Estimating and testing the effect of allelic recombination on the correlation between genotypic relatives

This paper provides estimates of the correlation between genotypic relatives and the effect of allelic recombination on the correlation assuming random mating. It is shown that the correlation is a non negative quantity and that allelic recombination has the effect of reducing total variation and doubling the correlation between genotypic relatives with respect to measurements on the character of interest. The significance of the correlation coefficient as well as the fitted regression model was obtained using Analysis of Variance method.Key words: Allele, genotype, regression, correlation, F-ratio, analysis of variance

Prevalence and etiology of dermatomycoses among children in Anambra State of Nigeria

Dermatomycoses remain an important public health problem the world over, despite ever-improving therapeutic measures. Information on the pattern of dermatomycoses in Anambra State of Nigeria is sketchy and neccessitates this work. Between 2002 and 2005 a total of 47,723 school children were screened for presence, on the body, of typical dermatomycotic lesions. Of the 47,723 children, 5009 (10.50%) had lesions distributed as follows: Scalp (4498 or 89.80%), glabrous skin (359 or 7.16%), foot (60 or 1.20%) and nail (92 or 1.84%). Schools in rural agricultural parts of the State had high prevalence of the affliction, while those at the urbanized areas had lower prevalence. Scalp infection was significantly more in males than females (P0.05). Children below the age of 10yrs were significantly more afflicted with scalp infection than older children (P 0.10). Of the species isolated, Microsporum audouinii was the most prevalent (38.9%) and was also the predominant cause of scalp infections (40.6%). Microsporum ferrugineum was the commonest cause of skin infections (36.7%). Candida albicans caused the majority of foot infections (80%), as well as nail infections (56%); Trichophyton rubrum was the second major cause of nail infection (44%). There is the need for improvement in living conditions of the population in Anambra State of Nigeria. Journal of Biomedical Investigation Vol. 5 (1) 2007: pp. 1-

isolation of demotiaceous fungi from soil and their pathogenic potentials

No Abstract

Aspectos epidemiológicos de pacientes com lesões ungueais e cutâneas causadas por Scytalidium spp Epidemiological aspects of patients with ungual and cutaneous lesions caused by Scytalidium spp

FUNDAMENTO: As dermatomicoses causadas por fungos filamentosos não dermatófitos são infecções raras, exceto as onicomicoses, cuja prevalência vem crescendo nos últimos anos. Dentre esses agentes etiológicos destacam-se o Scytalidium dimidiatum e o S. hyalinum, fungos emergentes responsáveis por micoses em unhas e pele. OBJETIVO: Investigar as características epidemiológicas das onicomicoses e micoses de outras localizações causadas pelos fungos do gênero Scytalidium, utilizando-se como parâmetros sexo, idade e localizações das lesões. MÉTODOS: Avaliaram-se 81 amostras com cultura positiva para o gênero em estudo, oriundas de 74 pacientes encaminhados ao Laboratório de Investigação em Dermatologia (ID) situado na cidade do Rio de Janeiro (RJ), no período de 1997 a 2006. As amostras foram submetidas a confirmação diagnóstica por exame direto e cultura. RESULTADOS: A prevalência de onicomicoses por Scytalidium spp. foi de 0,87%, entre as idades de 41 e 60 anos (48,64%). Em relação à localização das lesões, os pés foram mais acometidos (91,36%), com predomínio do hálux esquerdo. No exame direto, as estruturas mais encontradas foram hifas hialinas; na cultura, a espécie S. dimidiatum foi a mais frequente. CONCLUSÃO: As onicomicoses por Scytalidium spp. são raras e o S. dimidiatum foi a espécie mais isolada neste laboratório no período em estudo.<br>BACKGROUND: Dermatomycoses caused by non-dermatophyte filamentous fungi are rare infections, except for onychomycosis, whose prevalence has increased over the past few years. Among these etiologic agents, we highlight Scytalidium dimidiatum and S. hyalinum, emergent fungi that cause mycoses that affect the nails and skin. OBJECTIVE: To investigate the characteristics of onychomycosis and other mycoses caused by the fungi Scytalidium spp, using sex, age and site of infection as parameters. METHODS: Eighty-one samples were evaluated showing positive culture for Scytalidium spp, obtained from 74 patients referred to the Laboratory of Investigation in Dermatology (ID) located in the city of Rio de Janeiro, RJ, between 1997 and 2006. The samples were submitted to diagnostic confirmation through direct exam and culture. RESULTS: The prevalence of onychomycosis caused by Scytalidium spp. was of 0,87%. The most prevalent age was between 41-60 years (48.64%). Regarding the site of infection, the feet (91.36%) were most affected, with predominance of the left hallux. Hyaline hyphae were the most common structures in direct examination and the species S. dimidiatum was the most frequent in culture. CONCLUSION: Onychomycosis caused by Scytalidium spp. is rare and S. dimidiatum was the most isolated species in this laboratory during the period of the study