口腔白念珠菌基因型分析及临床意义

目的 研究不同口腔黏膜病白念珠菌分离株的基因型特点。方法 采用计算机系统辅助随机扩增多态性DNA(RAPD)分析，对健康人和黏膜病患者口腔的38株念珠菌菌株进行基因分型。结果 38株菌株中36株被鉴定为白念菌，其余2株为热带念珠菌。白念菌RAPD分析共出现21种RAPD带型。扁平苔藓组与口腔念珠菌病组间白念致病菌RAPD指纹图无明显相似性。结论 不同基因型白念菌的定植可能与口腔黏膜病的种类有关。     

口腔黏膜病患者口腔念珠菌感染情况的分析

目的 分析了解口腔黏膜病患者感染白念珠菌的情况。方法 收集2019年就诊于口腔黏膜科并进行白念珠菌培养的2 289 例患者,收集其基本信息、临床资料及实验室检查情况。按年龄分组:0～16岁(1组,38例),17～29岁(2组,181例),30～39岁(3组,274例),40～49岁(4组,325例),50～59岁(5组,535例),60～69岁(6组,540例),70岁及以上(7组,396例)。结果 白念珠菌总感染率为 30.6%,且女性患者感染率高于男性(33.1% vs.25.1%,P<0.05)。随着年龄的增长,白念珠菌感染率总体是上升的,且第6、7组感染率明显高于第2、3、4、5组(P<0.05)。除了口腔念珠菌病本身,唇舌疾病及口腔斑纹类疾病中最容易检测出白念珠菌,且白念珠菌的阳性检出与唇舌疾病、干燥综合征、口腔斑纹类疾病等相关。在同时进行白念珠菌培养及真菌镜检且白念珠菌培养阳性的患者中,真菌镜检阳性为50例,阳性率为35.5%。对白念珠菌培养阳性患者进行制霉素片及2%～3%碳酸氢钠溶液的局部治疗,其药物有效率为81.36%。结论 口腔念珠菌病更容易发生于60岁以上老年女性;且与系统性疾病、口腔斑纹类疾病相关。制霉素片联合2%～3%碳酸氢钠溶液局部治疗口腔念珠菌病效果尚可。     

小鼠对口腔念珠菌感染的体液免疫应答

目的建立敏感株和阻抗株小鼠口腔念珠菌感染模型，揭示两种小鼠对口腔念珠菌感染的体液免疫反应。方法雌性BALB／c和CBA／CaH小鼠及白色念珠菌3630用于本研究。1×10^8念珠菌／20μl接种于小鼠的口腔黏膜，建立口腔念珠菌感染模型；SDS—PAGE和Western—Blotting用于检测血清抗体。结果念珠菌敏感株鼠CBA／CaH的口腔感染比阻抗株鼠BALB／c严重（P〈0．05）；CBA／CaH小鼠在口腔免疫后5周产生了IgG1、IgG2a、IgM，而BALB／c小鼠仅产生IgG1。结论念珠菌敏感鼠CBA／CaH的口腔念珠菌感染比念珠菌阻抗鼠BALB／c感染更为严重；抗白色念珠菌抗体IgM可能对宿主的口腔念珠菌感染起保护作用。     

口腔白念珠菌基因分型研究进展

本文对白念菌基因分型方法及基因分型在口腔粘膜病领域中的应用作一综述，指出基因分型是白念珠菌流行病学研究的主要方法。     

艾滋病伴发口腔白色念珠菌感染1例

临床病例资料 患者,女,38岁。因舌部白色斑块7个月来我院口腔内科就诊。6^＋月前,患者曾就诊于当地医院,给予抗炎治疗（具体不详）半年,未见好转,故来我院就诊。既往体健,1年前离异,否认有输血史、吸毒史和冶游史,无肝炎、结核病史。     

复发性口腔念珠菌病患者感染源初探

目的:分析复发性口腔念珠菌病患者感染菌株的同源性,初步探讨同一病人感染反复发作是否缘于复发或再感染。方法:对4例复发性口腔念珠菌病患者口腔的10株念珠菌菌株(P1:004、022;P2:011、020、027、029;P3:007、016;P4:023、024)进行分离纯化鉴定,采用计算机系统辅助随机扩增多态性DNA(random amplifiedpolymorphic DNA,RAPD)分析,获得10株菌株的RAPD指纹图,比较菌株的同源性。结果:10株菌株中9株被鉴定为白念珠菌,1株(023)为热带念珠菌。分离自P1和P3的白念珠菌的RAPD基因型相同;P2的020、027、029号菌株基因型相同,而011号菌株不相同;P4的2株菌株不同种。结论:复发性口腔念珠菌病可能存在两方面病因:继往感染复发和/或再感染新菌株。     

纸片汉检测白念珠菌的临床应用及评价

应用选择性培养基与化学指示剂吸附于混合纤维素酯微孔滤膜所制成的圆片，对５０例口珠菌病可疑患者进行检测，其检出率与常规培养的差异无显著性（Ｐ＞０．０５）。该圆片操作简便、价格低廉，并能在２４小时内取得结果，因此可简易快速的白念珠菌检测手段，供临床推广应用。     

口腔黏膜病临床治疗Ⅴ.口腔念珠菌病诊断与治疗进展

口腔念珠菌病（oral eandidiasis）是念珠菌属真菌引起的口腔黏膜感染性疾病。近年来，由于抗生素和免疫抑制剂在临床上的广泛使用，发生菌群失调或免疫力降低，导致内脏、皮肤、黏膜被真菌感染的病例日益增多，口腔念珠菌病的发病率也相应增高。     

白念珠菌的转变方式及其在口腔念珠菌病中的致病作用

一般认为白念珠是单一的生物体，只具有简单的发育能力，即形成芽孢和菌丝的能力，最近发现这种机会性致病原可发生菌落形态与色泽的转变（switching)，而且其生理性状和发育能力也随之改变，本文就白念珠菌的两种转变方式及其在口腔念珠菌病中的作用作一简要综述。     

口腔白念珠菌分子流行病学研究进展

本文从真菌学的角度对口腔白念珠菌菌种分类、地域分布差异、复发感染的传染源、耐药性机制传播途径等方面进行综述。     

Gene targeting demonstrates that inducible nitric oxide synthase is not essential for resistance to oral candidiasis in mice, or for killing of Candida albicans by macrophages in vitro

Introduction:  Oral candidiasis is caused by opportunistic infections with the yeast Candida albicans . Previous studies have demonstrated important roles for innate immunity and T helper type 1-mediated inflammatory reactions in recovery from infection, with macrophages and neutrophils as key effector cells. Both effector cell types use the inducible isoform of nitric oxide synthase (iNOS) to generate candidacidal molecules, but it is not clear whether nitric oxide (NO) is an absolute requirement for candidacidal effector activity.
Methods:  In this study we directly investigated the role of iNOS-derived NO in resistance to murine experimental oral candidiasis, using iNOS knockout mice.
Results:  Knockout mice were no more susceptible to oral candidiasis than wild-type controls. Bone marrow-derived macrophages from the knockout mice killed C. albicans yeasts efficiently in vitro , and were still able to produce nitrites in an iNOS-independent manner, albeit less efficiently than wild-type controls. There were no significant differences in local mucosal production of interleukins 6, 12, 17A, or 23, interferon-γ, or transforming growth factor-β 24 h after oral challenge with C. albicans .
Conclusion:  These data suggest that iNOS-derived NO is not required for resistance to oral candidiasis in vivo , and that bone marrow-derived macrophages may have iNOS-independent means of generating reactive nitrogen species.     

Irradiation-induced oral candidiasis in an experimental murine model

The aim of this experiment was to establish a mouse model of irradiation-induced oral candidiasis and to explore the cellular populations and mechanisms by which the infection is cleared from the oral mucosa. BALB/c mice received irradiation to the head and neck equivalent to 800 Rad using a Cobalt 60 gamma source. Both irradiated and non-irradiated mice were infected orally with 1 x 10(8) Candida albicans yeasts. Compared with untreated controls, irradiated animals developed a more severe infection of longer duration, with hyphae penetrating the oral mucosa. Monoclonal antibody depletion of CD4+ but not CD8+ T cells from the systemic circulation prolonged the infection in irradiated mice, but not in controls. Supernatants of submandibular and superficial cervical lymph node cultures from irradiated animals demonstrated significantly higher titers of interleukin-12, but similar levels of interferon-gamma compared with controls. Screening for cytokine production by an RNase protection assay detected only macrophage migration inhibition factor in irradiated and non-irradiated oral tissues from day 8 onwards. The results of this study demonstrate a requirement for CD4+ T cells in the recovery from oral candidiasis induced by head and neck irradiation in mice, and are consistent with a role for Th1-type cytokines in host resistance.     

Asymptomatic oral Candida albicans carriage in HIV-infection: frequency and predisposing factors

Many studies have focused on the epidemiology and pathogenesis of oral candidiasis in HIV infection. Little is known on the incidence and predisposing factors of asymptomatic oral Candida carriage in this setting, obviously an important issue in view of prophylaxis. To address this question. 261 consecutive HIV-infected individuals without clinical evidence of candidiasis were investigated. C. albicans was isolated from cultured oral cavity swabs of 63 subjects (24%). Colonization was significantly more frequent in IV drug users. CDC groups IV. and in subjects with lymphocytopenia. CD4+ cell depletion, or elevated beta-2 microglobulin. These data further suggest that oral candidiasis occurs in HIV infection as a result of C. albicans overgrowth and raise the question of primary antifungal prophylaxis in subjects with low CD4 counts and asymptomatic oral Candida carriage.     

Early activation of the interleukin-23-17 axis in a murine model of oropharyngeal candidiasis

Candida albicans is an oral commensal yeast that causes oropharyngeal candidiasis (OPC) in immunocompromised individuals. The immunological pathways involved in OPC have been revisited after the interleukin-17 (IL-17) pathway was implicated in fungal immunity. We studied immediate (<24 h) and adaptive (3-6 day) IL-12 and IL-23-17 pathway activation in naive p40(-/-) mice, which lack IL-12 and IL-23 and develop severe, chronic OPC upon oral inoculation with C. albicans. Macrophages from p40(-/-) mice were less efficient than C57BL/6J controls at killing C. albicans in vitro but very low numbers in the oral mucosae of infected C57BL/6J mice suggest that they are not critical in vivo, at least in this strain. Migration of macrophages to regional lymph nodes of infected p40(-/-) mice was impaired; however, dendritic cell migration was not affected. Recombinant IL-12 therapy provided only temporary relief from OPC, suggesting that IL-23 is required for full protection. In C57BL/6J mice, but not p40(-/-) mice, messenger RNAs encoding IL-23p19 and IL-17 were induced in the oral mucosa within 24 h of infection (6 ± 0.6 and 12 ± 2.7-fold). By day 6 of infection in C57BL/6J mice, IL-17A messenger RNA level had increased 5.1 ± 1.8 and 83 ± 21-fold in regional lymph nodes and oral tissues respectively. Ablation of p40 was associated with delayed or abrogated induction of IL-17A pathway targets (monocyte chemoattractant protein-1, IL-6 and macrophage inflammatory protein-2), and a lack of organized recruitment of neutrophils to the infected oral mucosa. Overall our data show that the IL-23-17A axis is activated early in the oral mucosae of immunologically naive mice with OPC.     

High levels of oral yeasts in early HIV-1 infection

Ten human immunodeficiency virus-1 (HIV-1) infected homosexual or bisexual individuals (ages 24-45) with no history of opportunistic infection were examined, by culture, for the presence of yeasts in whole saliva and on oral mucosa. All were HIV-1 antibody-positive men, non-smokers, non-denture wearers, and taking no medication. The mean salivary level of yeast was four logs higher in the HIV-1 infected group compared to a control group of normal, unmedicated, non-smoking men (ages 20-41) who denied any risk behavior for HIV-1 infection. Identification of the yeast in these HIV-1 positive individuals established that Candida albicans was the predominant species found in whole saliva and on buccal mucosa and tongue. Distinct hyphae were observed with only one mucosal sample. No significant correlation was found between whole saliva yeast concentration and the T4/T8 lymphocyte ratios or absolute number of T4 cells. No correlation was observed between oral yeast concentration and anti-C. albicans IgA titers. The high level of oral yeast in these individuals prior to the development of opportunistic infections is consistent with the suggestion that oral defense mechanisms are compromised in individuals following HIV-1 infection.     

Irradiation‐induced oral candidiasis in an experimental murine model

The aim of this experiment was to establish a mouse model of irradiation‐induced oral candidiasis and to explore the cellular populations and mechanisms by which the infection is cleared from the oral mucosa. BALB/c mice received irradiation to the head and neck equivalent to 800 Rad using a Cobalt 60 gamma source. Both irradiated and non‐irradiated mice were infected orally with 1×10⁸Candida albicans yeasts. Compared with untreated controls, irradiated animals developed a more severe infection of longer duration, with hyphae penetrating the oral mucosa. Monoclonal antibody depletion of CD4⁺ but not CD8⁺ T cells from the systemic circulation prolonged the infection in irradiated mice, but not in controls. Supernatants of submandibular and superficial cervical lymph node cultures from irradiated animals demonstrated significantly higher titers of interleukin‐12, but similar levels of interferon‐γ compared with controls. Screening for cytokine production by an RNase protection assay detected only macrophage migration inhibition factor in irradiated and non‐irradiated oral tissues from day 8 onwards. The results of this study demonstrate a requirement for CD4⁺ T cells in the recovery from oral candidiasis induced by head and neck irradiation in mice, and are consistent with a role for Th₁‐type cytokines in host resistance.     

Pseudomembranous oral candidiasis in HIV infection: Ultrastructural findings

A light and electron microscopic investigation of pseudomembranous candidiasis in HIV infection was undertaken as there is little data available on the ultrastructural features of the invasive phase of Candida in this disease. On examination of biopsy specimens of four patients, histopathology revealed the classic features of superficial candidiasis, including hyphal penetration down to the spinous cell layer, parakeratosis, acanthosis and spongiosis of the infected, superficial epithelium. However, in one case, hyphae traversed the entire epithelium and crossed the basal membrane, invading the adjacent connective tissue. Ultrastructural investigations revealed initial hyphal penetration through the intercellular spaces, possibly demonstrating thigmotropism. However, hyphal penetration was not solely confined to intercellular spaces, as some specimens demonstrated hyphal elements traversing both the cytoplasm and the nuclei of the spinous cells. In these areas of the epithelium appressoria-like appendages were often found at the hyphal tip. These phenomena, commonly described in plant fungi, have rarely been described in human material. Pools of desmosomes were seen in the vicinity of the hyphal pathways, implying that the penetration procedure is associated with detachment and congregation of desmosomes, possibly by enzymatic means. Interestingly, the host immune response to fungal invasion appeared to be minimal, as no immune-effector cells were seen closely associated with either the blastospores or the hyphae in any of the tissues examined. Whether the foregoing events are exaggerated by the abortive immune response seen in HIV-infected patients, or common in immunocompetent individuals during candidal invasion of epithelia, needs to be ascertained by further studies.     

Close association between oral Candida species and oral mucosal disorders in patients with xerostomia

Oral Diseases (2012) 18, 667-672 Objective: Heightened interest in oral health has lead to an increase in patients complaining of xerostomia, which is associated with various oral mucosal disorders. In this study, we investigated the relationship between Candida species and oral mucosal disorders in patients with xerostomia. Subjects and Methods: We evaluated whole salivary flow rate and presence of oral mucosal disorders in 48 patients with xerostomia and 15 healthy controls. The number of Candida species was measured as colony-forming units after propagation on selective medium. Identification of Candida at the species level was carried out by polymerase chain reaction and restriction fragment length polymorphism analysis. We then examined the relationship between Candida species and oral mucosal symptoms. Results: Compared with controls, patients with xerostomia exhibited significantly decreased whole salivary flow rate, increased rate of oral mucosal symptoms, and higher numbers of Candida. Salivary flow rate negatively correlated with the number Candida. Among patients with oral candidiasis, Candida albicanswas isolated from the tongue mucosa and Candida glabratawas isolated from the angle of the mouth. Conclusion: These results suggest that particular Candida species are involved in the pathogenesis of oral mucosal disorders in patients with xerostomia.     

Evaluation of a simplified diagnostic aid (Oricult-N) for detection of oral candidoses

The validity of a simplified diagnostic aid, Oricult-N, for detection of oral candidoses was compared with smears stained according to the periodic acid-SchilFs method. Samples were taken from 80 locations in 36 patients with lesions suspected for candidal infection. There was a statistically significant correlation between the two methods (P < 0.001).