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1.
PLoS One ; 18(2): e0276508, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36780451

RESUMEN

Leprosy, also known as Hansen's, is one of the listed neglected tropical diseases as a major health problem global. Treatment is one of the main alternatives, however, the scarcity of medication and its poor distribution are important factors that have driven the spread of the disease, leading to irreversible and multi-resistant complications. This paper uses a distribution methodology to optimize medication administration, taking into account the most relevant attributes for the epidemiological profile of patients and the deficit in treatment via Polychemotherapy. Multi-criteria Decision Methods were applied based on AHP-Electre model in a database with information from patients in the state of Para between 2015 and 2020. The results pointed out that 84% of individuals did not receive any treatment and, among these, the method obtained a gain in the distribution of 68% in patients with positive diagnosis for leprosy.


Asunto(s)
Lepra , Humanos , Preparaciones Farmacéuticas , Lepra/tratamiento farmacológico , Lepra/epidemiología , Lepra/diagnóstico , Quimioterapia Combinada , Manejo de Datos , Bases de Datos Factuales
2.
Front Microbiol ; 9: 2211, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30356683

RESUMEN

The fungal genus Fonsecaea comprises etiological agents of human chromoblastomycosis, a chronic implantation skin disease. The current hypothesis is that patients acquire the infection through an injury from plant material. The present study aimed to evaluate a model of infection in plant and animal hosts to understand the parameters of trans-kingdom pathogenicity. Clinical strains of causative agents of chromoblastomycosis (Fonsecaea pedrosoi and Fonsecaea monophora) were compared with a strain of Fonsecaea erecta isolated from a living plant. The clinical strains of F. monophora and F. pedrosoi remained concentrated near the epidermis, whereas F. erecta colonized deeper plant tissues, resembling an endophytic behavior. In an invertebrate infection model with larvae of a beetle, Tenebrio molitor, F. erecta exhibited the lowest survival rates. However, F. pedrosoi produced dark, spherical to ovoidal cells that resembled muriform cells, the invasive form of human chromoblastomycosis confirming the role of muriform cells as a pathogenic adaptation in animal tissues. An immunologic assay in BALB/c mice demonstrated the high virulence of saprobic species in animal models was subsequently controlled via host higher immune response.

3.
PLoS Negl Trop Dis ; 12(6): e0006532, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29953440

RESUMEN

Mycobacterium leprae (M. leprae) is a human pathogen and the causative agent for leprosy, a chronic disease characterized by lesions of the skin and peripheral nerve damage. Zoonotic transmission of M. leprae to humans by nine-banded armadillos (Dasypus novemcinctus) has been shown to occur in the southern United States, mainly in Texas, Louisiana, and Florida. Nine-banded armadillos are also common in South America, and residents living in some areas in Brazil hunt and kill armadillos as a dietary source of protein. This study examines the extent of M. leprae infection in wild armadillos and whether these New World mammals may be a natural reservoir for leprosy transmission in Brazil, similar to the situation in the southern states of the U.S. The presence of the M. leprae-specific repetitive sequence RLEP was detected by PCR amplification in purified DNA extracted from armadillo spleen and liver tissue samples. A positive RLEP signal was confirmed in 62% of the armadillos (10/16), indicating high rates of infection with M. leprae. Immunohistochemistry of sections of infected armadillo spleens revealed mycobacterial DNA and cell wall constituents in situ detected by SYBR Gold and auramine/rhodamine staining techniques, respectively. The M. leprae-specific antigen, phenolic glycolipid I (PGL-I) was detected in spleen sections using a rabbit polyclonal antibody specific for PGL-I. Anti-PGL-I titers were assessed by ELISA in sera from 146 inhabitants of Belterra, a hyperendemic city located in western Pará state in Brazil. A positive anti-PGL-I titer is a known biomarker for M. leprae infection in both humans and armadillos. Individuals who consumed armadillo meat most frequently (more than once per month) showed a significantly higher anti-PGL-I titer than those who did not eat or ate less frequently than once per month. Armadillos infected with M. leprae represent a potential environmental reservoir. Consequently, people who hunt, kill, or process or eat armadillo meat are at a higher risk for infection with M. leprae from these animals.


Asunto(s)
Antígenos Bacterianos/inmunología , Armadillos/microbiología , Reservorios de Enfermedades/microbiología , Glucolípidos/inmunología , Lepra/transmisión , Carne/microbiología , Mycobacterium leprae/aislamiento & purificación , Adulto , Animales , Antígenos Bacterianos/genética , Antígenos Bacterianos/aislamiento & purificación , Brasil/epidemiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Glucolípidos/genética , Glucolípidos/aislamiento & purificación , Humanos , Lepra/epidemiología , Lepra/microbiología , Masculino , Persona de Mediana Edad , Mycobacterium leprae/genética , Mycobacterium leprae/inmunología , Reacción en Cadena de la Polimerasa , Conejos , Riesgo , Bazo/microbiología , Adulto Joven , Zoonosis
4.
Nat Commun ; 9(1): 352, 2018 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-29367657

RESUMEN

Leprosy is a chronic human disease caused by the yet-uncultured pathogen Mycobacterium leprae. Although readily curable with multidrug therapy (MDT), over 200,000 new cases are still reported annually. Here, we obtain M. leprae genome sequences from DNA extracted directly from patients' skin biopsies using a customized protocol. Comparative and phylogenetic analysis of 154 genomes from 25 countries provides insight into evolution and antimicrobial resistance, uncovering lineages and phylogeographic trends, with the most ancestral strains linked to the Far East. In addition to known MDT-resistance mutations, we detect other mutations associated with antibiotic resistance, and retrace a potential stepwise emergence of extensive drug resistance in the pre-MDT era. Some of the previously undescribed mutations occur in genes that are apparently subject to positive selection, and two of these (ribD, fadD9) are restricted to drug-resistant strains. Finally, nonsense mutations in the nth excision repair gene are associated with greater sequence diversity and drug resistance.


Asunto(s)
Antiinfecciosos/farmacología , Farmacorresistencia Bacteriana/genética , Mycobacterium leprae/efectos de los fármacos , Filogenia , Codón sin Sentido , ADN Bacteriano/química , Genoma Bacteriano , Humanos , Pruebas de Sensibilidad Microbiana , Mycobacterium leprae/genética , Mycobacterium leprae/aislamiento & purificación
5.
PLoS Negl Trop Dis ; 10(11): e0005102, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27893750

RESUMEN

The human mutilating disease chromoblastomycosis is caused by melanized members of the order Chaetothyriales. To assess population diversity among 123 clinical strains of agents of the disease in Brazil we applied sequencing of the rDNA internal transcribed spacer region, and partial cell division cycle and ß-tubulin genes. Strains studied were limited to three clusters divided over the single family Herpotrichiellaceae known to comprise agents of the disease. A Fonsecaea cluster contained the most important agents, among which F. pedrosoi was prevalent with 80% of the total set of strains, followed by 13% for F. monophora, 3% for F. nubica, and a single isolate of F. pugnacius. Additional agents, among which two novel species, were located among members of the genus Rhinocladiella and Cyphellophora, with frequencies of 3% and 1%, respectively.


Asunto(s)
Ascomicetos/aislamiento & purificación , Cromoblastomicosis/microbiología , Ascomicetos/clasificación , Ascomicetos/genética , Brasil/epidemiología , Cromoblastomicosis/epidemiología , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Humanos , Epidemiología Molecular , Técnicas de Tipificación Micológica , Filogenia
6.
BMC Res Notes ; 4: 24, 2011 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-21276247

RESUMEN

BACKGROUND: Langerhans cells constitute a special subset of immature dendritic cells localized in the epidermis that play a key role in the skin's immune response. The production of cytokines is a key event in both the initiation and the regulation of immune responses, and different drugs can be used to remove or modify their production by DC and, therefore, alter immune responses in a broad spectrum of diseases, mainly in human inflammatory and autoimmune diseases. In the present study, we examined the effects of prednisone, thalidomide, cyclosporine A, and amitriptyline, drugs used in a variety of clinical conditions, on the production of TNF-α, IL-10, and IL-12 by purified epidermal Langerhans cells and peritoneal macrophages in BALB/c mice. FINDINGS: All drugs inhibited TNF-α production by Langerhans cells after 36 hours of treatment at two different concentrations, while prednisone and thalidomide decreased IL-12 secretion significantly, amitriptyline caused a less pronounced reduction and cyclosporine A had no effect. Additionally, TNF-α and IL-12 production by macrophages decreased, but IL-10 levels were unchanged after all treatments. CONCLUSIONS: Our results demonstrate that these drugs modulate the immune response by regulating pro-inflammatory cytokine production by purified epidermal Langerhans cells and peritoneal macrophages, indicating that these cells are important targets for immunosuppression in various clinical settings.

7.
J Cutan Pathol ; 36(2): 257-61, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18727664

RESUMEN

Chromoblastomycosis (CBM) is a difficult-to-treat dermal mycosis characterized by the presence of round, pigmented, sclerotic bodies formed by black fungi found in polymorphic lesions. According to the morphology of a lesion, different clinical types of the disease have been described. We present three patients who each developed a single, 10-cm diameter, 8 to 15-year-old, well-circumscribed, slow-growing, annular, papulosquamous or papulosquamous-verrucous lesion, with no regression despite the use of topical antifungals. Skin scrapings and biopsies confirmed CBM and microculture defined the agent as Fonsecaea pedrosoi. The patients were treated with 200 mg/day of itraconazole for 6-9 months and were discharged after complete regression of the lesions. All were examined after the first and second year of the end of treatment and there were no signs of recurrence. A new clinical type of CBM is described, and itraconazole appears to be effective and safe in curing these patients after no more than 9 months of therapy.


Asunto(s)
Antifúngicos/farmacología , Ascomicetos , Cromoblastomicosis , Itraconazol/farmacología , Hongos Mitospóricos , Administración Cutánea , Cromoblastomicosis/tratamiento farmacológico , Cromoblastomicosis/microbiología , Cromoblastomicosis/patología , Humanos , Masculino , Persona de Mediana Edad
8.
J Struct Biol ; 162(1): 75-84, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18096404

RESUMEN

Melanin is a complex polymer widely distributed in nature and has been described as an important virulence factor in pathogenic fungi. In the majority of fungi, the mechanism of melanin formation remains unclear. In Fonsecaea pedrosoi, the major etiologic agent of chromoblastomycosis, melanin is stored in intracellular vesicles, named melanosomes. This paper details the ultrastructural aspects of melanin formation, its storage and transportation to the cell wall in the human pathogenic fungus F. pedrosoi. In this fungus, melanin synthesis within melanosomes also begins with a fibrillar matrix formation, displaying morphological and structural features similar to melanosomes from amphibian and mammalian cells. Silver precipitation based on Fontana-Masson technique for melanin detection and immunocytochemistry showed that melanosome fuses with fungal cell membrane where the melanin is released and reaches the cell wall. Melanin deposition in the fungal cell wall occurs in concentric layers. Antibodies raised against F. pedrosoi melanin revealed the sites of melanin production and storage in the melanosomes. In addition, a preliminary description of the elemental composition of this organelle by X-ray microanalysis and elemental mapping revealed the presence of calcium, phosphorus and iron concentrated in its matrix, suggesting a new functional role for these organelles as iron storage compartments.


Asunto(s)
Ascomicetos/ultraestructura , Melanosomas/ultraestructura , Ascomicetos/metabolismo , Microanálisis por Sonda Electrónica , Humanos , Inmunohistoquímica , Melaninas/metabolismo , Melanosomas/metabolismo , Microscopía Electrónica de Transmisión , Micosis/microbiología
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