Sequela fibrótica na paracoccidioidomicose pulmonar: aspectos histopatológicos em camundongos BALB/c infectados com propágulos viáveis e não viáveis do Paracoccidioides brasiliensis

Patients with paracoccidioidomycosis often present pulmonary fibrosis and exhibit important respiratory limitations. Based on an already established animal model, the contribution of viable and non-viable P. brasiliensis propagules to the development of fibrosis was investigated. BALB/c male mice, 4-6 weeks old were inoculated intranasally either with 4x10(6 )viable conidia (Group I), or 6.5x10(6) fragmented yeast cells (Group II). Control animals received PBS. Six mice per period were sacrificed at 24, 48, 72h (initial) and 1, 2, 4, 8, 12 and 16 weeks post-challenge (late). Paraffin embedded lungs were sectioned and stained with H&E, trichromic (Masson), reticulin and Grocott´s. During the initial period PMNs influx was important in both groups and acute inflammation involving 34% to 45% of the lungs was noticed. Later on, mononuclear cells predominated. In group I, the inflammation progressed and granulomas were formed and by the 12th week they fussed and became loose. Thick collagen I fibers were observed in 66.6% and 83.3% of the animals at 8 and 12 weeks, respectively. Collagen III, thick fibers became apparent in some animals at 4weeks and by 12 weeks, 83% of them exhibited alterations in the organization and thickness of these elements. In group II mice, this pattern was different with stepwise decrease in the number of inflammatory foci and lack of granulomas. Although initially most animals in this group had minor alterations in thin collagen I fibers, they disappeared by the 4th week. Results indicate that tissue response to fragmented yeast cells was transitory while viable conidia evoked a progressive inflammatory reaction leading to granuloma formation and to excess production and/or disarrangement of collagens I and III; the latter led to fibrosis.Pacientes com paracoccidioidomicose apresentam, algumas vezes, fibrose pulmonar e exibem limitações respiratórias importantes. Baseados num modelo animal já estabelecido da micose, estudamos a possível contribuição de propágulos viáveis e não viáveis do Paracoccidioides brasiliensis ao desenvolvimento da fibrose. Assim, camundongos BALB/c, machos de 4 a 6 semanas de idade, foram inoculados intranasalmente com 4 x 10(6) conídios viáveis (Grupo I), ou com 6,5 x 10(6) fragmentos não viáveis de células leveduriformes (Grupo II). Animais controles (Grupo III) receberam unicamente PBS. Seis camundongos por período foram sacrificados 24, 48, 72h (inicial) e 1, 2, 4, 8, 12 e 16 semanas pós-inoculação (tardio). Os pulmões dos animais foram fixados, incluidos em parafina, cortados e corados com H & E, Tricrômico (Masson), reticulina e Grocott. Durante o período inicial houve afluxo importante de PMNs em ambos os grupos I e II, e a inflamação aguda comprometeu entre 34 a 45% dos pulmões. Depois, foram as células mononucleares as que predominaram. No grupo I, a inflamação progrediu e formaram-se granulomas os quais, às 12 semanas, ficaram confluentes e frouxos. Adicionalmente, se observaram fibras de colágeno tipo I muito densas em 66,6% e 83,3% dos animais após 8 e 12 semanas, respectivamente. As fibras do colágeno tipo III foram observadas nos animais a partir das 4 semanas pós-infecção, e 83% deles exibiram, às 12 semanas, alterações na sua distribuição e organização. Nos animais do grupo II o padrão foi diferente, pois mostraram diminuição gradual no número de focos inflamatórios e não houve formação dos granulomas. Embora animais deste grupo tivessem no período inicial pequenas alterações nas fibras de colágeno tipo I, estas desapareceram por volta da 4a semana. Os resultados indicam que a resposta tissular aos fragmentos de leveduras foi transitória, enquanto que os conídios induzem resposta inflamatória progressiva permitindo a formação de granuloma e um excesso na produção e desorganização dos colágenos I e III, permitindo finalmente a fibrose

Volcanic Emissions and Atmospheric Pollution: A Study of Nanoparticles

The influence of emissions of an active volcano on the composition of nanoparticles and ultrafine road dust was identified in an urban area of the Andes. Although many cities are close to active volcanoes, few studies have evaluated their influence in road dust composition. Air quality in urban areas is significantly affected by non-exhaust emissions (e.g. road dust, brake wear, tire wear), however, natural sources such as volcanoes also impact the chemical composition of the particles. In this study, elements from volcanic emissions such as Si \u3e Al \u3e Fe \u3e Ca \u3e K \u3e Mg, and Si—Al with K were identified as complex hydrates. Similarly, As, Hg, Cd, Pb, As, H, Cd, Pb, V, and salammoniac were observed in nanoparticles and ultrafine material. Mineral composition was detected in the order of quartz\u3e mullite\u3e calcite\u3e kaolinite\u3e illite\u3e goethite\u3e magnetite\u3e zircon\u3e monazite, in addition to salammoniac, a tracer of volcanic sources. The foregoing analysis reflects the importance of carrying out more studies relating the influence of volcanic emissions in road dust in order to protect human health. The road dust load (RD10) ranged between 0.8 and 26.8 mg m−2 in the city

Volcanic emissions and atmospheric pollution: a study of nanoparticles

The influence of emissions of an active volcano on the composition of nanoparticles and ultrafine road dust was identified in an urban area of the Andes. Although many cities are close to active volcanoes, few studies have evaluated their influence in road dust composition. Air quality in urban areas is significantly affected by non-exhaust emissions (e.g. road dust, brake wear, tire wear), however, natural sources such as volcanoes also impact the chemical composition of the particles. In this study, elements from volcanic emissions such as Si > Al > Fe > Ca > K > Mg, and Si Al with K were identified as complex hydrates. Similarly, As, Hg, Cd, Pb, As, H, Cd, Pb, V, and salammoniac were observed in nanoparticles and ultrafine material. Mineral composition was detected in the order of quartz> mullite> calcite> kaolinite> illite> goethite> magnetite> zircon> monazite, in addition to salammoniac, a tracer of volcanic sources. The foregoing analysis reflects the importance of carrying out more studies relating the influence of volcanic emissions in road dust in order to protect human health. The road dust load (RD10) ranged between 0.8 and 26.8 mg m−2 in the city

Identificación de algunos genes asociados al proceso de germinación de la conidia al micelio en Paracoccidioides brasiliensis

Introduction. Paracoccidioides brasiliensis is a thermo-dimorphic fungus. At room temperature it grows as a mold that produces conidia, whereas in the vertebrate host it grows as a multiple-budding yeast. The molecular mechanisms involved in the germination from the conidia to the mycelia process remain unknown.Objective. The kinetics of conidia to mycelia germination process were studied in the dimorphic fungus P. brasiliensis. Gene expression during this process was evaluated by construction and analysis of an EST library.Materials and methods. For the germination kinetics study, P. brasiliensis conidia were isolated as single cell units. Then, they were cultured at 18° C in BHI (brain-heart infusion) broth for 24, 48, 72 and 96 hr. After each perion, they were examined by light microscopy. From conidia harvested at 96 hr, an EST library was constructed; at this stage the gene expression was presumed to be maximal for the germination process.Results. During the conidia to the mycelia developmental process, the following germination rates were observed: at 24 hr, 11.7±1.2%; at 48 hr, 30±0.6%; at 72 hr, 43±1.3%; and at 96 hr, 66±2.4%. At the 96 hour stage, an EST library was constructed. It consisted of 129 sequences grouped in 4 contigs and 7 singlets for a total of 11 possible genes. Eight of the sequences had not been described previously in other EST libraries of this fungus.Conclusions. New genes were identified that were expressed during the conidia to the mycelia germination process and may represent genes specific to the germination process.Introducción. Paracoccidioides brasiliensis es un hongo dimórfico térmico, que a temperatura ambiente se presenta como un moho productor de conidias, mientras que en el huésped se comporta como una levadura de gemación múltiple. Los mecanismos moleculares que rigen la germinación de conidia a micelio aún se desconocen.Objetivo. Estudiar en P. brasiliensis la cinética del proceso de germinación de conidia a micelio y determinar los genes expresados durante este proceso mediante la construcción y el análisis de una librería EST (Expressed Sequence Tag).Materiales y métodos. Para el estudio de la cinética de germinación, se produjeron y aislaron conidias de P. brasiliensis. Estas fueron incubadas en cultivos líquidos a 18°C por 24, 48, 72 y 96 horas, y se examinaron por microscopía de luz. A partir de conidias cultivadas por 96 horas, se construyó y caracterizó una librería EST, la cual representaría los genes expresados durante el proceso de germinación.Resultados. Durante el proceso de germinación de conidia a micelio, se observó 11,7±1,2%, 30±0,6%, 43±1,3% y 66±2,4% de germinación a las 24, 48, 72 y 96 horas de incubación, respectivamente. Además, se obtuvo una librería del proceso de germinación consistente en 129 secuencias agrupadas en cuatro secuencias contiguas y siete secuencias únicas, para un total de 11 posibles genes. Ocho secuencias (72,7%) no habían sido descritas anteriormente en otras librerías informadas para este hongo y podrían representar genes específicos de la germinación de conidia a micelio.Conclusiones. Éste es el primer reporte en el que se identifican genes no descritos anteriormente, que son expresados durante la germinación de conidia a micelio, proceso de gran importancia en la biología de P. brasiliensis

Virus del papiloma humano, respuesta inmune y cáncer cervical: una relación compleja Human papillomavirus, immune response and cervical cancer: a complex relationship

El cáncer de cuello uterino se considera como un grave problema de salud pública con una alta incidencia en los países en desarrollo. La infección, permanencia y replicación del virus de papiloma humano (HPV, por sus siglas en inglés) de alto riesgo a nivel cervical están relacionadas con el desarrollo del cáncer de cuello uterino. En condiciones normales, el sistema inmune es capaz de controlar y eliminar la infección por acción de la inmunidad innata, la activación de una respuesta tipo celular y la creación de anticuerpos dirigidos principalmente a las proteínas de la cápside del virión (L1 y L2). A pesar de toda la maquinaria de protección inmune del hospedero, el virus posee estrategias de evasión, conservando un número reducido de copias en las células basales proliferantes y aprovechando la corta vida natural del queratinocito. En esta revisión se tratarán los diferentes mecanismos inmunológicos del hospedero en la respuesta a la infección por el HPV.Cervical cancer is considered to be a serious public health problem having a high incidence in developing countries. High-risk cervical human papillomavirus (HPV) infection, permanence and replication are closely related to the development of cervical cancer. The immune system is able to control and clear such infection in normal conditions by innate immunity action, activating a cellular response and creating antibodies, mainly directed against virion capsid proteins (L1 and L2). In spite of the host’s entire immune protection machinery, the virus can take evasion strategies, maintaining a reduced number of copies in proliferating base cells and taking advantage of the keratinocyte’s short natural life. This review attempts to show the host’s different immunological mechanisms elicited in response to HPV infection

Encefalitis herpética confirmada por reacción en cadena de la polimerasa en tiempo real: reporte de caso Herpetic encephalitis confirmed by real time polymerase chain reaction: case report

La encefalitis herpética es una enfermedad grave asociada al virus herpes simple 1 ó 2, con una alta letalidad, incidencia de complicaciones y secuelas neurológicas permanentes. Aparece en forma endémica y en pacientes inmunocompetentes. Puede manifestarse como un cuadro clásico de encefalitis infecciosa con fiebre, cefalea y alteración en el nivel de conciencia. Debido al compromiso del lóbulo temporal las manifestaciones clínicas pueden incluir también alucinaciones, afasia y cambios de personalidad. Las secuelas en los pacientes tratados son significativas. Objetivo: mostrar la importancia de la utilización del diagnóstico molecular temprano en pacientes con sospecha de encefalitis herpética. Métodos: el diagnóstico de la encefalitis herpética ha cambiado en los últimos años gracias al advenimiento de la reacción en cadena de la polimerasa en tiempo real en líquido cefalorraquídeo para Herpes virus simple, una estrategia rápida y de alta sensibilidad y especificidad, que en nuestro medio ha permitido reemplazar los diagnósticos presuntivos realizados por tomografía axial computarizada o electroencefalograma o los bajos rendimientos del aislamiento viral en el líquido cefaloraquídeo. Resultados: se describe el caso clínico de un paciente con encefalitis herpética asistido en nuestro hospital, con diagnóstico confirmado por reacción en cadena de la polimerasa en tiempo real, presentando estudios imaginológicos y neuropsicológicos compatibles con el diagnóstico. Conclusiones: los resultados de laboratorio y el diagnóstico temprano son críticos para el tratamiento precoz y la evolución del paciente. The herpetic encephalitis is a serious disease associated to the herpes virus simplex 1 or 2 with high mortality, permanent incidence of complications and neurological sequels. It appears in endemic form and in immunocompetent patients. It can be shown like a classical manifest of infectious encephalitis, with fever, migraine and alteration in the conscience level. Due to the commitment of the temporary lobe, the clinical manifestations can also include hallucinations, aphasia and changes of personality. The sequels in the treated patients are significant. Objective: to show the importance of early molecular diagnosis in patients with suspected herpetic encephalitis infection. Methods: the diagnosis of the herpetic encephalitis has changed in the last years thanks to the coming of the real time polymerase chain reaction for herpes simplex virus in cerebrospinal fluid, a fast strategy with high sensitivity and specificity that has allowed to replace the suspect diagnoses made by tomography axial computerized or electroencephalogram, or the low yields of the viral isolation in the cerebrospinal fluid. Results: A clinical case report of a patient attended in our hospital with image and neuropsychological studies compatible for herpetic encephalitis, and confirmed diagnosis by real time polymerase chain reaction is described. Conclusions: the results of laboratory and the early diagnosis are critical for the precocious treatment and the evolution of the patient

Rojas Immunology

Es la acción conjunta de células y moléculas que nos defienden de las agresiones externas por agentes infecciosos y de las agresiones internas producidas por infecciones virales y por alteraciones celulares ocasionadas por el desarrollo de afecciones autoinmunes o por tumores malignos.Origen de macrófagos tisulares.Linfocitos de la inmunidad innata.Actualización de las citoquinas.Actualización de la respuesta inmune a todos los procesos infecciosos.Actualización de todo lo relacionado con las enfermedades autoinmunes

Comparison of Top-Down and Bottom-Up Road Transport Emissions through High-Resolution Air Quality Modeling in a City of Complex Orography

Vehicular emissions are a predominant source of pollution in urban environments. However, inherent complexities of vehicular behavior are sources of uncertainties in emission inventories (EIs). We compare bottom-up and top-down approaches for estimating road transport EIs in Manizales, Colombia. The EIs were estimated using a COPERT model, and results from both approaches were also compared with the official top-down EI (estimated from IVE methodology). The transportation model PTV-VISUM was used for obtaining specific activity information (traffic volumes, vehicular speed) in bottom-up estimation. Results from COPERT showed lower emissions from the top-down approach than from the bottom-up approach, mainly for NMVOC (−28%), PM10 (−26%), and CO (−23%). Comparisons showed that COPERT estimated lower emissions than IVE, with higher differences than 40% for species such as PM10, NOX, and CH4. Furthermore, the WRF–Chem model was used to test the sensitivity of CO, O3, PM10, and PM2.5 predictions to the different EIs evaluated. All studied pollutants exhibited a strong sensitivity to the emission factors implemented in EIs. The COPERT/top-down was the EI that produced more significant errors. This work shows the importance of performing bottom-up EI to reduce the uncertainty regarding top-down activity data