Antifungal Activity of the Essential Oils of Osteophloeum platyspermum (Myristicaceae) against Malassezia spp. and Candida albicans Influenced by Seasonality and Climatic Factors

Aims: Malassezia spp. are involved in a wide range of mammalian skin diseases. The introduction of new drugs is a need. Natural products are known to be effective in the treatment of microbial pathogens. The present study analyzed the O. platyspermum leaf essential oils (EOs) antifungal activity. Study Design: 18 terpenes from 13 O. platyspermum leaf EOs are related to seasonal and climatic variations occurring during the dry (DS) and rainy (RS) seasons in the Amazon Rain-Forest, verified by means of multivariate analyses. Place and Duration of the Study: the study was conducted at the Center for Research in Biodiversity (Microbiology Laboratory and Cell Culture Laboratory), Paulista University, biological activity evaluations occurred between January/2019 and December 2019). Methodology: microdilution broth assay was used in the minimal bactericidal concentration (MBC). Multivariate analyses were used to access the relationship among MBC, seasonality and terpene composition of the EOs. Results: Malassezia pachydermatis showed higher sensitivity to the EOs than M. furfur or C. albicans. The DS EOs were linked to the presence of limonene, myrcene, α-terpineol, linalool, terpinen-4-ol, cubenol-1-epi, influenced by insolation, temperature and evaporation, while β-elemene, γ-elemene, neo-intermedeol, elemol, α-cadinol, spathulenol, isospathulenol, viridiflorol, δ-amorphene and ledol were linked to the RS EOs, and were influenced by precipitation, relative humidity and wind velocity. DS EOs showed better antifungal activity against both Malassezia species, and the presence of the six discriminative terpenes was essential for the antifungal activity. Conclusions: The DS EOs are a potential source of new leads to defeat animal dermatological microbes.

Chronic Diseases Associated with Malassezia Yeast

Malassezia are a lipid-dependent basidiomycetous yeast of the normal skin microbiome, although Malassezia DNA has been recently detected in other body sites and has been associated with certain chronic human diseases. This new perspective raises many questions. Are these yeasts truly present in the investigated body site or were they contaminated by other body sites, adjacent or not? Does this DNA contamination come from living or dead yeast? If these yeasts are alive, do they belong to the resident mycobiota or are they transient colonizers which are not permanently established within these niches? Finally, are these yeasts associated with certain chronic diseases or not? In an attempt to shed light on this knowledge gap, we critically reviewed the 31 published studies focusing on the association of Malassezia spp. with chronic human diseases, including psoriasis, atopic dermatitis (AD), chronic rhinosinusitis (CRS), asthma, cystic fibrosis (CF), HIV infection, inflammatory bowel disease (IBD), colorectal cancer (CRC), and neurodegenerative diseases.

Identification of Malassezia Species in Seborrheic Dermatitis Patients by CHROM Agar-Medium

Background Seborrheic dermatitis (SD) is a subacute or chronic superficial inflammatory skin condition, characterized by pruritic, erythematous plaques with greasy, yellow-gray scales, which appear on areas rich in sebaceous glands such as the face, scalp, upper chest, and back. Aim of the Work To identify Malassezia species that are involved in the development of SD in different body sites (face, scalp and trunk) and in different age groups, by using Chrom agar. Patients and Methods Forty nine patients with seborrheic dermatitis attending dermatology outpatient clinic in Ain shams university hospital the samples collected from December 2018 to June 2019. Results In this study, the most affected areas were the scalp and other sites as face and ears, which is concordant with the majority of studies worldwide. The role of sex in propensity to the development of Malassezia spp. Infection in SD is still unclear. Conclusion The distribution of Malassezia spp. on healthy and diseased skin shows significant variation and differences, although our knowledge of Malassezia yeasts has increased tremendously during the last two decades, their pathological roles remain ambiguous, and there is currently no conclusive evidence that any given species is responsible for a specific disease.

Diagnosis and therapeutic management of malasseziosis in dogs

Malassezia spp. are commensals of the normal cutaneous microbiota of humans and animals. These yeasts may become opportunistic pathogens under certain conditions and cause dermatitis and otitis externa in dogs. Malassezia pachydermatis is the most common cause of malasseziosis in dogs. In this study skin and ear swabs from suspected cases were cultured on Modified Dixon’s Agar (MDA). The isolates obtained were initially characterized on the basis of colony characteristics, result of Gram staining and microscopic morphology. Total DNA was extracted from the pure cultures of the isolates and subjected to confirmation by polymerase chain reaction (PCR) targeting large subunit ribosomal RNA gene. Positive cases were treated with oral itraconazole at 5 mg/kg bodyweight, orally once daily for 28 days.

Chronic Diseases Associated with Malassezia Yeast

Malassezia are lipid-dependent basidiomycetous yeast of the normal skin microbiome, although Malassezia DNA has been recently detected in other body sites and has been associated with cer-tain chronic human diseases. This new perspective raises many questions. Are these yeasts truly present in the investigated body site or were they contaminated by other body sites, adjacent or not? Does this DNA contamination come from living or dead yeast? If these yeasts are alive, do they belong to the resident mycobiota or are they transient colonizers which are not permanently established within these niches? And, finally, are these yeasts associated with certain chronic diseases or not? In an attempt to shed light on this knowledge gap, we critically re-viewed the 31 published studies focusing on the association of Malassezia spp. with chronic human diseases, including psoriasis, atopic dermatitis (AD), chronic rhinosinusitis (CRS), asthma, cystic fibrosis (CF), HIV infection, inflammatory bowel disease (IBD), colorectal cancer (CRC), and neurodegenerative diseases.

Utilização do exame citológico no diagnóstico de afecções de cães e gatos

Este trabalho verificou a utilização do diagnóstico citológico, como método de identificação de afecções em cães e gatos domiciliados no município de Barra-BA atendidos no Hospital Veterinário Universitário (HVU) da Universidade Federal do Oeste da Bahia (UFOB). O estudo foi realizado a partir da análise de amostras citológicas relativas aos casos clínicos atendidos nos anos de 2018 e 2019. Foram atendidos 711 animais, desses contabilizadas 105 (101 caninos e 4 felinos - 59 fêmeas e 46 machos) solicitações do exame citológico. A maioria dos animais (28,57%) apresentavam de 6 a 10 anos, prevalecendo os animais Sem Raça Definida (62,38%). Os processos inflamatórios foram diagnosticados em 43,80% dos casos, identificados como de causa infecciosa em 86,90% (30% por Leishmania spp., 27,5% infecções bacterianas, 27,5% pela levedura Malassezia spp. e outros 15% por associação deste fungo a bactérias). Os processos inflamatórios de origem não infecciosa foram registrados em 13,10% casos (84% infiltrados de células inflamatórias e 16% como dermatite por lambedura). Observou-se processos não inflamatórios em 19,05% das amostras, sendo 95% de origem neoplásica, (63,15% TVT, 21,05% Carcinoma de Células Escamosas, 10,05% Adenocarcinoma e 5,30% Tricoblastoma). Já entre os processos não inflamatórios e não neoplásicos (5%) diagnosticou-se um cisto epidérmico (100%). A aplicabilidade do diagnóstico citológico em cães e gatos denota importância uma vez que, auxiliou médicos veterinários na confirmação de suspeitas clínicas, permitindo a emissão de laudos diagnósticos, estabelecimento de tratamentos e dados epidemiológicos que possibilitam a implantação de medidas de controle das enfermidades.

Association of Fungi and Archaea of the Gut Microbiota with Crohn’s Disease in Pediatric Patients—Pilot Study

The composition of bacteria is often altered in Crohn’s disease (CD), but its connection to the disease is not fully understood. Gut archaea and fungi have recently been suggested to play a role as well. In our study, the presence and number of selected species of fungi and archaea in pediatric patients with CD and healthy controls were evaluated. Stool samples were collected from children with active CD (n = 54), non-active CD (n = 37) and control subjects (n = 33). The prevalence and the number of selected microorganisms were assessed by real-time PCR. The prevalence of Candida tropicalis was significantly increased in active CD compared to non-active CD and the control group (p = 0.011 and p = 0.036, respectively). The number of Malassezia spp. cells was significantly lower in patients with active CD compared to the control group, but in non-active CD, a significant increase was observed (p = 0.005 and p = 0.020, respectively). There were no statistically significant differences in the colonization by archaea. The obtained results indicate possible correlations with the course of the CD; however, further studies of the entire archeobiome and the mycobiome are necessary in order to receive a complete picture.

​Evaluation of Fungi Isolated in the Veterinary Microbiology Laboratory in Terms of Human Health

Background: The importance of zoonotic fungal infections is increasing today and continues to increase due to changing living conditions. Methods: Between 2012 and 2019 evaluated of fungi species isolated from 51 (20.07%) of 254 samples from 10 different animal species (dog, cat, horse, cow, goat, sheep, camel, penguin, bird, rabbit) with 10 different sample types Thus, the risk of those with zoonotic characteristics was assessed. Despite fungal hyphae and/or spores were seen in 63 (24.8%) of 254 samples in the direct microscopic examination, the isolation of fungi on Sabouraud dextrose agar occurred in only 51 of these samples (20.07%). Conclusion: Of all the 51 samples, 9 (17.64%) samples had more than one fungal agent. The predominant isolate was Aspergillus spp. with an isolation rate of 24 (47.05%), followed by Malassezia spp. 11 (21.56%), Alternaria spp. 6 (11.76%), Penicillium spp. and various yeasts 4 (7.84%), Microsporum spp. 3 (5.88%), Candida spp., Mucor spp., Geotrichum spp. 2 (3.92%) and Trichophyton spp. and Rhizopus spp. 1 (1.96%). Besides, samples were examined for the presence of bacteria and one or more of the bacteria were also isolated from 14 (27.4%) of 51 samples. This assessment in the veterinary microbiology laboratory has shown that the isolated fungi agents pose a significant risk of infection for people who take care of these animals or consume animal products and pet owners.

Features of management of patients with seborrheic dermatitis

Seborrheic dermatitis (SD) is a chronic recurrent inflammatory skin disease caused by changes of quantitative and qualitative sebum characteristics. SD comes out by appearing of erythematous plaques with sense of itch and peeling skin in areas with high concentration of sebaceous glands: on the scalp, face, upper part of the body and in the folds of skin. Due to the fact that the development of the SD is promoted by the colonization of the skin with a lipophilic yeast fungus Malassezia spp., in the treatment of uncomplicated simple forms of the disease can be applied external antifungal medicines, topical glucocorticosteroids and anti-inflammatory drugs of non-steroidal origin. Systemic therapy is also used in severe course of seborrheic dermatitis and in the treatment of forms, resistant to external therapy. In the treatment of persistent and long-term forms of SD, systemic antifungal agents and systemic retinoids are used, which allow for a long time to achieve regression of skin rashes and significantly improve the quality of life of the patient.