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141.
Epigenetic abnormalities in cloned animals are caused by incomplete reprogramming of the donor nucleus during the nuclear transfer step (first reprogramming). However, during the second reprogramming step that occurs only in the germline cells, epigenetic errors not corrected during the first step are repaired. Consequently, epigenetic abnormalities in the somatic cells of cloned animals should be erased in their spermatozoa or oocytes. This is supported by the fact that offspring from cloned animals do not exhibit defects at birth or during postnatal development. To test this hypothesis in cloned cattle, we compared the DNA methylation level of two imprinted genes (H19 and PEG3) and three non‐imprinted genes (XIST, OCT4 and NANOG) and two repetitive elements (Satellite I and Satellite II) in blood and sperm DNAs from cloned and non‐cloned bulls. We found no differences between cloned and non‐cloned bulls. We also analyzed the DNA methylation levels of four repetitive elements (Satellite I, Satellite II, Alpha‐satellite and Art2) in oocytes recovered from cloned and non‐cloned cows. Again, no significant differences were observed between clones and non‐clones. These results suggested that imprinted and non‐imprinted genes and repetitive elements were properly reprogramed during gametogenesis in cloned cattle; therefore, they contributed to the soundness of cloned cattle offspring.  相似文献   
142.
Olive leaf is known to have the high polyphenol content of 6–9% in dry weight. We investigated the effects of olive leaf powder (OLP) supplemented to fish feed on muscle protein of red sea bream (Pagrus major). Fish reared with feed containing 8% OLP for 40 days had 1.4 times higher myofibril content and 2.2 times higher acid-soluble collagen content than fish reared with control feed for the same period. On the other hand, sarcoplasmic protein content and collagenase activity of the muscle were almost the same between the control fish and OLP-diet fish. Microstructure observation of fish muscle showed that OLP-diet fish has more rigid endomysium structure than that of the control-diet fish. Since collagen fiber in endomysium is responsible for the texture of the muscle, feeding OLP to aquaculture fish will lead to a harder muscle texture. The present study suggests that OLP is a useful feed additive to enhance the texture of aquaculture red sea bream muscle through strengthening of the collagen structure in the muscle.  相似文献   
143.
We estimated the genetic parameters of fat‐to‐protein ratio (FPR) and the genetic correlations between FPR and milk yield or somatic cell score in the first three lactations in dairy cows. Data included 3 079 517 test‐day records of 201 138 Holstein cows in Japan from 2006 to 2011. Genetic parameters were estimated with a multiple‐trait random regression model in which the records within and between parities were treated as separate traits. The phenotypic values of FPR increased soon after parturition and peaked at 10 to 20 days in milk, then decreased slowly in mid‐ and late lactation. Heritability estimates for FPR yielded moderate values. Genetic correlations of FPR among parities were low in early lactation. Genetic correlations between FPR and milk yield were positive and low in early lactation, but only in the first lactation. Genetic correlations between FPR and somatic cell score were positive in early lactation and decreased to become negative in mid‐ to late lactation. By using these results for genetic evaluation it should be possible to improve energy balance in dairy cows.  相似文献   
144.
Lectin sensitivity of the recent pandemic influenza A virus (H1N1-2009) was screened for 12 lectins with various carbohydrate specificity by a neutral red dye uptake assay with MDCK cells. Among them, a high mannose (HM)-binding anti-HIV lectin, ESA-2 from the red alga Eucheuma serra, showed the highest inhibition against infection with an EC50 of 12.4 nM. Moreover, ESA-2 exhibited a wide range of antiviral spectrum against various influenza strains with EC50s of pico molar to low nanomolar levels. Besides ESA-2, HM-binding plant lectin ConA, fucose-binding lectins such as fungal AOL from Aspergillus oryzae and AAL from Aleuria aurantia were active against H1N1-2009, but the potency of inhibition was of less magnitude compared with ESA-2. Direct interaction between ESA-2 and a viral envelope glycoprotein, hemagglutinin (HA), was demonstrated by ELISA assay. This interaction was effectively suppressed by glycoproteins bearing HM-glycans, indicating that ESA-2 binds to the HA of influenza virus through HM-glycans. Upon treatment with ESA-2, no viral antigens were detected in the host cells, indicating that ESA-2 inhibited the initial steps of virus entry into the cells. ESA-2 would thus be useful as a novel microbicide to prevent penetration of viruses such as HIV and influenza viruses to the host cells.  相似文献   
145.
Vibrio nigripulchritudo is considered one of the major pathogens threatening shrimp aquaculture. In this study, we developed a novel and highly specific quantitative loop-mediated isothermal amplification (Q-LAMP) assay. A set of four specific primers were designed targeting the V. nigripulchritudo intergenic spacer region. The reaction time and temperature were optimized for 60 min at 63°C. Quantitative analysis was then performed by measuring the turbidity of the reaction solution using a real-time turbidimeter, allowing for quantification of the initial DNA concentration with a sensitivity of 102 copy numbers equivalent to 2.3 colony forming units/ml or 0.3 fg/μl. The LAMP assay was able to specifically detect two representative strains of V. nigripulchritudo, whereas other Vibrio and non-Vibrio species were not amplified. A standard curve was generated for V. nigripulchritudo by plotting the threshold time (T t) versus the log of bacterial number. A high correlation coefficient (R 2 = 0.9749) was observed for the Q-LAMP reaction. In conclusion, Q-LAMP assay is a sensitive, rapid, and simple tool that can be used for the detection and quantification of V. nigripulchritudo in shrimp, thereby facilitating surveillance of vibriosis infection.  相似文献   
146.
147.
OBJECTIVE: To determine the effects of intestinal ischemia and reperfusion on the expression of tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 mRNAs in the jejunum, liver, and lungs of dogs. ANIMALS: 8 healthy adult Beagles. PROCEDURES: In each dog, the cranial mesenteric artery was occluded for 0 (control group; n=4) or 60 (I-R group; 4) minutes, followed by reperfusion for 480 minutes; serum TNF-alpha and IL-6 activities and expression levels of TNF-alpha and IL-6 mRNAs in jejunal, hepatic, and lung tissues were measured before and at the end of the ischemic period and at intervals during reperfusion. For each variable, values were compared between the control and I-R groups at each time point. RESULTS: Compared with the control group, serum IL-6 activity increased significantly after 180 minutes of reperfusion in the I-R group; also, jejunal TNF-alpha mRNA expression increased significantly after 60 (peak) and 180 minutes of reperfusion. In the I-R group, expressions of IL-6 mRNA in the liver and TNF-alpha and IL-6 mRNAs in the lungs increased significantly at 480 minutes of reperfusion, compared with the control group. Serum TNF-alpha activity, expression of IL-6 mRNA in the jejunum, and expression of TNF-alpha mRNA in the liver in the control and I-R groups did not differ. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that the liver, lungs, and jejunum contributed to the production of TNF-alpha and IL-6 after intestinal ischemia and reperfusion in dogs, suggesting that intestinal ischemia and reperfusion induce a systemic proinflammatory cytokine response in dogs.  相似文献   
148.
The causes of early degeneration and calcification of the nucleus pulposus in the chondrodystrophoid dog are poorly understood, and the underlying molecular mechanism of this process has not yet been clearly defined. Type X collagen is one of the key molecules in endochondral bone growth and development, especially matrix calcification. The relationship between type X collagen and disc degeneration and calcification in chondrodystrophoid dogs has not yet been studied. We analyzed the expression of type X collagen in degeneration and calcification of the intervertebral disc in chondrodystrophoid dogs, using type X collagen immunohistochemistry. Control intervertebral discs were collected from five dogs (4 female, 1 male, average age 1.3 years, beagle breed). Degenerated intervertebral discs were surgically removed from 11 canine patients with intervertebral disc extrusion (1 female, 10 male, average age 5.1 years, dachshund breed) in Nippon Veterinary and Animal Science University. All extruded disc samples showed hypertrophic changes and clustering of cells, typical features observed in the degenerated nucleus pulposus. The relative expression of type X collagen in the degenerated nucleus pulposus (84.3 +/- 11.0%) was significantly increased compared to the control nucleus pulposus (5.4 +/- 5.4%). Our findings suggest that type X collagen might contribute to the development of degeneration or calcification in the nucleus pulposus of the chondrodystrophoid dog.  相似文献   
149.
The present study compared responses to selection at different conception rates and litter sizes at weaning in a simulated closed herd in a swine breeding program. The base population consisted of 10 males and 50 females, and 10 generations of selection was practiced by using individual phenotype or best linear unbiased prediction of breeding values for a trait with heritability (h2) of either 0.2 or 0.5. The probability of conception in a single mating was assumed to be 0.8, 0.9 or 1.0. Litter size at weaning was sampled randomly from a normal distribution with mean 8, 10 or 12 and variance 8.1225. Genetic response increased by approximately 6% for h2 = 0.2 and approximately 5% for h2 = 0.5 at generation 10 when conception rate was increased from 0.8 to 1.0. However, litter size at weaning did not affect response to selection. In conclusion, improving conception rate by environmental management increases genetic response indirectly in a breeding program of a closed swine herd.  相似文献   
150.
Three dogs were examined because of episodes of recurrent pruritic dermatitis in the spring, the season of Japanese cedar (Cryptomeria japonica, CJ) pollination in Japan. The dogs were shown to be sensitive to CJ pollen allergen using intradermal testing and antigen-specific IgE measurement. Fluorometric enzyme-linked immunosorbant assay (ELISA) showed increased concentrations of IgE specific to Cry j 1 and a negative result for Cry j 2 in the three dogs. The concentrations of IgE specific to Cry j 1 during the season of CJ pollination were higher than the concentrations found during the off-season in all the dogs, and the variation in the concentrations correlated with the variation in clinical signs. Peripheral blood mononuclear cells showed apparent proliferative responses to crude CJ pollen antigen and Cry j 1 during CJ pollination season. These findings indicated that Cry j 1 was the major allergen recognized by IgE and lymphocytes and resulted in the development of type I hypersensitivity to CJ pollen allergen in these atopic dogs.  相似文献   
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