小鼠体内卵母细胞死亡的形态变化研究

目前大多数研究主要是针对体外的卵母细胞凋亡,并且通常采用抗癌试剂来人为的引入。然而,对体内卵母细胞死亡的过程还不是很明确。为了查明体内未受精卵的死亡过程,我们检测了从输卵管壶腹部冲出的注射了HCG后不同间隔的卵母细胞中的细胞化学物质的改变情况。在每一个收集的时间段,在显微镜下将收集的卵母细胞从表观上分成四组:单细胞卵母细胞(没有激活和没有核或胞浆移动),激活的卵母细胞(带有核的单细胞,2-或4-细胞),碎裂的卵母细胞及其死亡的卵母细胞。随着时间的推移,单细胞卵母细胞的数量下降,死亡的卵母细胞数量增加,但是激活或碎裂的卵母细胞数量未发生改变。同时,检测到的大多数死亡的卵母细胞都是单细胞。在每一个时间点上,用抗微管蛋白抗体对单细胞卵母细胞进行着色,来检测它们的纺锤体状态。在注射HCG24h之后,大多数超排后的卵母细胞都有两极纺锤体,然而在超排后64h的单细胞卵母细胞就没有纺锤体。结果表明,大多数的体内卵母细胞在单细胞期就出现死亡,而激活或碎裂的卵母细胞则不是。     

Collagen complexes increase the efficiency of iPS cells generated using fibroblasts from adult mice

Different interventions are being tested for restoration of the youthfulness of adult mouse-derived fibroblasts. However, fundamental issues, such as the decline of adult mouse-derived fibroblast activity with age, remain unresolved. Therefore, in this study, we examined whether treatment with collagen complexes has beneficial effects on the rejuvenation or reprogramming of adult mouse-derived fibroblasts. Further, we investigated the mechanisms of rejuvenation of adult mouse-derived fibroblasts during treatment with total collagen complexes. We isolated total collagen complexes from the tails of young mice and cultured adult mouse-derived fibroblasts with or without the collagen complexes. When compared with fibroblasts cultured without collagen complexes, adult-derived fibroblasts cultured with collagen complexes over five consecutive passages showed a more youthful state, expanded at a higher rate, and exhibited reduced spontaneous cell death. The fibroblasts cultured in the presence of collagen complexes also showed extensive demethylation in the promoter regions of cell cycle-related genes such as PCNA, increased proliferation, and decreased senescence. In addition, the efficiency of reprogramming of fibroblasts to become induced pluripotent stem (iPS) cells was significantly higher in young- and adult-derived fibroblasts cultured with collagen complexes than in adult-derived fibroblasts cultured alone. Furthermore, mechanistic evidence shows that genes involved in anti-proliferative pathways, including Ink4a/Arf locus genes and p53, were downregulated in fibroblasts exposed to collagen complexes. Interestingly, our results suggest that the rejuvenation process was mediated via the α2β1 integrin-dependent Bmi-1 pathway. Thus, collagen complexes both stimulate proliferation and inhibit cell death and growth arrest in fibroblasts, which appears to be a promising approach for improving the efficiency of reprogramming.     

Comparative Analysis of the Total Factor Productivity of Manufacturing in Northeast Asian Metropolitan Areas

We compare and analyze the total factor productivity of the manufacturing industries in the major metropolitan areas of South Korea, China, and Japan. This study can contribute to the economic cooperation among these countries by analyzing their productivity growth and evaluating their relative competitiveness. Statistical data from manufacturing industries are used to analyze five metropolitan areas. The manufacturing industries are classified into 10 sectors, and two different time periods (before and after 1997, when the foreign currency crisis began in Korea) are examined. The results in terms of the development and competitiveness of the manufacturing industries in Korea, China, and Japan will be useful in establishing promotional strategies.     

粳稻“龙锦1号/香软米1578” F3家系群糙米矿质元素含量变异及相关性分析

 利用粳稻品种间杂交组合“龙锦1号/香软米1578”的196份F3家系,对糙米中Fe、Se、Zn、Cu、Mn、Ca、Mg、K、Na和P等10种矿质元素含量的变异及其相关性进行了分析。 10种矿质元素在F3家系间均有较大的变异,其中Na含量变异最大,Zn含量变异最小,变异系数分别为77.69％和12.04％。各矿质元素含量的变异系数大小顺序为Na>Se>Cu>Fe>Mg>Mn>Ca>P>K>Zn。不同矿质元素含量也有较大的差异,F3家系群各矿质元素含量平均值高低排序为P>K>Mg>Ca>Fe>Mn>Zn>Na>Cu>Se。糙米中10种矿质元素含量在F3家系群中均表现为正态分布,为由多基因控制的数量性状。Zn与Fe、Cu,Mn与Mg、Ca、K、P,Ca与Mg、K、Na、P,Mg与K、P,P与K、Na含量呈显著或极显著正相关,而Fe与Se、Mn与Na、Mg与Na含量呈显著或极显著负相关。Mn、Ca、Mg、K、P含量与其他矿质元素含量间的相关关系较Fe、Se、Cu、Zn含量与其他矿质元素含量间的相关关系更为密切。     

Evaluation of ruminal motility using an indwelling 3-axis accelerometer in the reticulum in cattle

Attempts to increase production and improve farm environments have been made for several years. Rumen motility (RM) is one of the biological parameters that provides essential information of individuals in ruminants, and it is usually evaluated by auscultation. The study was aimed to examine RM using the 3-axis accelerometer (3XA) in cattle. The manufactured 3XA were placed in the reticulum (3XA-R) and implanted in the subcutaneous layer of the brisket (3XA-SC), respectively, and the accelerations were compared following intramuscular injection of xylazine (0.05 mg/kg) or saline in experiment 1 and of xylazine (0.05 mg/kg) or atropine (0.04 mg/kg) in experiment 2. In experiment 3, the dose-dependent decrease of RM was evaluated following xylazine administration (0, 0.05, 0.1 mg/kg) in the 3XA-R equipped cows via a 3 × 3 Latin square method. In experiment 1, saline-treated animals showed a continuous fluctuation while the frequency and amplitude of 3XA-R in xylazine-injected cows were reduced after administration. The acceleration of 3XA-SC was changed after administration, but not abruptly. Among the motion parameters, V2 was calculated only using X- and Z-axis acceleration in consideration of the cylindrical shape, and it showed the apparent difference between pre- and post-xylazine administration. In experiment 2, the V2 of 3XA-R was decreased after atropine administration while that of 3XA-SC was maintained. In experiment 3, a dose-dependent V2 decrement of 3XA-R after xylazine administration was observed and lasted for 40 and 80 min in doses of 0.05 mg/kg and 0.1 mg/kg, respectively. In conclusion, The 3XA detected the decrease in RM efficiently and processed the data wirelessly without interference from body movement. This technology will help detect problems early and prevent a decline in cattle productivity.     

ULTRASOUND‐GUIDED MESENTERIC LYMPH NODE IOHEXOL INJECTION FOR THORACIC DUCT COMPUTED TOMOGRAPHIC LYMPHOGRAPHY IN CATS

Computed tomographic (CT) lymphography was performed in cats using percutaneous ultrasound‐guided injection of contrast medium into a mesenteric lymph node. The thoracic duct and its branches were clearly delineated in CT images of seven cats studied. The thoracic duct was characterized by anatomic variation and appeared as single or multiple branches. The thoracic duct and the cisterna chyli were identified along the ventral or left ventral aspect of the vertebrae from the level of the cranial lumbar to the caudal cervical vertebrae. The thoracic duct was identified in the central caudal mediastinum, deviated to the left in the cranial mediastinum, and finally moved toward the venous system. Small volumes of extranodal contrast medium leakage were identified in all cats. After injection, the mesenteric lymph nodes were cytologically normal. Ultrasound‐guided CT lymphography via percutaneous mesenteric lymph node injection appears safe and effective in cats.     

Influence of Catalyst Thickness on Diameters of Carbon Nanotubes

Owing to unique structure and characteristic of carbon nanotubes, much more are attracted attentions since they were discovered .In recent years, carbon nanotubes have been successfully synthesized by various methods. Especially, highly aligned carbon nanotubes were grown by chemical vapor deposition (CVD). In the work, it is studied that different thickness of catalyst affects the diameters of carbon nanotubes. Carbon nanotubes were grown on silicon substrate coated with different thick NiFe films by bias-enhanced hot filament chemical vapor deposition and their growth was investigated by scanning electron microscopy,Onset of analyzing of deformation of different thick catalyst films during heating the filament. The results indicate that catalyst particles encapsulate the top ends of carbon nanotubes, and that the catalyst thickness greatly affects the diameters of carbon nanotubes, which increas with increment of the thickness of NiFe films.     

Effect of 7,8-Dihydroxyflavone as an Antioxidant on In Vitro Maturation of Oocytes and Development of Parthenogenetic Embryos in Pigs

One of the factors that impairs in vitro produced porcine embryosis the oxidative stress that is mainly caused by the imbalance between reactiveoxygen species (ROS) generation and antioxidants activity, especially that ofglutathione (GSH). Here, we examined the effect of 7,8-dihydroxyflavone (7,8-DHF), akind of flavonoid antioxidant, on porcine oocyte maturation and its developmentalcompetence. Porcine oocytes were cultured in media supplemented with 0, 1, 5 and 10μM 7,8-DHF during both in vitro maturation (IVM) and invitro culture (IVC) after parthenogenetic activation. Maturation ofoocytes was evaluated based on first polar body (PB) extrusion and intracellular GSHlevel, and developmental competence was assessed through observing cleavage andblastocyst formation. In each step, the levels of intracellular GSH and ROS wereassessed by fluorescence intensity, and the apoptosis-related gene expression wasexamined using semiquantitative RT-PCR. The group treated with 1 μM 7,8-DHF duringIVM and IVC showed increased cytoplasmic maturation and reached the blastocysts stage(36.1%) at a higher rate than the other groups (24.7, 16.0 and 10.3% for 0, 5 and 10μM, P<0.05). In that group, the intracellular GSH level was significantlyincreased while ROS generation was significantly decreased after IVM and IVC(P<0.05). Moreover, it showed high expression of an anti-apoptotic gene(BCL2L1) and low expression of a pro-apoptotic gene(BAK1) (P<0.05). In conclusion, treatment with 1 μM 7,8-DHFduring IVM and IVC showed an anti-apoptotic effect by increasing intracellular GSHsynthesis and scavenging ROS and therefore improved the developmental competence ofporcine embryos.     

Surveillance of classical swine fever in wild boar in South Korea from 2010–2014

Classical swine fever (CSF) is a highly contagious systemic hemorrhagic viral disease of pigs. Wild boar plays a crucial role in the epidemiology of CSF. Between 2010 and 2014, samples were collected nationwide from 6,654 wild boars hunted in South Korea. Anti-CSF antibodies were identified in 0.59% (39 of 6,654) of the wild boar samples using a virus neutralization test and were primarily detected in wild boars living close to the demilitarized zone and the area of the Taebaek Mountains surroundings. The CSF virus (subgroup 2.1b) was isolated from two wild boars captured in a nearby border area. The criteria used to define high-risk areas for targeted CSF surveillance in South Korea should be further expanded to include other regions nationwide.