产ESBLs大肠埃希菌整合子及其相关基因盒的研究

目的检测产超广谱β-内酰胺酶（ESBLs）大肠埃希菌中整合子的整合酶及插入的相关基因盒情况,分析整合子对细菌耐药性的影响。方法采用K-B琼脂扩散法对45株临床分离的产ESBLs大肠埃希菌进行药敏试验;应用PCR法检测45株产ESBLs大肠埃希菌Ⅰ类、Ⅱ类和Ⅲ类整合子;对Ⅰ类整合子阳性菌进行整合子相关基因盒检测。结果45株菌中有27株（60．0％）含有Ⅰ类整合子,没有检测到Ⅱ类和Ⅲ类整合子阳性菌。在Ⅰ类整合子阳性菌中,有23株携带Ⅰ类整合子相关基因盒（85．2％）,5种不同的基因盒图谱,片段大小在600～2322bp,分离自同一科室的部分菌株携带大小相同的基因盒;Ⅰ类整合子阳性菌株的耐药率高于整合子阴性的菌株。结论Ⅰ类整合子及整合子相关基因盒在产ESBLs大肠埃希菌株中分布广泛,整合子在细菌耐药中发挥作用。     

新生儿病区产ESBLs大肠埃希菌整合子及其耐药性分析

目的 了解新生儿病区产ESBLs大肠埃希菌整合子的携带情况及其耐药性.方法 采用K-B琼脂扩散法对56株产ESBLs大肠埃希菌进行药敏试验;应用PCR法检测Ⅰ类、Ⅱ类和Ⅲ类整合子;以肠杆菌科重复序列-聚合酶链式反应(ERIC-PCR)进行基因分型.结果 56株产ESBLs大肠埃希菌的Ⅰ类整合子检出率为60.7％,未检出Ⅱ类和Ⅲ类整合子;菌株对庆大霉素、环丙沙星、左氧氟沙星、复方新诺明、头孢唑林、氨曲南、头孢他啶的耐药率差异有统计学意义(P＜0.05),阳性菌株的耐药率高于阴性菌株;56株大肠埃希菌分为45种基因型.结论 Ⅰ类整合子广泛存在于新生儿病区产ESBLs大肠埃希菌并与其耐药性相关.     

产超广谱β-内酰胺酶大肠埃希菌Ⅰ类整合子检测与耐药性关系

目的了解I类整合子在产ESBLs和非产ESBLs大肠埃希菌中分布状况,分析I类整合子在细菌多重耐药中的作用。方法用PCR方法扩增I类整合酶基因,经电泳后检测扩增产物。用2χ检验进行统计学分析,P<0.05为差异有显著性。结果105株大肠埃希菌检出I类整合子46株,检出率为43.8%。I类整合子在产ESBLs菌的检出率为53.4%,明显高于非产ESBLs菌(31.9%),2χ检验,P<0.01。I类整合子阳性菌株多重耐药率为68.8%(33/48),明显高于阴性菌株(33.3%),P<0.05。I类整合子阳性菌株和产ESBLs菌均对青霉素类、喹诺酮类、磺胺类抗生素表现出较高的耐药率。所有菌株均对亚胺培南敏感。结论I类整合子携带与产ESBLs菌株耐药有关,I类整合子阳性菌株对多种抗生素的耐药率大于整合子阴性菌株。     

泌尿系感染产ESBLs大肠埃希菌基因分型

目的 了解深圳市人民医院临床泌尿系感染标本中产ESBLs大肠埃希菌的基因型特点.方法 收集近几年深圳市人民医院临床尿液标本中非重复的产ESBLs大肠埃希菌43株,PCR分别扩增菌株的TEM、SHV、CTX-M基因,阳性株进行DNA测序分型.结果 43株产ESBLs大肠埃希菌中40株CTX-M基因阳性,分别为CTX-M-14型36株,CTX-M-9型2株,CTX-M-15型2株,其中17株CTX-M-14型菌株检出TEM-1基因;所有菌株均未检出SHV基因.结论 本地区致泌尿系感染产ESBLs大肠埃希菌中,CTX-M-14型为主.     

产超广谱β-内酰胺酶细菌耐药性基因型分析

检测我院产超广谱β-内酰胺酶(ESBLs)大肠埃希菌和肺炎克雷伯菌的耐药性和基因型。表型确定临床分离产ESBLs的大肠埃希菌和肺炎克雷伯菌56株,应用PCR基因扩增技术及双脱氧DNA测序方法,分别对TEM、SHV、CTX-M-1、CTX-M-2和CTX-M-9编码基因进行分析。产酶菌株对亚胺培南、美洛培南、阿米卡星、头孢吡肟耐药性较低,对其他16种抗生素耐药性较高。在56株菌株中有50株为CTX-M型,占89%,34株为TEM型(60.7%),20株SHV型(35.7%);其中CTX-M-9型共计39株占78%,CTX-M-1型19株占38%,CTX-M-2型16株占32%。产ESBLs大肠埃希菌和肺炎克雷伯菌的耐药性值得关注,主要临床流行基因型是CTX-M型。     

ESBLs大肠埃希菌和肺炎克雷伯杆菌整合子分布及其与ESBLs基因关系研究

目的研究整合子在院内感染ESBLs大肠埃希菌和肺炎克雷伯杆菌中的分布及其与细菌耐药的相关性,探讨Ⅰ类整合子在ESBLs基因水平转移中的作用及其与ESBLs基因型的关系。方法运用K-B法,纸片扩散法,PCR,接合传递试验、套式PCR、质粒谱分析及DNA测序研究携带耐药基因的Ⅰ类整合子与耐药播散的关系。结果产ESBLs和非产ESBLs菌株中Ⅰ类整合酶扩增阳性例数分别是70例（占66.7%）和22例（占22.4%）,2组整合子阳性率差异有统计学意义（P〈0.01）。整合子阳性组中ESBLs、多重耐药菌均明显高于阴性组。产ESBLs菌株中blaSHV、blaCTX和blaTEM基因与整合子经质粒共同转移的频率分别是79.3%、58.5%和45.1%。结论整合子在产ESBLs大肠埃希菌和肺炎克雷伯杆菌中的分布明显高于非产ESBLs菌株,主要为Ⅰ类整合子,并参与产ESBLs菌株多重耐药性的形成,其中blaSHV基因型与整合子经质粒共同转移的频率高于其他两类基因,提示SHV型酶在浙南地区具有更强的扩散优势。     

肿瘤患者医院感染产ESBLS大肠埃希菌调查及基因分析

目的探讨肿瘤患者医院感染产超广谱β-内酰胺酶(extended spectrum beta-lactamase,ESBLs)大肠埃希菌的临床特点,并分析其基因型特征。方法对2014年3月~2016年10月我院肿瘤患者498株临床标本中分离出的338株产ESBLs大肠埃希菌的临床分布进行分析,并比较产与非产ESBLs菌株对19种抗菌药物的耐药率,同时随机抽取338株中的60株应用聚合酶链反应(polymerase chain reaction,PCR)分别扩增ESBLs基因(TEM、CTX-M和SHV)型别。结果 498株大肠埃希菌中产ESBLs 338株(67.87%),标本类型以尿液标本为多(101株,29.88%),临床科室分布中妇瘤科最多(94株,27.81%)。产与非产ESBLs大肠埃希菌对亚胺培南及美罗培南耐敏感性高(耐药率为零),而产ESBLs大肠埃希菌的耐药率大多数均高于非产ESBLs大肠埃希菌,差异均有统计学意义(P0.05)。PCR扩增后基因测序显示,55株为TEM(91.67%),42株为CTX-M1(70.00%),42株为CTX-M13(70.00%),24株为SHV(40.00%),其中携带2种或2种以上耐药基因的有53株(88.33%)。结论本研究肿瘤患者医院感染产ESBLs大肠埃希菌主要标本以尿液标本为主,重点分布在妇瘤科;基因型以TEM、CTX-M1、CTX-M13型为主,并呈现多重耐药趋势。     

产ESBLs大肠埃希菌和肺炎克雷伯菌呼吸道分离株的基因分型及耐药性分析

目的了解深圳市人民医院大肠埃希菌和肺炎克雷伯菌呼吸道分离株超广谱β-内酰胺酶(ESBLs)的基因型特点及耐药性。方法采用临床实验室标准化协会(CLSI)推荐的表型确证试验筛选出该院呼吸道分离株产ESBLs大肠埃希菌和肺炎克雷伯菌共78株。应用PCR及DNA测序法分析产酶株的TEM、SHV及CTX-M3种β-内酰胺酶基因,用琼脂稀释法测定细菌最低抑菌浓度(MIC)。结果 37株产ESBLs大肠埃希菌中,28株(75.7%)检出CTX-M-14基因,4株(10.8%)检出CTX-M-9基因,其他型较少见。41株肺炎克雷伯菌中,25株(61.0%)检出SHV-12基因,4株(9.8%)检出SHV-11基因,其他SHV型较少。20株(48.8%)检出CTX-M-14基因,5株(12.2%)检出CTX-M-3基因,其他型较少。产ESBL菌株均对亚胺培南敏感,对氨苄西林/舒巴坦的耐药率最高(90%),对其他抗生素有不同程度耐药。结论深圳市人民医院呼吸道分离的产ESBLs大肠埃希菌以CTX-M-14型为主,产酶肺炎克雷伯菌以SHV-12和CTX-M-14型为最常见。     

产ESBLs大肠埃希菌的AmpC基因型分析

目的 了解深圳市人民医院产超广谱β-内酰胺酶(ESBLs)大肠埃希菌合并产AmpC酶的状况及基因型特点.方法 从近几年深圳市人民医院产ESBLs大肠埃希菌临床菌株中,筛选出对头孢西丁耐药菌株51株,PCR分别扩增菌株的TEM、SHV、CTX-M基因,同时应用多重PCR检测菌株的AmpC酶基因,序列测定PCR阳性产物以确定其基因亚型.结果 51株菌中有49株至少检出一种ESBLs或AmpC基因.单ESBLs基因阳性菌株37株(72.5％),单AmpC基因阳性4株(7.8％),合并ESBLs和AmpC基因阳性的8株(15.6％).共有41株(80.4％)含CTX-M-14基因,4株含CTX-M-15,其他基因型ESBLs较少.2株检出两种ESBLs基因;一株同时检三种ESBLs基因.检出AmpC基因的菌株12株,其中10株为DHA-1型,2株为CMY-2型;其中6株DHA-1型及2株CMY-2型菌同时检出CTX-M-14基因.结论 该院头孢西丁耐药产ESBLs大肠埃希菌中大多数为单产ESBLs菌,主要为CTX-M-14型;少数同时产生ESBLs和AmpC酶,AmpC酶以DHA-1型为最常见.     

血流感染大肠埃希菌和肺炎克雷伯菌的ESBLs基因分型

目的 了解深圳市人民医院致血流感染大肠埃希菌和肺炎克雷伯菌超广谱β-内酰胺酶(ESBLs)的检出率及基因型特点.方法 收集来自临床血液培养标本中的大肠埃希菌和肺炎克雷伯菌115株,采用ESBLs表型确证试验检测菌株的ESBLs,应用PCR扩增产ESBLs菌株TEM、SHV和CTX-M基因,并对阳性扩增产物进行DNA测序分型.结果 115株菌中共检出ESBLs阳性38株,检出率为33.0％;其中大肠埃希菌阳性25株,肺炎克雷伯菌阳性13株.25株产酶肠埃希菌中18株检出CTX-M-14基因,3株检出CTX-M-9基因.13株产酶肺炎克雷伯菌均检出SHV型基因,其中SHV-12阳性10株,SHV-2阳性2株,SHV-59阳性1株;该13株产酶菌中10株同时被检出含CTX-M-14或CTX-M-13基因.结论 该院致血流感染大肠埃希菌产ES-BLs以CTX-M-14为最主要基因型,肺炎克雷伯产ESBLs最常见为SHV-12和CTX-M-14型.     

Systematic significance of mature embryo of bamboos

The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.     

Taxonomic status of the species of the green algal genusNeochloris

Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Host plants of someRhinanthoideae (Scrophulariaceae) of eastern North America

Twenty three species in 11 genera were examined in the field to determine hosts. OnlyStriga asiatica andSeymeria cassioides have a narrow host range being restricted to grasses and pines, respectively. These are the only species which cause pronounced and sometimes serious host damage. The other species attach to a great diversity of hosts.     

Apoptotic Regulation of Caspase Activity

Intracellular cysteine aspartate-specific proteases (caspases) play both signaling and effector roles in realizing the program of cell death. Caspases function as proteolytic cascades unique for each cell type and signal triggering apoptosis. All parts of the proteolytic cascades are duplicated and controlled by feedback signals. Amplification cycles between pairs of caspases (the third and the sixth, the ninth and the third, the twelfth and the sixth, and others) help multiply the initial apoptotic signal. The presence of physiological inhibitors of apoptosis that directly interact with caspases creates a multilevel regulatory network of apoptosis in cell. The caspase proteolytic cascades are also regulated by sphingolipid secondary messengers, among them ceramide, sphingosine, and their phosphates. Moreover, an association of the caspase signaling with ubiquitin-dependent proteolysis is shown in cells. In particular, the use of extracellular activators and inhibitors of caspases allows irreversible activation of apoptosis in tumor cells or the prevention of apoptosis in cortical neurons under neurodegenerative diseases.     

Analysis of twin of eyeless regulation during early embryogenesis in Drosophila melanogaster

The Drosophila Pax6 homolog twin of eyeless (toy) is so far the first zygotically expressed gene involved in eye morphogenesis in Drosophila. The study of its expression during embryogenesis is therefore informative of the initial events of eye development in Drosophila. We have analyzed how the initial expression domain of toy at cellular blastoderm is regulated. We show that the three maternal patterning systems active in the cephalic region (the anterior, terminal and dorsal-ventral systems) cooperate with zygotically activated gap genes to shape the initial expression domain of toy. Whereas Bicoid, Dorsal and Torso signaling synergistically act as activators, Hunchback, Knirps and Decapentaplegic act as repressors.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.     

New species of Peruvian Orchidaceae III

Sixteen new species are proposed in the generaAckermania, Dressleria, Epidendrum, Maxillaria, Oncidium, Rodriguezia, Sigmatostalix, andTrigonidium. All new species are illustrated.Maxillaria vittariifolia L. O. Williams is newly recorded for Peru. A key is provided forTrigonidium of Peru.Trigonidium loretoense Schltr. andT. peruvianum Schltr. are lectotypified.     

Interaction of Synthetic Analogues of Natural Chalcones and Flavones with Guanidine

The reaction of chalcones and flavones with guanidine in ethanol results in 2-(2-aminopyrimidinyl-4)-phenols.