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81.
This study was undertaken to determine the effect of chronic exposure to sub-lethal concentrations of tannery effluent (TE) on the humoral antibody response and the cell-mediated immune response of the fish Cyprinous carpio. The LC50 value of the TE for C. carpio was determined by bioassay to be 3.8%. Sub-lethal concentrations of TE (0.6% and 0.3%) significantly suppressed the humoral and cell-mediated immune responses. Exposure of C. carpio to the TE had a significant effect on mean acceptance time (MAT) for transplanted scales. MAT was found to be 5–8 days for autografts and 4–7 days for allografts. The somatic indices of the kidney and spleen were reduced compared with controls.  相似文献   
82.
The application of 2-aryl/heteroarylidene-1H-indene-1,3(2H)-dione as an activated olefin source in the DABCO-catalyzed [3 + 2] cycloaddition with N-2,2,2-trifluoroethylisatin ketimines has been disclosed. This highly efficient 1,3-dipolar cycloaddition reaction offered a variety of trifluoro methyl group bearing spiro-pyrrolidine linked oxindoles with four consecutive stereocentres in good to excellent yield and excellent diastereoselectivity. The synthetic practicality of the protocol was established by demonstrating the enantioselective construction of spiro-pyrrolidine-oxindoles with two vicinal spiro-quaternary chiral centres in good yield excellent enantioselectivity (>90% ee) by using ultralow loading of quinine as the catalyst at room temperature.

A highly chemo- and regioselective construction of spiropyrrolidine oxindole is devised via DABCO catalysed [3 + 2] cycloaddition reaction.  相似文献   
83.
Purpose:To study the antifungal susceptibility of common corneal pathogenic fungi to antifungal agents in the North Indian population.Methods:Prospective study of the antifungal sensitivity testing (natamycin, amphotericin B, voriconazole, itraconazole, fluconazole, posaconazole, caspofungin, micafungin) of fungal isolates from 50 cases of culture positive fungal keratitis by using E test method. Details noted included demographic data, visual acuity, clinical details, grade of keratitis, healing time, and success in medical management.Results:Of 50 patients with fungal keratitis (mean age: 40.28 ± 16.77 years), 12 eyes healed within 3 weeks, 14 had a delayed healing response, and 24 had chronic keratitis. Among the 15 cases of Fusarium isolates, 93.3% were sensitive to natamycin, while 40% to amphotericin B; 66.6% to voriconazole, 13.4% to itraconazole and fluconazole each. 80% of Fusarium cases (n = 12) showed susceptibility to posaconazole. Among Aspergillus flavus isolates, 53.4% (n = 8) were sensitive to natamycin, with only 40% (n = 7) showing sensitivity to amphotericin B and good susceptibility to azoles. MIC against susceptible Fusarium spp. for natamycin was 3–16 µg/mL, amphotericin B: 1–8 µg/mL, voriconazole: 0.5–1.5 µg/mL, itraconazole: 0.5–12 µg/mL, posaconazole: 0.094–1.5 µg/mL. MIC against Aspergillus flavus was natamycin: 8–32 µg/mL, amphotericin B: 0.5–16 µg/mL, voriconazole: 0.025–4 µg/mL, itraconazole: 0.125–8 µg/mL, posaconazole: 0.047–0.25 µg/mL; against Aspergillus niger isolates, to natamycin was 6 µg/mL (n=1), amphotericin B 8–12 µg/mL (n = 3), voriconazole: 0.125–0.19 µg/mL (n = 3), itraconazole: 0.38–0.75 µg/mL, posaconazole: 0.064–0.19 µg/mL and against Aspergillus fumigatus (n = 1), was natamycin4 µg/mL, amphotericin B - 8 µg/mL, voriconazole 0.25 µg/mL, itraconazole 1 µg/mL, and posaconazole 0.19 µg/mL. MIC against susceptible Acremonium spp. for natamycin was 1.5–16 µg/mL, amphotericin B: 0.5–8 µg/mL, voriconazole: 0.19–3 µg/mL, itraconazole: 0.125 µg/mL, posaconazole: 0.125–0.5 µg/mL and against susceptible Curvularia was natamycin 0.75–4 µg/mL, amphotericin B 0.5–1 µg/mL, voriconazole 0.125–0.19 µg/mL, itraconazole 0.047–0.094 µg/mL, posaconazole 0.047–0.094 µg/mL. MIC against Mucor spp.+ Rhizopus spp. (n = 1) was natamycin: 8 µg/mL, amphotericin B: 0.75 µg/mL, posaconazole: 1.5 µg/mL. MIC against of Alternaria (n = 1) was voriconazole: 0.19 µg/mL, posaconazole: 0.094 µg/mL. MIC against Penicillium (n=1) was natamycin: 8 µg/mL, voriconazole: 0.25 µg/mL, itraconazole: 0.5 µg/mL, and Posaconazole: 0.125 µg/mL.Conclusion:Our observations highlight the variations in susceptibility to antifungal agents. Posaconazole seems to be effective with low MIC against common corneal pathogenic fungal isolates.  相似文献   
84.
Kala-Azar     
  相似文献   
85.
Polychlorinated biphenyls (PCBs) are global pollutants of major concern to human and animal reproductive health. The present study has examined the impact of Aroclor 1254 exposure on oxidative stress and testicular Leydig cell function. Adult albino male rats of the Wistar strain were dosed for 30 days with daily intraperitoneal injections of 2 mg/kg Aroclor 1254 or vehicle (corn oil). One day after the last treatment, animals were euthanized and blood collected for the assay of serum testosterone and estradiol. Testes were removed and Leydig cells were isolated for the assay of luteinizing hormone (LH) receptors, steroidogenic enzymes cytochrome P450 side chain cleavage enzyme (P450 scc), 3beta-hydroxysteroid dehydrogenase (3beta-HSD) and 17beta-hydroxysteroid dehydrogenase (17beta-HSD). Cellular antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), and glutathione-S-transferase (GST) were also assayed. Lipid peroxidation (LPO) and reactive oxygen species (ROS) were quantified. Results showed that Aroclor 1254 exposure lowered serum testosterone and estradiol levels. Leydig cell LH receptor density, activities of the steroidogenic enzymes P450 scc, 3beta-HSD, 17beta-HSD, antioxidant enzymes SOD, CAT, GPX, GR, and GST were significantly diminished whereas, LPO and ROS significantly elevated. Taken together, these results suggest that inefficient LH receptors, steroidogenic enzymes and antioxidant enzymes are possible mechanisms by which Aroclor 1254 treatment disrupts Leydig cell steroidogenesis.  相似文献   
86.
87.
Imaging of free radicals by electron paramagnetic resonance (EPR) spectroscopy using time domain acquisition as in nuclear magnetic resonance (NMR) has not been attempted because of the short spin-spin relaxation times, typically under 1 μs, of most biologically relevant paramagnetic species. Recent advances in radiofrequency (RF) electronics have enabled the generation of pulses of the order of 10–50 ns. Such short pulses provide adequate spectral coverage for EPR studies at 300 MHz resonant frequency. Acquisition of free induction decays (FID) of paramagnetic species possessing inhomogenously broadened narrow lines after pulsed excitation is feasible with an appropriate digitizer/averager. This report describes the use of time-domain RF EPR spectrometry and imaging for in vivo applications. FID responses were collected from a water-soluble, narrow line width spin probe within phantom samples in solution and also when infused intravenously in an anesthetized mouse. Using static magnetic field gradients and back-projection methods of image reconstruction, two-dimensional images of the spin-probe distribution were obtained in phantom samples as well as in a mouse. The resolution in the images was better than 0.7 mm and devoid of motional artifacts in the in vivo study. Results from this study suggest a potential use for pulsed RF EPR imaging (EPRI) for three-dimensional spatial and spectral-spatial imaging applications. In particular, pulsed EPRI may find use in in vivo studies to minimize motional artifacts from cardiac and lung motion that cause significant problems in frequency-domain spectral acquisition, such as in continuous wave (cw) EPR techniques.  相似文献   
88.
This paper presents a study on the uptake of norethynodrel and its binding to receptor proteins in the rat uterus and the human endometrium and myometrium cytoplasmic fractions. In the rat, 3H-norethynodrel was localized in vivo mainly in the 105,000 × g cytoplasmic fraction of the uterus, vagina, ovary, adrenal, pituitary and the hypothalamus. 3H-norethynodrel in the human and in the rat both in vivo and in vitro binds to uterine cytoplasmic proteins. The sedimentation coefficients of the rat uterine cytoplasmic norethynodrel binding proteins were 7.9S and 4.1S. The approximate molecular weights of the binding proteins were calculated to be 155,000 and 58,000. Norethynodrel binding proteins in the rat and human uterine cytosol were found to be thermolabile in nature. The experiments are suggestive of the presence of sulfhydryl groups in the receptor proteins. In competition studies using human myometrial cytosol, progesterone could displace norethynodrel from its binding sites. It is possible that the binding of norethynodrel to the uterine cytoplasmic proteins may be the primary mechanism of action of norethynodrel at the uterine level.  相似文献   
89.
90.
Nanotechnology is a multidisciplinary field and has achieved breakthroughs in bioengineering, molecular biology, diagnostics, and therapeutics. A recent advance in nanotechnology is the development of a functional nanosystem by incorporation, adsorption, or covalent coupling of polymers, carbohydrates, endogenous substances/ligands, peptides, proteins, nucleic acids, and polysaccharides to the surface of nanoparticles. Functionalization confers a wide array of interesting properties such as stealth characteristics, a bioadhesive property, and that it prevents aggregation of nanoparticles, imparts biostability and solubility, reduces toxicity, and provides site-specific delivery. This makes the nanosystem an intelligent tool for diagnostics, prognostics, and controlled and sustained delivery of protein, peptide, pDNA, and other therapeutic agents to specific targets (tissue, cell, and intracellular). Various types of functional nanosystems, such as carbon nanotubes, quantum dots, polymeric micelles, dendrimers, metallic nanoparticles, and liposomes, are being extensively explored. However, high tissue accumulation of nonbiodegradable nanoparticles has caused toxicity problems and rendered them as not-so-popular therapeutic and diagnostic systems. The toxicity and safety of nonbiodegradable nanoparticles are subject to future research. Polymeric nanoparticles have offered attractive alternative modules due to biocompatibility, nonimmunogenicity, nontoxicity, biodegradability, simple preparation methods, high physical stability, possibility of sustained drug release, and higher probability for surface functionalization. Depending on properties that have been modified, polymeric nanoparticles can be grouped in to four classes, namely, stealth, polysaccharide decorated biomimetic, bioadhesive, and ligand-anchored functional polymeric nanoparticles (f-PNPs). This review explores the ligand-anchored f-PNP as a carrier for active delivery of bioactives, envisaged to date. This review also details the ligands available for conjugation, their method of coupling to nanoparticles, and applications of f-PNPs in anticancer drug delivery, oral delivery, gene delivery, vaccine delivery, and intracellular delivery; site-specific delivery to liver, macrophages, lymphatics, and brain; and miscellaneous applications. This review also addresses formidable challenges encountered, and proposes some future strategies for development of a promising site-specific active delivery system.  相似文献   
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