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61.
Ghias Uddin Abdur Rauf Abdulaziz M. Al-Othman Simona Collina Muhammad Arfan Gowhar Ali Inamullah Khan 《Fitoterapia》2012
Pistacia integerrima Stewart in traditionally used as folk remedy for various pathological conditions including diabetes. In order to identify the bioactive compound responsible for its folk use in diabetes, a phytochemical and biological study was conducted. Pistagremic acid (PA) was isolated from the dried galls extract of P. integerrima. Strong α-glucosidase inhibitory potential of PA was predicted using its molecular docking simulations against yeast α-glucosidase as a therapeutic target. Significant experimental α-glucosidase inhibitory activity of PA confirmed the computational predictions. PA showed potent enzyme inhibitory activity both against yeast (IC50: 89.12 ± 0.12 μM) and rat intestinal (IC50: 62.47 ± 0.09 μM) α-glucosidases. Interestingly, acarbose was found to be more than 12 times more potent an inhibitor against mammalian (rat intestinal) enzyme (having IC50 value 62.47 ± 0.09 μM), as compared to the microbial (yeast) enzyme (with IC50 value 780.21 μM). Molecular binding mode was explored via molecular docking simulations, which revealed hydrogen bonding interactions between PA and important amino acid residues (Asp60, Arg69 and Asp 70 (3.11 Å)), surrounding the catalytic site of the α-glucosidase. These interactions could be mainly responsible for their role in potent inhibitory activity of PA. PA has a strong potential to be further investigated as a new lead compound for better management of diabetes. 相似文献
62.
Tedeschi G Taverna F Negri A Piccinini R Nonnis S Ronchi S Zecconi A 《Veterinary microbiology》2009,134(3-4):388-391
Staphylococcus aureus is the most common aetiologic agent of contagious bovine mastitis. Studies of the molecular epidemiology of S. aureus strongly suggest that some genetic subsets of strains are particularly well adapted for causing infections in cattle. This communication reports the setup of experimental protocols to identify the immunogenic proteins expressed by one of the most common field isolated strain of S. aureus responsible for sub-clinical mastitis cases. The serological proteome analysis (SERPA) approach applied consists of three main steps: two-dimensional electrophoresis-based separation of the proteins contained in field isolated S. aureus extracts enriched for surface proteins, detection of immunogenic spots using anti-serum collected from sub-clinical mastitis cases and identification of antigens by mass spectrometric-based methodologies. The study allowed to identify three immunogenic proteins: DNAase translocase FtsK, ribosomal proteins S1 and a Tell-like protein. 相似文献
63.
AI Iorga L Valentini T De Santis B Ambruosi M Albrizio AC Guaricci M Caira ME Dell'Aquila 《Reproduction in domestic animals》2009,44(S2):263-268
The μ-opioid receptor (MOR) is expressed in bovine, human, equine and canine oocytes, and in seasonal breeders, it is expressed with higher intensity during the anoestrous phase. Supplementation of in vitro maturation (IVM) medium with opioid agents, agonists or antagonists, was shown to affect oocyte maturation in several species such as rat, bovine and equine. This study reports the effects of supplementing IVM medium with naloxone (Nx), an opioid antagonist, on nuclear and cytoplasmic maturation rate of oocytes recovered from anoestrous bitches. Cytoplasmic maturation was examined in terms of mitochondrial (mt) distribution. In order to confirm the receptor-mediated action of Nx, in oocytes of anoestrous bitches, MOR expression was analyzed by Western blot. Cumulus–oocyte complexes, recovered from the ovaries of bitches in anoestrous, were cultured in vitro and Nx was added at the concentrations of 1 × 10−6 , 1 × 10−8 and 1 × 10−10 m . The rate of oocytes resuming meiosis after culture in presence of 1 × 10−6 m Nx (29%) was significantly higher than that of oocytes of control group (12%; p < 0.05). However, treatment with Nx did not affect mt distribution pattern. In denuded oocytes and in corresponding cumulus cells, a doublet of 65 and 50 kDa was observed. We conclude that, in oocytes of anoestrous bitches, MOR is expressed and Nx significantly improves nuclear maturation rate. Further studies should be performed to elucidate the expression of other opioid receptors, such as δ and κ, and possible interactive effects of their antagonists on canine oocyte maturation. 相似文献
64.
The effectiveness of enilconazole (4 weekly rinses with a 0.2% solution) or griseofulvin (50mg/kg twice daily for 40 days) following a pre-treatment with oral lufenuron (100mg/kg by-weekly for 8 weeks) was tested on 25 (11+14) Microsporum canis infected cats. Control animals were treated with lufenuron, griseofulvin and enilconazole alone. At day 150 pre-treated animals were culturally negative and clinically cured. While lufenuron alone was found to be ineffective against M canis infection, an immunomodulatory effect of the drug can be suggested, as reported in literature. Its use could be reserved to long-lasting infections, unsuccessfully treated with conventional drugs. Further studies are required to clearly establish the possible adjuvant effect of this molecule when used prior to enilconazole or griseofulvin. 相似文献
65.
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67.
Radaelli ST Platt SR 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(2):159-163
The clinical records of 23 dogs (1990-1999) with histopathologically confirmed bacterial meningoencephalomyelitis were evaluated retrospectively. No breed, age, sex, or weight predisposition was found. All the dogs presented with clinical signs of a brain lesion, whereas 5 of 23 had neck pain. Pyrexia was detected in 11 of 23 dogs on admission. CBCs revealed neutrophilic leucocytosis in 7 of 21 dogs and thrombocytopenia in 3 of 21 dogs. The serum chemistry profiles were abnormal in 15 of 21 dogs. The results of cerebrospinal fluid (CSF) analysis were abnormal in 13 of 14 dogs and aerobic CSF culture was positive for bacteria in 1of 8 samples. At postmortem examination, the lesions were localized to the central nervous system. Escherichia coli, Streptococcus, and Klebsiella spp were the most frequently isolated bacteria from cultures collected at postmortem examination. Twelve papers reporting 51 total clinical cases of canine bacterial meningoencephalomyelitis were reviewed. The clinical signs and results of the CBC, serum chemistry, blood culture, and CSF analysis were collated and compared with those of this study. The results of the CSF analysis in this study were similar to those in the literature. CSF cultures documented in the literature were positive for Staphylococcus, Pasteurella. Actinomyces, Nocardia spp, and various anaerobic species including Peptostreptococcus, Eubacterium, and Bacteroides spp. 相似文献
68.
Rota A Manuali E Caire S Appino S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(1):123-125
This paper describes the case of a 2-year-old English Bulldog with severe teratozoospermia that consisted mainly of "Dag-like" defects, which is strong coiling of the tail. Although libido, semen volume and sperm concentration were normal, sperm motility was 5.0%, and 93.3% of spermatozoa exhibited morphological abnormalities affecting the tail. Transmission electron microscopic examination of the spermatozoa revealed strong folding, coiling and fracture of sperm midpieces and tails, axonemal defects and the presence of swollen and unevenly distributed mitochondria. Taking into account the dog's history and examinations and the constantly high percentage of abnormal spermatozoa over time, the defect was considered to be genetic in origin. 相似文献
69.
Jelena Lujić Zoran Marinović Simona Sušnik Bajec Ida Djurdjevič Béla Urbányi Ákos Horváth 《Fish physiology and biochemistry》2018,44(6):1487-1498
Interspecific transplantation of germ cells from the brown trout Salmo trutta m. fario and the European grayling Thymallus thymallus into rainbow trout Oncorhynchus mykiss recipients was carried out in order to improve current practices in conservation of genetic resources of endangered salmonid species in the Balkan Peninsula. Current conservation methods mainly include in situ efforts such as the maintenance of purebred individuals in isolated streams and restocking with purebred fingerlings; however, additional ex situ strategies such as surrogate production are needed. Steps required for transplantation such as isolation of high number of viable germ cells and fluorescent labeling of germ cells which are to be transplanted have been optimized. Isolated and labeled brown trout and grayling germ cells were intraperitoneally transplanted into 3 to 5 days post hatch rainbow trout larvae. Survival of the injected larvae was comparable to the controls. Sixty days after transplantation, fluorescently labeled donor cells were detected within the recipient gonads indicating successful incorporation of germ cells (brown trout spermatogonia and oogonia—27%; grayling spermatogonia—28%; grayling oogonia—23%). PCR amplification of donor mtDNA CR fragments within the recipient gonads additionally corroborated the success of incorporation. Overall, the transplantation method demonstrated in this study presents the first step and a possible onset of the application of the germ cell transplantation technology in conservation and revitalization of genetic resources of endangered and endemic species or populations of salmonid fish and thus give rise to new or improved management strategies for such species. 相似文献
70.
Tommaso Chiti Lorenzo Gardin Lucia Perugini Roberta Quaratino Francesco Primo Vaccari Franco Miglietta Riccardo Valentini 《Biology and Fertility of Soils》2012,48(1):9-17
The aim of this work was to quantify the soil organic C (SOC) stock in the top 30 cm of mineral soil for the whole Italian
territory, according to the different land use types of the Intergovernmental Panel on Climate Change (IPCC) cropland category
(arable land, agroforestry, vineyards, olive groves, orchards and rice fields), as a basis for future land use scenarios and
to address mitigation policy at country level. A database for SOC stock was created with the data from the national project
denominated SIAS and partly from regional map reports. All data were referred to the year 2000 since they were derived from
surveys conducted from 1995 to 2005. The data were stratified according to the Italian climatic regions, the landscape position
and the IPCC cropland subcategories. Taking into account the uncertainty in the estimate, the mean SOC stock values of the
different subcategories show significant differences (p < 0.05) among climatic regions and landscapes, ranging from 41.9 ± 15.9 Mg C ha−1 in the vineyards to 63.3 ± 27.9 Mg C ha−1 in the rice fields. Generally, a small decrease of the SOC stock from the temperate regions toward the Mediterranean ones
is observed. Taking into account the mean value of each subcategory and the country area they occupied in 2000, the total
C stored in the upper 30 cm of soil was estimated at 490.0 ± 121.7 Tg C. The resulting estimate represents the 17% of the
value reported by another study for the soil of the whole country down to 50 cm depth, suggesting the importance of preserving
this large C pool. Considering the cropland category as a whole, the estimated mean SOC stock is 52.1 ± 17.4 Mg C ha−1, similar to that reported for other European countries, 50–60 Mg C ha−1. In conclusion, the assessment of the mean SOC stock of the different cropland land uses, landscape position and climate
regions could notably help when assessing the impact of different agricultural practices and future stock change evaluation. 相似文献