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991.
992.
Hung-Chieh Chou Chiang-Ting Chien Po-Nien Tsao Wu-Shiun Hsieh Chien-Yi Chen Mei-Hwei Chang 《PloS one》2014,9(1)
Background
We hypothesized that cord blood hydrogen peroxide (H2O2) could be utilized to predict the severity of neonatal hyperbilirubinemia.Methods
We prospectively enrolled term or near-term healthy neonates. Cord blood and capillary blood at three days of age were measured for hydrogen peroxide and bilirubin concentrations. For newborns with hyperbilirubinemia, further blood samples were obtained at five and seven days of age. Newborns were divided into severe or less severe hyperbilirubinemic groups (peak bilirubin ≥17 mg/dL or not). The sensitivity, specificity, and negative predictive values were determined.Results
There were 158 neonates enrolled. The incidence of neonatal hyperbilirubinemia was 30.5% for a concentration ≥15 mg/dl. The rising patterns were similar among bilirubin concentrations and hydrogen peroxide levels during the first few days of life. There was a strong positive correlation between bilirubin concentrations and hydrogen peroxide levels after correlation analysis. The rate of severe hyperbilirubinemia was 13.3%. It revealed that a cord blood hydrogen peroxide signal level of 2500 counts/10 seconds was an appropriate cut-off for predicting severe hyperbilirubinemia. Sensitivity and the negative predictive value were 76.2% and 93.3%, respectively.Conclusions
Our findings confirm that hydrogen peroxide levels and bilirubin concentrations in cord and neonatal blood are closely related. A cord blood hydrogen peroxide level above 2500 counts/10 seconds associated with a high predictive value for severe hyperbilirubinemia. This method provides information about which neonate should be closely followed after discharge from the nursery. 相似文献993.
Tsung-Ming Tsao Ming-Jer Tsai Ya-Nan Wang Heng-Lun Lin Chang-Fu Wu Jing-Shiang Hwang Sandy-H.J. Hsu Hsing Chao Kai-Jen Chuang Charles- CK. Chou Ta-Chen Su 《PloS one》2014,9(7)
Background
Assessment of health effects of a forest environment is an important emerging area of public health and environmental sciences.Purpose
To demonstrate the long-term health effects of living in a forest environment on subclinical cardiovascular diseases (CVDs) and health-related quality of life (HRQOL) compared with that in an urban environment.Materials and Methods
This study included the detailed health examination and questionnaire assessment of 107 forest staff members (FSM) and 114 urban staff members (USM) to investigate the long-term health effects of a forest environment. Air quality monitoring between the forest and urban environments was compared. In addition, work-related factors and HRQOL were evaluated.Results
Levels of total cholesterol, low-density lipoprotein cholesterol, and fasting glucose in the USM group were significantly higher than those in the FSM group. Furthermore, a significantly higher intima-media thickness of the internal carotid artery was found in the USM group compared with that in the FSM group. Concentrations of air pollutants, such as NO, NO2, NOx, SO2, CO, PM2.5, and PM10 in the forest environment were significantly lower compared with those in the outdoor urban environment. Working hours were longer in the FSM group; however, the work stress evaluation as assessed by the job content questionnaire revealed no significant differences between FSM and USM. HRQOL evaluated by the World Health Organization Quality of Life-BREF questionnaire showed FSM had better HRQOL scores in the physical health domain.Conclusions
This study provides evidence of the potential beneficial effects of forest environments on CVDs and HRQOL. 相似文献994.
Brain and vascular cells form a functionally integrated signalling network that is known as the neurovascular unit (NVU). The signalling (autocrine, paracrine and juxtacrine) between different elements of this unit, especially in humans, is difficult to disentangle in vivo. Developing representative in vitro models is therefore essential to better understand the cellular interactions that govern the neurovascular environment. We here describe a novel approach to assay these cellular interactions by combining a human adult cerebral microvascular endothelial cell line (hCMEC/D3) with a fetal ganglionic eminence-derived neural stem cell (hNSC) line. These cell lines provide abundant homogeneous populations of cells to produce a consistently reproducible in vitro model of endothelial morphogenesis and the ensuing NVU. Vasculature-like structures (VLS) interspersed with patches of differentiating neural cells only occurred when hNSCs were seeded onto a differentiated endothelium. These VLS emerged within 3 days of coculture and by day 6 were stabilizing. After 7 days of coculture, neuronal differentiation of hNSCs was increased 3-fold, but had no significant effect on astrocyte or oligodendrocyte differentiation. ZO1, a marker of adherens and tight junctions, was highly expressed in both undifferentiated and differentiated endothelial cells, but the adherens junction markers CD31 and VE-cadherin were significantly reduced in coculture by approximately 20%. A basement membrane, consisting of laminin, vitronectin, and collagen I and IV, separated the VLS from neural patches. This simple assay can assist in elucidating the cellular and molecular signaling involved in the formation of VLS, as well as the enhancement of neuronal differentiation through endothelial signaling. 相似文献
995.
Kuan-Han Lee Yeh-Long Chen Bor-Ruey Huang Qing-Yu Zhu Ting-Chao Chou Cherng-Chyi Tzeng 《Nucleosides, nucleotides & nucleic acids》2013,32(6):1407-1416
Abstract A direct alkylation of trimethylsilylated pyrimidines and azapyrimidines with 1-azido-3-benzyloxy-2-chloromethoxypropane gave acyclic analogues of AZT in a good overall yield. None of the compounds exhibited significant antiviral activity against human immunodeficiency virus and herpes simplex virus. 相似文献
996.
Alexander A. Krayevsky Natalie B. Tarussova Qing-Yu Zhu Pedro Vidal Ting-Chao Chou Penny Baron 《Nucleosides, nucleotides & nucleic acids》2013,32(2-4):177-196
Abstract A number of nucleoside 5′-hydrogerphosphonates and nucleoside 5′-methylphosphonates were prepared, to study their ability to inhibit replication of HIV-1. Two compounds, the 5′-hydrogenphosphonate of 3′-azido-3′-deoxythymidine (AZT-HP, IVc) and of 3′-deoxy-3′-fluorothymidine (FLT-HP, IVa), exhibit potent anti-HIV-1 activity with selectivity indices similar to or better than those of their parent nucleosides. 相似文献
997.
Mao-Meng Tiao Chia-Wei Liou Li-Tung Huang Pei-Wen Wang Tsu-Kung Lin Jin-Bor Chen Yao-Min Chou Ying-Hsien Huang Hung-Yu Lin Chao-Long Chen Jiin-Haur Chuang 《PLoS genetics》2013,9(8)
Mitochondrial dysfunction has been implicated in the pathogenesis of biliary atresia (BA). This study aimed to determine whether a specific mitochondrial DNA haplogroup is implicated in the pathogenesis and prognosis of BA. We determined 40 mitochondrial single nucleotide polymorphisms in 15 major mitochondrial haplogroups by the use of 24-plex PCR and fluorescent beads combined with sequence-specific oligonucleotide probes in 71 patients with BA and in 200 controls in the Taiwanese population of ethnic Chinese background. The haplogroup B4 and E prevalence were significantly lower and higher respectively, in the patients with BA than in the controls (odds ratios, 0.82 [p = 0.007] and 7.36 [p = 0.032] respectively) in multivariate logistic-regression analysis. The 3-year survival rate with native liver was significantly lower in haplogroup E than the other haplogroups (P = 0.037). A cytoplasmic hybrid (cybrid) was obtained from human 143B osteosarcoma cells devoid of mtDNA (ρ0 cell) and was fused with specific mtDNA bearing E and B4 haplogroups donated by healthy Taiwanese subjects. Chenodeoxycholic acid treatment resulted in significantly lower free radical production, higher mitochondrial membrane potential, more viable cells, and fewer apoptotic cybrid B4 cells than parental 143B and cybrid E cells. Bile acid treatment resulted in a significantly greater protective mitochondrial reaction with significantly higher mitochondrial DNA copy number and mitofusin 1 and 2 concentrations in cybrid B4 and parental cells than in cybrid E cells. The results of the study suggested that the specific mitochondrial DNA haplogroups B4 and E were not only associated with lower and higher prevalence of BA respectively, in the study population, but also with differential susceptibility to hydrophobic bile acid in the cybrid harboring different haplogroups. 相似文献
998.
Kwang-Yu Chang Shan-Yin Tsai Shang-Hung Chen Hsiao-Hui Tsou Chia-Jui Yen Ko-Jiunn Liu Hsun-Lang Fang Hung-Chang Wu Bin-Fay Chuang Shao-Wen Chou Careen K Tang Shyun-Yeu Liu Pei-Jung Lu Ching-Yu Yen Jang-Yang Chang 《Journal of biomedical science》2013,20(1):43
Background
Dysregulated epidermal growth factor receptor (EGFR)-phosphoinositide-3-kinase (PI3K)-AKT signaling is considered pivotal for oral cancer, and the pathway is a potential candidate for therapeutic targeting.Results
A total of 108 archival samples which were from surgically resected oral cancer were examined. Immunohistochemical staining showed the protein expression of membranous wild-type EGFR and cytoplasmic phosphorylated AKT was detected in 63.9% and 86.9% of the specimens, respectively. In 49.1% of the samples, no phosphatase and tensin homolog (PTEN) expression was detected. With regard to the EGFR variant III (EGFRvIII), 75.0% of the samples showed positive expression for moderate to severe staining, 31.5% of which had high expression levels. Real-time polymerase chain reaction assays for gene copy number assessment of PIK3CA revealed that 24.8% of the samples had alterations, and of EGFR showed that 49.0% had amplification. Direct sequencing of PIK3CA gene showed 2.3% of the samples had a hotspot point mutation. Statistical assessment showed the expression of the EGFRvIII correlated with the T classification and TNM stage. The Kaplan-Meier analyses for patient survival showed that the individual status of phosphorylated AKT and EGFRvIII led to significant differences in survival outcome. The multivariate analysis indicated that phosphorylated AKT, EGFRvIII expression and disease stage were patient survival determinants.Conclusions
Aberrations in the EGFR-PI3K-AKT pathway were frequently found in oral cancers. EGFRvIII and phosphorylated AKT were predictors for the patient survival and clinical outcome. 相似文献999.
Srikanth Nagalla Jeff W Chou Mark C Willingham Jimmy Ruiz James P Vaughn Purnima Dubey Timothy L Lash Stephen J Hamilton-Dutoit Jonas Bergh Christos Sotiriou Michael A Black Lance D Miller 《Genome biology》2013,14(4):R34
Background
Gene expression signatures indicative of tumor proliferative capacity and tumor-immune cell interactions have emerged as principal biology-driven predictors of breast cancer outcomes. How these signatures relate to one another in biological and prognostic contexts remains to be clarified.Results
To investigate the relationship between proliferation and immune gene signatures, we analyzed an integrated dataset of 1,954 clinically annotated breast tumor expression profiles randomized into training and test sets to allow two-way discovery and validation of gene-survival associations. Hierarchical clustering revealed a large cluster of distant metastasis-free survival-associated genes with known immunological functions that further partitioned into three distinct immune metagenes likely reflecting B cells and/or plasma cells; T cells and natural killer cells; and monocytes and/or dendritic cells. A proliferation metagene allowed stratification of cases into proliferation tertiles. The prognostic strength of these metagenes was largely restricted to tumors within the highest proliferation tertile, though intrinsic subtype-specific differences were observed in the intermediate and low proliferation tertiles. In highly proliferative tumors, high tertile immune metagene expression equated with markedly reduced risk of metastasis whereas tumors with low tertile expression of any one of the three immune metagenes were associated with poor outcome despite higher expression of the other two metagenes.Conclusions
These findings suggest that a productive interplay among multiple immune cell types at the tumor site promotes long-term anti-metastatic immunity in a proliferation-dependent manner. The emergence of a subset of effective immune responders among highly proliferative tumors has novel prognostic ramifications. 相似文献1000.