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981.
Although biochemists and geneticists have studied the cotton flower for more than one century, little is known about the molecular mechanisms underlying the dramatic color change that occurs during its short developmental life following blooming. Through the analysis of world cotton germplasms, we found that all of the flowers underwent color changes post-anthesis, but there is a diverse array of petal colors among cotton species, with cream, yellow and red colors dominating the color scheme. Genetic and biochemical analyses indicated that both the original cream and red colors and the color changes post-anthesis were related to flavonoid content. The anthocyanin content and the expression of biosynthesis genes were both increased from blooming to one day post-anthesis (DPA) when the flower was withering and undergoing abscission. Our results indicated that the color changes and flavonoid biosynthesis of cotton flowers were precisely controlled and genetically regulated. In addition, flavonol synthase (FLS) genes involved in flavonol biosynthesis showed specific expression at 11 am when the flowers were fully opened. The anthocyanidin reductase (ANR) genes, which are responsible for proanthocyanidins biosynthesis, showed the highest expression at 6 pm on 0 DPA, when the flowers were withered. Light showed primary, moderate and little effects on flavonol, anthocyanin and proanthocyanidin biosynthesis, respectively. Flavonol biosynthesis was in response to light exposure, while anthocyanin biosynthesis was involved in flower color changes. Further expression analysis of flavonoid genes in flowers of wild type and a flavanone 3-hydroxylase (F3H) silenced line showed that the development of cotton flower color was controlled by a complex interaction between genes and light. These results present novel information regarding flavonoids metabolism and flower development. 相似文献
982.
Yingfeng Tu Lin Wan Yuhua Fan Kezheng Wang Lihong Bu Tao Huang Zhen Cheng Baozhong Shen 《PloS one》2013,8(10)
Background
Ischemic postconditioning (IPost) protects the reperfused heart from infarction which has drawn much attention recently. However, studies to date have rarely investigated the role of microRNAs (miRNAs) in IPost. The aims of this study were to investigate whether miR-21 is involved in the protective effect of IPost against myocardial ischemia-reperfusion (I/R) injury and disclose the potential molecular mechanisms involved.Methods and Results
We found that miR-21 was remarkably up-regulated in mouse hearts after IPost. To determine the protective role of IPost-induced miR-21 up-regulation, the mice were divided into the following four groups: I/R group; I/R+IPost group (I/R mice treated with IPost); Antagomir-21+IPost+I/R group (I/R mice treated with anagomir-21 and IPost); Scramble+IPost+I/R group (I/R mice treated with scramble and IPost). The results showed IPost could reduce I/R injury-induced infarct size of the left ventricle, improve cardiac function, and prevent myocardial apoptosis, while knockdown of miR-21 with antagomir-21 could reverse these protective effects of IPost against mouse I/R injury. Furthermore, we confirmed that miR-21 plays a protective role in myocardial apoptosis through PTEN/Akt signaling pathway, which was abrogated by the PI3K inhibitor LY294002. The protective effect of miR-21 on myocardial apoptosis was further revealed in mouse hearts after IPost treatment in vivo.Conclusions
Our data clearly demonstrate that miR-21 is involved in IPost-mediated cardiac protection against I/R injury and dysfunction through the PTEN/Akt signaling pathway in vivo. Identifying the beneficial roles of IPost-regulated miRNAs in cardiac protection, which may be a rational target selection for ischemic cardioprotection. 相似文献983.
Background
Mounting evidence supports the use of laparoscopic techniques for the treatment of simple appendicitis. However, most of the advantages of these techniques are of limited clinical relevance. This study compares the treatment outcomes of laparoscopic appendectomies and open appendectomies performed in Taiwan.Methods
This study uses data from the 2007 to 2009 Taiwan National Health Insurance Research Database. The study sample included 65,339 patients, hospitalized with a discharge diagnosis of acute appendicitis (33.8% underwent laparoscopic appendectomy). A generalized estimated equation (GEE) was performed to explore the relationship between the use of laparoscopy and 30-day re-admission. Hierarchical linear regressions were performed to examine the relationship between the use of laparoscopy, the length of stay (LOS), and the cost per discharge.Results
A significantly lower proportion of patients undergoing laparoscopic appendectomies were re-admitted within 30 days of their index appendectomy, in comparison to patients undergoing open appendectomies (0.66% versus 1.925, p<0.001). Compared with patients undergoing open appendectomies, patients undergoing laparoscopic appendectomies had a shorter LOS (4.01 versus 5.33 days, p<0.001) and a higher cost per discharge (NT$40,554 versus NT$38,509, p<0.001. In 2007, the average exchange rate was US$1 = NT$31.0). GEE revealed that the odds ratio of 30-day readmission for patients undergoing laparoscopic appendectomy was 0.38 (95% CI = 0.33–0.46) that of patients undergoing open appendectomies, after adjusting for surgeon, hospital, and patient characteristics, as well as for the clustering effect of particular surgeons and the propensity score.Conclusion
This study found that laparoscopic appendectomies had a lower 30-day re-admission rate, and a shorter LOS, but a slightly higher cost per discharge than open appendectomies. 相似文献984.
985.
R.A. Gibson M.A. Neumann E.L. Lien K.A. Boyd W.C. Tu 《Prostaglandins, leukotrienes, and essential fatty acids》2013,88(1):139-146
The conversion of the plant-derived omega-3 (n-3) α-linolenic acid (ALA, 18:3n-3) to the long-chain eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) can be increased by ALA sufficient diets compared to ALA deficient diets. Diets containing ALA above an optimal level result in no further increase in DHA levels in animals and humans. The present study evaluates means of maximizing plasma DHA accumulation by systematically varying both linoleic acid (LA, 18:2n-6) and ALA dietary level. Weanling rats were fed one of 54 diets for three weeks. The diets varied in the percentage of energy (en%) of LA (0.07–17.1 en%) and ALA (0.02–12.1 en%) by manipulating both the fat content and the balance of vegetable oils. The peak of plasma phospholipid DHA (>8% total fatty acids) was attained as a result of feeding a narrow dietary range of 1–3 en% ALA and 1–2 en% LA but was suppressed to basal levels (~2% total fatty acids) at dietary intakes of total polyunsaturated fatty acids (PUFA) above 3 en%. We conclude it is possible to enhance the DHA status of rats fed diets containing ALA as the only source of n-3 fatty acids but only when the level of dietary PUFA is low (<3 en%). 相似文献
986.
Kevin J. Filipski Angel Guzman-Perez Jianwei Bian Christian Perreault Gary E. Aspnes Mary T. Didiuk Robert L. Dow Richard F. Hank Christopher S. Jones Robert J. Maguire Meihua Tu Dongxiang Zeng Shenping Liu John D. Knafels John Litchfield Karen Atkinson David R. Derksen Francis Bourbonais Jeffrey A. Pfefferkorn 《Bioorganic & medicinal chemistry letters》2013,23(16):4571-4578
Glucokinase activators are a class of experimental agents under investigation as a therapy for Type 2 diabetes mellitus. An X-ray crystal structure of a modestly potent agent revealed the potential to substitute the common heterocyclic amide donor–acceptor motif for a pyridone moiety. We have successfully demonstrated that both pyridone and pyrimidone heterocycles can be used as a potent donor–acceptor substituent. Several sub-micromolar analogs that possess the desired partial activator profile were synthesized and characterized. Unfortunately, the most potent activators suffered from sub-optimal pharmacokinetic properties. Nonetheless, these donor–acceptor motifs may find utility in other glucokinase activator series or beyond. 相似文献
987.
Minhang Xin Jun Wen Feng Tang Chongxing Tu Han Shen Xinge Zhao 《Bioorganic & medicinal chemistry letters》2013,23(24):6777-6783
Hedgehog signaling pathway inhibitors are emerging as new therapeutic intervention against cancer. A novel series of N-(2-pyrimidinylamino) benzamide derivatives as hedgehog signaling pathway inhibitors were designed and synthesized. Most compounds presented significant inhibitory effect on hedgehog signaling pathway, among which 21 compounds exhibited more potent than vismodegib. Furthermore, compound 6a showed moderate pharmacokinetic properties in vivo, representing a promising lead compound for further exploration. 相似文献
988.
A novel,major, and validated QTL for the effective tiller number located on chromosome arm 1BL in bread wheat 总被引:2,自引:0,他引:2
Liu Jiajun Tang Huaping Qu Xiangru Liu Hang Li Cong Tu Yang Li Shuiqing Habib Ahsan Mu Yang Dai Shoufeng Deng Mei Jiang Qiantao Liu Yaxi Chen Guoyue Wang Jirui Chen Guangdeng Li Wei Jiang Yunfeng Wei Yuming Lan Xiujin Zheng Youliang Ma Jian 《Plant molecular biology》2020,104(1-2):173-185
Plant Molecular Biology - A novel and major QTL for the effective tiller number was identified on chromosomal arm 1BL and validated in two genetic backgrounds The effective tiller number (ETN)... 相似文献
989.
Gardiner Alastair T. Nguyen-Phan Tu C. Cogdell Richard J. 《Photosynthesis research》2020,145(2):83-96
Photosynthesis Research - All purple photosynthetic bacteria contain RC–LH1 ‘Core’ complexes. The structure of this complex from Rhodobacter sphaeroides, Rhodopseudomonas... 相似文献
990.
Ying-ping Huang Ali Haris Malik Zhi-ying Tu David Johnson Wei-Ming Li Xi Yuan 《Zeitschrift fur angewandte Ichthyologie》2020,36(6):811-816
The swimming performance of juvenile rock carp (Procypris rabaudi, Tchang) subjected to repeated fatigue exercise was studied using a flume-type respirometer at 20°C. The critical swimming speed (Ucrit) and oxygen consumption rate (MO2) of juvenile rock carp were measured during two successive stepped velocity tests, following a 60 min rest interval. Ucrit of rock carp was giving a recovery ratio (Rr) of 92.64%, and exertion exercise decreases Ucrit. When MO2 was plotted as a linear function of U, the slope for trial 1 was 1.06 and 1.50 for trial 2, indicating a decreasing in swimming efficiency. The maximum metabolic rate (MMR) increased from 17.06 ± 1.14 mmol O2/(kg·hr) to 19.14 ± 1.23 mmol O2/(kg·hr), and the exercise post oxygen consumption rate (EPOC) increased from 9.00 to 9.65 mmol O2/kg. Repeated fatiguing exercise increased both the aerobic and anaerobic cost of reaching Ucrit, but anaerobic metabolism accounted for a larger proportion in the trial 2. The data investigation on the swimming performance and the physiological response to fatigue provide important design criteria for fishways. 相似文献