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61.
62.
Lucidenic acid B induces apoptosis in human leukemia cells via a mitochondria-mediated pathway 总被引:2,自引:0,他引:2
Ganoderma lucidum is known as a medicinal mushroom used in traditional Chinese medicine. In the present study, the effect of lucidenic acids (A, B, C, and N) isolated from a new G. lucidum (YK-02) on induction of cell apoptosis and the apoptotic pathway in HL-60 cells were investigated. The results demonstrated that lucidenic acids decreased cell population growth of HL-60 cells, assessed with the MTT assay. The cell cycle assay indicated that treatment of HL-60 cells with lucidenic acid A, C, and N caused cell cycle arrest in the G 1 phase. Lucidenic acid B (LAB) did not affect the cell cycle profile; however, it increased the number of early and late apoptotic cells but not necrotic cells. Treatment of HL-60 cells with LAB caused loss of mitochondria membrane potential. Moreover, the ratio of expression levels of pro- and antiapoptotic Bcl-2 family members was changed by LAB treatment. LAB-induced apoptosis involved release of mitochondria cytochrome c and subsequently induced the activation of caspase-9 and caspase-3, which were followed by cleavage of poly(ADP-ribose) polymerase (PARP). Pretreatment with a general caspase-9 inhibitor (Z-LEHD-FMK) and caspase-3 inhibitor (Z-DEVD-FMK) prevented LAB from inhibiting cell viability in HL-60 cells. Our finding may be critical to the chemopreventive potential of lucidenic acid B. 相似文献
63.
Hsu TC Chiang SY Wu JH Tsai CC Huang CY Chen YC Tzang BS 《Journal of agricultural and food chemistry》2008,56(20):9685-9691
Cholesterol-rich diets are known to cause hepatic apoptosis, which has been associated with the pathogenesis of systemic lupus erythematosus (SLE). However, the mechanisms and treatments for hepatic apoptosis in SLE are poorly understood. To clarify the effects of taurine on hepatic apoptosis in SLE, NZB/W F1 mice received control, cholesterol, and cholesterol/taurine diets. Significant reductions of caspase-3 activity, TUNEL-positive cells, and Fas- and mitochondrial- dependent apoptosis were detected in liver from the cholesterol/taurine group as compared to the cholesterol group. Moreover, significant increases of phosphorylated AKT, NF-kappaB (p65), and ERK1/2 proteins were detected in liver from the cholesterol/taurine group as compared to the cholesterol group. In contrast, a significant reduction of phosphorylated p38 protein was observed in the cholesterol/taurine group. These experimental results demonstrated positive effects of taurine against hepatic apoptosis in NZB/W F1 mice fed a high-cholesterol diet and suggested the therapeutic potential of taurine in SLE. 相似文献
64.
Paddy and Water Environment - This study proposes a risk analysis model for quantifying the insufficient risk of rice production due to the climate change and variation in irrigation water and... 相似文献
65.
Alexander Burren Hannes Joerg Malena Erbe Arthur R. Gilmour Ulrich Witschi Fritz Schmitz‐Hsu 《Reproduction in domestic animals》2019,54(9):1177-1181
Variance components (VC) were estimated for the semen production trait ejaculate volume, sperm concentration and sperm motility in the Swiss cattle breeds Brown Swiss (BS), Original Braunvieh (OB), Holstein (HO), Red‐Factor‐Carrier (RF), Red Holstein (RH), Swiss Fleckvieh (SF) and Simmental (SI). For this purpose, semen production traits from 2,617 bulls with 124,492 records were used. The data were collected in the years 2000–2012. The model for genetic parameter estimation across all breeds included the fixed effects age of bull at collection, year of collection, month of collection, number of collection per bull and day, interval between consecutive collections, semen collector, bull breed as well as a random additive genetic component and a permanent environmental effect. The same model without a fixed breed effect was used to estimate VC and repeatabilities separately for each of the breeds BS, HO, RH, SF and SI. Estimated heritabilities across all breeds were 0.42, 0.25 and 0.09 for ejaculate volume, sperm concentration and sperm motility, respectively. Different heritabilities were estimated for ejaculate volume (0.42; 0.45; 0.49; 0.40; 0.10), sperm concentration (0.34; 0.30; 0.20; 0.07; 0.23) and number of semen portions (0.18; 0.30; 0.04; 0.14; 0.04) in BS, HO, RH, SF and SI breed, respectively. The phenotypic and genetic correlations across all breeds between ejaculate volume and sperm concentration were negative (?0.28; ?0.56). The other correlations across all breeds were positive. The phenotypic and genetic correlations were 0.01 and 0.19 between sperm motility and ejaculate volume, respectively. Between sperm motility and sperm concentration, the phenotypic and genetic correlations were 0.20 and 0.36, respectively. The results are consistent with other analyses and show that genetic improvement through selection is possible in bull semen production traits. 相似文献
66.
67.
Thuringiensin produced by Bacillus thuringiensis subsp. darmstadiensis was further subjected to a two-phase aqueous separation system. A modified HPLC method and a test for quantitative pathogenicity using the house fly Musca domestica were used for analysis of thuringiensin. Within a realistic range of dosages, more effect was observed in the pupal stage than in the larval stage. The percentage effective control rate (ECR) was calculated by (100-percentage emergence); malformed and non-reproductive adults were considered as emerged. Pupal mortality, pupal weight, and ECR after feeding the three-day-old larvae were the measured response criteria for bioassay. The EC50 of thuringiensin for pupae mortality was 1·64 μg ml-1 diet, and 0·83 μg ml-1 for mortality of adults. Insecticidal activity of the broth increased with fermentation time-course from 9th to 21st hour. The bioassay curve constructed with three-hour sampling interval during the fermentation course had good correlation to thuringiensin content as determined by the HPLC method. In the two-phase aqueous separation system, a maximum of 96·7% ECR was achieved with the bottom salt layer, compared to a value of 46·7% with the upper PEG layer. These results suggest that thuringiensin, prepared through a fermentation and recovery process, is suitable for pest control. © 1997 SCI. 相似文献
68.
Yi‐Jay Chang Kuo‐Wei Lan William A. Walsh Jhen Hsu Chih‐hao Hsieh 《Fisheries Oceanography》2019,28(3):291-304
We developed habitat suitability index (HSI) models for two size classes of Pacific saury Cololabis saira in the Northwestern Pacific Ocean. Environmental data, including sea surface temperature, sea surface height, salinity, and net primary production, and catch and effort data from Taiwanese distant‐water stick‐held dip net fisheries during the main fishing season (August–October) during 2002–2015 were used. Habitat preferences and suitable habitat area differed between size classes. The suitable habitat was located between 40–47.5°N and 145–165°E for large‐sized Pacific saury but encompassed a greater area (35–47°N and 140–165°E) for medium‐sized Pacific saury. Both size classes were affected by substantial interannual variation in the environmental variables, which in turn can be important in determining the potential fishing grounds. We found a significant negative relationship between the suitable habitat area and the Niño3.4 indices with a time‐lag of 6 months for the large‐sized (r = ?0.68) and medium‐sized (r = ?0.42) Pacific saury, respectively, as well as the total landings of Pacific saury by all fishing fleets (r = ?0.46). As remotely‐sensed environmental data become increasingly available, HSI models may prove useful for evaluation of possible changes in habitat suitability resulting from climate change or other environmental phenomena and in formulating scientific advice for management. 相似文献
69.
Travel and Activity Choices for Transit Travelers at Terminals with Dynamic Information Provision
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This study explores the impacts of providing dynamic information on travelers' behavior and the induced demand for terminal‐surrounding activities. A nested logit model was used to identify the important factors, and a questionnaire was designed to explore the preference of travelers regarding activities and travel choices. Adopting dynamic information was found to have a significant influence on travel decisions. The results show that an increased duration of activity participation may accompany an alteration of departure time or mode choice. The results also show that the use of dynamic information for travelers is related to induced activity participation and travelers' socioeconomic characteristics. The content of the dynamic information should be designed in accordance with the preference of travelers to encourage travelers participating in terminal‐surrounding activities. 相似文献
70.
Multiplex PCR genotyping for five bacterial blight resistance genes applied to marker‐assisted selection in rice (Oryza sativa)
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Bacterial blight (BB) is the most economically damaging disease of rice in Asia and other parts of the world. In this study, a multiplex PCR genotyping method was developed to simultaneously identify genotypes of five BB resistance genes, Xa4, xa5, Xa7, xa13 and Xa21. The resistance R alleles were amplified using five functional markers (FMs) to generate amplicons of 217, 103, 179, 381 and 595 bp in IRBB66. Amplicons of 198, 107, 87, 391 and 467 bp corresponded to susceptible alleles in Taiwanese japonica rice cultivars. In backcross breeding programmes, the multiplex PCR assay was integrated into selection from a population using BB resistance donor IRBB66 crossed to rice cultivar ‘Tainung82’. Two plants with homozygosity for Xa4, xa5, Xa7, xa13 and Xa21 were selected from 1100 BC2F2 plants. In addition, the five BB resistance genes were also accurately identified in F2 populations. This multiplex PCR method provides a rapid and efficient method for detecting various BB resistance genes, which will assist in pyramiding genes to improve durability of BB resistance in Taiwanese elite rice cultivars. 相似文献