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151.
Inflammatory events during Leishmania braziliensis infection in mice were investigated. Large lesions were directly correlated with the inflammatory reaction but not with parasite burden. Different L. braziliensis strains induce different paces of chemokine expression patterns, leading to diverse cell recruitment and differential inflammatory responses.  相似文献   
152.
Background/objective: Approximately 10% of small for gestational age (SGA) infants fail to catch up. The relationship between postnatal growth and placental pathology in SGA infants remains unclear. Our aim was to assess the involvement of placental pathology in postnatal growth of SGA infants.

Methods: We retrospectively evaluated placental pathology and postnatal growth in single-pregnancy infants born after 37 gestational weeks in our institution, with both birth weight and length below ?2 standard deviation scores (SDS) of the normal weight and length. “Catch-up” was defined as height reaching ?2 SDS before the second birthday. Pathology of the placenta was classified into: abnormality due to maternal factors or fatal factors, villitis of unknown etiology (VUE), other abnormalities and no abnormality.

Results: Of the 33?084 infants, 142 met our criteria and 49 of them had analyzable data. The overall catch-up rate was 84%. Catch-up growth took place in all infants with no placental abnormality and only 57% of infants with abnormality due to fatal factors. There was no significant relationship between catch-up rate and other factors.

Conclusion: Placental pathology is associated with postnatal growth in SGA children born at term. Placental abnormality due to fetal factors is related to poor catch-up rate.  相似文献   
153.
Long‐read sequencing can resolve regions of the genome that are inaccessible to short reads, and therefore are ideal for genome‐gap closure, solving structural rearrangements and sequencing through repetitive elements. Here we introduce the Xdrop technology: a novel microfluidic‐based system that allows for targeted enrichment of long DNA molecules starting from only a few nanograms of DNA. Xdrop is based on the isolation of long DNA fragments in millions of droplets, where the droplets containing a target sequence of interest are fluorescently labeled and sorted using flow cytometry. The final product from the Xdrop procedure is an enriched population of long DNA molecules that can be investigated by sequencing. To demonstrate the capability of Xdrop, we performed enrichment of the human papilloma virus 18 integrated into the genome of human HeLa cells. Analysis of the sequencing reads resolved three HPV18‐chr8 integrations at base‐pair resolution, and the captured fragments extended up to 30 kb into the human genome at the integration sites. Further, we enriched the complete TP53 locus in a leukemia cell line and could successfully phase coexisting mutations using PacBio sequencing. In summary, our results show that Xdrop is an efficient enrichment technology for studying complex genomic regions.  相似文献   
154.
Persistent infection of SARS coronavirus in colonic cells in vitro   总被引:5,自引:0,他引:5  
Severe acute respiratory syndrome coronavirus (SARS-CoV) can produce gastrointestinal symptoms. The intestinal tract is the only extrapulmonary site where viable viruses have been detected. This study examined seven established human intestinal cell lines, DLD-1, HCT-116, HT-29, LoVo, LS-180, SW-480 and SW-620, for their permissiveness to SARS-CoV infection. The results showed that only LoVo cells were permissive to SARS-CoV infection as evident by positive findings from indirect immunofluorescence staining for intracellular viral antigens, in situ hybridization for intracellular viral RNA, and electron microscopy for intracellular viral particles. In contrast to Vero cells, SARS-CoV did not produce cytopathic effects on LoVo cells. However, LoVo cells were found to be highly permissive for productive infection with a high viral titre (>3 x 10(7) viral copies/ml) produced in culture supernatant following a few days of incubation. SARS-CoV established a stable persistent chronic infection that could be maintained after multiple passages. Being a cell line of human origin, LoVo cells could be a useful in vitro model for studying the biology and persistent infection of SARS-CoV. Our results on the expression of angiotensin-converting enzyme 2 (ACE2), a recently identified cellular receptor for SARS-CoV, in these cell lines indicated that it might not be the sole determinant for cells to be susceptible to SARS-CoV infection.  相似文献   
155.
156.
157.
Previous studies have suggested that CD4+ T lymphocytes shift from the Th1 type to the Th2 type during disease progression in patients with the human immunodeficiency virus type-1 (HIV-1). In the present study, we used a modified method that allowed a direct measurement of intracellular cytokines in CD4+ CD8- T cells. A total of 48 HIV-1-infected (HIV+) and 16 HIV-1-uninfected (HIV-) individuals were studied. The percentages of CD4+ CD8- T cells producing interleukin-2 (IL-2), interferon-gamma (IFN-gamma), interleukin-4 (IL-4), or interleukin-5 (IL-5) in HIV+ and HIV- subjects were 23.6% versus 34.9% (P < 0.01), 13.7% versus 13.2%, 1.3% versus 1.0%, and 1. 2% versus 0.9%, respectively. The population of IL-2-producing cells decreased proportionately with reductions in CD4 counts (< 200/mm3, 200-500/mm3, and > 500/mm3 to 18.0%, 23.5%, and 30.5%, P < 0.05, respectively). There was an inverse correlation between the percentage of IL-2-producing cells and plasma viral load (r = - 0. 446, P < 0.05). However, the percentages of CD4+ CD8- T cells producing other cytokines were not different between HIV+ and HIV-. Our cross-sectional study demonstrated a decrease in IL-2-producing cells but not the Th1 to the Th2 shift in the CD4+ CD8- T cell population in the moderate and advanced stages of HIV-1-infection.  相似文献   
158.
BACKGROUND: Various surgical and non-surgical treatment options are available for women with congenital vaginal agenesis. We report results of vaginal dilation therapy delivered by a multi-disciplinary team as first line treatment for vaginal agenesis. METHODS: Twenty-six women were recruited into a prospective observational study: 18 had Mayer-Rokitansky-Kuster-Hauser syndrome (MRKH) and 8 had Complete Androgen Insensitivity Syndrome (CAIS). All women underwent a vaginal dilation programme co-ordinated by a clinical nurse specialist with input from a clinical psychologist. Vaginal length was compared to a normal reference range, and psycho-sexual questionnaires were completed before and after therapy. RESULTS: Twenty-one (81%) patients completed the programme. Seventeen of these 21 (81%) were sexually active without any reported difficulties, whereas 4 were on a maintenance regime. In those who completed the programme the mean vaginal length increased from 4.0 to 8.5 cm and 86% achieved a vaginal length within the normal range. Subjective appraisal of vaginal size recorded that the number of women who reported that their vaginal size was 'more or less normal' increased from 1 to 12 following treatment. Questionnaire scores for sexual satisfaction and sexual depression improved in the CAIS group but did not alter significantly in the MRKH group. CONCLUSION: Non-surgical dilation delivered by a multi-disciplinary team is an effective alternative to vaginal surgery and usually normalizes vaginal length.  相似文献   
159.
Salmonella enterica subsp. enterica serotype Enteritidis is not readily subtyped beyond the level of phage type (PT). Pulsed field gel electrophoresis (PFGE) is generally acknowledged to be the most discriminating typing method for Salmonella, but only a restricted variety of PFGE types has been described for S. enterica serotype Enteritidis. In the present study, a modification of the SE-AFLP typing method was used to investigate both outbreak and apparently sporadic isolates of S. enterica serotype Enteritidis belonging to different PTs and/or PFGE types. The method proved to be as discriminatory as PFGE when combined with phage typing, and provided subtyping data consistent with epidemiological information. Although the modified SE-AFLP typing method did not prove to achieve a superior discriminatory ability in resolving clusters, it has a high enough throughput for use in outbreak investigations. This method can be used in combination with other typing methods to obtain epidemiologically relevant subtyping data on S. enterica serotype Enteritidis.  相似文献   
160.
Background: Hepatocyte growth factor (HGF) is a member of the adipocytokine family; it is implicated in tissue repair, regeneration, and angiogenesis. Several studies have reported that the HGF plays important role in obesity and cardiovascular disease.

Aim: This study examines whether HGF and its phenotypic correlations with obesity and blood pressure (BP), in healthy individuals, are due to shared genetic or common environmental factors.

Subjects and methods: Body mass index (BMI), waist-to-hip ratio (WHR), BP, and HGF plasma concentrations were measured in a sample of 733 individuals belonging to 248 pedigrees.

Results: The most significant phenotypic correlations were found among HGF, WHR, and systolic BP (p < 0.001). Analysis of the familial aggregation revealed that parent–offspring and sibling correlations in HGF levels, adjusted for age, age2, and sex, were statistically highly significant (p < 0.001). Variance decomposition analysis showed that when adjusted for potential covariates, 48.4% of the HGF variation was due to putative genetic factors. The genetic correlations between all pairs of studied traits (HGF, WHR, and SBP) were statistically significant (p < 0.02) and ranged between 0.23 ± 0.07 and 0.40 ± 0.07. However, correlation between WHR and BP becomes non-significant after adjustment for HGF.

Conclusions: The results provide evidence that putative genetic factors involved in regulation of HGF variation contribute also significantly to variation of the obesity and BP. It is possible that the familial resemblance for WHR and the SBP correlation in the studied sample is affected substantially by genetic factors regulating circulating HGF levels.  相似文献   
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