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91.
Systemic cladosporiosis is described in 25 merino sheep from a flock consisting 250 animals. The fungal pneumonia appeared after an intensive antibiotic treatment, because of a respiratory system disorder. The pen of the flock was humid and crowded, and animals had signs of respiratory distress, coughing, fever and anorexia. All of the ill animals died, and necropsy was performed on 10 sheep. The lesions were characterized by a multifocal pyogranulomatous pneumonia and an abomasitis. Severe hemorrhages were observed in the lungs. At the histopathological examination, severe vasculitis with thrombosis was observed in various organs, especially in the lungs and abomasums, suggestive for a hematogenous dissemination of the infection in these organs. Numerous PAS-positive fungal elements were seen in the pyogranulomatous foci. Dark green fungal colonies were seen in the blood agar and Sabouraud dextrose agar that were identified as Cladosporium cladosporioides. This report highlights that phaeohyphomycosis can cause a severe systemic and fatal disease in merino sheep under insufficient management conditions.  相似文献   
92.
The prevalence and antimicrobial susceptibilities of Staphylococci and Streptococci were assessed from subclinical mastitis cases. One hundred Coagulase-Negative Staphylococci (CNS) and 34 Streptoccocci were identified. The most frequently isolated species were Staphylococcus haemolyticus (27%) and Staphylococcus simulans (24%). Susceptible CNS species revealed the highest resistance to penicillin G (58%), ampicillin (48%), neomycin (20%), and oleandomycin (14%). CNS methicillin resistance rates within 82 isolates were 21.95% and 1.22% by disk diffusion and PCR methods, respectively. These results suggested the disk diffusion method was more prone to yield false positives. Partial sequencing of the 16S rRNA region from the mecA carrying isolate (S. haemolyticus) was homologous with S. haemolyticus sequences/accessions obtained from GenBank. However, the mecA gene sequence from this isolate was more closely allied with the S. aureus mecA gene of human origins. Identical sequence data was acquired from the National Center for Biotechnology Information (NCBI) database, suggesting horizontal gene transfer between the two species. CNS β-lactamase activity within 81 isolates was 29.63%. The most frequently isolated Streptococcus species were S. uberis (52%) and S. agalactiae (15%). Oleandomycin was the least effective antimicrobial agent on these isolates with 59% susceptibility. Results indicated that CNS and Streptococci exhibited various antimicrobial resistance responses. Consequently, isolation and identification of udder pathogens in herds suffering from subclinical agents is essential to select the most effective antimicrobial agent. Moreover, multiple resistance features of methicillin resistant (MR) isolates should be considered during antimicrobial susceptibility tests.  相似文献   
93.
The antifungal activities of volatile phase effects of essential oils from Origanum onites, O. syriacum, O. minutiflorum, O. vulgare, O, marjorana, Thymus vulgaris, T. serpyllum, Rosmarinus officinalis, Salvia officinalis and Micromeria fruticosa were evaluated for their ability to inhibit growth of three vegetative compatibility groups (VCGs) of Verticillium dahliae. Carvacrol was the main component of O. onites, O. minutiflorum and O. vulgare essential oils, while γ-terpinene was the main component of O. syriacum. P-cymene and thymol were the dominant component of T. vulgaris and T. serpyllum. β- thujone and l-camphor were the main component of S. officinalis. Polegone and isomenthone were the dominant components of M. fruticosa essential oil. Based on the in vitro test, the degree of fungistatical effects can be ranked in the following order of inhibition: O. syriacum = O. onites = O. minutiflorum = O. vulgare = T. vulgaris > T. serpyllum > M. fruticosa > S. officinalis = O. marjorana > R. officinalis. The essential oils of S. officinalis, O. marjorana and R. officinalis displayed moderate antifungal activity, that increased with increasing concentrations. Among the VCGs, VCG2A and VCG4B were found to be highly sensitive to the essential oils. The essential oils of O. syriacum, O. onites, O. minutiflorum, O. vulgare and T. vulgaris were the most efficacious, demonstrating strong antifungal activity against all of the tested VCGs of V. dahliae at relatively low concentrations and they could find practical application as natural fungicides in the prevention and protection of plants from V. dahliae infections.  相似文献   
94.
The aim of this study was to evaluate the possible protective effects of quercetin (QE) against cholestatic oxidative stress and liver damage in the common bile duct ligated rats. A total of 24 male Wistar albino rats were divided into three groups: control, bile duct ligation (BDL) and BDL + received QE; each group contain 8 animals. The rats in QE treated groups were given QE (15 mg/kg) once a day intraperitoneally for 4 weeks starting 3 days prior to BDL operation. The changes demonstrating the bile duct proliferation and fibrosis in expanded portal tracts include the extension of proliferated bile ducts into lobules, mononuclear cells, and neutrophil infiltration into the widened portal areas were observed in BDL group. Treatment of BDL with QE attenuated alterations in liver histology. The alpha smooth muscle actin (α-SMA), transforming growth factor beta (TGF-β1) positive cells and the activity of TUNEL in the BDL were observed to be reduced with the QE treatment. The data indicate that QE attenuates BDL-induced cholestatic liver injury, bile duct proliferation, and fibrosis. The hepatoprotective effect of QE is associated with antioxidative potential.  相似文献   
95.
Salvia ballsiana (Rech. fil.) Hedge, previously known only from the type gathering, is a local endemic species from Turkey. The species was first collected from Gölbaşı (Malatya) by E. K. Balls in 1935, and was not collected again until 2008, when we found it in Gerger (Adıyaman). The diagnostic morphological characters of this rare endemic species are discussed, including its anatomical, palynological and nutlet micromorphological features. Morphological characteristics of leaves, calyces, corollas and types of stamens are useful for sectional and specific delimitation in Salvia . Anatomical characters such as number of ray rows in roots, distance between vascular bundles in stems, mesophyll structures in leaves, shape of mid-rib and presence/absence of sclerenchymatic tissue in petioles are of taxonomic significance. In addition, size, shape and ornamentation of pollen grains and nutlets are diagnostic.  相似文献   
96.
Hypercholesterolemia and lipid peroxidation play complementary roles in atherosclerosis. Artichoke (Cynara scolymus L., Asteraceae) leaf extract (ALE), rich in antioxidants, has cholesterol-reducing effect. We investigated the effect of ALE on serum and hepatic lipid levels and pro-oxidant–antioxidant balance in the liver and heart of hypercholesterolemic rats. Rats were fed on 4% (w/w) cholesterol and 1% cholic acid (w/w) supplemented diet for 1 month. ALE (1.5 g/kg/day) was given by gavage during the last 2 weeks. High cholesterol (HC) diet caused significant increases in serum and liver cholesterol and triglyceride levels. It increased malondialdehyde (MDA) and diene conjugate (DC) levels in both tissues. Hepatic vitamin E levels and hepatic and cardiac glutathione peroxidase (GSH-Px) activities decreased, but superoxide dismutase and glutathione transferase activities, glutathione, and vitamin C levels remained unchanged due to HC diet. Serum cholesterol and triglyceride levels and ratio of cholesterol to high-density lipoprotein (HDL)-cholesterol decreased in ALE plus HC-treated rats, but liver cholesterol and triglyceride levels remained unchanged. Significant decreases in hepatic and cardiac MDA and DC levels and increases in hepatic vitamin E and GSH-Px activities were observed in ALE-treated hypercholesterolemic rats. Our results indicate that ALE decreases serum lipids and hypercholesterolemia-induced pro-oxidant state in both tissues.  相似文献   
97.
This study was conducted to evaluate the probiotic properties of Pediococcus pentosaceus OZF isolated from human breast milk. The results obtained so far suggest that the strain is resistant to low pH, bile salt, pepsin and pancreatin, so it could survive while passing through the upper part of the gastrointestinal tract and reveal its potential probiotic action on host organism. The strain was non-pathogenic (γ-hemolytic), produced anti-Listerial bacteriocin, exhibited a strong autoaggregating phenotype (85.71%) and demonstrated 6.26 and 12.99% coaggregation with Salmonella enterica serotype Typhimurium SL 1344 and Escherichia coli LMG 3083 (ETEC), respectively. The degree of adhesion of Ped. pentosaceus OZF to the human Caco-2 cell line was investigated and when compared to the adhesion of pathogenic strains tested, it was shown to inhibit the growth of human enterotoxigenic E. coli LMG 3083 (ETEC) and of Salm. Typhimurium SL 1344. Ped. pentosaceus OZF seems to adhere to human intestinal cells via mechanisms that involve different combinations of carbohydrate and lipid factors on the bacteria and eukaryotic cell surface. The percentage of adhesion to n-hexadecane was 34% showing that the surface was rather hydrophilic. Higher affinity displayed by Ped. pentosaceus OZF for chloroform demonstrates the basic property of a cell, which may be due to the presence of carboxylic groups on the cell surface.  相似文献   
98.
99.
We use replica-exchange molecular dynamics (REMD) to interrogate molecular structures and properties of four engineered dodecapeptides (in solution, in the absence of a surface) that have been shown to bind to quartz with different propensities. We find that all of the strong-binding peptides feature some polyproline type II secondary structure, have less conformational freedom, and feature fewer intrapeptide hydrogen bonds compared with the weak binder. The regions of contiguous proline content in a given sequence appear to play a role in fostering some of these properties of the strong binders. For preliminary insights into quartz binding, we perform lattice-matching studies between a grid corresponding with the quartz (100) surface and the strong-binding peptide REMD structures. Our findings indicate a commonality among the putative contact residues, even for peptide structures with very different backbone conformations. Furthermore, interpeptide interactions in solution are studied. Our preliminary findings indicate that the strong-binder interpeptide contacts are dominated by weak, nonspecific hydrophobic interactions, while the weak-binding peptide shows more variable behavior due to the distribution of charged residues. In summary, the solution structures of peptides appear to be significant. We propose that these differences in their intra- and interpeptide interactions can influence their propensity to bind onto a solid substrate.  相似文献   
100.
Metabolic syndrome (MetS) is a complex entity consisting of multiple interrelated factors including insulin resistance, central adiposity, dyslipidemia, endothelial dysfunction and atherosclerotic disease, low-grade inflammation, and in males, low testosterone levels. MetS has been linked to a number of urologic diseases including nephrolithiasis, benign prostatic hyperplasia and lower urinary tract symptoms, erectile dysfunction, male infertility, female incontinence, and prostate cancer. This article reviews the relationships between MetS and these entities. Urologists need to be cognizant of the impact that MetS has on urologic diseases as well as on overall patient health.  相似文献   
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