口腔扁平苔藓患者白色念珠菌分离株的毒力与遗传特征初探

目的　研究健康人和口腔扁平苔藓 (OLP)患者口腔白色念珠菌分离株的遗传特征及其与毒性特征的相关性。方法　应用随机扩增片段多态性分析法 (RAPD)分析来自于健康人 (2 6株 )、糜烂型OLP患者 (6 2株 )及非糜烂型OLP患者 (2 4株 )共 112株白色念株菌的基因型特征 ,并采用蛋黄培养基沉淀环面积测量法及颊细胞黏附实验法检测这些菌株的磷脂酶活性和颊细胞黏附力 ,以了解菌株基因型特征与毒力特征的相关性。结果　采用的RAPD分析法可大致将所有白色念珠菌分离株分为A、B、C、D 4种基因型 ;而健康对照组、糜烂型OLP和非糜烂型OLP组的白色念珠菌分离株的基因型构成均具有差异 ,其中 ,健康对照组以B、D型为主 ,糜烂型OLP组以A、C型为主 ,非糜烂型OLP组以A、D型为主 ;对 4种基因型白色念珠菌的黏附力的比较显示 ,最高为A型 ,其次为C型 ,最后为B、D型 ;对 4种基因型白色念珠菌的磷脂酶活性的比较显示 ,A、C型较高 ,其次为B型 ,最后为D型。结论　某些具有特定基因型的高毒力白色念珠菌分离株与OLP的发生发展可能相关。     

口腔扁平苔藓患者白色念珠菌分离株的颊细胞粘附力研究

的　研究健康人和口腔扁平苔藓患者口腔白色念珠菌分离株的颊细胞粘附力。方法　应用颊细胞粘 附实验法,比较来自于健康人(26株)、糜烂型口腔扁平苔藓患者(62株)以及非糜烂型口腔扁平苔藓患者(24株)共 112株白色念珠菌对人颊细胞粘附力的大小。结果　糜烂型口腔扁平苔藓患者组的白色念珠菌分离株的平均粘附 数较健康对照组高(P<0·05),说明糜烂型口腔扁平苔藓患者组白色念珠菌分离株的颊细胞粘附力高于健康对照 组。结论　糜烂型口腔扁平苔藓患者组的白色念珠菌分离株与健康对照组相比,具有不同的毒性特征,白色念珠 菌与糜烂型口腔扁平苔藓发生发展可能相关。     

慢性牙周炎者龈下酵母菌的检出及毒力初探

目的:研究慢性牙周炎患者龈下酵母菌的检出及白色念珠菌分离株的蛋白酶和磷脂酶活性。方法:采用真菌分离培养鉴定法,考察慢性牙周炎患者龈下酵母菌的检出及其分布;应用BSA-琼脂培养基及蛋黄培养基分别测量白色念珠菌分离株蛋白酶和磷脂酶活性大小。结果:43例慢性牙周炎者龈下酵母菌检出率为30.2%,其中白色念珠菌占46.2%;患者是否携带酵母菌与性别、年龄、吸烟、牙周袋深度、龈沟出血指数无关;白色念珠菌分离株中蛋白酶高毒力株占53.3%;深牙周袋组白色念珠菌磷脂酶活性明显高于浅牙周袋组,P=0.00<0.01。结论:慢性牙周炎患者牙周袋内白色念珠菌的毒力特征与CP的发生和发展可能相关。     

头颈部癌放疗患者口腔念珠菌毒性变化的体外研究

目的从口腔念珠菌本身毒性变化的角度探讨头颈部癌放疗患者口腔念珠菌的致病机理。方法通过体外实验从磷脂酶活性、溶血性和对颊黏膜上皮细胞的粘附力三方面比较放疗对口腔念珠菌致病性改变的影响。结果放疗后口腔念珠菌致病菌和定植菌与正常口腔念珠菌三者之间,磷脂酶活性和粘附力的差异无统计学意义(P<0.05);放疗后口腔念珠菌致病菌的溶血性较放疗后口腔念珠菌定植菌及正常口腔念珠菌强,差异有统计学意义(P<0.05);放疗后口腔念珠菌定植菌与正常口腔念珠菌之间的溶血性改变差异无统计学意义(P<0.05)。结论头颈部癌放疗患者口腔念珠菌的溶血性改变可能是其口腔念珠菌病易感的致病因素之一。     

HIV感染者口腔白色念珠菌磷脂酶活性的体外研究

目的探讨HIV感染者口腔白色念珠菌单一感染与混合感染时分离株的磷脂酶活性,及其与宿主机体免疫力（用CD4细胞计数表示）的关系。方法40株白色念珠菌按单一感染或是否与其他念珠菌混合感染及CD4细胞计数的高低进行分组,采用卵黄培养基法检测其磷脂酶活性（Pz值）,并进行析因方差分析。结果40株白色念珠菌体外磷脂酶活性均为阳性（100%）,白色念珠菌单一和混合感染的平均Pz值分别为0.6007和0.5142（P〈0.05）,CD4细胞多于200个/mm3和CD4细胞少于200个/mm3时白色念珠菌的平均Pz值分别为0.5460和0.5688（P〉0.05）。结论作为白色念珠菌的重要毒力因子,HIV感染者口腔白色念珠菌磷脂酶活性与是否有其他念珠菌混合感染有关,而与机体免疫力无关。     

环氧化酶-2与口腔黏膜癌变关系的研究进展

近年来研究者们对环氧化酶-2与口腔黏膜癌前损害及口腔鳞状细胞癌的关系进行了一系列体内外研究,结果发现环氧化酶-2参与口腔黏膜癌变的发生发展,且与口腔癌前损害的转归和口腔鳞癌的预后有着密切的关系.在动物实验及鳞癌细胞系的研究中均发现环氧化酶-2抑制剂能有效阻止口腔癌前损害的恶性转化,预防和治疗口腔鳞癌.进一步研究发现环氧化酶-2和其抑制剂可通过影响细胞的生长、凋亡、运动和粘附及血管生成和机体免疫等途径参与癌变进程.该酶有望成为口腔癌前损害及口腔鳞癌防治研究的一个新靶点.     

环氧化酶-2与口腔黏膜癌变关系的研究进展

近年来研究者们对环氧化酶-2与口腔黏膜癌前损害及口腔鳞状细胞癌的关系进行了一系列体内外研究，结果发现环氧化酶-2参与口腔黏膜癌变的发生发展，且与口腔癌前损害的转归和口腔鳞癌的预后有着密切的关系。在动物实验及鳞癌细胞系的研究中均发现环氧化酶-2抑制剂能有效阻止口腔癌前损害的恶性转化，预防和治疗口腔鳞癌。进一步研究发现环氧化酶-2和其抑制剂可通过影响细胞的生长、凋亡、运动和粘附及血管生成和机体免疫等途径参与癌变进程。该酶有望成为口腔癌前损害及口腔鳞癌防治研究的一个新靶点。     

白色念珠菌感染与口腔癌的关系

口腔癌是头颈部最常见的癌症之一,严重影响患者生存质量和生活水平。白色念珠菌是口腔中最常见的机会性致病真菌,当宿主免疫功能低下时表现出致病性,容易引起念珠菌感染。近年来研究发现白色念珠菌感染与口腔癌关系密切,本文对口腔癌患者白色念珠菌感染的流行病学特点,以及白色念珠菌感染对口腔癌发生发展的影响及其机制研究进行综述。通过回顾相关文献发现:口腔癌患者白色念珠菌感染风险增加,白色念珠菌感染可能通过损伤口腔上皮、产生致癌物质、触发慢性炎症及辅助性T细胞17免疫反应等机制促进口腔癌的发生发展。然而目前这些机制的研究仍比较表浅,缺乏充足的直接证据,未来仍需进行大量研究,以期进一步明确白色念珠菌的促癌机制,为防治口腔癌提供新思路。     

miR-630在OSF及伴OSF的OSCC组织中的表达研究

目的:研究微小RNA-630 (miR-630)在口腔黏膜下纤维性变(OSF)和伴OSF口腔鳞癌组织中的表达,初步探讨miR-630在口腔鳞癌及OSF癌变发生发展过程中的作用.方法:采用实时荧光定量PCR (real-time q-PCR)检测13例正常黏膜组织(A1组)、12例OSF组织(A2组)、22例伴OSF口腔癌癌旁组织(A3组)及相对应伴OSF口腔癌组织(A4组)中miR-630表达,用SPSS 19.0分析比较miR-630的表达含量.结果:伴OSF口腔癌组织与正常口腔黏膜组织相比,miR-630的表达升高(P＜0.05);伴OSF口腔癌癌旁组织与正常口腔黏膜组织相比,miR-630的表达升高(P＜0.05);伴OSF口腔癌组织与OSF黏膜组织相比,miR-630的表达升高(P＜0.05);伴OSF口腔癌癌旁组织与OSF黏膜组织相比,miR-630的表达有升高(P＜0.05):伴OSF口腔癌组织与伴OSF口腔癌癌旁组织相比,miR-630的表达有升高的趋势,但未见显著统计学差异(P＞ 0.05);OSF黏膜组织与正常口腔黏膜组织相比,miR-630的表达无统计学差异(P＞0.05).结论:miR-630在伴OSF口腔鳞癌组织中表达较正常黏膜组织及OSF组织均显著增加,其异常高表达可能与口腔癌及OSF癌变的发生、发展相关.     

口腔鳞癌端粒酶活性的检测及临床意义

目的　探讨端粒酶活性和口腔鳞癌发生、发展的关系。方法　采用TRAP -PCR -ELISA法对 32例口腔鳞癌标本、1 5例癌旁组织和 1 0例正常口腔粘膜组织进行端粒酶活性检测和分析。结果　口腔鳞癌组织中端粒酶活性值显著高于癌旁组织和正常组织 (P <0 .0 5)。端粒酶在口腔鳞癌标本中阳性检出率 71 .87% ,显著高于癌旁组织和正常组织 (P <0 .0 1 ) ,且和鳞癌的病理分级及有无颈淋巴结转移密切相关。结论　端粒酶活性和口腔鳞癌的发生、发展有密切关系     

HIV感染者口腔念珠菌负荷及生物型研究

目的调查人类免疫缺陷病毒（human immunodeficiency virus，HIV）感染者口腔中念珠菌负荷状况、生物分型及与口腔念珠菌病临床表现的关系。方法采取漱口法对64例HIV感染者和42名健康对照者进行口腔念珠菌的定量分离培养，并综合利用革兰染色、厚壁孢子生成实验、CHROMagar显色培养和API 20C AUX酵母菌鉴定系统对分离株进行生物型鉴定。结果64例HIV感染者中，52例中可分离出念珠菌74株，阳性分离率为81．3％，而42名健康对照者口腔念珠菌阳性分离率仅为16．7％（P〈0．001）。通过对74株念珠菌的生物型进行鉴定，发现有39株白色念珠菌，15株热带念珠菌及其他6个生物型20株。健康对照组中，分离出5株白色念珠菌和其他裂2株。结论HIV感染者口腔念珠菌感染率明显增加，其口腔念珠菌的检出率和负荷量亦明显增加，白色念珠菌和热带念珠菌为其主要分离菌；与健康对照组相比，HIV感染者的口腔念珠菌分离株生物类型旱现多样化。     

Phospholipase activity of Candida albicans isolates from patients with denture stomatitis: the influence of chlorhexidine gluconate on phospholipase production

BACKGROUND AND OBJECTIVES: The extracellular phospholipases of Candida albicans are considered to play a significant role in the pathogenesis of human infections. Therefore 23 clinical oral isolates of C. albicans from patients with denture stomatitis and 22 commensal oral isolates obtained from the palatal mucosa of healthy subjects were assayed for phospholipase activity. It is generally accepted that chlorhexidine gluconate is an appropriate adjunct or an alternative to antimycotic therapy in the management of oral candidiasis. However, the intraoral concentrations of this antiseptic fluctuate considerably due to the dynamics of the oral cavity. So the second main objective of this study was to investigate the effect of brief exposure (30 min) to two sub-therapeutic concentrations (0.002% and 0.0012%) of chlorhexidine gluconate on the value of phospholipase production (Pz) of C. albicans. METHOD: An in vitro phospholipase production was done by plate assay method using an egg yolk-agar medium. RESULTS: No significant differences were found in the number of C. albicans isolates producing phospholipase between two groups. However, the mean value of Pz produced by the isolates from patients with denture stomatitis was significantly (p<0.05) higher than the commensals. Exposure of the isolates to 0.002% and 0.0012% chlorhexidine led to a significant (p<0.001 and p<0.01, respectively) reduction in the amount of phospholipase. CONCLUSION: The results of this study imply that sub-therapeutic levels of chlorhexidine may modulate candidal phospholipase activity, thereby suppressing pathogenicity of C. albicans.     

Oral distribution of Candida species and presence of oral lesions in Brazilian leprosy patients under multidrug therapy

Objective:  The aim of this study was to evaluate the prevalence of Candida spp. and presence of oral lesions in Brazilian leprosy patients under multidrug therapy (MDT).
Methods:  Thirty-eight individuals (18 males and 20 females, median age 53 years) clinically and microbiologically diagnosed as leprosy (lepromatous variant), and under MDT for at least 45 days were studied. The control group constituted by 38 healthy individuals (median age 53.5), matched to the test group in relation to age, gender and oral conditions. Oral rinses were collected and the Candida identification was performed by phenotypic tests. The existence of Candida dubliniensis among the isolates was analyzed using a validated multiplex PCR assay. Twenty-nine leprosy patients were examined intra-orally for the presence of lesions. Data were analyzed by z- and Mann–Whitney tests (α = 5%).
Results:  Yeast carriage rate between leprosy patients (65.8%) and controls (47.4%) was similar ( P  = 0.099), and no significant difference between yeast counts was observed ( P  = 0.1004). Candida albicans was the most frequently isolated species in both groups. In the leprosy group, Candida tropicalis and Candida parapsilosis were also identified. In the control group, we additionally identified Candida tropicalis , Candida glabrata and Candida kefyr. Candida dubliniensis was not detected. No leprosy-related oral lesion was registered.
Conclusion:  Within the limits of the study, we concluded that Brazilian leprosy patients under MDT showed similar levels of carriage and Candida species distribution in relation to the controls.     

Oral epithelium-Candida glabrata interactions in vitro

BACKGROUND: Oropharyngeal candidiasis is a common opportunistic infection and Candida glabrata is the second or third most frequently isolated species from oropharyngeal candidiasis lesions, after Candida albicans. The aim of this study was to study the cytokine-inducing and cell-damaging potential of C. glabrata in oral epithelial cells and compare this to C. albicans. METHODS: Oral epithelial cell lines and primary gingival epithelial cells were cocultured with C. glabrata strains GDH2269 and 94-11 or C. albicans strains SC5314 and ATCC28366. Supernatants were analysed for the presence of interleukin-1alpha (IL-1alpha), IL-8 and granulocyte-macrophage colony-stimulating factor (GM-CSF) by enzyme-linked immunosorbent assay. The cytotoxity of different strains was determined using the CytoTox-96 assay. RESULTS: Compared to C. albicans, C. glabrata induced different proinflammatory cytokine responses in oral epithelial cells; a high level of GM-CSF induction was only detected in C. glabrata-infected cells and not in C. albicans-infected cells, regardless of the origin of these cells (cell lines or primary cells) or the strain used. Like C. albicans, C. glabrata induced an IL-1alpha response by oral epithelial cells, but this response was both strain-dependent and epithelial cell origin-dependent. Unlike C. albicans, C. glabrata failed to induce a strong IL-8 response in any of the cell systems studied. Finally, in these studies C. glabrata showed lower cytotoxicity than C. albicans. CONCLUSIONS: C. glabrata is less cytotoxic than C. albicans and induces different proinflammatory cytokine responses in oral epithelial cells.     

Low virulent oral Candida albicans strains isolated from smokers

It is widely accepted that tabagism is a predisposing factor to oral candidosis and cumulate data suggest that cigarette compounds may increase candidal virulence. To verify if enhanced virulence occurs in Candida albicans from chronic smokers, a cohort of 42 non-smokers and other of 58 smokers (all with excellent oral conditions and without signs of candidosis) were swabbed on tong dorsum and jugal mucosa. Results showed that oral candidal loads do not differ between smoker and non-smokers. Activities of secreted aspartyl-protease (Sap), phospholipase, chondroitinase, esterase-lipase, and haemolysin secretions were screened for thirty-two C. albicans isolates. There were detected significant increments in phospholipasic and chondroitinasic activities in isolates from non-smokers. For other virulence factors, no differences between both cohorts were achieved.     

HIV感染者及艾滋病患者口腔白色念珠菌毒性的体外研究

目的从白色念珠菌本身毒性变化的角度探讨人类免疫缺陷病毒(HIV)感染者易感染口腔念珠菌病的原因。方法通过体外试验从天冬氨酸蛋白酶活性、对颊黏膜上皮细胞的黏附性两方面比较HIV阳性与阴性宿主口腔内白色念珠菌的致病能力。结果在天冬氨酸蛋白酶活性和黏附性方面,HIV阳性口腔念珠菌病致病菌的毒性显著低于HIV阴性口腔念珠菌病致病菌(P<0.01);寄生菌间差异无统计学意义;HIV阳性宿主中,口腔念珠菌病致病菌与寄生菌间差异无统计学意义;而HIV阴性宿主中,口腔念珠菌病致病菌毒性显著高于寄生菌(P<0.01)。结论HIV感染者口腔念珠菌病与某些占主导优势的高毒性菌株无关,而HIV阴性的普通宿主则可能与其选择毒性更强的菌株有关。     

各年龄段儿童口腔中念珠菌的分布研究

目的 研究以白色念珠菌为代表的念珠菌群在不同年龄阶段儿童口腔中的分布情况。方法 对4个不同年龄阶段的儿童口腔中的念珠菌群进行研究，颊黏膜拭子取样，鉴定培养基培养鉴定，比较培养法和PCR法对其中一组样本的白色念珠菌检出率的影响。结果念珠菌的检出率分别是：新生儿7．5％，乳牙列儿童组70％，混合牙列儿童组56．36％，恒牙列儿童组49．12％；白色念珠菌的比例各有不同，PCR方法比培养法更加敏感。结论 各个年龄阶段儿童口腔中均有念珠菌的检出，但检出率不同，白色念珠菌是主要成分。     

Phenotypic and genotypic characterization of oral yeasts from Finland and the United States

A total of 4–22 isolates of oral yeasts per subjects from 48 yeast-positive Finnish and American subjects (25 females and 23 males) were phenotyped and genotyped to determine the frequency of simultaneous oral carriage of multiple yeast taxa. An oral sample from either periodontal pockets, oral mucosa or saliva was obtained. All subjects yielded Candida albicans and 3 subjects an additional yeast species ( Candida krusei, Candida glabrata or Saccharomyces cerevisiae ). The API 20C Aux kit distinguished 9 different carbohydrate assimilation profiles among the C. albicans isolates. Thirty-eight of 46 C. albicans biotype I isolates were categorized in a single numerical profile. PCR analysis, using a random primer OPA-03 and a repetitive primer (GACA)₄, detected 2 major genotypic groups among the C. albicans isolates; 44 subjects showing isolates with a "typical" PCR-profile and 4 subjects isolates with an "atypical" PCR-profile. The "atypical" PCR-profile was similar to that of Candida dubliniensis. All C. albicans isolates assimilated xylose, except 5, including the 4 with an "atypical" PCR-profile. No difference was found in distribution of oral yeast species, and of C. albicans phenotypes and genotypes between Finnish and American subjects. The present PCR method may offer a rapid and easy means of distinguishing oral Candida species.