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91.
目的探讨宫内炎症暴露对早产儿固有免疫应答的影响。方法 2013年6月至2014年6月出生、胎龄35周的早产儿47例纳入本研究。依据胎盘病理检查结果,将早产儿分为宫内炎症阳性组和阴性组。采用Ficoll密度梯度离心法和贴壁黏附法分别获得脐血单个核细胞以及单核细胞。用内毒素(LPS,100 ng/ml)刺激单个核细胞12 h后,流式细胞术(PCR)检测CD14+单核细胞HLA-DR的表达量以及CD3+CD4+/CD3+CD8+的比例。用LPS(100 ng/ml)刺激单核细胞6 h后,Real-Time PCR检测单核细胞IL-1β、IL-6、IL-10、TNF-αm RNA表达量的变化。ELISA检测脐血以及单核细胞培养上清液中IL-1β、IL-6、IL-10和TNF-α水平。结果宫内炎症阳性组脐血血浆IL-6水平高于宫内炎症阴性组,差异有统计学意义(P=0.001)。LPS刺激后,两组单核细胞IL-1β、IL-6、IL-10、TNF-αm RNA表达量及培养上清液中蛋白水平均显著升高,与刺激前比较差异均有统计学意义(P0.05);但两组间比较差异均无统计学意义(P0.05)。LPS刺激后,宫内炎症阳性组CD14+单核细胞HLA-DR表达量显著降低,而宫内炎症阴性组则显著升高,与刺激前比较差异均有统计学意义(P0.05);且阳性组HLA-DR表达量显著低于阴性组(P=0.002)。结论宫内炎症暴露并不影响早产儿脐血单核细胞对LPS的应答反应水平,但可抑制单核细胞激活后主要抗原递呈受体的表达。  相似文献   
92.
Mutations in SH2D1A, encoding the intracellular adaptor signaling lymphocyte activation molecule associated protein (SAP), are associated with X‐linked lymphoproliferative disease type 1 (XLP1). We identified a novel hemizygous SH2D1A c.49G > A (p.E17K) variant in a 21‐year‐old patient with fatal Epstein‐Barr virus infection–associated hemophagocytic lymphohistiocytosis. Cellular and biochemical assays revealed normal expression of the SAP variant protein, yet binding to phosphorylated CD244 receptor was reduced by >95%. Three healthy brothers carried the SH2D1A c.49G > A variant. Thus, data suggest that this variant represents a pathogenic mutation, but with variable expressivity. Importantly, our results highlight challenges in the clinical interpretation of SH2D1A variants and caution in using functional flow cytometry assays for the diagnosis of XLP1.  相似文献   
93.
Summary Effects of four days of intense physical activity on serum concentrations of total triglycerides, total cholesterol and apolipoproteins A-I, A-II, and B were studied in 35 well-trained young men. Serum total triglyceride levels decreased to 70% of baseline levels after 24 h, and fell further to 50% of baseline levels after 4 days. Serum levels of total cholesterol fell steadily to about 80% of baseline levels on the 4th day. Apo-B levels fell to 85% of baseline levels after 24 h, and remained at that level. Apo A-I fell to about 90%, and apo A-II to about 80% of baseline levels, causing a significant increase in the ratio of apo A-I to apo A-II. The intraindividual changes in apo B were positively correlated to changes in cholesterol during the first day (r=0.60). The changes in apo A-I and apo A-II had no significant correlation with changes in total cholesterol or triglycerides, or with one another, suggesting that apo A-I and apo A-II are metabolized independently during conditions of hard physical exercise.  相似文献   
94.
AIMS: The aims were to estimate case fatality and survival rates, standardized mortality ratio (SMR), and independent prognostic factors for survival, in a population-based cohort of progressive encephalopathy (PE) patients. METHODS: We divided onset of disease into neonatal and postneonatal groups and aetiology into metabolic (n=55), neurodegenerative (n=27) and HIV encephalopathy (n=2) groups. Case fatality was the number of deaths divided by the number of patients. Cumulative survival probability at 10 years of follow-up and independent risk factors for mortality were analyzed using the Kaplan-Meier survival curve and the Cox model. RESULTS: Case fatality was 36.9% and the mean and median follow-up times were 3109 and 2887 days. At 1 and 10 years, the cumulative probability of survival was 81% and 66%. Neonatal onset showed increased risk of death compared to postneonatal onset (RR 3.0; 95% CI 1.4-6.2). Metabolic aetiology showed increased risk of death compared to other aetiology (RR 1.25; 95% CI 1.10-1.46). The SMR of 37.7 for boys and 23.8 for girls was significantly increased (p<0.001) compared to the total Norwegian population stratified by gender and age. CONCLUSIONS: Children with PE showed a vast excess in mortality compared to the general population stratified by gender and age. Neonatal presentation and metabolic aetiology were the most significant factors for increased risk of death.  相似文献   
95.
96.
Sexually transmitted infections (STIs) remain major public health problems globally. Appropriate laboratory diagnosis of STIs is rare in Ukraine. We investigated the prevalence of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) using the US FDA‐approved Aptima Combo 2 and Aptima TV assays and compared the results with the conventional routine diagnostic tests (CDTs) in Ukraine. Urogenital swabs from consecutive mostly symptomatic females (n = 296) and males (n = 159) were examined. The prevalences were as follows: 10% (n = 47) of TV, 5.3% (n = 24) of CT and 1.5% (n = 7) of NG. The specificity of some CDTs was high, for example, 100% for NG culture, TV IgG ELISA, CT IgM ELISA and CT microscopy, but lower for other CDTs, that is, from 44% to 99.8%. The sensitivity of all CDTs was suboptimal, that is, 71% (n = 5) for NG microscopy, 57% (n = 4) for NG culture, 53% (n = 8) for CT IgG ELISA, 33% (n = 1) for TV IgG ELISA, 28% (n = 13) for TV microscopy, 25% (n = 1) for CT IgA ELISA, 20% (n = 3) for CT IgM ELISA and 0% (n = 0) for CT microscopy. The prevalences of particularly TV and CT were high, but substantial also for NG, in Ternopil, Ukraine. The sensitivities of all CDTs were low, and widespread implementation of validated, quality‐assured and cost‐effective molecular diagnostic STI tests in Ukraine is imperative.  相似文献   
97.
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG repeat expansion in the first exon of the androgen receptor (AR) gene. Disease-associated alleles (37-66 CAGs) change in length when transmitted from parents to offspring, with a significantly greater tendency to shift size when inherited paternally. As transgenic mice carrying human AR cDNAs with 45 and 66 CAG repeats do not display repeat instability, we attempted to model trinucleotide repeat instability by generating transgenic mice with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions in their genomic context. Studies of independent lines of AR YAC transgenic mice with CAG 45 alleles reveal intergenerational instability at an overall rate of approximately 10%. We also find that the 45 CAG repeat tracts are significantly more unstable with maternal transmission and as the transmitting mother ages. Of all the CAG/CTG repeat transgenic mice produced to date the AR YAC CAG 45 mice are unstable with the smallest trinucleotide repeat mutations, suggesting that the length threshold for repeat instability in the mouse may be lowered by including the appropriate flanking human DNA sequences. By sequence-tagged site content analysis and long range mapping we determined that one unstable transgenic line has integrated an approximately 70 kb segment of the AR locus due to fragmentation of the AR YAC. Identification of the cis - acting elements that permit CAG tract instability and the trans -acting factors that modulate repeat instability in the AR YAC CAG 45 mice may provide insights into the molecular basis of trinucleotide repeat instability in humans.   相似文献   
98.
The clinicopathological associations of 33 singleton infants who died with intraventricular haemorrhage (IVH) without hyaline membrane disease (HMD) ('IVH only') were compared with those of 39 infants who died with IVH+HMD over the same gestation range in order to determine what factors other than those related to HMD may contribute to the pathogenesis of IVH. The incidence of 'IVH only' was inversely related to gestational age in the Hammersmith birth population, whereas the incidence of IVH+HMD rose to a peak at 28-29 weeks' gestation. Infants with 'IVH only' lived longer on average than those with IVH+HMD despite a lower birthweight and shorter gestation. Infants who died in the first 12 hours from 'IVH only' had suffered severe birth asphyxia but in those who died later the main symptom was recurrent apnoea. Fewer infants with asphyxia but in those who died later the main symptom was.recurrent apnoea. Fewer infants with 'IVH only' were given alkali therapy or were connected to the ventilator as compared to those with IVH+HMD, but there were no differences in alkali therapy in those who lived for 12 hours or more. In the 'IVH only' group there was a high incidence of haemorrhage from other sites and of bacterial infections. It is suggested that, in the absence of HMD, extreme immaturity is the main factor determining the occurrence of IVH. Birth asphyxia, apnoeic attacks, haemorrhage, and infections may play subsidiary roles, possibly through development of metabolic acidosis.  相似文献   
99.
Stephensen H  Tisell M  Wikkelsö C 《Neurosurgery》2002,50(4):763-71; discussion 771-3
OBJECTIVE: To examine whether a transmantle pressure gradient exists in adult patients with communicating and noncommunicating hydrocephalus. METHODS: Ten patients participated in the study. The mean patient age was 57 +/- 18 years (range, 20-80 yr); seven patients had communicating hydrocephalus, and three had noncommunicating hydrocephalus. Microsensors were used to measure the intracranial pressure (ICP), for 17 to 24 hours during sleeping and waking periods, in the right lateral ventricle (ICP(IV)) and in the subarachnoid space (ICP(SAS)) over the right cerebral convexity simultaneously. Patient activities and body positions were documented. The hydrostatic pressure difference between the two sensors was calculated from cranial x-rays for four basic body positions and compared with the actual body positions of the patients and the measured difference between the two sensors. For three 10-minute periods, the exact transmantle pressure gradient was calculated for each patient as ICP(IV) - ICP(SAS), adjusted for the hydrostatic pressure difference. RESULTS: The measured pressure difference between the two sensors was always within the limits of the maximal possible hydrostatic pressure difference, and it correlated well with the expected difference for the various body positions: mean correlation coefficient, 0.79 +/- 0.10 (range, 0.65-0.92). The exact mean transmantle pressure was -0.01 +/- 0.24 mmHg (range, -0.4 to 0.4 mmHg). ICP waves caused by cardiac pulse, respiration, and B waves were identical in both spaces. CONCLUSION: This study demonstrates no factual support for existence of a transmantle pressure gradient in nonacute communicating or noncommunicating hydrocephalus.  相似文献   
100.
In order to establish a series of provocation tests to evaluate the integrity of the sperm cAMP pathway, manganese (Mn), 2-deoxyadenosine (DEA) (via adenylyl cyclase), and methyl-isobutyl-xanthine (MIX) (via phosphodiesterase) were tested for their capacity to activate the progressive motility of human sperm. Optimal responses were obtained using washed sperm previously incubated for 3 hours in substrate-poor medium (Hepes-buffered saline). Longer periods of incubation required the presence in addition of an energy substrate such as glucose. Exposure of sperm to seminal plasma for 24 hours prior to washing attenuated the responsiveness of the sperm to the different activators. Preliminary studies on the activation of the progressive motility of washed sperm from four normozoospermic men under fertility investigation, prepared under identical conditions, revealed differences in the pattern of response which may have pathophysiological relevance.  相似文献   
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