172 research outputs found
One-Step Synthesis of Gelatin-Conjugated Supramolecular Hydrogels for Dynamic Regulation of Adhesion Contact and Morphology of Myoblasts
Hydrogels possessing fine-adjustable and switchable elasticity emulate the mechanical microenvironments of biological cells, which are known to change dynamically during development and disease progression. In this study, a supramolecular hydrogel conjugated with gelatin side chains was synthesized. By systematically screening the molar fraction of supramolecular host/guest cross-linkers, Youngās modulus of the substrate was fine-adjusted to the level for myoblasts, E ā 10 kPa. CāCāā myoblasts reproducibly and firmly adhered to the gelatin-conjugated hydrogel via focal adhesion contacts consisting of integrin clusters, whereas only a few cells adhered to the gel without gelatin side chains. The elasticity of the gelatin-conjugated hydrogel was switchable to desired levels by simply adding and removing free guest molecules in appropriate concentrations without interfering with cell viability. Immunofluorescence confocal microscopy images of fixed cells confirmed the adaptation of focal adhesions and remodeling of actin cytoskeletons on the gelatin-conjugated hydrogel. Time-lapse phase-contrast images demonstrated the dynamic response of the cells, manifested in their morphology, to an abrupt change in the substrate elasticity. Gelatin-conjugated hydrogels with switchable elasticity enable the direct and reversible mechanical stimulation of cells in one step without tedious surface functionalization with adhesion ligands
DNA Damage Sensor Ī³
Background. Phosphorylated histone H2AX (Ī³-H2AX) is a potential regulator of DNA repair and is a useful tool for detecting DNA damage. To evaluate the clinical usefulness of Ī³-H2AX in hepatocellular carcinoma (HCC), we measured the level of Ī³-H2AX in HCC, dysplastic nodule, and nontumorous liver diseases. Methods. The level of Ī³-H2AX was measured by immunohistochemistry in fifty-eight HCC, 18 chronic hepatitis, 22 liver cirrhosis, and 19 dysplastic nodules. Appropriate cases were also examined by fluorescence analysis and western blotting. Results. All cases with chronic liver disease showed increased levels of Ī³-H2AX expression. In 40 (69.9%) of 58 cases with HCC, the labeling index (LI) of Ī³-H2AX was above 50% and was inversely correlated with the histological grade. Mean Ī³-H2AX LI was the highest in dysplastic nodule (74.1Ā±22.1%), which was significantly higher than HCC (P<0.005). Moreover, Ī³-H2AX was significantly increased in nontumorous tissues of HCC as compared with liver cirrhosis without HCC (62.5Ā±24.7%, from 5.1 to 96.0%, P<0.005). Conclusions. Ī³-H2AX was increased in the preneoplastic lesions of HCC and might be a useful biomarker for predicting the risk of HCC
Identification of risk factors for elevated serum IgG4 levels in subjects in a large-scale health checkup cohort study
Introduction: To allow the identification of IgG4-related disease (IgG4-RD) from a subclinical phase as it is important to understand the risk of elevated serum IgG4 levels. We planned to evaluate serum IgG4 levels in the participants of the Nagasaki Islands Study (NaIS), a large-scale health checkup cohort study.Methods: This study included 3,240 individuals who participated in the NaIS between 2016 and 2018 and consented to participate in the study. Serum IgG4, IgG, and IgE levels and human leukocyte antigen (HLA) genotyping results of the NaIS subjects as well as lifestyle habits and peripheral blood test results were analyzed. The magnetic bead panel assay (MBA) and the standard nephelometry immunoassay (NIA) were used to measure serum IgG4 levels. The data were evaluated using multivariate analysis to identify lifestyle and genetic factors associated with elevated serum IgG4 levels.Results: Serum IgG4 levels measured with the NIA and MBA showed a tight positive correlation between the two groups (correlation coefficient 0.942). The median age of the participants in the NaIS was 69 years [63ā77]. The median serum IgG4 level was 30.2 mg/dL [IQR 12.5ā59.8]. Overall, 1019 (32.1%) patients had a history of smoking. When the subjects were stratified into three groups based on the smoking intensity (pack-year), the serum IgG4 level was significantly higher among those with a higher smoking intensity. Accordingly, the multivariate analysis identified a significant relationship between smoking status and serum IgG4 elevation.Conclusion: In this study, smoking was identified as a lifestyle factor correlating positively with elevated serum IgG4 levels
Factor analysis for construct validity of a trunk impairment scale in Parkinsonās disease: a cross-sectional study
ObjectivesTo investigate the construct validity of the Trunk Impairment Scale (TIS), which was developed to assess trunk impairment in patients with stroke, in patients with Parkinsonās disease (PD).DesignThis retrospective, cross-sectional study enrolled consecutive PD inpatients. Correlation analysis was performed to clarify whether the TIS assessment was related to other balance functions, lower extremity muscle strength, or walking ability. Factor analysis was performed to see how the background factors of TIS differ from balance function, lower limb muscle strength, and walking ability.ResultsExamining the data of 471 patients with PD, there were relationships between TIS and the Mini-Balance Evaluation Systems Test (rā=ā0.67), Barthel Index (rā=ā0.57), general lower limb extension torque (rā=ā0.51), two-minute walk test (rā=ā0.54), Hoehn and Yahr stage (rā=āā0.61), and Movement Disorder Society Unified Parkinsonās Disease Rating Scale part III total points (rā=āā0.59). Factor analysis showed that TIS items were divided into three factors (an abdominal muscles and righting reflex component; a perception and verticality component; and a rotational component), differing from other scales that included clinical assessment items.ConclusionThe TIS can be useful for assessing the underlying trunk impairment as a basis for activities of daily living, gait function, and balance ability in patients with PD
Combined immunodeficiency and Epstein-Barr virus-induced B cell malignancy in humans with inherited CD70 deficiency
In this study, we describe four patients from two unrelated families of different ethnicities with a primary immunodeficiency, predominantly manifesting as susceptibility to Epstein-Barr virus (EBV)ārelated diseases. Three patients presented with EBV-associated Hodgkinās lymphoma and hypogammaglobulinemia; one also had severe varicella infection. The fourth had viral encephalitis during infancy. Homozygous frameshift or in-frame deletions in CD70 in these patients abolished either CD70 surface expression or binding to its cognate receptor CD27. Blood lymphocyte numbers were normal, but the proportions of memory B cells and EBV-specific effector memory CD8+ T cells were reduced. Furthermore, although T cell proliferation was normal, in vitroāgenerated EBV-specific cytotoxic T cell activity was reduced because of CD70 deficiency. This reflected impaired activation by, rather than effects during killing of, EBV-transformed B cells. Notably, expression of 2B4 and NKG2D, receptors implicated in controlling EBV infection, on memory CD8+ T cells from CD70-deficient individuals was reduced, consistent with their impaired killing of EBV-infected cells. Thus, autosomal recessive CD70 deficiency is a novel cause of combined immunodeficiency and EBV-associated diseases, reminiscent of inherited CD27 deficiency. Overall, human CD70āCD27 interactions therefore play a nonredundant role in T and B cellāmediated immunity, especially for protection against EBV and humoral immunity
Integrative Annotation of 21,037 Human Genes Validated by Full-Length cDNA Clones
The human genome sequence defines our inherent biological potential; the realization of the biology encoded therein requires knowledge of the function of each gene. Currently, our knowledge in this area is still limited. Several lines of investigation have been used to elucidate the structure and function of the genes in the human genome. Even so, gene prediction remains a difficult task, as the varieties of transcripts of a gene may vary to a great extent. We thus performed an exhaustive integrative characterization of 41,118 full-length cDNAs that capture the gene transcripts as complete functional cassettes, providing an unequivocal report of structural and functional diversity at the gene level. Our international collaboration has validated 21,037 human gene candidates by analysis of high-quality full-length cDNA clones through curation using unified criteria. This led to the identification of 5,155 new gene candidates. It also manifested the most reliable way to control the quality of the cDNA clones. We have developed a human gene database, called the H-Invitational Database (H-InvDB; http://www.h-invitational.jp/). It provides the following: integrative annotation of human genes, description of gene structures, details of novel alternative splicing isoforms, non-protein-coding RNAs, functional domains, subcellular localizations, metabolic pathways, predictions of protein three-dimensional structure, mapping of known single nucleotide polymorphisms (SNPs), identification of polymorphic microsatellite repeats within human genes, and comparative results with mouse full-length cDNAs. The H-InvDB analysis has shown that up to 4% of the human genome sequence (National Center for Biotechnology Information build 34 assembly) may contain misassembled or missing regions. We found that 6.5% of the human gene candidates (1,377 loci) did not have a good protein-coding open reading frame, of which 296 loci are strong candidates for non-protein-coding RNA genes. In addition, among 72,027 uniquely mapped SNPs and insertions/deletions localized within human genes, 13,215 nonsynonymous SNPs, 315 nonsense SNPs, and 452 indels occurred in coding regions. Together with 25 polymorphic microsatellite repeats present in coding regions, they may alter protein structure, causing phenotypic effects or resulting in disease. The H-InvDB platform represents a substantial contribution to resources needed for the exploration of human biology and pathology
Overexpression of flv3 improves photosynthesis in the cyanobacterium Synechocystis sp. PCC6803 by enhancement of alternative electron flow
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_Book summary_:
Experts are increasingly relied on in decision-making processes at international and European levels. Their involvement in those processes, however, is contested. This timely book on the role of 'experts' provides a broad-gauged analysis of the issues raised by their involvement in decision-making processes. The chapters explore three main recurring themes: the rationales for involving experts and ensuing legitimacy problems; the individual and collective dimensions of expert involvement in decision making; and experts and politics and the politics of expertise. With contributions from leading scholars and practitioners, they theorize the experts' involvement in general and address their role in the policy areas of environment, trade, human rights, migration, financial regulation, and agencification in the European Union
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