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41.
Rui Figueiredo Roderick Card Carla Nunes Manal AbuOun Mary C. Bagnall Javier Nunez Nuno Mendon?a Muna F. Anjum Gabriela Jorge da Silva 《PloS one》2015,10(8)
Salmonella enterica is a zoonotic foodborne pathogen that causes acute gastroenteritis in humans. We assessed the virulence potential of one-hundred and six Salmonella strains isolated from food animals and products. A high through-put virulence genes microarray demonstrated Salmonella Pathogenicity Islands (SPI) and adherence genes were highly conserved, while prophages and virulence plasmid genes were variably present. Isolates were grouped by serotype, and virulence plasmids separated S. Typhimurium in two clusters. Atypical microarray results lead to whole genome sequencing (WGS) of S. Infantis Sal147, which identified deletion of thirty-eight SPI-1 genes. Sal147 was unable to invade HeLa cells and showed reduced mortality in Galleria mellonella infection model, in comparison to a SPI-1 harbouring S. Infantis. Microarray and WGS of S. Typhimurium Sal199, established for the first time in S. Typhimurium presence of cdtB and other Typhi-related genes. Characterization of Sal199 showed cdtB genes were upstream of transposase IS911, and co-expressed with other Typhi-related genes. Cell cycle arrest, cytoplasmic distension, and nuclear enlargement were detected in HeLa cells infected by Sal199, but not with S. Typhimurium LT2. Increased mortality of Galleria was detected on infection with Sal199 compared to LT2. Thus, Salmonella isolates were rapidly characterized using a high through-put microarray; helping to identify unusual virulence features which were corroborated by further characterisation. This work demonstrates that the use of suitable screening methods for Salmonella virulence can help assess the potential risk associated with certain Salmonella to humans. Incorporation of such methodology into surveillance could help reduce the risk of emergence of epidemic Salmonella strains. 相似文献
42.
Reactive oxygen species are thought to induce cellular damage and to play a pathological role in several human diseases. Tetradecylthioacetic acid (TTA) was previously reported to prevent the oxidative modification of low-density lipoprotein (LDL) particles and to act as an antioxidant. In this study we present a new fatty acid analogue, namely tetradecylselenoacetic acid (TSA), in which the sulfur atom of TTA is replaced by a selenium atom. TSA was more potent than TTA in increasing the lag time before the onset of LDL oxidation and this effect was dose dependent. TTA and TSA were shown to reduce the iron-ascorbate-induced microsomal lipid peroxidation, TSA being more efficient than TTA. TTA and TSA, in the presence of iron, interacted with the superoxide radical as assessed by direct and indirect testing methods. TSA like TTA failed to scavenge 1.1-diphenyl-2-picrylhydrazyl radicals. TSA bound copper ions as shown by the wavelength spectra measurement. These results suggest that TTA and TSA exert their antioxidant capacity by interaction with copper or iron ions in radical scavenging, TSA being more potent than TTA. Nevertheless, a chelating effect resulting in chemically inactive metal ions cannot be excluded. 相似文献
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Background
Metoclopramide is a dopamine D2-receptor antagonist used as an antiemetic and gastroprokinetic agent in man and animals. The drug causes sedation as a side effect in man. Such a sedative action of metoclopramide has not been documented in the chicken as the drug is not used clinically in this species. The present study examines the central nervous system depressant effects of metoclopramide in 7–14 days old broiler chicks.Results
Injection of metoclopramide at 50, 100 and 200 mg/kg, subcutaneously (s.c.) induced sedation in the chicks in a dose dependent manner. The chicks manifested, within 3.6–19 minutes of metoclopramide injection, signs of sedation characterized by drooping of the head and wings, closed eyelids, reduced motility and decreased distress calls. The duration of sedation ranged between 37.2 to 163.4 minutes. Metoclopramide at 100 and 200 mg/kg induced, within 12.2 and 6.2 minutes, sleep (loss of righting reflex) for 43.8 and 158.6 minutes, respectively. The median effective doses of metoclopramide for induction of sedation and sleep in the chicks were 11 and 53 mg/kg, s.c., respectively. Lower doses of metoclopramide (5 and 10 mg/kg, s.c.) significantly decreased the open-field activity of the chicks and increased the durations of their tonic immobility. All treated-chicks recovered from the central nervous system depressant effect of metoclopramide without any observable adverse effects.Conclusion
The data suggest that metoclopramide induces central nervous system depression in chicks, and the drug could have potential clinical applications as a sedative-hypnotic agent in avian species not intended for human consumptions. 相似文献44.
Michael W. Stuck Shannon M. Conley Muna I. Naash 《The Journal of biological chemistry》2015,290(46):27901-27913
The photoreceptor-specific glycoprotein retinal degeneration slow (RDS, also called PRPH2) is necessary for the formation of rod and cone outer segments. Mutations in RDS cause rod and cone-dominant retinal disease, and it is well established that both cell types have different requirements for RDS. However, the molecular mechanisms for this difference remain unclear. Although RDS glycosylation is highly conserved, previous studies have revealed no apparent function for the glycan in rods. In light of the highly conserved nature of RDS glycosylation, we hypothesized that it is important for RDS function in cones and could underlie part of the differential requirement for RDS in the two photoreceptor subtypes. We generated a knockin mouse expressing RDS without the N-glycosylation site (N229S). Normal levels of RDS and the unglycosylated RDS binding partner rod outer segment membrane protein 1 (ROM-1) were found in N229S retinas. However, cone electroretinogram responses were decreased by 40% at 6 months of age. Because cones make up only 3–5% of photoreceptors in the wild-type background, N229S mice were crossed into the nrl−/− background (in which all rods are converted to cone-like cells) for biochemical analysis. In N229S/nrl−/− retinas, RDS and ROM-1 levels were decreased by ∼60% each. These data suggest that glycosylation of RDS is required for RDS function or stability in cones, a difference that may be due to extracellular versus intradiscal localization of the RDS glycan in cones versus rods. 相似文献
45.
Anthony H. Taylor Muna S. Abbas Marwan A. Habiba Justin C. Konje 《Histochemistry and cell biology》2010,133(5):557-565
Plasma anandamide (AEA) levels fluctuate throughout the menstrual cycle and in early pregnancy in a pattern suggesting its
involvement in implantation and early pregnancy maintenance through mechanisms that might involve its binding to cannabinoid
receptors CB1 and CB2. Plasma AEA levels are maintained by the actions of the enzymes fatty acid amide hydrolase (FAAH) and
N-acylphosphatidylethanolamine-phospholipase D (NAPE-PLD). All of these component parts of the ‘endocannabinoid system’ have
been demonstrated in rodent but not in human uteri. This study aimed to demonstrate the presence of the endocannabinoid system
in the human uterus and catalogue its modulation. Immunohistochemical techniques were employed to localise and determine the
distribution of immunoreactive CB1, CB2, FAAH, and NAPE-PLD in well-characterised menstrual cycle biopsy samples. Immunoreactive
CB1 and CB2 were widely distributed throughout the uterine tissue. In the myometrium and endometrium, smooth muscle cells
were immunoreactive, although the vascular smooth muscle cells in both tissues were more so. In the endometrium, CB1 and CB2
immunoreactivity was primarily restricted to the glandular epithelium and expression was unrelated to the phase of the cycle.
FAAH immunoreactivity in the endometrium was highest in the mid-proliferative gland and mid-secretory stroma, whilst NAPE-PLD
immunoreactivity was down-regulated in the secretory epithelial gland compared to the proliferative epithelial gland and unaffected
in the stroma. These data indicate that elements of the ‘endocannabinoid system’ coexist in many cell types within the uterus
and may provide insight into the sites of action of endogenous and exogenous cannabinoids during endometrial transformation. 相似文献
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47.
Davies JS Gevers EF Stevenson AE Coschigano KT El-Kasti MM Bull MJ Elford C Evans BA Kopchick JJ Wells T 《American journal of physiology. Endocrinology and metabolism》2007,292(5):E1483-E1494
This study describes the previously uncharacterized ontogeny and regulation of truncal adipose reserves in the profoundly GH-deficient dwarf (dw/dw) rat. We show that, despite normal proportionate food intake, dw/dw rats develop abdominal leanness and hypoleptinemia (circulating leptin halved in dw/dw males, P < 0.05) during puberty. This contrasts with the hyperleptinemia seen in moderately GH-deficient Tgr rats (circulating leptin doubled at 6 wk of age, P < 0.05) and in GH receptor-binding protein (GHR/BP)-null mice (circulating leptin doubled; P < 0.05). This lean/hypoleptinemic phenotype was not completely normalized by GH treatment, but dw/dw rats developed abdominal obesity in response to neonatal MSG treatment or maintenance on a high-fat diet. Unlike Tgr rats, dw/dw rats did not become obese with age; plasma leptin levels and fat pad weights became similar to those in wild-type rats. In contrast with truncal leanness, tibial marrow adiposity was normal in male and doubled in female dwarves (P < 0.01), this increase being attributable to increased adipocyte number (P < 0.01). Neonatal MSG treatment and high-fat feeding elevated marrow adiposity in dw/dw rats by inducing adipocyte enlargement (P < 0.05). These results demonstrate that, despite lipolytic influence of GH, severe GH deficiency in dw/dw rats is accompanied by a paradoxical leanness. This lean/hypoleptinemic phenotype is not solely attributable to reduced GH signaling and does not appear to result from a reduction in nutrient intake or the ability of dw/dw adipocytes to accumulate lipid. Disruption of preadipocyte differentiation or adipocyte proliferation in the dw/dw rat may lead to the development of this unusually lean/hypoleptinemic phenotype. 相似文献
48.
Hurley D Araki H Tamada Y Dunmore B Sanders D Humphreys S Affara M Imoto S Yasuda K Tomiyasu Y Tashiro K Savoie C Cho V Smith S Kuhara S Miyano S Charnock-Jones DS Crampin EJ Print CG 《Nucleic acids research》2012,40(6):2377-2398
Gene regulatory networks inferred from RNA abundance data have generated significant interest, but despite this, gene network approaches are used infrequently and often require input from bioinformaticians. We have assembled a suite of tools for analysing regulatory networks, and we illustrate their use with microarray datasets generated in human endothelial cells. We infer a range of regulatory networks, and based on this analysis discuss the strengths and limitations of network inference from RNA abundance data. We welcome contact from researchers interested in using our inference and visualization tools to answer biological questions. 相似文献
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50.
Mohammed S Ali-Shtayeh Rana M Jamous Jehan H Al-Shafie' Wafa' A Elgharabah Fatemah A Kherfan Kifayeh H Qarariah Isra' S Khdair Israa M Soos Aseel A Musleh Buthainah A Isa Hanan M Herzallah Rasha B Khlaif Samiah M Aiash Ghadah M Swaiti Muna A Abuzahra Maha M Haj-Ali Nehaya A Saifi Hebah K Azem Hanadi A Nasrallah 《Journal of ethnobiology and ethnomedicine》2008,4(1):1-13