Study of the distribution of Malassezia species in patients with pityriasis versicolor and healthy individuals in Tehran, Iran

BACKGROUND: Pityriasis versicolor is a superficial infection of the stratum corneum which caused by a group of yeasts formerly named pityrosporium. The taxonomy of these lipophilic yeasts has recently been modified and includes seven species referred as Malassezia. The aim of this study is to compare the distribution of Malassezia species isolated from pityriasis versicolor lesions and those isolated from healthy skins. METHODS: Differentiation of all malassezia species performed using morphological features and physiological test including catalase reaction, Tween assimilation test and splitting of esculin. RESULTS: In pityriasis versicolor lesions, the most frequently isolated species was M. globosa (53.3%), followed by M. furfur (25.3%), M. sympodialis(9.3%), M. obtusa (8.1%) and M. slooffiae (4.0%). The most frequently isolated species in the skin of healthy individuals were M. globosa, M. sympodialis, M. furfur, M. sloofiae and M. restricta which respectively made up 41.7%, 25.0%, 23.3%, 6.7% and 3.3% of the isolated species. CONCLUSIONS: According to our data, M. globosa was the most prevalent species in the skin of healthy individuals which recovered only in the yeast form. However, the Mycelial form of M. globosa was isolated as the dominant species from pityriasis versicolor lesions. Therefore, the role of predisposing factors in the conversion of this yeast to mycelium and its subsequent involvement in pityriasis versicolor pathogenicity should be considered

Facial Skin Coloration Affects Perceived Health of Human Faces

Numerous researchers have examined the effects of skin condition, including texture and color, on the perception of health, age, and attractiveness in human faces. They have focused on facial color distribution, homogeneity of pigmentation, or skin quality. We here investigate the role of overall skin color in determining perceptions of health from faces by allowing participants to manipulate the skin portions of color-calibrated Caucasian face photographs along CIELab color axes. To enhance healthy appearance, participants increased skin redness (a*), providing additional support for previous findings that skin blood color enhances the healthy appearance of faces. Participants also increased skin yellowness (b*) and lightness (L*), suggesting a role for high carotenoid and low melanin coloration in the healthy appearance of faces. The color preferences described here resemble the red and yellow color cues to health displayed by many species of nonhuman animals

Testing in Mice the Hypothesis That Melanin Is Protective in Malaria Infections

Malaria has had the largest impact of any infectious disease on shaping the human genome, exerting enormous selective pressure on genes that improve survival in severe malaria infections. Modern humans originated in Africa and lost skin melanization as they migrated to temperate regions of the globe. Although it is well documented that loss of melanization improved cutaneous Vitamin D synthesis, melanin plays an evolutionary ancient role in insect immunity to malaria and in some instances melanin has been implicated to play an immunoregulatory role in vertebrates. Thus, we tested the hypothesis that melanization may be protective in malaria infections using mouse models. Congenic C57BL/6 mice that differed only in the gene encoding tyrosinase, a key enzyme in the synthesis of melanin, showed no difference in the clinical course of infection by Plasmodium yoelii 17XL, that causes severe anemia, Plasmodium berghei ANKA, that causes severe cerebral malaria or Plasmodium chabaudi AS that causes uncomplicated chronic disease. Moreover, neither genetic deficiencies in vitamin D synthesis nor vitamin D supplementation had an effect on survival in cerebral malaria. Taken together, these results indicate that neither melanin nor vitamin D production improve survival in severe malaria

Gastrointestinal decontamination in the acutely poisoned patient

ObjectiveTo define the role of gastrointestinal (GI) decontamination of the poisoned patient.Data sourcesA computer-based PubMed/MEDLINE search of the literature on GI decontamination in the poisoned patient with cross referencing of sources.Study selection and data extractionClinical, animal and in vitro studies were reviewed for clinical relevance to GI decontamination of the poisoned patient.Data synthesisThe literature suggests that previously, widely used, aggressive approaches including the use of ipecac syrup, gastric lavage, and cathartics are now rarely recommended. Whole bowel irrigation is still often recommended for slow-release drugs, metals, and patients who "pack" or "stuff" foreign bodies filled with drugs of abuse, but with little quality data to support it. Activated charcoal (AC), single or multiple doses, was also a previous mainstay of GI decontamination, but the utility of AC is now recognized to be limited and more time dependent than previously practiced. These recommendations have resulted in several treatment guidelines that are mostly based on retrospective analysis, animal studies or small case series, and rarely based on randomized clinical trials.ConclusionsThe current literature supports limited use of GI decontamination of the poisoned patient

Mortes evitáveis em vítimas com traumatismos

OBJETIVO: Descrever métodos e estimativas de mortalidade proporcional por mortes evitáveis e tipos de não conformidades do atendimento relacionadas a esses eventos. MÉTODOS: Revisão sistemática de publicações sobre mortes evitáveis em vítimas com traumatismos entre 2000 e 2009. Foi realizada pesquisa nas bases de dados Lilacs, SciELO e Medline utilizando-se a estratégia de busca com as palavras-chave "trauma", "avoidable", "preventable", "interventions" e "complications", e os descritores em ciências da saúde "death", "cause of death" e "hospitals". RESULTADOS: Identificaram-se 29 artigos publicados no período, com predomínio de estudos retrospectivos (96,5%). Os métodos mais comumente utilizados para definir a evitabilidade do óbito foram painel de especialistas ou pontuação de índices de gravidade, tendo sido empregadas as seguintes categorias: evitável, potencialmente evitável e não evitável. A média da mortalidade proporcional por mortes evitáveis dos estudos foi de 10,7% (dp 11,5%). As não conformidades mais comumente relatadas nas publicações foram sistema inadequado de atendimento ao traumatizado e erro na avaliação e tratamento. CONCLUSÕES: Observaram-se falhas na uniformização dos termos empregados para categorizar as mortes e as não conformidadades encontradas. Portanto, sugere-se a padronização da taxonomia da classificação das mortes e dos tipos de não conformidades observadas

Co-operative inhibitory effects of hydrogen peroxide and iodine against bacterial and yeast species.

BACKGROUND: Hydrogen peroxide and iodine are powerful antimicrobials widely used as antiseptics and disinfectants. Their antimicrobial properties are known to be enhanced by combining them with other compounds. We studied co-operative inhibitory activities (synergism, additive effects and modes of growth inhibition) of hydrogen peroxide and iodine used concurrently against 3 bacterial and 16 yeast species. RESULTS: Synergistic or additive inhibitory effects were shown for hydrogen peroxide and iodine mixtures against all 19 species used in the study. Both biocides were mostly cidal individually and in mixtures against Pseudomonas aeruginosa and Staphylococcus aureus. Both compounds manifested static inhibitory effects individually, but their mixtures were synergistically cidal for Saccharomyces cerevisiae and Escherihia coli. Cells of S. cerevisiae treated with hydrogen peroxide and iodine-hydrogen peroxide mixture produced increased numbers of respiratory deficient mutants indicating genotoxic effects. CONCLUSION: Iodine and hydrogen peroxide used concurrently interact synergistically or additively against a range of prokaryotic and eukaryotic microorganisms. The study provides an insight as to how these traditional antimicrobials could be used more effectively for disinfection and antisepsis. In addition, a simple approach is proposed for scoring genotoxicity of different biocides by using the budding yeast system

The role of flavor and fragrance chemicals in TRPA1 (transient receptor potential cation channel, member A1) activity associated with allergies

TRPA1 has been proposed to be associated with diverse sensory allergic reactions, including thermal (cold) nociception, hearing and allergic inflammatory conditions. Some naturally occurring compounds are known to activate TRPA1 by forming a Michael addition product with a cysteine residue of TRPA1 through covalent protein modification and, in consequence, to cause allergic reactions. The anti-allergic property of TRPA1 agonists may be due to the activation and subsequent desensitization of TRPA1 expressed in sensory neurons. In this review, naturally occurring TRPA1 antagonists, such as camphor, 1,8-cineole, menthol, borneol, fenchyl alcohol and 2-methylisoborneol, and TRPA1 agonists, including thymol, carvacrol, 1’S-1’- acetoxychavicol acetate, cinnamaldehyde, α-n-hexyl cinnamic aldehyde and thymoquinone as well as isothiocyanates and sulfides are discussed