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41.
Leishmania infantum is a causative agent of endemic zoonotic visceral leishmaniasis (VL) in regions of South America and the Mediterranean. Dogs are the major reservoirs for L. infantum in these regions, and control of disease in dogs could have a significant impact on human disease. Although dogs share many symptoms of VL with humans as a result of L. infantum infection, they also show some unique clinical manifestations, which are often a combination of visceral and cutaneous leishmaniasis, suggesting different mechanisms of disease development in dogs and humans. Here, we compare antibody responses of dogs and humans with VL to various defined leishmanial antigens. Parasite lysate and K39, the two most commonly used antigens for serodiagnosis of VL, detected the highest levels of antibodies in both humans and dogs with VL, whereas the recognition patterns of these antigens were distinct between the hosts. Among other defined antigens tested, LmSTI1 and CPB detected higher levels of antibodies in dogs and humans, respectively. These results indicate there is a difference between humans and dogs in antigen recognition patterns during VL. We infer that different strategies may need to be used in development of vaccines and diagnostics for humans and for dogs. In addition, we show a correlation between antibody titers to several antigens and severity of clinical symptoms during canine VL.  相似文献   
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The 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay of the ether, methanol, and aqueous extracts of the spice Myristica malabarica (rampatri) revealed the methanol extract to possess the best antioxidant activity. Column chromatography of the methanol extract led to the isolation of a new 2-acylresorcinol and four known diarylnonanoids of which the diarylnonanoid, malabaricone C, showed the maximum DPPH scavenging activity. Malabaricone C could prevent both Fe(II)- and 2,2'-azobis(2-amidinopropane)dihydrochloride-induced lipid peroxidation (LPO) of rat liver mitochondria more efficiently than curcumin. The anti-LPO activity of malabaricone C was attributed to its better radical scavenging and Fe(II) chelation capacities. The superior activity of malabaricone C was rationalized by a systematic structure-activity correlation of the results obtained with the structurally related diarylnonanoids and curcumin. Malabaricone C also prevented the gamma-ray-induced damage of pBR322 plasmid DNA in a concentration-dependent manner. The radioprotective activity was found to correlate with its (*)OH radical scavenging property, which matched well with that of d-mannitol.  相似文献   
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Genetic Resources and Crop Evolution - Indian mustard [Brassica juncea (L.) Czern.] is a major edible oil crop of India. The Indian Council of Agricultural Research—National Bureau of Plant...  相似文献   
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ABSTRACT

Cellulose nanocrystals have emerged as replacements for man-made fibers to fabricate environmentally friendly green products. In this work, cellulose nanocrystals (CNCs) of mixed morphology were synthesized by acid hydrolysis of compost using sulfuric acid. Compost, an agro-based biomass feedstock, procured from water hyacinth (Eichhornia crassipes), cow dung, and saw dust (8:1:1) was utilized for the extraction of cellulose, followed by synthesis of CNCs. Compost was prepared using a rotary drum composter and was utilized for the production of CNCs. A two-step procedure for the extraction of CNCs was studied. Initial chemical treatments, including alkali treatment and bleaching, led to the gradual removal of lignin and hemicellulose, while the subsequent sulphuric acid (40%) hydrolysis step yields CNCs in an aqueous suspension. The synthesized CNCs have been studied by Fourier transform infrared (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and particle size analyzer. The morphology and dimension of nanofibrils were studied by scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM) techniques, which showed mixed morphology of rectangular cone type and spherical dimensions. Fabrication of such mixed morphology was found to be dependent on the selected biomass. The trace of metal elements present in the biomass was investigated by scanning electron microscopy-energy dispersive X-ray (SEM-EDX). We report a cost effective and feasible approach of utilizing inexpensive bioresources for production of value added products like CNCs, which could find potential application in the fields of healthcare, biomedical engineering, packaging, etc.  相似文献   
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A 6-year-old Canadian Warmblood gelding was presented for suspicion of keratoma growth, based on a history of recurring abscesses in the right front foot. Radiographic examination and computed tomography identified 2 bilaterally symmetrical, laminar epidermal ingrowths adhered to the hoof wall at the level of the lateral and medial heels.  相似文献   
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Objective Mitomycin C (MMC) is used clinically to treat corneal scarring in human patients. We investigated the safety and efficacy of MMC to treat corneal scarring in horses by examining its effects at the early and late stages of disease using an in vitro model. Procedure An in vitro model of equine corneal fibroblast (ECF) developed was used. The ECF or myofibroblast cultures were produced by growing primary ECF in the presence or absence of transforming growth factor beta‐1 (TGFβ1) under serum‐free conditions. The MMC dose for the equine cornea was defined with dose‐dependent trypan blue exclusion and (3‐4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assays after applying MMC to the cultures once for 2 min. The efficacy of MMC to control corneal scarring in horses was determined by measuring mRNA and protein expression of corneal scarring markers (alpha‐smooth muscle actin and F‐actin) with western blotting, immunocytochemistry and/or quantitative real‐time polymerase chain reactions. Results A single 2‐min treatment of 0.02% or less MMC did not alter ECF phenotype, viability, or cellular proliferation whereas 0.05% or higher MMC doses showed mild‐to‐moderate cellular toxicity. The TGFβ1 at 1 ng/mL showed significant myofibroblast formation in ECF under serum‐free conditions. A single 2‐min, 0.02% MMC treatment 24 h (early) after TGFβ1 stimulation significantly reduced conversion of ECF to myofibroblasts, however, a single 0.02% MMC treatment 11 days after TGFβ1 stimulation showed moderate myofibroblast inhibition. Conclusions That MMC safely and effectively reduced scarring in ECF by reducing the degree of transdifferentiation of corneal fibroblasts to myofibroblasts in vitro. Further clinical in vivo investigations are warranted using MMC in horses.  相似文献   
49.
Objective To determine if hybrid adeno‐associated virus serotype 2/5 (AAV5) vector can effectively deliver foreign genes into the equine cornea without causing adverse side effects. The aims of this study were to: (i) evaluate efficacy of AAV5 to deliver therapeutic genes into equine corneal fibroblasts (ECFs) using enhanced green fluorescent protein (EGFP) marker gene, and (ii) establish the safety of AAV5 vector for equine corneal gene therapy. Material Primary ECF cultures were harvested from healthy donor equine corneas. Cultures were maintained at 37°C in humidified atmosphere with 5% CO2. Procedure AAV5 vector expressing EGFP under control of hybrid cytomegalovirus + chicken β‐actin promoter was applied topically to ECF. Expression of delivered EGFP gene in ECF was quantified using fluorescent microscopy. Using fluorescent staining, the total number of cells and transduction efficiency of tested AAV vector was determined. Phase contrast microscopy, trypan blue and TUNEL assays were used to determine toxicity and safety of AAV5 for ECFs. Results Topical AAV5 application successfully transduced significant numbers of ECFs. Transduction efficiency was 13.1%. Tested AAV5 vector did not cause phenotype change or significant cell death and cell viability was maintained. Conclusions Tested AAV5 vector is effective and safe for gene therapy in ECFs in vitro.  相似文献   
50.
Sequence characterized amplified region (SCAR) markers that are highly desirable in crop breeding for marker‐assisted selection (MAS) are routinely analysed by gel‐based methods that are low‐throughput, time‐consuming and laborious. In this study, we showed a rapid and convenient method for analysis of SCAR markers in a gel‐free manner. Seven SCAR markers, linked to rust resistance genes (Sr24, Sr26 and Sr31) and seed quality traits (Pina, Pinb and Glu‐D1) in wheat (Triticum aestivum), were amplified on a real‐time PCR machine using custom reaction mixture. Subsequently, melting curve analysis was performed, to assess the specificity of amplicons. Using the amplicon‐specific melt‐profiles, the presence/absence of SCAR markers was analysed in fifteen genotypes and five F2 populations. Unlike the fluorescence‐based in‐tube detection methods, the present method used the amplicon‐specific melt‐profiles to evaluate the status of the SCAR markers, thus eliminating the need for gel‐based analysis. Results also showed feasibility of multiplex analysis of two markers with well‐separated melting profiles. Overall, the approach is a rapid, convenient and cost‐effective method for high‐throughput screening of SCAR markers.  相似文献   
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