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991.
A saponin fraction was isolated from Momordica charantia seeds by delipidation, saline extraction, ammonium sulfate precipitation, and extraction of the resulting supernatant with n-butanol. Thin-layer chromatography, in the upper phase of the n-butanol--ethyl acetate--water (4:1:5, by volume) system on plastic sheets coated with silica gel 60 F254, revealed the presence of a single spot after spraying with 10% sulfuric acid. The lack of contamination of the saponin preparation with proteins was judged by the absence of protein bands in sodium dodecyl sulfate--polyacrylamide gel electrophoresis, agarose electrophoresis and agarose diffusion, and by the absence of an absorption maximum around 278 nm. The saponin acted as a noncompetitive inhibitor of corticotropin, glucagon, and epinephrine in lipolysis in isolated rat adipocytes, and it also antagonized dibutyryl cAMP induced lipolysis. The antilipolytic activity was resistant to heat, trypsin, chymotrypsin, pronase, and glutathione, in keeping with the chemical nature of saponin. Incorporation of [3-3H]glucose into lipid was inhibited. Adipocyte viability and ATP content were not affected by the saponin, suggesting that its inhibitory effects on lipolysis and lipogenesis were not due to an adverse effect on cell viability. 相似文献
992.
Yan Zuo William S.B. Yeung Kai-Fai Lee 《Biochemical and biophysical research communications》2010,401(2):275-280
VAD1.3 (AEP1), a novel testis-specific gene, was first isolated from the testis of a retinol-treated vitamin-A-deficient (VAD) rat model. It is expressed at the acrosomal region of spermatids from postnatal day 25. VAD1.3 immunoreactivity is present in rat, human, monkey and porcine spermatids and spermatozoa, suggesting that VAD1.3 may play a role in acrosome formation. However, direct evidence on the detailed sub-cellular localization of the VAD1.3 protein in the acrosome and how VAD1.3 is involved in acrosome formation remains largely unknown. Here, we isolated and identified VAD1.3 interacting proteins by immunoprecipitation followed by mass spectrometry, and determined the functional motifs of VAD1.3 that were important for its specific sub-cellular location in vitro. We found that VAD1.3 bound to syntaxin 1 and β-actin proteins in vitro. Immunogold electron microscopic study localized VAD1.3 immunoreactivity to the acrosome membranes and matrix, and colocalized it with the β-actin protein. The full-length GFP-VAD (1-3601) and GFP-VAD (1-730) fusion proteins that contain the bipartite nucleus localization (BNL) signal were located in the peri-nucleus/Golgi of the transfected cells. In addition, the GFP signal colocalized with the endoplasmic reticulum marker and the syntaxin 1 protein in the transfected HeLa and GC-2spd cells. The C-terminal GFP-VAD (1770-3601) was expressed in the nucleus. Taken together, VAD1.3 interacts with β-actin and syntaxin 1 in vitro. The BNL signal may mediate the peri-nuclei localization of the protein that may interact with syntaxin 1 and β-actin for acrosome formation in spermatogenesis. 相似文献
993.
Jie Zhao Chaoqiang Jiang Tai Hing Lam Bin Liu Kar Keung Cheng Lin Xu Shiu Lun Au Yeung Weisen Zhang Gabriel M. Leung C. Mary Schooling 《PloS one》2015,10(5)
ObjectivesObservationally, testosterone is negatively associated with systemic inflammation, but this association is open to both residual confounding and reverse causality. Large-scale randomized controlled trials (RCTs), assessing exogenous effects, are presently unavailable. We examined the association of endogenous testosterone with well-established systemic inflammatory markers (white blood cell, granulocyte, lymphocyte and high-sensitivity C-reactive protein (hsCRP)) using a separate-sample Mendelian randomization analysis to minimize reverse causality.MethodsA genetic prediction rule for serum testosterone was developed in 289 young Chinese men with mean age of 21.0, using selected testosterone-related SNPs (rs10046, rs1008805 and rs1256031). Multivariable linear regression was used to examine the association of genetically predicted serum testosterone with inflammatory markers among 4,212 older Chinese men from the Guangzhou Biobank Cohort Study.ResultsGenetically predicted testosterone was unrelated to white blood cell count (-0.01 109/L per nmol/L testosterone, 95% confidence interval (CI) -0.05 to 0.04), granulocyte count (-0.02 109/L, 95% CI -0.06 to 0.02), lymphocyte count (0.005 109/L, 95% CI -0.01 to 0.02) and hsCRP (-0.05 mg/L, 95% CI -0.15 to 0.06).ConclusionOur findings did not corroborate any anti-inflammatory effects of testosterone or corresponding potentially protective effects of testosterone on chronic diseases resulting from reduced low-grade systemic inflammation. 相似文献
994.
Journal of Plant Research - Polyploidization has played an important role in the speciation and diversification of plant species. However, genetic analyses of polyploids are challenging because the... 相似文献
995.
996.
997.
Yu-Qiang Shi Yin-Chuan Li Xiao-Qian Hu Shang-Ying Liao Lin Huang Alan Y.B. Tang William S.B. Yeung Yi-Xun Liu 《Biochemical and biophysical research communications》2009,388(3):583-159
Temperature-related sequence 4 (Trs4) has been identified as a testis-specific gene with expression sensitive to the abdominal temperature changes induced by artificial cryptorchidism. In murine testes, Trs4 mRNA was detected in round spermatids and its protein was localized mainly in the elongating spermatids as well as in the acrosomes and tails of mature spermatozoa. Using a yeast two-hybrid screening system, we identified Rshl-2, Gstmu1, and Ddc8 as putative binding partners of the Trs4 protein in mouse testes. Their interactions were confirmed by in vivo and in vitro binding assays. Further studies demonstrated that Ddc8, a newly identified gene with unknown functions, displayed a similar expression pattern with Trs4 in mouse testes. In particular, Trs4, Ddc8, and Rshl-2 proteins were co-localized to the tails of mature spermatozoa. These results suggested that Trs4 might be involved in diverse processes of spermiogenesis and/or fertilization through interactions with its multiple binding partners. 相似文献
998.
Zhi Yang Aiham Qdaisat Zhihuang Hu Elizabeth A. Wagar Cielito Reyes-Gibby Qing H. Meng Sai-Ching J. Yeung 《PloS one》2016,11(4)
BackgroundSeptic shock may be associated with myocardial damage; however, the prognostic value of cardiac enzymes in cancer patients with septic shock is unknown. In this study, we evaluated the prognostic significance of cardiac enzymes in combination with established prognostic factors in predicting the 7-day mortality rate of patients with septic shock, and we constructed a new scoring system, Septic Oncologic Patients in Emergency Department (SOPED), which includes cardiac enzymes, to predict 7-day mortality rates.ConclusionsTroponin-I >0.05 ng/mL was an important predictor of short-term mortality (≤7 days). The SOPED scoring system, which incorporated troponin-I, was more prognostically accurate than were other scores for 7-day mortality. Large multicenter studies are needed to verify our results and prospectively validate the prognostic performance of the SOPED score. 相似文献
999.
Kara A. Michels Pauline Mendola Karen C. Schliep Edwina H. Yeung Aijun Ye Galit L. Dunietz 《Chronobiology international》2020,37(2):260-271
ABSTRACTDespite research indicating that sleep disorders influence reproductive health, the effects of sleep on reproductive hormone concentrations are poorly characterized. We prospectively followed 259 regularly menstruating women across one to two menstrual cycles (the BioCycle Study, 2005–2007), measuring fasting serum hormone concentrations up to eight times per cycle. Women provided information about daily sleep in diaries and chronotype and night/shift work on a baseline questionnaire. We evaluated percent differences in mean hormone concentrations, the magnitude of shifts in the timing and amplitude of hormone peaks, and the risk for sporadic anovulation associated with self-reported sleep patterns and night/shift work. We estimated chronotype scores – categorizing women below and above the interquartile range (IQR) as “morning” and “evening” chronotypes, respectively. For every hour increase in daily sleep duration, mean estradiol concentrations increased by 3.9% (95% confidence interval [CI] 2.0, 5.9%) and luteal phase progesterone by 9.4% (CI 4.0, 15.2%). Receiving less than 7 hours of sleep per day was associated with slightly earlier rises in peak levels for several hormones. Women reporting night/shift work (n = 77) had lower testosterone relative to women employed without night/shift work (percent difference: ?9.9%, CI ?18.4, ?0.4%). Women with morning chronotypes (n = 47) had earlier rises in estradiol during their cycles and potentially an earlier rise in luteinizing hormone. Compared to those who had intermediate chronotypes, women with evening chronotypes (n = 42) had a later luteinizing hormone peak of borderline statistical significance. A reduced risk for sporadic anovulation was suggested, but imprecise, for increasing hours of daily sleep leading up to ovulation (risk ratio 0.79, CI 0.59, 1.06), while an imprecise increased risk was observed for women with morning chronotypes (risk ratio 2.50, CI 0.93, 6.77). Sleep-related hormonal changes may not greatly alter ovarian function in healthy women, but have the potential to influence gynecologic health. 相似文献
1000.
Book reviewed in this article:
Crafting Exhibitions: Contemporary Navajo Weaving: The Gloria F. Ross Collection of the Denver Art Museum .
Crafting Exhibitions: Reflections of the Weavers' World: The Gloria F. Ross Collection of the Denver Art Museum . 相似文献
Crafting Exhibitions: Contemporary Navajo Weaving: The Gloria F. Ross Collection of the Denver Art Museum .
Crafting Exhibitions: Reflections of the Weavers' World: The Gloria F. Ross Collection of the Denver Art Museum . 相似文献