老年住院患者口咽部念珠菌定植状况及菌种分布调查

目的调查老年住院患者口咽部念珠菌定植状况及菌种分布特点,为有效预防念珠菌感染提供参考。方法对解放军第44医院收治的894例住院患者口咽部念珠菌定植状态进行调查分析。结果894例住院患者口咽部标本共培养出念珠菌121株,念珠菌定植率为13．5％,老年患者的定植率高于非老年患者。念珠菌定植以白色念珠菌所占比例最大,占74．5％。年龄≥80岁、肺部基础疾病的存在及使用抗菌药物患者口咽部念珠菌定植率高于普通患者,两者比较差异有统计学意义（P〈0．05）。结论老年患者口咽部念珠菌定植率较高,菌种分布以白色念珠菌最为常见。念珠菌定植与患者年龄、肺部基础疾病的存在及抗菌药物使用情况密切相关。     

Adherence and biofilm formation of non-Candida albicans Candida species

Most cases of candidosis have been attributed to Candida albicans, but recently non-C. albicans Candida species have been identified as frequent human pathogens. Candida pathogenicity has been attributed to several factors, including adhesion to medical devices and/or host cells, biofilm formation, and secretion of hydrolytic enzymes (proteases, phospholipases and haemolysins). Although 'new'Candida species are emerging, there is still a lack of information about their pathogenicity. This review discusses recent advances in our knowledge of Candida glabrata, Candida parapsilosis and Candida tropicalis virulence factors, specifically those of adhesion and biofilm formation, which are key components in Candida pathogenicity.     

Phenotypic and genotypic identification of Candida spp. isolated from hospitalized patients

As candidosis incidence continue to rise, quick laboratory identification of Candida species is becoming increasingly important for a growing population of patients at-risk. RAPD techniques were used on samples of Candida obtained from patients hospitalized at Santa Casa de Misericordia in Belo Horizonte (SCMBH) Brazil, from March 1998 to December 2000 and then compared with the results of phenotypic identification techniques. Two hundred and forty two yeasts were isolated and phenotypically identified as follows: Candida albicans (105), Candida tropicalis (62), Candida parapsilosis (28), Candida glabrata (19), Candida krusei (8), Candida guilliermondii (5) and Candida spp. (15). Samples from the three most frequent species isolated were selected randomly in order to compare the phenotypic and genotypic analyses. Genotypic analysis using RAPD primer M13 (F/R) displayed the best results of all test samples. There was both agreement and consistency between phenotypic and genotypic analysis using RAPD, demonstrating that is possible to apply this method for the identification of Candida species.     

Evaluation of a new chromogenic medium (Candida ID) for the isolation and presumptive identification of Candida albicans and other medically important yeasts

Candidiasis is a frequent human infection caused mainly by Candida albicans. However, other species are emerging as important pathogens, as Candida glabrata, Candida parapsilosis, Candida tropicalis, Candida krusei or Candida guilliermondii. Rapid identification of clinical isolates could facilitate diagnosis and treatment. Candida ID (bioMerieux, Spain) is a new medium for the isolation and presumptive identification of yeasts: C. albicans grows as blue colonies, and C. tropicalis, C. guilliermondii, Candida kefyr and Candida lusitaniae as pink ones. The utility of Candida ID was evaluated with more than 700 clinical isolates and type culture collection strains from different genera including Candida, Cryptococcus, Saccharomyces, and Rhodotorula. Presumptive identification was confirmed by germ tube test, microscopic morphology and chlamydoconidia production on corn meal agar and carbohydrate assimilation on API-ATB ID 32C or Vitek (bioMerieux). Growth on Candida ID was rapid (18-24 h) for most of the yeast strains tested. Sensitivity and specificity of identification of C. albicans was significantly high (>98%), since a very low number of isolates were found to be false negative or false positive. A better result was obtained for species growing as pink colonies (>99.5%). Detection of different species of medical important yeasts was easy with Candida ID, as perfectly distinct colors and textures of colonies were observed on this medium. Candida ID allowed the discrimination between C. glabrata (creamy and smooth) and C. krusei (rough and white) colonies. Other species showed different colony textures and colours, white being the predominant colour. Candida ID was very useful for the presumptive identification C. albicans isolates.     

Comparison of a randomly amplified polymorphic DNA (RAPD) analysis and ATB ID 32C system for identification of clinical isolates of different Candida species

The objective of this work was to compare the usefulness of a randomly amplified polymorphic DNA (RAPD) assay to that of the ATB ID32C kit (bioMérieux, France) for identification of different species of Candida isolated from clinical specimens. The RAPD-PCR patterns obtained with OPE-18 primer for identification of clinical isolates were consistent, and the different independent assays revealed reproduction of the band patterns. RAPD with the OPE-18 primer is a very specific and sensitive method for identification of Candida glabrata, Candida guilliermondii, Candida tropicalis, Candida pelliculosa, Candida albicans, Candida krusei, and Candida lusitaniae.     

Nature of the restructuring of the T- and B-immunity systems in patients with cutaneous and visceral candidiasis

The examination of 90 patients with superficial and visceral candidiasis, as well as Candida carriers, has revealed that the heavy contamination of the body with fungi of the genus Candida is accompanied by the specific transformation of the immune system, manifested by differences in the character of sensitization to Candida antigens: in the patients with superficial and visceral candidiasis the B-system of immunity is sensitized to a greater degree, while in the Candida carriers the sensitization of the T-system is more pronounced. Despite the fact that the immune system of patients with the disseminated form of visceral candidiasis is capable of developing the delayed hypersensitivity (DH) reaction to bacterial allergens, such patients have been shown to develop DH to Candida antigens only in rare cases. This is probably due to disturbances in their immunocompetent systems, caused, seemingly, by the secondary immune insufficiency.     

Yeasts isolated from plant-associated beetles and other insects: seven novel Candida species near Candida albicans

Yeasts related to Candida albicans were isolated from the digestive tracts of beetles in eight families and various orders of insects such as earwigs, crickets, and roaches, most of which were caught at light traps or in a few cases directly from plant materials. Based on comparisons of DNA sequences and other taxonomic characteristics, a total of 41 isolates were identified as Candida orthopsilosis, Candida pseudorhagii, Candida maltosa, Candida parapsilosis, Candida tropicalis, Candida neerlandica, Lodderomyces elongisporus, and seven new Candida species. The new species and type strains are designated as Candida gigantensis NRRL Y-27736T, Candida bohiensis NRRL Y-27737T, Candida alai NRRL Y-27739T, Candida buenavistaensis NRRL Y-27734T, Candida frijolesensis NRRL Y-48060T, Candida labiduridarum NRRL Y-27940T, and Candida tetrigidarum NRRL Y-48142T. A phylogeny based on SSU and LSU rRNA gene sequences indicated that most of the new species were closely related to members of the C. albicans/L. elongisporus clade, such as C. albicans, Candida dulbliniensis, C. neerlandica, Candida chauliodes, and Candida corydali. Candida alai was placed near this clade, but no closely related sister taxon was identified. The ecology of the insect-associated yeasts is discussed and compared with the results from other studies.     

血培养分离出212株念珠菌的菌种分布及耐药性分析

目的分析血培养分离出的念珠菌的菌种分布及耐药分析,为临床念珠菌血症的诊治提供理论依据。方法回顾性分析2017年1月—2020年12月期间,本院血培养分离出的念珠菌的菌种分布、药敏试验结果及患者血培养分离出念珠菌前后96 h内的G试验结果。结果血培养中分离出念珠菌314例,阳性率2.1%,其中非重复分离株212例。检出率最高的是近平滑念珠菌(72株,34.0%),其次是白念珠菌(55株,25.9%)和光滑念珠菌(28株,13.2%)。念珠菌检出率最高的科室为ICU(62株,29.2%),其次是新生儿科(39株,18.4%)和血液科(20株,9.4%)。检出的212株念珠菌除一株近平滑念珠菌为两性霉素B的非野生株,其余均为两性霉素B的野生株。白念珠菌对唑类药物的敏感率超过90%。但光滑念珠菌和热带念珠菌对唑类药物的敏感性较低。血培养分离出念珠菌的前后96 h内,G试验的阳性率为73.7%。结论本院念珠菌检出率前3位分别是近平滑念珠菌、白念珠菌和光滑念珠菌。光滑念珠菌、热带念珠菌对唑类药物敏感性比较低,在经验用药时需要合理选择抗真菌药物。G试验对念珠菌血症有较高的价值,需要对结果进行动态监测。     

Identification and antifungal susceptibility of Candida isolated from intensive care unit patients

Candida was isolated in 205 of 1060 clinical specimens (19.33%) in our laboratary sent from the intensive care unit for mycological investigation between January 98-December 99. All isolated strains were identified to species level using the API Candida system (Bio-Meieux, France) as follows; Candida albicans (n:115, 56.09%), Candida tropicalis (n:23, 11.21%), Candida parapsilosis (n:21, 10.24%), Candida glabrata (n:12, 5.83%). Candida kefyr (n:9, 4.39%), Candida lusitaniae (n:7, 3.41%), Candida famata (n:6, 2.92%), Candida krusei (n:6, 2.92%), Candida guilliermondii (n:6, 2.92%). These stains were identified using congo-red-glucose-brain-heart-infusion agar and slime production was determined in Candida albicans 53.91% and 67.77% in other than Candida species. In the present study, E test (AB Biodisk, Solna, Sweeden) was used to test antifungal susceptibility. The resistance to amphotericin B was 19.51%, to fluconazole 27.31% and to flucytosine 20.00%.     

Saliva promotes survival and even proliferation of Candida species in tap water

Candida yeasts colonize the human oral cavity as commensals or opportunistic pathogens. They may be isolated from water circulating in dental unit waterlines mixed with traces of saliva mainly because of the dysfunction of antiretraction valves. This study deals with the growth ability of Candida albicans, Candida glabrata and Candida parapsilosis in tap water with saliva (0-20% v/v). Results show that C. glabrata is the most susceptible species in tap water. Furthermore, saliva promotes both survival and proliferation of the three studied Candida species in tap water.     

Synthesis and anticandidal activity of some imidazopyridine derivatives

New hydrazide derivatives of imidazo[1,2-a]pyridine have been synthesized and evaluated for anticandidal activity. The reaction of imidazo[1,2-a]pyridine-2-carboxylic acid hydrazides with various benzaldehydes gave N-(benzylidene)imidazo[ 1,2-a]pyridine-2-carboxylic acid hydrazide derivatives. Their anticandidal activities against Candida albicans and Candida glabrata (isolates obtained from Osmangazi University, Faculty of Medicine, Eskisehir, Turkey), Candida albicans (ATCC 90028), Candida utilis (NRLL Y-900), Candida tropicalis (NRLL Y-12968), Candida krusei (NRLL Y-7179), Candida zeylanoides (NRLL Y-1774), and Candida parapsilosis (NRLL Y-12696) were investigated.     

Mechanisms of host defense against Candida species. I. Phagocytosis by monocytes and monocyte-derived macrophages

We studied the biochemical basis of phagocytosis of Candida albicans, a serious pathogen, and Candida parapsilosis, which is rarely pathogenic, by human monocytes (Mo) and monocyte-derived macrophages (MDM). Optimal phagocytosis of both species by Mo required the presence of extracellular Ca2+ and opsonization through both the classic and alternative complement pathways. Serum-opsonized Candida were ingested equally by Mo and MDM; unopsonized Candida were phagocytosed only by macrophages, and uptake began slowly. This opsonin-independent phagocytosis required Ca2+ and could be blocked by yeast mannan or mannose-BSA conjugate, suggesting a role for the mannose receptor. Opsonized Candida elicited a vigorous increase in the concentration of [Ca2+]i in Mo and MDM, but no Ca2+ transient was detected in MDM stimulated with unopsonized Candida. Pretreatment of MDM with ionomycin to increase [Ca2+]i had no effect on phagocytosis of unopsonized Candida. Addition of 5 mM EGTA completely inhibited changes in [Ca2+]i in Mo and MDM, suggesting that the Ca2+ transient induced by opsonized Candida is due to an influx of extracellular Ca2+. Differences in pathogenicity between the two Candida species could not be explained by differences in any aspect of phagocytosis. Uptake mediated by the macrophage mannose receptor could play a role in clearance of Candida under opsonin-poor conditions.     

Probiotic bacteria for prophylaxis and therapy of candidiasis

A good deal of data support a role for probiotic intestinal bacteria in the prophylaxis and therapy of candidiasis. Candida spp. are highly infectious eukaryotes that can colonize and infect humans and other warm-blooded mammals, worldwide. Although most humans manifest antibody- and cell-mediated immune responses to Candida antigens a large percentage of the human population is colonized with Candida spp. in their alimentary and vaginal tracts. The bacterial flora plays a very important probiotic role in the prophylaxis of candidiasis by suppressing the growth of Candida spp. on mucosal and cutaneous surfaces; however, the specific bacteria and the mechanisms they use to inhibit Candida spp. and candidiasis are still poorly understood. The increased incidence of Candida infections, their increasing resistance to antifungal antibiotics and the fact that vaccines to protect against candidiasis are not yet available (and may not work in immunodeficient, Candida-susceptible, patients) provides a strong impetus for new research efforts to explore the use of probiotic, anti- Candida intestinal bacteria for the prophylaxis and therapy of candidiasis.     

Inflammation and gastrointestinal Candida colonization

Candida organisms commonly colonize the human gastrointestinal tract as a component of the resident microbiota. Their presence is generally benign. Recent studies, however, show that high level Candida colonization is associated with several diseases of the gastrointestinal tract. Further, results from animal models argue that Candida colonization delays healing of inflammatory lesions and that inflammation promotes colonization. These effects may create a vicious cycle in which low-level inflammation promotes fungal colonization and fungal colonization promotes further inflammation. Both inflammatory bowel disease and gastrointestinal Candida colonization are associated with elevated levels of the pro-inflammatory cytokine IL-17. Therefore, effects on IL-17 levels may underlie the ability of Candida colonization to enhance inflammation. Because Candida is a frequent colonizer, these effects have the potential to impact many people.     

Ammonium assimilation by Candida albicans and other yeasts: evidence for activity of glutamate synthase

Activities and properties of the ammonium assimilation enzymes NADP+-dependent glutamate dehydrogenase (GDH), glutamate synthase (GOGAT) and glutamine synthetase (GS) were determined in batch and continuous cultures of Candida albicans. NADP+-dependent GDH activity showed allosteric kinetics, with an S0.5 for 2-oxoglutarate of 7.5 mM and an apparent Km for ammonium of 5.0 mM. GOGAT activity was affected by the buffer used for extraction and assay, but in phosphate buffer, kinetics were hyperbolic, yielding Km values for glutamine of 750 microM and for 2-oxoglutarate of 65 microM. The enzymes GOGAT and NADP+-dependent GDH were also assayed in batch cultures of Saccharomyces cerevisiae and three other pathogenic Candida spp.: Candida tropicalis, Candida pseudotropicalis and Candida parapsilosis. Evidence is presented that GS/GOGAT is a major pathway for ammonium assimilation in Candida albicans and that this pathway is also significant in other Candida species.     

白假丝酵母菌耐药与抗氰呼吸的相关性研究

目的探讨白假丝酵母菌的耐药情况及其与抗氰呼吸的相关性。方法用真菌药敏测定试剂盒测定从临床分离出来的37株白假丝酵母菌的耐药性,并从中选出5株耐药菌和5株敏感菌进行抗氰呼吸的研究。结果白假丝酵母菌对益康唑的耐药率最高,达54.1%,耐药白假丝酵母菌的抗氰呼吸速率均值为(17.56±6.75)nmol/(min.A620),敏感白假丝酵母菌的抗氰呼吸速率均值为(7.99±5.80)nmol/(min.A620),耐药白假丝酵母菌的抗氰呼吸速率明显升高,且耐药菌株抗氰呼吸速率占总呼吸的比例明显高于敏感菌株(P0.05),差异具有显著性。结论兰州市区白假丝酵母菌对益康唑耐药性较高,且白假丝酵母菌的耐药与抗氰呼吸途径相关。     

Ozone Treatment Unveils the Veil of Candida parapsilosis Infection in the Knee Joint: A Case Report and Literature Review

Mycopathologia - Candida infection is common, while Candida parapsilosis infection in the knee joint is rare. Local symptoms of Candida infections in the knee are atypical, rarely associated with...     

女性阴道感染的常见病原菌分布情况 及与乳杆菌密度的关系

目的研究女性阴道感染常见病原菌分布情况及与乳杆菌密度的关系。方法选取2016年12月至2018年12月在我院就诊的120例女性生殖系统感染患者作为观察组,另选我院进行健康体检的女性120例作为对照组。分析观察组患者生殖系统感染念珠菌的构成以及耐药情况,探讨两组患者乳杆菌密度差异以及念珠菌、耐药情况与Nugent评分的相关性。结果观察组患者感染主要为白色念球菌,其次为克柔念珠菌、光滑念珠菌、近平滑念珠菌、热带念珠菌、平滑念珠菌和其他念珠菌。观察组患者耐药最高的为咪康唑,其次为酮康唑、伊曲霉素、克霉素、氟康唑、制菌霉素和两性霉素B;观察组患者的Nugent评分显著高于对照组,耐药患者的Nugent评分显著高于非耐药患者;患者念珠菌感染以及耐药情况分别与Nugent评分呈正相关,差异存在统计学意义(均P0.05)。结论患者生殖道乳杆菌密度、白色念珠菌感染情况以及耐药情况分别与Nugent评分呈正相关,在患者的治疗过程当中,可以将乳杆菌数量的恢复情况作为评价其治疗效果的指标之一。     

Identification and susceptibility against fluconazole and albaconazole of 100 yeasts' strains isolated from vaginal discharge

Vulvovaginal candidiasis is a condition that affects a great number of fertile women. It is considered the second cause of genital infection after vaginosis due to GAM complex. Candida albicans is the most frequent isolated species from vaginal discharge. However, sometimes more than one yeast species could be found in the same clinical sample that are more resistant to antifungal drugs. Nowadays, it is necessary to identify properly up to species level the isolated microorganism and to determine the antifungal susceptibility profile. One hundred strains obtained from vaginal discharge of 94 patients suffering acute vulvovaginal candidiasis were studied. The identification of the isolates showed: C. albicans 86%, Candida glabrata 6%, Candida inconspicua 3%, Candida krusei 2% and Candida intermedia, Candida holmii and Trichosporon asahii one case each. Minimal inhibitory concentrations (MIC) of all the yeasts against fluconazole and albaconazole were performed. C. glabrata, C. krusei and C. inconspicua were the most resistant against fluconazole, on the other hand albicans was susceptible to this drug. All the isolates presented MIC against albaconazole much lower than fluconazole.     

Preliminary characterization and grouping of Candida species by numerical analysis of protein profiles obtained by polyacrylamide gel electrophoresis

Whole-cell proteins from isolates of five Candida species (Candida albicans, Candida krusei, Candida parapsilosis, Candida tropicalis and Candida guilliermondii) were separated by SDS-PAGE and the profiles obtained were converted into a binary data matrix that produced a cophenetic correlation phenogram. The analysis of the phenogram allowed detection of the cophenetic correlation levels existing among these species.