Assessing the Threat of Amphibian Chytrid Fungus in the Albertine Rift: Past, Present and Future.

Batrachochytrium dendrobatidis (Bd), the cause of chytridiomycosis, is a pathogenic fungus that is found worldwide and is a major contributor to amphibian declines and extinctions. We report results of a comprehensive effort to assess the distribution and threat of Bd in one of the Earth's most important biodiversity hotspots, the Albertine Rift in central Africa. In herpetological surveys conducted between 2010 and 2014, 1018 skin swabs from 17 amphibian genera in 39 sites across the Albertine Rift were tested for Bd by PCR. Overall, 19.5% of amphibians tested positive from all sites combined. Skin tissue samples from 163 amphibians were examined histologically; of these two had superficial epidermal intracorneal fungal colonization and lesions consistent with the disease chytridiomycosis. One amphibian was found dead during the surveys, and all others encountered appeared healthy. We found no evidence for Bd-induced mortality events, a finding consistent with other studies. To gain a historical perspective about Bd in the Albertine Rift, skin swabs from 232 museum-archived amphibians collected as voucher specimens from 1925-1994 were tested for Bd. Of these, one sample was positive; an Itombwe River frog (Phrynobatrachus asper) collected in 1950 in the Itombwe highlands. This finding represents the earliest record of Bd in the Democratic Republic of Congo. We modeled the distribution of Bd in the Albertine Rift using MaxEnt software, and trained our model for improved predictability. Our model predicts that Bd is currently widespread across the Albertine Rift, with moderate habitat suitability extending into the lowlands. Under climatic modeling scenarios our model predicts that optimal habitat suitability of Bd will decrease causing a major range contraction of the fungus by 2080. Our baseline data and modeling predictions are important for comparative studies, especially if significant changes in amphibian health status or climactic conditions are encountered in the future.

Robert Remak (1815-1865): discoverer of the fungal character of dermatophytoses.

Robert Remak was the first scientist to undertake successful research on fungal skin infections. A neurologist, physiologist, and embryologist, Remak was the first to observe the fungal changes causing the disease of favus; however, he gave credit for the discovery to Professor Johann Schönlein and denied all attempts by others to credit him with the discovery by calling them a mistake. He named the disease Achorion schönleinii; however, over time, the name was changed to Trichophyton schoenleinii. Remak also described axial fibers encased in a medullary sheath and was the first to recognize nonmyelated (sympathetic) nerve fibers, today called fibers of Remak. He demonstrated the existence of the medullary nerve sheath and its production in the process of structured cell division. Remak also was the first to demonstrate that the cerebral cortex consists of six layers and to assert that there are three germ layers in the early embryo and not four.

Celalettin Muhtar Ozden (1865-1947): his life, works and contributions to the study of dermatophytes.

BACKGROUND: Most of the distinctive studies concerning dermatophyte infections were carried out at the end of the 19(th) century. One of the contributors of these studies was the Turkish dermatologist Dr. Celalettin Muhtar Ozden. The aim of this study was to introduce his life, works, and contributions to dermatology. METHODS: Dr. Ozden's original works and published memories about him were evaluated. RESULTS: After graduating from the Military Medical School he was sent to Paris to carry out his studies on skin and syphilitic diseases in 1889 by the School. During his practice in Dr. A. Fournier's dermatological clinic at St. Louis Hospital (1889-1892), he diagnosed cases of trichophytosis that affects hands and feet. He published his findings collectively, in which, he presented information regarding the distinctive diagnosis and treatment of the disease, through a series of 25 cases, 18 of which were observed by himself in 1892. After returning to his homeland, Dr. Ozden trained many medical students through the last years of the Ottoman Empire to the first years of the Republic of Turkey. CONCLUSION: His publication dated 1892 is characterized by being the first detailed work on dermatophyte infections affecting hands and feet. Today, he is well known by dermatologists in Turkey and his name has been immortalized through the term, the 'Celal Muhtar's disease.' It is important that this famous Turkish physician should keep his rightful place in the medical history of the world as well.

Historical aspects of dermatomycoses.

Physicians have been aware of superficial fungal infections for centuries, but the causal agents and treatments of fungal infections remained unknown until the mid-1800s, when numerous important findings were reported. Among the relevant researchers in the field of superficial mycoses were Remak, who found the fungal nature of favus in 1837; Berg, who reported oral candidosis in 1841; and Wilkinson, who described vaginal candidosis in 1849. Tinea versicolor was described clinically in 1846 by Eichstedt, and its etiologic agent was identified in 1853. Beigel reported white piedra in 1856, and Cerqueira, tinea nigra in 1891. The book Les Tiegnes was published by Sabouraud in 1910, and black piedra infection was described by Horta in 1911. In 1927, Nannizzi reported the description of the sexual state of Microsporum gypseum. The current classification of dermatophytes was published by Emmons in 1934, and the taxonomy of yeast fungi was described by Lodder and Kreger-van Rij in 1952. Finally, the successful treatment of tinea capitis with griseofulvin by Gentles in 1958 saved many patients with tinea capitis from permanent hair loss, a common side effect after treatment with thallium. (c) 2010 Elsevier Inc. All rights reserved.

Dermatofitias en niños: revisión retrospectiva de 487 casos en Tucumán-Argentina / Dermatophytoses in children: retrospective revision of 487 cases in Tucumán-Argentina

Los hongos dermatofitos son los agentes causales más frecuentes de micosis . No obstante, la prevalencia de los agentes causales varía en las regiones geográficas, las características demográficas de la población estudiada y la metodología de laboratorio. A fin de determinar la frecuencia de dermatofitos en niños de Tucumán (R. Argentina), se presentan los resultados de una revisión retrospectiva de 9 años (2000-2008) de los protocolos médicos de 712 niños de 0 a 14 años de edad, (413 varones y 299 mujeres), con diagnóstico clínico de micosis en piel, uñas, pelos y cuero cabelludo evaluados en el Hospital del Niño Jesús. Las tineas fueron diagnosticadas en 487 pacientes (68,4 por ciento), predominando en el género masculino. La distribución de los hongos aislados fue: M. canis (78,4 por ciento), T. mentagrophytes (6,4 por ciento), T. rubrum (6,2 por ciento),T. tonsurans (4,5 por ciento), M. gypseum (3,9 por ciento), T. mentagrophytes var. interdigitale (0,4 por ciento) y E. floccosum (0,2 por ciento). Coincidentemente con trabajos previos realizados en nuestra provincia, la tinea capitis es la afección predominante y M. canis sigue siendo su principal agente patógeno más frecuente (93,8 por ciento). La alta proporción de aislamientos de M. canis, indica claramente que las especies zoofílicas son las más prevalentes en nuestra área. El grupo etario de mayor incidencia fue el de 0 a 3 años seguido del grupo de 4 a 6 años de edad.

Dermatophyte fungi are the most frequent agents causing mycosis. However prevalence of the causing agents varies with the geographic regions, demographic characteristics of the studied population and with the laboratory methodology. In order to determine the incidence of Dermatophytes in chidren of Tucumán (R. Argentina), results of a 9-year retrospective revision (2000-2008) of the medical protocols of 712 children of 0 to 14 years of age (413 men and 299 women) diagnosed with mycosis in hair, scalp, skin and nails are reported and who had been evaluated in the Hospital del Niño Jesús. Tinea were diagnosed in 487 patients (68.4 percent), prevailing in the masculine genus. The distribution of isolated fungi was: M.canis, (78.4 percent), T.mentagrophytes (6.4 percent), T.rubrum (6.2 percent), T tonsurans (4.5 percent), M.gypseum (3.9 percent), T.mentagrophytes var. interdigitale (0.4 percent) and E.floccosum (0.2 percent). Coincidently with previous studies accomplished in our province, tinea capitis is the prevailing affection while M.canis continues being its main and most frequent pathogenic agent (93.8 percent). The high number of M.canis isolations show clearly that zoophilic species are the most prevalent in our area. Children aged 0 to 3 year exhibited the highest prevalence followed by those of 4 to 6 year.

[A historical view of dermatomycology]. / Die Dermatomykologie im geschichtlichen Uberblick.

This historical review is focussed on clinical aspects of dermatomycology on one hand and on the discovery of fungi as pathogenic agents in dermatologic diseases on the other hand. This latter period in the 19th century established the beginning of dermatomycology. The basic role of fungus-host-interrelationship is mentioned with reference to earliest microscopical investigations of this issue on plants by Marcello Malphighi in the late 17th century.

Forty four years of dermatophytes in a Chicago clinic (1944-1988).

Data are presented on 39,270 cultures taken over a 44 year span (1944-1988) at the University of Chicago's Dermatology Clinic. In the mid 1940's Microsporum audouinii accounted for 60-80% of isolates. It gradually decreased over the next two decades and disappeared altogether in the 1970's. Trichophyton rubrum, rare in the 1940's accounted for over 60% of isolates in the mid-1960's only to be overtaken by T. tonsurans. This species, not isolated till the mid 1950's, became and remains the dominant dermatophyte at the present time. Both T. mentagrophytes and Epidermophyton floccosum increased in the 1970's and decreased later. Unusual circumstances resulted in clusters of T. verrucosum, T. terrestre, and T. schoenleinii isolates. Infections were associated with rural dairy workers, zoo handlers and immigrant families respectively. M. canis and M. gypseum were steady at a low rate throughout the entire period. Rare isolates included M. cookei, M. persicolor, M. racemosum, T. simii, T. soudanense, T. violaceum, and the soil keratinophile, Aphanoascus fulvescens.

Tokelau: contribuicao ao estudo de uma dermatomicose do indigenas do Brasil / Tokelau: contribution to the one study dermatomycose of the aboriginals of Brazil

"Tokelau" e uma molestia tropical, em que grandes areas do corpo sao cobertas com aneis concentricos e anulares, pardacentos com grande numero de escamas. O rosto e o couro cabeludo, de um modo geral, sao isentos. A mesma, e proveniente de um fungo vegetal, encontrado na epiderme, particularmente na camada cornea. O micelio e abundante, os esporos mais raros. Ele e formado por longos e finos filamentos bifurcados, juntos uns aos outros. Os esporos sao arredondados, altamente refrataveis, variando no tamanho. Para observa-los e aos esporos, as escamas epidermicas, sao raspadas com um objeto cortante e postas em uma lamina microscopica, com uma gota de potassa caustica (10 a 40 por cento). Uma laminula e aplicada com certa pressao para aplanar as escamas. O fungo e estudado melhor com uma lente de imersao, entretanto pode ser visto com lentes comuns a seco. O "tokelau" foi observado pela primeira vez por William Dampier no Arquipelago Malaio. Manson, em 1876, descreveu as principais caracteristicas da dermatose, considerando-a uma micose epidermica, designando-a pelo nome "Tinea imbricata". Roquette Pinto observou a existencia de Mal no Brasil conforme e relatado em seu livro "Rondonia", Estado do Mato Grosso. Isso foi confirmado por Olimpio da Fonseca e outros. A cultura desse fungo foi obtida por muitos autores, como por exemplo Langeron, Sabouraud, Olimpio da Fonseca, etc. Admite-se em geral que o fungo isolado das escamas e o "Trichophyton concentricum", Blanchard 1896. Vicente Grieco observou no Mato Grosso, Alto Xingu, 11 casos de "tokelau", que sao descritos no artigo junto

Epidemiología de las dermatofitosis animales / Epidemiology of animal dermatophytoses

Basándonos en los criterios ecológicos de Georg Otcenaseck & Rosicky, que permiten analizar las relaciones epidemiológicas entre los dermatofitos y sus hospedadores o habitat, se revisan las fuentes de infección y el modo de transmisión de las dermatofitosis, tanto en el hombre como en los animales, destacándose principalmente los casos en que éstos últimos son la fuente de infección

[Johann Lucas Schönlein (1793-1864), a researcher and clinician]. / Johann Lucas Schönlein (1793-1864), Forscher und Kliniker.

From 1833 to 1840, Johann Lucas Schönlein, a native of Bamberg, Germany, was Professor of Internal Medicine at the newly created University of Zurich, Switzerland. His career and professional personality are described succintly in this paper. Schönlein was a most successful clinical teacher. He was the first German professor to teach at Würzburg, 1819-1832) clinical percussion and auscultation. On the other hand, he obviously hated writing and publishing. His 3 important discoveries, all made during his years in Zurich, were published on a total of 3 printed pages: so-called typhoid crystals in patients' stools (1836), "peliosis rheumatica" (1837), and - most important - the causative agent of favus (1839), a fungus later named Achorion schoenleinii. This was the first instance of a human disease that could be clearly attributed to the action of a micro-organism.