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Lung adenocarcinoma is a major form of non–small-cell lung cancer that frequently strikes nonsmokers. The disease is often diagnosed at a late stage and the 5-year survival rate is very low. Although previous studies found many somatic alterations associated with lung adenocarcinoma, the molecular basis of the development and progression of the disease is not well understood. We found that long noncoding RNA (lncRNA) cancer susceptibility candidate 2 (CASC2), a putative tumor suppressor, was downregulated in both patient adenocarcinoma tissues and cultured lung cancer cells. Its tumor suppression function seemed to be dependent on its binding to miR-4735-5p. Changing the levels of CASC2 and miR-4735-3p in the cultured adenocarcinoma cells could affect the malignant phenotypes as well as growth of tumors derived from the cells injected into nude mice. Furthermore, the lncRNA and miR-4735-3p interplay likely the suppressed tumor growth through the downstream mammalian target of rapamycin signaling pathway. The results have revealed molecular details that may be critical for the development of lung adenocarcinoma, opening opportunities for the development of novel, and therapeutic tools.  相似文献   
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UDP‐glucuronosyltransferases (UGTs)‐catalyzed glucuronidation conjugation reaction plays an important role in the elimination of many important clinical drugs and endogenous substances. The present study aims to investigate the enantioselective inhibition of carprofen towards UGT isoforms. In vitro a recombinant UGT isoforms‐catalyzed 4‐methylumbelliferone (4‐MU) glucuronidation incubation mixture was used to screen the inhibition potential of (R)‐carprofen and (S)‐carprofen towards multiple UGT isoforms. The results showed that (S)‐carprofen exhibited stronger inhibition potential than (R)‐carprofen towards UGT2B7. However, no significant difference was observed for the inhibition of (R)‐carprofen and (S)‐carprofen towards other UGT isoforms. Furthermore, the inhibition kinetic behavior was compared for the inhibition of (S)‐carprofen and (R)‐carprofen towards UGT2B7. A Lineweaver–Burk plot showed that both (S)‐carprofen and (R)‐carprofen exhibited competitive inhibition towards UGT2B7‐catalyzed 4‐MU glucuronidation. The inhibition kinetic parameter (Ki) was calculated to be 7.0 μM and 31.1 μM for (S)‐carprofen and (R)‐carprofen, respectively. Based on the standard for drug–drug interaction, the threshold for (S)‐carprofen and (R)‐carprofen to induce a drug–drug interaction is 0.7 μM and 3.1 μM, respectively. In conclusion, enantioselective inhibition of carprofen towards UDP‐glucuronosyltransferase (UGT) 2B7 was demonstrated in the present study. Using the in vitro inhibition kinetic parameter, the concentration threshold of (S)‐carprofen and (R)‐carprofen to possibly induce the drug–drug interaction was obtained. Therefore, clinical monitoring of the plasma concentration of (S)‐carprofen is more important than (R)‐carprofen to avoid a possible drug–drug interaction between carprofen and the drugs mainly undergoing UGT2B7‐catalyzed metabolism. Chirality 27:189–193, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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A dinosaur tracksite in the Lower Jurassic Ziliujing Formation of Sichuan Province, China consists of a spectacular sub-vertical exposure, with multiple track-bearing levels and trackways showing parallel and bimodal orientations. Based on well-preserved material, the new ichnogenus and ichnospecies, Liujianpus shunan ichnogen. nov. ichnosp. nov. is erected to accommodate distinctive sauropodomorph trackways occurring in this assemblage. Liujianpus has a unique combination of features, some relating to the early Jurassic basal sauropodomorph (prosauropod in traditional usage) ichnogenus Otozoum, others to the sauropod ichnogenus Brontopodus. Despite such a mix of basal sauropodomorph- and sauropod-like features, the trackmaker of Liujianpus is likely a basal sauropodomorph. This identification is consistent with the occurrence of basal sauropodomorph skeletons from geographically and chronologically close localities. The other distinct morphotype from the tracksite is linked to a sauropod trackmaker. As such, the ichnofauna consisting of two distinct foot morphotypes reflects the diversity of sauropodomorph dinosaurs in the Early Jurassic of Asia.  相似文献   
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中国大鲵视网膜的光镜和扫描电镜研究   总被引:6,自引:0,他引:6  
用光镜和扫描电镜观察了大鲵视网膜各类细胞的形态及分布, 对视细胞和节细胞进行计数。视网腊中三个核层及两个网状层分布均匀,无中央凹。每张视网膜的视细胞总数约130000,节细胞约8000,视杆与视锥之比为8.5:1。扫描电镜下,视杆外节表面的小叶间沟清晰;视杆视锥外节均有从内节伸出的20-30条萼状突起;核周体表面亦有20-30条细胞质突起。文中还报道了幼体视细胞的形态及密度。讨论了上述结构的机能。  相似文献   
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郭鹤宝  何山文  王星  章俊  张晓霞 《微生物学报》2019,59(12):2285-2295
【目的】Pantoea菌株是广泛分布在自然界中的一类功能多样的细菌。本研究对分离自水稻种子内生的Pantoea菌株进行系统发育分析及功能评价,从而确定分类地位、种类多样性、分布特征及功能特性。【方法】采用乙醇-次氯酸钠联合灭菌方法进行水稻种子的表面灭菌,进行内生细菌的分离与纯化;其次将纯化后的菌株进行16Sr RNA基因PCR扩增及序列分析,通过MEGA7软件构建系统发育树;将分离得到的菌株进行功能实验检测,如溶磷、产IAA、产铁载体、拮抗病原真菌等特性,最后检测菌株的溶血性;水稻分型采用SSR方法,并对水稻农学性状如分蘖数、株高、植株重及产量进行调查。【结果】本研究对分离自8个不同基因型水稻种子中的146株内生Pantoea菌株进行系统发育分析及功能评价,结果发现所分离到的泛菌菌株主要属于Pantoea dispersa、Pantoea agglomerans、Pantoea cypripedii以及Pantoea brenneri四个种,其中P. dispersa的菌株数量最多,分布最广,并且存在于所有的8个水稻种子样品中。对其中66株菌进行功能检测,发现86.3%和69.7%的菌株具有溶磷和产IAA能力,有7株菌具有产铁载体能力,未发现对真菌病害Fusarium moniliforme有拮抗作用的菌株,并发现3株菌具有溶血性;本实验未发现泛菌组成与水稻系统发育及农学性状存在明显的相关性。【结论】本研究首次对水稻种子中泛菌的多样性及其功能进行报道,发现不同基因型的水稻种子所含Pantoea种类及组成存在差异,种子选择性地积累了Pantoea类群,大部分菌株具有一定的促生特性。该研究结果有助于进一步探究微生物与植物的共进化、种子微生物的传播途径及作用方式。  相似文献   
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在中国农业微生物菌种中心(ACCC)菌株的定期转接保藏过程中,发现解淀粉芽孢杆菌ACCC 19742在同一培养基上出现两种不同的菌落形态,将这两个不同形态的菌株编号为19742-1和19742-2。通过形态学、生理生化及基因组分析相结合鉴定不同菌落形态ACCC 19742,并进一步确定该菌株的分类地位。首先将菌株进行分离与纯化,其次将纯化后的菌株进行16S rRNA及gyrB基因扩增及序列分析,通过MEGA 7.0软件构建系统发育树;API 20NE、BIOLOG及脂肪酸等分析菌株的生理生化特性;全基因组分析菌株的ANI和DDH值。两株菌在API 20NE中,仅葡萄糖酸盐同化反应存在差异;脂肪酸检测中主要组成相同,仅是百分含量方面略有差别;两株菌的16S rRNA基因相似性为100%,gyrB基因的相似性为99.4%;全基因组测序表明,两株菌的ANI值为99.95%,DDH值为99.62%。综合遗传学特征和表型特征,证实两者为来源于同一菌株不同的形态变异型,而并非污染所致。同时,19742-1和19742-2与Bacillus velezensis NRRL_B 41580~T的ANI及DDH值最高,分别为97%和77%,且16S rRNA和gyrB系统进化分析也表明,该菌株在分类地位上属于贝莱斯芽孢杆菌(Bacillus velezensis),而非解淀粉芽孢杆菌。这为菌株的保藏提供了一定的参考价值。  相似文献   
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We compared the current prevalence of increased BMI and type 2 diabetes in a representative group of Tongan subjects with measurements made in 1973, and we determined the distribution and possible interrelations with the UCP2 insertion/deletion (ins/del) polymorphism of these variables. We documented the BMI, glucose tolerance, and standard lipid variables in 1012 Tongan subjects (429 men and 583 women, ages 15 to 85 years) during 1998 and 2000 and compared the BMI findings with those of the 1973 survey. We also genotyped for the UCP2 ins/del polymorphism, assessed its association with obesity and type 2 diabetes, and compared its prevalence with those reported for other ethnic populations. The mean BMI ± SD was greatly increased in both men (30.2 ± 5.4 kg/m2) and women (33.8 ± 6.2 kg/m2), representing increases since 1973 of 11.9% and 19.4%, respectively. The genotype frequencies were 97% for the del/del genotype and 3% for the ins/del genotype; we found no ins/ins homozygotes. This distribution is strikingly different from those reported for white, South Indian, Pima Native‐American, and Asian populations (49 to 77% for del/del genotype). We conclude that there is a marked prevalence of obesity in Tonga, a prevalence that has increased since 1973. We also conclude that there is a unique, near‐uniform distribution of the UCP2 45‐bp ins/del polymorphism in Tongans. This may be the result of a founder effect and may be relevant to the prevalence of obesity and type 2 diabetes in Tonga.  相似文献   
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