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821.
Kristin L. Krueger Evan Chwa Alexandria S. Peterson John C. Willman Alex Fok Bonita van Heel Young Heo Michael Weston Ralph DeLong 《American journal of physical anthropology》2021,176(4):703-712
Dental microwear formation on the posterior dentition is largely attributed to an organism's diet. However, some have suggested that dietary and environmental abrasives contribute more to the formation process than food, calling into question the applicability of dental microwear to the reconstruction of diet in the fossil record. Creating microwear under controlled conditions would benefit this debate, but requires accurately replicating the oral environment. This study tests the applicability of Artificial Resynthesis Technology (ART 5) to create microwear textures while mitigating the challenges of past research. ART 5 is a simulator that replicates the chewing cycle, responds to changes in food texture, and simulates the actions of the oral cavity. Surgically extracted, occluding pairs of third molars (n = 2 pairs) were used in two chewing experiments: one with dried beef and another with sand added to the dried beef. High-resolution molds were taken at 0, 50, 100, 2500, and 5000 simulated chewing cycles, which equates to approximately 1 week of chewing. Preliminary results show that ART 5 produces microwear textures. Meat alone may produce enamel prism rod exposure at 5000 cycles, although attrition cannot be ruled out. Meat with sand accelerates the wear formation process, with enamel prism rods quickly obliterated and “pit-and-scratch” microwear forming at approximately 2500 cycles. Future work with ART 5 will incorporate a more thorough experimental protocol with improved controls, pH of the simulated oral environment, and grit measurements; however, these results indicate the potential of ART 5 in untangling the complex variables of dental microwear formation. 相似文献
822.
Ji Hoon Kim Bo Hwa Sohn Hyun-Sung Lee Sang-Bae Kim Jeong Eun Yoo Yun-Yong Park Woojin Jeong Sung Sook Lee Eun Sung Park Ahmed Kaseb Baek Hui Kim Wan Bae Kim Jong Eun Yeon Kwan Soo Byun In-Sun Chu Sung Soo Kim Xin Wei Wang Snorri S. Thorgeirsson John M. Luk Koo Jeong Kang Jeonghoon Heo Young Nyun Park Ju-Seog Lee 《PLoS medicine》2014,11(12)
Background
Typically observed at 2 y after surgical resection, late recurrence is a major challenge in the management of hepatocellular carcinoma (HCC). We aimed to develop a genomic predictor that can identify patients at high risk for late recurrence and assess its clinical implications.Methods and Findings
Systematic analysis of gene expression data from human liver undergoing hepatic injury and regeneration revealed a 233-gene signature that was significantly associated with late recurrence of HCC. Using this signature, we developed a prognostic predictor that can identify patients at high risk of late recurrence, and tested and validated the robustness of the predictor in patients (n = 396) who underwent surgery between 1990 and 2011 at four centers (210 recurrences during a median of 3.7 y of follow-up). In multivariate analysis, this signature was the strongest risk factor for late recurrence (hazard ratio, 2.2; 95% confidence interval, 1.3–3.7; p = 0.002). In contrast, our previously developed tumor-derived 65-gene risk score was significantly associated with early recurrence (p = 0.005) but not with late recurrence (p = 0.7). In multivariate analysis, the 65-gene risk score was the strongest risk factor for very early recurrence (<1 y after surgical resection) (hazard ratio, 1.7; 95% confidence interval, 1.1–2.6; p = 0.01). The potential significance of STAT3 activation in late recurrence was predicted by gene network analysis and validated later. We also developed and validated 4- and 20-gene predictors from the full 233-gene predictor. The main limitation of the study is that most of the patients in our study were hepatitis B virus–positive. Further investigations are needed to test our prediction models in patients with different etiologies of HCC, such as hepatitis C virus.Conclusions
Two independently developed predictors reflected well the differences between early and late recurrence of HCC at the molecular level and provided new biomarkers for risk stratification. Please see later in the article for the Editors'' Summary 相似文献823.
Sung-Mok Lee Won-Kyung Hong Sun-Yeon Heo Jang Min Park You Ree Jung Baek-Rock Oh Min-Ho Joe Jeong-Woo Seo Chul Ho Kim 《Journal of industrial microbiology & biotechnology》2014,41(8):1259-1266
The acetolactate synthase (als)-deficient mutant of Klebsiella pneumoniae fails to produce 1,3-propanediol (1,3-PD) or 2,3-butanediol (2,3-BD), and is defective in glycerol metabolism. In an effort to recover production of the industrially valuable 1,3-PD, we introduced the Zymomonas mobilis pyruvate decarboxylase (pdc) and aldehyde dehydrogenase (aldB) genes into the als-deficient mutant to activate the conversion of pyruvate to ethanol. Heterologous expression of pdc and aldB efficiently recovered glycerol metabolism in the 2,3-BD synthesis-defective mutant, enhancing the production of 1,3-PD by preventing the accumulation of pyruvate. Production of 1,3-PD in the pdc- and aldB-expressing als-deficient mutant was further enhanced by increasing the aeration rate. This system uses metabolic engineering to produce 1,3-PD while minimizing the generation of 2,3-BD, offering a breakthrough for the industrial production of 1,3-PD from crude glycerol. 相似文献
824.
825.
Seong Gu Heo Joo-Yeon Hwang Saangyong Uhmn Min Jin Go Burmseok Oh Jong-Young Lee Ji Wan Park 《Human genetics》2014,133(3):311-319
Genetic risk factors for hypertension may have age or gender specificity and pleiotropic effects. This study aims to measure the risk of genetic and non-genetic factors in the occurrence of hypertension and related diseases, with consideration of potential confounding factors and age-gender stratification. A discovery set of 352,228 genotyped plus 1.8 million imputed single-nucleotide polymorphisms were analyzed for 2,886 hypertensive cases and 3,440 healthy controls obtained from two community-based cohorts in Korea, and selected gene variants were replicated in the Health Examinee cohort (665 cases and 1,285 controls). Genome-wide association analyses were conducted in 12 groups stratified by age and gender after adjusting for potential covariates under three genetic models. Age, rural area residence, body mass index, family history of hypertension, male gender, current alcohol drinking status, and current smoking status were significantly associated with hypertension (P = 4 × 10?151 to 0.011). Five gene variants, rs11066280 (C12orf51), rs12229654 and rs3782889 (MYL2), rs2072134 (OAS3), rs2093395 (TREML2), and rs17249754 (ATP2B1), were found to be associated with hypertension mostly in men (P = 4.76 × 10?14 to 4.46 × 10?7 in the joint analysis); three SNPs (rs11066280, rs12229654, and rs3782889) remained significant after Bonferroni correction in an independent population. Three gene variants, rs12229654, rs17249754, and rs11066280, were significantly associated with metabolic disorders such as hyperlipidemia and diabetes (P = 0.00071 to 0.0097, respectively). Careful consideration of the potential confounding effects in future genome-wide association studies is necessary to uncover the genetic underpinnings of complex diseases. 相似文献
826.
827.
Jong-Ho Cha Hee-Jun Wee Ji Hae Seo Bum Ju Ahn Ji-Hyeon Park Jun-Mo Yang Sae-Won Lee Eun Hee Kim Ok-Hee Lee Ji Hoe Heo Hyo-Jong Lee Irwin H. Gelman Ken Arai Eng H. Lo Kyu-Won Kim 《PloS one》2014,9(4)
The repair process after CNS injury shows a well-organized cascade of three distinct stages: inflammation, new tissue formation, and remodeling. In the new tissue formation stage, various cells migrate and form the fibrotic scar surrounding the lesion site. The fibrotic scar is known as an obstacle for axonal regeneration in the remodeling stage. However, the role of the fibrotic scar in the new tissue formation stage remains largely unknown. We found that the number of A-kinase anchoring protein 12 (AKAP12)-positive cells in the fibrotic scar was increased over time, and the cells formed a structure which traps various immune cells. Furthermore, the AKAP12-positive cells strongly express junction proteins which enable the structure to function as a physical barrier. In in vivo validation, AKAP12 knock-out (KO) mice showed leakage from a lesion, resulting from an impaired structure with the loss of the junction complex. Consistently, focal brain injury in the AKAP12 KO mice led to extended inflammation and more severe tissue damage compared to the wild type (WT) mice. Accordingly, our results suggest that AKAP12-positive cells in the fibrotic scar may restrict excessive inflammation, demonstrating certain mechanisms that could underlie the beneficial actions of the fibrotic scar in the new tissue formation stage during the CNS repair process. 相似文献
828.
Anna E van der Windt Esther Haak Ruud HJ Das Nicole Kops Tim JM Welting Marjolein MJ Caron Niek P van Til Jan AN Verhaar Harrie Weinans Holger Jahr 《Arthritis research & therapy》2010,12(3):R100
Introduction
Chondrocytes experience a hypertonic environment compared with plasma (280 mOsm) due to the high fixed negative charge density of cartilage. Standard isolation of chondrocytes removes their hypertonic matrix, exposing them to nonphysiological conditions. During in vitro expansion, chondrocytes quickly lose their specialized phenotype, making them inappropriate for cell-based regenerative strategies. We aimed to elucidate the effects of tonicity during isolation and in vitro expansion on chondrocyte phenotype. 相似文献829.
Lee BS Heo J Kim YM Shim SM Pae HO Kim YM Chung HT 《Biochemical and biophysical research communications》2006,343(3):965-972
Carbon monoxide (CO) and nitric oxide (NO) are two gas molecules which have cytoprotective functions against oxidative stress and inflammatory responses in many cell types. Currently, it is known that NO produced by nitric oxide synthase (NOS) induces heme oxygenase 1 (HO1) expression and CO produced by the HO1 inhibits inducible NOS expression. Here, we first show CO-mediated HO1 induction and its possible mechanism in human hepatocytes. Exposure of HepG2 cells or primary hepatocytes to CO resulted in dramatic induction of HO1 in dose- and time-dependent manner. The CO-mediated HO1 induction was abolished by MAP kinase inhibitors (MAPKs) but not affected by inhibitors of PI3 kinase or NF-kappaB. In addition, CO induced the nuclear translocation and accumulation of Nrf2, which suppressed by MAPKs inhibitors. Taken together, we suggest that CO induces Nrf2 activation via MAPKs signaling pathways, thereby resulting in HO1 expression in HepG2 cells. 相似文献
830.
Martin HJ Busch Wolfgang Vollmann Dietrich HW Grönemeyer 《Biomedical engineering online》2006,5(1):35-20