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51.
Due to the long half-life of 137Cs (t1/2 ∼ 30 years), the selective extraction of cesium (Cs) from high level liquid waste is of paramount importance in the back end of the nuclear fuel cycle to avoid long term surveillance of high radiotoxic waste. As 1,3-di-octyloxycalix[4]arene-crown-6 (CC6) is suggested to be a promising candidate for selective Cs extraction, the improvement in the Cs extraction efficiency by CC6 has been investigated through the optimization of the effect of dielectric media on the extraction process. The effects of the feed acid (HNO3, HCl, and HClO4) and the composition of the diluents for the ligand in the organic phase on the extraction efficiency of Cs have been investigated systematically. In 100% n-octanol medium, Cs is found to form a 1 : 1 ion-pair complex with CC6 (0.03 M) providing a very high distribution ratio of DCs ∼ 22, suggesting n-octanol as the most suitable diluent for Cs extraction. No significant interference of other relevant cations such as Na, Mg and Sr was observed on the DCs value in the optimized solvent system. Density functional theory (DFT) based calculations have been carried out to elucidate the reason of ionic selectivity and enhanced Cs extraction efficiency of CC6 in the studied diluent systems. In addition to the ionic size-based selectivity of the crown-6 cavity, the polarity of the organic solvent system, the hydration energy of the ion, and the relative reorganization of CC6 upon complexation with Cs are understood to have roles in achieving the enhanced efficiency for the extraction of Cs by the CC6 extractant in nitrobenzene medium.

Separation scheme was developed for selective extraction of long-lived fission product 137Cs using substituted calix crown 6 ether from aqueous acidic solution.  相似文献   
52.
Invasive bacterial and fungal infections have notably increased the burden on the health care system and especially in immune compromised patients. These invasive bacterial and fungal species mimic and interact with the host extracellular matrix and increase the adhesion and internalization into the host system. Further, increased resistance of traditional antibiotics/antifungal drugs led to the demand for other therapeutics and preventive measures. Presently, metallic nanoparticles have wide applications in health care sectors. The present study has been designed to evaluate the advantage of Ag/Sn–SnO2 composite nanoparticles over the single oxide/metallic nanoparticles. By using in silico molecular docking approaches, herein we have evaluated the effects of Ag/Sn–SnO2 nanoparticles on adhesion and invasion responsible molecular targets such as LpfD (E. coli), Als3 (C. albicans) and on virulence/resistance causing PqsR (P. aeruginosa), RstA (Bmfr) (A. baumannii), FoxA (K. pneumonia), Hsp90 and Cyp51 (C. albicans). These Ag/Sn–SnO2 nanoparticles exhibited higher antimicrobial activities, especially against the C. albicans, which are the highest ever reported results. Further, Ag/Sn–SnO2 NPs exhibited interaction with the heme proionate residues such as Lys143, His468, Tyr132, Arg381, Phe105, Gly465, Gly464, Ile471 and Ile304 by forming hydrogen bonds with the Arg 381 residue of lanosterol 1 4α-demethylase and increased the inhibition of the Candida strains. Additionally, the Ag/Sn–SnO2 nanoparticles exhibited extraordinary inhibitory properties by targeting different proteins of bacteria and Candida species followed by several molecular pathways which indicated that it can be used to eliminate the resistance to traditional antibiotics.

Mesoporous Ag/Sn–SnO2 composite nanoparticles exhibits extraordinary inhibitory properties by targeting different proteins of bacteria and Candida species which can be used to eliminate the resistance of traditional antibiotics.  相似文献   
53.
Insulin inhibits platelet aggregation through nitric oxide synthesis by stimulating platelet insulin activated nitric oxide synthase. Impaired platelet insulin activated nitric oxide synthase in acute myocardial infarction (AMI) patients had been reported and thus our aim was to identify and isolate the factors impairing insulin activated nitric oxide in acute myocardial infarction patients’ plasma and study its effect on platelets aggregation in vitro. The insulin activated nitric oxide synthase inhibitor was identified as a protein and was purified from the plasma of AMI subjects using DEAE cellulose and Sephadex G-50 column, molecular weight determined by SDS-PAGE, nitric oxide quantified by methaemoglobin method, inhibitor protein quantified in plasma by immunoblot and ELISA, platelet aggregation studies done using an aggregometer, thromboxane-A2 in the platelets determined by radioimmunoassay, 125I-insulin radioligand binding studies done using normal subject platelets. The purified nitric oxide synthase inhibitor protein was ~66 kDa, concentration in AMI subjects’ plasma varied from 114 to 9,090 μM and was undetected in normal subjects’ plasma. The inhibitor protein competes with insulin for insulin receptor binding sites. The Incubation of the normal subject PRP with 5.0 μM inhibitor for 30 min followed by 0.4 μM ADP addition caused platelet aggregation in vitro, 130 μM aspirin or 400 μU insulin/ml addition was able to abrogate 0.4 μM ADP induced platelet aggregation even in the presence of 5.0 μM inhibitor. A potent inhibitory protein against insulin activated nitric oxide synthase in platelets appears in circulation of AMI subjects impairing nitric oxide production, potentiating ADP induced platelet aggregation and increasing the thromboxane-A2 level in platelets.  相似文献   
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PURPOSE: The purpose of this article is to describe a culturally competent, dietary self-management intervention designed to improve physiological outcomes, diabetes self-management, and costs of care for high-risk African Americans with type 2 diabetes. METHODS: A longitudinal, quasi-experimental design was used to evaluate the effectiveness of the intervention for 23 adult African Americans from a physician practice group in rural South Carolina. The intervention consisted of 4 low-fat dietary education classes, 6 discussion groups, and follow-up. Intervention sessions were provided by a dietitian and nurse case managers and framed as social events; families were encouraged to participate. RESULTS: Data suggest that the intervention significantly improved fat-related dietary habits, A1C values, fasting blood glucose, and frequency of acute care visits. A trend in reduction of lipids and weight also was observed. CONCLUSIONS: Culturally competent dietary self-management provides a meaningful approach to focused diabetes education for rural African Americans. Integrating nursing case management provides an innovative method of addressing the more global issues of delivery of care to underserved rural populations and decreasing the high costs of care.  相似文献   
57.
Pyriform sinus fistulae/sinuses are rare causes of recurrent cervical abscess, especially on the left side. They can also present as acute thyroiditis. Treatment in the form of simple incision and drainage is invariably unsuccessful, and the entity may be confused with the residual tract of a second branchial arch anomaly. We report a case of pyriform sinus fistula, and believe that this is only the second case report in India. We feel that greater awareness can lead to proper and appropriate diagnosis of this anomaly.  相似文献   
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Background

BCG vaccine is considered to have immunoprophylactic potential in leprosy. However controversy exists about the extent of prophylaxis it provides. In view of this, a study was undertaken to see the evolution of disease in established cases of leprosy who were already vaccinated with BCG and to compare it with the cases of leprosy who were not vaccinated with BCG.

Methods

114 newly diagnosed cases of leprosy were studied. Patients were divided into two groups-BCG vaccinated and non-vaccinated. Clinical diagnosis of leprosy was confirmed by bacteriological and histopathological studies in each case. All patients were given standard anti leprosy treatment and were evaluated monthly for a minimum period of one year.

Results

All the cases were males in the age group of 20 to 50 years. 25.4% of cases had received BCG vaccine and 74.6% were not vaccinated for the same. No significant difference was observed in the incidence of different types of leprosy in vaccinated and non-vaccinated groups. 25.9% cases in non-vaccinated group developed lepra reaction as compared to 13.8% in vaccinated group. The incidence of deformities and disabilities in vaccinated group was only 10.3% as against 18.8% in non-vaccinated group. The rate of bacillary clearance appeared faster in vaccinated group.

Conclusions

Although there is no significant difference in the pattern of different types of leprosy in BCG vaccinated and non-vaccinated cases, there is reduction in the incidence of reactions as well as deformities and disabilities in BCG vaccinated cases as compared to non-vaccinated cases.Key Words: BCG Vaccine, Leprosy  相似文献   
60.
Arterial involvement in Behçets disease is rare, occurring in various locations with multiple clinical expressions. When Behçets disease is associated with large arteries, lesions are usually in the form of aneurysms or occlusions. The simultaneous occurrence of these two lesions is even more unusual. We present a case of Behçets disease in which arterial involvement included an iliac artery thrombosis and an asymptomatic aneurysm of the infrarenal abdominal aorta. Behçets disease must be considered in the diagnosis of any unexplained inflammatory arteriopathy. Surgery is indicated for the majority of aneurysms and severe symptoms. The postoperative follow-up is based on noninvasive radiologic examinations.  相似文献   
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