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Zinc protoporphyrin IX (ZnPP), an endogenous heme analogue that inhibits heme oxygenase (HO) activity, represses tumor growth. It can also translocate into the nucleus and up-regulate heme oxygenase 1 (HMOX1) gene expression. Here, we demonstrate that tumor cell proliferation was inhibited by ZnPP, whereas tin protoporphyrin (SnPP), another equally potent HO-1 inhibitor, had no effect. Microarray analysis on 128 tumorigenesis related genes showed that ZnPP suppressed genes involved in cell proliferation and angiogenesis. Among these genes, CYCLIN D1 (CCND1) was specifically inhibited as were its mRNA and protein levels. Additionally, ZnPP inhibited CCND1 promoter activity through an Sp1 and Egr1 overlapping binding site (S/E). We confirmed that ZnPP modulated the S/E site, at least partially by associating with Sp1 and Egr1 proteins rather than direct binding to DNA targets. Furthermore, administration of ZnPP significantly inhibited cyclin D1 expression and progression of a B-cell leukemia/lymphoma 1 tumor in mice by preferentially targeting tumor cells. These observations show HO independent effects of ZnPP on cyclin D1 expression and tumorigenesis.  相似文献   
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Background  

A large number of genetic variations have been identified in rice. Such variations must in many cases control phenotypic differences in abiotic stress tolerance and other traits. A single feature polymorphism (SFP) is an oligonucleotide array-based polymorphism which can be used for identification of SNPs or insertion/deletions (INDELs) for high throughput genotyping and high density mapping. Here we applied SFP markers to a lingering question about the source of salt tolerance in a particular rice recombinant inbred line (RIL) derived from a salt tolerant and salt sensitive parent.  相似文献   
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Introduction

Gastro-oesophageal reflux disease (GORD) is a common problem in the Western countries, and the interest in the minimal access surgical approaches to treat GORD is increasing. In this study, we would like to discuss the presentations and management of complications we encountered after Laparoscopic Nissen's fundoplication in our District General NHS Hospital. The aim is to recognise these complications at the earliest stage for effective management to minimise the morbidity and mortality.

Methods

301 patients underwent laparoscopic treatment for GORD by a single consultant surgeon in our NHS Trust from September 1999. The data was prospectively collected and entered into a database. The data was retrospectively analysed for presentations for complications and their management.

Results

Surgery was completed laparoscopically in all patients, except in five, where the operation was technically difficult due to pre-existing conditions. The complications we encountered during surgery and follow-up period were major intra-operative bleeding (n = 1, 0.33%), severe post-operative nausea and vomiting (n = 1, 0.33%), wound infection (n = 3, 1%), port-site herniation (n = 1, 0.33%), wrap-migration (n = 2, 0.66%), wrap-ischaemia (n = 1, 0.33%), recurrent regurgitation (n = 4, 1.32%), recurrent heartburn (n = 29, 9.63%), tension pneumothorax (n = 2, 0.66%), surgical emphysema (n = 8, 2.66%), and port-site pain (n = 4, 1.33%).

Conclusion

Minimal access approach to treat GORD has presented with some specific and unique complications. It is important to recognise these complications at the earliest possible stage as some of these patients may present in an acute setting requiring emergency surgery. All members of the department, and not just the members of the specialised team, should be aware about these complications to minimise the morbidity and mortality.  相似文献   
76.

Background

This is a predictive validity study examining the extent to which developmental vulnerability at kindergarten entry (as measured by the Early Development Instrument, EDI) is associated with children''s basic skills in 4th grade (as measured by the Foundation Skills Assessment, FSA).

Methodology/Principal Findings

Relative risk analysis was performed on a large database linking individual-level EDI ratings to the scores the same children obtained on a provincial assessment of academic skills (FSA – Foundation Skills Assessment) four years later. We found that early vulnerability in kindergarten is associated with the basic skills that underlie populations of children''s academic achievement in reading, writing and math, indicating that the Early Development Instrument permits to predict achievement-related skills four years in advance.

Conclusions/Significance

The EDI can be used to predict children''s educational trends at the population level and can help select early prevention and intervention programs targeting pre-school populations at minimum cost.  相似文献   
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Background

We analyzed the association between 53 genes related to DNA repair and p53-mediated damage response and serous ovarian cancer risk using case-control data from the North Carolina Ovarian Cancer Study (NCOCS), a population-based, case-control study.

Methods/Principal Findings

The analysis was restricted to 364 invasive serous ovarian cancer cases and 761 controls of white, non-Hispanic race. Statistical analysis was two staged: a screen using marginal Bayes factors (BFs) for 484 SNPs and a modeling stage in which we calculated multivariate adjusted posterior probabilities of association for 77 SNPs that passed the screen. These probabilities were conditional on subject age at diagnosis/interview, batch, a DNA quality metric and genotypes of other SNPs and allowed for uncertainty in the genetic parameterizations of the SNPs and number of associated SNPs. Six SNPs had Bayes factors greater than 10 in favor of an association with invasive serous ovarian cancer. These included rs5762746 (median OR(odds ratio)per allele = 0.66; 95% credible interval (CI) = 0.44–1.00) and rs6005835 (median ORper allele  = 0.69; 95% CI  = 0.53–0.91) in CHEK2, rs2078486 (median ORper allele  = 1.65; 95% CI = 1.21–2.25) and rs12951053 (median ORper allele  = 1.65; 95% CI = 1.20–2.26) in TP53, rs411697 (median OR rare homozygote  = 0.53; 95% CI  = 0.35 – 0.79) in BACH1 and rs10131 (median OR rare homozygote  =  not estimable) in LIG4. The six most highly associated SNPs are either predicted to be functionally significant or are in LD with such a variant. The variants in TP53 were confirmed to be associated in a large follow-up study.

Conclusions/Significance

Based on our findings, further follow-up of the DNA repair and response pathways in a larger dataset is warranted to confirm these results.  相似文献   
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