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21.
Patterns of occurrence of dengue and chikungunya,and spatial distribution of mosquito vector Aedes albopictus in Swabi district,Pakistan
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Hui-Zhen Zhang Jin-Jian Wei Kannekanti Vijaya Kumar Syed Rasheed Cheng-He Zhou 《Medicinal chemistry research》2015,24(1):182-196
A series of novel d-glucose-derived 1,2,3-triazoles have been synthesized in excellent yields via Cu(I)-catalyzed 1,3-dipolar cycloaddition by using methyl α-d-glucopyranoside as starting material. All the new compounds were confirmed by 1H NMR, 13C NMR, IR, MS, and HRMS spectra, and their antimicrobial activities were screened against Gram-Positive, Gram-Negative bacteria, and fungi. Bioactive assay manifested that some of the synthesized glucose-derived 1,2,3-triazoles exhibited good antibacterial and antifungal activities. Notably, compound 5k gave the most potent efficiency with MIC50 value of 6 µM against Candida albicans, which was nine-fold more active than the reference drug Fluconazole. It also exhibited good antibacterial activity against Escherichia coli with the MIC50 value of 10.8 µM compared to Chloramphenicol while the corresponding hydrochloride 4k revealed remarkable inhibitory against Bacillus subtilis with an MIC50 value of 11 µM. 相似文献
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NK cells were characterized by their ability to spontaneously kill certain tumor and virus-infected cells. They constitute first line of defense against invading pathogens and usually become activated in viral infections particularly in early phases. Activated NK cells play a crucial role in the induction and amplification of virus-specific immunity by providing IFN-gamma and "danger signal". The functional activities of NK cells are regulated by a balance between the engagement of their inhibitory and activating receptors. In recent years, the discovery of several MHC and non-MHC binding NK receptors has provided important insights regarding NK cell biology and its role in viral infections. These receptors are increasingly being viewed as important regulators of immune response. Like many other viruses, HIV also seems to activate NK cells. However, several studies have reported compromised NK cell functions in HIV-infected individuals. The virus employs several strategies to counter the host's NK cell response, e.g., a differential downregulation of MHC class I molecules on the surface of infected cells, a dysregulated production of NK cell function-enhancing cytokines, direct inhibitory effects of certain viral proteins on NK cell functions, and changes in the expression of NK cell receptors, etc. The individuals expressing activating NK cell receptors and their cognate MHC ligands have activated NK cells. The development of AIDS is significantly delayed in these individuals after HIV infection. The discovery of NK receptors and their ligands has opened new avenues of developing AIDS vaccine and boosting innate and adaptive antiviral immunity in HIV-infected individuals. 相似文献
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Sharjeel Usmani Najeeb Ahmed Gopinath Gnanasegaran Rashid Rasheed Fahad Marafi Mashari Alnaaimi Mohammad Omar Ahmed Musbah Fareeda al Kandari Stijn De Schepper Tim Van den Wyngaert 《The British journal of radiology》2021,94(1120)
Objective:A new Bayesian penalized likelihood reconstruction algorithm for positron emission tomography (PET) (Q.Clear) is now in clinical use for fludeoxyglucose (FDG) PET/CT. However, experience with non-FDG tracers and in special patient populations is limited. This pilot study aims to compare Q.Clear to standard PET reconstructions for 18F sodium fluoride (18F-NaF) PET in obese patients.Methods:30 whole body 18F-NaF PET/CT scans (10 patients with BMI 30–40 Kg/m2 and 20 patients with BMI >40 Kg/m2) and a NEMA image quality phantom scans were analyzed using ordered subset expectation maximization (OSEM) and Q.Clear reconstructions methods with B400, 600, 800 and 1000. The images were assessed for overall image quality (IQ), noise level, background soft tissue, and lesion detectability, contrast recovery (CR), background variability (BV) and contrast-to-noise ratio (CNR) for both algorithms.Results:CNR for clinical cases was higher for Q.Clear than OSEM (p < 0.05). Mean CNR for OSEM was (21.62 ± 8.9), and for Q.Clear B400 (31.82 ± 14.6), B600 (35.54 ± 14.9), B800 (39.81 ± 16.1), and B1000 (40.9 ± 17.8). As the β value increased the CNR increased in all clinical cases. B600 was the preferred β value for reconstruction in obese patients. The phantom study showed Q.Clear reconstructions gave lower CR and lower BV than OSEM. The CNR for all spheres was significantly higher for Q.Clear (independent of β) than OSEM (p < 0.05), suggesting superiority of Q.Clear.Conclusion:This pilot clinical study shows that Q.Clear reconstruction algorithm improves overall IQ of 18F-NaF PET in obese patients. Our clinical and phantom measurement results demonstrate improved CNR and reduced BV when using Q.Clear. A β value of 600 is preferred for reconstructing 18F-NaF PET/CT with Q.Clear in obese patients.Advances in knowledge:18F-NaF PET/CT is less susceptible to artifacts induced by body habitus. Bayesian penalized likelihood reconstruction with18F-NaF PET improves overall IQ in obese patients. 相似文献
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Mohamed Abboud Nabil Al-Zaqri Taher Sahlabji Murad Eissa Ahmed T. Mubarak Radhouane Bel-Hadj-Tahar Ali Alsalme Fahad A. Alharthi Amjad Alsyahi Mohamed S. Hamdy 《RSC advances》2020,10(58):35407
Nickel(ii)dibenzotetramethyltetraaza[14]annulene complex (Nitmtaa) was synthetized and immobilized on post amino-functionalized SBA-15 (N-SBA-15) to obtain a stable and reusable nanocatalyst named as Nitmtaa@N-SBA-15. Here (3-aminopropyl)triethoxysilane (APTES) was first grafted on the surface SBA-15, then Nitmtaa was added and coordinated on the silica surface via APTES amine groups. The structure and morphology, and thermal stability of the prepared nanocatalyst was investigated using SEM, HR-TEM, BET, FT-IR, powder XRD, and TGA. HR-TEM and XRD results revealed a high dispersion of Nitmtaa on the SBA-15 surface. The catalytic activity of this nanocatalyst was evaluated in the epoxidation of styrene, under ambient conditions, using meta-chloroperoxybenzoic acid (m-CPBA) as the oxygen donor. This nanocatalyst showed an immediate and quantitative epoxidation of styrene with high turn-over-frequency ∼31.58 s−1. Moreover, the superior catalytic activity and high stability of Nitmtaa@N-SBA-15 could be maintained after four successive cycles. A possible reaction mechanism is also proposed.Immediate and quantitative epoxidation of styrene under ambient conditions catalyzed by new nanocatalyst obtained by immobilizing nickel(ii)dibenzotetramethyltetraaza[14]annulene in amino-functionalized SBA-15. 相似文献
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Jay W. Rhee Rory J. Petteys Amjad N. Anaizi Faheem A. Sandhu Jean-Marc Voyadzis 《European spine journal》2015,24(11):2546-2554
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