Characterization of the skin fungal microbiota in patients with atopic dermatitis and in healthy subjects

Patients with atopic dermatitis (AD) are highly susceptible to viral, bacterial, and fungal skin infections because their skin is dry and this compromises the barrier function of the skin. Therefore, the skin microbiota of patients with AD is believed to be different from that of healthy individuals. In the present study, the skin fungal microbiota of nine patients with mild, moderate, or severe AD and ten healthy subjects were compared using an rRNA clone library. Fungal D1/D2 large subunit analysis of 3647 clones identified 58 species and seven unknown phylotypes in face scale samples from patients with AD and healthy subjects. Malassezia species were predominant, accounting for 63%-86% of the clones identified from each subject. Overall, the non-Malassezia yeast microbiota of the patients was more diverse than that of the healthy individuals. In the AD samples 13.0 ± 3.0 species per case were detected, as compared to 8.0 ± 1.9 species per case in the samples taken from healthy individuals. Notably, Candida albicans, Cryptococcus diffluens, and Cryptococcus liquefaciens were detected in the samples from the patients with AD. Of the filamentous fungal microbiota, Cladosporium spp. and Toxicocladosporium irritans were the predominant species in these patients. Many pathogenic fungi, including Meyerozyma guilliermondii (anamorphic name, Candida guilliermondii), and Trichosporon asahii, and allergenic microorganisms such as Alternaria alternata and Aureobasidium pullulans were found on the skin of the healthy subjects. When the fungal microbiota of the samples from patients with mild/moderate to severe AD and healthy individuals were clustered together by principal coordinates analysis they were found to be clustered according to health status.     

Characterization of the fungal microbiota (mycobiome) in healthy and dandruff-afflicted human scalps

The human scalp harbors a vast community of microbial mutualists, the composition of which is difficult to elucidate as many of the microorganisms are not culturable using current culture techniques. Dandruff, a common scalp disorder, is known as a causative factor of a mild seborrheic dermatitis as well as pityriasis versicolor, seborrheic dermatitis, and atopic dermatitis. Lipophilic yeast Malassezia is widely accepted to play a role in dandruff, but relatively few comprehensive studies have been reported. In order to investigate fungal biota and genetic resources of dandruff, we amplified the 26S rRNA gene from samples of healthy scalps and dandruff-afflicted scalps. The sequences were analyzed by a high throughput method using a GS-FLX 454 pyrosequencer. Of the 74,811 total sequence reads, Basidiomycota (Filobasidium spp.) was the most common phylum associated with dandruff. In contrast, Ascomycota (Acremonium spp.) was common in the healthy scalps. Our results elucidate the distribution of fungal communities associated with dandruff and provide new avenues for the potential prevention and treatment of dandruff.     

山西省健康人群的肠道菌群组成特征

目的探索山西省健康人群的肠道菌群组成特征及性别和年龄对肠道菌群组成的影响。方法应用16S rRNA基因测序技术,对山西省99名健康个体的粪便细菌DNA进行测序分析。结果山西省健康人群的肠道菌群在属水平分为两个集群,相对丰度最高的分别是拟杆菌属和普氏菌属;在区分这两个集群中,拟杆菌属与普氏菌属的曲线下面积（AUC）分别是0.97、1.00。男性组与女性组的物种丰富度（richness）和多样性（diversity）差异都无统计学意义（均P>0.05）,基于Bray-Curtis距离的主坐标分析（PCoA）图显示两组人群的样本分布没有明显分离（相似性分析：r=-0.0296,P>0.05）,LEfSe分析显示与性别分组有关的细菌很少。30-39岁、40-49岁和50-59岁三组人群的物种丰富度和多样性差异都无统计学意义（均P>0.05）,基于Bray-Curtis距离的PCoA图显示三组人群的样本分布没有明显分离（相似性分析：r=0.0109,P>0.05）,LEfSe分析显示几乎没有与年龄分组有关的细菌。结论山西省健康人群的肠道菌群更倾向分为两种肠型（拟杆菌型和普氏菌型）。性别对肠道菌群组成可能没有显著影响,30-59岁人群的肠道菌群组成比较稳定     

肠道菌群与过敏性哮喘

近年来随着过敏性哮喘发病率的持续升高,人们开始注意到环境、生活方式的改变可能会影响过敏性哮喘的发生。流行病学调查显示,过敏性哮喘的发生和发展与生命早期肠道菌群的紊乱密切相关。本研究主要综述近年来肠道菌群对过敏性哮喘发生的影响及机制,探讨影响肠道菌群定植的主要因素,以及微生态调节剂在过敏性哮喘等变应性疾病中的预防和治疗作用。     

肠道菌群与婴幼儿过敏性疾病

肠道菌群是一个被遗忘的"器官",其在宿主消化营养免疫发育等诸多方面发挥着极为重要的作用。0~3岁是婴幼儿肠道菌群建立的关键时间窗,其与肠道免疫系统的成熟同步,是形成免疫耐受的关键时期,如果这一时期肠道菌群发生紊乱,可导致免疫耐受破坏,引起婴幼儿过敏性疾病。近年来流行病学调查和实验研究提示婴幼儿早期肠道菌群紊乱与过敏性疾病的发生发展密切相关,本研究就婴幼儿常见过敏性疾病如特应性皮炎、食物过敏、哮喘、过敏性鼻炎等与肠道菌群的相关性进行综述。     

Nasal hyperreactivity and inflammation in allergic rhinitis

The history of allergic disease goes back to 1819, when Bostock described his own 'periodical affection of the eyes and chest', which he called 'summer catarrh'. Since they thought it was produced by the effluvium of new hay, this condition was also called hay fever. Later, in 1873, Blackley established that pollen played an important role in the causation of hay fever. Nowadays, the definition of allergy is 'An untoward physiologic event mediated by a variety of different immunologic reactions'. In this review, the term allergy will be restricted to the IgE-dependent reactions. The most important clinical manifestations of IgE-dependent reactions are allergic conjunctivitis, allergic rhinitis, allergic asthma and atopic dermatitis. However, this review will be restricted to allergic rhinitis. The histopathological features of allergic inflammation involve an increase in blood flow and vascular permeability, leading to plasma exudation and the formation of oedema. In addition, a cascade of events occurs which involves a variety of inflammatory cells. These inflammatory cells migrate under the influence of chemotactic agents to the site of injury and induce the process of repair. Several types of inflammatory cells have been implicated in the pathogenesis of allergic rhinitis. After specific or nonspecific stimuli, inflammatory mediators are generated from cells normally found in the nose, such as mast cells, antigen-presenting cells and epithelial cells (primary effector cells) and from cells recruited into the nose, such as basophils, eosinophils, lymphocytes, platelets and neutrophils (secondary effector cells). This review describes the identification of each of the inflammatory cells and their mediators which play a role in the perennial allergic processes in the nose of rhinitis patients.     

Abundant and diverse fungal microbiota in the murine intestine

Enteric microbiota play a variety of roles in intestinal health and disease. While bacteria in the intestine have been broadly characterized, little is known about the abundance or diversity of enteric fungi. This study utilized a culture-independent method termed oligonucleotide fingerprinting of rRNA genes (OFRG) to describe the compositions of fungal and bacterial rRNA genes from small and large intestines (tissue and luminal contents) of restricted-flora and specific-pathogen-free mice. OFRG analysis identified rRNA genes from all four major fungal phyla: Ascomycota, Basidiomycota, Chytridiomycota, and Zygomycota. The largest assemblages of fungal rRNA sequences were related to the genera Acremonium, Monilinia, Fusarium, Cryptococcus/Filobasidium, Scleroderma, Catenomyces, Spizellomyces, Neocallimastix, Powellomyces, Entophlyctis, Mortierella, and Smittium and the order Mucorales. The majority of bacterial rRNA gene clones were affiliated with the taxa Bacteroidetes, Firmicutes, Acinetobacter, and Lactobacillus. Sequence-selective PCR analyses also detected several of these bacterial and fungal rRNA genes in the mouse chow. Fluorescence in situ hybridization analysis with a fungal small-subunit rRNA probe revealed morphologically diverse microorganisms resident in the mucus biofilm adjacent to the cecal and proximal colonic epithelium. Hybridizing organisms comprised about 2% of the DAPI (4',6-diamidino-2-phenylindole, dihydrochloride)-positive organisms in the mucus biofilm, but their abundance in fecal material may be much lower. These data indicate that diverse fungal taxa are present in the intestinal microbial community. Their abundance suggests that they may play significant roles in enteric microbial functions.     

浅部真菌感染和变态反应性皮肤病相关性研究

目的 通过比较合并与未合并浅部真菌感染的变态反应性皮肤病对常用变应原的敏感性,综合从皮肤或指(趾)甲中分离出的菌种情况,评估浅部真菌感染在变态反应性皮肤病的病因学中的作用.方法 受试者包括353例慢性荨麻疹、湿疹及特应性皮炎患者.通过真菌直接镜检法将受试者分为两组.实验组:变态反应性皮肤病合并浅部真菌感染组(n =173);对照组:变态反应性皮肤病无浅部真菌感染组(n=180).对所有实验组及对照组受试者进行9种真菌变应原和9种非真菌变应原皮内试验.实验组患者进一步进行真菌培养以鉴定菌种.结果 慢性荨麻疹患者实验组须发癣菌、新月弯孢霉,特异青霉、烟曲霉变应原阳性率显著高于对照组(P＜0.05),慢性湿疹患者实验组须发癣菌变应原阳性率显著高于对照组(P ＜0.001).慢性湿疹、荨麻疹患者其他真菌变应原及粉尘螨、屋尘螨等非真菌变应原阳性率比较差异均无统计学意义(P＞0.05).134例患者皮肤或指(趾)甲分离鉴定主要为红色毛癣菌(52.86％)、须癣毛癣菌(14.18％)、絮状表皮癣菌(5.22％)、白念珠菌(6.72％),实验组须发癣菌变应原阳性率及皮肤分离皮肤癣菌阳性率比较差异无统计学意义(P＞0.05).结论 实验结果表明,须发癣菌变应原阳性的慢性荨麻疹、湿疹患者往往合并皮肤癣菌感染,皮肤癣菌感染可能在部分慢性荨麻疹、湿疹的病因学中起重要作用.     

Update on allergic fungal rhinosinusitis

The combination of nasal polyposis, crust formation, and sinus cultures yielding Aspergillus was first noted in 1976 by Safirstein, who observed the clinical similarity that this constellation of findings shared with allergic bronchopulmonary Aspergillosis. Eventually this disease came to be known as allergic fungal rhinosinusitis (AFRS). As clinical evidence on AFRS continues to accumulate, controversy regarding its etiology, pathogenesis, natural history, and appropriate treatment naturally has emerged. Despite past and current efforts, many of these controversies remain incompletely resolved, but continuing clinical study has illuminated some aspects of the disease and has led to an improved understanding of AFRS and its treatment. This article is intended to review current data and theories regarding the pathophysiology and clinical presentation of AFRS, as well as the role of various surgical and nonsurgical forms of therapy.     

Molecular monitoring of the fecal microbiota of healthy human subjects during administration of lactulose and Saccharomyces boulardii

Diet is a major factor in maintaining a healthy human gastrointestinal tract, and this has triggered the development of functional foods containing a probiotic and/or prebiotic component intended to improve the host's health via modulation of the intestinal microbiota. In this study, a long-term placebo-controlled crossover feeding study in which each subject received several treatments was performed to monitor the effect of a prebiotic substrate (i.e., lactulose), a probiotic organism (i.e., Saccharomyces boulardii), and their synbiotic combination on the fecal microbiota of three groups of 10 healthy human subjects differing in prebiotic dose and/or intake of placebo versus synbiotic. For this purpose, denaturing gradient gel electrophoresis (DGGE) analysis of 16S rRNA gene amplicons was used to detect possible changes in the overall bacterial composition using the universal V(3) primer and to detect possible changes at the subpopulation level using group-specific primers targeting the Bacteroides fragilis subgroup, the genus Bifidobacterium, the Clostridium lituseburense group (cluster XI), and the Clostridium coccoides-Eubacterium rectale group (cluster XIVa). Although these populations remained fairly stable based on DGGE profiling, one pronounced change was observed in the universal fingerprint profiles after lactulose ingestion. Band position analysis and band sequencing revealed that a band appearing or intensifying following lactulose administration could be assigned to the species Bifidobacterium adolescentis. Subsequent analysis with real-time PCR (RT-PCR) indicated a statistically significant increase (P < 0.05) in total bifidobacteria in one of the three subject groups after lactulose administration, whereas a similar but nonsignificant trend was observed in the other two groups. Combined RT-PCR results from two subject groups indicated a borderline significant increase (P = 0.074) of B. adolescentis following lactulose intake. The probiotic yeast S. boulardii did not display any detectable universal changes in the DGGE profiles, nor did it influence the bifidobacterial levels. This study highlighted the capacity of an integrated approach consisting of DGGE analysis and RT-PCR to monitor and quantify pronounced changes in the fecal microbiota of healthy subjects upon functional food administration.     

Bifidobacterium microbiota and parameters of immune function in elderly subjects

Faecal and serum samples were collected over a period of 6 months from 55 institutionalized elderly subjects, who were enrolled in a double-blind placebo-controlled study. Participants were randomized in one of the three treatment groups: intervention (two probiotic Bifidobacterium longum strains: 2C and 46), placebo and commercial control (Bifidobacterium lactis Bb-12). The faecal Bifidobacterium microbiota was characterized by genus and species-specific PCR. Serum levels of the cytokines IL-10, tumor necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta1 were determined by enzyme-linked immunosorbent assay. Each participant harboured on average approximately three different bifidobacterial species. The most frequently detected species were B. longum, Bifidobacterium adolescentis and Bifidobacterium bifidum. Depending on the treatment, the intervention resulted in specific changes in the levels of certain Bifidobacterium species, and positive correlations were found between the different species. Negative correlations were observed between the levels of Bifidobacterium species and the pro-inflammatory cytokine TNF-alpha and the regulatory cytokine IL-10. The presence of faecal B. longum and Bifidobacterium animalis correlated with reduced serum IL-10. The anti-inflammatory TGF-beta1 levels were increased over time in all three groups, and the presence of Bifidobacterium breve correlated with higher serum TGF-beta1 levels. This indicates that modulation of the faecal Bifidobacterium microbiota may provide a means of influencing inflammatory responses.     

肠道微生物群在人类健康衰老中的作用机制研究进展北大核心

衰老的特征是组织器官的功能衰退以及衰老相关疾病风险的增加,这给维护和促进健康长寿带来一系列新的挑战。尽管进行了广泛的衰老相关研究,但进展有限。人们越来越意识到肠道微生物群的结构和功能积极参与了衰老过程。肠道微生物群紊乱表现为许多与年龄相关的肠外器官轴的衰老。肠道微生物群可以被调节,这暗示了通过肠道微生物群抗衰老是一个可以实现的重要目标。本综述总结了肠道微生物群在不同年龄段中的动态演替,这种动态的肠道微生物群从胎儿到出生和婴儿期开始迅速发展,从断奶期到幼儿期迅速变化,然后建立稳定的成年人菌群,直到随着年龄增长最后发生衰退;肠道微生物群与肠外器官轴(大脑、心脏、肝脏、胰腺、肌肉、皮肤和骨骼)衰老相关疾病,以及通过饮食、粪菌移植和微生态制剂调节肠道微生物群靶向抗衰老的研究进展,以期为调控肠道微生物群抗衰老研究提供参考。     

Dermatoglyphic asymmetry in healthy and pathological subjects

The amount of asymmetry in various digital and palmar characters found in healthy and pathological individuals (presenting Cooley's anemia, cleft lip, cleft palate and breast cancer) was examined. Males with cleft palate presented higher asymmetry index values than did healthy males. No great differences were found in the other pathologies, while different behaviour in the two sexes was noted. Work supported by M.U.R.S.T. 60%     

The fungal microbiota of de-novo paediatric inflammatory bowel disease

Inflammatory bowel disease (IBD) is characterised by an inappropriate chronic immune response against resident gut microbes. This may be on account of distinct changes in the gut microbiota termed as dysbiosis. The role of fungi in this altered luminal environment has been scarcely reported. We studied the fungal microbiome in de-novo paediatric IBD patients utilising next generation sequencing and compared with adult disease and normal controls. We report a distinct difference in fungal species with Ascomycota predominating in control subjects compared to Basidiomycota dominance in children with IBD, which could be as a result of altered tolerance in these patients.     

Changes in fecal microbiota of healthy dogs administered amoxicillin

The effect of oral amoxicillin treatment on fecal microbiota of seven healthy adult dogs was determined with a focus on the prevalence of bacterial antibiotic resistance and changes in predominant bacterial populations. After 4–7 days of exposure to amoxicillin, fecal Escherichia coli expressed resistance to multiple antibiotics when compared with the pre-exposure situation. Two weeks postexposure, the susceptibility pattern had returned to pre-exposure levels in most dogs. A shift in bacterial populations was confirmed by molecular fingerprinting of fecal bacterial populations using denaturing gradient gel electrophoresis (PCR-DGGE) of the 16S V3 rRNA gene region. Much of the variation in DGGE profiles could be attributed to dog-specific factors. However, permutation tests indicated that amoxicillin exposure significantly affected the DGGE profiles after controlling for the dog effect ( P =0.02), and pre-exposure samples were clearly separated from postexposure samples. Sequence analysis of DGGE bands and real-time PCR quantification indicated that amoxicillin exposure caused a shift in the intestinal ecological balance toward a Gram-negative microbiota including resistant species in the family Enterobacteriaceae .