327 research outputs found
A Comparative Study of Patients’ Attitudes Toward Clinical Research in the United States and Urban and Rural China
As the number of clinical trials conducted in China increases, understanding Chinese attitudes toward clinical research is critical for designing effective and ethical studies. Two survey studies were conducted in 2012 and 2013 to compare patient attitudes toward clinical research and factors affecting research participation in the United States and urban and rural China. We surveyed 525 patients in 2012 (186 US, 186 urban, 153 rural China) and 690 patients in 2013 (412 US, 206 urban, 72 rural China). US patients were more likely to have no concerns regarding research participation than Chinese patients. Most common concerns of US patients were safety, privacy and confidentiality, and time required. Safety was a top concern for many Chinese. Chinese patients, particularly rural Chinese, were more concerned about the likelihood of self‐benefit, and receiving free medical care and financial incentive had greater influence on their participation. Being informed of the freedom to choose whether to participate or to leave a study was less important to Chinese patients. Our study provides important insights into Chinese patients' attitudes toward clinical research and the need to educate them about their rights. These findings help in designing cross‐cultural clinical studies that maximize enrollment while upholding Western ethical standards.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111170/1/cts12254.pd
Metabolomics Applied to Diabetes Research: Moving From Information to Knowledge
Type 2 diabetes is caused by a complex set ofinteractions between genetic and environmentalfactors. Recent work has shown that human type2 diabetes is a constellation of disorders associ-ated with polymorphisms in a wide array of genes, with each individual gene accounting for 1 % of disease risk (1). Moreover, type 2 diabetes involves dysfunction of multiple organ systems, including impaired insulin action in muscle and adipose, defective control of hepatic glu-cose production, and insulin deficiency caused by loss of -cell mass and function (2). This complexity presents challenges for a full understanding of the molecular path-ways that contribute to the development of this major disease. Progress in this area may be aided by the recent advent of technologies for comprehensive metabolic anal-ysis, sometimes termed “metabolomics. ” Herein, we sum-marize key metabolomics methodologies, including nuclear magnetic resonance (NMR) and mass spectrome
Single nucleotide polymorphisms of 8 inflammation-related genes and their associations with smoking-related cancers
Tobacco smoke and its metabolites are carcinogens that increase tissue oxidative stress and induce target tissue inflammation. We hypothesized that genetic variation of inflammatory pathway genes plays a role in tobacco-related carcinogenesis and is modified by tobacco smoking. We evaluated the association of 12 single nucleotide polymorphisms of 8 inflammation-related genes with tobacco-related cancers (lung, oropharynx, larynx, esophagus, stomach, liver, bladder, and kidney) using 3 case-control studies from: Los Angeles (population-based; 611 lung and 553 upper aero-digestive tract cancer cases and 1,040 controls), Taixing, China (population-based; 218 esophagus, 206 stomach, 204 liver cancer cases, and 415 controls), and Memorial Sloan-Kettering Cancer Center (hospital-based; 227 bladder cancer cases and 211 controls). After adjusting for age, education, ethnicity, gender, and tobacco smoking, IL10 rs1800871 was inversely associated with oropharyngeal cancer (CT+TT vs . CC adjusted odds ratio [aOR]: 0.69, 95% confidence interval [CI]: 0.50–0.95), and was positively associated with lung cancer among never smokers (TT vs . CT+CC aOR: 2.5, 95% CI: 1.3–5.1) and inversely with oropharyngeal cancer among ever smokers (CT+TT vs . CC aOR: 0.63, 95% CI: 0.41–0.95). Among all pooled never smokers (588 cases and 816 controls), TNF rs1799964 was inversely associated with smoking-related cancer (CC vs . CT+TT aOR: 0.36, 95% CI: 0.17–0.77). Bayesian correction for multiple comparisons suggests that chance is unlikely to explain our findings (although epigenetic mechanisms may be in effect), which support our hypotheses, suggesting that IL10 rs1800871 is a susceptibility marker for oropharyngeal and lung cancers, and that TNF rs1799964 is associated with smoking-related cancers among never smokers.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78055/1/25214_ftp.pd
Corrigendum: An ethnically relevant consensus Korean reference genome is a step towards personal reference genomes.
This corrects the article DOI: 10.1038/ncomms13637
Crystallography of a Lewis-Binding Norovirus, Elucidation of Strain-Specificity to the Polymorphic Human Histo-Blood Group Antigens
Noroviruses, an important cause of acute gastroenteritis in humans, recognize the histo-blood group antigens (HBGAs) as host susceptible factors in a strain-specific manner. The crystal structures of the HBGA-binding interfaces of two A/B/H-binding noroviruses, the prototype Norwalk virus (GI.1) and a predominant GII.4 strain (VA387), have been elucidated. In this study we determined the crystal structures of the P domain protein of the first Lewis-binding norovirus (VA207, GII.9) that has a distinct binding property from those of Norwalk virus and VA387. Co-crystallization of the VA207 P dimer with Ley or sialyl Lex tetrasaccharides showed that VA207 interacts with these antigens through a common site found on the VA387 P protein which is highly conserved among most GII noroviruses. However, the HBGA-binding site of VA207 targeted at the Lewis antigens through the α-1, 3 fucose (the Lewis epitope) as major and the β-N-acetyl glucosamine of the precursor as minor interacting sites. This completely differs from the binding mode of VA387 and Norwalk virus that target at the secretor epitopes. Binding pocket of VA207 is formed by seven amino acids, of which five residues build up the core structure that is essential for the basic binding function, while the other two are involved in strain-specificity. Our results elucidate for the first time the genetic and structural basis of strain-specificity by a direct comparison of two genetically related noroviruses in their interaction with different HBGAs. The results provide insight into the complex interaction between the diverse noroviruses and the polymorphic HBGAs and highlight the role of human HBGA as a critical factor in norovirus evolution
The Genome of the Netherlands: Design, and project goals
Within the Netherlands a national network of biobanks has been established (Biobanking and Biomolecular Research Infrastructure-Netherlands (BBMRI-NL)) as a national node of the European BBMRI. One of the aims of BBMRI-NL is to enrich biobanks with different types of molecular and phenotype data. Here, we describe the Genome of the Netherlands (GoNL), one of the projects within BBMRI-NL. GoNL is a whole-genome-sequencing project in a representative sample consisting of 250 trio-families from all provinces in the Netherlands, which aims to characterize DNA sequence variation in the Dutch population. The parent-offspring trios include adult individuals ranging in age from 19 to 87 years (mean=53 years; SD=16 years) from birth cohorts 1910-1994. Sequencing was done on blood-derived DNA from uncultured cells and accomplished coverage was 14-15x. The family-based design represents a unique resource to assess the frequency of regional variants, accurately reconstruct haplotypes by family-based phasing, characterize short indels and complex structural variants, and establish the rate of de novo mutational events. GoNL will also serve as a reference panel for imputation in the available genome-wide association studies in Dutch and other cohorts to refine association signals and uncover population-specific variants. GoNL will create a catalog of human genetic variation in this sample that is uniquely characterized with respect to micro-geographic location and a wide range of phenotypes. The resource will be made available to the research and medical community to guide the interpretation of sequencing projects. The present paper summarizes the global characteristics of the project
Doped graphenes in catalysis
[EN] Due to the availability and easy preparation, graphenes are currently under intense investigation for various applications in chemistry including their use as metal-free catalysts. The presence in low percentage of heteroatoms on the graphene sheet ("doping") has become a general strategy to modify the electron density, electrical conductivity and other properties of graphenes. The influence of doping can be reflected on the use of these materials in catalysis. After a brief introduction presenting the unique properties and features of graphenes and the reasons why they are suitable to be applicable in catalysis, the present review focuses on those reports describing the use of doped graphenes as metal-free catalyst or as support of metal nanoparticles, electro- and photo-catalysis is excluded. Preparation methods of doped graphenes and adequate characterization techniques providing important information, particularly with respect to the active site in catalysis, are briefly presented before the main body of the review describing common features and relevant examples of the use of doped graphenes in catalysis. Also general traits of graphenes of support of metal nanoparticles have been commented. The final section summarizes the main conclusions and provides our view future developments in the field. The purpose of the present review is not to provide an exhaustive account of all the existing literature, but rather to introduce the reader in the opportunities and advantages that doped graphenes offer with regard to the use either as metal free catalyst or support of metal nanoparticles.Albero, J.; García Gómez, H. (2015). Doped graphenes in catalysis. Journal of Molecular Catalysis A: Chemical. 408:296-309. doi:10.1016/j.molcata.2015.06.011S29630940
Mammalian MCM Loading in Late-G1 Coincides with Rb Hyperphosphorylation and the Transition to Post-Transcriptional Control of Progression into S-Phase
BACKGROUND: Control of the onset of DNA synthesis in mammalian cells requires the coordinated assembly and activation of the pre-Replication Complex. In order to understand the regulatory events controlling preRC dynamics, we have investigated how the timing of preRC assembly relates temporally to other biochemical events governing progress into S-phase. METHODOLOGY/PRINCIPAL FINDING: In murine and Chinese hamster (CHO) cells released from quiescence, the loading of the replicative MCM helicase onto chromatin occurs in the final 3-4 hrs of G(1). Cdc45 and PCNA, both of which are required for G(1)-S transit, bind to chromatin at the G(1)-S transition or even earlier in G(1), when MCMs load. An RNA polymerase II inhibitor (DRB) was added to synchronized murine keratinocytes to show that they are no longer dependent on new mRNA synthesis 3-4 hrs prior to S-phase entry, which is also true for CHO and human cells. Further, CHO cells can progress into S-phase on time, and complete S-phase, under conditions where new mRNA synthesis is significantly compromised, and such mRNA suppression causes no adverse effects on preRC dynamics prior to, or during, S-phase progression. Even more intriguing, hyperphosphorylation of Rb coincides with the start of MCM loading and, paradoxically, with the time in late-G(1) when de novo mRNA synthesis is no longer rate limiting for progression into S-phase. CONCLUSIONS/SIGNIFICANCE: MCM, Cdc45, and PCNA loading, and the subsequent transit through G(1)-S, do not depend on concurrent new mRNA synthesis. These results indicate that mammalian cells pass through a distinct transition in late-G(1) at which time Rb becomes hyperphosphorylated and MCM loading commences, but that after this transition the control of MCM, Cdc45, and PCNA loading and the onset of DNA replication are regulated at the post-transcriptional level
Heterogeneous catalysis for sustainable biodiesel production via esterification and transesterification
Concern over the economics of accessing fossil fuel reserves, and widespread acceptance of the anthropogenic origin of rising CO2 emissions and associated climate change from combusting such carbon sources, is driving academic and commercial research into new routes to sustainable fuels to meet the demands of a rapidly rising global population. Here we discuss catalytic esterification and transesterification solutions to the clean synthesis of biodiesel, the most readily implemented and low cost, alternative source of transportation fuels to meet future societal demands
Cdc45 Limits Replicon Usage from a Low Density of preRCs in Mammalian Cells
Little is known about mammalian preRC stoichiometry, the number of preRCs on chromosomes, and how this relates to replicon size and usage. We show here that, on average, each 100-kb of the mammalian genome contains a preRC composed of approximately one ORC hexamer, 4–5 MCM hexamers, and 2 Cdc6. Relative to these subunits, ∼0.35 total molecules of the pre-Initiation Complex factor Cdc45 are present. Thus, based on ORC availability, somatic cells contain ∼70,000 preRCs of this average total stoichiometry, although subunits may not be juxtaposed with each other. Except for ORC, the chromatin-bound complement of preRC subunits is even lower. Cdc45 is present at very low levels relative to the preRC subunits, but is highly stable, and the same limited number of stable Cdc45 molecules are present from the beginning of S-phase to its completion. Efforts to artificially increase Cdc45 levels through ectopic expression block cell growth. However, microinjection of excess purified Cdc45 into S-phase nuclei activates additional replication foci by three-fold, indicating that Cdc45 functions to activate dormant preRCs and is rate-limiting for somatic replicon usage. Paradoxically, although Cdc45 colocalizes in vivo with some MCM sites and is rate-limiting for DNA replication to occur, neither Cdc45 nor MCMs colocalize with active replication sites. Embryonic metazoan chromatin consists of small replicons that are used efficiently via an excess of preRC subunits. In contrast, somatic mammalian cells contain a low density of preRCs, each containing only a few MCMs that compete for limiting amounts of Cdc45. This provides a molecular explanation why, relative to embryonic replicon dynamics, somatic replicons are, on average, larger and origin efficiency tends to be lower. The stable, continuous, and rate-limiting nature of Cdc45 suggests that Cdc45 contributes to the staggering of replicon usage throughout S-phase, and that replicon activation requires reutilization of existing Cdc45 during S-phase
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