2,412 research outputs found
Reduced Susceptibility to Two-Stage Skin Carcinogenesis in Mice with Epidermis-Specific Deletion of Cd151
Altered expression of the tetraspanin CD151 is associated with skin tumorigenesis; however, whether CD151 is causally involved in the tumorigenic process is not known. To evaluate its role in tumor formation, we subjected epidermis-specific Cd151 knockout mice to chemical skin carcinogenesis. Mice lacking epidermal Cd151 developed fewer and smaller tumors than wild-type mice after treatment with 7,12-dimethylbenzanthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA). Furthermore, Cd151-null epidermis showed a reduced hyperproliferative response to short-term treatment with TPA as compared with wild-type skin, whereas epidermal turnover was increased. Tumors were formed in equal numbers after DMBA-only treatment. We suggest that DMBA-initiated keratinocytes lacking Cd151 leave their niches in the epidermis and hair follicles in response to TPA treatment and subsequently are lost by differentiation. Because genetic ablation of Itga3 also reduced skin tumor formation, we tested whether reduced expression of α3 could further suppress tumor formation in epidermis-specific Cd151 knockout mice. Although DMBA/TPA-induced formation of skin tumors was similar in compound heterozygotes for Cd151 and Itga3 to that in wild-type mice, heterozygosity for Itga3 on a Cd151-null background diminished tumorigenesis, suggesting genetic interaction between the two genes. We thus identify CD151 as a critical factor in TPA-dependent skin carcinogenesis
A Fully Coupled Model of Multi-Chip Press-Pack IGBT for Thermo-Mechanical Stress Distribution Prediction
Lack of evidence of hepatitis in patients with oral lichen planus in China: a case control study
Background: China has been one of the countries with high prevalence of chronic hepatitis B virus (HBV) and
hepatitis C virus (HCV) liver disease. And lichen planus is an extrahepatic manifestation of patients with chronic
HCV infection. This case-control study was conducted to investigate the relationship between oral lichen planus
(OLP) and HBV/HCV infection in China.
Material and Methods: A total of 776 patients, including 150 patients with OLP (Group OLP), 429 inpatients from
the Trauma Ward of Oral and Maxillofacial Surgery Department (Group A), 110 patients with other oral mucosal
diseases, but without a reported association with HCV infection (Group B) and 87 patients with oral lichenoid lesion
(Group OLL), were compared with their seroprevalence of anti-HCV antibody (HCVAb), hepatitis B surface
antigen (HBsAg) and the parameters of liver functions. Moreover, the clinical characteristics of OLP were also
observed, such as gender, age, chief complaint, course of the disease, clinical type, sites involved and so on.
Results: The positive rates of HCVAb and HBsAg in OLP patients were 0.7% and 4%, respectively. Neither HCVAb
nor HBsAg was associated with OLP as demonstrated by both the univariate and the multivariate analyses.
The clinical features and liver functions of OLP patients with negative or positive HBsAg were nearly the same.
Conclusions: Our findings verify that there is no association between OLP and hepatitis and there is no need to run
a screening test for HCV or HBV in OLP patients in Chin
The Association between Individual SNPs or Haplotypes of Matrix Metalloproteinase 1 and Gastric Cancer Susceptibility, Progression and Prognosis
BACKGROUND: The single nucleotide polymorphisms (SNPs) in matrix metalloproteinase 1(MMP-1) play important roles in some cancers. This study examined the associations between individual SNPs or haplotypes in MMP-1 and susceptibility, clinicopathological parameters and prognosis of gastric cancer in a large sample of the Han population in northern China. METHODS: In this case-controlled study, there were 404 patients with gastric cancer and 404 healthy controls. Seven SNPs were genotyped using the MALDI-TOF MS system. Then, SPSS software, Haploview 4.2 software, Haplo.states software and THEsias software were used to estimate the association between individual SNPs or haplotypes of MMP-1 and gastric cancer susceptibility, progression and prognosis. RESULTS: Among seven SNPs, there were no individual SNPs correlated to gastric cancer risk. Moreover, only the rs470206 genotype had a correlation with histologic grades, and the patients with GA/AA had well cell differentiation compared to the patients with genotype GG (OR=0.573; 95%CI: 0.353-0.929; P=0.023). Then, we constructed a four-marker haplotype block that contained 4 common haplotypes: TCCG, GCCG, TTCG and TTTA. However, all four common haplotypes had no correlation with gastric cancer risk and we did not find any relationship between these haplotypes and clinicopathological parameters in gastric cancer. Furthermore, neither individual SNPs nor haplotypes had an association with the survival of patients with gastric cancer. CONCLUSIONS: This study evaluated polymorphisms of the MMP-1 gene in gastric cancer with a MALDI-TOF MS method in a large northern Chinese case-controlled cohort. Our results indicated that these seven SNPs of MMP-1 might not be useful as significant markers to predict gastric cancer susceptibility, progression or prognosis, at least in the Han population in northern China
Gene expression regulation by the Chromodomain helicase DNA-binding protein 9 (CHD9) chromatin remodeler is dispensable for murine development.
Chromodomain helicase DNA-binding (CHD) chromatin remodelers regulate transcription and DNA repair. They govern cell-fate decisions during embryonic development and are often deregulated in human pathologies. Chd1-8 show upon germline disruption pronounced, often developmental lethal phenotypes. Here we show that contrary to Chd1-8 disruption, Chd9-/-animals are viable, fertile and display no developmental defects or disease predisposition. Germline deletion of Chd9 only moderately affects gene expression in tissues and derived cells, whereas acute depletion in human cancer cells elicits more robust changes suggesting that CHD9 is a highly context-dependent chromatin regulator that, surprisingly, is dispensable for mouse development
Preparation of Nitrogen-Doped Carbon Material from Monosodium Glutamate and Its Catalytic Performance
N-doped carbon materials (NCMs) are generally used as electrode materials, and seldom used as catalysts in chemical reaction. In this work, NCMs were prepared by high-temperature pyrolysis using monosodium glutamate as sources of both carbon and nitrogen, magnesium acetate as a porogen, and nickel hydroxide as a graphitization catalyst. The catalytic performance of NCMs was investigated in the reduction of 4-nitrophenol (4-NP) with potassium borohydride at 30 ºC. As metal-free catalysts, all of the NCMs can catalyze the reaction. The graphitization degree and N-doped amount of NCM have a great influence on the catalytic activity. The NCM annealed at 800 ºC has higher activity and stability. The reaction rate constant can reach 0.57 min-1, and the activation energy was about 36.4 kJ/mol. Copyright © 2019 BCREC Group. All rights reserve
Recombination frequencies between cultivated soybean (Glycine max) and its wild relative Glycine soja based on molecular marker analysis
Close relatives of cultivated crops provide an invaluable source of genetic variation in crop improvement and exploiting such variation often forms a critical part in a breeding program. The usability of the wild soybean Glycine soja was investigated in this study by analyzing populations derived from two wide crosses between a common cultivar and two different G. soja accessions using simple sequence repeat (SSR) markers. Consistent reductions in recombination frequencies were not detected in either of these two wide crosses and the results does not seem to be confined to the particular populations or the wild genotypes used. In variance with previous reports that domestication-related traits are often controlled by one or two major loci, these recombination results strongly indicate that linkage drag should not be a major concern in transferring genes from the wild taxon into the cultigen, although backcross would still be required to minimize undesirable chromatins.Keywords: Glycine max, Glycine soja, linkage drags, recombination frequency, molecular markersAfrican Journal of Biotechnology Vol. 12(22), pp. 3522-352
Development of oxygen insensitivity of the quantitative histochemical assay of G6PDH activity during colorectal carcinogenesis
Development of oxygen insensitivity of the quantitative histochemical assay of G6PDH activity during colorectal carcinogenesis
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