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1.
《Cytokine》2015,74(2):283-287
Encephalitic listeriosis in sheep is a life-threatening disease. However, little is known about the cytokine response and their predictive value in this disease. The aim of present study was to assess the prognostic significance of Tumor Necrosis Factor-α (TNF-α), Interleukin-12(p40) (IL-12 p40), Interleukin-6 (IL-6), and Interleukin 10 (IL-10) levels in cerebrospinal fluid (CSF) in sheep with encephalitic listeriosis. Fifty-nine ewes in 14 flocks were diagnosed clinically as having listeriosis. CSF was collected and subjected to bacteriological examination and estimation of selected cytokines. Twenty-eight ewes were confirmed to be infected with Listeria monocytogenes. Based on antimicrobial sensitivity test, sheep were treated and the outcome was recorded as survivors (n = 10) and non-survivors (n = 18). Cutoff points for CSF cytokines were determined by Receiver operating characteristic analysis (ROC). Association between levels of CSF cytokines and outcome of listeriosis was assessed by logistic regression. TNF-α, IL-6 and IL-12(p40) levels as well as TNF-α/IL-10 ratio were significantly higher in non-survivors than survivors (p = 0.002, 0.0021, 0.0033, and 0.001, respectively). However, IL-10 level was significantly lower in non-survivors than survivors (p = 0.0058). ROC analysis revealed that IL-6 and TNF-α/IL-10 ratio had the highest AUC values (0.98, 0.984, respectively). Final multivariate logistic regression model showed that TNF-α/IL-10 ratio was the only variable that has predictive value for mortality in diseased sheep (p: 0.001; OR: 7.2; 95% CI: 5.7–9.8). TNF-α showed a positive correlation with IL-12β (r = 0.917) and IL-6 (r = 0.965). IL-12 (p40) showed also a positive correlation with IL-6 (r = 0.906). However, IL-10 showed a negative correlation with TNF-α (r = −0.915), IL-12(p40) (r = −0.790), and IL-6 (r = −0.902). In conclusion, TNF-α/IL-10 ratio may provide predictive information about outcome of encephalitic listeriosis in sheep.  相似文献   
2.
绵羊线粒体DNA控制区5’端序列PCR-SSCP与序列分析   总被引:3,自引:1,他引:2  
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3.
The aim of the present study is to determine the characteristics of genotype and phenotype of Echinococcus granulosus derived from wild sheep and to compare them with the strains of E. granulosus sensu stricto (sheep-dog) and E. granulosus camel strain (camel-dog) in Iran. In Khojir National Park, near Tehran, Iran, a fertile hydatid cyst was recently found in the liver of a dead wild sheep (Ovis orientalis). The number of protoscolices (n=6,000) proved enough for an experimental infection in a dog. The characteristics of large and small hooks of metacestode were statistically determined as the sensu stricto strain but not the camel strain (P=0.5). To determine E. granulosus genotype, 20 adult worms of this type were collected from the infected dog. The second internal transcribed spacer (ITS2) of the nuclear ribosomal DNA (rDNA) and cytochrome c oxidase 1 subunit (COX1) of the mitochondrial DNA were amplified from individual adult worm by PCR. Subsequently, the PCR product was sequenced by Sanger method. The lengths of ITS2 and COX1 sequences were 378 and 857 bp, respectively, for all the sequenced samples. The amplified DNA sequences from both ribosomal and mitochondrial genes were highly similar (99% and 98%, respectively) to that of the ovine strain in the GenBank database. The results of the present study indicate that the morpho-molecular features and characteristics of E. granulosus in the Iranian wild sheep are the same as those of the sheep-dog E. granulosus sensu stricto strain.  相似文献   
4.
The synthesis of foreign proteins can be targeted to the mammary gland of transgenic animals, thus permitting commercial purification of otherwise unavailable proteins from milk. Genetic regulatory elements from the mouse whey acidic protein (WAP) gene have been used successfully to direct expression of transgenes to the mammary gland of mice, goats and pigs. To extend the practical usefulness of WAP promoter-driven fusion genes and further characterize WAP expression in heterologous species, we introduced a 6.8 kb DNA fragment containing the genomic form of the mouse WAP gene into sheep zygotes. Two lines of transgenic sheep were produced. The transgene was expressed in mammary tissue of both lines and intact WAP was secreted into milk at concentrations estimated to range from 100 to 500 mg/litre. Ectopic WAP gene expression was found in salivary gland, spleen, liver, lung, heart muscle, kidney and bone marrow of one founder ewe. WAP RNA was not detected in skeletal muscle and intestine. These data suggest that unlike pigs, sheep may possess nuclear factors in a variety of tissues that interact with WAP regulatory sequences. Though the data presented are based on only two lines, these findings suggest WAP regulatory sequences may not be suitable as control elements for transgenes in sheep bioreactors.  相似文献   
5.
Abstract. Cuticular sensilla on newly hatched larvae of Gasterophilus intestinalis De Geer (Diptera: Gasterophilidae) and Oestrus ovis (L.) were studied by scanning electron microscopy. Two types of trichoid sensilla, two types of coeloconic sensilla and a pit sensillum were present on the thoracic and abdominal segments of G. intestinalis larvae. Sensilla on larvae of O. ovis were similar although only one type of trichoid sensillum was present. Total number of sensilla were higher for O. ovis than for G. intestinalis (248 v . 214). Variation in numbers of sensilla is consistent with the concept that increasing numbers of sensilla are associated with increasingly complex searching behaviour required to locate suitable habitats for development.  相似文献   
6.
The ovine map is not yet well-developed, which represents a problem when looking for markers of a region of interest in sheep. A means of circumventing this is to use comparative mapping. In this study primers were determined using consensus sequences for the epidermal growth factor gene of humans, rats and mice, and an ovine epidermal growth factor gene fragment was amplified by polymerase chain reaction (PCR). A new set of specific ovine primers was chosen to study the polymorphism of this DNA fragment by denaturing gradient gel electrophoresis. Eighty-four individuals belonging to seven sheep breeds were studied with this technique and four alleles were detected. The heterozygosity rate was 0.57. Family analysis showed mendelian inheritance of the alleles. Usually, genetic analysis of type-I loci used in the comparative mapping is based on the detection of restriction fragment length polymorphisms in sheep DNA using cDNA probes from other species. Our work shows that another method, based on PCR and denaturing gradient gel electrophoresis techniques, can be efficiently used.  相似文献   
7.
8.
Enzymatic activities catalysing the inter-conversion of L-methionine and its oxy analogue 4-methylthio-2-oxobutyric acid (2,4-KMB) were detected in the liver, skeletal muscle and heart of the laboratory rat and of sheep. In both species the highest activity of methionine transamination was found in the liver and was located in the cytoplasm and mitochondria. We propose that physiological and nutritional role of the cytoplasmic methionine transamination is amination of 2,4 KMB and formation of L-methionine while in mitochondria the activity is responsible for disposal of excess methionine is oxidised through oxidative decarboxylation of 2,4 KMB.  相似文献   
9.
Stock grazing is essential in many habitats owned by the National Trust if their nature conservation interests are to be maintained or enhanced. In this review, the benefits of grazing cattle, sheep and other livestock in different habitat types are described, together with constraints imposed by tenancy agreements and difficulties in obtaining the most appropriate animal. The majority of upland heaths, calcareous grasslands and lowland/coastal heaths on Trust land are being grazed satisfactorily. However, the nature conservation interest of parklands is currently being eroded in part because of inappropriate grazing regimes. It is argued that the best use of stock in the future is in extensive grazing regimes.  相似文献   
10.
The extracellular matrix of different mammalian tissues is commonly used as scaffolds in the field of tissue engineering. One of these tissues, which has frequently been studied due to its structural and biological features, is the small intestine submucosal membrane. These research are mainly done on the porcine small intestine. However, a report has recently been published about a scaffold produced from the submucosal layer of the ovine small intestine. In the present study, ovine small intestine submucosal (OSIS) was decellularized in a modified manner and its histological, morphological, and biomechanical properties were studied. Decellularization was performed in two phases: physical and chemical. In this method, a chloroform-methanol mixture, enzymatic digestion, and a constant dose of sodium dodecyl sulfate (SDS) was used in the least agitation time and its histological property and biocompatibility were evaluated in the presence of adipose tissue-derived stem cells (ADSCs); furthermore, ADSCs were isolated with a simple method (modified physical washing non-enzymatic isolation). The results were showed that the use of OSIS could be effective and operative. Mechanical properties, histological structure and shape, and glycosaminoglycan content were preserved. In the SDS-treated group, more than 90% of the native cells of tissue were deleted, and also in this group, no toxicity was observed and cell proliferation was supported, compared to the untreated group. Therefore, our results indicate that ADSCs seeded on OSIS scaffold could be used as a new approach in regenerative medicine as hybrid or hydrogel application.  相似文献   
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