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Neonatal hypoxic-ischemic brain injury remains a significant cause of morbidity and mortality and lacks effective therapies for prevention and treatment. Recently, interest in the biology of polyphenol compounds has led to the discovery that dietary supplementation with foods rich in polyphenols (e.g. blueberries, green tea extract) provides neuroprotection in adult animal models of ischemia and Alzheimer's disease. We sought to determine whether protection of the neonatal brain against a hypoxic-ischemic insult could be attained through supplementation of the maternal diet with pomegranate juice, notable for its high polyphenol content. Mouse dams were provided ad libitum access to drinking water with pomegranate juice, at one of three doses, as well as plain water, sugar water, and vitamin C water controls during the last third of pregnancy and throughout the duration of litter suckling. At postnatal day 7, pups underwent unilateral carotid ligation followed by exposure to 8% oxygen for 45 min. Brain injury was assessed histologically after 1 wk (percentage of tissue area loss) and biochemically after 24 h (caspase-3 activity). Dietary supplementation with pomegranate juice resulted in markedly decreased brain tissue loss (>60%) in all three brain regions assessed, with the highest pomegranate juice dose having greatest significance (p < or = 0.0001). Pomegranate juice also diminished caspase-3 activation by 84% in the hippocampus and 64% in the cortex. Ellagic acid, a polyphenolic component in pomegranate juice, was detected in plasma from treated but not control pups. These results demonstrate that maternal dietary supplementation with pomegranate juice is neuroprotective for the neonatal brain.  相似文献   
94.
Vulvar clear cells of Toker: precursors of extramammary Paget's disease   总被引:3,自引:0,他引:3  
Clear cells of Toker are intraepithelial cells with clear to pale staining cytoplasm and bland cytologic features found with H&E staining in approximately 10% of normal nipples. Toker cells have been hypothesized as a precursor of extramammary Paget's disease (EMPD), although Toker cells have not been identified as a normal component of genital skin. Using immunohistochemistry, we studied 11 vulvectomies for the presence of Toker cells in association with mammary-like glands of the vulva (MLG). A retrospective study of 11 vulvectomies was performed using routine hematoxylin and eosin staining, as well as immunohistochemical staining for cytokeratin 7 (CK7). Control sections of skin not involving the milk line from age-matched patients were also examined. Four of eleven vulvectomies (36%) demonstrated Toker cells with CK7 staining. Toker cells were associated with the openings of the ducts of mammary-like glands of the vulva. Toker cells were not seen in control tissues. Toker cells occur as a normal constituent of genital skin in association with mammary-like glands of the vulva. Previous morphologic, immunohistochemical, and ultrastructural evidence have pointed to Toker cells as a precursor of EMPD. The demonstration of Toker cells in genital skin strengthens the evidence of their role in the development of EMPD.  相似文献   
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Recently, the findings of 1 mortality follow-up study have raised concern regarding the risk of brain cancer among women with cosmetic breast implants. In this review, the authors examine the results of 4 existing large-scale incidence follow-up studies comprising more than 10,000 women with cosmetic implants followed for as long as 29 years. Overall, there were 12 observed incident cases of brain cancer compared with 9.6 cases expected, yielding a nonstatistically significant summary standardized incidence ratio of 1.25 (95% confidence interval, 0.7-2.2). Based on the confidence interval alone, this result rules out the standardized mortality ratio of 2.45 reported in the 1 positive mortality study. Overall, the epidemiologic evidence does not support an association between breast implants and brain cancer incidence.  相似文献   
97.
Structural changes of proteins during adsorption to biomaterials affect the presentation of molecular binding sites and, ultimately, biomaterial performance. We have applied fluorescence resonance energy transfer (FRET) spectroscopy to study structural changes of the cell adhesion protein, fibronectin (Fn), following adsorption to model hydrophilic and hydrophobic surfaces. Fn was labeled with donor and acceptor fluorophores using two labeling schemes and intramolecular energy transfer was calibrated against measured structural changes of Fn in denaturing solutions. FRET was then applied to measure Fn's structure on surfaces. Based on FRET, Fn underwent greater extension of its dimer arms on hydrophilic glass than on hydrophobic fluoroalklysilane-derivatized glass (fluorosilane), and this extension was insensitive to molecular packing over a range of adsorption concentrations. Fn's conformation on glass better promoted cell attachment than on fluorosilane; the roles of both global structural changes (movements of modules) and local structural changes (disruption of secondary structure) on Fn's cell integrin binding activity are discussed. Based on previous FRET work, we compare Fn's conformations on these surfaces with its conformations in fibroblast culture. FRET is unique in allowing direct comparison of protein structure between biomaterial surfaces and cell culture.  相似文献   
98.
Information on circumcision is available on the Internet, which is available for parents to review. The purpose of this study is to sample and summarize the Internet's informational content on circumcision. One hundred web sites were identified using the Google search engine on February 15, 2003. The informational content of each site was reviewed and tabulated. Seventy-three of the 100 web sites were appropriate for review. Ten agreed with recommending circumcision, 4 agreed under limited circumstances, 37 recommended against circumcision, and 4 recommended against circumcision under limited circumstances. Eighteen did not take a stance for or against. Thirteen agreed that circumcision reduces the risk of urinary tract infection, and 16 disagreed with this. Fifteen agreed that circumcision reduces the risk of penile cancer and 14 disagreed with this. Fifty-one percent of web sites surveyed were against circumcision, 14% of the web sites surveyed recommended circumcision, and 25% of surveyed web sites had no opinion.  相似文献   
99.
Cellular cardiomyoplasty is an expanding field of research that involves numerous types of immature cells administered via several modes of delivery. The purpose of this review is to investigate the benefits of different types of cells used in stem cell research as well as the most efficient mode of delivery. The authors also present data showing that stem cells isolated from bone marrow are present at both 2 weeks and 3 months after engraftment in a myocardial infarction. These cells express muscle markers at both time points, which suggests that they have begun to differentiate into cardiomyocytes. Several questions must be answered, however, before stem cells can be used routinely in the clinic. Once these questions have been addressed, the use of stem cells in clinical practice can be realized.  相似文献   
100.
The current study investigated the connection between religion and mental health of 131 rural, low-income mothers. Two dimensions of religion, beliefs and faith community involvement, were included and depression was assessed by the CES-D. The sample consisted of mothers who participated in Wave 2 of a multi-state research project. As hypothesized, both religious beliefs and faith community involvement were negatively related to depressive symptoms indicating that mothers with stronger religious beliefs and more involvement in religious activities may experience less depressive symptoms. The results of the current study confirm previous work and support a multifaceted view of religion.  相似文献   
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