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Sung‐Hyun Hwang Myung‐Chul Kim Sumin Ji Yeseul Yang Yeji Jeong Yongbaek Kim 《Cancer science》2019,110(4):1256-1267
Metformin, a drug for type 2 diabetes mellitus, has shown therapeutic effects for various cancers. However, it had no beneficial effects on the survival rate of human malignant mesothelioma (HMM) patients. The present study was performed to elucidate the underlying mechanism of metformin resistance in HMM cells. Glucose‐starved HMM cells had enhanced resistance to metformin, demonstrated by decreased apoptosis and autophagy and increased cell survival. These cells showed abnormalities in mitochondria, such as decreased ATP synthesis, morphological elongation, altered mitochondrial permeability transition pore and hyperpolarization of mitochondrial membrane potential (MMP). Intriguingly, Mdr1 was significantly upregulated in mitochondria but not in cell membrane. The upregulated mitochondrial Mdr1 was reversed by treatment with carbonyl cyanide m‐chlorophenyl hydrazone, an MMP depolarization inducer. Furthermore, apoptosis and autophagy were increased in multidrug resistance protein 1 knockout HMM cells cultured under glucose starvation with metformin treatment. The data suggest that mitochondrial Mdr1 plays a critical role in the chemoresistance to metformin in HMM cells, which could be a potential target for improving its therapeutic efficacy. 相似文献
3.
Timo Rath Lukas Pfeifer Clemens Neufert reas Kremer Moritz Leppkes Arthur Hoffman Markus F Neurath Steffen Zopf 《World journal of gastroenterology : WJG》2020,26(16):1962-1970
BACKGROUND The adenoma detection rate(ADR) is inversely associated with the incidence of interval colorectal cancer and serves as a benchmark quality criterion during screening colonoscopy. However, adenoma miss rates reach up to 26% and studies have shown that a second inspection of the right colon in retroflected view(RFV) can increase ADR.AIM To assess whether inspection of the whole colon in RFV compared to standard forward view(SFV) can increase ADR.METHODS Patients presenting for screening or surveillance colonoscopy were invited to participate in this randomized controlled trial and randomized into two arms. In RFV arm colonoscopy was initially performed with SFV, followed by a second inspection of the whole colon in RFV. In the SFV arm first withdrawal was performed with SFV, followed by a second inspection of the whole colon again with SFV. Number, size and morphology of polyps found during first and second inspection in each colonic segment were recorded and all polyps were removed and sent for histopathology in separate containers.RESULTS Two hundred and five patients were randomly assigned to the RFV(n = 101) and SFV(n = 104) arm. In the RFV arm, both polyp detection rate(PDR) and ADR were increased under second inspection in RFV(PDR 1~(st) SFV: 39.8%, PDR 2~(nd)RFV: 46.6%; ADR 1~(st) SFV: 35.2%, ADR 2~(nd) RFV: 42%). Likewise, in the SFV arm,PDR and ADR were increased under second inspection(PDR 1~(st) SFV: 37.5%, PDR 2~(nd) SFV: 46.6%; ADR 1~(st) SFV: 34.1%, ADR 2~(nd)SFV: 44.3%) with no significant differences in ADR and PDR between the SFV and RFV arm. Mean number of adenomas per patient(APP) was increased in the RFV and SFV(APP RFV arm: 1~(st) SFV: 1.71; 2~(nd) RFV: 2.38; APP SFV arm: 1~(st) SFV: 1.83, 2~(nd)SFV:2.2). The majority of adenomas additionally found during second inspection in RFV or in SFV were located in the transverse and left-sided colon and were 5 mm in size.CONCLUSION Second inspection of the whole colon leads to increased adenoma detection with no differences between SFV and RFV. Hence, increased detection is most likely a feature of the second inspection itself but not of the inspection mode. 相似文献
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In this paper, we introduce a new type of troubled-cell indicator to improve
hybrid weighted essentially non-oscillatory (WENO) schemes for solving the hyperbolic conservation laws. The hybrid WENO schemes selectively adopt the high-order
linear upwind scheme or the WENO scheme to avoid the local characteristic decompositions and calculations of the nonlinear weights in smooth regions. Therefore,
they can reduce computational cost while maintaining non-oscillatory properties in
non-smooth regions. Reliable troubled-cell indicators are essential for efficient hybrid
WENO methods. Most of troubled-cell indicators require proper parameters to detect
discontinuities precisely, but it is very difficult to determine the parameters automatically. We develop a new troubled-cell indicator derived from the mean value theorem
that does not require any variable parameters. Additionally, we investigate the characteristics of indicator variable; one of the conserved properties or the entropy is considered as indicator variable. Detailed numerical tests for 1D and 2D Euler equations are
conducted to demonstrate the performance of the proposed indicator. The results with
the proposed troubled-cell indicator are in good agreement with pure WENO schemes.
Also the new indicator has advantages in the computational cost compared with the
other indicators. 相似文献
6.
Kun‐Yong Sung Seungkoo Lee Yeonjin Jeong Sang‐Yeul Lee 《The Australasian journal of dermatology》2021,62(1):60-63
A classic pilomatricoma, which usually presents with an asymptomatic, solitary, firm, subcutaneous nodule in the head, neck, or extremities of the paediatric population, is easily diagnosed based on its characteristic clinical and histopathological features. However, its variants often pose particular diagnostic challenges to clinicians due to their rarity and diverse clinicopathological features. We present a new pseudocystic variant, manifesting as solid lesions floating in a fluid‐filled sac. 相似文献
7.
Wai Man Mandy Chan Yik Weng Yew Thiam Seng Colin Theng Choon Fong Liew Hazel H Oon 《Singapore medical journal》2020,61(4):194
INTRODUCTIONPsoriasis is a chronic inflammatory condition that affects the skin and joints, and is associated with cardiovascular risk factors, including metabolic syndrome (MetS). We aimed to assess the prevalence of MetS in patients with psoriasis and determine whether there was a correlation between psoriasis severity and MetS in a Singapore population.METHODSThis was a cross-sectional study of patients with psoriasis, aged 18–69 years, who attended a tertiary dermatology referral centre in Singapore from October 2007 to February 2009. Fasting glucose, lipids, blood pressure, Psoriasis Area and Severity Index, and body mass index were measured. MetS was diagnosed in the presence of three or more criteria of the modified National Cholesterol Education Program Adult Treatment Panel III.RESULTSAmong 338 patients with psoriasis, there were 238 (70.4%) men and 100 (29.6%) women, who were Chinese (n = 228; 67.5%), Malay (n = 52; 15.4%) and Indian (n = 58; 17.2%). The prevalence of MetS was 45.1%. MetS was 44% more prevalent in patients older than 50 years (p = 0.02). Malay patients with psoriasis were significantly more likely to have hypertriglyceridaemia, elevated fasting plasma glucose and abdominal obesity. There was no significant correlation between psoriasis severity and risk of MetS.CONCLUSIONThe prevalence of MetS in patients with psoriasis in Singapore was 45.1%, or nearly threefold higher than the Singapore general population. Patients with psoriasis should be screened yearly for MetS and any modifiable cardiovascular risk factors should be actively controlled. 相似文献
8.
A mixed‐method study of effects of a therapeutic play intervention for children on parental anxiety and parents' perceptions of the intervention 下载免费PDF全文
9.
PNPLA3 gene polymorphism and response to lifestyle modification in patients with nonalcoholic fatty liver disease 下载免费PDF全文
10.
Yoo Min Han Su Jin Chung Seokha Yoo Jong In Yang Ji Min Choi Jooyoung Lee Joo Sung Kim 《World journal of gastroenterology : WJG》2022,28(8):853-867
BACKGROUND Helicobacter pylori(H.pylori)infection is known to prevent the occurrence of gastroesophageal reflux disease(GERD)by inducing gastric mucosal atrophy.However,little is known about the relationship between atrophic gastritis(AG)and GERD.AIM To confirm the inverse correlation between AG and the occurrence and severity of GERD.METHODS Individuals receiving health checkups who underwent upper gastrointestinal endoscopy at Seoul National University Healthcare System Gangnam Center were included.The grade of reflux esophagitis was evaluated according to the Los Angeles classification.Endoscopic AG(EAG)was categorized into six grades.Serologic AG(SAG)was defined as pepsinogen I≤70 ng/m L and pepsinogen I/II ratio≤3.0.The association between the extent of EAG and SAG and the occurrence and severity of GERD was evaluated using multivariate logistic regression analysis.RESULTS In total,4684 individuals with GERD were compared with 21901 healthy controls.In multivariate logistic regression analysis,advanced age,male sex,body mass index>23 kg/m2,presence of metabolic syndrome,current smoking,and alcohol consumption were associated with an increased risk of GERD.Seropositivity for H.pylori immunoglobulin G antibodies was associated with a decreased risk of GERD.There was an inverse correlation between the extent of EAG and occurrence of GERD:Odds ratio(OR),1.01[95%confidence interval(CI):0.90-1.14]in C1,0.87(0.78-0.97)in C2,0.71(0.62-0.80)in C3,0.52(0.44-0.61)in O1,0.37(0.29-0.48)in O2,and 0.28(0.18-0.43)in O3.Additionally,the extent of EAG showed an inverse correlation with the severity of GERD.The presence of SAG was correlated with a reduced risk of GERD(OR=0.49,95%CI:0.28-0.87,P=0.014).CONCLUSION The extent of EAG and SAG exhibited strong inverse relationships with the occurrence and severity of GERD.AG followed by H.pylori infection may be independently protect against GERD. 相似文献