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71.
Fish and other seafood may contain organic mercury but also beneficial nutrients such as n-3 polyunsaturated fatty acids. We endeavored to study whether maternal fish consumption during pregnancy harms or benefits fetal brain development. We examined associations of maternal fish intake during pregnancy and maternal hair mercury at delivery with infant cognition among 135 mother-infant pairs in Project Viva, a prospective U.S. pregnancy and child cohort study. We assessed infant cognition by the percent novelty preference on visual recognition memory (VRM) testing at 6 months of age. Mothers consumed an average of 1.2 fish servings per week during the second trimester. Mean maternal hair mercury was 0.55 ppm, with 10% of samples > 1.2 ppm. Mean VRM score was 59.8 (range, 10.9-92.5). After adjusting for participant characteristics using linear regression, higher fish intake was associated with higher infant cognition. This association strengthened after adjustment for hair mercury level: For each additional weekly fish serving, offspring VRM score was 4.0 points higher [95% confidence interval (CI), 1.3 to 6.7]. However, an increase of 1 ppm in mercury was associated with a decrement in VRM score of 7.5 (95% CI, -13.7 to -1.2) points. VRM scores were highest among infants of women who consumed > 2 weekly fish servings but had mercury levels 相似文献   
72.
Background: Very low birth weight (VLBW) infants miss out on the period of greatest mineral accretion that occurs during the last trimester of pregnancy and are at higher risk of enamel defects. No studies have well described the relationship between neonatal nutrition and dental outcomes in preterm, VLBW infants. The objective of this study was to assess the differences in nutrition biomarkers, feeding intake, and comorbidities among VLBW infants with and without enamel defects. Methods: A retrospective chart review of VLBW infants recruited for an ongoing longitudinal dental study between 2007 and 2010 was done. Participants were classified as cases and controls according to the presence/absence of developmental defects of enamel at 8 and/or 18–20 and/or 36 months. Demographics and medical and nutrition data were abstracted from 76 subjects' medical charts. Results: Of the 76 VLBW subjects, 62% had enamel defects (hypoplasia and/or opacity). The only significant variable in the logistic regression analysis was that infants with a 1‐mg/dL increase in serum phosphorus levels had a 68% reduction in the odds of having enamel hypoplasia (odds ratio, 0.322; P = .024). Conclusion: Neonatal lower serum phosphorus levels are significantly associated with enamel hypoplasia in VLBW infants younger than 3 years.  相似文献   
73.
Population-based estimates of human immunodeficiency virus (HIV) prevalence and risk behaviors among men who have sex with men (MSM) are valuable for HIV prevention planning but not widely available, especially at the local level. We combined two population-based data sources to estimate prevalence of diagnosed HIV infection, HIV-associated risk-behaviors, and HIV testing patterns among sexually active MSM in New York City (NYC). HIV/AIDS surveillance data were used to determine the number of living males reporting a history of sex with men who had been diagnosed in NYC with HIV infection through 2002 (23% of HIV-infected males did not have HIV transmission risk information available). Sexual behavior data from a cross-sectional telephone survey were used to estimate the number of sexually active MSM in NYC in 2002. Prevalence of diagnosed HIV infection was estimated using the ratio of HIV-infected MSM to sexually active MSM. The estimated base prevalence of diagnosed HIV infection was 8.4% overall (95% confidence interval [CI] = 7.5–9.6). Diagnosed HIV prevalence was highest among MSM who were non-Hispanic black (12.6%, 95% CI = 9.8–17.6), aged 35–44 (12.6%, 95% CI = 10.4–15.9), or 45–54 years (13.1%, 95% CI = 10.2–18.3), and residents of Manhattan (17.7%, 95% CI = 14.5–22.8). Overall, 37% (95% CI = 32–43%) of MSM reported using a condom at last sex, and 34% (95% CI = 28–39%) reported being tested for HIV in the past year. Estimates derived through sensitivity analyses (assigning a range of HIV-infected males with no reported risk information as MSM) yielded higher diagnosed HIV prevalence estimates (11.0–13.2%). Accounting for additional undiagnosed HIV-infected MSM yielded even higher prevalence estimates. The high prevalence of diagnosed HIV among sexually active MSM in NYC is likely due to a combination of high incidence over the course of the epidemic and prolonged survival in the era of highly active antiretroviral therapy. Despite high HIV prevalence in this population, condom use and HIV testing are low. Combining complementary population-based data sources can provide critical HIV-related information to guide prevention efforts. Individual counseling and education interventions should focus on increasing condom use and encouraging safer sex practices among all sexually active MSM, particularly those groups with low levels of condom use and multiple sex partners At the time this work was conducted, Manning and Marx were with the Epidemic Intelligence Service, Office of Workforce and Career Development, Centers for Disease Control and Prevention, Atlanta, GA, USA; Thorpe, Ramaswamy, Hajat, Marx, Karpati, Mostashari, and Pfeiffer are with the New York City Department of Health and Mental Hygiene, New York, NY, USA; Nash is with the Department of Epidemiology and International Center for AIDS Care and Treatment Programs, Columbia Mailman School of Public Health, New York, NY, USA; Manning is with the Massachusetts Department of Public Health, Bureau of Family and Community Health, Boston, MA, USA.  相似文献   
74.

Background:

Globally, Telephone help-lines have proved their utility in several crisis situations. They were introduced in India for helping persons in need of counseling or emergency care such as victims of suicide, cardiac arrests, etc. The utility of such help-lines in HIV/AIDS has not been established .Hence this study done in ASHA Foundation, Bangalore.

Objectives:

To determine the characteristics of persons who access the HIV/AIDS helpline. To determine the reasons for calling the helpline. To identify the gaps in the provision of this service.

Materials and Methods:

Details on all calls received on ASHA Foundation''s HIV/AIDS help line during the period January 2007 to December 2008, were entered on MS excel worksheet and analyzed using the SPSS software.

Results:

Majority of callers are male, are in the age group of 20-39 years and educated. The most common reasons for calling the helpline were for HIV testing, information about HIV/AIDS, care and support services and referrals to other services not linked to HIV/AIDS. Reasons for calling were linked to risk ( HIV testing, condom use etc) in younger persons, and to avail of care and support services in the older age-group.

Conclusions:

The main users of the HIV/AIDS helpline are urban ,young, educated males.  相似文献   
75.
Cancer is a Preventable Disease that Requires Major Lifestyle Changes   总被引:3,自引:0,他引:3  
This year, more than 1 million Americans and more than 10 million people worldwide are expected to be diagnosed with cancer, a disease commonly believed to be preventable. Only 5-10% of all cancer cases can be attributed to genetic defects, whereas the remaining 90-95% have their roots in the environment and lifestyle. The lifestyle factors include cigarette smoking, diet (fried foods, red meat), alcohol, sun exposure, environmental pollutants, infections, stress, obesity, and physical inactivity. The evidence indicates that of all cancer-related deaths, almost 25-30% are due to tobacco, as many as 30-35% are linked to diet, about 15-20% are due to infections, and the remaining percentage are due to other factors like radiation, stress, physical activity, environmental pollutants etc. Therefore, cancer prevention requires smoking cessation, increased ingestion of fruits and vegetables, moderate use of alcohol, caloric restriction, exercise, avoidance of direct exposure to sunlight, minimal meat consumption, use of whole grains, use of vaccinations, and regular check-ups. In this review, we present evidence that inflammation is the link between the agents/factors that cause cancer and the agents that prevent it. In addition, we provide evidence that cancer is a preventable disease that requires major lifestyle changes.  相似文献   
76.
2,3,7,8-Tetrachlorodibenzo- p-dioxin (TCDD) is one of the most potent environmental contaminants, which has been shown to induce oxidative stress in testis and epididymal sperm of rats. However, the nature and mechanism of action of TCDD on the epididymis is not clear. The aim of the present study was to investigate whether induction of oxidative stress in epididymal sperm was direct effect of TCDD on epididymis. In the present studies, TCDD (0.1, 1.0 and 10 micro g/kg body weight per day) was administered orally to rats for 4 days. Twenty-four hours after the last treatment the animals were killed using anesthetic ether. Both epididymides were dissected out and epididymal sperm were collected by cutting the epididymides into small pieces in Ham's F-12 medium at 35 degrees C. The epididymal sperm and caput, corpus and cauda epididymides were homogenized and used for biochemical studies. Epididymal sperm counts did not decrease in the rats treated with TCDD. Administration of TCDD increased the production of reactive oxygen species such as hydrogen peroxide while the activities of antioxidant enzymes superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase were found to be decreased in the epididymal sperm as well as in cauda epididymides. Lipid peroxidation also increased in the epididymal sperm and in the various regions of the epididymides after exposure to TCDD. The results indicated that TCDD induces oxidative stress in the epididymis and epididymal sperm by decreasing the antioxidant enzymes through induction of reactive oxygen species. Thus, the adverse effects of TCDD on the epididymal sperm were due to direct effect of TCDD on epididymis.  相似文献   
77.
Expression of CD44 in glioma cells was previously correlated with tumor grade and is considered a stem cell marker. CD44 stabilizes the cystine–glutamate transporter (xCT) and inhibits apoptosis in cancer stem cells (CSCs). Recently it was found that Sulfasalazine (SSZ), an anti-inflammatory drug, acts as an inhibitor of xCT and therefore has potential as a targeted therapy for CSCs. In this study, we tested an efficacy of SSZ against glioma stem cell model developed in rats. As poor penetration of blood–brain barrier resulted in insufficient efficacy of systemic SSZ treatment, SSZ was delivered locally with convection-enhanced delivery (CED). In vitro, expression of CD44 in glioma cells and efficacy of SSZ against glioma cells and glioma stem cells were confirmed. SSZ demonstrated anti-proliferative activity in a dose dependent manner against these cells. This activity was partially reversible with the addition of antioxidant, N-acetyl-l-cysteine, to the medium. In vivo, CED successfully delivered SSZ into the rat brain parenchyma. When delivered at 5 mM concentration, which was the highest possible concentration when SSZ was dissolved in water, CED of SSZ resulted in almost no tissue damage. Against highly malignant bRiTs-G3 brain tumor xenografted rat model; the glioma stem cell model, CED of SSZ at 5 mM concentration induced apoptosis and prolonged survival. Consequently, CED of SSZ induced glioma stem cell death without evidence of tissue damage to normal brain parenchyma. This strategy may be a promising targeted treatment against glioma stem cells.  相似文献   
78.
The genetic alterations frequently involved in glial malignancies are in the tumor suppressor genes, Rb and p53. An altered Rb expression or p53 overexpression is thought to indicate defective tumor suppression and subsequently more aggressive tumors. Therefore, to assess the alterations in the conjoint expression of Rb and p53 proteins in formalin fixed paraffin embedded sections, 64 astrocytic tumors were studied (16 astrocytomas,7 gemistocytic astrocytomas, 19 anaplastic astrocytomas and 22 glioblastomas) using the avidin biotin immunoperoxidase technique. Fifty two cases (81.25%) were found to be positive for p53 protein. Seventeen of these showed aberrant heterogenous staining for pRb, of which 7 were glioblastomas. Only one case of astrocytoma showed aberrant expression of both p53 and Rb. Thus, of the 64 tumors, simultaneous aberrant expression of both p53 and Rb was seen in 21.9% of cases. This was more commonly observed among glioblastoma cases (7/22). No statistical difference was found between the survival rate of heterogenous pRb and p53 positivity in different grades of tumors. In glioblastomas, the survival rate appeared to be less in patients expressing heterogenous pRb, but this was not statistically significant. These results lead us to suspect that p53 and pRb pathways are inactivated, either through mutation or as part of the neoplastic process in astrocytic tumors.  相似文献   
79.
Arsenic is a well-established human carcinogen; however molecular mechanisms to arsenic-induced carcinogenesis are complex and elusive. The present study identifies a potential biomarker of arsenic exposure, and redefines arsenic-induced signaling in stimulation of cell proliferation. The effect of arsenic exposure on gene expression was evaluated in PBMC of arsenic-exposed individuals selected from a severely affected district of West Bengal, India. A novel, un-documented biomarker of arsenic exposure, CyclinA was identified by microarray analysis from the study. Non-transformed cell lines HaCat and Int407 when exposed to clinically achievable arsenic concentration showed significant increase of CyclinA substantiating the clinical data. An associated increase in S phase population of cells in cell cycle, indicative of enhanced proliferation was also noticed. On further investigation of the pathway to arsenic-induced proliferation, we observed that arsenic resulted: ROS generation; activated Erk signaling; stimulated AP-1 activity, including immediate early genes, c-Jun and c-Fos. N-Acetyl-l-cysteine, a ROS quencher, blocked the arsenic-induced effects. Our study underlines a previously undefined mechanism by which arsenic imparts its toxicity and results in uncontrolled cell proliferation.  相似文献   
80.
An in vivo bromodeoxyuridine (BrdU) labeling index (LI) was estimated in 43 cases of astrocytic tumors and mixed gliomas by one hour intra-operative intravenous infusion at a dose of 200 mg/m2 and correlated with (a) histological grading using a computer aided malignancy classifier TESTAST-268; and (b) histological typing using WHO classification. The lowest BrdU LI was seen in pilocytic and gemistocytic astrocytomas followed by astrocytomas, anaplastic astrocytomas and glioblastoma multiforme in that order. Mixed oligoastrocytomas followed the pattern of their astrocytic counterparts. Tumors of similar histological type showed different BrdU LI values especially amongst astrocytomas and glioblastomas. A statistically significant difference in the BrdU LI was also noted between the higher TESTAST grades of astrocytomas (T III and IV) versus the lower TESTAST grades (T II). Unlike earlier reports in literature, in the present study the category of BrdU LI of <1 contained no case of anaplastic astrocytoma or glioblastoma multiforme (TESTAST grades III and IV). Likewise, the category of BrdU LI >5 contained only anaplastic astrocytoma and glioblastoma multiforme (TESTAST grades III and IV). Maximum spread of cases was seen in the BrdU LI category of 1-5, not only in terms of histological types but also TESTAST grades. Thus there appeared to be a positive trend of increasing BrdU LI values both with histological types and increasing TESTAST grades. Further, an interesting observation was that by using a combination of TESTAST grades and BrdU LI, the histologically homogenous glioblastoma group could be further subdivided into 4 categories which showed a trend towards prognostic correlation. Thus, this study though preliminary with number of cases being small in some groups, highlights the possible usefulness of combined histological typing, TESTAST grading and in vivo BrdU LI for prognostication of gliomas especially glioblastoma multiforme.  相似文献   
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