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1.
Cancer stem cells (CSCs) play a decisive role in the development and progression of cancer. To investigate CSCs in Epstein‐Barr virus (EBV)‐associated carcinoma (EBVaGC), we screened previously reported stem cell markers of gastric cancer in EBV‐infected gastric cancer cell lines (TMK1 and NUGC3) and identified CD44v6v9 double positive cells as candidate CSCs. CD44v6/v9+/+ cells were sorted from EBVaGC cell line (SNU719) cells and EBV‐infected TMK1 cells and these cell populations showed high spheroid‐forming ability and tumor formation in SCID mice compared with the respective CD44v6/v9?/? cells. Sphere‐forming ability was dependent on the nuclear factor‐κB (NF‐κB) signaling pathway, which was confirmed by decrease of sphere formation ability under BAY 11‐7082. Small interfering RNA knockdown of latent membrane protein 2A (LMP2A), one of the latent gene products of EBV infection, decreased spheroid formation in SNU719 cells. Transfection of the LMP2A gene increased the sphere‐forming ability of TMK1 cells, which was mediated through NF‐κB signaling. Together, these results indicate that CD44v6v9+/+ cells are CSCs in EBVaGC that are maintained through the LMP2A/NF‐κB pathway. Future studies should investigate CD44v6/v9+/+ cells in normal and neoplastic gastric epithelium to prevent and treat this specific subtype of gastric cancer infected with EBV.  相似文献   
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BackgroundMalnutrition measured by the geriatric nutritional risk index (GNRI) was reported to be associated with poor prognosis for patients with peripheral artery disease (PAD). However, the optimal cut-off value of preprocedural GNRI for critical limb ischemia (CLI) and intermittent claudication (IC) is unknown. We aimed to determine its optimal cut-off value for CLI or IC patients requiring endovascular revascularization.MethodsWe explored data of 2246 patients (CLI: n = 1061, IC: n = 1185) registered in the Tokyo-taMA peripheral vascular intervention research COmraDE (TOMA-CODE) registry, which prospectively enrolled consecutive PAD patients who underwent endovascular revascularization in 34 hospitals in Japan from August 2014 to August 2016. The optimal cut-off values of GNRI were assessed by the survival classification and regression tree (CART) analyses, and the survival curve analyses for major adverse cardiovascular and limb events (MACLEs) were performed for these cut-off values.ResultsIn addition to the first cut-off value of 96.2 in CLI and 85.6 in IC, the survival CART provided an additional cut-off value of 78.2 in CLI and 106.0 in IC for further risk stratification. The survival curve was significantly stratified by the GNRI-based malnutrition status in both CLI [high risk: 47.7% (51/107), moderate: 30.1% (118/392), and low: 10.2% (53/520), log–rank p < 0.001] and IC [high risk: 14.3% (7/49), moderate: 4.5% (29/646), and low: 0.5% (2/407), log–rank p < 0.001]. The multivariate Cox-proportional hazard analysis showed that a higher GNRI was significantly associated with a better outcome in both CLI [hazard ratio (HR) per 1-point increase: 0.97, 95% CI: 0.96–0.98, p < 0.001] and IC (HR: 0.94, 95% CI: 0.91–0.97, p < 0.001).ConclusionsPreprocedural nutritional status significantly stratified future events in patients with PAD. Given that the optimal cut-off value of GNRI in CLI was almost 10-points lower than that of IC, using a disease-specific cut-off value is important for risk stratification.  相似文献   
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There is increasing evidence showing that clinicians employ different management strategies in their use of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC). In this meta-analysis, we investigated the differences in diagnosis frequency, resection rate (RR), and risk of malignancy (ROM) between Western (ie, American and European) and Asian cytopathology practices. We searched PubMed and Web of Science from January 2010 to January 2019. Proportion and 95% CIs were calculated using a random-effect model. We used independent sample t tests to compare frequencies, RR, and ROM between Western and Asian practices. We analyzed a total of 38 studies with 145,066 fine-needle aspirations. Compared with Asian practice, Western series had a significantly lower ROM in most of TBSRTC categories, whereas the RR was not statistically different. Focusing on indeterminate nodules, the RR in Western series was significantly higher (51.3% vs 37.6%; P = .048), whereas the ROM was significantly lower (25.4% vs 41.9%; P = .002) compared with those in Asian series. The addition of Asian cohorts increased ROM for most of diagnostic categories compared with the original TBSRTC. In conclusion, this study demonstrates a difference in Western and Asian thyroid cytology practice, especially regarding the indeterminate categories. Lower RR and higher ROM suggest that Asian clinicians adopt a more conservative approach, whereas immediate diagnostic surgery is favored in Western practice for indeterminate nodules. The addition of Asian series into a meta-analysis of TBSRTC altered ROM for several categories, which should be considered in future revisions of TBSRTC.  相似文献   
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Endothelial dysfunction is a hallmark of vasculopathy associated with systemic sclerosis (SSc). Reactive hyperemia peripheral arterial tonometry is a rapid and non-invasive technique to assess peripheral microvascular endothelial function by measuring changes in digital pulse volume during reactive hyperemia. Low scores of the reactive hyperemia index (RHI) imply an impaired vasodilatory response and, accordingly, impaired endothelial and vascular health. To investigate the clinical significance of the RHI in SSc patients, RHI values were measured in 43 SSc patients and 10 healthy controls. In diffuse cutaneous SSc (dcSSc) patients, RHI values were significantly decreased compared with healthy controls, and inversely correlated with disease duration. In total SSc patients, there was a significant inverse correlation between RHI values and skin score, and interstitial lung disease was associated with the decrease in RHI values. Among vascular symptoms, the current and past history of digital ulcers was seen more frequently in patients with decreased RHI values than in those with normal RHI values. Although no SSc patients had pulmonary arterial hypertension, an inverse correlation was evident between RHI values and mean pulmonary arterial pressure measured by right heart catheterization. These results indicate that the decrease in RHI values is associated with skin fibrosis, interstitial lung disease, digital ulcers and pulmonary vascular involvement leading to pulmonary arterial hypertension, supporting the canonical idea that endothelial dysfunction is a critical event underlying the development of tissue fibrosis and vascular complications in SSc.  相似文献   
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Background

There were few studies assessed the postoperative sarcopenia in patients with cancers. The objective of present study was to assess whether postoperative development of sarcopenia could predict a poor prognosis in patients with adenocarcinoma of esophagogastric junction, (AEG) and upper gastric cancer (UGC).

Methods

Patients with AEG and UGC who were judged as non-sarcopenic before surgery were reassessed the presence of postoperative development of sarcopenia 6 months after surgery. Patients were divided into the development group or non-development group, and clinicopathological factors and prognosis between these two groups were analyzed.

Results

The 5-year overall survival rates were significantly poorer in the development group than non-development group (68.0% vs. 92.6%, P?=?0.0118). Multivariate analyses showed that postoperative development of sarcopenia was an independent prognostic factor for poor overall survival (P?=?0.0237).

Conclusions

Postoperative development of sarcopenia was associated with a poor prognosis in patients with AEG and UGC.  相似文献   
7.
Hepatic arterial infusion (HAI) chemotherapy is expected to be a more effective and safer method to treat the hepatic metastasis of pancreatic cancer than intravenous (iv) administration because of higher tumor exposure and lower systemic exposure. To clarify the uptake mechanism of nucleoside anticancer drugs, including gemcitabine (GEM), in pancreatic cancer, we investigated the uptakes of radiolabeled uridine (a general substrate of nucleoside transporters) and GEM in pancreatic cancer cell lines MIA‐PaCa2 and As‐PC1. Uridine uptake was inhibited by non‐labeled GEM and also by S‐(4‐nitrobenzyl)‐6‐thioinosine (NBMPR; an inhibitor of equilibrative nucleoside transporters, ENTs) in a concentration‐dependent manner, suggesting that ENTs contribute to uridine uptake in pancreatic cancer cells. As for GEM, saturable uptake was mediated by high‐ and low‐affinity components with Km values of micromolar and millimolar orders, respectively. Uptake was inhibited in a concentration‐dependent manner by NBMPR and was sodium ion‐independent. Moreover, the concentration dependence of uptake in the presence of 0.1 μM NBMPR showed a single low‐affinity site. These results indicated that the high‐ and low‐affinity sites correspond to hENT1 and hENT2, respectively. The results indicated that at clinically relevant hepatic concentrations of GEM in GEM‐HAI therapy, the metastatic tumor exposure of GEM is predominantly determined by hENT2 under unsaturated conditions, suggesting that hENT2 expression in metastatic tumor would be a candidate biomarker for indicating anticancer therapy with GEM‐HAI.  相似文献   
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IgG4‐related disease (IgG4‐RD) can affect various organs, and the pancreas and salivary gland are representative examples. We report a rare case of IgG4‐RD of the paratestis. A 74‐year‐old man presented with left scrotal swelling. Scrotopuncture drainage and cytology confirmed a clear, yellow retention liquid (130 mL) with many small, similar lymphocytes and a few plasmacytes. Many lymphoid cells were immunopositive for CD3 on a cell block section, indicating that a predominant type of lymphoid cells was T cell. There were also some CD20 immunopositive cells and a few IgG4 immunopositive cells. Two months later the left scrotal swelling had returned, and he underwent radical inguinal orchiectomy. Microscopically, there was considerable lymphoplasmacytic inflammatory infiltration, fibrosis and abundant IgG4 immunopositive cells in the paratesticular region. The histopathologic and immunohistochemistry findings were consistent with IgG4‐RD. However, the abundant T cells in the scrotal fluid complicated the cytological diagnosis in our case.  相似文献   
10.
BACKGROUND: Genetic polymorphisms for cytokines and their receptors have been proposed as potential markers for periodontal disease. Tumor necrosis factor receptor 2 (TNFR2) is one of the cell surface receptors for TNF-alpha. Recent studies have suggested that TNFR2 gene polymorphism is involved in autoimmune and other diseases. OBJECTIVES: The aim of the present study is to evaluate whether TNFR2(+587T/G) gene polymorphism is associated with chronic periodontitis (CP). METHODS: One hundred and ninety-six unrelated subjects (age 40-65 years) with different levels of CP were identified according to established criteria, including measurements of probing pocket depth (PPD), clinical attachment level (CAL), and alveolar bone loss (BL). All subjects were of Japanese descent and non-smokers. Single nucleotide polymorphism at position +587(T/G) in the TNFR2 gene was detected by a polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) method. RESULTS: The frequency and the positivity of the +587G allele were significantly higher in severe CP patients than in controls (p=0.0097; odds ratio=2.61, p=0.0075; odds ratio=3.06). In addition, mean values of PPD, CAL, and BL were significantly higher in the +587G allele positive than in the negative subjects (p=0.035, 0.022, and 0.018, respectively). CONCLUSIONS: These findings suggest that the TNFR2(+587G) polymorphic allele could be associated with severe CP in Japanese.  相似文献   
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