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11.
M. Podojil P. Sedmera J. Vokoun V. Betina H. Baráthová Z. Ďuračková K. Horáková P. Nemec 《Folia microbiologica》1978,23(6):438-443
Eurotium repens mycelium cultivated under static conditions was used to isolate and identify metabolities—echinulin, physcion, erythroglaucin,
flavoglaucin and asperentin; the filtrate of the culture yielded asperentin 8-methylether. The broadest biological activity
spectrum was displayed by asperentin which had antibacterial and antifungal effects and, at a concentration of 86 ώg/ml, caused
50 % mor7 tality inArtemia saline larvae. The highest cytotoxicity towards HeLa cells was found in physcion which caused 50 % growth inhibition at a concentration
of 0.1 ώg/ml. 相似文献
12.
L. Hess M. Votava J. Schreiberová J. Málek M. Horáček 《Journal of medical primatology》2010,39(3):151-159
Background The aim of the study was to compare the effect of naphthylmedetomidine to medetomidine on the behavior of orangutans and chimpanzees. Methods The immobilization was performed as part of a medical examination in five chimpanzees and three orangutans. Following pre‐medication with midazolam (0.70–1.20 mg/kg p.o.), naphthylmedetomidine (50–70 μg/kg), or medetomidine (20–30 μg/kg) was given with ketamine (3 mg/kg) and hyaluronidase (150 M.U.) into musculus deltoideus. Results We observed the distinct anti‐aggressive effect of naphthylmedetomidine. The immobilization with naphthylmedetomidine was shallower and the influence on cardiac frequency less substantial compared to medetomidine. The overall sedative effect of naphthylmedetomidine lasted for less time, and its effect was incompletely antagonized with atipamezole in comparison to medetomidine. Conclusions Naphthylmedetomidine could replace medetomidine for inducing immobilization and sedation. A combination of naphthylmedetomidine–ketamine is suitable for relocating animals to other cages or for painless medical examinations. 相似文献
13.
Bor Luen Tang 《Journal of cellular physiology》2013,228(5):915-916
A process of unconventional secretion that is dependent on the Golgi stacking protein GRASP and multiple components of the autophagy machinery has recently been documented for several cytoplasmic and membrane protein. Classical secretion via the exocytic pathway is inhibited during cell division in animal cells, as key membrane compartments, particularly the Golgi, are disassembled and fragmented. The question as to whether unconventional secretion is likewise inhibited during mitosis has not been explored. This mode of secretion supposedly bypasses the Golgi. However, GRASP and Vps34 (a key autophagy protein) are both substrates of the cell cycle regulating cyclin‐dependent kinase 1 (Cdk1), and their activities are apparently inhibited by Cdk1 phosphorylation. Is unconventional secretion therefore similarly inhibited during cell division like conventional secretion? The story may yet turn out to be more complicated. J. Cell. Physiol. © 2012 Wiley Periodicals, Inc. 相似文献
14.
In the present study, the cytoarchitectonic structure of the nuclei of the mamillary body has been studied on 4 age groups of Merino sheep and the following has been found: There is a significant intraspecific variability in the construction of mamillary body. Some of the animals studied have odd others paired mamillary bodies. Variability has been stated in the formation of the medial mamillary nucleus. The topographical relation of the mamillary nuclei to other hypothalamic structures during postnatal development did not change. Only the rostro-caudal length of the nuclei could be examined as changed. The quantity of Nissl substance increased in the cells of both mamillary nuclei studied which is related to maturation of the animals. Increased amounts of glial cells were observed during the postnatal period. 相似文献
15.
V Seliger V Novotny M Mácek O Skranc J Horák J Piric P Handzo J Rous Z Jirka J Parízková L Vank 《European journal of applied physiology and occupational physiology》1978,39(3):165-171
A total of 3762 subjects of both sexes, natives of Czechoslovakia, ranging in age from 12--55 years, were examined. Both anamnestic data and selected anthropometric variables were evaluated. The proportion of non-smokers for adult males was 47--56%, and for adult females was 54--74% of the population. The proportion of subjects not engaged in any type of physical activity decreases in boys between 12 and 18 years from 28 to 16%, in girls between 12 and 15 years from 25 to 22%; from then on the trend reverses and the percentages rises up to 42% in men and 65% in women. The number of subjects participating in competitive sporting activity reaches its peak at 18 years, when 46% of boys annd 43% of girls compete, but then decreases quickly. 12 year old girls are taller and heavier than boys but at 15 years the relationship is reversed. The LBM at the age of 12 is equal in boys and girls, but from then till 18 years the increase is larger in boys. The LBM weight in adults remains steady, women attaining 77% of the value found in men. The skinfold increases with age similarly in both sexes, except for an interval between 12 and 18 years, when girls show a steeper increase. Adult women attain 121--160% of the values characteristic for men. The grip strength of the right hand equals about 50 kp in adult men and 30 kp in adult women. Within the age range followed, it remains unaffected by age. 相似文献
16.
Ptáková Michaela Pokorný Petr Šída Petr Novák Jan Horáček Ivan Juřičková Lucie Meduna Petr Bezděk Aleš Myšková Eva Walls Matthew Poschlod Peter 《Vegetation History and Archaeobotany》2021,30(2):269-286
Vegetation History and Archaeobotany - In a continuous, perfectly stratified sedimentary sequence which was discovered under a large sandstone overhang in northern Bohemia, Czech Republic, we... 相似文献
17.
Tsai‐Ching Hsu Chun‐Ching Chiu Yi‐Wen Wang Bor‐Show Tzang 《Journal of cellular and molecular medicine》2013,17(10):1308-1315
Attenuated antioxidant activities, irregular cytokines expressions and reduced regulatory T cells, are strongly associated with the pathogenesis of systemic lupus erythematosus (SLE). Despite the well‐established beneficial effects of cystamine on lupus‐prone mice, the extent to which cystamine contributes to antioxidant activity and the reduction of regulatory T cells has seldom been investigated. Therefore, this study elucidates how cystamine affects anti‐oxidant activities in NZB/W F1 mice by performing assays of Glutathione (GSH), 1,1‐diphenyl‐2‐ picryl‐hydrazyl (DPPH) and malondialdehyde thiobarbituric acid (MDA). In addition, investigations of the effects of cystamine on CD4+/CD25+ regulatory T cells and interleukin‐6 (IL6)/STAT‐3 signalling were performed with flow cytometry and immunoblots. Experimental results reveal more significantly reduced MDA and increased GSH and DPPH in NZB/W F1 mice receiving cystamine than in those mice receiving PBS. Meanwhile, CD4+/CD25+ regulatory T cells more significantly increase in NZB/W F1 mice receiving cystamine than in those mice receiving PBS, accompanied by significantly reduced IL‐6/phosphorylated STAT‐3 expression. The above findings suggest the beneficial effects of cystamine in terms of increasing antioxidant activities and CD4+/CD25+ regulatory T cells in lupus‐prone mice by suppressing IL‐6/STAT3 signalling. 相似文献
18.
19.
Yuki Ito Jose Luis Vela Fumiko Matsumura Hitomi Hoshino Aaron Tyznik Heeseob Lee Enrico Girardi Dirk M. Zajonc Robert Liddington Motohiro Kobayashi Xingfeng Bao Jeanna Bugaytsova Thomas Borén Rongsheng Jin Yinong Zong Peter H. Seeberger Jun Nakayama Mitchell Kronenberg Minoru Fukuda 《PloS one》2013,8(12)
Approximately 10–15% of individuals infected with Helicobacter pylori will develop ulcer disease (gastric or duodenal ulcer), while most people infected with H. pylori will be asymptomatic. The majority of infected individuals remain asymptomatic partly due to the inhibition of synthesis of cholesteryl α-glucosides in H. pylori cell wall by α1,4-GlcNAc-capped mucin O-glycans, which are expressed in the deeper portion of gastric mucosa. However, it has not been determined how cholesteryl α-glucosyltransferase (αCgT), which forms cholesteryl α-glucosides, functions in the pathogenesis of H. pylori infection. Here, we show that the activity of αCgT from H. pylori clinical isolates is highly correlated with the degree of gastric atrophy. We investigated the role of cholesteryl α-glucosides in various aspects of the immune response. Phagocytosis and activation of dendritic cells were observed at similar degrees in the presence of wild-type H. pylori or variants harboring mutant forms of αCgT showing a range of enzymatic activity. However, cholesteryl α-glucosides were recognized by invariant natural killer T (iNKT) cells, eliciting an immune response in vitro and in vivo. Following inoculation of H. pylori harboring highly active αCgT into iNKT cell-deficient (Jα18−/−) or wild-type mice, bacterial recovery significantly increased in Jα18−/− compared to wild-type mice. Moreover, cytokine production characteristic of Th1 and Th2 cells dramatically decreased in Jα18−/− compared to wild-type mice. These findings demonstrate that cholesteryl α-glucosides play critical roles in H. pylori-mediated gastric inflammation and precancerous atrophic gastritis. 相似文献
20.
Bor Luen Tang 《Journal of cellular physiology》2020,235(11):7653-7662
Prolonged survival of a typical postmitotic neuron hinges on a balance between multiple processes, among these are a sustenance of ATP production and protection against reactive oxygen species. In neuropathological conditions, mitochondrial defects often lead to both a drop in ATP levels, as well as increase reactive oxygen species production from inefficient electron transport processes and NADPH-oxidases activities. The former often resulted in the phenomenon of compensatory aerobic glycolysis. The latter stretches the capacity of the cell's redox buffering capacity, and may lead to damages of key enzymes involved in energy metabolism. Several recent reports have indicated that enhancing glucose availability and uptake, as well as increasing glycolytic flux via pharmacological or genetic manipulation of glycolytic enzymes, could be protective in animal models of several major neurodegenerative diseases, including Parkinson's disease, Huntington's disease, and Amyotrophic lateral sclerosis. Activation of canonical Wnt signaling, which improves disease symptoms in mouse models of Alzheimer's disease also appears to work via an elevation of glycolytic enzymes and enhance glucose metabolism. Here, I discuss these findings and the possible underlying mechanisms of how an increase in glucose uptake and glycolysis could be neuroprotective. Increased glycolytic production of ATP would help alleviate energy deficiency, and ATP's hydrotropic effect may enhance solubility and clearance of toxic aggregates prevalent in many neurodegenerative diseases. Furthermore, channeling of glucose into the Pentose Phosphate Pathway would increase the redox buffering capacity of the cell. 相似文献