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81.
The activation of Ephrin (Eph) receptors, the largest tyrosine kinase families of cell surface receptor, has recently been addressed in human cholangiocarcinoma (CCA). Therefore, the present study aimed to investigate the role of Eph receptors and its ligands in CCA. Of all 50 cases of human CCA tested, immunohistochemical staining demonstrated that EphB2, EphB4, ephrinB1, and ephrinB2 were 100 % positive in CCA tissues with overexpressions of the above proteins as 56, 56, 70, and 48 % of cases, respectively. High expression of EphB2 was significantly correlated with the metastatic status of patients (P?=?0.027). We also found that the high co-expression level of EphB2/ephrinB1 or EphB2/ephrinB2 were significantly correlated with the metastatic status of the patients (P?=?0.034 and P?=?0.024). Furthermore, we showed that the high co-expression level of EphB4/MVD and ephrinB1/MVD were significantly correlated with the metastasis status of CCA patients (P?=?0.012 and P?=?0.029). We further demonstrated that the EphB2 suppression using siRNA significantly reduced CCA cell migration by decreasing the phosphorylation of focal adhesion kinase (FAK) and paxillin. In conclusion, the upregulation of EphB2 receptors and its specific ligands (ephrinB1 and ephrinB2) leads to CCA metastasis. Suppression of EphB2 expression as well as inhibition of its downstream signaling proteins might serve as possible therapeutic strategies in human CCA.  相似文献   
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SUMMARY

The survey was carried out to investigate the presence of potentially pathogenic free-living amoebae (FLA) during flood in Chiang Mai, Thailand in 2011. From different crisis flood areas, seven water samples were collected and tested for the presence of amoebae using culture and molecular methods. By monoxenic culture, FLA were detected from all samples at 37 °C incubation. The FLA growing at 37 °C were morphologically identified as Acanthamoeba spp., Naegleria spp. and some unidentified amoebae. Only three samples (42.8%), defined as thermotolerant FLA, continued to grow at 42 °C. By molecular methods, two non-thermotolerant FlA were shown to have 99% identity to Acanthamoeba sp. and 98% identity to Hartmannella vermiformis while the two thermotolerant FLA were identified as Echinamoeba exundans (100% identity) and Hartmannella sp. (99% identity). This first report of the occurrence of FLA in water during the flood disaster will provide information to the public to be aware of potentially pathogenic FLA.  相似文献   
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Phosphatidylinositol 3-kinase (PI3K) signaling plays a critical role in cholangiocarcinoma (CCA), as well as anti-cancer drug resistance and autophagy, the type II program cell death regulation. In this work, we aimed to: (1) determine the expression levels of several key components of PI3K signaling and (2) evaluate whether NVP-BEZ235, a novel dual PI3K/mTOR inhibitor, could inhibit CCA cell growth. Immunohistochemistry for p85α, p110α, AKT, p-AKT (T308), mTOR, p-mTOR (S2448), GSK-3β, p-GSK-3β (S9), PTEN, and p-PTEN (S380, T382/383) was performed in 30 CCA patients. Western blotting was used to analyze PTEN and p-PTEN expression in the cell lines (KKU-OCA17, KKU-100, KKU-M055, KKU-M139, KKU-M156, KKU-M213, and KKU-M214). The effects of NVP-BEZ235 on CCA cells were evaluated using a growth inhibition assay, flow cytometer and migration assay. Increased activation of PI3K/AKT signaling was reproducibly observed in the CCA tissues. The expression of p85α, mTOR, and GSK-3β was significantly correlated with metastasis. Interestingly, PTEN suppression by loss of expression or inactivation by phosphorylation was observed in the majority of patients. Furthermore, NVP-BEZ235 effectively inhibited CCA cell growth and migration through reduced AKT and mTOR phosphorylation and significantly induced G1 arrest without apoptosis induction, although increase autophagy response was observed. In conclusion, the constitutive activation of PI3K/AKT pathway in CCA is mainly due to PTEN inactivation by either loss of expression or phosphorylation along with an increased expression in its pathway components heralding a poor prognosis for CCA patients. This work also indicates that inhibition of PI3K and mTOR activity by the inhibitor NVP-BEZ235 has anti-cancer activity against CCA cells which might be further tested for CCA treatment.  相似文献   
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Objective

To investigate anti-infective treatments in HIV-infected surgical patients during the perioperative period.

Methods

A retrospective study of sepsis and surgical site infections (SSIs) was conducted in 266 HIV-infected patients. The patients were divided into 3 groups based on CD4+ T cells counts in the preoperative period: group A (0–199 cell/ul), group B (200–349 cell/ul) and group C ([greater than or equal to] 350 cell/ul). When the CD4 count was below 350 cells/uL, anti-retrovirus therapy was started. For patients whose preoperative CD4 counts were [less than or equal to] 200 cells/uL, preoperative antibiotic medication was started.

Results

Patients in group A were more likely to get sepsis than patients in the other two groups (p0.01). Among 82 patients with clean wounds, only one patient got SSIs. All patients with dirty wounds had acquired SSIs after surgery. There were only 6 patients dead at 30 days after surgery, a death rate of 2.3%. Sepsis appeared in 110 patients (41%).

Conclusions

Complete evaluation of surgical risk and suitable perioperative anti-infective treatment may lead to better outcome for HIV-infected surgical patients.  相似文献   
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Long-term outcome of idiopathic steroid-resistant nephrotic syndrome was retrospectively studied in 78 children in eight centers for the past 20 years. Median age at onset was 4.4 years (1.1–15.0 years) and the gender ratio was 1.4. Median follow-up period was 7.7 years (1.0–19.7 years). The disease in 45 patients (58%) was initially not steroid-responsive and in 33 (42%) it was later non-responsive. The main therapeutic strategies included administration of ciclosporine (CsA) alone (n = 29; 37%) and CsA + mycophenolate mofetil (n = 18; 23%). Actuarial patient survival rate after 15 years was 97%. Renal survival rate after 5 years, 10 years and 15 years was 75%, 58% and 53%, respectively. An age at onset of nephrotic syndrome (NS) > 10 years was the only independent predictor of end-stage renal disease (ESRD) in a multivariate analysis using a Cox regression model (P < 0.001). Twenty patients (26%) received transplants; ten showed recurrence of the NS: seven within 2 days, one within 2 weeks, and two within 3–5 months. Seven patients lost their grafts, four from recurrence. Owing to better management, kidney survival in idiopathic steroid-resistant nephrotic syndrome (SRNS) has improved during the past 20 years. Further prospective controlled trials will delineate the potential benefit of new immunosuppressive treatment.  相似文献   
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