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991.
992.
BackgroundMany herbal medicines are traditionally used as anti-fatigue agents in east Asian countries; however, there is a dearth of clinical evidence supporting the anti-fatigue effects of such medicines and their mechanisms. This study is a feasibility trial to assess the clinical efficacy of Gongjin-dan (GJD) and verify its mechanisms by exploring fatigue outcomes, including endocrine and immunological biomarkers in humans.Methods/DesignTo investigate the anti-fatigue effects of GJD and the mechanism underlying these effects, a randomised, double-blind, placebo-controlled crossover clinical trial was designed. Participants (24 healthy male volunteers) will be hospitalised for 4 days (3 nights), during which acute fatigue and stress conditions will be induced by sleep deprivation, and GJD or a placebo will be administered (twice daily). The primary outcome will be changes in serum cortisol levels, measured in the morning, as an objective biomarker of sleep deprivation-induced fatigue and stress. The secondary outcomes will include: the Fatigue Severity Scale; the Brief Fatigue Inventory, and the Leeds Sleep Evaluation Questionnaire scores; levels of salivary cortisol, epinephrine, norepinephrine, oxidative stress-related biomarkers, homocysteine, and immunological factors; and heart rate variability. After a washout period of more than 4 weeks, a second treatment phase will commence in which participants who were previously administered the placebo will receive the drug and vice versa, following the same treatment regime as in the first phase.DiscussionThis study protocol provides a unique opportunity to enhance our understanding of fatigue and the effects of GJD on fatigue in terms of endocrine and immunological mechanisms by validating the study design and determining feasibility. Findings from this trial will help researchers to design a pilot or definitive clinical trial of traditional herbal medicine for chronic fatigue.
Trial registration
Korean National Clinical Trial Registry CRIS; KCT0001681, registered on 29 October 2015. 相似文献993.
Feeding and oviposition preference of the Sakhalin pine sawyer Monochamus saltuarius (Coleoptera: Cerambycidae) for various tree species
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Monochamus saltuarius was recently identified as an important vector of Bursaphelenchus xylophilus, the cause of pine wilt disease. In this study, M. saltuarius adults preferred different species of tree based on the longevity, ingested amount and wounded area that were determined for 90 d. Among eight tree species, the longevity of feeding by M. saltuarius was not significantly different except when feeding in Sciadopitys verticillata. However, the highest ingested amounts with the largest wounded areas were associated with Pinus koraiensis. The highest oviposition preference was in P. densiflora for the first 20 d. However, after 40 d, the oviposition highest preference was noted in P. koraiensis. For oviposition activities, M. saltuarius preferred the tree species in the following order: P. densiflora > P. koraiensis > P. rigida > Larix leptolepis. Although many oviposition scars were observed, M. saltuarius laid fewer eggs in P. rigida than other species of pine, which was related to the bark thickness. The oviposition frequencies were highest with bark 2.0–2.5 mm thick and with tree diameters of 110–130 mm. The current study increased understanding of the ecology of M. saltuarius by identifying specific tree preferences. 相似文献
994.
The importance of H2S in biology and medicine has been widely recognized in recent years, and protein S-sulfhydration is proposed to mediate the direct actions of H2S bioactivity in the body. Thioredoxin 1 (Trx1) is an important reducing enzyme that cleaves disulfides in proteins and acts as an S-denitrosylase. The regulation of Trx1 on protein S-sulfhydration is unclear. Here we showed that Trx1 facilitates protein S-desulfhydration. Overexpression of Trx1 attenuated the basal level and H2S-induced protein S-sulfhydration by direct interaction with S-sulfhydrated proteins, i.e., glyceraldehyde 3-phosphate dehydrogenase and pyruvate carboxylase. In contrast, knockdown of Trx1 mRNA expression by short interfering RNA or blockage of Trx1 redox activity with PX12 or 2,4-dinitrochlorobenzene enhanced protein S-sulfhydration. Mutation of cysteine-32 but not cysteine-35 in the Trp–Cys32–Gly–Pro–Cys35 motif eliminated the binding of Trx1 with S-sulfhydrated proteins and abolished the S-desulfhydrating effect of Trx1. All these data suggest that Trx1 acts as an S-desulfhydrase. 相似文献
995.
Hyeon‐Ki Jang Byung‐Soo Kim Jin Han Jeong‐Kee Yoon Ju‐Ro Lee Gun‐Jae Jeong Jung‐Youn Shin 《Biotechnology progress》2016,32(2):456-464
Stem cell‐conditioned medium (CM), which contains angiogenic factors that are secreted by stem cells, represents a potential therapy for ischemic diseases. Along with stem cells, tumor cells also secrete various angiogenic factors. Here, tumor cells as a cell source of CM for therapeutic angiogenesis was evaluated and the therapeutic efficacy of tumor cell CM in mouse hindlimb ischemia models was demonstrated. CM obtained from a human fibrosarcoma HT1080 cell line culture was compared with CM obtained from a human bone marrow‐derived mesenchymal stem cell (MSC) culture. HT1080 CM contained higher concentrations of angiogenic factors compared with MSC CM, which was attributable to the higher cell density that resulted from a much faster growth rate of HT1080 cells compared with MSCs. For use in in vitro and in vivo angiogenesis studies, HT1080 CM was diluted such that HT1080 CM and MSC CM would have the same cell number basis. The two types of CMs induced the same extent of human umbilical vein endothelial cell (HUVEC) proliferation in vitro. The injection of HT1080 CM into mouse ischemic limbs significantly improved capillary density and blood perfusion compared with the injection of fresh medium. Although the therapeutic outcome of HT1080 CM was similar to that of MSC CM, the preparation of CM by tumor cell line culture would be much more efficient due to the faster growth and unlimited life‐time of the tumor cell line. These data suggest the potential application of tumor cell CM as a therapeutic modality for angiogenesis and ischemic diseases. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:456–464, 2016 相似文献
996.
Yun Hee Kim Dong Hyun Kim Eun Jung Shin Hyun Ju Lee Won Ryang Wee Saewha Jeon Mee Kum Kim 《PloS one》2016,11(1)
Purpose
To compare the regenerative potential of cultured oral mucosal epithelial cells sheets (COMECs) from Stevens-Johnson syndrome (SJS) subjects with those from non-SJS subjects.Methods
Human oral mucosal epithelial cells from SJS and non-SJS subjects were cultured, and colony-forming efficiency (CFE), proliferative and migration potential, expression of cytokines/growth factors and stem cells were compared. COMECs from SJS and non-SJS subjects were transplanted into 12 limbal stem cell-deficient rabbits, and their regenerative potential was analyzed at 1 week after transplantation.Results
CFE (p>0.05, student’s t test), cell proliferation potential (p>0.05, two-way ANOVA) and expression of the cytokeratins (K3, K4, K13, K19) in the oral mucosal epithelial cells from SJS subjects were similar to those of the cells from non-SJS subjects. The initial migratory potential of SJS cells was delayed compared to that of non-SJS cells (p <0.05, RM two-way ANOVA). The SJS cells expressed lower levels of EGF and higher levels of VEGF compared to that of non-SJS cells (p<0.05, one-way ANOVA). In vivo transplanted SJS-COMECs showed similar expression of K3, K4, and K13, proliferation markers (Ki-67; p>0.05, Mann-Whitney U test), and stem cell markers (p63; p>0.05, Mann-Whitney U test) compared to non-SJS COMECs. The initial epithelial defects in vivo were larger in the eyes treated with SJS-COMECs on day 3 (p<0.01, RM two-way ANOVA), but no differences were observed by day 7 between SJS- and non-SJS-COMECs.Conclusions
These results suggest that, aside from differences in migratory potential, oral mucosal epithelial cells from SJS and non-SJS subjects are comparable in their regeneration potential in treating limbal stem cell deficiency. 相似文献997.
Guang‐Xin E Tao Zhong Yue‐Hui Ma Hui‐Jiang Gao Jian‐Ning He Nan Liu Yong‐Ju Zhao Jia‐Hua Zhang Yong‐Fu Huang 《Ecology and evolution》2016,6(3):810-817
The domestic sheep (Ovis aries) has been an economically and culturally important farm animal species since its domestication around the world. A wide array of sheep breeds with abundant phenotypic diversity exists including domestication and selection as well as the indigenous breeds may harbor specific features as a result of adaptation to their environment. The objective of this study was to investigate the population structure of indigenous sheep in a large geographic location of the Chinese mainland. Six microsatellites were genotyped for 611 individuals from 14 populations. The mean number of alleles (±SD) ranged from 7.00 ± 3.69 in Gangba sheep to 10.50 ± 4.23 in Tibetan sheep. The observed heterozygote frequency (±SD) within a population ranged from 0.58 ± 0.03 in Gangba sheep to 0.71 ± 0.03 in Zazakh sheep and Minxian black fur sheep. In addition, there was a low pairwise difference among the Minxian black fur sheep, Mongolian sheep, Gansu alpine merino, and Lanzhou fat‐tailed sheep. Bayesian analysis with the program STRUCTURE showed support for 3 clusters, revealing a vague genetic clustering pattern with geographic location. The results of the current study inferred high genetic diversity within these native sheep in the Chinese mainland. 相似文献
998.
P Juárez R R Brenner 《Comparative biochemistry and physiology. B, Comparative biochemistry》1989,93(4):763-772
1. The biosynthesis of lipids and their distribution in several tissues were investigated by injection of 1-14C acetate in females and 5th instar nymphs of the hematophagous hemiptera T. infestans. 2. Biosynthesis of palmitic, palmitoleic, stearic, oleic and very long chain fatty acids up to 26 carbons and hydrocarbons, was shown. They were found in haemolymph, fat body, integument, epicuticle and oocytes with special distribution. 3. Epicuticular hydrocarbon labelling was shown to precede that of haemolymph hydrocarbons. 4. Radioactivity incorporation into each lipid class depends on the developmental stage and the time after injection. 5. "In vitro" incubation of integument tissue with 1-14C acetate demonstrated the biosynthesis of palmitic and stearic acids, a low desaturation to oleic and palmitoleic and an elongation to acids of up to 34 carbons. Hydrocarbons were also synthesized. 6. Haemolymph in the incubation medium has a positive effect on the release of newly-synthesized fatty acid and unsaponifiable material from the integument. 相似文献
999.
Effects of water-deficient stress and cotyledon excision on osmoregulation in hypocotyls of dark-grown mung bean seedlings were studied, and following results were obtained. Water-deficient stress inhibited hypocotyl elongation either in intact or decotylized seedlings. The inhibition was more conspicuous in decotylized seedlings than in intact ones. Water-deficient stress decreased osmotic potential in hypocotyls, while cotyledon excision increased it. The concentrations of soluble sugars, free amino acids and potassium ions in hypocotyls of intact or decotylized seedlings increased in response to water-deficient stress. Cotyledon excision reduced the concentration of soluble sugars and free amino acids, but it did not change the concentration of potassium ions, suggesting that a part of soluble sugars and free amino acids is transported from cotyledons. Unlike cotyledon excision, excision of the apex or roots had no influence on osmoregulation in response to water-deficient stress. Segments excised from hypocotyls had the ability to osmoregulate in response to water-deficient stress. Based on these results, the role of cotyledons in osmoregulation in response to water-deficient stress and quantitative relationships between osmotic potential and hypocotyl elongation in etiolated mung bean seedlings are discussed. 相似文献
1000.
Measuring oxygen diffusion coefficients with polarographic oxygen electrodes. II. Fermentation Media
Fermentation media consist of a large number of chemicals which composition undergoes alteration during the course of fermentations. In consequence, the conventional methods and correlations for gas diffusion coefficient measurement and prediction cannot be easily applied to such systems. Oxygen diffusion coefficients have been measured in simulated chemical systems as well as in complex solutions of nutrient broth, using the polarographic technique introduced in a previous article. It is identified that sugars and salts are the major factors influencing oxygen diffusion coefficients in these aqueous fermentation media. The effect of salts on oxygen diffusion coefficients in electrolyte solutions has been found to be well correlated with the square root of total ionic strength of electrolyte solutions. The individual effect of glucose and its combined effect with salts are explored in order to reach rational correlations capable of predicting oxygen diffusion coefficients in synthetic fermentation media. For aqueous solutions of glucose plus salts, it is observed that the log-additive relationship can be used to account for the combined effect. Finally, a linear correlation has been established in measuring oxygen diffusion coefficients in aqueous solutions having different concentrations of nutrient broth. 相似文献