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121.
There were many reports of longitudinal changes in the causative organisms of neonatal sepsis in Western countries but few in Asia. We aimed to study longitudinal trends in the epidemiology of neonatal sepsis at Seoul National University Children's Hospital (SNUCH), a tertiary center in Korea, and compared the results to previous studies of Western countries. The medical records of all of the neonates who were hospitalized at SNUCH from 1996 to 2005 with positive blood cultures were reviewed. We also compared the findings to previous 16-yr (1980-1995). One hundred and forty-nine organisms were identified in 147 episodes from 134 infants. In comparison with the previous 16-yr studies, there was a decrease in the number of Escherichia coli infections (16.2% vs 8.7%: odds ratio [OR] 0.495; 95% confidence interval [CI], 0.255-0.962; P = 0.035), but an increase in Staphylococcus aureus (16.6% vs 25.5%: OR 1.720; 95% CI, 1.043-2.839; P = 0.033) and fungal infections (3.3% vs 18.7%: OR 6.740; 95% CI, 2.981-15.239; P < 0.001), predominantly caused by Candida species. In conclusion, the incidence of sepsis caused by E. coli decreases, but S. aureus and fungal sepsis increases significantly. Compared with Western studies, the incidence of sepsis caused by S. aureus and fungus has remarkably increased.  相似文献   
122.
123.
It was explored if the speed with which an individual learns to deal with new environments and challenges can be predicted on the basis of his/her brain's response to irrelevant (repeating) and novel auditory stimuli. In this study, 26 subjects threw 30 light-weight balls at a target with and without vision-distorting goggles. The horizontal displacement from a bull's-eye target was measured and the rate and degree of adaptation were computed. The adaptation parameters were correlated with evoked and event-related potential (EP/ERP) measures of the subject's ability to suppress irrelevant information and respond to novel stimuli. Only a weak (or a trend to) correlation was found between the behavioral adaptation and some of the EP/ERP measures. The correlations were limited to EP parameters in the 100 to 200 ms post-stimulus range reflecting the ability to suppress irrelevant information. Thus we conclude that the speed with which an individual adapts to a new environment is at best weakly correlated with brain activity associated with stimulus memory and classification.  相似文献   
124.
We have previously demonstrated, in the collagen-induced arthritis model (CIA), that repetitive injections of immature bone-marrow-derived dendritic cells (iDCs) induce the expansion of a population of CD4CD49b-expressing cells, and that their adoptive transfer results in protection against CIA in a prophylactic setting. However, the in vivo mechanism responsible for their expansion, as well as their therapeutic potential in established disease remains to be defined. In the present study, we show that expression of the MHC class II molecules on iDCs is required for their expansion thus identifying these cells as MHC class II-restricted T cells. Using adoptive transfer of Thy1.1 positive cells, it is shown that iDC-induced CD4+CD49b+ T cells home to the lymph nodes draining the inflamed tissue. The high immunomodulatory potential of these cells was underscored following their adoptive transfer in a model of contact hypersensitivity. Finally, we assessed and compared the therapeutic potential of iDC-inducible CD4+CD49b+ T cells with that of iDCs in established CIA. Repetitive injections of iDCs in arthritic mice failed to decrease the severity of established disease. In contrast however, a single injection of iDC-induced CD4+CD49b+ T cells reversed clinical symptoms of arthritis and provided long-lasting protection. Together, our data indicate that iDC-induced CD4+CD49b+ T cells are bona fide T regulatory cells with strong immunomodulatory properties that are not only able to prevent disease onset, but also to interfere with an ongoing inflammatory immune response.  相似文献   
125.
Understanding how genetic alterations affect gene products at the molecular level represents a first step in the elucidation of the complex relationships between genotypic and phenotypic variations, and is thus a major challenge in the postgenomic era. Here, we present SM2PH‐db ( http://decrypthon.igbmc.fr/sm2ph ), a new database designed to investigate structural and functional impacts of missense mutations and their phenotypic effects in the context of human genetic diseases. A wealth of up‐to‐date interconnected information is provided for each of the 2,249 disease‐related entry proteins (August 2009), including data retrieved from biological databases and data generated from a Sequence–Structure–Evolution Inference in Systems‐based approach, such as multiple alignments, three‐dimensional structural models, and multidimensional (physicochemical, functional, structural, and evolutionary) characterizations of mutations. SM2PH‐db provides a robust infrastructure associated with interactive analysis tools supporting in‐depth study and interpretation of the molecular consequences of mutations, with the more long‐term goal of elucidating the chain of events leading from a molecular defect to its pathology. The entire content of SM2PH‐db is regularly and automatically updated thanks to a computational grid data federation facilities provided in the context of the Decrypthon program. Hum Mutat 31:127–135, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
126.

Background

Abnormal NF-??B2 activation has been implicated in the pathogenesis of multiple myeloma, a cancer of plasma cells. However, a causal role for aberrant NF-??B2 signaling in the development of plasma cell tumors has not been established. Also unclear is the molecular mechanism that drives the tumorigenic process. We investigated these questions by using a transgenic mouse model with lymphocyte-targeted expression of p80HT, a lymphoma-associated NF-??B2 mutant, and human multiple myeloma cell lines.

Methods

We conducted a detailed histopathological characterization of lymphomas developed in p80HT transgenic mice and microarray gene expression profiling of p80HT B cells with the goal of identifying genes that drive plasma cell tumor development. We further verified the significance of our findings in human multiple myeloma cell lines.

Results

Approximately 40% of p80HT mice showed elevated levels of monoclonal immunoglobulin (M-protein) in the serum and developed plasma cell tumors. Some of these mice displayed key features of human multiple myeloma with accumulation of plasma cells in the bone marrow, osteolytic bone lesions and/or diffuse osteoporosis. Gene expression profiling of B cells from M-protein-positive p80HT mice revealed aberrant expression of genes known to be important in the pathogenesis of multiple myeloma, including cyclin D1, cyclin D2, Blimp1, survivin, IL-10 and IL-15. In vitro assays demonstrated a critical role of Stat3, a key downstream component of IL-10 signaling, in the survival of human multiple myeloma cells.

Conclusions

These findings provide a mouse model for human multiple myeloma with aberrant NF-??B2 activation and suggest a molecular mechanism for NF-??B2 signaling in the pathogenesis of plasma cell tumors by coordinated regulation of plasma cell generation, proliferation and survival.  相似文献   
127.
BACKGROUND: Carotenoids are thought to have anti-cancer properties, but findings from population-based research have been inconsistent. OBJECTIVE: We aimed to conduct a systematic review of the associations between carotenoids and lung cancer. DESIGN: We searched electronic databases for articles published through September 2007. Six randomized clinical trials examining the efficacy of beta-carotene supplements and 25 prospective observational studies assessing the associations between carotenoids and lung cancer were analyzed by using random-effects meta-analysis. RESULTS: The pooled relative risk (RR) for the studies comparing beta-carotene supplements with placebo was 1.10 (95% confidence limits: 0.89, 1.36; P = 0.39). Among the observational studies that adjusted for smoking, the pooled RRs comparing highest and lowest categories of total carotenoid intake and of total carotenoid serum concentrations were 0.79 (0.71, 0.87; P < 0.001) and 0.70 (0.44, 1.11; P = 0.14), respectively. For beta-carotene, highest compared with lowest pooled RRs were 0.92 (0.83, 1.01; P = 0.09) for dietary intake and 0.84 (0.66, 1.07; P = 0.15) for serum concentrations. For other carotenoids, the RRs comparing highest and lowest categories of intake ranged from 0.80 for beta-cryptoxanthin to 0.89 for alpha-carotene and lutein-zeaxanthin; for serum concentrations, the RRs ranged from 0.71 for lycopene to 0.95 for lutein-zeaxanthin. CONCLUSIONS: beta-Carotene supplementation is not associated with a decrease in the risk of developing lung cancer. Findings from prospective cohort studies suggest inverse associations between carotenoids and lung cancer; however, the decreases in risk are generally small and not statistically significant. These inverse associations may be the result of carotenoid measurements' function as a marker of a healthier lifestyle (higher fruit and vegetable consumption) or of residual confounding by smoking.  相似文献   
128.

Objective

To determine predictors of repeat abortion in 3 provinces in Vietnam.

Methods

In a cross-sectional study between August and December 2011, women who underwent abortion were interviewed after the procedure in 62 public health facilities in Hanoi, Khanh Hoa, and Ho Chi Minh City (HCMC). Information on sociodemographic factors, contraceptive and reproductive history and intentions, and opinions and experience of abortion services was collected. The primary outcome was repeat (≥ 2) abortions.

Results

Overall, 1224 women were interviewed: 534 from Hanoi, 163 from Khanh Hoa, and 527 from HCMC. The mean age and parity of the respondents were 29 years and 1.8, respectively, and 79.6% were married. Approximately half of the respondents were not using contraception before pregnancy. The prevalence of repeat abortion was 31.7%. In multivariate models, significant predictors of repeat abortion included living in Hanoi, higher parity, age 35 years or older, and having 2 or more daughters (versus 1) or no sons (versus 1) after controlling for parity (all P < 0.05).

Conclusion

Repeat abortion remains high in Vietnam, fueled partly by inadequate contraceptive use. Son preference seems to be an important predictor of repeat abortion. Strengthening post-abortion contraceptive counseling and promoting long-acting contraceptive methods are essential to reduce repeat abortion.  相似文献   
129.

Objective

To investigate the attributes of service users associated with uptake of medical abortion (MA) versus manual vacuum aspiration (MVA) at public health facilities in Vietnam.

Methods

Structured exit interviews were conducted among women who underwent termination at 62 public health facilities in Hanoi, Khanh Hoa, and Ho Chi Minh City (HCMC) between August and December 2011. Data on sociodemographic, abortion-related, and service-related factors were compared between women who underwent MVA versus MA.

Results

Overall, 1233 women completed the study survey: 541 (43.9%) from Hanoi; 163 (13.2%) from Khanh Hoa; and 529 (42.9%) from HCMC. Almost one-quarter of women (23.1%) had chosen MA. After controlling for sociodemographic factors, women living in Khanh Hoa (odds ratio [OR], 13.4; 95% confidence interval [CI], 5.3–33.8) and HCMC (OR, 5.8; 95% CI, 2.1–15.9) were more likely to have undergone MA than women in Hanoi. Older women were less likely to have undergone MA (P < 0.05), and those who had previously heard of MA were twice as likely to have undergone MA (P = 0.020).

Conclusion

Uptake of MA was lower than that of MVA and varied by province. Women in Vietnam will make their own judgment about which method to choose if they have prior knowledge of both.  相似文献   
130.
Adding amylase to fortified blended foods can improve energy density, and increase child's energy and nutrient intake. The efficacy of this strategy is unknown for the World Food Programme's Super Cereal Plus (SC+) and Super Cereal (SC) blends. The primary goal of this study was to investigate the increased energy intake from amylase‐containing SC+ and SC compared to control porridges in Burkinabe children. Secondly, energy intake from amylase‐containing porridges compared to CERELAC®, Vitazom, and eeZeeBAR? was studied. Thirdly, caregivers' (n = 100) porridge acceptability was investigated. The design was a randomized double‐blind controlled cross‐over trial studying the effect of amylase addition to SC+ and SC flours on porridge energy and nutrient intake in healthy Burkinabe children aged 12–23 (n = 80) and 24–35 months (n = 40). Amylase added to porridges increased energy density from 0.68 to 1.16 kcal/g for SC+ and from 0.66 to 1.03 kcal/g for SC porridges. Among children aged 12–23 months, mean energy intake from all porridges with amylase (135–164 kcal/meal) was significantly higher compared to control SC+ porridges (84–98 kcal/meal; model‐based average). Among children aged 24–35 months, mean energy intakes were also significantly higher from all porridges with amylase added (245–288 kcal/meal) compared to control SC porridges (175–183 kcal/meal). Acceptability of the porridges among caregivers was rated neutral to good, both for amylase‐added and non‐amylase‐containing porridges. These findings suggest that, among 12–35‐month‐old, adding amylase to fortified blended foods significantly increased energy and consequently nutrient intake per meal by 67% for SC+ and 47% for SC. Moreover, amylase‐containing porridges were well accepted by the caregivers.  相似文献   
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