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Several disturbances in T-cell mediated immunity have been described during aging, but immunosenescence of the B-cell compartment is less well elucidated. The peripheral blood B-cell compartment (CD19+) can be split into six main subpopulations according to the cell surface markers IgD, CD27, CD24, and CD38: Transitional, naïve, unswitched, switched, double negative and plasmablasts. We thus aimed to verify whether shifts in these subsets occur during healthy and pathological aging. We recruited three groups of aged people (> 60 years old), healthy, COPD patients, and smokers without altered pulmonary function test, and a fourth group of individuals 18-40 years old (youngs). Total B-cells percentage and absolute number were similar among the healthy aged, COPD patients, and youngs, but the smokers showed significantly higher absolute numbers. While all six B-cell subset percentages were comparable among the healthy aged, COPD patients, and youngs, smokers showed significantly higher percentages of switched B-cells and reduced naïve B-cells than the other three groups, resulting in an inverted naive:switched ratio. Analysis of the cell subset absolute numbers showed a similar trend. Overall, our results suggest that aging drives milder alterations in the distribution of peripheral blood B-cell subpopulations than in the T-cell compartment. We suggest that it is the T-cell immunosenescence that most contributes to the poor humoral immune responses in the elderly, vaccine responses included. Surprisingly it was the smokers who showed significant alterations when compared with the youngs, healthy aged, and aged COPD patients, probably as a result of the chronic immune stimulation described in active smoking subjects.
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Subgrupos de Linfocitos B , Enfermedad Pulmonar Obstructiva Crónica , Anciano , Humanos , Linfocitos B , Envejecimiento , Subgrupos de Linfocitos B/química , Antígenos CD19/análisisRESUMEN
We assessed predictive models (PMs) for diagnosing Pneumocystis jirovecii pneumonia (PCP) in AIDS patients seen in the emergency room (ER), aiming to guide empirical treatment decisions. Data from suspected PCP cases among AIDS patients were gathered prospectively at a reference hospital's ER, with diagnoses later confirmed through sputum PCR analysis. We compared clinical, laboratory, and radiological data between PCP and non-PCP groups, using the Boruta algorithm to confirm significant differences. We evaluated ten PMs tailored for various ERs resource levels to diagnose PCP. Four scenarios were created, two based on X-ray findings (diffuse interstitial infiltrate) and two on CT scans ("ground-glass"), incorporating mandatory variables: lactate dehydrogenase, O2sat, C-reactive protein, respiratory rate (> 24 bpm), and dry cough. We also assessed HIV viral load and CD4 cell count. Among the 86 patients in the study, each model considered either 6 or 8 parameters, depending on the scenario. Many models performed well, with accuracy, precision, recall, and AUC scores > 0.8. Notably, nearest neighbor and naïve Bayes excelled (scores > 0.9) in specific scenarios. Surprisingly, HIV viral load and CD4 cell count did not improve model performance. In conclusion, ER-based PMs using readily available data can significantly aid PCP treatment decisions in AIDS patients.
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Servicio de Urgencia en Hospital , Pneumocystis carinii , Neumonía por Pneumocystis , Humanos , Neumonía por Pneumocystis/diagnóstico , Neumonía por Pneumocystis/diagnóstico por imagen , Masculino , Pneumocystis carinii/aislamiento & purificación , Femenino , Adulto , Persona de Mediana Edad , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Carga ViralRESUMEN
Coccidioidomycosis, listed as a priority mycosis by the WHO, is endemic in the United States but often overlooked in Central and South America. Employing a multi-institutional approach, we investigate how disease characteristics, pathogen genetic variation, and environmental factors impact coccidioidomycosis epidemiology and outcomes in South America. We identified 292 cases (1978-2021) and 42 outbreaks in Piauí and Maranhão states, Brazil, the largest series outside the US/Mexico epidemic zone. The male-to-female ratio was 57.4:1 and the most common activity was armadillo hunting (91.1%) 4 to 30 days before symptom onset. Most patients (92.8%) exhibited typical acute pulmonary disease, with cough (93%), fever (90%), and chest pain (77%) as predominant symptoms. The case fatality rate was 8%. Our negative binomial regression model indicates that reduced precipitation levels in the current (p = 0.015) and preceding year (p = 0.001) predict heightened incidence. Unlike other hotspots, acidic soil characterizes this region. Brazilian strains differ genomically from other C. posadasii lineages. Northeastern Brazil presents a distinctive coccidioidomycosis profile, with armadillo hunters facing elevated risks. Low annual rainfall emerges as a key factor in increasing cases. A unique C. posadasii lineage in Brazil suggests potential differences in environmental, virulence, and/or pathogenesis traits compared to other Coccidioides genotypes.
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Coccidioidomicosis , Humanos , Femenino , Masculino , Animales , Brasil/epidemiología , Coccidioidomicosis/epidemiología , Armadillos , Genómica , GenotipoRESUMEN
ABSTRACT Paracoccidioidomycosis (PCM) is a systemic fungal infection caused by Paracoccidioides spp. It can occur as an acute/subacute form (A/SAF), a chronic form (CF) and rarely as a mixed form combining the features of the two aforementioned forms in an immunocompromised patient. Here, we report a 56-year-old male patient with CF-PCM who presented with atypical manifestations, including the development of an initial esophageal ulcer, followed by central nervous system (CNS) lesions and cervical and abdominal lymphatic involvement concomitant with severe SARS-CoV-2 infection. He was HIV-negative and had no other signs of previous immunodeficiency. Biopsy of the ulcer confirmed its mycotic etiology. He was hospitalized for treatment of COVID-19 and required supplemental oxygen in the intensive unit. The patient recovered without the need for invasive ventilatory support. Investigation of the extent of disease during hospitalization revealed severe lymphatic involvement typical of A/SAF, although the patient`s long history of high-risk exposure to PCM, and lung involvement typical of the CF. Esophageal involvement is rare in non-immunosuppressed PCM patients. CNS involvement is also rare. We suggest that the immunological imbalance caused by the severe COVID-19 infection may have contributed to the patient developing atypical severe CF, which resembles the PCM mixed form of immunosuppressed patients. Severe COVID-19 infection is known to impair the cell-mediated immune response, including the antiviral response, through T-lymphopenia, decreased NK cell counts and T-cell exhaustion. We hypothesize that these alterations would also impair antifungal defenses. Our case highlights the potential influence of COVID-19 on the course of PCM. Fortunately, the patient was timely treated for both diseases, evolving favorably.
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ABSTRACT COVID-19-Associated Pulmonary Aspergillosis (CAPA) is a relatively common complication in patients with severe forms of the disease caused by the SARS-CoV-2 virus. Diagnosing and confirming CAPA is challenging. In this study, Aspergillus spp. isolation in respiratory specimens from patients with COVID-19 was evaluated for identifying cases of CAPA. In 2020-2021, 17 Aspergillus spp. were isolated from 15 COVID-19 patients admitted to a university hospital in Brazil. Patient records were retrospectively reviewed to obtain clinical-epidemiological data and other markers of Aspergillus spp. infection and then compared with the ECMM/ISHAM criteria for defining CAPA. Probable CAPA was defined in 5/10 patients, who had Aspergillus spp. isolated from Bronchoalveolar Lavage (BAL) or a positive galactomannan blood test. Additionally, anti-Aspergillus antibodies were detected in two of these patients, during active or follow-up phases of CAPA. In another seven patients with Aspergillus spp. isolated from tracheobronchial aspirate or sputum, CAPA was presumed, mainly due to deterioration of clinical conditions and new lung imaging suggestive of fungal infection. Antifungal agents to control CAPA, particularly voriconazole, were used in 9/15 cases. In cases of probable CAPA and remaining patients, clinical conditions and comorbidities were similar, with lethality being high, at 60% and 71%, respectively. The number of CAPA cases defined by scientific criteria was lower than that assumed in the clinical context. This was largely due to the lack of BAL collection for fungal culture and the non-intensive use of other markers of invasive aspergillosis. The isolation of Aspergillus spp. in different respiratory specimens should alert clinicians to the diagnosis of CAPA.
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ABSTRACT Paracoccidioidomycosis (PCM) may present as an acute/subacute clinical form, characterized by a progressive disease arising from the airborne initial infection, or, most often, as an asymptomatic or subclinical infection that may manifest later during an individual's life, the chronic form. Epidemiological studies show the existence of a strong association between smoking and the development of the chronic form. Current evidence demonstrates that cigarette smoke (CS) has immunosuppressive properties that could be implicated in the increasing susceptibility to the chronic form of PCM. To address this issue, we developed a murine model of a non-progressive pulmonary form of PCM that was exposed to CS at a magnitude that mimicked a moderate smoker. The chronic CS exposure started after 2 weeks and lasted up until 20 weeks post-infection, with the aim of mimicking human natural history, since it is estimated that individuals from endemic areas are infected early in life. The control group consisted of infected but not CS-exposed mice. We assessed the lung fungal burden (colony forming units [CFU]) and the area affected by the granulomatous inflammatory response, fungal dissemination to spleen and liver, and, by immunohistochemistry, the presence of CD4 and CD8 lymphocytes, CD68 and MAC-2 macrophages, and IFN-γ, IL-10 and TNF expressing cells within the granulomatous response. We detected a CS effect as early as 2 weeks after exposure (four weeks post-infection) when the lung CFU of exposed animals was significantly higher than in their non-exposed counterparts. At 12 weeks, the CS-exposed animals presented a more severe disease, as witnessed by the persistent higher lung fungal load (although it did not reach statistical significance [ p = 0.054]), greater dissemination to other organs, greater affected area of the lung, decreased IFN-γ/IL-10 ratio, and higher TNF expression within the granulomas, compared with CS-non-exposed mice. The number of CD4 and CD8 lymphocytes infiltrating the granulomas was similar between both mice groups, but there was a decrease in the number of MAC-2+ macrophages. No difference was noted in the CD68+ macrophage number. However, the follow-up in week 20 showed that the immunological effects of exposure to CS ceased, with both CS and NCS mice showing the same infectious features, i.e., a trend for resolution of the infection. In conclusion, we show that chronic CS-exposure alters the course of the disease in an experimental model of subclinical pulmonary PCM, confirming the epidemiological link between CS-exposure and the chronic form of PCM. However, we also show that this effect is transitory, being detected between 4- and 12-weeks post-infection but not thereafter. The possible immune mechanisms that mediate this effect and the reasons for its transitory effect are discussed.
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OBJECTIVES: Telomeres are a terminal "DNA cap" that prevent chromosomal fusion and degradation. However, aging is inherent to life, and so is the loss of terminal sequences. Telomerase is a specialized reverse transcriptase encoded by self-splicing introns that counteract chromosome erosion. Telomerase activity is observed during early embryonic development, but after the blastocyst stage, the expression of telomerase reduces. The consequences of either insufficient or unrestrained telomerase activity underscore the importance of ongoing studies aimed at elucidating the regulation of telomerase activity in humans. In the present study, we aimed to standardize a simplified telomerase repeat-amplification protocol (TRAP) assay to detect telomerase activity in unstimulated and PHA-stimulated mononuclear cells. METHODS and RESULTS: Our optimized qPCR-based can efficiently evaluate telomerase activity. Quantification of protein and DNA between unstimulated and PHA-stimulated peripheral blood mononuclear cells revealed cellular activation and cell-cycle entry. The assay also showed that relative telomerase activity is significantly different between these two conditions, supporting the applicability of the assay. Furthermore, our findings corroborated that telomerase activity decreases with age. CONCLUSIONS: Telomeres and telomerase are implicated in aging and development of chronic diseases and cancer; however, difficulty in accessing commercial kits to investigate these aspects is a critical constraint in health surveillance studies. Our optimized assay was successfully used to differentiate telomerase activity between unstimulated and stimulated cells, clearly showing the reactivation of telomerase upon cell activation. This assay is affordable, reproducible, and can be executed in resource-limited settings.
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Humanos , Femenino , Embarazo , Telomerasa/genética , Telomerasa/metabolismo , Neoplasias , Envejecimiento , Leucocitos Mononucleares/metabolismo , Enfermedad Crónica , Análisis Costo-BeneficioRESUMEN
OBJECTIVES: Immunosenescence is an age-associated change characterized by a decreased immune response. Although physical activity has been described as fundamental for maintaining the quality of life, few studies have evaluated the effects of different levels of exercise on telomere length in aged populations. The present study aimed to analyze the effects of different levels of physical activity, classified by the Maximal oxygen consumption (VO2 max) values, on the telomere length of memory Cluster of differentiation (CD) CD4+(CD45ROneg and CD45RO+), effector CD8+CD28neg, and CD8+CD28+ T cells in aged individuals. METHODS: Fifty-three healthy elderly men (aged 65-85 years) were included in this study. Their fitness level was classified according to the American College of Sports Medicine (ACSM) for VO2 max (mL/kg/min). Blood samples were obtained from all participants to analyze the percentage of CD3, CD4, CD8, CD28+, naïve, and subpopulations of memory T cells by using flow cytometry. Furthermore, using the Flow-FISH methodology, the CD4+CD45RO+, CD4+CD45ROneg, CD8+CD28+, and CD8+CD28negT cell telomere lengths were measured. RESULTS: There was a greater proportion of effector memory T CD4+ cells and longer telomeres in CD8+CD28+ T cells in the moderate physical fitness group than in the other groups. There was a higher proportion of terminally differentiated memory effector T cells in the low physical fitness group. CONCLUSION: A moderate physical activity may positively influence the telomere shortening of CD28+CD8+T cells. However, additional studies are necessary to evaluate the importance of this finding with regard to immune function responses in older men.
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Humanos , Masculino , Anciano , Anciano de 80 o más Años , Calidad de Vida , Telómero , Aptitud Física , Linfocitos T CD8-positivos , Citometría de FlujoRESUMEN
Sporotrichosis is a global implantation or subcutaneous mycosis caused by several members of the genus Sporothrix, a thermo-dimorphic fungus. This disease may also depict an endemic profile, especially in tropical to subtropical zones around the world. Interestingly, sporotrichosis is an anthropozoonotic disease that may be transmitted to humans by plants or by animals, especially cats. It may be associated with rather isolated or clustered cases but also with outbreaks in different periods and geographic regions. Usually, sporotrichosis affects immunocompetent hosts, presenting a chronic to subacute evolution course. Less frequently, sporotrichosis may be acquired by inhalation, leading to disseminated clinical forms. Both modes of infection may occur in immunocompromised patients, especially associated with human immunodeficiency virus (HIV) infection, but also diabetes mellitus, chronic alcoholism, steroids, anti-TNF treatment, hematologic cancer and transplanted patients. Similar to other endemic mycoses caused by dimorphic fungi, sporotrichosis in immunocompromised hosts may be associated with rather more severe clinical courses, larger fungal burden and longer periods of systemic antifungal therapy. A prolonged outbreak of cat-transmitted sporotrichosis is in progress in Brazil and potentially crossing the border to neighboring countries. This huge outbreak involves thousands of human and cats, including immunocompromised subjects affected by HIV and FIV (feline immunodeficiency virus), respectively. We reviewed the main epidemiologic, clinical, diagnostic and therapeutic aspects of sporotrichosis in immunocompromised hosts
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Humanos , Animales , Masculino , Persona de Mediana Edad , Esporotricosis , Infecciones Oportunistas , Síndrome de Inmunodeficiencia Adquirida , VIH , Huésped Inmunocomprometido , Síndrome Inflamatorio de Reconstitución InmuneRESUMEN
Two distinct patterns of immune recovery inflammatory syndrome (IRIS) are recognized, paradoxical and unmasking IRIS. Here we raise some concerns regarding the first case of neuroPCM-IRIS published to date, as recently proposed by Almeida and Roza (Mycopathologia 177:137-141, 2017) for a patient originally described by Silva-Vergara et al. (Mycopathologia 182:393-396, 2014), taking in account the different case definitions for IRIS and the cases of neuroparacoccidioidomycosis already described in the literature. We are concerned that data from the case report have been misinterpreted and that no regard has been given to the possibility that the development of manifestations of neuroPCM after starting antiretroviral therapy and antifungal treatments could represent the predicted course of a missed neuroPCM diagnosis at presentation whose treatment failed. We hypothesize that diagnosis of the neuroPCM would not have been missed if careful screening for opportunistic infection of the central nervous system was performed prior to antiretroviral therapy initiation. Currently, there is no definitive diagnostic test for IRIS and diagnostic suspicion, as well as its management, are based on image studies and non-specific clinical signs and symptoms of inflammation. IRIS remains a diagnosis of exclusion, after considering drug toxicity, microbiologic treatment failure and the expected course of newly or previously diagnosed opportunistic infections
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Humanos , Paracoccidioidomicosis , VIH , Síndrome Inflamatorio de Reconstitución InmuneRESUMEN
Negative results in serological routine screening of patients with microbiologically proven aracoccidioidomycosis (PCM) are occasionally reported. Failure in detecting anti-Paracoccidioides antibodies has been ascribed to factors either related to serological techniques or to the status of the host immune reactivity. Recently, this issue has been renewed by the recognition that the Paracoccidioides genera comprises two species, lutzii and brasiliensis, which have distinct antigenic profiles and, therefore, may elicit different host antibody responses. We describe a patient with the acute form PCM due to Paracoccidioides brasiliensis with negative results on two reference centers' routine screening for P. brasiliensis antibodies, but positive results with Paracoccidioides lutzii antigens. The present case report suggests that antibodies elicited during P. brasiliensis infection recognize antigenic fractions shared by both species, highlighting the difficulties in distinguishing the two infections by means of the currently available routine serological assays
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Humanos , Masculino , Adolescente , Paracoccidioides , Paracoccidioidomicosis/diagnósticoRESUMEN
A paracoccidioidomicose (PCM) é uma micose sistêmica, relacionada às atividades agrícolas, com incidência e prevalência subestimadas, pela ausência de notificação em várias Unidades da Federação (UFs). A evolução insidiosa do quadro clínico pode ter como consequência sequelas graves se o diagnóstico e o tratamento não forem instituídos precoce e adequadamente. Ao lado do complexo Paracoccidioides brasiliensis (P. brasiliensis), a descrição de nova espécie, Paracoccidioides lutzii (P. lutzii), em Rondônia, onde a doença alcançou níveis epidêmicos, bem como na região Centro-Oeste e no Pará, constituem-se em desafios para a instituição do diagnóstico e a urgente disponibilização de antígenos que tenham reatividade com os soros dos pacientes. Este consenso visa atualizar o primeiro consenso brasileiro em PCM, estabelecendo recomendações para o manejo clínico do paciente, com base nas evidências conhecidas. São apresentados dados de etiologia, epidemiologia, imunopatogenia, diagnóstico, terapêutica e sequelas, enfatizando-se o diagnóstico e a terapêutica, bem como recomendações e desafios atuais nessa área do conhecimento
Paracoccidioidomycosis is a systemic fungal disease associated with agricultural activities. Its incidence and prevalence are underestimated because of the lack of reporting in several Brazilian states. If paracoccidiodomycosis is not diagnosed and treated early and adequately, endemic fungal infection may result in serious sequelae. In addition to the Paracoccidioides brasiliensis (P. brasiliensis) complex, the appearance of a new species, Paracoccidioides lutzii (P. lutzii), in Rondônia state, where the disease has reached epidemic levels, and in the country's Midwest region and Pará state, are challenges to diagnosis and to the urgent availability of antigens that are reactive with patients' sera. These guidelines aim to update the first Brazilian consensus on paracoccidioidomycosis by providing evidence-based recommendations for bedside patient management. The guidelines provide data on etiology, epidemiology, immunopathogenesis, diagnosis, treatment and sequelae, with emphasis on diagnosis and treatment, as well as current recommendations and challenges in this field of knowledge
La paracoccidioidomicosis es una micosis sistémica, relacionada con las actividades agrícolas, con incidencia y prevalencia subestimadas por la ausencia de notificación en varios estados. La evolución insidiosa del cuadro clínico puede tener como consecuencia secuelas graves si el diagnóstico y el tratamiento no se establecen precoz y adecuadamente. Al lado del complejo Paracoccidioides brasiliensis (P. brasiliensis), la descripción de nueva especie, Paracoccidioides lutzii (P. lutzii) en Rondonia, donde la enfermedad alcanzó niveles epidémicos, y en la región Centro Oeste y en Pará, se constituyen en desafíos para la institución del diagnóstico y la urgente puesta a disposición de antígenos que tengan reactividad con los sueros de los pacientes. El presente consenso tiene por objeto actualizar el primer consenso brasileño en paracoccidioidomicosis, estableciendo recomendaciones para el manejo del paciente al borde del lecho, con base en las evidencias conocidas. Se presentan datos de etiología, epidemiología, inmunopatogenia, diagnóstico, terapéutica y secuelas, enfatizando el diagnóstico y terapéutica, así como recomendaciones desafíos y actuales en esta área del conocimiento
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Humanos , Masculino , Femenino , Niño , Adulto , Paracoccidioidomicosis/diagnóstico , Paracoccidioidomicosis/tratamiento farmacológico , Paracoccidioidomicosis/epidemiologíaRESUMEN
Abstract Paracoccidioidomycosis is a systemic fungal disease occurring in Latin America that is associated with rural environments and agricultural activities. However, the incidence and prevalence of paracoccidiodomycosis is underestimated because of the lack of compulsory notification. If paracoccidiodomycosis is not diagnosed and treated early and adequately, the endemic fungal infection could result in serious sequelae. While the Paracoccidioides brasiliensis ( P. brasiliensis ) complex has been known to be the causal agent of paracoccidiodomycosis, a new species, Paracoccidioides lutzii ( P. lutzii ), has been reported in Rondônia, where the disease has reached epidemic levels, and in the Central West and Pará. Accurate diagnoses and availability of antigens that are reactive with the patients' sera remain significant challenges. Therefore, the present guidelines aims to update the first Brazilian consensus on paracoccidioidomycosis by providing evidence-based recommendations for bedside patient management. This consensus summarizes etiological, ecoepidemiological, molecular epidemiological, and immunopathological data, with emphasis on clinical, microbiological, and serological diagnosis and management of clinical forms and sequelae, as well as in patients with comorbidities and immunosuppression. The consensus also includes discussion of outpatient treatments, severe disease forms, disease prevalence among special populations and resource-poor settings, a brief review of prevention and control measures, current challenges and recommendations.
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Humanos , Paracoccidioidomicosis/diagnóstico , Paracoccidioidomicosis/tratamiento farmacológico , Paracoccidioidomicosis/epidemiologíaRESUMEN
Several aspects of the natural history of paracoccidioidomycosis are still poorly understood. Different from the most prevalent, chronic form of the disease, the acute form represents a continuum from the initial respiratory infection to the full-blown disease, thus providing an opportunity to elucidate the pathogenesis of the early phase of this mycosis. We describe, for the first time, two patients with a single time point exposure to Paracoccidioides spp., for whom we were able to determine the time lapsed between exposure to the fungus Paracoccidioides spp. and the onset of signs and symptoms. In case 1, the pulmonary infection was unapparent, and the first manifestations of the acute/subacute form of the disease presented 4 months after Paracoccidioides spp. exposure. In case 2, self-limited, non-specific respiratory and systemic symptoms presented 45 days after infection. Thus, our patients confirm that, within a few weeks of infection, Paracoccidioides spp. affects the pulmonary lymphatic system and initially causes no or mild-to-moderate self-limited symptoms, eventually causing abnormalities on a chest X-ray, all of which spontaneously subside. These cases provide some insight into the natural history of this mycosis, the extent of the host exposure to the fungus, and the determination of its incubation period
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Humanos , Masculino , Femenino , Adolescente , Adulto , Paracoccidioides , Paracoccidioidomicosis/historiaRESUMEN
Leprosy is a chronic granulomatous infectious disease and is still endemic in many parts of the world. It causes disabilities which are the consequence of nerve damage. This damage is in most cases the result of immunological reactions...
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Humanos , Masculino , Femenino , Biopsia , Granuloma , Lepra , Mycobacterium leprae , PatologíaRESUMEN
There are few studies on the role of innate immune response in dermatophytosis. An investigation was conducted to define the involvement of Toll-Like Receptors (TLRs) 2 and 4 in localized (LD) and disseminated (DD) dermatophytosis due to T. rubrum. Fifteen newly diagnosed patients, eight patients with LD and seven with DD, defined by involvement of at least three body segments were used in this study. Controls comprised twenty skin samples from healthy individuals undergoing plastic surgery. TLR2 and TLR4 were quantified in skin lesions by immunohistochemistry. A reduced expression of TLR4 in the lower and upper epidermis of both LD and DD patients was found compared to controls; TLR2 expression was preserved in the upper and lower epidermis of all three groups. As TLR4 signaling induces the production of inflammatory cytokines and neutrophils recruitment, its reduced expression likely contributed to the lack of resolution of the infection and the consequent chronic nature of the dermatophytosis. As TLR2 expression acts to limit the inflammatory process and preserves the epidermal structure, its preserved expression may also contribute to the persistent infection and limited inflammation that are characteristic of dermatophytic infections.
A literatura sobre o papel da resposta imune inata em dermatofitose é escassa. Este estudo se propôs a investigar a participação dos receptores do tipo Toll 2 e 4 (TLRs) 2 e 4 em pacientes com dermatofitose localizada (LD) e disseminada (DD, definida como lesões em pelo menos três segmentos corpóreos distintos), causadas por Trichophyton rubrum. Foram analisados cortes histológicos de 15 pacientes recém-diagnosticados, oito com LD e sete com DD. O grupo controle foi composto por 20 amostras de pele de indivíduos saudáveis submetidos a cirurgia plástica. TLR-2 e TLR-4 foram quantificados em lesões cutâneas por imunohistoquímica. Encontramos uma expressão reduzida de TLR-4 na epiderme superior e inferior nos dois grupos, LD e DD, quando comparados com o grupo controle; a expressão de TLR-2 foi preservada na epiderme superior e inferior de todos os três grupos. Como a sinalização por TLR-4 induz produção de citocinas inflamatórias e recrutamento de neutrófilos, a menor expressão desta molécula provavelmente contribui para a não resolução da infecção e conseqüente natureza persistente da dermatofitose. Como a sinalização via TLR-2 tem sido descrita como fator de regulação do processo inflamatório e de preservação da estrutura epidérmica, a sua expressão inalterada nas lesões dos pacientes com DD e DL pode contribuir também para a persistência da infecção e do reduzido processo inflamatório que são característicos das infecções por dermatófitos.
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Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Queratinocitos/metabolismo , Tiña/metabolismo , /metabolismo , /metabolismo , Estudios de Casos y Controles , Inmunohistoquímica , Tiña/patologíaRESUMEN
The fungal strain Paracoccidioides brasiliensis remains viable inside of epithelial cells and can induce apoptosis in this population. However, until now, the molecules that participate in this process remained unknown. Thus, this study evaluated the contribution of two P. brasiliensis molecules, the 14-3-3 and glycoprotein of 43 kDa proteins, which had been previously described as extracellular matrix adhesins and apoptosis inductors in human pneumocytes. Accordingly, epithelial cells were treated with these molecules for different periods of time and the expression of the apoptosis regulating-proteins Bak, Bax, Bcl-2, p53 and caspases were evaluated by terminal deoxynucleotidyl transferase dUTP nick end labelling, flow cytometry and real-time polymerase chain reaction analysis. Our results demonstrated that treatment with these molecules induces apoptosis signalling in pulmonary epithelial cells, showing the same pattern of programmed cell-death as that observed during infection with P. brasiliensis. Thus, we could conclude that P. brasiliensis uses these molecules as virulence factors that participate not only in the fungal adhesion process to host cells, but also in other important cellular mechanisms such as apoptosis.
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Humanos , Apoptosis , Antígenos Fúngicos/fisiología , /fisiología , Células Epiteliales/microbiología , Proteínas Fúngicas/fisiología , Glicoproteínas/fisiología , Paracoccidioides/fisiología , Línea Celular/microbiología , Citometría de Flujo , Etiquetado Corte-Fin in Situ , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
OBJECTIVES: Chronic paracoccidioidomycosis can diffusely affect the lungs. Even after antifungal therapy, patients may present with residual respiratory abnormalities due to fungus-induced lung fibrosis. METHODS: A cross-sectional analysis of 50 consecutive inactive, chronic paracoccidioidomycosis patients was performed using high resolution computed tomography, pulmonary function tests, ergospirometry, the six-minute walk test and health-related quality of life questionnaires. RESULTS: Radiological abnormalities were present in 98% of cases, the most frequent of which were architectural distortion (90%), reticulate and septal thickening (88%), centrilobular and paraseptal emphysema (84%) and parenchymal bands (74%). Patients typically presented with a mild obstructive disorder and a mild reduction in diffusion capacity with preserved exercise capacity, including VO2max and six-minute walking distance. Patient evaluation with the Saint-George Respiratory Questionnaire showed low impairment in the health-related quality of life, and the Medical Research Council questionnaire indicated a low dyspnea index. There were, however, patients with significant oxygen desaturation upon exercise that was associated with respiratory distress compared with the non-desaturated patients. The initial counterimmunoelectrophoresis of these patients was higher and lung emphysema was more prominent; however, there were no differences in the interstitial fibrotic tomographic abnormalities, tobacco exposure, functional responses, exercise capacity or quality of life. CONCLUSIONS: Inactive, chronic paracoccidioidomycosis patients show persistent and disseminated radiological abnormalities by high resolution computed tomography, short impairments in pulmonary function and low impacts on aerobic capacity and quality of life. However, there was a subset of individuals whose functional impairment was more severe. These patients present with higher initial ...
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Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pulmón/fisiopatología , Paracoccidioidomicosis/fisiopatología , Estudios Transversales , Métodos Epidemiológicos , Fibrosis/microbiología , Fibrosis/patología , Fibrosis/fisiopatología , Pulmón/microbiología , Pulmón/patología , Consumo de Oxígeno/fisiología , Paracoccidioidomicosis/patología , Calidad de Vida , Pruebas de Función Respiratoria , Fumar/efectos adversos , Factores de Tiempo , Tomografía Computarizada por Rayos XRESUMEN
The aim of the study was to detect the rDNA sequences and their regions in Histoplasma capsulatum, which could be considered species-specific and used as a molecular method for this diagnosis by the technique of nested polymerase chain reaction (nested PCR), employing specific sequences (primers) for H. capsulatum: 18S rDNA region (HC18), 100 kDa (HC100) and the sequence 5.8 S-ITS rDNA (HC5.8). The PCR sequences HC18, HC100 and HC5.8 resulted in a specificity of 100%. The molecular assays may increase the specificity, sensitivity and speed in the diagnosis of Histoplasmosis.
O objetivo do estudo consistiu em detectar seqüências no ADNr e as suas regiões no Histoplasma capsulatum, que pudessem ser consideradas espécie-específicas e usadas como método molecular para o diagnóstico pela técnica da reação em cadeia da polimerase aninhada ("nested PCR") com seqüências específicas ("primers") para H. capsulatum: regiões 18S ADNr (HC18), 100kDa (HC100) e a seqüência 5.8 S ADNr-ITS (HC5.8). A "nested PCR" com as seqüências HC18, HC100 e HC5.8 resultaram em 100% de especificidade. Os ensaios moleculares podem aumentar a especificidade, sensibilidade e rapidez na diagnose da Histoplasmose.