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1.
Previous data on association between CYP2E1 Rsa I/Pst I polymorphism and oral cancer risk were controversial. To investigate the association between CYP2E1 Rsa I/Pst I polymorphism and oral cancer risk. We performed a meta-analysis to assess the relationship between oral cancer and genotype with English language until June 2010. Twelve published case–control studies of 1259 patients with oral cancer and 2262 controls were acquired. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the association in codominant and dominant models. Overall, the pooled ORs indicated a significant association between CYP2E1 Rsa I/Pst I polymorphism and oral cancer risk (for c1/c2 vs. c1/c1: OR = 1.30, 95% CI = 1.04–1.62, Pheterogeneity = 0.57; for (c1/c2 + c2/c2) vs. c1/c1: OR = 1.32, 95% CI = 1.07–1.64, Pheterogeneity = 0.57, respectively). In subgroup analysis by race, the same significant risks were found among Asian (for c1/c2 vs. c1/c1: OR = 1.41, 95% CI = 1.05–1.91, Pheterogeneity = 0.92; for (c1/c2 + c2/c2) vs. c1/c1: OR = 1.43, 95% CI = 1.08–1.88, Pheterogeneity = 0.97, respectively). In conclusion, this meta-analysis demonstrates that CYP2E1 Rsa I/Pst I c2 allele may be a biomarker for oral cancer, especially among Asian populations.  相似文献   

2.
The gene polymorphism of Cytochrome P450 2E1 (CYP2E1) is supposed to be associated with cancer susceptibility. Many studies focusing on the Pst I/Rsa I polymorphism of CYP2E1 gene and hepatocellular carcinoma (HCC) risk have been conducted and the results are conflicting. In the current study, a meta-analysis of published studies was performed to assess the association between CYP2E1 Pst I/Rsa I polymorphism and risk to HCC. 11 studies containing 1,178 cases and 1,623 controls were selected to determine whether c2 allele of CYP2E1 gene can increase HCC susceptibility, especially through interacting with alcohol drinking. Using the random effects model, the result indicated that there was no association between CYP2E1 Pst I/Rsa I genotype and HCC risk [odds ratio (OR) 1.03 (95 % confidence interval (CI): 0.76–1.40) for c2 variant allele and OR 0.82 (95 % CI: 0.51–1.31) for c2 homozygotes compared with wild-type homozygotes]. The association between CYP2E1 (c2) variant allele and HCC susceptibility were found when interacting with alcohol [OR 2.88 (95 % CI: 1.25–6.60)]. In conclusion, this meta-analysis results showed that Pst I/Rsa I polymorphism of CYP2E1may slightly increase the risk of HCC and alcohol consumption increases the probability of developing HCC, especially for the carriers of some CYP2E1 alleles. CYP2E1 Pst I/Rsa I polymorphism may contribute to the proportion cases of HCC, which needs further investigations.  相似文献   

3.
Many studies have examined the association between the CYP2E1 Rsa Ι/Pst Ι (rs3813867) polymorphism gene polymorphisms and lung cancer risk in various populations, but their results have been inconsistent. The PubMed and CNKI database was searched for case–control studies published up to October 2013. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. In this meta‐analysis, we assessed 23 published studies involving comprising 4727 lung cancer cases and 6220 controls of the association between CYP2E1 Rsa Ι/Pst Ι polymorphism and lung cancer risk. For the homozygote c2/c2 and c2 allele carriers (c1/c2 + c2/c2), the pooled ORs for all studies were 0.73(95% CI = 0.62–0.84; P = 0.005 for heterogeneity) and 0.84 (95% CI = 0.77–0.92; P = 0.001 for heterogeneity) when compared with the homozygous wild‐type genotype (c1/c1). In the stratified analysis by ethnicity, the same significantly risks were found among Asians and mixed population for both the c2 allele carriers and homozygote c2/c2. However, no significant associations were found in Caucasian population all genetic models. This updated meta‐analysis suggests that CYP2E1 Rsa Ι/Pst Ι c2 allele is a decreased risk factor for the developing lung cancer among Asians and mixed population.  相似文献   

4.
基于近年来分子系统学研究结果,石竹科无心菜属(Arenaria L.)齿瓣亚属[subgen.Odontostemma(G.Don)Williams]在属水平的地位得以恢复,该亚属中相关物种名也因此被组合至齿瓣无心菜属(Odontostemma Benth.ex G.Don)之中。然而,中国所产道孚无心菜(A.dawuensis A.J.LiQ.Ban)与神农架无心菜(A.shennongjiaensis Z.E.ZhaoZ.H.Shen)在相关处理中被遗漏,故在此给予其新的组合名称:O.dawuense(A.J.LiQ.Ban)G.Yao和O.shennongjiaense(Z.E.ZhaoZ.H.Shen)G.Yao。  相似文献   

5.
Enterovirus 71 (EV71) is an important emerging human pathogen with a global distribution and presents a disease pattern resembling poliomyelitis with seasonal epidemics that include cases of severe neurological complications, such as acute flaccid paralysis. EV71 is a member of the Picornaviridae family, which consists of icosahedral, nonenveloped, single-stranded RNA viruses. Here we report structures derived from X-ray crystallography and cryoelectron microscopy (cryo-EM) for the 1095 strain of EV71, including a putative precursor in virus assembly, the procapsid, and the mature virus capsid. The cryo-EM map of the procapsid provides new structural information on portions of the capsid proteins VP0 and VP1 that are disordered in the higher-resolution crystal structures. Our structures solved from virus particles in solution are largely in agreement with those from prior X-ray crystallographic studies; however, we observe small but significant structural differences for the 1095 procapsid compared to a structure solved in a previous study (X. Wang, W. Peng, J. Ren, Z. Hu, J. Xu, Z. Lou, X. Li, W. Yin, X. Shen, C. Porta, T. S. Walter, G. Evans, D. Axford, R. Owen, D. J. Rowlands, J. Wang, D. I. Stuart, E. E. Fry, and Z. Rao, Nat. Struct. Mol. Biol. 19:424–429, 2012) for a different strain of EV71. For both EV71 strains, the procapsid is significantly larger in diameter than the mature capsid, unlike in any other picornavirus. Nonetheless, our results demonstrate that picornavirus capsid expansion is possible without RNA encapsidation and that picornavirus assembly may involve an inward radial collapse of the procapsid to yield the native virion.  相似文献   

6.
This paper comments on the article “Retinal pulse wave velocity measurement using spectral‐domain optical coherence tomography” by Qian Li et al. The authors propose a method to determine the pulse wave velocity in retinal arteries and veins. This method should enable a noninvasive determination of biomechanical properties of the vessel network, particularly the elasticity of the vessel walls. Although the observations the authors made might seem reasonable at first glance, they are in fact highly surprising and contradictory to theoretical predictions and previously published results.  相似文献   

7.
Red carotenoid colours in birds are widely assumed to be sexually selected quality indicators, but this rests on a very incomplete understanding of genetic mechanisms and honesty‐mediating costs. Recent progress was made by the implication of the gene CYP2J19 as an avian carotenoid ketolase, catalysing the synthesis of red C4‐ketocarotenoids from yellow dietary precursors, and potentially a major mechanism behind red coloration in birds. Here, we investigate the role of CYP2J19 in the spectacular colour diversification of African weaverbirds (Ploceidae), represented by five genera and 16 species: eight red, seven yellow and one without carotenoid coloration. All species had a single copy of CYP2J19, unlike the duplication found in the zebra finch, with high expression in the retina, confirming its function in colouring red oil droplets. Expression was weak or undetected in skin and follicles of pigment‐depositing feather buds, as well as in beaks and tarsi, including those of the red‐billed quelea. In contrast, the hepatic (liver) expression of CYP2J19 was consistently higher (>14‐fold) in seven species with C4‐ketocarotenoid coloration than in species without (including one red species), an association strongly supported by a phylogenetic comparative analysis. The results suggest a critical role of the candidate ketolase, CYP2J19, in the evolution of red C4‐ketocarotenoid colour variation in ploceids. As ancestral state reconstruction suggests that ketocarotenoid coloration has evolved twice in this group (once in Euplectes and once in the Quelea/Foudia clade), we argue that while CYP2J19 has retained its ancestral role in the retina, it has likely been co‐opted for red coloration independently in the two lineages, via increased hepatic expression.  相似文献   

8.
9.
Sex‐determination mechanisms vary both within and among populations of common frogs, opening opportunities to investigate the molecular pathways and ultimate causes shaping their evolution. We investigated the association between sex‐chromosome differentiation (as assayed from microsatellites) and polymorphism at the candidate sex‐determining gene Dmrt1 in two Alpine populations. Both populations harboured a diversity of X‐linked and Y‐linked Dmrt1 haplotypes. Some males had fixed male‐specific alleles at all markers (“differentiated” Y chromosomes), others only at Dmrt1 (“proto‐” Y chromosomes), while still others were genetically indistinguishable from females (undifferentiated X chromosomes). Besides these XX males, we also found rare XY females. The several Dmrt1 Y haplotypes differed in the probability of association with a differentiated Y chromosome, which we interpret as a result of differences in the masculinizing effects of alleles at the sex‐determining locus. From our results, the polymorphism in sex‐chromosome differentiation and its association with Dmrt1, previously inferred from Swedish populations, are not just idiosyncratic features of peripheral populations, but also characterize highly diverged populations in the central range. This implies that an apparently unstable pattern has been maintained over long evolutionary times.  相似文献   

10.
The resolution methods applying (?)‐(4R,5R)‐4,5‐bis(diphenylhydroxymethyl)‐2,2‐dimethyldioxolane (“TADDOL”), (?)‐(2R,3R)‐α,α,α',α'‐tetraphenyl‐1,4‐dioxaspiro[4.5]decan‐2,3‐dimethanol (“spiro‐TADDOL”), as well as the acidic and neutral Ca2+ salts of (?)‐O,O'‐dibenzoyl‐ and (?)‐O,O'‐di‐p‐toluoyl‐(2R,3R)‐tartaric acid were extended for the preparation of 1‐n‐butyl‐3‐methyl‐3‐phospholene 1‐oxide in optically active form. In one case, the intermediate diastereomeric complex could be identified by single‐crystal X‐ray analysis. The absolute P‐configuration of the enantiomers of the phospholene oxide was also determined by comparing the experimentally obtained and calculated CD spectra. Chirality 26:174–182, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

11.
该文报道了内蒙古被子植物菊科(Compositae)和禾本科(Gramineae)的2个新分布记录属,即石胡荽属(Centipeda Loureiro)和扇穗茅属(Littledalea Hemsley);十字花科(Cruciferae)、蔷薇科(Rosaceae)、豆科(Leguminosae)、堇菜科(Violaceae)、伞形科(Umbelliferae)、紫草科(Boraginaceae)、菊科(Compositae)、禾本科(Gramineae)、莎草科(Cyperaceae) 9个科的11个新分布记录种,即裂叶独行菜(Lepidium lacerum C. A.Meyer)、腺粒委陵菜(Potentilla granulosa T. T. YuC. L. Li)、祁连山棘豆(Oxytropis qilianshanica C. W.ChangC. L. Zhang ex X. Y.H. Ohashi)、石生堇菜(Viola rupestris F. W. Schmidt)、河西阿魏(Ferula hexiensis K. M. Shen)、青海齿缘草(Eritrichium medicarpum Y. S. LianJ. Q. Wang)、斑种草(Bothriospermum chinense Bunge)、青藏蒿(Artemisia duthreuil-de-rhinsi Krascheninnikov)、石胡荽[Centipeda minima (Linnaeus)A. BraunAscherson]、寡穗茅(Littledalea przevalskyi Tzvelev)、旋鳞莎草[Cyperus michelianus (Linnaeus)Link]。相关凭证标本存放于内蒙古大学植物标本馆(HIMC)中。  相似文献   

12.
The cytochrome P450 monooxygenases (P450s) catalyze a vast array of oxygenation reactions that can be useful in biocatalytic applications. CYP101J2 from Sphingobium yanoikuyae is a P450 that catalyzes the hydroxylation of 1,8‐cineole. Here we report the crystallization and X‐ray structure elucidation of recombinant CYP101J2 to 1.8 Å resolution. The CYP101J2 structure shows the canonical P450‐fold and has an open conformation in the absence of substrate. Analysis of the structure revealed that CYP101J2, in the absence of substrate, forms a well‐ordered substrate‐binding channel that suggests a unique form of substrate guidance in comparison to other bacterial 1,8‐cineole‐hydroxylating P450 enzymes. Proteins 2017; 85:945–950. © 2016 Wiley Periodicals, Inc.  相似文献   

13.
×Taxodiomeria peizhongii Z. J. Ye, J. J. Zhang et S. H. Pan was regarded as a new intergeneric hybrid between Taxodium mucronatum Tenore (as the female donor) and Cryptomeria fortunei Hooibrenk ex Otto et Dietr (as the male donor). To confirm the authenticity of the intergeneric hybrid, we analyzed the rbcL gene and the internal transcribed spacer (ITS) of 26S‐18S ribosomal RNA gene of the three species using polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) and arbitrarily primed PCR (AP‐PCR), and obtained the following results: i) Taxodiomeria peizhongii had the same RFLP maps of the rbcL gene and the ITS as Taxodium mucronatum, but was different from C. fortunei; ii) a 311‐bp PCR amplification product was obtained in C. fortunei by AP‐PCR of ITS, but was not found in Taxodiomeria peizhongii. Our results have demonstrated that C. fortunei did not provide any genome for Taxodiomeria peizhongii, implying that T. peizhongii is not an intergeneric hybrid between the two species. (Managing editor: Wei Wang)  相似文献   

14.
Genes linked to X or Z chromosomes, which are hemizygous in the heterogametic sex, are predicted to evolve at different rates than those on autosomes. This “faster‐X effect” can arise either as a consequence of hemizygosity, which leads to more efficient selection for recessive beneficial mutations in the heterogametic sex, or as a consequence of reduced effective population size of the hemizygous chromosome, which leads to increased fixation of weakly deleterious mutations due to genetic drift. Empirical results to date suggest that, while the overall pattern across taxa is complicated, systems with male heterogamy show a faster‐X effect attributable to more efficient selection, whereas the faster‐Z effect in female‐heterogametic taxa is attributable to increased drift. To test the generality of the faster‐Z pattern seen in birds and snakes, we sequenced the genome of the lepidopteran silkmoth Bombyx huttoni. We show that silkmoths experience faster‐Z evolution, but unlike in birds and snakes, the faster‐Z effect appears to be attributable to more efficient positive selection. These results suggest that female heterogamy alone is unlikely to explain the reduced efficacy of selection on vertebrate Z chromosomes. It is likely that many factors, including differences in overall effective population size, influence Z chromosome evolution.  相似文献   

15.
A “long‐backed” scenario of hominin vertebral evolution posits that early hominins possessed six lumbar vertebrae coupled with a high frequency of four sacral vertebrae (7:12‐13:6:4), a configuration acquired from a hominin‐panin last common ancestor (PLCA) having a vertebral formula of 7:13:6‐7:4. One founding line of evidence for this hypothesis is the recent assertion that the “Lucy” sacrum (A.L. 288‐1an, Australopithecus afarensis) consists of four sacral vertebrae and a partially‐fused first coccygeal vertebra (Co1), rather than five sacral vertebrae as in modern humans. This study reassesses the number of sacral vertebrae in Lucy by reexamining the distal end of A.L.288‐1an in the context of a comparative sample of modern human sacra and Co1 vertebrae, and the sacrum of A. sediba (MH2). Results demonstrate that, similar to S5 in modern humans and A. sediba, the last vertebra in A.L. 288‐1an exhibits inferiorly‐projecting (right side) cornua and a kidney‐shaped inferior body articular surface. This morphology is inconsistent with that of fused or isolated Co1 vertebrae in humans, which either lack cornua or possess only superiorly‐projecting cornua, and have more circularly‐shaped inferior body articular surfaces. The level at which the hiatus' apex is located is also more compatible with typical five‐element modern human sacra and A. sediba than if only four sacral vertebrae are present. Our observations suggest that A.L. 288‐1 possessed five sacral vertebrae as in modern humans; thus, sacral number in “Lucy” does not indicate a directional change in vertebral count that can provide information on the PLCA ancestral condition. Am J Phys Anthropol 156:295–303, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   

16.
Illicit rac‐MDPV (3,4‐methylenedioxypyrovalerone), manufactured in clandestine labs, has become widely abused for its cocaine‐like stimulant properties. It has recently been found as one of the toxic materials in the so‐called “bath salts,” producing, among other effects, psychosis and tachycardia in humans when introduced by any of the several routes of administration (e.g., intravenous, oral, etc.). The considerable toxicity of this “designer drug” probably resides in one of the enantiomers of the racemate. In order to obtain a sufficient amount of the enantiomers of rac‐MDPV to determine their activity, we improved the known synthesis of rac‐MDPV and found chemical resolving agents, (+)‐ and (–)‐2’‐bromotetranilic acid, that gave the MDPV enantiomers in >96% enantiomeric excess as determined by 1H nuclear magnetic resonance and chiral high‐performance liquid chromatography. The absolute stereochemistry of these enantiomers was determined by single‐crystal X‐ray diffraction studies. Chirality 27:287‐293, 2015. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.  相似文献   

17.
Aims: We have previously shown that the (±)‐[13C]‐pantoprazole breath test is a promising noninvasive probe of CYP2C19 activity. As part of that trial, plasma, breath test indices and CYP2C19 (*2, *3, and *17) genotype were collected. Here, we examined whether [13C]‐pantoprazole exhibits enantioselective pharmacokinetics and whether this enantioselectivity is correlated with indices of breath test. Methods: Plasma (−)‐ and (+)‐[13C]‐pantoprazole that were measured using a chiral HPLC were compared between CYP2C19 genotypes and correlated with breath test indices. Results: The AUC(0‐∞) of (+)‐[13C]‐pantoprazole in PM (*2/*2, n = 4) was 10.1‐ and 5.6‐fold higher that EM (*1/*1or *17, n = 10) and IM (*1/*2or *3, n = 10) of CYP2C19, respectively (P < 0.001). The AUC(0‐∞) of (−)‐[13C]‐pantoprazole only significantly differed between PMs and EMs (1.98‐fold; P = 0.05). The AUC(0‐∞) ratio of (+)‐/(−)‐[13C]‐pantoprazole was 3.45, 0.77, and 0.67 in PM, IM, and EM genotypes, respectively. Breath test index, delta over baseline show significant correlation with AUC(0‐∞) of (+)‐[13C]‐pantoprazole (Pearson's r = 0.62; P < 0.001). Conclusions: [13C]‐pantoprazole exhibits enantioselective elimination. (+)‐[13C]‐pantoprazole is more dependent on CYP2C19 metabolic status and may serve as a more attractive probe of CYP2C19 activity than (−)‐[13C]‐pantoprazole or the racemic mixture. Chirality, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   

18.
《Journal of cellular physiology》2019,234(9):16653-16653
The above article from Journal of Cellular Physiology, “Muscle-derived Satellite Cells for Treating Type 1 Diabetes in Rats (Rattus norvegicus)” by Yu Ren, Hefei Wang, Si Ha, Xingsheng Zhao, Xiao Wang, Yu Lan and Xiaoling Liu published online on 10 January 2018 in Wiley Online Library (wileyonlinelibrary.com), has been withdrawn by agreement between the journal Editor in Chief Gary S. Stein and John Wiley and Sons, Inc. The retraction has been agreed because the authors are not responding to requests to finalize their article for publication in the journal as the Version of Record.  相似文献   

19.
李晓娟  李建秀 《广西植物》2020,40(4):443-451
基于Flora of China采用国际石松类和蕨类植物新分类系统,其水龙骨科(Polypodiaceae)不仅涵盖了秦仁昌分类系统中的水龙骨科(Polypodiaceae) 20多属,而且还包括槲蕨科(Drynariaceae)、鹿角蕨科(Platyceriaceae)等独立的科。水龙骨科(Polypodiaceae)新分类系统种类较多、分类复杂,需要对其合理性和孢粉学在新分类系统中的意义进行新的探讨。该文首次以新分类系统为依据,采用扫描电镜对山东分布的水龙骨科(Polypodiaceae)植物孢子形态及其周壁纹饰亚显微结构进行了系统地观察。结果表明:该科孢子形态为圆肾形,左右对称,具周壁,其周壁纹饰在种内稳定,在亚科、属及种间区别显著。孢粉学研究结果,支持槲蕨亚科、鹿角蕨亚科分别列于水龙骨科下的两个亚科;基于山东假瘤蕨孢子周壁纹饰,并结合叶片形态特征,山东假瘤蕨(Phymatopteris shandongensis J.X.Li et C.Y.Wang)应为一个独立的新种,不宜并入金鸡脚假瘤蕨[Phymatopteris hastata (Thunb.) Pic.Serm.]。依...  相似文献   

20.
曹利民  龙春林   《广西植物》2006,26(2):192-193,191
报道了芋属两种植物的核型,结果如下:异色芋2n=2X=28=18m+10sm,属于“2B”类型;花叶芋2n=2X=28=20m(8sat)+8sm(2sat),属于“2A”类型;花叶芋的核型及两个种之间的核型比较系首次报道。  相似文献   

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