942 resultados para Genomic banks
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Herein we provide a detailed molecular analysis of the spatial heterogeneity of clinically localized, multifocal prostate cancer to delineate new oncogenes or tumor suppressors. We initially determined the copy number aberration (CNA) profiles of 74 patients with index tumors of Gleason score 7. Of these, 5 patients were subjected to whole-genome sequencing using DNA quantities achievable in diagnostic biopsies, with detailed spatial sampling of 23 distinct tumor regions to assess intraprostatic heterogeneity in focal genomics. Multifocal tumors are highly heterogeneous for single-nucleotide variants (SNVs), CNAs and genomic rearrangements. We identified and validated a new recurrent amplification of MYCL, which is associated with TP53 deletion and unique profiles of DNA damage and transcriptional dysregulation. Moreover, we demonstrate divergent tumor evolution in multifocal cancer and, in some cases, tumors of independent clonal origin. These data represent the first systematic relation of intraprostatic genomic heterogeneity to predicted clinical outcome and inform the development of novel biomarkers that reflect individual prognosis.
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PURPOSE The implementation of genomic-based medicine is hindered by unresolved questions regarding data privacy and delivery of interpreted results to health-care practitioners. We used DNA-based prediction of HIV-related outcomes as a model to explore critical issues in clinical genomics. METHODS We genotyped 4,149 markers in HIV-positive individuals. Variants allowed for prediction of 17 traits relevant to HIV medical care, inference of patient ancestry, and imputation of human leukocyte antigen (HLA) types. Genetic data were processed under a privacy-preserving framework using homomorphic encryption, and clinical reports describing potentially actionable results were delivered to health-care providers. RESULTS A total of 230 patients were included in the study. We demonstrated the feasibility of encrypting a large number of genetic markers, inferring patient ancestry, computing monogenic and polygenic trait risks, and reporting results under privacy-preserving conditions. The average execution time of a multimarker test on encrypted data was 865 ms on a standard computer. The proportion of tests returning potentially actionable genetic results ranged from 0 to 54%. CONCLUSIONS The model of implementation presented herein informs on strategies to deliver genomic test results for clinical care. Data encryption to ensure privacy helps to build patient trust, a key requirement on the road to genomic-based medicine.Genet Med advance online publication 14 January 2016Genetics in Medicine (2016); doi:10.1038/gim.2015.167.
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Genome alignment of a macrolide, lincosamide, and streptogramin B (MLSB)-resistant Staphylococcus fleurettii strain with an MLSB-susceptible S. fleurettii strain revealed a novel 11,513-bp genomic island carrying the new erythromycin resistance methylase gene erm(45). This gene was shown to confer inducible MLSB resistance when cloned into Staphylococcus aureus. The erm(45)-containing island was integrated into the housekeeping gene guaA in S. fleurettii and was able to form a circular intermediate but was not transmissible to S. aureus.
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Mortality owing to liver cancer has increased in the past 20 years, and the latest estimates indicate that the global health burden of this disease will continue to grow. Most patients with hepatocellular carcinoma (HCC) are still diagnosed at intermediate or advanced disease stages, where curative approaches are often not feasible. Among the treatment options available, the molecular targeted agent sorafenib is able to significantly increase overall survival in these patients. Thereafter, up to seven large, randomized phase III clinical trials investigating other molecular therapies in the first-line and second-line settings have failed to improve on the results observed with this agent. Potential reasons for this include intertumour heterogeneity, issues with trial design and a lack of predictive biomarkers of response. During the past 5 years, substantial advances in our knowledge of the human genome have provided a comprehensive picture of commonly mutated genes in patients with HCC. This knowledge has not yet influenced clinical decision-making or current clinical practice guidelines. In this Review the authors summarize the molecular concepts of progression, discuss the potential reasons for clinical trial failure and propose new concepts of drug development, which might lead to clinical implementation of emerging targeted agents.
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Aeromonas salmonicida subsp. salmonicida is the causal agent of furunculosis in salmonids. We recently identified a group of genomic islands (AsaGEI) in this bacterium. AsaGEI2a, one of these genomic islands, has almost exclusively been identified in isolates from North America. To date, Aeromonas salmonicida subsp. salmonicida JF3224, a strain isolated from a wild brown trout (Salmo trutta) caught in Switzerland, was the only European isolate that appeared to bear AsaGEI2a. We analyzed the genome of JF3224 and showed that the genomic island in JF3224 is a new variant of AsaGEI, which we have called AsaGEI2b. While AsaGEI2b shares the same integrase gene and insertion site as AsaGEI2a, it is very different in terms of many other features. Additional genomic investigations combined with PCR genotyping revealed that JF3224 is sensitive to growth at 25°C, leading to insertion sequence-dependent rearrangement of the locus on the pAsa5 plasmid that encodes a type three secretion system, which is essential for the virulence of the bacterium. The analysis of the JF3224 genome confirmed that AsaGEIs are accurate indicators of the geographic origins of A. salmonicida subsp. salmonicida isolates and is another example of the susceptibility of the pAsa5 plasmid to DNA rearrangements.
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Localized prostate cancer (PCa) is a clinically heterogeneous disease, which presents with variability in patient outcomes within the same risk stratification (low, intermediate or high) and even within the same Gleason scores. Genomic tools have been developed with the purpose of stratifying patients affected by this disease to help physicians personalize therapies and follow-up schemes. This review focuses on these tissue-based tools. At present, four genomic tools are commercially available: Decipher™, Oncotype DX®, Prolaris® and ProMark®. Decipher™ is a tool based on 22 genes and evaluates the risk of adverse outcomes (metastasis) after radical prostatectomy (RP). Oncotype DX® is based on 17 genes and focuses on the ability to predict outcomes (adverse pathology) in very low-low and low-intermediate PCa patients, while Prolaris® is built on a panel of 46 genes and is validated to evaluate outcomes for patients at low risk as well as patients who are affected by high risk PCa and post-RP. Finally, ProMark® is based on a multiplexed proteomics assay and predicts PCa aggressiveness in patients found with similar features to Oncotype DX®. These biomarkers can be helpful for post-biopsy decision-making in low risk patients and post-radical prostatectomy in selected risk groups. Further studies are needed to investigate the clinical benefit of these new technologies, the financial ramifications and how they should be utilized in clinics.
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The inhibitory effects of VSV infection on MuLV production were investigated using the VSV temperature-sensitive mutants t1B17(I & V), tsT1026(I), tsG22(II), and ts052(II). At the permissive temperature, all four mutants suppressed the release of virion-associated MuLV gRNA by approximately 98% within 0.5 to 2.5 hr post infection. At the restrictive temperature and in the absence of cell killing, infection with t1B17(I & V) inhibited the release of MuLV gRNA, while tsT1026(I) and tsG22(II) did not. In contrast, ts052(II) inhibited the release of MuLV gRNA and induced cell killing. During the same time period and at either temperature, all four mutants did not suppress either MuLV-associated protein release or intracellular MuLV sRNA synthesis. These results indicate that VSV inhibits MULV gRNA release at a level somewhere between the synthesis and release of newly synthesized gRNA.^
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The capital structure and regulation of financial intermediaries is an important topic for practitioners, regulators and academic researchers. In general, theory predicts that firms choose their capital structures by balancing the benefits of debt (e.g., tax and agency benefits) against its costs (e.g., bankruptcy costs). However, when traditional corporate finance models have been applied to insured financial institutions, the results have generally predicted corner solutions (all equity or all debt) to the capital structure problem. This paper studies the impact and interaction of deposit insurance, capital requirements and tax benefits on a bankÇs choice of optimal capital structure. Using a contingent claims model to value the firm and its associated claims, we find that there exists an interior optimal capital ratio in the presence of deposit insurance, taxes and a minimum fixed capital standard. Banks voluntarily choose to maintain capital in excess of the minimum required in order to balance the risks of insolvency (especially the loss of future tax benefits) against the benefits of additional debt. Because we derive a closed- form solution, our model provides useful insights on several current policy debates including revisions to the regulatory framework for GSEs, tax policy in general and the tax exemption for credit unions.
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India's public sector banks (PSBs) are compared unfavorably with their private sector counterparts, domestic and foreign. This comparison rests, for the most part, on financial measures of performance, and such a comparison provides much of the rationale for privatization of PSBs.In this paper, we attempt a comparison between PSBs and their private sector counterparts based on measures of productivity that use quantities of outputs and inputs. We employ two measures of productivity: Tornqvist and Malmquist total factor productivity growth. We attempt these comparisons over the period 1992-2000, comparing PSBs with both domestic private and foreign banks. Out of a total of four comparisons we have made, there are no differences in three cases, PSBs do better in two, and foreign banks in one. To put it differently, PSBs are seen to be at a disadvantage in only one out of six comparisons. It is difficult, therefore, to sustain the proposition that efficiency and productivity have been lower in public sector banks relative to their peers in the private sector.
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This paper considers the performance of banks, domestic and foreign, in Korea prior to, during, and immediately after the Asian financial crisis, examining how the profitability of those banks differed and identifying factors that explain why those differences existed. The performance of Korean banks deteriorated dramatically in 1998 with most banks recovering somewhat in 1999. Foreign banks did not experience the same negative effect on their returns on assets and equity as a rule. Several standard findings emerge. For example, equity to assets correlates positively with domestic, but not foreign, bank performance, as measured by the returns on assets and equity, even when the government recapitalized institutions that were performing quite badly. Also, foreign-currency deposits significantly and negatively correlate with domestic Korean bank performance, although only in the post-crisis period for regional banks. In sum, the domestic Korean banks suffered more severely from the Asian financial crisis than foreign banks.
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The Asian financial crisis spread its effect quickly across a number of countries. Korea faced serious problems in her financial and corporate sectors. This paper considers the performance of Korean nationwide banks before, during, and immediately after the Asian financial crisis. The performance of Korean nationwide banks took a big hit in 1998. Most banks recovered somewhat in 1999 with the notable exception of the further deterioration of Seoul. Several factors possess strong correlations with bank performance. Among other standard findings, equity to assets correlates positively with bank performance, even when the government recapitalized a number of institutions that performed poorly. The Asian crisis did not affect the normal rules of good bank management. The government, however, directly intervened in the banking sector on a large scale to limit the scope of the crisis in the Korean economy.
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Von Dr. Chr. Lindemann
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Prof. Dr. Wilh. Seelig
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There are many diseases associated with the expansion of DNA repeats in humans. Myotonic dystrophy type 2 is one of such diseases, characterized by expansions of a (CCTG)•(CAGG) repeat tract in intron 1 of zinc finger protein 9 (ZNF9) in chromosome 3q21.3. The DM2 repeat tract contains a flanking region 5' to the tract that consists of a polymorphic repetitive sequence (TG)14-25(TCTG)4-11(CCTG) n. The (CCTG)•(CAGG) repeat is typically 11-26 repeats in persons without the disease, but can expand up to 11,000 repeats in affected individuals, which is the largest expansion seen in DNA repeat diseases to date. This DNA tract remains one of the least characterized disease-associated DNA repeats, and mechanisms causing the repeat expansion in humans have yet to be elucidated. Alternative, non B-DNA structures formed by the expanded repeats are typical in DNA repeat expansion diseases. These sequences may promote instability of the repeat tracts. I determined that slipped strand structure formation occurs for (CCTG)•(CAGG) repeats at a length of 42 or more. In addition, Z-DNA structure forms in the flanking human sequence adjacent to the (CCTG)•(CAGG) repeat tract. I have also performed genetic assays in E. coli cells and results indicate that the (CCTG)•(CAGG) repeats are more similar to the highly unstable (CTG)•(CAG) repeat tracts seen in Huntington's disease and myotonic dystrophy type 1, than to those of the more stable (ATTCT)•(AGAAT) repeat tracts of spinocerebellar ataxia type 10. This instability, however, is RecA-independent in the (CCTG)•(CAGG) and (ATTCT)•(AGAAT) repeats, whereas the instability is RecA-dependent in the (CTG)•(CAG) repeats. Structural studies of the (CCTG)•(CAGG) repeat tract and the flanking sequence, as well as genetic selection assays may reveal the mechanisms responsible for the repeat instability in E. coli, and this may lead to a better understanding of the mechanisms contributing to the human disease state. ^