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101.
102.
Novel sets of env gene PCR primers for distinguishing human immunodeficiency virus type 1 (HIV-1) subtypes B and E were designed. These primers anneal to different regions of the env gene and amplify DNA fragments of distinct sizes in a subtype-specific manner. Blood samples from 11 HIV-1 carriers in Thailand and 46 carriers in Japan were examined by PCR. The new env primers detected HIV-1 proviral DNA in 100% (11/11) and 88% (37/42) of the subtype B and E infection cases, respectively. The env primers also detected proviral DNA in saliva and breast milk samples in seven of 11 cases and two of three cases, respectively. The PCR subtyping results matched completely with those obtained by nucleotide sequencing of the env V3 region. The results suggest that the PCR using the env primers designed in this study may be an accurate and cost-effective method for differentiating subtypes B and E of HIV-1 in a large number of clinical samples. However, subtype E specific primer cross-react with subtype A, C, G, the new primer in this study is useful for regions in South East Asia where subtype E is predominant.  相似文献   
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104.
Background: Low levels of serum adiponectin are associated with increasedrisk and aggressiveness of obesity-related cancer. The purposeof the study reported here was to investigate the associationbetween serum adiponectin levels and clinicopathological parametersof renal cell carcinoma. Methods: Preoperative serum total and high-molecular-weight (HMW) adiponectinlevels were measured in 118 patients with renal cell carcinoma,and their association with clinicopathological parameters wasanalysed. Results: There were no statistically significant associations betweentotal adiponectin and HMW adiponectin and pathological stage,regional lymph node involvement, histological grade, histologicaltype (clear cell carcinoma versus other types) or presence ofvenous invasion. Total and HMW adiponectin levels in patientswith metastasis, however, were significantly lower than in patientswithout metastasis (P = 0.044 for total adiponectin and P =0.041 for HMW adiponectin). Low total and HMW adiponectin levelswere significantly associated with metastasis in patients witha normal BMI (<25 kg/m2) (P = 0.034 for total adiponectinand P = 0.028 for HMW adiponectin) but not in overweight andobese patients (P = 0.652 for total adiponectin and P = 0.489for HMW adiponectin). Multivariate logistic regression analysisshowed that total adiponectin level was an independent predictorof metastasis of renal cell carcinoma in all patients (P = 0.024,95% CI = 1.031–1.560) and in patients with a normal BMI(P = 0.040, 95% CI = 1.043–6.534). Conclusions: Serum total and HMW adiponectin levels were decreased in patientswith metastatic renal cell carcinoma. Adiponectin might be amolecular link between obesity and the progression of renalcell carcinoma.  相似文献   
105.

Objective

Emphysematous bullae (EB) are known to be associated with a high incidence of lung cancer; however, the reason for this has yet to be elucidated. The objective of the present study was to clarify the prevalence of programmed death-ligand-1 (PD-L1) expression in EB-associated lung adenocarcinomas.

Patients and Methods

A total of 369 patients with resected lung adenocarcinoma whose preoperative computed tomography findings were available for the examination of EB were analyzed for PD-L1 expression by immunohistochemistry and evaluated to determine the association between PD-L1 expression and EB-related adenocarcinomas.

Results

Among 369 patients, EB and cancer adjoining EB (Ca-ADJ) were identified in 81 (22.0%) and 50 (13.6%) patients, respectively. EB and Ca-ADJ were significantly associated with male gender, a smoking habit, a decreased forced expiratory volume in 1 second, a relatively higher tumor grade, advanced T status and stage, the presence of pleural and vessel invasion, invasive pathologic subtypes, and wild-type epidermal growth factor receptor. Seventy patients (19.0%) were positive for PD-L1 expression, whereas the remaining 299 patients (81.0%) were negative. Thirty-six (44.4%) and 29 (58.0%) of 81 and 50 patients with EB and Ca-ADJ, respectively, were positive for PD-L1 expression, which was shown to be significant by the Fisher exact test (P < .001 and P < .001, respectively). Among the 81 lung adenocarcinomas with EB, Ca-ADJ was significantly associated with PD-L1 expression (P = .021). In a multivariate analysis, the presence of Ca-ADJ was found to be an independent predictor of PD-L1 expression.

Conclusions

EB-associated lung adenocarcinomas express PD-L1 protein more frequently than those without EB.  相似文献   
106.

Purpose

To compare the inflammatory, coagulopathic, and fibrinolytic responses after endovascular aneurysm repair (EVAR) of an abdominal aortic aneurysm between two stent grafts. Fibrinogen degradation product (FDP) levels were compared between patients with or without an endoleak.

Materials and methods

EVAR was performed in 88 patients using an Excluder (37 patients) or a Zenith (51 patients). White blood cell count (WBC), C-reactive protein (CRP) levels, platelet count, and FDP levels were measured before and after EVAR.

Results

WBC and CRP increased and the platelet count decreased significantly on days 1 and 3 after EVAR in the Zenith group compared with the Excluder group. The change in FDP from baseline to 7 days after EVAR was ?1.99 ± 7.46 vs. 8.59 ± 9.38 μg/mL in patients with (n = 24) vs. without (n = 64) an endoleak (p < 0.001). A change in FDP of 3.1 μg/mL was the optimal cutoff point for predicting the presence of an endoleak (accuracy 0.762; sensitivity 0.875; specificity 0.717).

Conclusion

Inflammatory, coagulopathic, and fibrinolytic responses were greater in the Zenith group than in the Excluder group. A change in FDP of ≤3.1 μg/mL was predictive of an endoleak after EVAR.  相似文献   
107.
BACKGROUND: The role of complement in ischaemia-reperfusion injury has not been well investigated. 5I2 is a monoclonal antibody (mAb) directed against a rat membrane inhibitor of the C3 convertase step, which is the rat counterpart of mouse Crry/p65. 6D1 is a mAb against rat CD59 which inhibits the formation of membrane attack complexes. METHODS: We visualized the tissue distribution of these membrane inhibitors in rat gastrointestinal tract by immunohistochemical staining with the appropriate mAb. Then, we tested the hypothesis that complement regulatory proteins protect rat gastric mucosa against ischaemia-reperfusion stress by using these mAbs. Gastric mucosal integrity was continuously monitored by measuring the blood-to-lumen clearance of [51Cr]-labelled ethylenediaminetetraacetic acid (EDTA) under control conditions, during ischaemia and after reperfusion. RESULTS: Rat 6D1 and 5I2 antigens were both widely distributed and predominantly expressed on smooth muscle and endothelial cells in gastrointestinal tracts. Blockade of complement regulatory proteins with 5I2 and 6D1 mAbs resulted in a significant increase in [51Cr]-EDTA clearance after reperfusion. CONCLUSIONS: These findings support the hypothesis that endogenous complement regulatory proteins may act as important protective factors against ischaemia-reperfusion stress in rat gastric mucosa.  相似文献   
108.
109.
Titanium dioxide (TiO2) that had been irradiated with visible light (VL) was demonstrated to inactivate rotavirus, astrovirus, and feline calicivirus (FCV). The virus titers were dramatically reduced after exposure for 24 hrs to the VL-catalytic TiO2. The addition of bovine serum albumin could protect the virus against inactivation by VL-catalytic TiO2 in a dose-dependent manner. This finding implied that the VL-catalytic TiO2 products might somehow interact initially with the viral proteins in the process of virus inactivation. Moreover, we showed partial degradation of the rotaviral dsRNA genome. This was more prominent when the virus was exposed to the VL-catalytic TiO2 treatment for at least 2 days. An attempt was made to elucidate the mechanism underlying the inactivation of the viruses. It was found that upon activation of TiO2 with VL by using a white fluorescent lamp, the reactive oxygen species such as superoxide anions (O2-) and hydroxyl radicals (*OH) were generated in a significant amount after stimulation for 8, 16, and 24 hrs. We therefore assume that virus inactivation by VL-catalytic TiO2 might occur through the generation of O2- and *OH followed by damage to the viral protein and genome. This is the first report, to the best of our knowledge, demonstrating the inactivation of rotavirus, astrovirus and FCV by the presence of TiO2 film under VL as well as describing its mechanism.  相似文献   
110.
Previously, we reported that non-apoptotic cell death was induced in non-malignant mammary epithelial cells (HMECs) upon loss of anchorage during 48 h incubation in suspension. In this study, we examined HMECs in suspension at an earlier time point and found that most of them lost attachment ability to substrata when replated, although >80% were alive. This suggested that HMECs lost reattachment ability (RA) prior to cell death upon detachment. Concomitant with the loss of RA, a decrease in the levels of β1 and β4 integrin was observed. In sharp contrast, breast cancer cells retained integrin levels, reattached to substrata, and formed colonies after exposure to anchorage loss as efficiently as those maintained under adherent conditions. Such RA of cancer cells is essential for the metastatic process, especially for establishing adhesion contact with ECM in the secondary organ after systemic circulation. Further analysis suggested that sustained levels of β4 integrin, which was mediated by Rac1, was critical for RA after anchorage loss and lung metastasis of breast cancer cells. In the cancer cells, persistent Rac1 activity enhanced escape of β4 integrin from lysosomal degradation depending on actin-related protein 2/3 and TBC1D2, a GTPase-activating protein of Rab7 GTPase. Notably, simultaneous high expression of ITGB4 and RAC1 was associated with poor prognosis in patients with breast cancer. Therefore, β4 integrin and Rac1 are attractive therapeutic targets to eliminate RA in cancer cells, thereby preventing the initial step of colonization at the secondary organ during metastasis.  相似文献   
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