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For investigating the effects of physiologically relevant heat shock, buffalo oocytes/embryos were cultured at 38.5°C (control) or were exposed to 39.5°C (Group II) or 40.5°C (Group III) for 2 h once every day throughout in vitro maturation (IVM), fertilization (IVF) and culture (IVC). Percentage of oocytes that developed to 8‐cell, 16‐cell or blastocyst stage was lower (p < 0.05) and the number of apoptotic nuclei was higher (p < 0.05) for Group III > Group II > controls. At both 8–16‐cell and blastocyst stages, relative mRNA abundance of stress‐related genes HSP 70.1 and HSP 70.2 and pro‐apoptotic genes CASPASE‐3, BID and BAX was higher (p < 0.05) in Groups III and II than that in controls with the exception of stress‐related gene HSF1. Expression level of anti‐apoptotic genes BCL‐XL and MCL‐1 was also higher (p < 0.05) in Groups III and II than that in controls at both 8–16‐cell and blastocyst stages. Among the genes related to embryonic development, at 8–16‐cell stage, the expression level of GDF9 was higher (p < 0.05) in Group III than that in controls, whereas that of GLUT1, ZAR1 and BMP15 was not significantly different among the three groups. At the blastocyst stage, relative mRNA abundance of GLUT1 and GDF9 was higher (p < 0.05) in Group II than that in controls, whereas that of ZAR‐1 and BMP15 was not affected. The results of this study demonstrate that exposure of buffalo oocytes and embryos to elevated temperatures for duration of time that is physiologically relevant severely compromises their developmental competence, increases apoptosis and affects stress‐, apoptosis‐ and development‐related genes.  相似文献   
33.
When buffalo embryonic stem (ES) cell–like cells that expressed surface markers SSEA‐4, TRA‐1‐60, TRA‐1‐81, CD9 and CD90 and intracellular markers OCT4, SOX2 and FOXD3, as shown by immunofluorescence, and that expressed REX‐1 and NUCLEOSTEMIN as confirmed by RT‐PCR, were subjected to suspension culture in hanging drops in absence of LIF and buffalo foetal fibroblast feeder layer support, they differentiated to form three‐dimensional embryoid bodies (EBs). Of 231 EBs examined on Day 3 of suspension culture, 141 (61.3 ± 3.09%) were of compact type, whereas 90 (38.4 ± 3.12%) were of cystic type. The cells obtained from EBs were found to express NF‐68 and NESTIN (ectodermal lineage), BMP‐4 and α‐skeletal actin (mesodermal lineage), and α‐fetoprotein, GATA‐4 and HNF‐4 (endodermal lineage). When these EBs were cultured on gelatin‐coated dishes, they spontaneously differentiated to several cell types such as epithelial‐ and neuron‐like cells. When EBs were cultured in the presence of 1 or 2% DMSO or 10?8 m or 10?7 m retinoic acid for 25 days, ES cells could be directed to form muscle cell–like cells, the identity of which was confirmed by expression of α‐actinin by immunofluorescence and of MYF‐5, MYOD and MYOGENIN genes by RT‐PCR. MYOD was first detected on Day 10 in both treatment groups and on Day 15 in controls, whereas MYOGENIN was first detected on Day 10, Day 15 and Day 25 in the presence of retinoic acid, in the presence of DMSO and in controls, respectively. The present study demonstrates the ability of buffalo ES cell–like cells to undergo directed differentiation to cells of skeletal myogenic lineage.  相似文献   
34.
The aim of this study was to develop a radiographic standard for the assessment of pulmonary fluid clearance and lung aeration in newborn calves. Caesarean‐delivered mature calves (= 9) underwent lung assessment by thoracic radiography as well as arterial and venous blood gas analysis within the first 30 min, 1, 2, 3, 6, 12 and 24 hr after birth. The results indicated that newborn calves delivered by elective Caesarean section suffered from a physiological combined respiratory and metabolic acidosis with the dominance of respiratory acidosis, and an improvement in these conditions was recorded within 24 hr after birth. Concerning the radiographic results, clear lung fields, improvement in lung expansion, air content of the lung and absence of lung opacification occurred within 24 hr of birth. Furthermore, the ventral lung quadrant showed an improvement in radiographic opacification and lung expansion earlier than the dorsal lung regions. The findings of this study support the potential role of thoracic radiography in the assessment of pulmonary fluid clearance and lung aeration in newborn calves.  相似文献   
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An unusual outbreak of contagious ovine ecthyma   总被引:1,自引:0,他引:1  
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38.
Pathologic findings in manatees in Florida   总被引:1,自引:0,他引:1  
Necropsy and microscopic examinations of 16 West Indian manatees (Trichechus manatus) revealed that the mortality of many of the animals was associated with environmental factors such as human-inflicted trauma and cold winters. Natural disease processes accounted for the death of only 1 manatee. In 3 manatees, the cause of death could not be determined.  相似文献   
39.
Peronospora radii de Bary 1863, a new record in Israel, was found in January 1985 to be the cause of a downy mildew of cultivated marguerite daisies, cv. ‘Scheine von Nizza’ (a cultivar ofArgyranthemum frutescens: Anthemideae: Compositae), grown in an unheated greenhouse in the Coastal Plain. The same fungal species was found in February 1986 on the very common, wildChrysanthemum coronarium (Anthemideae), 13 km distant from the previous year’s location. Conidia of the fungus on ‘Nizza’ leaves had average dimensions similar to those on ‘Nizza’ flowers, but differed in variance (minimal and maximal length and width) and 40% of them had papillate apicesvs 4% in conidia from flowers. The average length and width of conidia from both leaves and flowers of ‘Nizza’ were slightly above those already described forP. radii in the literature. The conidia fromCh. coronarium had average lengths, widths and quotients significantly higher than those from ‘Nizza’ and from the previously published data, extending the range to 43.8 x 24.3 μm, quotient: 1.83vs the highest published averages of 34.2 x 23.74 μm, quotient: 1.70. OnCh. coronarium, the dimensions of conidia had great variance within samples from the same plant and differed significantly even between plants at the same time and location, showing this fungus to have more variability than was previously known. Oospores, known elsewhere for this species, were not found in Israel. The disease was successfully transmitted from diseasedCh. coronarium to healthyCh. coronarium and ‘Nizza’(A. frutescens) but not to another, white-flowered cultivar ofA. frutescens, when all these different plants were transplanted and grown together in physical contact. Isozyme analysis, performed on conidial samples ofP. radii from leaves of both species of hosts and flowers ofCh. coronarium, corroborated that the pathogen was the same on each host and on both petals and leaves. The disease was eradicated by chemical treatment in the commercial greenhouse and also disappeared without treatment in infected plants kept over summer in a dry, airconditioned glasshouse.  相似文献   
40.
The State of Kuwait has initiated an ambitious national program to establish greenery in 20000 ha of open spaces in inland and coastal areas. Afforestation of intertidal zones with mangrove plants is being considered as a viable option for greening coastal areas. In view of this fact, experimental plantations were established using two ecotypes of Avicennia marina (Bahrain and UAE) and one ecotype of Avicennia germinans (Florida). The study consisted of two 10-year old plantations and two 2-year old plantations. Seedlings established successfully and grew vigorously on some of the locations within the site. Therefore, studies were conducted during 2002-2003 to describe and classify soils that supported maximum mangrove establishment and growth under the harsh arid coastal conditions of Kuwait. For this purpose, eight soil profiles (four each representing areas where seedlings established successfully and grew vigorously and where all seedlings died in the initial stages of establishment) were investigated and classified according to the soil taxonomy. The main soil types observed in the study site were: Typic Aquisalids, Typic/sodic Aquicambids and Calcic Aquisalids. Mangrove growth performance in relation to the landform, soil type and properties of the soil at various depths is discussed in the paper. The plant growth appeared to be the better on the typic Aquisalid soil than that on the Typic/sodic Aquicambid soils. The relative proportions of the coarse sand fraction, occurrence of the anaerobic layer in the profile and the surface layer salinity influenced both the establishment and growth of mangrove plants.  相似文献   
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