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81.
Masahiko Kito Daichi Maeda Yukitsugu Kudo-Asabe Naoki Sato Ie-Ming Shih Tian-Li Wang Masamitsu Tanaka Yukihiro Terada Akiteru Goto 《PloS one》2016,11(6)
There is a growing body of evidence regarding cell competition between normal and mutant mammalian cells, which suggest that it may play a defensive role in the early phase of carcinogenesis. In vitro study in the past has shown that overexpression of vimentin in normal epithelial cells at the contact surface with transformed cells is essential for the cell competition involved in epithelial defense against cancer. In this study, we attempted to examine cell competition in human tissue in vivo by investigating surgically resected human fallopian tubes that contain p53 signatures and serous tubal intraepithelial lesions (STILs), a linear expansion of p53-immunopositive/TP53 mutant tubal epithelial cells that are considered as precursors of pelvic high grade serous carcinoma. Immunofluorescence double staining for p53 and the cell competition marker vimentin was performed in 21 sections of human fallopian tube tissue containing 17 p53 signatures and 4 STILs. The intensities of vimentin expression at the interface between p53-positive cells at the end of the p53 signature/STIL and adjacent p53-negative normal tubal epithelial cells were compared with the background tubal epithelium. As a result, the average vimentin intensity at the interfaces relative to the background intensity was 1.076 (95% CI, 0.9412 – 1.211 for p53 signature and 0.9790 (95% CI, 0.7206 – 1.237) for STIL. Thus, it can be concluded that overexpression of the cell competition marker vimentin are not observed in human tissue with TP53 alterations. 相似文献
82.
Chu-Chih Chen Shu-Li Wang Ming-Tsang Wu Yin-Han Wang Po-Chin Huang Bai-Hsiun Chen Chien-Wen Sun Chi-Kung Ho Yang-Chih Shih Ming-Neng Shiu Wen-Harn Pan Mei-Lien Chen Ching-Chang Lee Chao A. Hsiung 《PloS one》2016,11(3)
Background
In May 2011, di(2-ethylhexyl) phthalates (DEHP) and, to a lesser extent, di-iso-nonyl phthalate (DiNP) were found to have been illegally used for many years in Taiwan as clouding agents in foods including sports drinks, juice beverages, tea drinks, fruit jam/nectar/jelly, and health or nutrient supplements.Objective
To estimate the DEHP exposure for the study participants for the follow-up epidemiological study and health risk assessment.Methods
A total of 347 individuals possibly highly exposed to phthalate-tainted foods participated in the study. Exposure assessment was performed based on the participants'' responses to a structured questionnaire, self-report of exposure history, urinary metabolite concentrations, and DEHP concentration information in 2449 food records. A Bayesian statistical approach using Markov chain Monte Carlo simulation was employed to deal with the uncertainties in the DEHP concentrations of the contaminated foods and the participants'' likelihood of being exposed.Results
An estimated 37% and 15% of children younger than 12 years old were exposed to DEHP at medium (20–50 μg / kg_bw / day) and high AvDIs (50–100 μg / kg_bw / day), respectively, prior to the episode (9% and 3% in adults, respectively). Moreover, 11% of children and 1% of adults were highly exposed (> 100 μg / kg_bw / day), with a maximum of 414.1 μg / kg_bw / day and 126.4 μg / kg_bw / day, respectively.Conclusions
The phthalate exposure-associated adverse health effects for these participants warrant further investigation. The estimation procedure may be applied to other exposure assessment with various sources of uncertainties. 相似文献83.
Hsueh-Tzu Shih Wei-Yu Chen Kwei-Yan Liu Zong-Siou Shih Yi-Jyun Chen Paul-Chen Hsieh Kuan-Lin Kuo Kuo-How Huang Pang-Hung Hsu Ya-Wen Liu Shih-Peng Chan Hsiu-Hsiang Lee Yu-Chen Tsai June-Tai Wu 《PLoS genetics》2016,12(9)
To maintain a particular cell fate, a unique set of genes should be expressed while another set is repressed. One way to repress gene expression is through Polycomb group (PcG) proteins that compact chromatin into a silent configuration. In addition to cell fate maintenance, PcG proteins also maintain normal cell physiology, for example cell cycle. In the absence of PcG, ectopic activation of the PcG-repressed genes leads to developmental defects and malignant tumors. Little is known about the molecular nature of ectopic gene expression; especially what differentiates expression of a given gene in the orthotopic tissue (orthotopic expression) and the ectopic expression of the same gene due to PcG mutations. Here we present that ectopic gene expression in PcG mutant cells specifically requires dBRWD3, a negative regulator of HIRA/Yemanuclein (YEM)-mediated histone variant H3.3 deposition. dBRWD3 mutations suppress both the ectopic gene expression and aberrant tissue overgrowth in PcG mutants through a YEM-dependent mechanism. Our findings identified dBRWD3 as a critical regulator that is uniquely required for ectopic gene expression and aberrant tissue overgrowth caused by PcG mutations. 相似文献
84.
Chun Fu Lin Sanford P. C. Hsu Chung Jung Lin Wan Yuo Guo Chih Hsiang Liao Wei Fa Chu Sheng Che Hung Yang Shin Shih Yen Tzu Lin 《PloS one》2016,11(3)
Purpose
We sought to imitate angiographic cerebral circulation time (CCT) and create a similar index from baseline CT perfusion (CTP) to better predict vasospasm in patients with subarachnoid hemorrhage (SAH).Methods
Forty-one SAH patients with available DSA and CTP were retrospectively included. The vasospasm group was comprised of patients with deterioration in conscious functioning and newly developed luminal narrowing; remaining cases were classified as the control group. The angiography CCT (XA-CCT) was defined as the difference in TTP (time to peak) between the selected arterial ROIs and the superior sagittal sinus (SSS). Four arterial ROIs were selected to generate four corresponding XA-CCTs: the right and left anterior cerebral arteries (XA-CCTRA2 and XA-CCTLA2) and right- and left-middle cerebral arteries (XA-CCTRM2 and XA-CCTLM2). The CCTs from CTP (CT-CCT) were defined as the differences in TTP from the corresponding arterial ROIs and the SSS. Correlations of the different CCTs were calculated and diagnostic accuracy in predicting vasospasm was evaluated.Results
Intra-class correlations ranged from 0.96 to 0.98. The correlations of XA-CCTRA2, XA-CCTRM2, XA-CCTLA2, and XA-CCTLM2 with the corresponding CT-CCTs were 0.64, 0.65, 0.53, and 0.68, respectively. All CCTs were significantly prolonged in the vasospasm group (5.8–6.4 s) except for XA-CCTLA2. CT-CCTA2 of 5.62 was the optimal cut-off value for detecting vasospasm with a sensitivity of 84.2% and specificity 82.4%Conclusion
CT-CCTs can be used to interpret cerebral flow without deconvolution algorithms, and outperform both MTT and TTP in predicting vasospasm risk. This finding may help facilitate management of patients with SAH. 相似文献85.
Wen-Lin Liu Huei-Chuan Shih I-Szu Weng Ya-Zhu Ko Chi-Chu Tsai Chang-Hung Chou Yu-Chung Chiang 《PloS one》2016,11(4)
BackgroundThe intergeneric hybrids between Ascocenda John De Biase ‘Blue’ and Phalaenopsis Chih Shang''s Stripes have been generated to introduce the blue color into the Phalaenopsis germplasm in prior study. In order to confirm the inheritance in hybrid progenies, genomic in situ hybridization (GISH) and restriction fragment length polymorphism (RFLP) analysis were conducted to confirm the intergeneric hybridization status.Methods/ResultsGISH analysis showed the presence of both maternal and paternal chromosomes in the cells of the putative hybrids indicating that the putative hybrid seedlings were intergeneric hybrids of the two parents. Furthermore, twenty-seven putative hybrids were randomly selected for DNA analysis, and the external transcribed spacer (ETS) regions of nrDNA were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and RFLP analyses to identify the putative hybrids. RFLP analysis showed that the examined seedlings were intergeneric hybrids of the two parents. However, PCR-RFLP analysis showed bias to maternal genotype.ConclusionsBoth GISH and RFLP analyses are effective detection technology to identify the intergeneric hybridization status of putative hybrids. Furthermore, the use of PCR-RFLP analysis to identify the inheritance of putative hybrids should be carefully evaluated. 相似文献
86.
Objective
Given the shortage of cost-of-illness studies in dementia outside of the Western population, the current study estimated the annual cost of dementia in Taiwan and assessed whether different categories of care costs vary by severity using multiple disease-severity measures.Methods
This study included 231 dementia patient–caregiver dyads in a dementia clinic at a national university hospital in southern Taiwan. Three disease measures including cognitive, functional, and behavioral disturbances were obtained from patients based on medical history. A societal perspective was used to estimate the total costs of dementia according to three cost sub-categories. The association between dementia severity and cost of care was examined through bivariate and multivariate analyses.Results
Total costs of care for moderate dementia patient were 1.4 times the costs for mild dementia and doubled from mild to severe dementia among our community-dwelling dementia sample. Multivariate analysis indicated that functional declines had a greater impact on all cost outcomes as compared to behavioral disturbance, which showed no impact on any costs. Informal care costs accounted for the greatest share in total cost of care for both mild (42%) and severe (43%) dementia patients.Conclusions
Since the total costs of dementia increased with severity, providing care to delay disease progression, with a focus on maintaining patient physical function, may reduce the overall cost of dementia. The greater contribution of informal care to total costs as opposed to social care also suggests a need for more publicly-funded long-term care services to assist family caregivers of dementia patients in Taiwan. 相似文献87.
Yen‐Yu Lu Yao‐Chang Chen Yu‐Hsun Kao Yung‐Kuo Lin Yung‐Hsin Yeh Shih‐Ann Chen Yi‐Jen Chen 《Journal of cellular and molecular medicine》2016,20(6):1182-1190
Colchicine is a microtubule disruptor that reduces the occurrence of atrial fibrillation (AF) after an operation or ablation. However, knowledge of the effects of colchicine on atrial myocytes is limited. The aim of this study was to determine if colchicine can regulate calcium (Ca2+) homeostasis and attenuate the electrical effects of the extracellular matrix on atrial myocytes. Whole‐cell clamp, confocal microscopy with fluorescence, and western blotting were used to evaluate the action potential and ionic currents of HL‐1 cells treated with and without (control) colchicine (3 nM) for 24 hrs. Compared with control cells, colchicine‐treated HL‐1 cells had a longer action potential duration with smaller intracellular Ca2+ transients and sarcoplasmic reticulum (SR) Ca2+ content by 10% and 47%, respectively. Colchicine‐treated HL‐1 cells showed a smaller L‐type Ca2+ current, reverse mode sodium–calcium exchanger (NCX) current and transient outward potassium current than control cells, but had a similar ultra‐rapid activating outward potassium current and apamin‐sensitive small‐conductance Ca2+‐activated potassium current compared with control cells. Colchicine‐treated HL‐1 cells expressed less SERCA2a, total, Thr17‐phosphorylated phospholamban, Cav1.2, CaMKII, NCX, Kv1.4 and Kv1.5, but they expressed similar levels of the ryanodine receptor, Ser16‐phosphorylated phospholamban and Kv4.2. Colchicine attenuated the shortening of the collagen‐induced action potential duration in HL‐1 cells. These findings suggest that colchicine modulates the atrial electrical activity and Ca2+ regulation and attenuates the electrical effects of collagen, which may contribute to its anti‐AF activity. 相似文献
88.
89.
Shih‐Fan Chan Wei‐Kai Shih An‐Yu Chang Sheng‐Feng Shen I‐Ching Chen 《Ecology letters》2019,22(10):1668-1679
How abiotic and biotic factors constrain distribution limits at the harsh and benign edges of species ranges is hotly debated, partly because macroecological experiments testing the proximate causes of distribution limits are scarce. It has long been recognized – at least since Darwin’s On the Origin of Species – that a harsh climate strengthens competition and thus sets species range limits. Using thorough field manipulations along a large elevation gradient, we show the mechanisms by which temperature determines competition type, resulting in a transition from interference to exploitative competition from the lower to the upper elevation limits in burying beetles (Nicrophorus nepalensis). This transition is an example of Darwin’s classic hypothesis that benign climates favor direct competition for highly accessible resources while harsh climates result in competition through resources of high rivalry. We propose that identifying the properties of these key resources will provide a more predictive framework to understand the interplay between biotic and abiotic factors in determining geographic range limits. 相似文献
90.
Jyh‐Hong Lee Yuan‐Ta Shih Ming‐Liang Wei Chi‐Kuang Sun Bor‐Luen Chiang 《Journal of biophotonics》2019,12(5)
Atopic dermatitis (AD) is a cutaneous disease resulting from a defective barrier and dysregulated immune response. The severity scoring of atopic dermatitis (SCORAD) is used to classify AD. Noninvasive imaging approaches supplementary to SCORAD were investigated. Cr:forsterite laser‐based microscopy was employed to analyze endogenous third‐harmonic generation (THG) and second‐harmonic generation (SHG) signals from skin. Imaging parameters were compared between different AD severities. Three‐dimensional reconstruction of imaged skin layers was performed. Finally, statistic models from quantitative imaging parameters were developed for predicting disease severity. Our data demonstrate that THG signal intensity of lesional skin in AD were significantly increased and was positively correlated with AD severity. Characteristic gray level co‐occurrence matrix (GLCM) values were observed in more severe AD. In the 3D reconstruction video, individual dermal papilla and obvious fibrosis in the upper papillary dermis were easily identified. Our estimation models could predict the disease severity of AD patients with an accuracy of nearly 85%. The THG signal intensity and characteristic GLCM patterns are associated with AD severity and can serve as quantitative predictive parameters. Our imaging approach can be used to identify the histopathological changes of AD objectively, and to complement the SCORAD index, thus improving the accuracy of classifying AD severity. 相似文献