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1.
Yeasts from the genus Malassezia are members of the normal biota of human skin, and may play a role in dermatopathology. Our previous study of the fungal microbiota from healthy subjects and from patients with psoriasis using clone library analysis revealed the presence of five Malassezia species and four uncharacterized phylotypes. We now compared the Malassezia microbiota from six healthy body locations and two psoriatic lesions, and evaluated its stability over time using multiplex real-time PCR. Samples from each body location were obtained monthly, for 4 months. Dual-labeled probes were designed to recognize four Malassezia sp. and two uncharacterized groups, and a genus-specific probe was also developed. A good correspondence was obtained between real-time PCR data and clone library analyses. Malassezia restricta was the most abundant species in the majority of samples, and high amounts of Malassezia globosa were also detected. The uncharacterized phylotype 1 was usually detected in lower proportions, nevertheless it was present in most samples. The microbiota was host-specific and relatively stable over time. In accordance with our previous observations, no significant dichotomy between samples from healthy skin and from psoriatic lesions was found; the samples clustered according to the subject, rather than health status.  相似文献   

2.
Our previous research showed that lipophilic yeasts, Malassezia species, colonize the skin of patients with atopic dermatitis (AD) at a high frequency. In this study, we found that two basidiomycetous yeasts, Cryptococcus diffluens and C. liquefaciens, colonize the skin significantly more frequently in AD patients than in healthy subjects. Transparent dressings were applied to the skin of 36 AD patients and 30 healthy subjects and then transferred onto Sabouraud dextrose agar. Colonies recovered from the medium were identified by DNA sequence analysis of internal transcribed spacer regions and the D1/D2 26S rRNA gene. C. diffluens and C. liquefaciens were isolated from 42% (15/36) and 33% (12/36) of AD patients and from 20% (6/30) and 20% (6/30) of healthy subjects, respectively. In addition, fungal DNA was extracted directly from the dressings and amplified in a specific nested PCR assay. C. diffluens and C. liquefaciens DNA were detected in dressings from 97% (35/36) and 86% (31/36) of the AD patients and 47% (14/30) and 37% (11/30) of the healthy subjects, respectively. These findings show that Malassezia spp. are not the only yeasts that colonize the skin of AD patients; Cryptococcus spp. also are present in a high proportion of patients. The role of these microorganisms in AD is as yet unknown, but the current findings, in combination with previous results, indicate that C. diffluens, C. liquefaciens, M. globosa, and M. restricta together colonize the skin surface of AD patients at a high frequency.  相似文献   

3.
Rapid non-culture-dependent assays for identification of fungi quicken diagnosis and prompt treatment of invasive fungal disease. Fungal DNA extracts from pure cultures of the most frequently isolated fungal pathogens belonging to the Genera Aspergillus, Candida and Cryptococcus along with less common pathogenic Genera were amplified with the general fungal primer pair internal transcribed spacer-1/4. Subsequently, the amplicon was digested with the restriction endonucleases MspI, HaeIII, HinfI and EcoRI in order to generate genus- or species-specific patterns for identification of the fungus. HinfI produced indistinguishable fingerprints for all Aspergillus species tested. MspI produced species-specific patterns for: Cryptococcus neoformans, Cryptococcus non-neoformans, Candida albicans and Candida tropicalis. EcoRI succeeded in differentiating penicillia from aspergilli and cryptococci from Candida spp. It is concluded that this procedure can differentiate genera and occasionally species of medically important fungi and that following the necessary validation experiments, it can be used directly on clinical samples to assist prompt diagnosis of systemic fungal infections.  相似文献   

4.
Malassezia yeasts are part of the resident cutaneous microbiota, and are also associated with skin diseases such as seborrheic dermatitis (SD). The role these fungi play in skin diseases and why they are pathogenic for only some individuals remain unclear. This study aimed to characterize Malassezia microbiota from different body sites in healthy and SD subjects from Brazil. Scalp and forehead samples from healthy, mild SD and severe SD subjects were collected. Non-scalp lesions from severe SD patients were also sampled. 5.8S rDNA/ITS2 amplicons from Malassezia sp. were analyzed by RFLP and sequencing. Results indicate that Malassezia microbiota did not group according to health condition or body area. Phylogenetic analysis revealed that three groups of sequences did not cluster together with any formally described species, suggesting that they might belong to potential new species. One of them was found in high proportions in scalp samples. A large variety of Malassezia subtypes were detected, indicating intra-specific diversity. Higher M. globosa proportions were found in non-scalp lesions from severe SD subjects compared with other areas, suggesting closer association of this species with SD lesions from areas other than scalp. Our results show the first panorama of Malassezia microbiota in Brazilian subjects using molecular techniques and provide new perspectives for further studies to elucidate the association between Malassezia microbiota and skin diseases.  相似文献   

5.
Differences in the intestinal microbiota between children and adults with celiac disease (CD) have been reported; however, differences between healthy adults and adults with CD have not been clearly demonstrated. The aim of this study was to evaluate the differences in the intestinal microbiota between adults with CD and healthy individuals. Microbial communities in faecal samples were evaluated by PCR-denaturing gradient gel electrophoresis (DGGE) and gas-liquid chromatography of short chain fatty acids (SCFAs). The study group included 10 untreated CD patients, 11 treated CD patients and 11 healthy adults (in normal gluten diet and in GFD). UPGMA clustered the dominant microbial communities of healthy individuals together and separated them from the dominant microbial communities of the untreated CD patients. Most of the dominant microbial communities of the treated CD patients clustered together with those of healthy adults. The treated CD patients showed a reduction in the diversity of Lactobacillus and Bifidobacterium species. The presence of Bifidobacterium bifidum was significantly higher in untreated CD patients than healthy adults. There was a significant difference between untreated CD patients and healthy adults, as well as between treated CD patients and healthy adults, regarding acetic acid, propionic acid, butyric acid, and total SCFAs. In conclusion: healthy adults have a different faecal microbiota from that of untreated CD patients. A portion of the treated CD patients displayed a restored "normal" microbiota. The treated CD patients significantly reduce the Lactobacillus and Bifidobacterium diversity. Healthy adults have a different faecal SCFAs content from that of CD patients.  相似文献   

6.
Gao Z  Tseng CH  Strober BE  Pei Z  Blaser MJ 《PloS one》2008,3(7):e2719
For psoriasis, an idiopathic inflammatory disorder of the skin, the microbial biota has not been defined using cultivation-independent methods. We used broad-range 16S rDNA PCR for archaea and bacteria to examine the microbiota of normal and psoriatic skin. From 6 patients, 19 cutaneous samples (13 from diseased skin and 6 from normal skin) were obtained. Extracted DNA was subjected to the broad range PCR, and 1,925 cloned products were compared with 2,038 products previously reported from healthy persons. Using 98% sequence identity as a species boundary, 1,841 (95.6%) clones were similar to known bacterial 16S rDNA, representing 6 phyla, 86 genera, or 189 species-level operational taxonomic unit (SLOTU); 84 (4.4%) clones with <98% identity probably represented novel species. The most abundant and diverse phylum populating the psoriatic lesions was Firmicutes (46.2%), significantly (P<0.001) overrepresented, compared to the samples from uninvolved skin of the patients (39.0%) and healthy persons (24.4%). In contrast, Actinobacteria, the most prevalent and diverse phylum in normal skin samples from both healthy persons (47.6%) and the patients (47.8%), was significantly (P<0.01) underrepresented in the psoriatic lesion samples (37.3%). Representation of Propionibacterium species were lower in the psoriatic lesions (2.9+/-5.5%) than from normal persons (21.1+/-18.2%; P<0.001), whereas normal skin from the psoriatic patients showed intermediate levels (12.3+/-21.6%). We conclude that psoriasis is associated with substantial alteration in the composition and representation of the cutaneous bacterial biota.  相似文献   

7.
Cryptococcus diffluens and Cryptococcus liquefaciens, 2 basidiomycetous yeasts, frequently colonize the skin of patients with atopic dermatitis (AD). In this study, we investigated the presence of specific IgE antibodies against C. diffluens and C. liquefaciens in the sera of AD patients by using an enzyme immunoassay . Of the 122 AD serum samples tested, 43 (35.2%) and 50 (41.0%) were positive for specific IgE antibodies against C. diffluens and C. liquefaciens, respectively. The levels of specific IgE against the C. diffluens antigen and that against the C. liquefaciens antigen were strongly correlated (r=0.96). In contrast, no remarkable correlation was observed between the levels of specific IgE against the 2 Cryptococcus species and that of specific IgE against Malassezia restricta. Competitive enzyme-linked immunosorbent assay (ELISA) inhibition tests revealed that C. diffluens and C. liquefaciens shared common antigens. This finding was consistent with the IgE immunoblotting data which demonstrated that several IgE-binding proteins with molecular masses of 77, 54, and 30 kDa were recognized in both C. diffluens and C. liquefaciens antigens . These results suggest that fungal components from C. diffluens and C. liquefaciens may act as allergens and play a role in the pathogenesis of AD.  相似文献   

8.
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.  相似文献   

9.
Diabetes mellitus and candidiases   总被引:1,自引:0,他引:1  
Patients in various clinical states of diabetes mellitus (according to the recommendation of the American Diabetes Association) as a primary diagnosis were examined for fungal infections by Candida species. Candida spp. were detected in urine, in the material taken from the mouth cavity, nails, skin lesions, ears and eyes, by cultivation on the Sabouraud agar, CHROMagar Candida, and by saccharide assimilation. In the group of diabetics with symptoms of oral candidiasis and denture stomatitis C. albicans was identified in 8 cases, C. tropicalis in 3, C. parapsilosis in 2; 1 strain of C. guilliermondii was also isolated. In patients with urinary tract infections the presence of C. albicans was shown in 12 cases; C. parapsilosis was detected in 6 cases and two strains of each C. tropicalis and C. krusei were also isolated. In patients with leg ulcers C. albicans (25 cases), C. parapsilosis (5), C. tropicalis (3) and one strain of each C. krusei and C. robusta were isolated. Otomycosis was associated with one strain of C. albicans, C. parapsilosis, C. tropicalis and C. guilliermondii. C. albicans was most frequently associated with onychomycosis, paronychia and endophthalmitis; C. parapsilosis was the second most rated yeast.  相似文献   

10.
The oral microbiome–organisms residing in the oral cavity and their collective genome–are critical components of health and disease. The fungal component of the oral microbiota has not been characterized. In this study, we used a novel multitag pyrosequencing approach to characterize fungi present in the oral cavity of 20 healthy individuals, using the pan-fungal internal transcribed spacer (ITS) primers. Our results revealed the “basal” oral mycobiome profile of the enrolled individuals, and showed that across all the samples studied, the oral cavity contained 74 culturable and 11 non-culturable fungal genera. Among these genera, 39 were present in only one person, 16 genera were present in two participants, and 5 genera were present in three people, while 15 genera (including non-culturable organisms) were present in ≥4 (20%) participants. Candida species were the most frequent (isolated from 75% of participants), followed by Cladosporium (65%), Aureobasidium, Saccharomycetales (50% for both), Aspergillus (35%), Fusarium (30%), and Cryptococcus (20%). Four of these predominant genera are known to be pathogenic in humans. The low-abundance genera may represent environmental fungi present in the oral cavity and could simply be spores inhaled from the air or material ingested with food. Among the culturable genera, 61 were represented by one species each, while 13 genera comprised between 2 and 6 different species; the total number of species identified were 101. The number of species in the oral cavity of each individual ranged between 9 and 23. Principal component (PCO) analysis of the obtained data set followed by sample clustering and UniFrac analysis revealed that White males and Asian males clustered differently from each other, whereas both Asian and White females clustered together. This is the first study that identified the “basal mycobiome” of healthy individuals, and provides the basis for a detailed characterization of the oral mycobiome in health and disease.  相似文献   

11.
The onychomycosis incidence was determined in 250 type 2 diabetes mellitus (T2DM) patients who were registered at the Internal Medicine Service from a Mexico city General Hospital throughout a year (January-December 2006). Out of the total of studied T2DM patients, 93 (37.2%) showed ungual dystrophy and from these, in 75.3% a fungal etiology was corroborated. Out of 70 patients, 34 were men and 36 women, with an average of 63.5 years. Correlation between T2DM evolution time and onychomycosis was significant (P < 0.01). Distal-lateral subungual and total dystrophic onychomycosis were the most frequent clinical types (55.1% and 33.7%, respectively). Fifty-eight fungal isolates were obtained; 48.6% corresponded to dermatophytes, Trichophyton rubrum being the first species (37.1%). All these strains corresponded to two morphological varieties: "yellow" and typical downy. From the yeast-like isolates, 12 corresponded to Candida spp., firstly C. albicans and C. parapsilosis; three to Cryptococcus spp. (C. albidus, C. uniguttulatus and C. laurentii); two Trichosporon asahii; and only one to Pichia ohmeri. Six non-dermatophytic molds were isolated: two Chrysosporium keratinophylus, two Scopulariopsis brevicaulis, one Aspergillus fumigatus, and one Acremonium sp. The fungal mixture corresponded to T. mentagrophytes with C. guilliermondii; T. mentagrophytes with C. glabrata; T. rubrum with C. glabrata; T. rubrum with P. ohmeri.  相似文献   

12.

Background

Psoriasis and atopic dermatitis (AD) are chronic inflammatory skin diseases, which negatively influence the quality of life. In the last years, several evidences highlighted the pivotal role of skin bacteria in worsening the symptomatology of AD and psoriasis. In the present study we evaluated the skin microbiota composition in accurately selected subjects affected by (AD) and psoriasis.

Methods

Three first cousins were chosen for the study according to strict selection of criteria. One subject was affected by moderate AD, one had psoriasis and the last one was included as healthy control. Two lesional skin samples and two non-lesional skin samples (for AD and psoriatic subjects) from an area of 2 cm2 behind the left ear were withdrawn by mean of a curette. For the healthy control, two skin samples from an area of 2 cm2 behind the left ear were withdrawn by mean of a curette. DNA was extracted and sequencing was completed on the Ion Torrent PGM platform. Culturing of Staphylococcus aureus from skin samples was also performed.

Results

The psoriatic subject showed a decrease in Firmicutes abundance and an increase in Proteobacteria abundance. Moreover, an increase in Streptococcaceae, Rhodobacteraceae, Campylobacteraceae and Moraxellaceae has been observed in psoriatic subject, if compared with AD individual and control. Finally, AD individual showed a larger abundance of S. aureus than psoriatic and healthy subjects. Moreover, the microbiota composition of non-lesional skin samples belonging to AD and psoriatic individuals was very similar to the bacterial composition of skin sample belonging to the healthy control.

Conclusion

Significant differences between the skin microbiota of psoriatic individual and healthy and AD subjects were observed.
  相似文献   

13.
刘昊斓  吴云当  阮岩 《菌物学报》2020,39(12):2251-2260
本研究针对广东地区真菌性外耳道炎患者,采集健康对照组以及患病组外耳道分泌物,提取其总DNA,分析其微生物群落结构、多样性变化以及真菌与细菌之间的相关关系。结果显示,对于细菌而言,致病细菌不仅存在于患病组耳道,也存在于健康人群的耳道当中;对于真菌而言,虽然健康组也检出了真菌,但与细菌不同的是,患病组与健康组的真菌群落差异显著。健康组耳道真菌以担子菌门Basidiomycota为主,该类真菌并不是真菌性外耳道炎的致病菌,而在患病组中,子囊菌门Ascomycota的曲霉属Aspergillus占据绝对优势地位。曲霉是重要的致病菌,在10个患病组样本中,8个样本的曲霉属占比超过90%。此外,真菌与细菌之间,仅有极少数菌种的丰度变化存在正相关关系,多数细菌与真菌的丰度变化并不相关,这意味着在耳道环境中,真菌与细菌群落变化的依存关系不明显。总的来说,健康人群与患病人群的耳道环境均存在致病菌,致病菌的存在并不必然导致耳道炎症的发生,菌群变化只是炎症产生的前提。而曲霉在耳道的大量繁殖是真菌性外耳道炎发病的重要原因,维持一种不利于该菌繁殖的耳道环境,可能是预防真菌性外耳道炎发病的有效措施。  相似文献   

14.
The proportion of yeast species involved in eye infections in 11 patients was examined. The presence of yeast organisms as causative agents of endophthalmitis was found in corneal smears (n=4), conjunctival swabs (4), and vitreous fluid (3). Altogether 5 strains ofCandida albicans, 2 strains ofC. krusei and one strain each ofC. guilliermondii, C. parapsilosis, C. tropicalis andCryptococcus neoformans were isolated from the clinical material. The hematogenic origin of endophthalmitis was proved in 7 cases on the basis of positive blood samples and in 2 cases by the isolation of yeasts from the tip of an intravenous catheter. Endophthalmitis-supporting risk factors such as indwelling intravenous catheters, prolonged use of broad-spectrum antibiotics and chemotherapy, surgical intervention, diabetes mellitus, and malignancy were observed in the patients.  相似文献   

15.
In view of the increase in yeast infections, especially polymicrobial ones, differential culture media have acquired increasing importance. The present study evaluated the Sabouraud chloramphenicol, Biggy agar, Pagano Levin agar and CHROMagar Candida media in terms of isolation, number of yeast colony forming units per plate, and inhibition of bacteria and filamentous fungi. To this end, we used 223 biological samples, including feces, and oral, vaginal and anal mucosae from 86 patients presenting or not symptoms of fungal infections. The four media did not differ significantly in terms of detection of yeast-positive cultures. The number of colony forming units per plate ranged from zero to 2.380, with a predominance of counts of 1 to 9 colonies per plate. No significant differences were observed among the four culture media in terms of number of colonies counted, for each kind of biological material. Fifteen species belonging to the genera Candida, Saccharomyces, Cryptococcus, Trichosporon and Rhodotorula were isolated, with C. albicans being the predominant species, followed by C. parapsilosis and R. rubra. CHROMagar Candida and Biggy agar were complementary in the isolation of the different species and favored a greater recovery of polymicrobial cultures. Pagano Levin agar isolated the smallest variety of species. Sabouraud chloramphenicol agar was the least effective in terms of bacterial inhibition and favored a greater development of filamentous fungi. The results suggest that more than one culture medium should be used for an adequate primary isolation.  相似文献   

16.
An in vitro susceptibility testing of 181 strains of six species of Candida and 21 strains of Cryptococcus neoformans was carried out in order to investigate the resistance to new antifungal drugs. We have studied clinical isolates from 200 different patients of Hospital del Mar (Barcelona) and Hospital La Inmaculada (Almería). An agar diffusion method (NeoSensitabs, Rosco, Taastrup, Denmark), was employed with fluconazole, itraconazole, and reference drugs amphotericin B, flucytosine, tioconazole and ketoconazole. A high level of susceptibility was found for amphotericin B in C. neoformans strains while 19% of them were resistant to flucytosine. All the strains of C. neoformans and Candida guilliermondii were susceptible to the new azoles derivatives and also Candida parapsilosis and Candida albicans had a great susceptibility to this antifungals. A greater level of resistance was found for Candida krusei, Candida tropicalis and Candida glabrata to fluconazole, itraconazole and ketoconazole, but resistance to fluconazole and itraconazole is not always linked because ten resistant strains for fluconazole were susceptible to itraconazole, and two other resistant to itraconazole were susceptible to fluconazole.  相似文献   

17.
18.
Although only poorly documented, it can be assumed that intensive antibiotic treatments of chronic lung infections in patients with cystic fibrosis (CF) also affect the diversity and metabolic functioning of the gastrointestinal microbiota and potentially lead to a state of dysbiosis. A better knowledge of the differences in gut microbiota composition and stability between patients with CF and healthy subjects could lead to optimization of current antibiotic therapies and/or development of add-on therapies. Using conventional culturing and population fingerprinting by denaturing gradient gel electrophoresis (DGGE) of 16S rRNA amplicons, we compared the predominant fecal microbiota of 21 patients with CF and 24 healthy siblings in a cross-sectional study. General medium counts, as well as counts on media specific for lactic acid bacteria, clostridia, Bifidobacterium spp., Veillonella spp., and Bacteroides-Prevotella spp., were consistently higher in sibling samples than in CF samples, whereas the reverse was found for enterobacterial counts. DGGE fingerprinting uncovered large intersubject variations in both study groups. On the other hand, the cross-sectional data indicated that the predominant fecal microbiota of patients and siblings had comparable species richness. In addition, a longitudinal study was performed on 7 or 8 consecutive samples collected over a 2-year period from two patients and their respective siblings. For these samples, DGGE profiling indicated an overall trend toward lower temporal stability and lower species richness in the predominant fecal CF microbiota. The observed compositional and dynamic perturbations provide the first evidence of a general dysbiosis in children with CF compared to their siblings.  相似文献   

19.
致病酵母菌基因组多态性及亲缘关系的研究   总被引:7,自引:1,他引:6  
致病酵母是条件致病菌感染中最常见的菌群。其属间、种间及种内的分型具有重要的流行病学及临床意义。以随机扩增多态性(Randomly Amplified Polymorphism DNA markers,RAPD)的方法对48株临床上常见的酵母菌属间、种间及种内基因组型的多态性进行了研究,并以多种引物扩增带型的相似性系数的高低来评价酵母菌之间的亲缘关系。结果表明:RAPD带型可清楚的显示出假丝酵母(Candida)及相关酵母属间、种间及种内的差异,亲缘关系的研究表明假丝酵母属与隐球菌属(Cryptococcus)、丝孢酵母属(Trichosporon)的相似性系数为80%,除季也蒙假丝酵母(C. guilliermondii)外,假丝酵母属中不同种间的相似性系数为82%~87%,同种不同株间的相似性系数>90%。大多数属、种基因组分型的结果和形态学分类结果相符。  相似文献   

20.
The opportunistic Candida species existing as part of commensal microbiota in humans are usually the etiological agents causing infections. We investigated whether isolates collected from different age groups, hospital units, and sources have distinct characteristics. A total of 913 isolates comprising 395 Candida albicans, 230 Candida tropicalis, 202 Candida glabrata, 62 Candida parapsilosis, 13 Candida krusei, and 11 of other six species were analyzed. Urine was the most common source (41.2%), followed by sputum (16.3%), blood (15.2%), and others (27.3%). Candida albicans and C. parapsilosis were more prevalent in the working group [from 19 to 65 years], whereas C. tropicalis and C. glabrata were more prevalent in the elder one (≥ 66 years). We found that the age of patients and the source of isolates affect the distribution of species. On the other hand, the drug susceptibility of isolates was associated with fungal species and whether patients were hospitalized.  相似文献   

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