老年耐碳青霉烯肺炎克雷伯菌耐药机制及院内高毒力荚膜基因型分布特点

目的探讨老年耐碳青霉烯肺炎克雷伯菌感染的耐药机制,分析承德市中心医院高毒力荚膜基因型的分布特点。方法收集2016年1月至2017年3月间从承德市中心医院收治的老年患者中分离出的耐碳青霉烯肺炎克雷伯菌18株,鉴定菌株和药敏试验;采用改良Hodge试验、EDTA协同试验、Carba NP试验初筛碳青霉烯酶,进一步检测菌株毒力情况,PCR检测耐药基因、荚膜血清型和毒力基因。结果碳青霉烯酶检出Kpc基因6株(33.33%),Ndm基因7株(38.89%);超广谱β-内酰胺酶中Shv检出15株(83.33%),明显高于Ctx-M基因10株(55.56%)、Tem基因7株(38.89%)(P<0.01);AmpC酶中检出DHA基因2株(11.11%)。膜孔蛋白基因检测显示,Ompk36编码基因缺失率明显高于Ompk35(P<0.05);且当Ompk35基因缺失时Ompk36也缺失。荚膜分型显示,K1型4株,K57型2株,未检出K2、5、20及54,未分型12株;rmpA阳性率明显高于Acrobactin(P<0.05);4株K1型肺炎克雷伯菌均携带rmpA基因,其中1株同时携带Acrobactin基因;2株K57型肺炎克雷伯菌均携带rmpA基因;18株耐碳青霉烯肺炎克雷伯菌均携带FimH-1基因。结论老年耐碳青霉烯肺炎克雷伯菌感染的主要耐药机制为携带Kpc和Ndm基因以及超广谱β-内酰胺酶合并膜蛋白缺失;该院Kpc基因荚膜血清型菌株分离率较高,应加以重视。     

宁波地区耐碳青霉烯类高毒力肺炎克雷伯菌的分子生物学特征研究

目的 研究宁波地区耐碳青霉烯类高毒力肺炎克雷伯菌(carbapenem-resistant hypervirulent Klebsiella pneumoniae, CR-hvKP)分子流行特征,为宁波地区CR-hvKP院内防控及临床治疗提供理论依据。方法 从宁波地区3家医院收集150株耐碳青霉烯类肺炎克雷伯菌,用PCR筛选出CR-hvKP;再用PCR检测其耐药基因和毒力基因。结果 150株耐碳青霉烯类肺炎克雷伯菌中检出14株CR-hvKP,占比为9.33%;主要标本类型为血流感染6株和痰液5株;临床科室分布以ICU(5株)为主,其次为呼吸科(3株)和血液科(3株)。14株CR-hvKP拉丝试验阳性,荚膜血清型以K2为主,整合子均为intI1型;碳青霉烯类耐药基因以KPC-2为主,且发现3株同时携带KPC-2和NDM-1耐药基因;14株CR-hvKP均携带rmpA、kpn、entB、wabG、ureA、fimH毒力基因,其中2株aerobactin基因阳性。结论 宁波地区出现的CR-hvKP以K2荚膜型为主,耐药情况严重,且同时携带耐药及毒力基因,提示临床须合理使用抗生素,加强耐药监测及院感防控,以减少CR-hvKP的传播。     

血流感染高致病性肺炎克雷伯菌毒力因子及分子分型特点分析

目的研究血流感染高致病性肺炎克雷伯菌的毒力基因和基因分型特点。方法采用PCR方法检测临床分离株血流感染高致病性肺炎克雷伯菌的高毒力基因,并进行荚膜血清型和ST分型;采用微量肉汤稀释法通过BD Phoenix全自动细菌鉴定/药敏系统对分离菌株进行药敏试验;应用加克拉维酸复合药(头孢他啶/克拉维酸或头孢噻肟/克拉维酸)与单药(头孢噻肟或头孢他啶)的药敏纸片组合进行肺炎克雷伯菌产ESBLs的表型确证试验。结果 115株血流感染肺炎克雷伯菌临床分离株分为高毒力肺炎克雷伯菌(Hvkp,占43.48%,50/115)和非Hvkp(non-HvKP,占56.52%,65/115)。与non-HvKP相比,HvKP更容易表现为高黏液性表型(44.00%VS 6.15%,P0.01),且普遍携带rmpA(98.00%VS 4.61%,P0.01)、rmpA2(50.00%VS 3.08%,P0.01)、wcag(24.00%VS 2.15%,P0.05)毒力基因。HvKP常为K1、K2荚膜血清型,non-HvKP常为K-nontypable血清型。本组血流感染肺炎克雷伯菌主要流行ST型别为ST23、ST65、ST37,其中Hvkp流行型为ST23、ST65和ST86。Hvkp对常用抗生素的敏感性好于non-HvKP,其中发现产ESBLs耐药hvKP菌株4株。结论血液感染高毒力肺炎克雷伯菌易表现为高黏液性表型且普遍携带rmpA毒力基因,因此应注意检测肺炎克雷伯菌黏液性状、荚膜血清型、毒力基因以及ST分型,以利于hvkp感染的识别。     

多重耐药HvKP菌株临床感染分布及耐药机制

目的探讨高毒力肺炎克雷伯菌新型变种(Hv KP)临床感染分布和耐药机制。方法肺炎克雷伯菌180株为实验菌株并筛选Hv KP菌株;多位点序列分析和ERIC-PCR检测Hv KP菌株的分子流行病学特征;检测实验菌株对常用抗菌药物的敏感性,梅里埃ETEST药敏纸条检测美罗培南和厄他培南的MIC值;PCR和基因测序检测耐药基因型、血清荚膜分型、毒力基因;黏液丝试验检测菌株高黏液型表型。结果共分离出11株Hv KP菌株,其中医院获得性Hv KP菌株感染率明显高于社区获得性感染率(P<0.05);明确Hv KP菌株感染前碳青霉烯类使用率明显高于其他类抗生素(P<0.05)。11株Hv KP中检出5种ERIC-MLST克隆分型,主要为A/ST23、B/ST263分型。PCR和测序显示,广谱β-内酰胺酶基因中,9株携带bla TEM-1、5株携带bla CTX-M-3、5株携带bla CTX-M-14、3株携带bla SHV-12;质粒介导喹诺酮类耐药基因中,8株携带qnr A1、6株携带qnr B4、6株携带qnr S4、2株携带acc-Ib-cr。荚膜血清型为K1的10株、K2的1株。毒力基因中mag A、rmp A、产气菌素的检出率明显高于其他毒力基因(P<0.05)。结论 A/ST23、B/ST263型分子克隆是引发多重耐药Hv KP菌株的机制之一且存在强毒性血清型和多种毒力基因。     

引起肝脓肿的肺炎克雷伯菌毒力基因检测及同源性分析

目的探讨院内肝脓肿肺炎克雷伯菌荚膜血清型及毒力基因携带情况,且对这些菌株进行同源性分析。方法收集佳木斯大学附属第一医院2018年10月-2019年10月从肝脓肿患者分离出的肺炎克雷伯菌非重复菌株26株,且这些菌株经Vitek-2 Compact全自动微生物分析仪鉴定是肺炎克雷伯菌,对这些菌株进行拉丝试验,使用PCR方法检测这些菌株的主要荚膜血清型及相关毒力基因;并通过多位点序列分型技术分析菌株同源性。计数资料组间比较采用Fisher’s确切检验。结果 26株肝脓肿肺炎克雷伯菌拉丝试验阳性率达100%;检测出K1型(17株)、K2型(5株)、K5型(1株)、K57型(1株)、未知血清型2株。毒力基因rmpA、aero、ureA阳性率达100%(26/26);uge、mrkD阳性率为96. 2%(25/26);fimH阳性率为80. 8%(21/26);iucB阳性率为731%(19/26);wcaG、magA、kfu阳性率为65. 4%(17/26);allS阳性率为61. 5%(16/26);kpn阳性率为30. 8%(8/26);iroNB阳性率为7. 7%(2/26);未检出cf29a基因;wcaG、magA、allS只在K1血清型中检出;uge未在K57血清型菌中检出。多位点序列分型发现ST23型(17株)、ST86型(3株)、ST65型(2株)、ST1934型(2株)、ST485型(1株)、ST592型(1株)。结论本实验菌株以K1、K2血清型为主,ST23型为本院主要感染序列型。     

携带wcaG毒力基因ST19产酸克雷伯菌致白血病患者死亡的分析

目的了解1例高黏液表型(HMV)产酸克雷伯菌致白血病患者的死亡原因。方法采用Vitek 2Compact全自动微生物仪进行菌株鉴定及药敏试验,黏液丝试验检测HMV表型,PCR方法及基因测序检测主要的高毒力荚膜血清型基因(K1、K2、K5、K20、K54、K57)和毒力基因(rmpA、wcaG、allS、kfu、aerobactin、mrkD、fimH、uge、wabG、cf29a),多位点序列分析(MLST)对该菌株进行分子分型。结果白血病患者血液及肺组织分离株均为产酸克雷伯菌,MLST分型为同一型ST19,该菌株对所测药物均敏感,具有高黏液表型,只检测到wcaG毒力基因,其他毒力基因和所测荚膜血清型基因均阴性。结论携带wcaG毒力基因是ST19产酸克雷伯菌致白血病患者死亡的主要原因,应引起临床关注。     

浙江省首次检出1株携带NDM-1基因的肺炎克雷伯菌

目的对浙江省不同地区上送的临床分离株进行NDM-1基因筛检,初探浙江省NDM-1基因携带菌阳性菌存在现状。方法应用TaqMan-MGB荧光定量PCR方法对2013年度收集的所有临床株进行NDM-1基因筛检;利用普通PCR方法对阳性株进行NDM-1基因测序、MLST分型及其它30种耐药基因检测;使用VITEK 2Compact高级专家系统对阳性株进行微生物鉴定与耐药表型MIC测试;采用改良Hodge实验及亚胺培南-EDTA双纸片法协同试验,分别对阳性株进行碳青霉烯酶及金属β-内酰胺酶检测。结果经对1 450株菌株进行筛检,仅从1株来自疑似病毒腹泻11月大幼儿患者粪便中分离的肺炎克雷伯菌中检出该基因,基因序列同源性为100%,该菌MLST序列型为ST1416,产碳青霉烯酶及金属β-内酰胺酶,对Levofloxacin、Trimethoprim/Sulfa敏感,对Ciprofloxacin中敏,但对其他18种所检药物均显示耐药,另携带SHV、CTX、DHA、TEM、CMY2、IMP、GES、GIM、OXA-48、SPM、AmpC、aadA1、aacA4、aphA1共14种耐药基因,结果表明该菌株的耐药表型与基因型较为符合。结论本次从肠杆菌科肺炎克雷伯菌中检出NDM-1基因,应为浙江省首次报道,鉴于肠杆菌科细菌耐药速率传播更快,警示相关部门应重视并加强对NDM-1基因携带菌的监测与筛查。     

一株产DHA-1型质粒AmpC酶肺炎克雷伯菌的耐药基因鉴定及药物敏感性测定

目的对一株头孢西丁耐药肺炎克雷伯菌进行耐药基因鉴定及药物敏感性测定。方法对临床分离的一株头孢西丁耐药肺炎克雷伯菌,采用PCR扩增及测序,检测细菌的耐药基因特性,接合实验验证质粒的传递性,等电聚焦电泳（IEF）测定细菌β-内酰胺酶的等电点。结果该株肺炎克雷伯菌产生TEM-1、DHA-1和SHV-12三种3-内酰胺酶,其耐药基因blaDHA-1可通过质粒传递。结论我院已发现同时携带DHA-1型质粒AmpC酶及SHV-12型ESBL的肺炎克雷伯菌;临床应及时准确进行鉴定及药敏实验,为合理使用抗菌药物提供依据。     

成都市人源沙门菌基因组特征分析

目的 基于全基因组测序技术,探究成都市人源沙门菌的基因组特征, 为监测与预防沙门菌感染提供资料。方法 收集35株成都市人源沙门菌(分离自腹泻患者粪便)进行全基因组测序。根据测序数据,进行血清型预测、耐药基因及可移动遗传元件预测、毒力因子注释及分布分析。结果 35株沙门菌分离株经全基因组测序,共预测到5种血清型,包括15株I 4,[5],12:i:-沙门菌(13株为ST34、2株为新ST型)、12株鼠伤寒沙门菌(ST19)、5株肠炎沙门菌(ST11)、2株德比沙门菌(ST40)与1株火鸡沙门菌(ST463)。35株沙门菌分离株共预测到10类42种不同的耐药基因,其中氨基糖苷类aac(6')-Iaa携带率为100%(35/35)。I 4,[5],12:i:-沙门菌的耐药基因、质粒及插入序列数目及种类多于其他血清型菌株。I 4,[5],12:i:-、鼠伤寒沙门菌和肠炎沙门菌的毒力因子数目大于其他血清型菌株。部分鼠伤寒沙门菌有更高的毒力质粒、质粒编码菌毛和血清抗性毒力因子分布。结论 成都市人源沙门菌不同血清型菌株之间耐药基因、可移动遗传元件、毒力因子分布差异明显,值得在转录组、蛋白组进一步探究其耐药与毒力机制。     

不同来源金黄色葡萄球菌的全基因组序列分析北大核心CSCD

目的了解不同来源金黄色葡萄球菌(简称金葡菌)的全基因组序列基本特征,探究菌株的分子分型、耐药基因型、毒力及其遗传进化关系。方法应用solexa高通量测序技术对10株医源性和食源性代表株金葡菌进行全基因组测序,以此进行多位点序列分型(multilocus sequence typing,MLST)、金葡菌a蛋白(Staphylococcus aureus protein A,spa)基因分型分析,并比较分析不同菌株基因组中携带耐药基因和毒力因子,筛选核心基因,构建系统进化树。结果10株金葡菌染色体基因组大小相似,均为2.7Mbp,包含有2486~2648个基因不等,平均长度约为887bp。耐药基因注释分析显示9株甲氧西林敏感金葡菌(MSSA)携带的耐药基因少于另一株耐甲氧西林金葡菌(MRSA)。尽管在不同菌株基因组之间的毒力因子数量无显著区别,但不同菌株存在的毒力因子却不同,食品来源金葡菌基因组携带1~4种数量不等的肠毒素基因。进化树分析显示不同来源金葡菌位于不同进化分支,2株为ST8型的MSSA和MRSA进化亲缘性较高,属于同一进化分支内。结论获得10株不同来源金葡菌的全基因组序列数据,并证实食源性或医院来源金葡菌为了适应不同生存环境,通过不同分子进化机制,获得不同耐药基因和毒力因子,形成菌株特定的分子遗传特征,可为金葡菌的分子流行病学和致病性机制研究提供参考依据。     

Novel association of HLA-haplotypes with primary sclerosing cholangitis (PSC) in a southern European population

AIMS: In patients with with primary sclerosing cholangitis we investigated the major histocompatibility complex (MHC) genes and mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. METHODS: In 64 PSC patients and 183 normal controls of the same population (Northern Italy), allelic polymorphisms at the DNA level were investigated in MHC region genes: HLA-DRB1, HLA-DQB1 and HLA-B, tumour necrosis factor A (TNFA), and in CFTR gene, with polymerase chain reaction-based methodologies. RESULTS: Frequencies of DRB1*01, DQA1*0101, DQB1*0102 (14 vs. 8%, p<0.05), DRB1*16, DQA1*0102, DQB1*0502 (8 vs. 3%, p<0.025) and DRB1*04, DQA1*03, DQB1*0301 (10 vs. 4%, p<0.005) haplotypes were more elevated in PSC patients. The frequency of patients positive for HLA DRB1*01, *1601 or *04 related haplotypes was significantly increased (32 vs. 14%, p<0.00025). DRB1*07, DQA1*0201, DQB1*02 haplotype frequency was significantly decreased (4 vs. 15%, p<0.001). After removing HLA-DRB1*01, *1601, *04 related haplotype sharing patients, HLA-DRB1*03, DQA1*0501, DQB1*02 haplotype frequency was significantly increased (32 vs. 14%, p<0.01). TNFA2 allele frequency was significantly increased in PSC patients (23 vs. 14%, p<0.025), as well as the TNFA2 homozygous genotype (9 vs. 0.5%, p=0.0013). No mutations were found on the CFTR gene and the allelic frequency of the 5T polymorphism in intron 8 was not increased. CONCLUSION: These data suggest that the role of genes in the HLA region is relevant, but not necessarily disease-specific and it might be different in populations with divergent ancestries.     

Olfactory receptor genes expressed in distinct lineages are sequestered in different nuclear compartments

The olfactory system translates a vast array of volatile chemicals into diverse odor perceptions and innate behaviors. Odor detection in the mouse nose is mediated by 1,000 different odorant receptors (ORs) and 14 trace amine-associated receptors (TAARs). ORs are used in a combinatorial manner to encode the unique identities of myriad odorants. However, some TAARs appear to be linked to innate responses, raising questions about regulatory mechanisms that might segregate OR and TAAR expression in appropriate subsets of olfactory sensory neurons (OSNs). Here, we report that OSNs that express TAARs comprise at least two subsets that are biased to express TAARs rather than ORs. The two subsets are further biased in Taar gene choice and their distribution within the sensory epithelium, with each subset preferentially expressing a subgroup of Taar genes within a particular spatial domain in the epithelium. Our studies reveal one mechanism that may regulate the segregation of Olfr (OR) and Taar expression in different OSNs: the sequestration of Olfr and Taar genes in different nuclear compartments. Although most Olfr genes colocalize near large central heterochromatin aggregates in the OSN nucleus, Taar genes are located primarily at the nuclear periphery, coincident with a thin rim of heterochromatin. Taar-expressing OSNs show a shift of one Taar allele away from the nuclear periphery. Furthermore, examination of hemizygous mice with a single Taar allele suggests that the activation of a Taar gene is accompanied by an escape from the peripheral repressive heterochromatin environment to a more permissive interior chromatin environment.The mammalian olfactory system possesses enormous discriminatory power (1, 2). It can distinguish a multitude of volatile odorants as having specific odors as well as elicit innate behavioral or physiological responses (3–6).Mice have 1,000 different odorant receptors (ORs), each expressed by a unique subset of olfactory sensory neurons (OSNs) scattered within one zone of the nasal olfactory epithelium (OE) (7–11). ORs are used in a combinatorial manner to detect odorants, a strategy that explains how myriad odorants can be discriminated (12).However, the OE also contains 14 trace amine-associated receptors (TAARs), whose expression patterns resemble those of ORs (13). Like ORs, TAARs are evolutionarily conserved in vertebrates, suggesting that they may serve a distinct function. Ligands found thus far for TAARs are volatile amines, including several in mouse or predator urine (5, 14, 15). Ligands for a few mouse, fish, and human TAARs elicit aversive or attractive behaviors in their respective species, hinting at a conserved ability of TAARs to stimulate innate responses of potentially adaptive significance (5, 6, 14, 16, 17).If this is the case, one might envisage OSNs expressing TAARs as a distinct neuronal subgroup capable of conveying signals to the brain that elicit specific behaviors. Consistent with this idea, some OSNs appear biased to express TAARs. OR-expressing OSNs are thought to randomly select one odorant receptor (Olfr) allele for expression, but choose a second Olfr allele to express if the first one fails to produce a functional protein (18–20). A high proportion of OSNs that express a mutated Taar gene also express a functional Taar allele, suggesting similar mechanisms for Olfr and Taar “gene choice,” but one tailored to Taars (21, 22).What regulatory mechanisms dictate TAAR versus OR expression in OSNs? How do OSNs slated to express TAARs avoid expressing ORs when there are about 70 times as many Olfr as Taar alleles? Another question concerns the regulation of gene expression within the Taar family. Whereas Olfr genes are found in clusters at multiple loci on most chromosomes (11), Taar genes are clustered at a single chromosomal locus (23). Like Olfr genes, different Taar genes can be expressed in different spatial domains within the OE (13, 21). The differential expression suggests the existence of additional gene regulatory mechanisms that act at the level of the Taar gene locus, but remain to be elucidated.Here, we investigated Taar gene choice within the Taar locus as well as at the level of nuclear architecture. At the level of the Taar locus, we find evidence for fine scale mechanisms that bias Taar gene choice to subsets of Taar genes expressed in different OE domains. At the level of the nucleus, we find a striking difference between the intranuclear compartments containing Taar versus Olfr genes. In sharp contrast to Olfr genes, which reside primarily in the nuclear interior near large heterochromatin aggregates (24, 25), Taar genes preferentially localize to a thin rim of heterochromatin adjacent to the nuclear envelope. Our studies further indicate that the activation of a Taar allele involves an escape from this peripheral heterochromatin rim to a more interior location, a shift likely to remove the Taar allele from a repressive heterochromatin environment to one permissive for Taar gene expression.     

1号染色体上高血压病易感基因的定位研究(大家系同胞对分析)

目的　定位和筛查高血压病 (EH)的易感基因位点。方法　应用染色体多点扫描策略和扩增片段长度多态性分析技术 ,在 1号染色体上选择 11个短串联重复序列 (shorttandemrepeat,STR) ,对一个典型的EH大家系进行同胞对连锁分析。结果　D1S165 6位点的统计量t值为 1.68,具有显著统计学意义 (t>1.64 )。统计每一位点在同胞组中共享最多的等位片段所占比例 ,观察到D1S165 6位点的 15 4bp等位片段与EH患者伴随频率最高 ,占 5 8.4 %。进一步以此片段作为特定因子进行传递不平衡分析 ,传递 15 4bp等位基因的频率显著高于期望值 (χ2td=6.0 0 ,P <0 .0 5 ) ,表明15 4bp片段在传递过程中存在显著连锁不平衡。结论　 1号染色体上的一个遗传标记 (D1S165 6)与EH连锁 ,提示该位点的附近可能存在EH的易感基因 ,这一结果为EH易感基因的进一步定位提供了重要的资料。     

宁波地区海产品及环境中副溶血弧菌主要毒力及耐药性分析

目的了解浙江省宁波地区海产品和环境中副溶血弧菌主要毒力和耐药性。方法采用生化反应、抗菌药物敏感性试验及PCR方法对分离的宁波地方副溶血弧菌进行毒力及耐药性测定。结果 90株分离株中,耐热直接溶血素基因（tdh）阳性率为2.2%,与神奈川溶血表型（KP,Kanagawa phenomenon）一致,但在tdh＋和KP阳性的分离株中未检测到Ⅲ型分泌系统2（T3SS2）;trh与ureC基因携带率分别为20.0%和12.2%,而在11株trh＋-ureC＋菌株中未显示尿素酶表型阳性,2株尿素酶阳性的菌株未携trh或ureC基因;Ⅵ型分泌系统的携带率为17.8%。所有的分离株对氟喹诺酮类、氯霉素类、四环素类药物敏感;72%以上分离株对青霉素类、磺胺类及氨基糖苷类中链霉素和卡那霉素耐药;分离株中至少耐2种药物,最多耐10种药物,超过82%的分离株对6种以上药物耐药。耐药基因tetB的检出率为0,bla TEM、sul2和strB的携带率分别为91.7%、16.7%和43.3%。结论宁波地区相当比例的菌株携带毒力,并呈现不同程度耐药。     

Dissecting the genetics of Type 1 diabetes: relevance for familial clustering and differences in incidence

A combination of genetic and environmental factors is most likely the cause of Type 1 diabetes. Results from twin data, familial clustering of the disease and difference in incidence according to ethnicity infer the presence of specific disease genes. The genetic component of Type 1 diabetes cannot be classified according to a classical model of inheritance but is due to an interaction between different genes and environmental factors. The major genes are within the HLA region that are responsible for 40% of the genetic susceptibility, although other genes are important (non-HLA genes). To date, more than 10 specific loci have been localized on different chromosomes. The gene involved has been characterized only for two of such loci, IDDM1 and IDDM2, while in the other cases the presence of some susceptibility genes can be envisaged and their identification represents the goal of genetic research in coming years. Fine mapping of the loci will certainly increase our understanding of the genetics of Type 1 diabetes; the limitation in detecting some of the remaining genes by linkage studies can be overcome by association studies. That is possible via the collection of a large number of affected families (over 1000) in homogeneous populations. © 1998 John Wiley & Sons, Ltd.     

大肠癌组织APC/MCC基因杂合的缺失

目的研究大肠癌ＡＰＣ／ＭＣＣ基因杂合缺失的作用。方法采用ＰＣＲ技术，并配合限制性片段长度多态现象（ＲＦＬＰ）分析，对４１例外科手术切除大肠癌组织ＡＰＣ／ＭＣＣ基因杂合缺失（ＬＯＨ）进行检测。结果在大肠癌４１例中ＡＰＣ基因属信息个体者２５例，检出ＬＯＨ７例，占２８．０％；ＭＣＣ基因属信息个体者２２例，检出ＬＯＨ８例，占３６．４％。若将ＡＰＣ和ＭＣＣ基因进行综合分析，则信息个体者３６例，检出ＬＯＨ１４例，占３８．９％。ＡＰＣ和ＭＣＣ基因的ＬＯＨ与肿瘤大小、组织学类型、浆膜浸润、淋巴结转移及Ｄｕｋｅｓ分期无关（Ｐ＞０．０５）。结论ＡＰＣ和ＭＣＣ基因ＬＯＨ是大肠癌的常见改变     

A genome-wide association study of alcohol dependence

Excessive alcohol consumption is one of the leading causes of preventable death in the United States. Approximately 14% of those who use alcohol meet criteria during their lifetime for alcohol dependence, which is characterized by tolerance, withdrawal, inability to stop drinking, and continued drinking despite serious psychological or physiological problems. We explored genetic influences on alcohol dependence among 1,897 European-American and African-American subjects with alcohol dependence compared with 1,932 unrelated, alcohol-exposed, nondependent controls. Constitutional DNA of each subject was genotyped using the Illumina 1M beadchip. Fifteen SNPs yielded P < 10⁻⁵, but in two independent replication series, no SNP passed a replication threshold of P < 0.05. Candidate gene GABRA2, which encodes the GABA receptor α2 subunit, was evaluated independently. Five SNPs at GABRA2 yielded nominal (uncorrected) P < 0.05, with odds ratios between 1.11 and 1.16. Further dissection of the alcoholism phenotype, to disentangle the influence of comorbid substance-use disorders, will be a next step in identifying genetic variants associated with alcohol dependence.     

What exists beyond cagA and vacA? Helicobacter pylori genes in gastric diseases

Helicobacter pylori(H. pylori) infection is present in more than half the world's population and has been associated with several gastric disorders, such as gastritis, peptic ulceration, and gastric adenocarcinoma.The clinical outcome of this infection depends on host and bacterial factors where H. pylori virulence genes seem to play a relevant role. Studies of cag A and vac A genes established that they were determining factors in gastric pathogenesis. However, there are gastric cancer cases that are cag A-negative. Several other virulence genes have been searched for, but these genes remain less well known that cag A and vac A. Thus, this review aimed to establish which genes have been suggested as potentially relevant virulence factors for H. pylori-associated gastrointestinal diseases. We focused on the cag-pathogenicity island, genes with adherence and motility functions, and ice A based on the relevance shown in several studies in the literature.     

Carcinoembryonic antigen-related cell adhesion molecule 16 interacts with alpha-tectorin and is mutated in autosomal dominant hearing loss (DFNA4)

We report on a secreted protein found in mammalian cochlear outer hair cells (OHC) that is a member of the carcinoembryonic antigen-related cell adhesion molecule (CEACAM) family of adhesion proteins. Ceacam16 mRNA is expressed in OHC, and its protein product localizes to the tips of the tallest stereocilia and the tectorial membrane (TM). This specific localization suggests a role in maintaining the integrity of the TM as well as in the connection between the OHC stereocilia and TM, a linkage essential for mechanical amplification. In agreement with this role, CEACAM16 colocalizes and coimmunoprecipitates with the TM protein α-tectorin. In addition, we show that mutation of CEACAM16 leads to autosomal dominant nonsyndromic deafness (ADNSHL) at the autosomal dominant hearing loss (DFNA4) locus. In aggregate, these data identify CEACAM16 as an α-tectorin-interacting protein that concentrates at the point of attachment of the TM to the stereocilia and, when mutated, results in ADNSHL at the DFNA4 locus.