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101.
Background
Recent studies have assessed the therapeutic potential and drawbacks of mesenchymal stem cells (MSCs). The adverse reactions of intravenous transplantation of bone marrow (BM)-derived MSCs were examined at varying doses and frequencies of administration.Nine healthy beagle dogs were purchased from a commercial laboratory. The dogs were distributed equally (n = 3 per group) and randomly into three groups. All dogs received allogeneic BM-derived MSCs: 2 × 106 once (group A), 2 × 107 once (group B), and 2 × 106 for three consecutive days (group C). Various laboratory examinations, multi-detector computed tomography features and histopathology were evaluated to clarify the clinical and diagnostic features of adverse reactions of MSCs administration, prior to receiving MSCs (pre procedure) and on days 1, 3, and 7 post transplantation.Results
Only one dog had clinical signs during and after MSCs transplantation. Dogs receiving 2 × 106 MSCs showed increased numbers of lymphocytes but the total white blood cell counts were not elevated (P < 0.01). Multi-detector computed tomography (MDCT) revealed pulmonary parenchymal changes in one dog and histopathologic examination revealed pulmonary parenchymal edema and hemorrhage in four dogs. The presence of pulmonary thromboembolism was not detected in either examination.Conclusions
We considered the presence of pulmonary edema and hemorrhage as possible adverse reactions after intravenous MSCs transplantation; however these results should be cautiously interpreted. 相似文献102.
103.
JI Yun HJ Park MH Park MS Kim JH Choi E Lee SP Gong JM Lim ST Lee 《Reproduction in domestic animals》2014,49(5):705-710
Recently, isolation and in vitro culture of putative spermatogonial stem cells (SSCs) in the domestic cat have been conducted. However, the cellular niche conditions that facilitate the establishment and long‐term maintenance of feline SSCs (FSSCs) have not been described. Therefore, we investigated the type of feeder cells used to stimulate colony formation and growth of FSSCs among the various factors in the FSSC niche. Spermatogonial stem cells isolated from feline testes were cultured on mitotically inactivated testicular stromal cells (TSCs) derived from cats, dogs and mice, and mouse embryonic fibroblasts (MEFs). The formation and growth of colonies derived from SSCs cultured on each type of feeder cell were identified at passage 0, and the morphology, alkaline phosphatase (AP) activity and expression of SSC‐specific genes in surviving colonies were investigated at passage 4. Among these diverse feeder cells, TSCs from cat showed the greatest colony formation, growth and maintenance of FSSCs, and SSC colonies cultured by passage 4 showed a typical dome‐shaped morphology, AP activity and expression of SSC‐specific genes (NANOG, OCT4, SOX2 and CD9). Accordingly, these results demonstrate that feline TSCs could be used as feeder cells to support the establishment and maintenance of SSCs from domestic cats. 相似文献
104.
Sang-Bum Park Min Lee Dong-Won Son Sang-Min Lee Jong-In Kim 《Journal of Wood Science》2014,60(1):74-79
Authors established a new manufacturing technology for crack-free carbonized boards by pressing and carbonizing the medium-density fiberboard. Industrialization of new functional carbon materials was performed by investigating the fundamental properties of the carbonized boards. To be used as a construction material, the carbonized board needs to satisfy the fire performance regulation. In this study, the carbonized boards were manufactured from medium-density fiberboard (c-MDF) at different temperatures and then fire performance including flame retardancy and smoke toxicity was analyzed using a cone calorimeter and noxious gas analyzer. The results show that as the carbonization temperature increases, weight loss ratio decreases and flame retardancy increases. In the c-MDF at 800 and 1000 °C, no external damage was observed after combustion. These c-MDFs satisfy the total heat release (standard below 8 MJ/m2) and heat release rate (standard below 200 kW/m2) regulations according to the Building Standard Law of Korea and Japan. In addition, the c-MDFs showed the lower total smoke release (TSR, 0.213 m2/m2) than that of virgin MDF (94.281 m2/m2). The c-MDF at 800 and 1000 °C were, therefore, classified as a class III flame retardancy material and can be used as indoor finishing material. 相似文献
105.
Jong-Hak Yun Katsuhiro Nakao Ikutaro Tsuyama Motoki Higa Tetsuya Matsui Chan-Ho Park Byoung-Yoon Lee Nobuyuki Tanaka 《Journal of Forest Research》2014,19(1):174-183
To quantitatively assess future change of evergreen broad-leaved tree species’ distributions in human-disturbed landscapes of the Korean Peninsula under climate change, potential habitats (PHs) were projected for four important evergreen broad-leaved tree species (Quercus acuta, Castanopsis sieboldii, Machilus thunbergii, and Neolitsea sericea) by species distribution models (SDMs). The distribution data (presence/absence) of the target species in Korea and Japan were used as response variables for SDMs, and climatic data were used as explanatory variables. Three general circulation models under A2 emission scenarios were used as future climate scenarios for the years 2070–2099. Potential habitats masked by land-use data (PHLUs) were projected to assess the impact of anthropogenic activities. Highly accurate SDMs were obtained for all the target species. The current PHs were decreased to 21–35 % by the anthropogenic activities. Future PHLUs for all the target species were projected to increase by 2.0–18.5 times of current PHLUs. These results suggest that all the target species are applicable as indicator species for monitoring in the Korean Peninsula, even if anthropogenic effects are incorporated. Variation of the increasing rate was caused by the differences in the response to temperature changes. M. thunbergii responded sensitively to the increase of minimum temperature of coldest month and had a largest increase in PHLUs under future climate. Therefore, M. thunbergii is considered to be most appropriate species for monitoring the changes of horizontal distributions above all focal evergreen broad-leaved tree species. 相似文献
106.
The spined soldier bug, Podisus maculiventris (Say), is a generalist predator that can control >75 insect pests in various agroecosystems. Despite valuable results from the previous studies, thermal development and survival of P. maculiventris over a wide range of temperatures had not been elucidated completely. This study was conducted to investigate the stage-specific development and survival of P. maculiventris at eight constant temperatures (13.2, 18.4, 21.7, 23.7, 27.2, 32.7, 35.2, and 40.6 °C) covering the entire thermal range for P. maculiventris development. Completion of egg development was observed at 13.2–32.7 °C, whereas nymphs successfully developed into adults at 18.4–32.7 °C. Survival model using log-normal equations showed bell-shape patterns for all stages, and temperatures resulting in highest survival of P. maculiventris were 19.9, 24.3, and 24.5 °C for egg, nymph, and egg to adult, respectively. Developmental rates at the eight temperatures were fitted with a nonlinear Briere model, which estimated optimal temperatures for development as 31.2, 30.6, and 30.6 °C for egg, nymph, and egg to adult, respectively. Operative thermal ranges (i.e., in-between the lower and upper developmental thresholds) were estimated to be 8.9–35.2, 12.8–35.2, and 12.7–35.2 °C for egg, nymph, and egg to adult, respectively. In a linear model, the lower thresholds were 10.9, 13.1, and 13.0 °C for egg, nymph, and egg to adult, respectively. Findings herein provide comprehensive data and explanations on optimal temperature and thermal requirement for P. maculiventris, which can be used to optimize environmental condition in mass rearing and predicting phenology of P. maculiventris in the field. 相似文献
107.
In this study, fully vitellogenic oocytes of the longchin goby (Chasmichthys dolichognathus) were exposed to in vitro xenoestrogens such as diethylstilbestrol (DES), bisphenol A (BPA) and nonylphenol (NP) at concentrations of 100 ng/ml in the presence of [3H]17α-hydroxyprogesterone as precursor. The major metabolites produced in vitro are progestogens [17α-hydroxy,20α-dihydroprogesterone (17α20αOHP) and 17α-hydroxy,20β-dihydroprogesterone (17α20βOHP)], androgens [androstenedione (A4) and testosterone (T)] and estrogens [estrone (E1) and estradiol-17β (E2)]. Comparative activities of these chemicals in oocyte steroid biosynthesis showed as follows: NP treatment resulted in clear stimulation of estrogen production, while the opposite occurred in DES treated incubation. Treatment with DES resulted in a higher synthesis of 17α20αOHP. BPA treatment increased the androgen, while estrogen synthesis was slightly inhibited. These results suggest that NP exhibited clearly estrogenic activity on the three chemicals. 相似文献
108.
Distribution of free L-cysteine and glutathione in seaweeds 总被引:1,自引:0,他引:1
109.
110.
Ji Hyeon Ahn Joon Ha Park In Hye Kim Jae-Chul Lee Bing Chun Yan Min Sik Yong Choong Hyun Lee Jung Hoon Choi Ki-Yeon Yoo In Koo Hwang Seung Myung Moon Hyung-Cheul Shin Moo-Ho Won 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(3):335-342
Melatonin affects diverse physiological functions through its receptor and plays an important role in the central nervous system. In the present study, we compared immunoreactivity patterns of arylalkylamine N-acetyltransferase (AANAT), an enzyme essential for melatonin synthesis, and melatonin receptor type 1B (MT2) in the spinal cord of young adult (2~3 years) and aged (10~12 years) beagle dogs using immunohistochemistry and Western blotting. AANAT-specific immunoreactivity was observed in the nuclei of spinal neurons, and was significantly increased in aged dog spinal neurons compared to young adult spinal neurons. MT2-specific immunoreactivity was found in the cytoplasm of spinal neurons, and was predominantly increased in the margin of the neuron cytoplasm in aged spinal cord compared to that in the young adult dogs. These increased levels of AANAT and MT2 immunoreactivity in aged spinal cord might be a feature of normal aging and associated with a feedback mechanism that compensates for decreased production of melatonin during aging. 相似文献