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31.
To determine the late gestational development of copper-zinc (CnZn) and manganese (Mn) superoxide dismutases (SOD) in human lung, immunohistochemical localization was performed for each SOD. The lung samples were taken from five aborted fetuses, four fetuses in which intrauterine death occurred, one full-term neonate, two premature infants with hyaline membrane disease and one premature infant with bronchopulmonary dysplasia (BPD). Morphometry was performed, and the percent area of positive staining was computed. The bronchial epithelium was intensely stained from the early stages of gestation (i.e. 17 weeks), while the staining intensity for both CuZnSOD and MnSOD in the peripheral airways increased gradually during lung development. The mean percent area of the staining for CuZnSOD and MnSOD from 16 to 38 weeks was increased 30-fold and 8-fold, respectively, and further increases were observed postnatally. CuZnSOD staining was markedly decreased in lungs with respiratory disorders. However, proliferating type II pneumocytes were intensely stained for MnSOD in the BPD lungs, making the staining area 3-fold larger than that in the control lungs. These results clearly depict age-related increases in staining for both CuZnSOD and MnSOD and an alteration in SOD distribution associated with neonatal respiratory disorders.  相似文献   
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Chromosome 2 (2p16) abnormalities in Carney complex tumours   总被引:6,自引:0,他引:6       下载免费PDF全文
Carney complex (CNC) is an autosomal dominant multiple endocrine neoplasia and lentiginosis syndrome characterised by spotty skin pigmentation, cardiac, skin, and breast myxomas, and a variety of endocrine and other tumours. The disease is genetically heterogeneous; two loci have been mapped to chromosomes 17q22–24 (the CNC1 locus) and 2p16 (CNC2). Mutations in the PRKAR1A tumour suppressor gene were recently found in CNC1 mapping kindreds, while the CNC2 and perhaps other genes remain unidentified. Analysis of tumour chromosome rearrangements is a useful tool for uncovering genes with a role in tumorigenesis and/or tumour progression. CGH analysis showed a low level 2p amplification recurrently in four of eight CNC tumours; one tumour showed specific amplification of the 2p16-p23 region only. To define more precisely the 2p amplicon in these and other tumours, we completed the genomic mapping of the CNC2 region, and analysed 46 tumour samples from CNC patients with and without PRKAR1A mutations by fluorescence in situ hybridisation (FISH) using bacterial artificial chromosomes (BACs). Consistent cytogenetic changes of the region were detected in 40 (87%) of the samples analysed. Twenty-four samples (60%) showed amplification of the region represented as homogeneously stained regions (HSRs). The size of the amplicon varied from case to case, and frequently from cell to cell in the same tumour. Three tumours (8%) showed both amplification and deletion of the region in their cells. Thirteen tumours (32%) showed deletions only. These molecular cytogenetic changes included the region that is covered by BACs 400-P-14 and 514-O-11 and, in the genetic map, corresponds to an area flanked by polymorphic markers D2S2251 and D2S2292; other BACs on the centromeric and telomeric end of this region were included in varying degrees. We conclude that cytogenetic changes of the 2p16 chromosomal region that harbours the CNC2 locus are frequently observed in tumours from CNC patients, including those with germline, inactivating PRKAR1A mutations. These changes are mostly amplifications of the 2p16 region, that overlap with a previously identified amplicon in sporadic thyroid cancer, and an area often deleted in sporadic adrenal tumours. Both thyroid and adrenal tumours constitute part of CNC indicating that the responsible gene(s) in this area may indeed be involved in both inherited and sporadic endocrine tumour pathogenesis and/or progression.  相似文献   
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Remarkable progress over the last decade has put Bangladesh on track for Millennium Development Goal (MDG) 4 for child survival and achieved a 40% decline in maternal mortality. However, since neonatal deaths make up 57% of under-five mortality in the country, increased scale up and equity in programmes for neonatal survival are critical to sustain progress. We examined change for newborn survival from 2000 to 2010 considering mortality, coverage and funding indicators, as well as contextual factors. The national neonatal mortality rate has undergone an annual decline of 4.0% since 2000, reflecting greater progress than both the regional and global averages, but the mortality reduction for children 1-59 months was double this rate, at 8.6%. Examining policy and programme change, and national and donor funding for health, we identified various factors which contributed to an environment favourable to newborn survival. Locally-generated evidence combined with re-packaged global evidence, notably The Lancet Neonatal Series, has played a role, although pathways between research and policies and programme change are often complex. Several high-profile champions have had major influence. Attention for community initiatives and considerable donor funding also appear to have contributed. There have been some increases in coverage of key interventions, such as skilled attendance at birth and postnatal care, however these are low and reach less than one-third of families. Major reductions in total fertility, some change in gross national income and other contextual factors are likely to also have had an influence in mortality reduction. However, other factors such as socio-economic and geographic inequalities, frequent changes in government and pluralistic implementation structures have provided challenges. As coverage of health services increases, a notable gap remains in quality of facility-based care. Future gains for newborn survival in Bangladesh rest upon increased implementation at scale and greater consistency in content and quality of programmes and services.  相似文献   
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Trillium govanianum Wall. (Melanthiaceae alt. Trilliaceae), commonly known as ‘nag chhatri’ or ‘teen patra’, is a native species of the Himalayas. It is used in various traditional medicines containing both steroids and sex hormones. In folk medicine, the rhizomes of T. govanianum are used to treat boils, dysentery, inflammation, menstrual and sexual disorders, as an antiseptic and in wound healing. With the only exception of the recent report on the isolation of a new steroidal saponin, govanoside A, together with three known steroidal compounds with antifungal property from this plant, there has been no systematic pharmacological and phytochemical work performed on T. govanianum. This paper reports, for the first time, on the cytotoxicity of the methanol extract of the roots of T. govanianum and its solid‐phase extraction (SPE) fractions against four human carcinoma cell lines: breast (MCF7), liver (HEPG2), lung (A549) and urinary bladder (EJ138), using the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazoliumbromide cytotoxicity assay and liquid chromatography and electrospray ionization quadrupole time‐of‐flight mass spectrometry analysis of the SPE fractions. The methanol extract and all SPE fractions exhibited considerable levels of cytotoxicity against all cell lines, with the IC50 values ranging between 5 and 16 µg/mL. Like other Trillium species, presence of saponins and sapogenins in the SPE fractions was evident in the liquid chromatography mass spectrometry data. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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