Tauroursodeoxycholate (TUDCA), chemical chaperone, enhances function of islets by reducing ER stress

The exposure to acute or chronic endoplasmic reticulum (ER) stress has been known to induce dysfunction of islets, leading to apoptosis. The reduction of ER stress in islet isolation for transplantation is critical for islet protection. In this study, we investigated whether tauroursodeoxycholate (TUDCA) could inhibit ER stress induced by thapsigargin, and restore the decreased glucose stimulation index of islets. In pig islets, thapsigargin decreased the insulin secretion by high glucose stimulation in a time-dependent manner (1 h, 1.35 ± 0.16; 2 h, 1.21 ± 0.13; 4 h, 1.17 ± 0.16 vs. 0 h, 1.81 ± 0.15, n = 4, p < 0.05, respectively). However, the treatment of TUDCA restored the decreased insulin secretion index induced by thapsigargin (thapsigargin, 1.25 ± 0.12 vs. thapsigargin + TUDCA, 2.13 ± 0.19, n = 5, p < 0.05). Furthermore, the culture of isolated islets for 24 h with TUDCA significantly reduced the rate of islet regression (37.4 ± 5.8% vs. 14.5 ± 6.4%, n = 12, p < 0.05). The treatment of TUDCA enhanced ATP contents in islets (27.2 ± 3.2 pmol/20IEQs vs. 21.7 ± 2.8 pmol/20IEQs, n = 9, p < 0.05). The insulin secretion index by high glucose stimulation is also increased by treatment of TUDCA (2.42 ± 0.15 vs. 1.92 ± 0.12, n = 12, p < 0.05). Taken together, we suggest that TUDCA could be a useful agent for islet protection in islet isolation for transplantation.     

骆驼瘤胃耐受/降解去氢骆驼蓬碱细菌的筛选

【目的】中药骆驼蓬含多种生物碱,对动物有毒性。生活于荒漠半荒漠的骆驼可采食部分有毒植物而不中毒。为了解骆驼瘤胃微生物对骆驼蓬植物毒素的耐受与降解能力进行本研究。【方法】以含100mg/L纯品去氢骆驼蓬碱的M98-5培养基接种骆驼瘤胃内容物,经五代胁迫培养后分离可耐受/降解去氢骆驼蓬碱的细菌,以薄层析法检验其降解活力,以16SrRNA序列分析其进化地位。【结果】29个分离株中15株具有降解去氢骆驼蓬碱活性;16SrRNA序列分析显示,属于乳杆菌属(Lactobacillus)16株,占55%;志贺氏菌属(Shigella)7株,占24%;芽孢杆菌属(Bacillus)4株,占13.8%;肠球菌属(Enterococcus)和巨型肠球菌属(Megasphaera)各1株。【结论】可耐受/降解去氢骆驼蓬碱的骆驼瘤胃细菌仅限于少数几类,且检测到的具有降解活力的只有乳杆菌类。     

Development and characterization of microsatellite loci in Taihangia rupestris (Rosaceae), a rare cliff herb

? Premise of the study: Microsatellite primers were developed for the rare Taihangia rupestris (Rosaceae) to evaluate genetic diversity, population genetic structure, mating system, and demographic events of this species. ? Methods and Results: Ten primer sets were developed using an enriched genomic library and were successfully amplified in T. rupestris var. ciliata and T. rupestris var. rupestris. The number of alleles per locus ranged from 2 to 21; the observed and expected heterozygosities ranged from 0.300 to 0.950 and from 0.328 to 0.956, respectively, in the two varieties. ? Conclusions: The markers described here will be useful for studies of genetic variation, genetic structure, and mating systems of T. rupestris, which are important for the future conservation of this rare species.     

成釉质细胞分化机制的研究进展

牙齿的发育是由牙上皮和神经脊来源的间充质之间的连续的相互诱导产生的.上皮和间充质之间连续的相互诱导,使得上皮细胞分化为具有分泌牙釉质功能的成釉质细胞,而间充质细胞分化为具有分泌牙本质功能的成牙本质细胞.成釉质细胞的正常分化对于形成正常的牙釉质是至关重要的,本文主要对细胞信号分子、细胞黏附分子、釉质特异性基因和转录因子等在成釉质细胞分化过程中的作用做一概述.     

Characterization and mapping of a novel mutant sms1 （senescence and male sterility 1） in rice

Plant senescence plays diverse important roles in development and environmental responses.However,the molecular basis of plant senescence is remained largely unknown.A rice spontaneous mutant with the character of early senescence and male sterility (sms) was found in the breeding line NT10-748.In order to identify the gene SMS1 and the underlying mechanism,we preliminarily analyzed physiological and biochemical phenotypes of the mutant.The mutant contained lower chlorophyll content compared with the wild type control and was severe male sterile with lower pollen viability.Genetic analysis showed that the mutant was controlled by a single recessive gene.By the map-based cloning approach,we fine-mapped SMS1 to a 67 kb region between the markers Z3-4 and Z1-1 on chromosome 8 using 1,074 F2 recessive plants derived from the cross between the mutant sms1 (japonica) × Zhenshan 97 (indica),where no known gene involved in senescence or male sterility has been identified.Therefore the SMS1 gene will be a novel gene that regulates the two developmental processes.The further cloning and functional analysis of the SMS1 gene is under way.     

The phylogeny of Orthoptera inferred from mtDNA and description of Elimaea cheni （Tettigoniidae： Phaneropterinae） mitogenome

The complete 15,831 bp nucleotide sequence of the mitochondrial genome from Elimaea cheni(Phaneropterinae)was determined.The putative initiation codon for cox1 was TTA.The phylogeny of Orthoptera based on different mtDNA datasets were analyzed with maximum likelihood(ML)and Bayesian inference(BI).When all 37 genes(mtDNA)were analyzed simultaneously,the monophyly of Caelifera and Ensifera were recovered in the context of our taxon sampling.The phylogeny of Orthoptera was largely consistent with previous phylogenetie hypotheses.Rhaphidophoridae to be a sister group of Tettigoniidae,and the relationships among four subfamilies of Tettigoniidae were(Phaneropterinae+(Conocephalinae+(Bradyporinae+Tettigoniinae))).Pyrgomorphidae was the most basal group of Caelifera.The relationships among six acridid subfamilies were(Oedipodinae+(Acridinae+(Gomphocerinae+(Oxyinae+(Calliptaminae +Cyrtacanthaeridinae))))).However,we did not recover a monophyletic Grylloidea.Myrmecophilidae clustered into one clade with Gryllotalpidae instead of with Gryllidae.ML and BI analyses of all protein coding genes(using all nucleotide sequence data or excluding the third codon position,and amino acid sequences)revealed a topology identical to that of the entire mtDNA genome dataset.However,22 tRNAs genes excluding the DHU loop and T()C loop(TRNA),and two rRNA genes(RRNA)perform poorly when analyzed as single dataset.Our results suggest that the best phylogenetie inferences were ML and BI methods based on total mtDNA.Excluding tRNA genes,rRNA genes and the third codon position of protein coding genes from dataset and converting nucleotide sequences to amino acid sequences do not positively affect phylogenetic reconstruction.     

DNA barcoding provides distinction between Radix Astragali and its adulterants

Based on variable nuclear and/or organellar DNA sequences among vastly divergent species as well as morphologically indistinguishable species, DNA barcoding is widely applicable in species identification, biodiversity studies, forensic analyses, and authentication of medicinal plants. The roots of Astragalus membranaceus and A. membranaceus var. mongholica are commonly used as Radix Astragali in several Asian countries, including China, Japan, and Korea. However, in addition to the two species recorded in the Chinese Pharmacopoeia, there are twenty-three species from different genera including Astragalus, Oxytropis, Hedysarum, and Glycyrrhiza, which have been used as adulterants not only in trading markets but also by the herbal medicine industry. Therefore, a simple, reliable, and accurate classification method is important for distinguishing authentic Radix Astragali from its adulterants. In this study, we acquired data for 37 samples from four related genera within the family Fabaceae. Then we compared four candidate DNA barcoding markers using ITS, matK, rbcL, and coxI sequences from nuclear, chloroplast, and mitochondrial genomes, all commonly used for plants to identify genetic variations among genera, intraspecies, and interspecies. We observed higher divergences among genera and interspecies for ITS, which have the average Kimura 2-parameter distances of 4.5% and 14.1%, respectively, whereas matK was found to have sufficient divergence at the intraspecific level. Moreover, two indels detected in the matK sequence are useful for PCR studies in distinguishing Radix Astragali from its adulterants. This study suggests that the combined barcoding regions of ITS and matK are superior barcodes for Radix Astragali and further studies should focus on evaluating the applicability and accuracy of such combined markers for a wide range of traditional Chinese herbs.     

Parents' Knowledge about Enterobiasis Might Be One of the Most Important Risk Factors for Enterobiasis in Children

To know the prevalence of Enterobius vermicularis infection and what are the most important risk factors, we evaluated the incidence and risk factors of enterobiasis among children attended in kindergartens in Busan metropolitan city, Republic of Korea. A total of 1,674 children from 21 kindergartens in 11 of 16 autonomous districts of Busan were evaluated for E. vermicularis infection by the cellotape anal swab technique. The overall egg-positive rate for E. vermicularis was 10.7% (179/1,674), and the prevalence of enterobiasis in each kindergarten ranged between 0% and 32.4%. There was an increasing tendency of the egg positive rate according to the population density; the higher the population density communities had, the higher egg-positive rate for E. vermicularis was detected (P = 0.001). Among personal hygiene factors involving children, thumb-sucking (P = 0.036) and fingernail-trimming (P = 0.024) were highly associated with enterobiasis. In addition, taking anthelmintic medications against E. vermicularis infection was strongly associated with enterobiasis (P = 0.014). Moreover, parents'' knowledge of enterobiasis was correlated significantly with the incidence of enterobiasis of their children (P = 0.006). In conclusion, we need to consider not only personal hygiene but also parents'' knowledge about enterobiasis as a factor in order to develop new strategies for elimination or to complete reduction of enterobiasis in Korea.