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51.
52.
A method of reliably producing developmentally competent cat embryos in vitro is a prerequisite for study of the physiology of early development and application of assisted reproductive techniques. Oocytes were collected and then cultured in TCM-199 + 10% FBS for 4 h. The matured oocytes were activated with a 20 microsec electric pulse at 1.2 kV/mm. The activated oocytes were incubated in 2 mM of 6-dimethylaminopurine (6-DMAP) for 4 h and were then divided randomly among the treatment groups. In experiment 1, we compared the effects of three culture systems (TCM-199, CR1-aa and Tyrode's) on the in vitro development of parthenogenetically activated cat oocytes. In experiment 2, we investigated the effect of addition of Iloprost (a stable prostaglandin I(2) analogue) to Tyrode's medium on in vitro development of parthenogenetically activated oocytes. As a control, we recovered in vivo produced blastocysts and determined their average cell number. In experiment 1, the cleavage frequency of the oocytes cultured in TCM199, CR1-aa and Tyrode's media were similar (74, 72 and 83%, respectively). However, the incidence of in vitro development to the blastocyst stage was significantly higher in Tyrode's medium (20.4%) than in TCM-199 (2.4%) or CR1-aa (11.1%). Likewise, the average cell number of in vitro activated blastocysts was higher in Tyrode's than in CR1-aa or TCM-199 (106.5 +/- 45.2 vs. 68.3 +/- 25.4 and 35.0 +/- 7.7, respectively; P<0.05). In experiment 2, the percentage of parthenogenetically activated oocytes that underwent in vitro blastocyst development was significantly improved by addition of Iloprost to the culture medium (33.6 vs. 19.1%; P<0.05). The average cell number of in vivo blastocysts (909.0 +/- 226.4) was significantly higher than those of in vitro blastocysts cultured in Tyrode's medium supplemented with or without Iloprost (103.2 +/- 31.3 and 112.2 +/- 39.3, respectively; P<0.05). This result indicated that the current culture method for cat pathogenetically activated oocytes requires further improvement. 相似文献
53.
Pharmacokinetics of amoxicillin trihydrate in cultured olive flounder (Paralichthys olivaceus) 下载免费PDF全文
J. S. Seo E. J. Jeon S. H. Jung M. A. Park N. Y. Kim 《Journal of veterinary pharmacology and therapeutics》2015,38(1):86-92
The study was aimed at investigating the pharmacokinetics of amoxicillin trihydrate (AMOX) in olive flounder (Paralichthys olivaceus) following oral, intramuscular, and intravenous administration, using high‐performance liquid chromatography following. The maximum plasma concentration (Cmax), following oral administration of 40 and 80 mg/kg body weight (b.w.), AMOX was 1.14 (Tmax, 1.7 h) and 0.76 μg/mL (Tmax, 1.6 h), respectively. Intramuscular administration of 30 and 60 mg/kg of AMOX resulted in Cmax values of 4 and 4.3 μg/mL, respectively, with the corresponding Tmax values of 29 and 38 h. Intravenous administration of 6 mg/kg AMOX resulted in a Cmax of 9 μg/mL 2 h after administration. Following oral administration of 40 and 80 mg/kg AMOX, area under the curve (AUC) values were 52.257 and 41.219 μg/mL·h, respectively. Intramuscular 30 and 60 mg/kg doses resulted in AUC values of 370.274 and 453.655 μg/mL·h, respectively, while the AUC following intravenous administration was 86.274 μg/mL·h. AMOX bioavailability was calculated to be 9% and 3.6% following oral administration of 40 and 80 mg/kg, respectively, and the corresponding values following intramuscular administration were 86% and 53%. In conclusion, this study demonstrated high bioavailability of AMOX following oral administration in olive flounder. 相似文献
54.
MEASUREMENTS OF THE PULMONARY VASCULATURE ON THORACIC RADIOGRAPHS IN HEALTHY DOGS COMPARED TO DOGS WITH MITRAL REGURGITATION 下载免费PDF全文
Heejin Oui Juyeon Oh Seoyeon Keh Gahyun Lee Sunghoon Jeon Hyunwook Kim Junghee Yoon Jihye Choi 《Veterinary radiology & ultrasound》2015,56(3):251-256
This study reassessed the previously reported radiographic method of comparing pulmonary vessels versus rib diameter for differentiating healthy dogs and dogs with mitral regurgitation. The width of the right cranial pulmonary artery and vein at the fourth rib level, right caudal pulmonary artery and vein at the ninth rib level, and the diameters of the fourth rib and ninth rib were measured in prospectively recruited healthy dogs (n = 40) and retrospectively recruited dogs with mitral regurgitation (n = 58). In healthy dogs, the pulmonary arteries and accompanying veins were similar in size. The cranial lobar vessels were smaller than the fourth rib. However, 67.5% of right caudal pulmonary artery diameters and 65% of vein diameters were larger than the ninth rib in healthy dogs. The right caudal pulmonary vein diameter in dogs with mitral regurgitation, particularly those within moderate and severe grades, was significantly larger than that in healthy dogs (P < 0.001). The comparative method used to detect enlargement of the right caudal pulmonary vein relative to the accompanying pulmonary artery had the highest sensitivity (80.2%) and specificity (82.5%) for predicting mitral regurgitation. A cut‐off of 1.22 when applying the ninth rib criterion had better specificity (73%) than the most used value ≤ 1 (89.7% sensitivity and 63.8% specificity), although it has less sensitivity (73%). We recommend using the accompanying pulmonary artery and 1.22 × the diameter of the ninth rib as a radiographic criterion for assessing the size of the right caudal pulmonary vein and differentiating healthy dogs from those with mitral regurgitation. 相似文献
55.
Min Jae Kim Tae Hwan Oh Sung Soo Han Sang Woo Joo Han Yong Jeon Dong Wook Chang 《Fibers and Polymers》2014,15(1):101-107
Poly(vinyl alcohol) (PVA)/Ag-zeolite nanocomposite hydrogels were prepared by UV irradiation using PVA solution mixed with Ag-zeolite nanoparticles. Physical properties and changes in morphology of the PVA/Ag-zeolite hydrogels were investigated. The PVA/Ag-zeolite hydrogels were prepared at a PVA concentration of 9 wt% with a UV irradiation distance of 15 cm, where gel fraction and swelling ratio were optimized. Hardness of the PVA/Ag-zeolite hydrogels decreased with increasing amounts of Ag-zeolite, reaching that of soft elastomer when the amount of Ag-zeolite was 5 % by weight. The PVA/Ag-zeolite hydrogels showed strong antimicrobial activities against Staphylococcus aureus and Klebsiella pneumoniae, inducing a reduction of bacteria of over 99.9 % at a Ag-zeolite content of 3 wt%. 相似文献
56.
Van-Tinh Nguyen Jung Suck Lee Zhong-Ji Qian Yong-Xin Li Kil-Nam Kim Soo-Jin Heo You-Jin Jeon Won Sun Park Il-Whan Choi Jae-Young Je Won-Kyo Jung 《Marine drugs》2014,12(1):69-87
Gliotoxin, a secondary metabolite produced by marine fungus Aspergillus sp., possesses various biological activities including anticancer activity. However, the mechanism underlying gliotoxin-induced cytotoxicity on human cervical cancer (Hela) and human chondrosarcoma (SW1353) cells remains unclear. In this study, we focused on the effect of gliotoxin induction on apoptosis, the activating expressions of caspase family enzymes in the cells. Apoptotic cell levels were measured through DAPI and Annexin V/Propidium Iodide (PI) double staining analysis. The apoptotic protein expression of Bcl-2 and caspase family was detected by Western blot in Hela and SW1353 cells. Our results showed that gliotoxin treatment inhibited cell proliferation and induced significant morphological changes. Gliotoxin induced apoptosis was further confirmed by DNA fragmentation, chromatin condensation and disrupted mitochondrial membrane potential. Gliotoxin-induced activation of caspase-3, caspase-8 and caspase-9, down-regulation of Bcl-2, up-regulation of Bax and cytochromec (cyt c) release showed evidence for the gliotoxin activity on apoptosis. These findings suggest that gliotoxin isolated from marine fungus Aspergillus sp. induced apoptosis in Hela and SW1353 cells via the mitochondrial pathway followed by downstream events leading to apoptotic mode of cell death. 相似文献
57.
Development of cellular dependence on infective organisms: micrurgical studies in amoebas 总被引:6,自引:0,他引:6
K W Jeon 《Science (New York, N.Y.)》1972,176(39):1122-1123
Nuclei and cytoplasm were transferred between a normal strain anda variant strain of Amoeba discoides heavily infected with bacteria. After 5 years of infection, the infective bacteria that were initially harmful to the host cells became harmless, and the nucleus of the host cell became dependent on the infective organisms for its normal functions. 相似文献
58.
Short wool fibers obtained by the stretch breaking process can be blended with cotton fibers and processed in a cotton spinning
system, which has a high production rate. For the structural property of the wool fiber after stretch breaking, the diameter
and length of the wool fiber were measured as a function of time. The diameter of the broken fibers was finer than the diameter
of untreated fibers. The fiber diameter at the break point was the finest and was more irregular than the original fiber.
The broken fiber showed mechanical properties of increased modulus, decreased breaking strain, and increased breaking strength. 相似文献
59.
Karki R Sahi N Jeon ER Park YS Kim DW 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(1):27-33
Oxidation susceptibility of serum lipid and the proliferation and migration of vascular smooth muscle cells (VSMC) from tunica
media to the sub endothelial region are the key steps in the progression of atherosclerosis. The objective of this study was
to determine the effects of Chungtaejeon (CTJ) on oxidation and cytokine induced proliferation and migration of human aortic
smooth muscle cells (HASMC). The antioxidative effects of CTJ were evaluated by using 1,1-diphenyl-2-picryl hydrazyl (DPPH)
scavenging assay, nitric oxide (NO) scavenging assay and thiobarbituric acid reactive substance (TBARS) assay. Similarly,
the proliferation, migration and expression of matrix metalloproteinases (MMPs) in HASMC were assessed by MTT assay, transwell
Boyden chamber assay and gelatin zymography, respectively. Western blotting was done to determine the protein expression of
MMP-9, phospho extracellular regulated kinase (pERK1/2) and phospho c-Jun N-terminal kinase (pJNK). In results, the IC50 values for DPPH and NO scavenging activities were 8.91 μg/ml and 14.32 μg/ml, respectively. Furthermore, CTJ inhibited TBARS
formation dose dependently. The pretreatment of CTJ dose dependently inhibited the tumor necrosis factor-α (TNF-α) induced
proliferation and MMP-9 expression and platelet derived growth factor (PDGF) induced migration of HASMC. Thus, CTJ can be
suggested to have beneficial effect in the prevention of atherosclerosis. 相似文献
60.
A hilly to mountainous watershed in Chonju in central Korea does not receive acid rain (average pH: 6.2); however, the stream water in the granite watershed is slightly acidic (6.4–6.7) and contains a low concentration of Ca compared to the stream water in sedimentary and volcanic rock watersheds (6.8–7.6). Although the concentrations of Ca and Sr and the 87Sr/86Sr ratio in the stream water change in accordance with the watershed geology, the stream 87Sr/86Sr ratios are closer to the 87Sr/86Sr ratios of rain than to those of the substrate rocks, suggesting the selective but sluggish weathering of Ca-containing minerals neutralizes acid. The concentrations of trace metals (As, Cr, Cu, Mo, Ni, Pb) in the water are lower than those in rain and less dependent on the watershed geology, indicating that they originated dominantly from the atmosphere. This result is consistent with the stream water having Pb isotope ratios close to that of rain but distinct from that of the rocks. We assume that the soil pool of exchangeable ions dominantly contains atmospherically derived heavy metals, which are subsequently discharged into streams. It is likely that the poor acid-neutralizing capacity of granite makes the aquatic systems in the granite watershed in Chonju sensitive to atmospheric acidification. 相似文献