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1.
Braz. j. infect. dis ; 27(4): 102793, 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1513873

ABSTRACT

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.

2.
Article in English | LILACS-Express | LILACS | ID: biblio-1529448

ABSTRACT

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.

3.
Article in English | LILACS-Express | LILACS | ID: biblio-1406881

ABSTRACT

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.

4.
Clinics ; 76: e2432, 2021. tab, graf
Article in English | LILACS | ID: biblio-1153954

ABSTRACT

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.


Subject(s)
Humans , Female , Pregnancy , Telomerase/genetics , Telomerase/metabolism , Neoplasms , Aging , Leukocytes, Mononuclear/metabolism , Chronic Disease , Cost-Benefit Analysis
6.
Clinics ; 75: 1628, 2020. tab, graf
Article in English | LILACS | ID: biblio-1133467

ABSTRACT

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.


Subject(s)
Humans , Male , Aged , Aged, 80 and over , Quality of Life , Telomere , Physical Fitness , CD8-Positive T-Lymphocytes , Flow Cytometry
7.
Mem. Inst. Oswaldo Cruz ; 110(4): 476-484, 09/06/2015. tab, graf
Article in English | LILACS | ID: lil-748870

ABSTRACT

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.


Subject(s)
Humans , Apoptosis , Antigens, Fungal/physiology , /physiology , Epithelial Cells/microbiology , Fungal Proteins/physiology , Glycoproteins/physiology , Paracoccidioides/physiology , Cell Line/microbiology , Flow Cytometry , In Situ Nick-End Labeling , Real-Time Polymerase Chain Reaction
8.
Rev. Inst. Med. Trop. Säo Paulo ; 57(1): 57-61, Jan-Feb/2015. graf
Article in English | LILACS | ID: lil-736361

ABSTRACT

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.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Keratinocytes/metabolism , Tinea/metabolism , /metabolism , /metabolism , Case-Control Studies , Immunohistochemistry , Tinea/pathology
9.
J. bras. pneumol ; 39(3): 368-372, jun. 2013. tab, graf
Article in English | LILACS | ID: lil-678264

ABSTRACT

On HRCT scans, lung cysts are characterized by rounded areas of low attenuation in the lung parenchyma and a well-defined interface with the normal adjacent lung. The most common cystic lung diseases are lymphangioleiomyomatosis, Langerhans cell histiocytosis, and lymphocytic interstitial pneumonia. In a retrospective analysis of the HRCT findings in 50 patients diagnosed with chronic paracoccidioidomycosis, we found lung cysts in 5 cases (10%), indicating that patients with paracoccidioidomycosis can present with lung cysts on HRCT scans. Therefore, paracoccidioidomycosis should be included in the differential diagnosis of cystic lung diseases. .


Os cistos pulmonares na TCAR são caracterizados por áreas arredondadas de baixo coeficiente de atenuação no parênquima pulmonar com uma interface bem definida com o pulmão adjacente normal. As doenças pulmonares císticas mais comuns são linfangioleiomiomatose, histiocitose de células de Langerhans e pneumonia intersticial linfocítica. Em uma análise retrospectiva de achados de TCAR em 50 pacientes com diagnóstico de paracoccidioidomicose crônica residual, observou-se a presença de cistos pulmonares em 5 casos (10%), mostrando que pacientes com paracoccidioidomicose podem apresentar cistos pulmonares na TCAR. Portanto, essa infecção deve entrar no diagnóstico diferencial das doenças císticas pulmonares. .


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Cysts , Lung Diseases, Fungal , Paracoccidioidomycosis , Smoking/adverse effects , Chronic Disease , Cysts/complications , Outpatients , Paracoccidioidomycosis/complications , Tomography, X-Ray Computed
10.
Clinics ; 68(4): 441-448, abr. 2013. tab, graf
Article in English | LILACS | ID: lil-674238

ABSTRACT

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 ...


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Lung/physiopathology , Paracoccidioidomycosis/physiopathology , Cross-Sectional Studies , Epidemiologic Methods , Fibrosis/microbiology , Fibrosis/pathology , Fibrosis/physiopathology , Lung/microbiology , Lung/pathology , Oxygen Consumption/physiology , Paracoccidioidomycosis/pathology , Quality of Life , Respiratory Function Tests , Smoking/adverse effects , Time Factors , Tomography, X-Ray Computed
11.
An. bras. dermatol ; 88(1): 141-143, fev. 2013.
Article in English | LILACS | ID: lil-667948

ABSTRACT

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.


Subject(s)
Humans , HIV Seropositivity/blood , Histoplasma/genetics , Histoplasmosis/diagnosis , Polymerase Chain Reaction , Early Diagnosis , Histoplasma/isolation & purification , Histoplasmosis/blood , Histoplasmosis/microbiology , Sensitivity and Specificity
12.
Mem. Inst. Oswaldo Cruz ; 107(supl.1): 167-173, Dec. 2012. ilus, graf
Article in English | LILACS, SES-SP | ID: lil-659755

ABSTRACT

Leprosy is a spectral disease exhibiting two polar sides, namely, lepromatous leprosy (LL) characterised by impaired T-cell responses and tuberculoid leprosy in which T-cell responses are strong. Proper T-cell activation requires signalling through costimulatory molecules expressed by antigen presenting cells and their ligands on T-cells. We studied the influence of costimulatory molecules on the immune responses of subjects along the leprosy spectrum. The expression of the costimulatory molecules was evaluated in in vitro-stimulated peripheral blood mononuclear cells of lepromatous and tuberculoid patients and healthy exposed individuals (contacts). We show that LL patients have defective monocyte CD86 expression, which likely contributes to the impairment of the antigen presentation process and to patients anergy. Accordingly, CD86 but not CD80 blockade inhibited the lymphoproliferative response to Mycobacterium leprae. Consistent with the LL anergy, there was reduced expression of the positive signalling costimulatory molecules CD28 and CD86 on the T-cells in these patients. In contrast, tuberculoid leprosy patients displayed increased expression of the negative signalling molecules CD152 and programmed death-1 (PD-1), which represents a probable means of modulating an exacerbated immune response and avoiding immunopathology. Notably, the contacts exhibited proper CD86 and CD28 expression but not exacerbated CD152 or PD-1 expression, suggesting that they tend to develop a balanced immunity without requiring immunosuppressive costimulatory signalling.


Subject(s)
Adult , Female , Humans , Male , /immunology , /immunology , /immunology , Leprosy/microbiology , Mycobacterium leprae/immunology , Programmed Cell Death 1 Receptor/immunology , T-Lymphocytes/immunology , /metabolism , /metabolism , /metabolism , Case-Control Studies , Host-Parasite Interactions , Leprosy/immunology , Mycobacterium leprae/physiology , Programmed Cell Death 1 Receptor/metabolism
14.
An. bras. dermatol ; 86(4): 716-724, jul.-ago. 2011. ilus
Article in Portuguese | LILACS | ID: lil-600614

ABSTRACT

O uso dos inibidores do fator de necrose tumoral no tratamento de pacientes com psoríase vem sendo relacionado a uma maior incidência de tuberculose, particularmente, nas suas formas extrapulmonar e disseminada. Apesar de sua indiscutível eficácia, essas drogas elevam o risco da reativação de infecção tuberculosa latente (ITBL), tornando obrigatório o diagnóstico da referida condição antes da sua administração. A investigação da infecção tuberculosa latente pelo teste cutâneo da tuberculina é falha, dada sua baixa especificidade, além de apresentar resultados duvidosos em pacientes com psoríase. Ensaios baseados na detecção da produção de interferon-gama in vitro por células monoclonais periféricas, estimuladas por antígenos específicos (Esat-6 e CFP-10), parecem oferecer maior acurácia quando comparados ao teste de Mantoux na identificação de infecção tuberculosa latente. Essa ferramenta diagnóstica tem oferecido maior especificidade, já que não apresenta correlação com medidas indiretas de exposição ao M. tuberculosis, como a vacinação por BCG, e com infecções por outras micobactérias.


The use of tumor necrosis factor inhibitors for the treatment of patients with psoriasis has been related to a higher incidence of tuberculosis, specially the disseminated and extrapulmonary forms. Despite their efficacy, these drugs increase the risk of reactivating latent tuberculosis infection, thus requiring diagnosis of the condition before their administration. Investigation of latent tuberculosis infection with tuberculin skin test is ineffective due to its low specificity and the dubious results that it generates in patients with psoriasis. Assays based on the detection of synthesis of gamma interferon in vitro by peripheral monoclonal cells, stimulated by specific antigens (ESAT-6 and CFP-10), seem to offer better accuracy when compared to the Mantoux test in identifying latent tuberculosis infection. This diagnosis tool has demonstrated higher specificity, since it has no correlation with indirect forms of exposure to M. tuberculosis such as BCG vaccination or with infections by other mycobacteria.


Subject(s)
Humans , Latent Tuberculosis/chemically induced , Psoriasis/drug therapy , Tumor Necrosis Factor-alpha/adverse effects , Latent Tuberculosis/diagnosis , Latent Tuberculosis/immunology , Reproducibility of Results , Sensitivity and Specificity , Tumor Necrosis Factor-alpha/immunology , Tumor Necrosis Factor-alpha/therapeutic use
15.
Mem. Inst. Oswaldo Cruz ; 104(5): 749-754, Aug. 2009. ilus, graf
Article in English | LILACS | ID: lil-528085

ABSTRACT

Paracoccidioidomycosis presents a variety of clinical manifestations and Paracoccidioides brasiliensis can reach many tissues, most importantly the lungs. The ability of the pathogen to interact with host surface structures is essential to its virulence. The interaction between P. brasiliensis and epithelial cells has been studied, with particular emphasis on the induction of apoptosis. To investigate the expression of different apoptosis-inducing pathways in human A549 cells, we infected these cells with P. brasiliensis Pb18SP (subcultured) and 18R (recently isolated from cell culture and showing a high adhesion pattern) samples in vitro. The expressions of Bcl-2, Bak and caspase 3 were analysed by flow cytometry and DNA fragmentation using the TUNEL technique. Apoptosis of human A549 cells was induced by P. brasiliensis in a sample and time-dependent manner. Using an in vitro model, our data demonstrates that caspase 3, Bak, Bcl-2 and DNA fragmentation mediate P. brasiliensis-induced apoptosis in A549 cells. The overall mechanism is a complex process, which may involve several signal transduction pathways. These findings could partially explain the efficient behaviour of this fungus in promoting tissue infection and/or blood dissemination.


Subject(s)
Humans , Apoptosis/physiology , Epithelial Cells/microbiology , Host-Pathogen Interactions , Lung/cytology , Paracoccidioides/physiology , /analysis , Cell Line/microbiology , Flow Cytometry , Paracoccidioides/pathogenicity , /analysis , /analysis
16.
Clinics ; 63(5): 667-676, 2008.
Article in English | LILACS | ID: lil-495043

ABSTRACT

OBJECTIVES: The present study aimed to evaluate the dynamics of CD28 and CD57 expression in CD8+ T lymphocytes during cytomegalovirus viremia in bone marrow transplant recipients. METHODS: In a prospective study, blood samples were obtained once weekly once from 33 healthy volunteers and weekly from 33 patients. To evaluate the expression of CD57 and CD28 on CD8+ T lymphocytes, flow cytometry analysis was performed on blood samples for four months after bone marrow transplant, together with cytomegalovirus antigenemia assays. RESULTS: Compared to cytomegalovirus-seronegative healthy subjects, seropositive healthy subjects demonstrated a higher percentage of CD57+ and a lower percentage of CD28+ cells (p<0.05). A linear regression model demonstrated a continuous decrease in CD28+ expression and a continuous increase in CD57+ expression after bone marrow transplant. The occurrence of cytomegalovirus antigenemia was associated with a steep drop in the percentage of CD28+ cells (5.94 percent, p<0.01) and an increase in CD57+ lymphocytes (5.60 percent, p<0.01). This cytomegalovirus-dependent effect was for the most part concentrated in the allogeneic bone marrow transplant patients. The development of acute graft versus host disease, which occurred at an earlier time than antigenemia (day 26 vs. day 56 post- bone marrow transplant), also had an impact on the CD57+ subset, triggering an increase of 4.9 percent in CD57+ lymphocytes (p<0.05). CONCLUSION: We found continuous relative changes in the CD28+ and CD57+ subsets during the first 120 days post- bone marrow transplant, as part of immune system reconstitution and maturation. A clear correlation was observed between the expansion of the CD57+CD28-CD8+ T lymphocyte subpopulation and the occurrence of graft versus host disease and cytomegalovirus viremia.


Subject(s)
Adult , Female , Humans , Male , Young Adult , Antigens, CD/immunology , Bone Marrow Transplantation/immunology , /immunology , Cytomegalovirus Infections/immunology , Graft vs Host Disease/immunology , Viremia/immunology , /immunology , /immunology , /immunology , /virology , Cytomegalovirus Infections/blood , Cytomegalovirus Infections/prevention & control , Graft vs Host Disease/virology , Linear Models , Prospective Studies , Viremia/blood , Viremia/prevention & control , Young Adult
17.
Rev. Inst. Med. Trop. Säo Paulo ; 49(4): 215-219, Jul.-Aug. 2007.
Article in English | LILACS | ID: lil-460227

ABSTRACT

BACKGROUND: Before the introduction of highly active antiretroviral therapy (HAART), CMV retinitis was a common complication in patients with advanced HIV disease and the therapy was well established; it consisted of an induction phase to control the infection with ganciclovir, followed by a lifelong maintenance phase to avoid or delay relapses. METHODS: To determine the safety of CMV maintenance therapy withdrawal in patients with immune recovery after HAART, 35 patients with treated CMV retinitis, on maintenance therapy, with CD4+ cell count greater than 100 cells/mm³ for at least three months, but almost all patients presented these values for more than six months and viral load < 30000 copies/mL, were prospectively evaluated for the recurrence of CMV disease. Maintenance therapy was withdrawal at inclusion, and patients were monitored for at least 48 weeks by clinical and ophthalmologic evaluations, and by determination of CMV viremia markers (antigenemia-pp65), CD4+/CD8+ counts and plasma HIV RNA levels. Lymphoproliferative assays were performed on 26/35 patients. RESULTS: From 35 patients included, only one had confirmed reactivation of CMV retinitis, at day 120 of follow-up. No patient returned positive antigenemia tests. No correlation between lymphoproliferative assays and CD4+ counts was observed. CONCLUSION: CMV retinitis maintenance therapy discontinuation is safe for those patients with quantitative immune recovery after HAART.


Antes da introdução da terapia anti-retroviral altamente efetiva (HAART), a retinite por CMV era uma complicação comum em pacientes com doença por HIV avançada e a terapia era bem estabelecida e consistia em uma fase de indução com ganciclovir para controlar a infecção, seguida por uma manutenção por toda a vida, para evitar e retardar as recidivas. Para determinar a segurança da retirada da terapia de manutenção para retinite por citomegalovírus em pacientes com recuperação imunológica após o HAART, 35 pacientes com retinite por CMV tratados com terapia de manutenção, com contagem de células CD4+ maiores que 100 células/mm³ por no mínimo três meses, mas a maioria dos pacientes apresentava esses valores por mais de seis meses e carga viral < 30.000 cópias/mL, foram avaliados prospectivamente para a recorrência de doença por CMV. A terapia de manutenção foi retirada na inclusão e os pacientes foram monitorados no mínimo 48 semanas por avaliações clínicas e oftalmológicas e pela determinação de marcadores de viremia para CMV (antigenemia). Contagens de CD4+ e CD8+ e níveis de RNA de HIV no plasma. Métodos linfoproliferativos foram realizados em 26/35 pacientes. RESULTADOS: Dos 35 pacientes incluídos no estudo, somente um teve reativação da retinite por CMV confirmada, no dia 120 do seguimento. Nenhum paciente teve testes de antigenemia positivos. Nenhuma correlação entre os ensaios linfoproliferativos e contagens de CD4+ foi observada. CONCLUSÃO: Descontinuação da terapia de manutenção para retinite por CMV é segura para aqueles pacientes com recuperação imune quantitativa após HAART.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , AIDS-Related Opportunistic Infections/drug therapy , Anti-HIV Agents/therapeutic use , Cytomegalovirus Retinitis/drug therapy , AIDS-Related Opportunistic Infections/immunology , AIDS-Related Opportunistic Infections/virology , Antiretroviral Therapy, Highly Active , Cytomegalovirus Retinitis/immunology , Cytomegalovirus Retinitis/virology , Cytomegalovirus/immunology , Follow-Up Studies , Prospective Studies , Viral Load
18.
São Paulo med. j ; 114(3): 1186-9, maio-jun. 1996. graf
Article in English | LILACS, SES-SP | ID: lil-186684

ABSTRACT

Nineteen Brazilian HIV-infected hemophiliacs and their stable heterosexual sexual partners were studied with the aim of assessing the rate of HIV transmission in this at risk group. The mean length of relationship between couples was 7.4 years. The hemophiliac men were Class II (n=6),III (n=11) and IVa (n=2) of the CDC classification. They had decreased CD4+ and elevated CD8+ cell numbers; five had p24 antigenemia. We found 3 HIV-infected women (l5.8 percent) by routine and confirmatory tests, a prevalence similar to that seen in other countries. They were asymptomatic and had no detectable p24 antigenemia. The 3 seropositive women's partners were Class II and III-CDC, and had normal CD4+ and CD8+ values and no p24 antigenemia. All seronegative women also had normal CD4+ and CD8+ numbers, except for elevated CD8+ cells in three of them, but immune abnormalities had already been seen in some seronegative partners at high risk for HIV infection. Our results reinforce previous suggestions that heterosexual transmission to stable female partners occurs preferentially early after initiation of sexual exposure, and possibly when the transmitter has high levels of viremia and regular sexual activity.


Subject(s)
Adult , Middle Aged , Female , Humans , Adolescent , Sexual Partners , HIV Infections/transmission , Hemophilia A/complications , Blood Cell Count , Brazil , HIV Infections/immunology , Risk Factors
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