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51.
Qing-Yi Lu Yu-Sheng Jin Allan Pantuck Zuo-Feng Zhang David Heber Arie Belldegrun Mai Brooks Robert Figlin Jianyu Rao 《Clinical cancer research》2005,11(4):1675-1683
Alteration of actin polymerization and loss of actin filaments is a marker of cellular dedifferentiation and early malignant transformation. To study this phenomenon, an in vitro human urothelial model consisting of two cell lines, HUC-PC and MC-T11, were incorporated into the study design. These two cell lines have different malignant transformation potential. The effect of green tea extract (GTE), a potential anticancer agent, on actin remodeling was investigated. Upon exposure to the carcinogen 4-aminobiphenyl (4-ABP), the untransformed HUC-PC undergoes malignant transformation whereas the transformed MC-T11 progresses from noninvasive to invasive tumor. GTE induces actin polymerization in MC-T11 cells in a dose-responsive manner, but this effect is less obvious in the untransformed, more differentiated HUC-PC cells, which natively have higher actin polymerization status. In contrast, GTE antagonizes carcinogen 4-ABP induced actin depolymerization and stress fiber disruption in HUC-PC cells. In MC-T11 cells, GTE inhibits 4-ABP induced motility by increasing cell adhesion and focal adhesion complex formation. The effect of GTE on actin remodeling seems to be mediated by the stimulation of small GTP-binding protein Rho activity, because C3 exoenzyme, a specific inhibitor for Rho, blocks GTE-mediated Rho activation and stress fiber formation in MC-T11 cells. This study shows that GTE exerts an effect on cytoskeletal actin remodeling and provides further support for the use of GTE as a chemopreventive agent. 相似文献
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目的:分析外周血游离Epstein-Barr病毒(EBV)是否特异地出现于鼻咽癌患者。方法:收集鼻咽癌患者和非鼻咽癌肿瘤患者血浆各50例,正常人血浆30例,提取DNA,荧光定量PCR检测EBV拷贝数,比较游离EBV在上述人群的差异。结果:在25例(50%)鼻咽癌患者血浆中检测到游离EBV,其拷贝数波动于1×103拷贝/ml血浆~2.6×106拷贝/ml血浆,中位数为5.3×105拷贝/ml血浆。在50例非鼻咽癌肿瘤患者和30例正常人血浆中均未检测到游离EBV。结论:游离EBV出现于鼻咽癌患者外周血,可能是一个较特异的鼻咽癌标志物。 相似文献
55.
CD10 down expression in follicular lymphoma correlates with gastrointestinal lesion involving the stomach and large intestine 下载免费PDF全文
Nobuhiko Ohnishi Katsuyoshi Takata Tomoko Miyata‐Takata Yasuharu Sato Akira Tari Yuka Gion Mai Noujima‐Harada Kohei Taniguchi Tetsuya Tabata Keina Nagakita Shizuma Omote Hiroyuki Takahata Masaya Iwamuro Hiroyuki Okada Yoshinobu Maeda Hiroyuki Yanai Tadashi Yoshino 《Cancer science》2016,107(11):1687-1695
Follicular lymphoma (FL) shows co‐expression of B‐cell lymphoma 2 (BCL2) and CD10, whereas downexpression of CD10 is occasionally experienced in gastrointestinal (GI) FL with unknown significance. Gastrointestinal FL is a rare variant of FL, and its similarity with mucosa‐associated lymphoid tissue lymphoma was reported. We investigated the clinicopathological and genetic features of CD10 downexpressed (CD10down) GI‐FL. The diagnosis of CD10down FL was carried out with a combination of pathological and molecular analyses. The incidence of CD10down GI‐FL was shown in 35/172 (20.3%) cases, which was more frequent than nodal FL (3.5%, P < 0.001). The difference was additionally significant between GI‐FL and nodal FL when the analysis was confined to primary GI‐FL (55.2% vs 3.5%, P < 0.001). Compared to CD10+ GI‐FL, CD10down GI‐FL significantly involved the stomach or large intestine (P = 0.015), and additionally showed the downexpression of BCL6 (P < 0.001). The follicular dendritic cell meshwork often showed a duodenal pattern in the CD10down group (P = 0.12). Furthermore, a lymphoepithelial lesion was observed in 5/12 (40%) gastric FL cases, which indicated caution in the differentiation of mucosa‐associated lymphoid tissue lymphoma. Molecular analyses were undertaken in seven cases of CD10down GI‐FL, and an identical clone was found between CD10down follicles and CD10+BCL2+ neoplastic follicles. In the diagnosis of cases with CD10down BCL2+ follicles, careful examination with molecular studies should be carried out. 相似文献
56.
Nam Quang Tran Steven D. Truong Phat Tung Ma Chi Khanh Hoang Bao Hoang Le Thang Tat Ngo Dinh Luong Van Tran Thang Viet Tran Linh Hoang Gia Le Khuong Thai Le Hien Thanh Nguyen Hoang Anh Vu Thao Phuong Mai Minh Duc Do 《Medicine》2022,101(46)
Type 2 diabetes mellitus (T2DM) is a genetically influenced disease, but few studies have been performed to investigate the genetic basis of T2DM in Vietnamese subjects. Thus, the potential associations of KCNJ11 and ABCC8 single nucleotide polymorphisms (SNPs) with T2DM were investigated in a Kinh Vietnamese population. A cross-sectional study consisting of 404 subjects including 202 T2DM cases and 202 non-T2DM controls was designed to examine the potential associations of 4 KCNJ11 and ABCC8 SNPs (rs5219, rs2285676, rs1799859, and rs757110) with T2DM. Genotypes were identified based on restriction fragment length polymorphism and tetra-primer amplification refractory mutation system polymerase chain reaction. After statistically adjusting for age, sex, and BMI, rs5219 was found to be associated with an increased risk of T2DM under 2 inheritance models: codominant (OR = 2.15, 95% confidence intervals [CI] = 1.09–4.22) and recessive (OR = 2.08, 95%CI = 1.09–3.94). On the other hand, rs2285676, rs1799859, and rs757110 were not associated with an increased risk of T2DM. Haplotype analysis elucidated a strong linkage disequilibrium between the 3 SNPs, rs5219, rs2285676, and rs757110. The haplotype rs5219(A)/rs2285676(T)/rs757110(G) was associated with an increased risk of T2DM (OR = 1.42, 95%CI = 1.01–1.99). The results show that rs5219 is a lead candidate SNP associated with an increased risk of developing T2DM in the Kinh Vietnamese population. Further functional characterization is needed to uncover the mechanism underlying the potential genotype-phenotype associations. 相似文献
57.
This work investigates an electrochemical impedance analysis based on synthesized TiO2 nanofibers (NFs) photoanodes, which were fabricated via electrospinning and calcination. The investigated photoanode substrate NFs were studied in terms of physicochemical tools to investigate their morphological character, crystallinity, and chemical contents via scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) analyses. As a result, the studied photoanode substrate NFs were applied to fabricate dye-sensitized solar cells (DSCs), and the electrochemical impedance analysis (EIS) was studied in terms of equivalent circuit fitting and impacts of N-doping, the latter of which was approved via XPS analysis. N-doping has a considerable role in the enhancement of charge transfers, which could be due to the strong interactions between active-site N atoms and the used photosensitizer. 相似文献
58.
May Ahmed Al-Masoud Mai M. Khalaf Mohamed Gouda Van-Duong Dao Ibrahim M. A. Mohamed Kamal Shalabi Hany M. Abd El-Lateef 《Materials》2022,15(21)
In this work, the preparation, characterization, and evaluation of a novel nanocomposite using polyaniline (PANi) functionalized bi-metal oxide ZnO-TiO2 (ZnTiO@PANi) as shielding film for carbon steel (CS)-alloy in acidic chloride solution at 298 K was studied. Different spectroscopic characterization techniques, such as UV-visible spectroscopy, dynamic light scattering (DLS), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR) approaches, as well as other physicochemical methods, such as X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), and field emission scanning electron microscope (FESEM), were used to describe the produced nanocomposites. The significance of these films lies in the ZnO-TiO2 nanoparticle’s functionalization by polyaniline, a material with high conductivity and electrochemical stability in acidic solutions. The mechanistic findings of the corrosion inhibition method were obtained by the use of electrochemical methods including open-circuit potentials (OCP) vs. time, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS). The results indicate that the synthesized ZnTiO@PANi is a powerful acidic corrosion inhibitor, and its inhibition effectiveness is 98.86% in the presence of 100 ppm. Additionally, the charge transfer resistance (Rp) value augmented from 51.8 to 432.7, and 963.7 Ω cm2 when the dose of PANi, and ZnTiO@PANi reached 100 ppm, respectively. The improvement in Rp and inhibition capacity values with an increase in nanocomposite dose is produced by the nanocomposite additives covering a larger portion of the surface, resulting in a decrease in alloy corrosion. By identifying the probable regions for molecule adsorption on the steel substrate, theoretical and computational studies provided significant details regarding the corrosion mitigation mechanism. The possibility of substituting old poisonous small substances with inexpensive and non-hazardous polymeric materials as shielding layers for utilization in the oilfield sectors is an important suggestion made by this research. 相似文献
59.
HoaLe Mai Sophie Deshayes ThiVanHa Nguyen Virginie Dehame AnneLaure Chn Sophie Brouard Christophe Blanquart 《Molecular oncology》2022,16(20):3606
Malignant pleural mesothelioma (MPM) is an aggressive cancer mainly related to asbestos exposure. Despite recent therapeutic advances, notably immunotherapies, the benefit remains limited and restricted to a small percentage of patients. Thus, a better understanding of the disease is needed to identify new therapeutic strategies. Recently, interleukin 7 receptor (IL‐7R) has been described as being expressed by MPM cells and associated with poorer patient survival. Thus, the aim of this work was to study the IL‐7R/IL‐7 pathway in MPM using patient samples. We found that, although more than 40% of MPM cells expressed IL‐7R, IL‐7 had no effect on their intracellular signaling. Accordingly, the addition of IL‐7 to the culture medium did not affect MPM cell growth. Using The Cancer Genome Atlas (TCGA) database, we showed that high IL7 gene expression in MPM tumors was associated with a higher overall patient survival and an induction of genes involved in the immune response. In pleural effusions (PEs), we found that IL‐7 concentration was not a good diagnostic biomarker. However, we observed that high IL‐7 levels in PEs were associated with shorter survival of MPM patients, but not of lung cancer patients. The prognostic value of IL‐7 was also conserved when only patients with epithelioid mesothelioma, the most common histological type of MPM, were analyzed. Taken together, our study suggests that, although the IL‐7R/IL‐7 signaling pathway is not functional in MPM cells, IL‐7 expression in PEs may have prognostic value in MPM patients. 相似文献
60.
Maya Takegami Yoshitaka Hashimoto Masahide Hamaguchi Ayumi Kaji Ryosuke Sakai Takuro Okamura Noriyuki Kitagawa Takafumi Osaka Hiroshi Okada Naoko Nakanishi Saori Majima Takafumi Senmaru Emi Ushigome Mai Asano Masahiro Yamazaki Michiaki Fukui 《Journal of Clinical Biochemistry and Nutrition》2022,71(2):136
This cross-sectional study investigated the association of metabolic syndrome (MetS) with sarcopenia defined by absolute low muscle mass (aLMM) and absolute low muscle strength (aLMS), or sarcopenia defined by relative low muscle mass (rLMM) and relative low muscle strength (rLMS). The cut-off values for men and women were as follows: aLMM, appendicular muscle mass in kg/height2 was <7.0 kg/m2 and <5.7 kg/m2; rLMM, appendicular muscle mass/body weight ×100 was <28.64% and <24.12%; aLMS, handgrip strength was <28 kg and <18 kg; and rLMS, handgrip strength/body weight ×100 was 51.26% and 35.38%. Among 207 men and 164 women, 41.5% men and 57.3% women had MetS, 14.0% men and 6.1% women had sarcopenia as defined by aLMM and aLMS, and 14.0% men and 22.0% women had sarcopenia defined by rLMM and rLMS. Compared with non-sarcopenia, adjusted OR of sarcopenia defined by aLMM and aLMS for the prevalence of MetS was 0.79 (95% CI 0.38–1.67), whereas that of sarcopenia defined by rLMM and rLMS for the prevalence of MetS was 20.6 (95% CI 7.81–54.3). Sarcopenia defined by rLMM and rLMS was associated with the risk of prevalence of MetS, whereas sarcopenia defined by aLMM and aLMS was not. 相似文献