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Cell cycle analysis of bovine cultured somatic cells by flow cytometry   总被引:1,自引:0,他引:1  
This study was undertaken to examine the cell cycle characteristics of bovine fetal and adult somatic cells (fetal fibroblasts, adult skin and muscle cells, and cumulus cells) after culture under a variety of conditions; 1) growth to 60-70% confluency (cycling), 2) serum starvation, 3) culture to confluency. Cell -cycle phases were determined by flow cytometry with propidium iodide staining enabling the calculation of percentages of cells in G0 /G1, S and G2 /M. The majority was in G0/G1 regardless of cell type and treatment. Serum-starved or confluent cultures contained higher percentages of cells in G0/G1 (89.5-95.4%; P < 0.05). Percentages of cells in G0/G1 increased as cell size decreased regardless of the cell type and treatment. In the serum-starved and confluent cultures, about 98% of small cells were in G0/G1 . Serum-starved cultures contained higher percentages of small cells (38.5-66.9%) than cycling and confluent cultures regardless of cell type (P < 0.05) . After trypsinization of fetal fibroblasts and adult skin cells that were serum-starved and cultured to confluency, the percentages of cells in G0/G1 increased (P < 0.05) on incubation for 1.5 (95.7-99.5%) or 3 hr (95.9-98.6%). These results verify that serum starvation and culture to confluency are efficient means of synchronizing bovine somatic cells in G0/G1, and indicate that a more efficient synchronization of the cells in G0/G1 can be established by incubation for a limited time period after trypsinization of serum-starved or confluent cells.  相似文献   
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We aimed to investigate the effects of inoculating Panax ginseng C.A. Meyer seedlings with arbuscular mycorrhizal fungi (AMF) by examining the root colonization, plant nutrition uptake, growth characteristics, and soil aggregation of P. ginseng seedlings inoculated at the time of transplantation. At 16 weeks, the AMF spore density per 30 g of fresh mycorrhizosphere in seedlings inoculated with AMF (AMF+ seedlings) was 256.8 and that in seedlings not inoculated with AMF (AMF− seedlings) was 186.3, respectively. The colonization rate of AMF in the lateral roots of AMF+ seedlings was approximately 19% higher than that in the lateral roots of AMF− seedlings. The patterns of AMF colonization in ginseng roots were similar to those of the Paris-type mycorrhizal association. Plant growth characteristics, such as plant height, root length, leaf area, number of lateral roots, fresh weight of shoots and roots, and chlorophyll content, were significantly enhanced in AMF+ seedlings compared to AMF− seedlings. The macronutrient content (P, K, and Ca) and micronutrient content (Cu, Fe, and Zn) of both shoots and roots were also significantly higher in AMF+ seedlings compared to AMF− seedlings. Furthermore, glomalin content and soil aggregation were significantly enhanced in AMF inoculated areas. Our results indicate that AMF inoculation may enhance the growth of ginseng seedlings by improving the uptake of mineral nutrients and the soil structure in mycorrhizosphere.  相似文献   
4.
A study was conducted in the USA to determine whether transmissible gastroenteritis (TGE) virus could be transmitted from carcases of slaughtered pigs. Transmissible gastroenteritis virus was transmitted to 6-day-old piglets by dosing with homogenates of muscle and lymph node collected from 500 clinically normal pigs at the time of slaughter. All piglets in 2 separately housed litters showed clinical signs of TGE with 5 piglets dying within 10 d of oral dosing with homogenates. Transmissible gastroenteritis virus was isolated from 2 of these piglets and all piglets developed TGE antibody. Transmissible gastroenteritis virus was not isolated in tissue culture from muscle and lymph node homogenates, but was isolated from 4 (0.8%) of 500 tonsil samples collected from the same pigs. A survey of 250 serum samples provided an estimate of the prevalence of slaughtered pigs with TGE antibody of 34.8% in the sample population. The results indicate that carcases of some pigs from TGE endemic areas contain viable TGE virus, and that there would be a substantial risk of introducing TGE virus into Australia by the importation of uncooked pig meat from these areas.  相似文献   
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Lipid-acyl hydrolases (LAHases) play significant roles in lipid degradation during the storage of vegetables. In particular, spinach contains a large portion of galactolipids (59.5%) and phospholipids (22.4%) among its fat-soluble components, which are used as substrates for LAHases. Thermal inactivation of various LAHases, including phospholipases A, C, and D, phosphatase, and galactolipase, from spinach and carrot was investigated to optimize the blanching process prior to the frozen storage of vegetables. Thermostability of phospholipase C or galactolipase was greatest among the LAHases from both spinach and carrot. Galactolipase from spinach exhibited a D value of 3.39 x 10(2) s at 80 degrees C and a z value of 8.21 degrees C, whereas phospholipase C from spinach showed D(80) of 1.72 x 10(2) s with a z value of 9.26 degrees C. In the case of LAHases from carrot, the D(65) and z values of galactolipase were 6.66 x 10(2) s and 8.69 degrees C, respectively, whereas phospholipase C displayed D(85) of 3.12 x 10(2) s and a z value of 15.8 degrees C. Highly active and thermostable galactolipase and phospholipase C in spinach and carrot made it possible for them to be used as indicator enzymes for the determination of quality deterioration of the stored vegetables.  相似文献   
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By using the leaves with attached intercalary meristems from greenhouse grown stock plants, five cultivars of Cryptanthus were cultured on modified MS media with 4.5 μM NAA and IBA and 3 μM BA to induce adventitious shoot formation from callus tissue. Contamination was 17–21% for explants taken from stock plants which were sprayed weekly with Agribrom and 27–75% for those taken from stock plants which were not treated. More than 99% true to type plantlets were obtained from non-chimeric plants. Green and albino plantlets were obtained from chimeric plants. The chimeric C. ‘Coster's Favorite’ DeCoster also produced a few chimeric plantlets with intermarginal pink stripes in addition to the green and albino plantlets. Most of the non-chimeric plants took a shorter time to produce plantlets of transplantable size (8–12 mm) than the chimeric ones. Except for albino plantlets, survival rate of plantlets exceeded 95%. A minimum average of 500 rooted plantlets can be obtained in a year from a single well-callused leaf explant. The protocol in this report should speed up the mass production and introduction of desirable new cultivars and hybrids of non-chimeric Cryptanthus.  相似文献   
8.
Equine skeletal muscle was histologically and histochemically analyzed in orderto measure fiber composition. Well-sampled open muscle biopsies were obtained from the semitendinosus muscle in select yearling Thoroughbreds. Each biopsy was sectioned and stained for the Harris Hematoxylin and Eosin and the modified Gomori Trichrome in order to demonstrate the basic muscle fiber morphology delineating intra and extracellular elements. A thirdstain, CA++ activated myosin Adenosine Triphosphatase at pH 9.4 was used to differentiate between specific types on the basis of enzyme activities. Subsequent differentiation of Type I slow twitch and Type II fast twitch muscle fibers was assessed on the basisof staining intensity. The high predominance of Type II fast twitch fibers ranged from 85.1 to 100 % with a mean of 90.5 %. Racing records, as two- and three-year-olds, were monitored in order to qualitatively compare histochemical results with performance achievements. While caution must be exercised, results of this investigation suggested that it may be possible, at an early age to partially predict the potential of each horse to adapt to training and to compete successfully in races of varying distances.  相似文献   
9.
The prevalence of anthelmintic resistant nematodes among 52 commercial flocks in south-east England was investigated by comparing the faecal egg counts of groups of lambs before, and seven days after, treatment with thiabendazole and levamisole. Evidence of thiabendazole resistance was found on seven farms. in each case Haemonchus contortus was the only species of nematode involved. In vitro egg hatch assays carried out for isolates from these farms gave ED50 estimates of 0.065 to 0.332 micrograms thiabendazole/ml compared with estimates of 0.027 to 0.031 micrograms thiabendazole/ml for a known susceptible strain of H contortus assayed at the same time. In a series of slaughter trials, there was a 17 to 85 per cent reduction, as compared with controls, in the mean worm burdens of groups of lambs infected with these isolates and killed seven days after treatment with thiabendazole, confirming their resistance to this anthelmintic.  相似文献   
10.
A PVYO virus-resistant potato (Solanum tuberosum L. cv. Golden Valley) was identified, and further, from its tubers, a small (5.57 kDa) antiviral peptide potide-G was isolated. Application of potide-G on virus susceptible potato (cv. Winter valley) expressed robust resistance to PVYO infection and showed no virus infected morphology. We found that PVYO infection spreads up completely within 3 days post inoculation (dpi) in susceptible cultivar. PVYO was more accumulated toward the basal leaves, when infection occurred longer. Combined results of morphology of PVYO infection, ELISA, RT-PCR, and real-time PCR showed the resistance to the PVYO infection depends on the expression of Ry gene. Indeed, the real-time PCR result showed that the Ry gene up-regulated to 3 times higher in PVYO infected cv. Golden valley. Golden crude protein was found to be active against PVYO infection in the in vivo test. In addition, application of potide-G in a virus susceptible potato potently reduced the viral infection actively with 50 times lower concentration than that of the Golden protein. Further identification of a host-specific resistant gene in a plant and the peptide derived from it offers new opportunities for the development of novel bio-pesticides against plant virus.  相似文献   
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