Corporacion para Investigaciones Biologicas

Medellín, Colombia

Corporacion para Investigaciones Biologicas

Medellín, Colombia
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Queiroz-Telles F.,Federal University of Paraná | Nucci M.,Federal University of Rio de Janeiro | Tobon A.,Corporacion Para Investigaciones Biologicas | Restrepo A.,Corporacion Para Investigaciones Biologicas
Medical Mycology | Year: 2011

Implantation or subcutaneous mycoses are a frequent health problem in Latin American countries and other tropical and subtropical areas. Although such infections rarely cause disseminated or invasive disease, they have an important impact on public health, and timely diagnosis and appropriate treatment remain important. Although some implantation mycoses are found in immunocompromised persons, the immunocompetent population is the principal target in Latin America. Most etiologic agents are found in soil, vegetation, and decaying matter in tropical, subtropical, and humid environments and infection is commonly the result of penetrating injury. Infections primarily occur (1) among low socioeconomic groups, (2) among those living in rural areas or involved in farming, hunting, or other outdoor activities, and (3) particularly among adult men. This review focuses on the epidemiology of the most clinically significant implantation mycoses in Latin America, i.e., sporotrichosis, eumycetoma, chromoblastomycosis, subcutaneous phaeohyphomycosis, subcutaneous zygomycosis, and lacaziosis. Main epidemiologic findings, clinical manifestations, diagnosis, and treatment options are also discussed. © 2011 ISHAM.

Hernandez O.,University of Antioquia | Hernandez O.,Major College of Antioquia | Garcia A.M.,Corporacion para Investigaciones Biologicas | Almeida A.J.,University of Minho | And 6 more authors.
Yeast | Year: 2011

This study focuses on gene expression during crucial biological phenomena of the dimorphic fungal human pathogen Paracoccidioides brasiliensis, the conidia-to-yeast (C-Y) transition and the conidia-to-mycelia (C-M) germination. We studied 10 genes involved in different cellular functions: oxidative stress response (alternative oxidase (AOX), superoxide dismutase (SOD), flavodoxin, conserved hypothetical protein (Y20)); cell metabolism (glyceraldehyde-3-phosphate dehydrogenase (GADPH), cholestenol Delta-isomerase (ChDI), glycine dehydrogenase (GDh)) and heat shock response (Heat shock protein 90 (HSP90)), and cell synthesis and wall structure (glucan synthase-1 (GS-1), α-1,3-glucan synthase (αGS), and mannosyltransferase (MT)). Gene expression was measured during the first 72h and 96h of C-Y and C-M, respectively, previously shown to be a fundamental time frame for the consolidation of these cellular processes. The gene expression of AOX, GAPDH, HSP90, MT, αGS, and GDh was significantly increased during the C-Y transition, while SOD, ChDI, GAPDH, MT, GDh, and GS-1 were increased during C-M germination. Additionally, some were highly expressed in each process: AOX, HSP90, and αGS during C-Y; SOD, ChDI, and GS-1 during C-M. Altogether, these data add new information regarding gene expression during the C-Y and C-M processes. Future research will be targeted to further characterize the true relevance of the studied genes during the morphological transition, either during adaptation to the environment or to the infected host. © 2011 John Wiley & Sons, Ltd.

Escandon P.,Instituto Nacional Of Salud | de Bedout C.,Corporacion para Investigaciones Biologicas | Lizarazo J.,Hospital Universitario Erasmo Meoz | Agudelo C.I.,Instituto Nacional Of Salud | And 4 more authors.
Biomedica | Year: 2012

Introduction: A survey on cryptococcosis is being conducted regularly in Colombia since 1997. We present hereby the results corresponding to patients diagnosed from 2006 to 2010. Objective: To analyze the data obtained during this period. Materials and methods: Retrospective analysis of the corresponding surveys. Results: A total of 526 surveys originating from 72% of the Colombian political divisions were received during the 5-year period. Most patients (76.6%) were males and 74.9% were 21-50 years old. The most prevalent risk factor was HIV infection (83.5%) with cryptococcosis defining AIDS in 23% of the cases. In the general population the estimated mean annual incidence rate for cryptococcosis was 2.4×106 inhabitants while in AIDS patients this rate rose to 3.3×103. In 474 surveys stating clinical features, most frequent complaints were headache 84.5%, fever 63.4%, nausea and vomiting 57.5%, mental alterations 46.3%, meningeal signs 33.0%, cough 26.4% and visual alterations 24.5%. Neurocryptococcosis was recorded in 81.8% of the cases. Laboratory diagnosis was based on direct examination, culture and latex in 29.3% cases. From 413 Cryptococcus isolates analyzed, 95.6% were identified as C. neoformans var. grubii, 1% C. neoformans var. neoformans, and 3.4% C. gattii. Treatment was reported for 71.6% of the cases with amphotericin B alone or in combination with fluconazole prescribed in 28%. Conclusions: Surveys done through passive surveillance continue to be sentinel markers for HIV infection and represent a systematic approach to the study of opportunistic problems regularly afflicting AIDS patients since cryptococcosis requires no compulsory notification in Colombia.

PubMed | Corporacion para Investigaciones Biologicas, University of Medellín and University of Antioquia
Type: Journal Article | Journal: The Brazilian journal of infectious diseases : an official publication of the Brazilian Society of Infectious Diseases | Year: 2015

Paracoccidioidomycosis is a systemic and endemic mycosis, restricted to tropical and subtropical areas of Latin America. The infection is caused by the thermal dimorphic fungus Paracoccidioides brasiliensis and Paracoccidioides lutzii. The diagnosis of paracoccidioidomycosis is usually performed by microscopic examination, culture and immunodiagnostic tests to respiratory specimens, body fluids and/or biopsies; however these methods require laboratory personnel with experience and several days to produce a result. In the present study, we have validated and evaluated a nested PCR assay targeting the gene encoding the Paracoccidioides gp43 membrane protein in 191 clinical samples: 115 samples from patients with proven infections other than paracoccidioidomycosis, 51 samples as negative controls, and 25 samples from patients diagnosed with paracoccidioidomycosis. Additionally, the specificity of the nested PCR assay was also evaluated using purified DNA isolated from cultures of different microorganisms (n=35) previously identified by culture and/or sequencing. The results showed that in our hands, this nested PCR assay for gp43 protein showed specificity and sensitivity rates of 100%. The optimized nested PCR conditions in our laboratory allowed detection down to 1fg of P. brasiliensis DNA.

PubMed | Institute Pasteur Of La Guadeloupe, Industrial University of Santander, Corporacion para Investigaciones Biologicas, University of Cauca and 4 more.
Type: Journal Article | Journal: PloS one | Year: 2014

Phylogeographic composition of M. tuberculosis populations reveals associations between lineages and human populations that might have implications for the development of strategies to control the disease. In Latin America, lineage 4 or the Euro-American, is predominant with considerable variations among and within countries. In Colombia, although few studies from specific localities have revealed differences in M. tuberculosis populations, there are still areas of the country where this information is lacking, as is a comparison of Colombian isolates with those from the rest of the world.A total of 414 M. tuberculosis isolates from adult pulmonary tuberculosis cases from three Colombian states were studied. Isolates were genotyped using IS6110-restriction fragment length polymorphism (RFLP), spoligotyping, and 24-locus Mycobacterial interspersed repetitive units variable number tandem repeats (MIRU-VNTRs). SIT42 (LAM9) and SIT62 (H1) represented 53.3% of isolates, followed by 8.21% SIT50 (H3), 5.07% SIT53 (T1), and 3.14% SIT727 (H1). Composite spoligotyping and 24-locus MIRU- VNTR minimum spanning tree analysis suggest a recent expansion of SIT42 and SIT62 evolved originally from SIT53 (T1). The proportion of Haarlem sublineage (44.3%) was significantly higher than that in neighboring countries. Associations were found between M. tuberculosis MDR and SIT45 (H1), as well as HIV-positive serology with SIT727 (H1) and SIT53 (T1).This study showed the population structure of M. tuberculosis in several regions from Colombia with a dominance of the LAM and Haarlem sublineages, particularly in two major urban settings (Medelln and Cali). Dominant spoligotypes were LAM9 (SIT 42) and Haarlem (SIT62). The proportion of the Haarlem sublineage was higher in Colombia compared to that in neighboring countries, suggesting particular conditions of co-evolution with the corresponding human population that favor the success of this sublineage.

Colombo A.L.,Federal University of São Paulo | Tobn A.,Corporacion Para Investigaciones Biologicas | Restrepo A.,Corporacion Para Investigaciones Biologicas | Queiroz-Telles F.,Federal University of Paraná | Nucci M.,Federal University of Rio de Janeiro
Medical Mycology | Year: 2011

Although endemic mycoses are a frequent health problem in Latin American countries, clinical and epidemiological data remain scarce and fragmentary. These mycoses have a significant impact on public health, and early diagnosis and appropriate treatment remain important. The target population for endemic disease in Latin America is mostly represented by low-income rural workers with limited access to a public or private health system. Unfortunately, diagnostic tools are not widely available in medical centers in Latin America; consequently, by the time patients are diagnosed with fungal infection, many are already severely ill. Among immunocompromised patients, endemic mycoses usually behave as opportunistic infections causing disseminated rather than localized disease. This paper reviews the epidemiology of the most clinically significant endemic mycoses in Latin America: paracoccidioidomycosis, histoplasmosis, and coccidioidomycosis. The burdens of disease, typically affected populations, and clinical outcomes also are discussed. © 2011 ISHAM.

Velez J.M.,National University of Colombia | Pineda R.,Corporacion para Investigaciones Biologicas | Galindo L.,Corporacion para Investigaciones Biologicas | Arango R.,National University of Colombia | Morales J.G.,National University of Colombia
Genetic Resources and Crop Evolution | Year: 2016

Potatoes are grown as a staple food in a number of countries around the world. Potatoes production is fourth at the worldwide level and provides carbohydrates and other nutrients in several developing countries. In South America a large diversity of wild and cultivated potato genotypes have been identified, from which several species have been described in Colombia. The last known collections of wild potato germplasm in Colombia were performed up to 1992, and we know little of wild potato distribution since that time. Several factors may threaten these populations, and we performed field surveys of the Colombian populations, as well as a literature review, studies of herbarium specimens from eight Colombian herbaria and databases from reference collections available on the internet. Based in these data we performed field trips in several Colombian regions where wild and cultivated species were reported previously. We identified Solanum andreanum Baker, S. colombianum Dunal and S. flahaultii Bitter, populations according to the taxonomic concepts of Spooner and Fajardo; or S. andreanum, S. colombianum, S. flahaultii, S. moscopanum Hawkes and S. tuquerrense Hawkes, according to the taxonomy of Hawkes. We observed habitat loss or disturbance that may partially explain the apparent decrease or eventual disappearance of some species at specific sites. © 2015, Springer Science+Business Media Dordrecht.

Tobon A.M.,Corporacion para Investigaciones Biologicas | Agudelo C.A.,Corporacion para Investigaciones Biologicas | Restrepo C.A.,Pontifical Bolivarian University | Villa C.A.,Pontifical Bolivarian University | And 3 more authors.
American Journal of Tropical Medicine and Hygiene | Year: 2010

This study assessed adrenal function in patients with paracoccididioidomycosis who had been treated to determine a possible connection between high antibody titers and adrenal dysfunction attributable to persistence of the fungus in adrenal gland. Adrenal gland function was studied in 28 previously treated patients, 2 (7.1%) of whom were shown to have adrenal insufficiency and 7 (259%) who showed a below normal response to stimuli by adrenocorticotropic hormone. Paracoccidioides brasiliensis was detected in the adrenal gland from one of the patients with adrenal insufficiency. Although the study failed to demonstrate a significant difference between high antibody titers and low cortisol levels, the proportion of adrenal insufficiency detected and the subnormal response to adrenocorticotropic hormone confirmed that adrenal damage is an important sequela of paracoccidioidomycosis. Studies with a larger number of patients should be conducted to confirm the hypothesis of persistence of P. brasiliensis in adrenal gland after therapy. Copyright © 2010 by The American Society of Tropical Medicine and Hygiene.

Shankar J.,California Institute for Medical Research | Shankar J.,Santa Clara Valley Medical Center | Shankar J.,Stanford University | Restrepo A.,Corporacion para Investigaciones Biologicas | And 6 more authors.
Clinical Microbiology Reviews | Year: 2011

Paracoccidioidomycosis, one of the most important endemic and systemic mycoses in Latin America, presents several clinical pictures. Epidemiological studies indicate a striking rarity of disease (but not infection) in females, but only during the reproductive years. This suggested a hormonal interaction between female hormones and the etiologic dimorphic fungus Paracoccidioides brasiliensis. Many fungi have been shown to use hormonal (pheromonal) fungal molecules for intercellular communication, and there are increasing numbers of examples of interactions between mammalian hormones and fungi, including the specific binding of mammalian hormones by fungal proteins, and suggestions of mammalian hormonal modulation of fungal behavior. This suggests an evolutionary conservation of hormonal receptor systems. We recount studies showing the specific hormonal binding of mammalian estrogen to proteins in P. brasiliensis and an action of estrogen to specifically block the transition from the saprophytic form to the invasive form of the fungus in vitro. This block has been demonstrated to occur in vivo in animal studies. These unique observations are consistent with an estrogen-fungus receptor-mediated effect on pathogenesis. The fungal genes responsive to estrogen action are under study. © 2011, American Society for Microbiology. All Rights Reserved.

PubMed | Corporacion para Investigaciones Biologicas and University of Antioquia
Type: | Journal: Revista do Instituto de Medicina Tropical de Sao Paulo | Year: 2015

Research on Paracoccidioides brasiliensis has centered in the yeast cell probably because of the lack of distinctive features in the mycelium. In 1942 and for the first time, lateral conidia were noticed in the fungus hyphae. Later on, Brazilian, Venezuelan and Argentinean researchers described aleurias when the fungus was grown in natural substrates. In 1970 authors became interested in the conidia and were able to obtain them in large numbers and treat them as individual units. Their shape and size were defined and the presence of all the elements of a competent eukaryotic cell were demonstrated. Conidia exhibited thermal dimorphism and, additionally, when given intranasally to BALB/c male mice, they converted into yeasts in the lungs and produce progressive pulmonary lesions with further dissemination to other organs. Studies on the phagocyte-conidia interaction were revealing and showed that these versatile structures allow a better understanding of the host- P. brasiliensis interactions.

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