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1.
The present study was conducted to identify natural products in the bioactive fractions of Lagenaria siceraria mesocarp. Column chromatography and gas chromatography-mass spectrometry (GC-MS) was used for separation and identification of phytochemicals. Methanolic extract and its fractions displayed alpha-amylase and xanthine oxidase inhibitory activities comparable to standard drugs. GC-MS analysis of the fractions and column eluates revealed the presence of a variety of chemical compounds, including 4-(methoxymethyl)phenol, 2,2?-methylenebis{6(1,1-dimethylethyl)-4-ethyl}phenol, methyl 2-hydroxy-3-phenylpropanoate, oxacyclododecane-2,8-dione, N-(2-(4-hydroxyphenyl)ethyl] acetamide, 2,3-Epoxycarane, 4-(propan-2-yl)benzaldehyde, octadec-1-ene, 4a-methyl-1-methylidene-1,2,3,4,4a,9,10,10a-octahydrophenanthrene, 2,6-di(propan-2-yl)naphthalene, methyl 3-(4-hydroxy-3,5-dimethylphenyl)propanoate, 4,8a-dimethyl-6-(prop-1-en-2-yl)-3,5,6,7,8,8a-hexahydronaphthalen-2(1H)-one 1,3-dihydro-2-benzofuran, methyl N-hydroxybenzenecarboximidoate, linoleic acid, and palmitic acid. Many of these compounds are being reported for the first time from this plant, the presence of which may explain, at least partly, its medicinal efficacy. The fruit possesses significant anti-enzymatic properties against alpha-amylase and xanthine oxidase, and the most active compounds of mesocarp of the fruit appear in ethyl acetate fraction of its methanolic extract.  相似文献   
2.
In South America, the whitefly Aleurotrachelus socialis is one of the principal pests of cassava (Manihot esculenta Crantz), reaching high population levels throughout the Andean region. Management of this species is primarily based upon the use of insecticides, while biological control has received limited attention. Till present, knowledge of A. socialis natural enemies is restricted to occasional records of predators and parasitoids. In this study, we developed PCR primer sets specific for the cassava whitefly, A. socialis, to identify their predator community in Colombian cassava. Eleven percent of 586 predator specimens (representing 131 taxa from 29 families) tested positive for cassava whitefly DNA. Of the 21 predator taxa that consumed cassava whiteflies, an unidentified netwing beetle (Lycidae), an unidentified spider species (Araneae), Harmonia axyridis (Coleoptera: Coccinellidae), a Cereaochrysa sp. (Neuroptera: Chrysopidae), and a Leucochrysa sp. (Chrysopidae) were the taxa that consumed cassava whiteflies most frequently under field conditions. Two abundant predators in the system, Delphastus sp. (Coccinellidae) and the long-legged fly, Condylostylus sp. (Diptera: Dolichopodidae), were both positive for whitefly DNA, but did not have the strongest trophic linkage to the pest relative to other predators. This study shows that a diverse predator community affects cassava whitefly in southern Colombia, and provides the groundwork for the design of cassava production systems with minimal pesticide inputs.  相似文献   
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The mucoadhesive Chitosan (CS) nanofibers as a drug delivery system were developed. Chitosan was modified via the immobilization of thiol groups from L-cysteine as a mucoadhesive reagent. The mucoadhesive properties of the chitosan nanofibers were evaluated by tensiometer set and via tensile studies. Drug and mucoadhesive agent loading lead to decrease diameters and increased porous of nanofibers. The release of Tetracycline (Tet) and Triamcinolone (Tri) were increased with increasing immersion time and it became constant at long immersion times. Mucoadhesion studies were done at pH 2–7 and in pH 6 maximum mucoadhesive properties observed. Release studies demonstrated a sustained release of both drug continued up to 48 hours. Microbial studies were performed on the nanofibers. The drug delivery system represented a novel tool for improve the therapeutic efficacy of various drugs that are poorly absorbed from the gastrointestinal tract. Also it is an efficient system for treatment of oral ulceration.  相似文献   
5.
Helicobacter‐like organisms are frequently found in canine stomachs, but the relationship between such organisms and gastric pathology has not been established. However, some such organisms have zoonotic importance. The aims of this study were to evaluate the morphological and biochemical characteristics of cultivable canine gastric Helicobacter‐like organisms (GHLOs) in pets and stray dogs and their prevalence in these two groups of dogs. Specimens were taken by gastroscopy from 30 clinically healthy stray dogs and 30 pet dogs. Cultures were positive from biopsies of 11/30 of stray and 6/30 of pet dogs. The isolated Helicobacters were observed by light microscopy and studied by biochemical, physiological and PCR analysis. Some of the isolated GHLO's displayed atypical shapes that were similar to Helicobacter pylori or Helicobacter acinonychis in stray dogs’ cytological examinations. They had 2–3 helices and were smaller than other canine GHLOs. One of these atypical Helicobacter strains was cultured. It was not possible to distinguish such strains by routine PCR and biochemical evaluations. Electron microscopy showed a smaller Helicobacter (2 μm in length) with 2 or 3 helixes. This study demonstrates that not all canine gastric Helicobacters are 5–15 μm in length, as has been previously proposed, and portrays the need for further investigation of canine GHLOs.  相似文献   
6.
Adenoviruses are frequent infectious agents in different poultry species. The traditional, serological typing of new isolates by virus neutralisation tests is now in transition to be replaced by PCR and sequencing. The first PCRs, recommended for the detection of adenoviruses, had been designed to target the gene of the major capsid protein, the hexon. In birds, members of three different genera of the family Adenoviridae may occur. Accordingly, three specific hexon PCRs had to be elaborated for the detection of adenoviruses in poultry. A significantly more sensitive PCR, targeting the viral DNA-dependent DNA polymerase gene, has been described recently. This method proved to be an efficient alternative for the general detection of adenoviruses irrespective of their genus affiliation. Fowl adenoviruses (FAdVs), isolated from chicken to date, comprise twelve serotypes classified into five virus species (FAdV-A to E). The polymerase gene sequence has been determined yet only from three FAdV types representing three species. In the present work, the panel of polymerase gene sequences was completed with those of the rest of FAdVs. The newly determined sequences will facilitate the identification of new FAdV isolates as an existing species or as a putative new FAdV. Once the polymerase sequence is known, more specific PCRs for the amplification of the hexon and other genes can be designed and performed according to the preliminary species classification.  相似文献   
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Vermicompost can play an effective role in plant growth and development and also in reducing harmful effects of various environmental stresses on plants due to its porous structure, high water storage capacity, having hormone-like substances and plant growth regulators and also high levels of macro and micro nutrients. The aim of this study was to investigate the effects of vermicompost and salinity interactions on some morphological and physiological features and concentration of mineral elements of bean (Phaseolus vulgaris L. cv. Light Red Kidney) cultivar. A factorial experimental with five different volumetric ratios of vermicompost and sand, including to: 0:100; 10:90; 25:75; 50:50 and 75:25 and four levels of salinity [20, 40, 60 and 80 mmol l?1 sodium chloride (NaCl)], and control was conducted base on Randomized Complete Block Design with three replications. Bean seeds were sowed in plastic pots, the seedlings being sampled 42 days old (flowering stage).The results showed that vermicompost had significant effect on all studied traits under stress and non-stress (p ≤ 0.05).In this experiment, the vermicompost significantly increased the photosynthetic rate and concentrations of potassium (K+) and calcium (Ca2)+in leaf and root tissues. In salinity levels of 20, 40 and 60 mmol l?1NaCl, all subjected ratios of vermicompost and in 80 mmol l?1NaCl the ratios of 10% and 75% vermicompost, significantly ameliorated negative effects of salinity. In both stress and non-stress conditions, using 10% volume of vermicompost is recommended to improve the growth of bean plants.  相似文献   
9.
ObjectiveTo evaluate the cardiopulmonary effects of anaesthesia induced and maintained with propofol in acepromazine pre-medicated donkeys.Study designProspective experimental study.AnimalsSix healthy male donkeys weighing 78–144 kg.MethodsDonkeys were pre-medicated with intravenous (IV) acepromazine (0.04 mg kg−1). Ten minutes later, anaesthesia was induced with IV propofol (2 mg kg−1) and anaesthesia maintained by continuous IV infusion of the propofol (0.2 mg kg−1 minute−1) for 30 minutes. Baseline measurements of physiological parameters, and arterial blood samples were taken before the acepromazine administration, then 5, 15, 30, 45, and 60 minutes after the induction of anaesthesia. Changes from baseline were analysed by anova for repeated measures.ResultsWhen compared with baseline (standing) values, during anaesthesia heart rate increased throughout: significant at 5 (p = 0.001) and 15 (p = 0.015) minutes. Mean arterial blood pressure increased significantly only at 15 minutes (p < 0.001). Respiratory rate and arterial pH did not change significantly. PaO2 was lower throughout anaethesia, but this only reached significance at 15 minutes (p = 0.041). PaCO2 was statistically (but not clinically) significantly reduced at the times of 30 (p = 0.02), 45 (p = 0.01) and 60 (p = 0.04). Rectal temperature decreased significantly at all times of the study.Conclusions and clinical relevanceAdministration of propofol by the continuous infusion rate for the maintenance of anaesthesia resulted in stable cardiopulmonary effects and could prove to be clinically useful in donkeys.  相似文献   
10.
Background: Bone marrow stromal cells (BMSC) have been successfully employed for movement deficit recovery in spinal cord injury (SCI) rat models. One of the unsettled problems in cell transplantation is the relative high proportion of cell death, specifically after neural differentiation. According to our previous studies, p75 receptor, known as the death receptor, is only expressed in BMSC in a time window of 6-12 hours following neural induction. Moreover, we have recently reported a decreased level of apoptosis in p75-suppressed BMSC in vitro. Therefore, our objective in this research was to explore the functional effects of transplanting p75:siRNA expressing BMSC in SCI rats. Methods: Laminectomy was performed at L1 vertebra level to expose spinal cord for contusion using weight-drop method. PBS-treated SCI rats (group one) were used as negative controls, in which cavitations were observed 10 weeks after SCI. pRNA-U6.1/Hygro- (group two, as a mock) and pRNA-U6.1/Hygro-p75 shRNA- (group three) transfected BMSC were labeled with a fluorescent dye, CM-DiI, and grafted into the lesion site 7 days after surgery. The Basso-Beattie-Bresnehan locomotor rating scale was performed weekly for 10 weeks. Results: There was a significant difference (P≤0.05) between all groups of treated rats regarding functional recovery. Specifically, the discrepancy among p75 siRNA and mock-transfected BMSC was statistically significant. P75 siRNA BMSC also revealed a higher level of in vivo survival compared to the mock BMSC. Conclusion: Our data suggest that genetically modified BMSC that express p75:siRNA could be a more suitable source of cells for treatment of SCI. Key Words: Spinal cord injury (SCI), Apoptosis, Bone marrow stromal cells (BMSC)  相似文献   
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