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21.
The aim of the research was to evaluate the changes in the surface properties of five functional clothing materials with water-repellent finishes (including PFC-free finish) after 1, 5, and 10 washes with three detergents. A new approach to the interpretation of the water-repellent properties of textile materials is presented, based on two techniques, i.e., the spray test method and contact angle measurements. The results showed that washing materials with hydrophobic finishes can cause significant changes in their properties, which are mainly dependent on the composition and structure of the material, as well as the type of hydrophobic finish. The PFC-free finish is the least resistant to washing. For all materials with PFC finishes, the water repellency depends on the fluorine content on the surface and fabric topography. It was also found that increasing washing frequency resulted in a gradual decrease in water repellency. The loss of water repellency below an acceptable level (Grade 3) occurred after the fifth washing for all materials. Significant differences in the interpretation of the results of the spray test and contact angle measurements were observed. Using these methods separately provides information on the changes in the surface properties of the tested materials; however, their parallel application allows for obtaining complementary data, which is important for the proper interpretation of results. 相似文献
22.
Wolf Bat-Chen Tal Golan Irena Peri Zvi Ludmer Betty Schwartz 《Nutrition and cancer》2013,65(7):947-957
Allicin (diallyl thiosulfinate) is the best-known biologically active component in freshly crushed garlic extract. We developed a novel, simple method to isolate active allicin, which yielded a stable compound in aqueous solution amenable for use in in vitro and in vivo studies. We focused on the in vitro effects of allicin on cell proliferation of colon cancer cell lines HCT-116, LS174T, HT-29, and Caco-2 and assessed the underlying mechanisms. This allicin preparation exerted a time- and dose-dependent cytostatic effect on these cells at concentrations ranging from 6.2 to 310 μM. Treatment with allicin resulted in HCT-116 apoptotic cell death as demonstrated by enhanced hypodiploid DNA content, decreased levels of B-cell non-Hodgkin lymphoma-2 (Bcl-2), increased levels of bax and increased capability of releasing cytochrome c from mitochondria to the cytosol. Allicin also induced translocation of NF-E2-related factor-2 (Nrf2) to the nuclei of HCT-116 cells. Luciferase reporter gene assay showed that allicin induces Nrf2-mediated luciferase transactivation activity. SiRNA knock down of Nrf2 significantly affected the capacity of allicin to inhibit HCT-116 proliferation. These results suggest that Nrf2 mediates the allicin-induced apoptotic death of colon cancer cells. 相似文献
23.
Hui Yu Zhengming Chen Karla V. Ballman Mark A. Watson Ramaswamy Govindan Irena Lanc David G. Beer Raphael Bueno Lucian R. Chirieac Michael Herman Chui Guoan Chen Wilbur A. Franklin David R. Gandara Carlo Genova Kristine A. Brovsky Mary-Beth M. Joshi Daniel T. Merrick William G. Richards Fred R. Hirsch 《Journal of thoracic oncology》2019,14(1):25-36
Objectives
Anti–programmed cell death 1 (PD-1)/programmed death ligand 1 (PD-L1) immunotherapy has demonstrated success in the treatment of advanced NSCLC. Recently, PD-1/PD-L1 blockade also has demonstrated interesting results in small trials of neoadjuvant treatment in stage IB to IIIA NSCLC. In addition, several clinical trials using anti–PD-1/PD-L1 immunotherapy as an adjuvant or neoadjuvant treatment in patients with resectable stage NSCLC are ongoing. However, few analyses of anti–PD-1/PD-L1 immunotherapy–related biomarkers in early-stage squamous cell lung carcinoma (SqCLC) have been reported. In this study, we evaluated PD-L1 protein expression, tumor mutation burden, and expression of an immune gene signature in early-stage SqCLC, providing data for identifying the potential role for patients with anti–PD-1/PD-L1 treatment in early-stage SqCLC.Methods
A total of 255 specimens from patients with early-stage SqCLC were identified within participating centers of the Strategic Partnering to Evaluate Cancer Signatures program. PD-L1 protein expression by immunohistochemistry was evaluated by using the Dako PD-L1 22C3 pharmDx kit on the Dako Link 48 auto-stainer (Dako, Carpinteria, CA). Tumor mutation burden (TMB) was calculated on the basis of data from targeted genome sequencing. The T-effector and interferon gamma (IFN-γ) gene signature was determined from Affymetrix gene chip data (Affymetrix, Santa Clara, CA) from frozen specimens.Results
The prevalence of PD-L1 expression was 9.8% at a tumor proportion score cutoff of at least 50%. PD-L1 mRNA and programmed cell death 1 ligand 2 mRNA positively correlated with PD-L1 protein expression on tumor cells (TCs) and tumor-infiltrating immune cells. PD-L1 protein expression on tumor-infiltrating immune cells was correlated with the T-effector and IFN-γ gene signature (p < 0.001), but not with TMB. For TCs, all of these biomarkers were independent of each other and neither PD-L1 protein expression, TMB, or T-effector and IFN-γ gene signatures were independently prognostic for patient outcomes.Conclusions
Evaluation of PD-L1 expression, TMB, and T-effector and IFN-γ gene signatures in the cohort with early-stage SqCLC found them to be independent of each other, and none was associated with overall survival. Our results also support the hypothesis that PD-L1 expression is regulated by an intrinsic mechanism on TCs and an adaptive mechanism on immune cells. 相似文献24.
Martin H Ellis Ruth Hadari Noa Tchuvrero Shirley Shapira Irena Kovlenko Mariana Kozmiakova Rivka Zissin Avishay Elis 《Clinical and applied thrombosis/hemostasis》2006,12(2):199-204
Low molecular weight heparins (LMWHs) are a rapidly growing class of anticoagulant drug. Their efficacy has been demonstrated in several clinical settings where they are rapidly becoming the anticoagulant of choice. Controlled clinical studies in patients with deep vein thrombosis, pulmonary embolism, and unstable angina have documented that the frequency of major hemorrhage is 0.5-4%. The purpose of the study was to determine the frequency of minor and major hemorrhage occurring in patients receiving anticoagulant doses of an LMWH (enoxaparin) during routine clinical practice. A prospective, observational study of consecutive patients receiving enoxaparin 1 mg/kg twice daily for at least 24 hours in five internal medicine wards of a university teaching hospital was performed. Five hundred forty-nine patients were studied. The mean age was 67.5+/-15.5 years and the mean duration of enoxaparin therapy was 3.8+/-1.5 days. Hemorrhage was documented in a total of 94 patients (17.3%). Major hemorrhage occurred in 14 patients (2.6%), injection-site hemorrhage occurred in 55 patients (10%), and minor hemorrhage (noninjection site) was documented in 25 patients (4.7%). There were two deaths attributed to hemorrhage. Patients with major hemorrhage were older than patients with minor or no hemorrhage (75.5+/-10.4 versus 66.8+/-15.2 years; p=0.03) and occurred in patients receiving enoxaparin for a longer period (5.14+/-3.8 days) than those with minor (4+/-2.5 days) or no hemorrhage (2.9+/-2.1 days). Major hemorrhage was significantly associated with impaired renal function, chronic liver disease, and concomitant treatment with warfarin or a proton pump inhibitor. Enoxaparin used in anticoagulant doses in unselected medical patients is not associated with more major hemorrhagic complications than observed in controlled clinical trials. Major hemorrhage may be more likely in older patients, in patients with chronic liver disease and impaired renal function, in patients receiving prolonged enoxaparin therapy, and in patients receiving warfarin or proton pump inhibitors. 相似文献
25.
The epidemiology of social isolation and loneliness among older adults during the last years of life
26.
Zihni Sulaj Alert Drishti Irena ?eko Amarda Gashi Gentian Vyshka 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2015,23(1)
Background
Acute poisonings particularly through pesticides have become a major public health concern in Albania during the last decade.Findings
The number of fatalities due to aluminum phosphide intoxications was more than doubled during a five year-period from 2009 to 2013, and a cluster of suicides perpetrated with Phostoxin was registered. Several factors are accountable for such a phenomenon, including the fact that aluminum phosphide agents are freely available in the Albanian market, their price is extremely low and they are sold without any legal restriction. The mass media unfortunately warranted an emulating effect to dramatic intoxications, which gained by such means the notoriety of a secure lethal weapon.Conclusions
Our experience with more than three hundred intoxications with aluminum phosphide agents in the last five years, showed that a considerable delay from the moment of exposure (mainly through ingestion) to specialized medical help seeking, created a considerable obstacle for a successful treatment of cases, and eventually for the survival of patients. The lack of a specific antidote adds further challenges to all these exposures. The need for public health policies aiming at prevention, awareness, and possibly the substitution of Phostoxin or other aluminum phosphide pesticides with less dangerous agents is formulated. 相似文献27.
Infliximab, a chimeric antibody to tumour necrosis factor-alpha (TNF-alpha), holds much promise for the treatment of patients with Crohn's disease. On the cellular level, infliximab affects survival and, as presented by Agnholt et al. in this issue of the journal, inhibits GM-CSF (granulocyte-macrophage colony-stimulating factor) production by intestinal T lymphocytes. Future studies will reveal whether the pro-apoptotic effect of infliximab is linked to its inhibition of endogenous GM-CSF expression in T cells. Treatment of Crohn's disease, a severe chronic intestinal disorder, may at times be challenging as it can be refractory to routine therapy. Among novel therapeutic strategies, agents that neutralize tumour necrosis factor-alpha (TNF-alpha) are of particular interest because of the crucial role of TNF-alpha in sustaining chronic mucosal inflammation. The exact mechanism of the anti-TNF action, apart from direct activity that neutralizes cytokines, is not fully understood. Cellular effects of TNF-alpha neutralizing treatment include an increased susceptibility to apoptosis of intestinal mucosal T cells. A novel pathway of anti-TNF-alpha interaction with T cells has been presented in the current issue of this journal. Agnholt et al. have found that in-vivo or in-vitro administration of infliximab, a chimeric antibody to TNF-alpha, resulted in a decreased production of GM-CSF (granulocyte-macrophage colony-stimulating factor) by T cells. Infliximab related down-regulation of TNF-alpha induced GM-CSF expression may be one of the mechanisms by which this drug increases the rate of apoptosis in T cells. 相似文献
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