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951.
Yang BC Lee SH Hwang S Lee HC Im GS Kim DH Lee DK Lee KT Jeon IS Oh SJ Park SB 《BMB reports》2012,45(1):38-43
We investigated phenotypic differences in Hanwoo cattle cloned from somatic cells of a single adult. Ten genetically identical Hanwoo were generated by somatic cell nuclear transfer from a single adult. Weights at birth, growing pattern, horn and noseprint patterns were characterized to investigate phenotypic differences. The weights of clones at 6 and 12 months were slightly heavier than that of the donor. A horn pattern analysis revealed that seven clones had exactly the same horn pattern as the donor cow, whereas three were different. Although similarities such as general appearance can often be used to identify individual cloned animals, no study has characterized noseprint patterns for this end. A noseprint pattern analysis of all surviving clones showed that all eight animals had distinct noseprints. Four were similar to the donor, and the remaining four had more secondary-like characteristics. 相似文献
952.
Joon Ki Hong Jihyun Je Chieun Song Jung Eun Hwang Yeon-Hee Lee Chae Oh Lim 《Genes & genomics.》2012,34(1):13-18
The phytocystatins are inhibitors of papain-like cysteine proteinases that are implicated in defense mechanisms and the regulation of protein turnover. BCPI-1, a Brassica rapa (Chinese cabbage) phytocystatin isolated from flower buds, contains an extended C-terminal region that contains a single Cys residue at position 102. In an effort to investigate the role of the C-terminus and this Cys residue in BCPI-1 activity, purified recombinant proteins of BCPI-1, including wild-type BCPI-1 (wtBCPI-1), N-terminus BCPI-1 (BCPI-1??C), C-terminus BCPI-1 (BCPI-1??N), and BCPI-1 with a single Cys residue exchange to Ser (BCPI-1C102S), were generated and their inhibitory activities against papain were investigated. Kinetic analysis revealed that the monomeric forms of wtBCPI-1 (K i = 6.84 ± 0.3 × 10?8 M) inhibited papain more efficiently than the dimeric forms of wtBCPI-1 (K i = 1.01 ± 0.5 × 10?7 M). Experiments with recombinant BCPI-1C102S demonstrated that the dimerization of wtBCPI-1 caused by the formation of an intermolecular disulfide bond at the cysteine residue. The inhibitory activity of the recombinant proteins, except BCPI-1??N, was reduced in the pH range of 7.0?C11.5 and was highly stable over a wide range of temperatures. Thus, dimerization mediated by the cysteine residue in the extended C-terminal region and alkaline conditions reduced the inhibitory activity of BCPI-1. 相似文献
953.
JY Jung IY Kim YN Kim JS Kim JH Shin ZH Jang HS Lee GS Hwang JK Seong 《BMB reports》2012,45(7):419-424
High-fat diets (HFD) and high-carbohydrate diets (HCD)- induced obesity through different pathways, but the metabolic differences between these diets are not fully understood. Therefore, we applied proton nuclear magnetic resonance ((1)H NMR)-based metabolomics to compare the metabolic patterns between C57BL/6 mice fed HCD and those fed HFD. Principal component analysis derived from (1)H NMR spectra of urine showed a clear separation between the HCD and HFD groups. Based on the changes in urinary metabolites, the slow rate of weight gain in mice fed the HCD related to activation of the tricarboxylic acid cycle (resulting in increased levels of citrate and succinate in HCD mice), while the HFD affected nicotinamide metabolism (increased levels of 1-methylnicotineamide, nicotinamide-N-oxide in HFD mice), which leads to systemic oxidative stress. In addition, perturbation of gut microflora metabolism was also related to different metabolic patterns of those two diets. These findings demonstrate that (1)H NMR-based metabolomics can identify diet-dependent perturbations in biological pathways. 相似文献
954.
JS Goo MK Jang SB Shim SW Jee SH Lee CJ Bae S Park KJ Kim JE Kim IS Hwang HR Lee SI Choi YJ Lee CJ Lim DY Hwang 《Laboratory animal research》2012,28(2):141-145
The drug resistance of microorganisms isolated from laboratory animals never treated with antibiotics is being reported consistently, while the number of laboratory animals used in medicine, pharmacy, veterinary medicine, agriculture, nutrition, and environmental and health science has increased rapidly in Korea. Therefore, this study examined the development of antimicrobial resistance in bacteria isolated from laboratory animals bred in Korea. A total of 443 isolates (7 species) containing 5 Sphingomonas paucimobilis, 206 Escherichia coli, 60 Staphylococcus aureus, 15 Staphylococcus epidermidis, 77 Enterococcus faecalis, 27 Citrobacter freundii, 35 Acinetobacter baumannii were collected from the nose, intestine, bronchus and reproductive organs of ICR mice and SD rats. Of these species, Acinetobacter baumannii and Enterococcus faecalis showed significant antimicrobial resistance according to the minimum inhibition concentration (MIC) in E-test. In case of Acinetobacter baumannii, several isolates showed MIC values 16-128 μg/mL for cefazolin and cefoxitin, and higher resistance (128-512 μg/mL) to nitrofurantoin than that of standard type. Resistance to cefazolin, cefoxitin and nitrofurantoin was detected in 17.14, 20.00, and 8.57% of the Acinetobacter baumannii isolates, respectively. In addition, 44.1% of the Enterococcus faecalis isolates collected from the laboratory animals were resistant to oxacillin concentration of 16-32 μg/mL range, while MIC value of standard type was below oxacillin concentration of 6 μg/mL. These results suggest that in rodent species of laboratory animals, Acinetobacter baumannii are resistance to cefazolin, cefoxitin and nitrofurantoin, whereas those of Enterococcus faecalis were resistance to oxacillin. 相似文献
955.
HR Lee IS Hwang JE Kim SI Choi YJ Lee JS Goo EP Lee HW Choi HS Kim JH Lee YJ Jung DY Hwang 《Laboratory animal research》2012,28(2):109-114
Altered expression of neurotrophic factors as well as neuroinflammation is commonly associated with Major depressive disorder (MDD) and Alzheimer's disease (AD). To investigate whether or not reserpine-induced MDD affects the expression of AD-related proteins, the expression of γ-secretase components and substrate were measured in brains of ICR mice following reserpine treatment for 15 days. In active avoidance test, total response time and peak slightly increased in the 2 mg/kg reserpine (RSP2)-treated group compared to vehicle-treated group (P<0.05). Expression and phosphorylation of MKP-1, which is a key factor in MDD pathology, were both higher in the RSP2-treated group than the vehicle- and 1 mg/kg reserpine (RSP1)-treated groups (P<0.02). Furthermore, full-length expression of amyloid precursor protein (APP) was enhanced in the RSP1 and RSP2-treated groups compared to the vehicle-treated group, whereas expression of γ-secretase components decreased (P<0.03). Among the three components of the γ-secretase complex, nicastrin protein underwent the largest decrease in expression, as detected by Western blotting (P<0.03). Therefore, the data presented here provide additional evidence about the pathological correlation between MDD and AD. 相似文献
956.
The effects of polarized-light therapy (PLT) on high-cholesterol diet (HCD)-induced hypercholesterolemia and atherosclerosis were investigated in comparison with that of lovastatin in rabbits. Hypercholesterolemia was induced by feeding male New Zealand white rabbits with 1% cholesterol in diet for 2 weeks and maintained with 0.5% cholesterol for 6 weeks, followed by normal diet for 2 weeks for recovery. Lovastatin (0.002% in diet) or daily 5-min or 20-min PLT on the outside surface of ears was started 2 weeks after induction of hypercholesterolemia. Hypercholesterolemic rabbits exhibited great increases in serum cholesterol and low-density lipoproteins (LDL) levels, and finally severe atheromatous plaques formation covering 57.5% of the arterial walls. Lovastatin markedly reduced both the cholesterol and LDL, but the reducing effect (47.5%) on atheroma formation was relatively low. By comparison, 5-min PLT preferentially decreased LDL, rather than cholesterol, and thereby potentially reduced the atheroma area to 42.2%. Notably, 20-min PLT was superior to lovastatin in reducing both the cholesterol and LDL levels as well as the atheromatous plaque formation (26.4%). In contrast to the increases in blood alanine transaminase and aspartate transaminase following lovastatin treatment, PLT did not cause hepatotoxicity. In addition, PLT decreased platelets and hematocrit level. The results indicate that PLT attenuates atherosclerosis not only by lowering blood cholesterol and LDL levels, but also by improving blood flow without adverse effects. Therefore, it is suggested that PLT could be a safe alternative therapy for the improvement of hypercholesterolemia and atherosclerosis. 相似文献
957.
In this paper we report about 88 longhorned beetles (Cerambycidae) species found in 6929 hectares and distributed along an altitudinal gradient of 1500 m of an Italian alpine valley (Val Genova, central-eastern Italian Alps). The species richness, result merging data from sixty years (1947-2007) of entomological surveys, corresponds to the 32% of the Italian cerambycid fauna confirming the high richness/surface ratio, probably unique in the Alps. The effect of thirteen environmental variables was tested on the species richness, but only the elevation resulted able to affect it. The species richness decrease with altitude not gradually, but experience a strong step above 1700 m a.s.l.. The highest species richness (average values of 42 species) was recorded at the lowest and mid elevations (between 800 and 1600 m a.s.l.). The species turnover along the altitudinal gradient is low suggesting moderate habitat turnover along the valley.One of the eighty-eight observed species, Tragosoma depsarium,is classified near threatened by the IUCN. Our data suggest that the wilderness of the valley close to the suitable management of grasslands and forests, help to support high level of cerambycids diversity. This biodiversity is good indicators of health of the wood saproxylic assemblages, as well an important food source for many vertebrate predators. 相似文献
958.
Lee CW Hwang I Park CS Lee H Park DW Kang SJ Lee SW Kim YH Park SW Park SJ 《Biomarkers》2012,17(3):209-215
We analyzed the innate immunity markers, C-reactive protein (CRP), serum amyloid P component (SAP) and pentraxin-3 (PTX-3), and metalloproteinase-9 (MMP-9) in coronary atherectomy tissues obtained from patients with acute ST elevation myocardial infarction (STEMI) (n=27) or stable angina (n=15). The relative areas immunopositive for CRP and SAP were similar in the two groups. In contrast, the proportion of areas immunopositive for PTX-3 and MMP-9 was higher in the STEMI group, compared to the stable angina group. PTX-3 or MMP-9-stained areas largely overlapped with those positive for CD68. We concluded that PTX-3 plays a role in the pathogenesis of STEMI. 相似文献
959.
Bustamante-Marín X Quiroga C Lavandero S Reyes JG Moreno RD 《Apoptosis : an international journal on programmed cell death》2012,17(6):539-550
Apoptosis, necrosis and autophagy are mechanistically related processes that control tissue homeostasis and cell survival.
In the testis, germ cell death is important for controlling sperm output, but it is unknown whether or not germ cells can
switch from apoptosis to necrosis, as has been reported in other tissues. Furthermore, autophagy has not been reported in
spermatogenesis. Spermatocytes (meiotic cells) and spermatids (haploid cells) use lactate rather than glucose as their primary
substrate for producing ATP. The metabolism of glucose, but not lactate, reduces ATP levels and increases intracellular [H+] and [Ca2+], both of which are associated with apoptosis and/or necrosis in somatic cells. In this work, we evaluated whether different
energy sources, such as lactate or glucose, can influence spermatocyte death type and/or survival in primary cultures. Spermatocytes
cultured for 12 h without an energy source died by necrosis, while spermatocytes cultured with 5 mM glucose showed a significant
increase in apoptosis, as evidenced by caspase activity, TUNEL assay and phosphatidylserine exposure. Apoptosis was not observed
in spermatocytes cultured with 5 mM lactate or deoxyglucose. Authophagy markers, such as LC3-II and autophagosomes, were detected
after 12 h of culture, regardless the culture conditions. These results suggest that the availability of glucose and/or lactate
affect the type of death or the survival of primary spermatocytes, where glucose can induce apoptosis, while lactate is a
protective factor. 相似文献
960.
Hee-Jin Jeong Jin-Kyung Kwon Devendra Pandeya JeeNa Hwang Ngoc Huy Hoang Joong-Hwan Bae Byoung-Cheorl Kang 《Molecular breeding : new strategies in plant improvement》2012,29(2):349-360
Allele mining is a method used to find undiscovered natural variations or induced mutations in a plant, and has become increasingly
important as more genomic information is available in plants. A high-throughput method is required to facilitate the identification
of novel alleles in a large number of samples. In this paper we describe the application of a high-resolution melting (HRM)
method to detect natural variations and ethyl methane sulfonate (EMS)-induced mutations in Capsicum. We have scanned single polymorphic mutations in the first exon of the eIF4E gene, wherein the mutations confer resistance to potyviruses. Sixteen allelic variations out of 248 germplasm collections
were identified using HRM analysis, and one accession carrying an allelic variation (pvrHRM1
13
) was confirmed to be resistant to the TEV-HAT strain. In addition, five single polymorphic mutations in the eIF4E gene were identified in an EMS-induced mutant population. These results demonstrate that HRM allows for the rapid identification
of new allelic variants in both natural and artificial mutant populations. 相似文献