effects are linked with the accumulation of NPs in target cells, pointing out the importance of understanding the kinetics of particle internalization.In this context, the uptake kinetics of representative airborne NPs over 30 min and their internalization after 24 h post-exposure were investigated by the use of a recently established exposure system. This system combines the production of aerosolized cerium oxide (CeO2) NPs by flame spray synthesis with its simultaneous particle deposition from the gas-phase onto A549 lung cells, cultivated at the air-liquid interface.Particle uptake was quantified by mass spectrometry after several exposure times (0, 5, 10, 20 and 30 min). Over 35% of the deposited mass was found internalized after 10 min exposure, a value that increased to 60% after 30 min exposure. Following an additional 24 h post-incubation, a time span, after which adverse biological effects were observed in previous experiments, over 80% of total CeO2 could be detected intracellularly.On the ultrastructural level, focal cerium aggregates were present on the apical surface of A549 cells and could also be localized intracellularly in vesicular structures. The uptake behaviour of aerosolized CeO2 is in line with observations on cerium suspensions, where particle mass transport was identified as the rate-limiting factor for NP internalization.  相似文献   
5.
With the growing integration of non–vitamin K antagonist oral anticoagulants (NOACs) into clinical practice, questions have arisen regarding their use in special populations, including groups that may have been underrepresented in clinical trials. Patients with renal impairment, particularly in the lower echelons of renal function, are one such group. In an effort to elucidate the current evidence regarding the use of NOACs in patients with renal impairment, a systematic assessment of the literature was performed. The MEDLINE database was interrogated for studies and analyses evaluating the influence of renal function on the pharmacokinetics, pharmacodynamics, efficacy, and safety of NOACs published from January 1, 2000, through August 2, 2017. The 82 relevant publications retrieved highlight the diversity in the NOAC class regarding the impact of renal function on drug clearance, drug exposures, and clinical trial outcomes. In several large clinical trials, subgroup analyses revealed no significant differences when patients were stratified by creatinine clearance as a measure of renal function. Efficacy findings, in particular, were largely aligned with the overall population in the included studies. However, relative risks of bleeding were shown to vary, sometimes driven by changes in bleeding event rates in the comparator arm (eg, warfarin, enoxaparin). With few exceptions, minimal influence of mild renal impairment was observed on the relative efficacy and safety of NOACs. Taken together, the evidence suggests that the presence of renal impairment merits careful consideration of anticoagulant choice but should not deter physicians from appropriate use of NOACs.  相似文献   
6.

Background

Fetuses in pregnancies conceived after oocyte donation (OD) have a higher degree of antigeneic dissimilarity with the mother compared to semi-allogeneic fetuses after natural conception. We questioned whether this leads to higher level of HLA antibody formation in OD pregnancies.

Method

Uncomplicated pregnancies after OD were compared with pregnancies conceived either spontaneously or by IVF. We calculated the number of HLA- and epitope mismatches. Maternal sera were screened for HLA antibodies with ELISA; child HLA specific antibody production was determined using CDC and Luminex with single antigen beads for class I and II.

Results

A significantly (p < 0.0001) higher incidence of HLA antibody production was observed in women conceiving after OD (69%) compared to non-donor pregnancies (24–25%). The antibody formation was positively correlated with the number of fetomaternal antigen (Spearman’s rho 0.95, p < 0.0001) and epitope mismatches (Spearman’s rho 0.91, p < 0.0001). The number of HLA-DR mismatches between women and child was an independent risk factor for the production of HLA class I specific alloantibodies.

Conclusion

Women conceiving after OD have a higher risk of developing child-specific HLA antibodies; the higher the number of immunogenetic differences, the higher the chance these antibodies are formed. The high incidence of antibody production also strongly depends upon the number of HLA-DR mismatches. Despite the stronger antibody response, OD was associated with uncomplicated pregnancy in cases included in this study.  相似文献   
7.
In this study, we explored the local cytokine/chemokine profiles in patients with active pulmonary or pleural tuberculosis (TB) using multiplex protein analysis of bronchoalveolar lavage and pleural fluid samples. Despite increased pro-inflammation compared to the uninfected controls; there was no up-regulation of IFN-γ or the T cell chemoattractant CCL5 in the lung of patients with pulmonary TB. Instead, elevated levels of IL-4 and CCL4 were associated with high mycobacteria-specific IgG titres as well as SOCS3 (suppressors of cytokine signaling) mRNA and progression of moderate-to-severe disease. Contrary, IL-4, CCL4 and SOCS3 remained low in patients with extrapulmonary pleural TB, while IFN-γ, CCL5 and SOCS1 were up-regulated. Both SOCS molecules were induced in human macrophages infected with Mycobacterium tuberculosis in vitro. The Th2 immune response signature found in patients with progressive pulmonary TB could result from inappropriate cytokine/chemokine responses and excessive SOCS3 expression that may represent potential targets for clinical TB management.  相似文献   
8.
Xie L  Liu Y  Xiao Y  Tian Q  Fan B  Zhao H  Chen W 《Chest》2005,127(6):2119-2124
OBJECTIVES: To follow-up on the changes in lung function and lung radiographic pictures of severe acute respiratory syndrome (SARS) patients discharged from Xiaotangshan Hospital in Beijing (by regularly receiving examination), and to analyze retrospectively the treatment strategy in these patients. METHODS: Surviving SARS patients were seen at least twice within 3 months after discharge and underwent SARS-associated coronavirus (SARS-CoV) IgG antibody testing, pulmonary function testing, and chest radiography and/or high-resolution CT (HRCT) examinations at Chinese PLA General Hospital. The treatments received at Xiaotangshan Hospital were analyzed retrospectively and were correlated to later status. RESULTS: Positive SARS-Co virus IgG antibody results were seen in 208 of 258 patients, with 21.3% (55 of 258 patients) still having a pulmonary diffusion abnormality (D(LCO) < 80% of predicted). By comparing the 155 survivors with positive SARS-CoV IgG antibody results and D(LCO) > or = 80% predicted with the 50 patients with negative SARS-CoV IgG results, we found that 53 patients with positive SARS-CoV IgG results and a lung diffusion abnormality had endured a much longer course of fever and received larger doses of glucocorticoid, as well as higher ratios of oxygen inhalation and noninvasive ventilation treatment. For these patients, 51 of 53 patients with positive SARS-CoV IgG results and a lung diffusion abnormality underwent pulmonary function testing after approximately 1 month. D(LCO) improved in 80.4% of patients (41 of 51 patients). Of the patients with a lung diffusion abnormality, 40 of 51 patients showed lung fibrotic changes in the lung image examination and 22 patients (55%) showed improvement in lung fibrotic changes 1 month later. CONCLUSION: These findings suggest that lung fibrotic changes caused by SARS disease occurred mostly in severely sick patients and may be self-rehabilitated. D(LCO) scores might be more sensitive than HRCT when evaluating lung fibrotic changes.  相似文献   
9.
Macrophage migration inhibitory factor promotes intestinal tumorigenesis   总被引:5,自引:0,他引:5  
BACKGROUND & AIMS: The cytokine macrophage migration inhibitory factor (MIF) is expressed throughout the human gastrointestinal tract. Recently, protumorigenic activity of MIF has been described in several cancer models. Therefore, we investigated the expression and function of MIF during the early stages of intestinal tumorigenesis. METHODS: MIF messenger RNA, protein, and tautomerase activity were measured in normal intestinal mucosa and adenomas from patients with sporadic colorectal adenomas and in the adenomatous polyposis coli (Apc)Min/+ mouse model of intestinal tumorigenesis. MIF function was investigated by using VACO-235 human colorectal adenoma cells in vitro and by testing the effect of genetic deletion of Mif on ApcMin/+ mouse intestinal tumorigenesis. RESULTS: MIF expression and tautomerase activity were increased in human and ApcMin/+ mouse intestinal adenomas compared with adjacent normal mucosa. Up-regulation of MIF occurred mainly in epithelial cells (associated with an increasing grade of dysplasia), but also in stromal plasma cells. Exogenous MIF inhibited apoptosis and promoted anchorage-independent growth of VACO-235 cells (maximal at 100 ng/mL). Homozygous deletion of Mif was associated with a reduction in the number and size of ApcMin/+ mouse adenomas (P = .025 for the difference in large [>7-mm] tumors) and decreased angiogenesis (43% decrease in mean tumor microvessel density), but there was no alteration in epithelial cell apoptosis or proliferation. CONCLUSIONS: MIF expression is increased in sporadic human colorectal adenomas, and exogenous MIF drives tumorigenic behavior of epithelial cells in vitro. Mif also promotes intestinal tumorigenesis (predominantly via angiogenesis) in the ApcMin/+ mouse. Therefore, MIF is a potential colorectal cancer chemoprevention target.  相似文献   
10.
Huntington's disease (HD) is the most prevalent polyglutamine expansion disorder. HD is caused by an expansion of CAG triplet in the huntingtin (HTT) gene, associated with striatal and cortical neuronal loss. Central and peripheral metabolic abnormalities and altered insulin-like growth factor-1 (IGF-1) levels have been described in HD. Thus, we hypothesized that restoration of IGF-1-mediated signaling pathways could rescue R6/2 mice from metabolic stress and behavioral changes induced by polyglutamine expansion. We analyzed the in vivo effect of continuous peripheral IGF-1 administration on diabetic parameters, body weight and motor behavior in the hemizygous R6/2 mouse model of HD. We used 9 week-old and age-matched wild-type mice, subjected to continuously infused recombinant IGF-I or vehicle, for 14 days. IGF-1 treatment prevented the age-related decrease in body weight in R6/2 mice. Although blood glucose levels were higher in R6/2 mice, they did not reach a diabetic state. Even though, IGF-1 ameliorated poor glycemic control in HD mice. This seemed to be associated with a decrease in blood insulin levels in R6/2 mice, which was increased following IGF-1 infusion. Similarly, blood IGF-1 levels decreased during aging in both wild-type and R6/2 mice, being significantly improved upon its continuous infusion. Although no significant differences were found in motor function in R6/2-treated mice, IGF-1 treatment highly improved paw clasping scores. In summary, these results suggest that IGF-1 has a protective role against HD-associated impaired glucose tolerance, by enhancing blood insulin levels.  相似文献   
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