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Emergence and disappearance of a virulent clone of Haemophilus influenzae biogroup aegyptius, cause of Brazilian Purpuric Fever

HARRISON, Lee H; SIMONSEN, Vera; WALDMAN, Eliseu Alves
Fonte: Washington Publicador: Washington
Tipo: Artigo de Revista Científica
Português
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Summary: In 1984, children presented to the emergency department of a hospital in the small town of Promissão, São Paulo State, Brazil, with an acute febrile illness that rapidly progressed to death. Local clinicians and public health officials recognized that these children had an unusual illness, which led to outbreak investigations conducted by Brazilian health officials in collaboration with the U.S. Centers for Disease Control and Prevention. The studies that followed are an excellent example of the coordinated and parallel studies that are used to investigate outbreaks of a new disease, which became known as Brazilian purpuric fever (BPF). In the first outbreak investigation, a case-control study confirmed an association between BPF and antecedent conjunctivitis but the etiology of the disease could not be determined. In a subsequent outbreak, children with BPF were found to have bacteremia caused by Haemophilus influenzae biogroup aegyptius (H. aegyptius), an organism previously known mainly to cause self-limited purulent conjunctivitis. Molecular characterization of blood and other isolates demonstrated the clonal nature of the H. aegyptius strains that caused BPF, which were genetically distant from the diverse strains that cause only conjunctivitis. This led to an intense effort to identify the factors causing the unusual invasiveness of the BPF clone...

The frequency of CD127(low) expressing CD4(+)CD25(high) T regulatory cells is inversely correlated with human T lymphotrophic virus type-1 (HTLV-1) proviral load in HTLV-1-infection and HTLV-1-associated myelopathy/tropical spastic paraparesis

MICHAELSSON, Jakob; BARBOSA, Hugo Marcelo R.; JORDAN, Kimberley A.; CHAPMAN, Joan M.; BRUNIALTI, Milena K. C.; KLEINE NETO, Walter; NUKUI, Youko; SABINO, Ester C.; CHIEIA, Marco Antonio; OILIVEIRA, Acary Souza Bulle; NIXON, Douglas F.; KALLAS, Esper G.
Fonte: BIOMED CENTRAL LTD Publicador: BIOMED CENTRAL LTD
Tipo: Artigo de Revista Científica
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Background: CD4(+)CD25(high) regulatory T (T(Reg)) cells modulate antigen-specific T cell responses, and can suppress anti-viral immunity. In HTLV-1 infection, a selective decrease in the function of T(Reg) cell mediated HTLV-1-tax inhibition of FOXP3 expression has been described. The purpose of this study was to assess the frequency and phenotype of T(Reg) cells in HTLV-1 asymptomatic carriers and in HTLV-1-associated neurological disease (HAM/TSP) patients, and to correlate with measures of T cell activation. Results: We were able to confirm that HTLV-1 drives activation, spontaneous IFN gamma production, and proliferation of CD4+ T cells. We also observed a significantly lower proportion of CTLA-4(+) T(Reg) cells (CD4(+)CD25(high) T cells) in subjects with HAM/TSP patients compared to healthy controls. Ki-67 expression was negatively correlated to the frequency of CTLA-4(+) T(Reg) cells in HAM/TSP only, although Ki-67 expression was inversely correlated with the percentage of CD127(low) T(Reg) cells in healthy control subjects. Finally, the proportion of CD127(low) T(Reg) cells correlated inversely with HTLV-1 proviral load. Conclusion: Taken together, the results suggest that T(Reg) cells may be subverted in HAM/TSP patients, which could explain the marked cellular activation...

Skewed Distribution of Circulating Activated Natural Killer T (NKT) Cells in Patients with Common Variable Immunodeficiency Disorders (CVID)

CARVALHO, Karina I.; MELO, Karina M.; BRUNO, Fernanda R.; SNYDER-CAPPIONE, Jennifer E.; NIXON, Douglas F.; COSTA-CARVALHO, Beatriz T.; KALLAS, Esper G.
Fonte: PUBLIC LIBRARY SCIENCE Publicador: PUBLIC LIBRARY SCIENCE
Tipo: Artigo de Revista Científica
Português
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Common variable immunodeficiency disorder (CVID) is the commonest cause of primary antibody failure in adults and children, and characterized clinically by recurrent bacterial infections and autoimmune manifestations. Several innate immune defects have been described in CVID, but no study has yet investigated the frequency, phenotype or function of the key regulatory cell population, natural killer T (NKT) cells. We measured the frequencies and subsets of NKT cells in patients with CVID and compared these to healthy controls. Our results show a skewing of NKT cell subsets, with CD4+ NKT cells at higher frequencies, and CD8+ NKT cells at lower frequencies. However, these cells were highly activated and expression CD161. The NKT cells had a higher expression of CCR5 and concomitantly expression of CCR5+CD69+CXCR6 suggesting a compensation of the remaining population of NKT cells for rapid effector action.; National Institutes of Health (NIH)[R01-AI52731]; National Institutes of Health (NIH)[AI060379]; (NIH) Fogarty International Center[D43 TW00003]; Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Brazilian Ministry of Science and Technology

HTLV-1 Tax Specific CD8+ T Cells Express Low Levels of Tim-3 in HTLV-1 Infection: Implications for Progression to Neurological Complications

NDHLOVU, Lishomwa C.; LEAL, Fabio E.; HASENKRUG, Aaron M.; JHA, Aashish R.; CARVALHO, Karina I.; ECCLES-JAMES, Ijeoma G.; BRUNO, Fernanda R.; VIEIRA, Raphaella G. S.; YORK, Vanessa A.; CHEW, Glen M.; JONES, R. Brad; TANAKA, Yuetsu; NETO, Walter K.; SANABA
Fonte: PUBLIC LIBRARY SCIENCE Publicador: PUBLIC LIBRARY SCIENCE
Tipo: Artigo de Revista Científica
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The T cell immunoglobulin mucin 3 (Tim-3) receptor is highly expressed on HIV-1-specific T cells, rendering them partially ""exhausted' and unable to contribute to the effective immune mediated control of viral replication. To elucidate novel mechanisms contributing to the HTLV-1 neurological complex and its classic neurological presentation called HAM/TSP (HTLV-1 associated myelopathy/tropical spastic paraparesis), we investigated the expression of the Tim-3 receptor on CD8(+) T cells from a cohort of HTLV-1 seropositive asymptomatic and symptomatic patients. Patients diagnosed with HAM/TSP down-regulated Tim-3 expression on both CD8(+) and CD4(+) T cells compared to asymptomatic patients and HTLV-1 seronegative controls. HTLV-1 Tax-specific, HLA-A*02 restricted CD8(+) T cells among HAM/TSP individuals expressed markedly lower levels of Tim-3. We observed Tax expressing cells in both Tim-3(+) and Tim-3(-) fractions. Taken together, these data indicate that there is a systematic downregulation of Tim-3 levels on T cells in HTLV-1 infection, sustaining a profoundly highly active population of potentially pathogenic T cells that may allow for the development of HTLV-1 complications.; National Institutes of Health (NIH), University of California...

Characterization of Yeast Extracellular Vesicles: Evidence for the Participation of Different Pathways of Cellular Traffic in Vesicle Biogenesis

OLIVEIRA, Debora L.; NAKAYASU, Ernesto S.; JOFFE, Luna S.; GUIMARAES, Allan J.; SOBREIRA, Tiago J. P.; NOSANCHUK, Joshua D.; CORDERO, Radames J. B.; FRASES, Susana; CASADEVALL, Arturo; ALMEIDA, Igor C.; NIMRICHTER, Leonardo; RODRIGUES, Marcio L.
Fonte: PUBLIC LIBRARY SCIENCE Publicador: PUBLIC LIBRARY SCIENCE
Tipo: Artigo de Revista Científica
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Background: Extracellular vesicles in yeast cells are involved in the molecular traffic across the cell wall. In yeast pathogens, these vesicles have been implicated in the transport of proteins, lipids, polysaccharide and pigments to the extracellular space. Cellular pathways required for the biogenesis of yeast extracellular vesicles are largely unknown. Methodology/Principal Findings: We characterized extracellular vesicle production in wild type (WT) and mutant strains of the model yeast Saccharomyces cerevisiae using transmission electron microscopy in combination with light scattering analysis, lipid extraction and proteomics. WT cells and mutants with defective expression of Sec4p, a secretory vesicle-associated Rab GTPase essential for Golgi-derived exocytosis, or Snf7p, which is involved in multivesicular body (MVB) formation, were analyzed in parallel. Bilayered vesicles with diameters at the 100-300 nm range were found in extracellular fractions from yeast cultures. Proteomic analysis of vesicular fractions from the cells aforementioned and additional mutants with defects in conventional secretion pathways (sec1-1, fusion of Golgi-derived exocytic vesicles with the plasma membrane; bos1-1, vesicle targeting to the Golgi complex) or MVB functionality (vps23...

The-2518 bp promoter polymorphism at CCL2/MCP1 influences susceptibility to mucosal but not localized cutaneous leishmaniasis in Brazil

RAMASAWMY, Rajendranath; MENEZES, Eliane; MAGALHAES, Andrea; OLIVEIRA, Joyce; CASTELLUCCI, Lea; ALMEIDA, Roque; ROSA, Maria Elisa A.; GUIMARAES, Luiz Henrique; LESSA, Marcus; NORONHA, Elza; WILSON, Mary E.; JAMIESON, Sarra E.; KALIL, Jorge; BLACKWELL, Jen
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
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Mucosal leishmaniasis (ML) follows localized cutaneous leishmaniasis (CL) caused by Leishmania braziliensis. Proinflammatory responses mediate CL self-healing but are exaggerated in ML Proinflammatory monocyte chemoattractant protein 1 (MCP-1; encoded by CCL2) is associated with CL We explore its role in CL/ML through analysis of the regulatory CCL2 -2518 bp promoter polymorphism in CL/ML population samples and families from Brazil. Genotype frequencies were compared among ML/CL cases and control groups using logistic regression and the family-based association test (FBAT). MCP-1 was measured in plasma and macrophages. The GG recessive genotype at CCL2 -2518 bp was more common in patients with ML (N = 67) than in neighborhood control (NC; N = 60) subjects (OR 1.78; 95% Cl 1.01-3.14; P = 0.045), than in NC combined with leishmanin skin-test positive (N = 60) controls (OR 4.40; 95% CI 1.42-13.65; P = 0.010), and than in controls combined with CL (N = 60) patients (OR 2.78; 95% CI 1.13-6.85; P = 0.045). No associations were observed for CL compared to any groups. FBAT (91 ML and 223 CL cases in families) confirmed recessive association of ML with allele G (Z = 2.679; P = 0.007). Higher levels of MCP-1 occurred in plasma (P = 0.03) and macrophages (P < 0.0001) from GG compared to AA individuals. These results suggest that high MCP-1 increases risk of ML (C) 2010 Elsevier B.V. All rights reserved.; NIH[P50 AI-30639]; NIH[R03AI070909]; NIH/FIC[1 D43 TW007127-01]; NIH/FIC[R01 AI076233]; NIH/FIC[R01AI067874]; CNPq; VA Merit Review grant; Wellcome Trust

Model for Differential Nursing Diagnosis of Alterations in Urinary Elimination Based on Fuzzy Logic

LOPES, Maria Helena Baena De Moraes; ORTEGA, Neli Regina Siqueira; MASSAD, Eduardo; MARIN, Heimar De Fatima
Fonte: LIPPINCOTT WILLIAMS & WILKINS Publicador: LIPPINCOTT WILLIAMS & WILKINS
Tipo: Artigo de Revista Científica
Português
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Nursing diagnoses associated with alterations of urinary elimination require different interventions, Nurses, who are not specialists, require support to diagnose and manage patients with disturbances of urine elimination. The aim of this study was to present a model based on fuzzy logic for differential diagnosis of alterations in urinary elimination, considering nursing diagnosis approved by the North American Nursing Diagnosis Association, 2001-2002. Fuzzy relations and the maximum-minimum composition approach were used to develop the system. The model performance was evaluated with 195 cases from the database of a previous study, resulting in 79.0% of total concordance and 19.5% of partial concordance, when compared with the panel of experts. Total discordance was observed in only three cases (1.5%). The agreement between model and experts was excellent (kappa = 0.98, P < .0001) or substantial (kappa = 0.69, P < .0001) when considering the overestimative accordance (accordance was considered when at least one diagnosis was equal) and the underestimative discordance (discordance was considered when at least one diagnosis was different), respectively. The model herein presented showed good performance and a simple theoretical structure...

Early identification of leptospirosis-associated pulmonary hemorrhage syndrome by use of a validated prediction model

MAROTTO, Paulo C. F.; KO, Albert I.; MURTA-NASCIMENTO, Cristiane; SEGURO, Antonio C.; PRADO, Rogerio R.; BARBOSA, Marcia C.; CLETO, Sergio A.; ELUF-NETO, Jose
Fonte: W B SAUNDERS CO LTD Publicador: W B SAUNDERS CO LTD
Tipo: Artigo de Revista Científica
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Objective: To identify prediction factors for the development of leptospirosis-associated pulmonary hemorrhage syndrome (LPHS). Methods: We conducted a prospective cohort study. The study comprised of 203 patients, aged >= 14 years, admitted with complications of the severe form of leptospirosis at the Emilio Ribas Institute of Infectology (Sao Paulo, Brazil) between 1998 and 2004. Laboratory and demographic data were obtained and the severity of illness score and involvement of the lungs and others organs were determined. Logistic regression was performed to identify independent predictors of LPHS. A prospective validation cohort of 97 subjects with severe form of leptospirosis admitted at the same hospital between 2004 and 2006 was used to independently evaluate the predictive value of the model. Results: The overall mortality rate was 7.9%. Multivariate logistic regression revealed that five factors were independently associated with the development of LPHS: serum potassium (mmol/L) (OR = 2.6; 95% CI = 1.1-5.9); serum creatinine (mmol/L) (OR = 1.2; 95% CI = 1.1-1.4); respiratory rate (breaths/min) (OR = 1.1; 95% CI = 1.1-1.2); presenting shock (OR = 69.9; 95% CI = 20.1-236.4), and Glasgow Coma Scale Score (GCS) < 15 (OR = 7.7; 95% CI = 1.3-23.0). We used these findings to calculate the risk of LPHS by the use of a spreadsheet. In the validation cohort...

Increased number and function of natural killer cells in human immunodeficiency virus 1-positive subjects co-infected with herpes simplex virus 2

LONG, Brian R.; ERICKSON, Ann E.; CHAPMAN, Joan M.; BARBOUR, Jason D.; VU, Bien-Aimee N.; HO, Emily L.; LANIER, Lewis L.; SAUER, Mariana M.; CARVALHO, Karina I.; NIXON, Douglas F.; KALLAS, Esper G.
Fonte: WILEY-BLACKWELL PUBLISHING, INC Publicador: WILEY-BLACKWELL PUBLISHING, INC
Tipo: Artigo de Revista Científica
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P>Natural killer (NK) cells bridge the interface between innate and adaptive immunity and are implicated in the control of herpes simplex virus 2 (HSV-2) infection. In subjects infected with human immunodeficiency virus 1 (HIV-1), the critical impact of the innate immune response on disease progression has recently come into focus. Higher numbers of NK cells are associated with lower HIV-1 plasma viraemia. Individuals with the compound genotype of killer cell immunoglobulin-like receptor (KIR) 3DS1 and human leucocyte antigen (HLA)-Bw4-80I, or who have alleles of KIR3DL1 that encode proteins highly expressed on the NK cell surface, have a significant delay in disease progression. We studied the effect of HSV-2 co-infection in HIV-1-infected subjects, and show that HSV-2 co-infection results in a pan-lymphocytosis, with elevated absolute numbers of CD4+ and CD8+ T cells, and NK cells. The NK cells in HSV-2 co-infected subjects functioned more efficiently, with an increase in degranulation after in vitro stimulation. The number of NK cells expressing the activating receptors NKp30 and NKp46, and expressing KIR3DL1 or KIR3DS1, was inversely correlated with HIV-1 plasma viral load in subjects mono-infected with HIV-1, but not in subjects co-infected with HSV-2. This suggests that HSV-2 infection mediates changes within the NK cell population that may affect immunity in HIV-1 infection.; National Institute of Allergies and Infectious Diseases[NIAID AI060379]; National Institute of Allergies and Infectious Diseases[AI052731]; National Institute of Allergies and Infectious Diseases[AI064520]; National Institute of Allergies and Infectious Diseases[AI64520]; National Institute of Allergies and Infectious Diseases[AI-066917]; National Institute of Allergies and Infectious Diseases[AI-076014]; Brazilian Program; Ministry of Health[914/BRA/3014 - UNESCO/Kallas]; Sao Paulo City Health Department[2004-0.168.922-7/Kallas]; FAPESP Fundacao de Amparo a Pesquisa do Estado de Sao Paulo[04/15 856-9/Kallas]; John E. Fogarty International Center (FIRCA/NIH)[D43 TW00003]; AIDS Research Institute of the AIDS Biology Program at UCSF; Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)...

Lower numbers of circulating natural killer T (NK T) cells in individuals with human T lymphotropic virus type 1 (HTLV-1) associated neurological disease

NDHLOVU, L. C.; SNYDER-CAPPIONE, J. E.; CARVALHO, K. I.; LEAL, F. E.; LOO, C. P.; BRUNO, F. R.; JHA, A. R.; DEVITA, D.; HASENKRUG, A. M.; BARBOSA, H. M. R.; SEGURADO, A. C.; NIXON, D. F.; MURPHY, E. L.; KALLAS, E. G.
Fonte: WILEY-BLACKWELL PUBLISHING, INC Publicador: WILEY-BLACKWELL PUBLISHING, INC
Tipo: Artigo de Revista Científica
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Human T lymphotropic virus type 1 (HTLV-1) infects 10-20 million people worldwide. The majority of infected individuals are asymptomatic; however, approximately 3% develop the debilitating neurological disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). There is also currently no cure, vaccine or effective therapy for HTLV-1 infection, and the mechanisms for progression to HAM/TSP remain unclear. NK T cells are an immunoregulatory T cell subset whose frequencies and effector functions are associated critically with immunity against infectious diseases. We hypothesized that NK T cells are associated with HAM/TSP progression. We measured NK T cell frequencies and absolute numbers in individuals with HAM/TSP infection from two cohorts on two continents: Sao Paulo, Brazil and San Francisco, CA, USA, and found significantly lower levels when compared with healthy subjects and/or asymptomatic carriers. Also, the circulating NK T cell compartment in HAM/TSP subjects is comprised of significantly more CD4(+) and fewer CD8(+) cells than healthy controls. These findings suggest that lower numbers of circulating NK T cells and enrichment of the CD4(+) NK T subset are associated with HTLV-1 disease progression.; National Institute of Allergy and Infectious Diseases (NIAID/NIH)[R37AI052731]; National Heart Lung and Blood Institute (NHLBI/NIH)[2R01-HL-62235]; AIDS Research Institute of University of California San Francisco; Brazilian Program for STD and AIDS; Ministry of Health[914/BRA/3014 -UNESCO/Kallas]; Sao Paulo City Health Department[2004-0.168.922-7/Kallas]; FAPESP Fundacao de Amparo a Pesquisa do Estado de Sao Paulo[04/15856-9/Kallas]; John E. Fogarty International Center (FIRCA/NIH)[D43 TW00003]

Lower cytokine secretion ex vivo by natural killer T cells in HIV-infected individuals is associated with higher CD161 expression

SNYDER-CAPPIONE, Jennifer E.; LOO, Christopher P.; CARVALHO, Karina I.; KUYLENSTIERNA, Carlotta; DEEKS, Steven G.; HECHT, Frederick M.; ROSENBERG, Michael G.; SANDBERG, Johan K.; KALLAS, Esper G.; NIXON, Douglas F.
Fonte: LIPPINCOTT WILLIAMS & WILKINS Publicador: LIPPINCOTT WILLIAMS & WILKINS
Tipo: Artigo de Revista Científica
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Objective: Natural killer T (NKT) cells are efficiently targeted by HIV and severely reduced in numbers in the circulation of infected individuals. The functional capacity of the remaining NKT cells in HIV-infected individuals is poorly characterized. This study measured NKT cell cytokine production directly ex vivo and compared these responses with both the disease status and NKT subset distribution of individual patients. Methods: NKT cell frequencies, subsets, and ex-vivo effector functions were measured in the peripheral blood mononuclear cells of HIV-infected patients and healthy controls by flow cytometry. We measured cytokines from NKT cells after stimulation with either a-galactosyl ceramide-loaded CD1d dimers (DimerX-alpha GalCer) or phorbol myristate acetate and ionomycin. Results: The frequencies of NKT cells secreting interferon-gamma and tumor necrosis factor-alpha were significantly lower in HIV-infected patients than healthy controls after DimerX-alpha GalCer treatment, but responses were similar after treatment with phorbol myristate acetate and ionomycin. The magnitude of the interferon-gamma response to DimerX-alpha GalCer correlated inversely with the number of years of infection. Both interferon-gamma and tumor necrosis factor-alpha production in response to DimerX-alpha GalCer correlated inversely with CD161 expression. Conclusion: The ex-vivo Th1 responses of circulating NKT cells to CD1d-glycolipid complexes are impaired in HIV-infected patients. NKT cell functions may be progressively lost over time in HIV infection...

Benefit of antiretroviral therapy on survival of human immunodeficiency virus-infected patients admitted to an intensive care unit

CRODA, Julio; CRODA, Mariana Garcia; NEVES, Alan; SANTOS, Sigrid De Sousa dos
Fonte: LIPPINCOTT WILLIAMS & WILKINS Publicador: LIPPINCOTT WILLIAMS & WILKINS
Tipo: Artigo de Revista Científica
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Objective: To evaluate the impact of antiretroviral therapy (ART) and the prognostic factors for in-intensive care unit (ICU) and 6-month mortality in human immunodeficiency virus (HIV)-infected patients. Design: A retrospective cohort study was conducted in patients admitted to the ICU from 1996 through 2006. The follow-up period extended for 6 months after ICU admission. Setting: The ICU of a tertiary-care teaching hospital at the Universidade de Sao Paulo, Brazil. Participants: A total of 278 HIV-infected patients admitted to the ICU were selected. We excluded ICU readmissions (37), ICU admissions who stayed less than 24 hours (44), and patients with unavailable medical charts (36). Outcome Measure: In-ICU and 6-month mortality. Main Results: Multivariate logistic regression analysis and Cox proportional hazards models demonstrated that the variables associated with in-ICU and 6-month mortality were sepsis as the cause of admission (odds ratio [OR] = 3.16 [95% confidence interval [CI] 1.65-6.06]); hazards ratio [HR] = 1.37 [95% Cl 1.01-1.88)), an Acute Physiology and Chronic Health Evaluation 11 score >19 [OR = 2.81 (95% CI 1.57-5.04); HR = 2.18 (95% CI 1.62-2.94)], mechanical ventilation during the first 24 hours [OR = 3.92 (95% CI 2.20-6.96); HR = 2.25 (95% CI 1.65-3.07)]...

Targeted Mutagenesis in Pathogenic Leptospira Species: Disruption of the LigB Gene Does Not Affect Virulence in Animal Models of Leptospirosis

CRODA, Julio; FIGUEIRA, Claudio Pereira; WUNDER JR., Elsio A.; SANTOS, Cleiton S.; REIS, Mitermayer G.; KO, Albert I.; PICARDEAU, Mathieu
Fonte: AMER SOC MICROBIOLOGY Publicador: AMER SOC MICROBIOLOGY
Tipo: Artigo de Revista Científica
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The pathogenic mechanisms of Leptospira interrogans, the causal agent of leptospirosis, remain largely unknown. This is mainly due to the lack of tools for genetically manipulating pathogenic Leptospira species. Thus, homologous recombination between introduced DNA and the corresponding chromosomal locus has never been demonstrated for this pathogen. Leptospiral immunoglobulin-like repeat (Lig) proteins were previously identified as putative Leptospira virulence factors. In this study, a ligB mutant was constructed by allelic exchange in L. interrogans; in this mutant a spectinomycin resistance (Spc(r)) gene replaced a portion of the ligB coding sequence. Gene disruption was confirmed by PCR, immunoblot analysis, and immunofluorescence studies. The ligB mutant did not show decrease virulence compared to the wild-type strain in the hamster model of leptospirosis. In addition, inoculation of rats with the ligB mutant induced persistent colonization of the kidneys. Finally, LigB was not required to mediate bacterial adherence to cultured cells. Taken together, our data provide the first evidence of site-directed homologous recombination in pathogenic Leptospira species. Furthermore, our data suggest that LigB does not play a major role in dissemination of the pathogen in the host and in the development of acute disease manifestations or persistent renal colonization.; Fiocruz-Pasteur Scientific Cooperation Agreement; CNPq Brazilian National Research Council[420067/2005]; French Ministry of Research ANR Jeunes Chercheurs[05-JCJC-0105-01]; National Institutes of Health (NIH)[5 R01 AI052473]; National Institutes of Health (NIH)[2 R01 AI034431]; National Institutes of Health (NIH)[2 D43 TW00919]; FAPESP Research Support Foundation of the State of Sao Paulo.[2007/00083-2]

Micro-Positron Emission Tomography in the Evaluation of Trypanosoma cruzi-Induced Heart Disease: Comparison with Other Modalities

PRADO, Cibele M.; FINE, Eugene J.; KOBA, Wade; ZHAO, Dazhi; ROSSI, Marcos A.; TANOWITZ, Herbert B.; JELICKS, Linda A.
Fonte: AMER SOC TROP MED & HYGIENE Publicador: AMER SOC TROP MED & HYGIENE
Tipo: Artigo de Revista Científica
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Noninvasive assessment of cardiac structure and function is essential to understand the natural course of murine infection with Trypanosoma cruzi. Magnetic resonance imaging (MRI) and echocardiography have been used to monitor anatomy and function; positron emission tomography (PET) is ideal for monitoring metabolic events in the myocardium. Mice infected with T. cruzi (Brazil strain) were imaged 15-100 days post infection (dpi). Quantitative (18)F-FDG microPET imaging, MRI and echocardiography were performed and compared. Tracer ((18)F-FDG) uptake was significantly higher in infected mice at all days of infection, from 15 to 100 dpi. Dilatation of the right ventricular chamber was observed by MRI from 30 to 100 dpi in infected mice. Echocardiography revealed significantly reduced ejection fraction by 60 dpi. Combination of these three complementary imaging modalities makes it possible to noninvasively quantify cardiovascular function, morphology, and metabolism from the earliest days of infection through the chronic phase.; NIH[AI076248]; Fogarty International Training (FIRCA/NIH)[D43-TW007129]; FAPESP Fundacao de Amparo a Pesquisa do Estado de Sao Paulo[06/52882-3]; FAPESP Fundacao de Amparo a Pesquisa do Estado de Sao Paulo[06/59618-0]; FAPESP Fundacao de Amparo a Pesquisa do Estado de Sao Paulo[08/00954-6]

A feature selection approach for identification of signature genes from SAGE data

Barrera, Junior ; Cesar, Roberto M; Humes, Carlos ; Martins, David C; Patrão, Diogo FC; Silva, Paulo JS; Brentani, Helena 
Fonte: Biblioteca Digital da Produção Intelectual da USP Publicador: Biblioteca Digital da Produção Intelectual da USP
Tipo: Artigo de Revista Científica
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Abstract Background One goal of gene expression profiling is to identify signature genes that robustly distinguish different types or grades of tumors. Several tumor classifiers based on expression profiling have been proposed using microarray technique. Due to important differences in the probabilistic models of microarray and SAGE technologies, it is important to develop suitable techniques to select specific genes from SAGE measurements. Results A new framework to select specific genes that distinguish different biological states based on the analysis of SAGE data is proposed. The new framework applies the bolstered error for the identification of strong genes that separate the biological states in a feature space defined by the gene expression of a training set. Credibility intervals defined from a probabilistic model of SAGE measurements are used to identify the genes that distinguish the different states with more reliability among all gene groups selected by the strong genes method. A score taking into account the credibility and the bolstered error values in order to rank the groups of considered genes is proposed. Results obtained using SAGE data from gliomas are presented...

Effectiveness of the polysaccharide pneumococcal vaccine among HIV-infected persons in Brazil: a case control study

Veras, Maria ; Enanoria, Wayne TA; Castilho, Euclides A; Reingold, Arthur L
Fonte: Biblioteca Digital da Produção Intelectual da USP Publicador: Biblioteca Digital da Produção Intelectual da USP
Tipo: Artigo de Revista Científica
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Abstract Background Polysaccharide pneumococcal vaccine is recommended for use in HIV-infected adults in Brazil but there is uncertainty about its effectiveness in this patient population. The main objective of this study was to assess the effectiveness of the 23-valent polysaccharide pneumococcal vaccine against invasive pneumococcal infection among HIV-infected adult patients in São Paulo, Brazil. Methods A case-control study of 79 cases and 242 controls matched on CD4+ cell count and health care setting was conducted. Among HIV-infected adults in São Paulo, Brazil, with and without S. pneumoniae recovered from a normally sterile site; prior receipt of 23 valent polysaccharide pneumococcal vaccine was determined by review of medical records and patient interview. Results After adjustment for confounding factors, the point estimate for the effectiveness of 23 valent polysaccharide vaccine among HIV-infected adults against all invasive pneumococcal infection was 18% (95% CI: <0 to 62%). Conclusion We were unable to demonstrate a statistically significant protective effect of 23 valent polysaccharide against invasive pneumococcal infection vaccine among HIV-infected adults in Brazil. While the vaccine is relatively inexpensive and safe...

The presence of a booster phenomenon among contacts of active pulmonary tuberculosis cases: a retrospective cohort

Salles, Cristiane G; Ruffino-Netto, Antonio ; Lapa-e-Silva, Jose R; Kritski, Afranio L; Cailleaux-Cesar, Michelle ; Queiroz-Mello, Fernanda C; Conde, Marcus B
Fonte: Biblioteca Digital da Produção Intelectual da USP Publicador: Biblioteca Digital da Produção Intelectual da USP
Tipo: Artigo de Revista Científica
Português
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Abstract Background Assuming a higher risk of latent tuberculosis (TB) infection in the population of Rio de Janeiro, Brazil, in October of 1998 the TB Control Program of Clementino Fraga Filho Hospital (CFFH) routinely started to recommend a two-step tuberculin skin test (TST) in contacts of pulmonary TB cases in order to distinguish a boosting reaction due to a recall of delayed hypersensitivity previously established by infection with Mycobacterium tuberculosis (M.tb) or BCG vaccination from a tuberculin conversion. The aim of this study was to assess the prevalence of boosted tuberculin skin tests among contacts of individuals with active pulmonary tuberculosis (TB). Methods Retrospective cohort of TB contacts ≥ 12 years old who were evaluated between October 1st, 1998 and October 31st 2001. Contacts with an initial TST ≤ 4 mm were considered negative and had a second TST applied after 7–14 days. Boosting reaction was defined as a second TST ≥ 10 mm with an increase in induration ≥ 6 mm related to the first TST. All contacts with either a positive initial or repeat TST had a chest x-ray to rule out active TB disease...

Broad Cross-Reactive Epitopes of the H5N1 Influenza Virus Identified by Murine Antibodies against the A/Vietnam/1194/2004 Hemagglutinin

Kobayashi-Ishihara, Mie; Takahashi, Hitoshi; Ohnishi, Kazuo; Nishimura, Kengo; Terahara, Kazutaka; Ato, Manabu; Itamura, Shigeyuki; Kageyama, Tsutomu; Tsunetsugu-Yokota, Yasuko
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 19/06/2014 Português
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There is an urgent need for a rapid diagnostic system to detect the H5 subtype of the influenza A virus. We previously developed monoclonal antibodies (mAbs) against the H5 hemagglutinin (HA) for use in a rapid diagnostic kit. In this study, we determined the epitopes of the anti-H5 HA murine mAbs OM-b, AY-2C2, and YH-1A1. Binding assays of the mAbs to different strains of H5 HAs indicated that OM-b and AY-2C2 cross-reacted with HAs from clades 1, 2.1.3.2, 2.2, and 2.3.4, whereas YH-1A1 failed to bind to those of clades 2.1.3.2 and 2.3.4. HA chimeras revealed that the epitopes for each of the mAbs were in the HA1 region. Analysis of escape mutants revealed that OM-b and AY-2C2 mAbs interacted mainly with amino acid residues D43 and G46, and the YH-1A1 mAb interacted with G139 and K or R140 of H5 HA. Multiple alignments of H5 HA protein sequences showed that D43 and G46 were very conserved among H5N1 HAs, except those in clade 2.2.1 and clade 7 (88.7%). The epitope for YH-1A1 mAb was highly variable in the HAs of H5N1, although it was well conserved in those of H5N2-N9. The OM-b and AY-2C2 mAbs could bind to the HAs of clades 1.1 and 2.3.2.1 that are currently epidemic in Asia, and we conclude that these would be effective for the detection of H5N1 infections in this region.

Perfil metabólico de vacas mestiças leiteiras uma semana pré- parto e durante o puerpério fisiológico; Metabolic profile of crossbred cows one week pre-delivery and during physiological puerperium

Oliveira, Raphael Soares de Barros Ramos
Fonte: Universidade Federal de Uberlândia Publicador: Universidade Federal de Uberlândia
Tipo: Dissertação
Português
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Com o intuito de conhecer mais informações sobre o perfil metabólico energético de vacas mestiças leiteiras durante o periparto, foram colhidas amostras sanguíneas de 36 animais, onde para cada tipo de metbolismo dosou-se as concentrações séricas dos senguintes metabólitos: proteínas totais, albumina e globulinas para o perfil protéico; cálcio, fósforo e magnésio para o perfil mineral; AST, ALT, GGT e fosfatase alcalina para a porção enzimática e por fim, ácidos graxos não-esterificados (AGNE), ß-hidroxibutirato (BHB), triglicerídeos, colesterol e as lipoproteínas (VLDL, HDL e LDL) para o perfil energético. As colheitas foram realizadas em sete momentos diferentes (D-7, D0, D7, D14, D21, D28 e D43). Os resultados indicaram hipoproteinemia, tanto pela albumina, quanto pela globulina; o parto demonstrou influência sobre o perfil mineral, especialmente nos valores do cálcio, no qual pode-se notar situações de hipocalcemia subclínica, uma vez que nenhum animal apresentou sintomas clínicos para esse transtorno. As concentrações enzimáticas, não representaram nenhuma alteração significativa, apenas a AST, durante períodos próximos ao parto, apresentou aumento na sua concentração. Por fim, não foi verificada alterações significativas que indicassem deficiência energética acentuada...

Estudio del mezclado de emulsiones concentradas de aceite en agua aplicando la metodología de superficie de respuesta

DI SCIPIO,SABRINA; ESCALONA,YESSICA; QUIJADA,KARINA; MILLÁN,FÉLIX
Fonte: Universidad Central de Venezuela Publicador: Universidad Central de Venezuela
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2008 Português
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En la industria alimentaria se producen con frecuencia emulsiones con alto contenido de fase dispersa (> 75%), considerando parámetros físico-químicos, de composición y las condiciones de mezclado. La mayoría de las investigaciones relacionadas con el mezclado de sistemas dispersos han estudiado sistemas diluidos y sin surfactante. El presente trabajo analiza la preparación de emulsiones concentradas de aceite de maíz en agua utilizando un surfactante no iónico etoxilado. El método experimental se basó en un diseño factorial 2³ con puntos centrales y axiales, variando: velocidad de rotación del impulsor, tiempo de mezclado y proporción aceite:agua. Se evaluó la influencia de estas variables sobre el promedio aritmético de la distribución de volumen y de área de las gotas de la emulsión, d43 y d32, respectivamente. Mediante el análisis de varianza del espacio experimental, eliminando los efectos no significativos, se determinó que el d43 puede ser predicho casi en un 99% por un modelo cuadrático, a diferencia de la superficie de respuesta del d32 que no puede ser explicada en toda su extensión, porque la falta de ajuste es apreciable; sin embargo, dicho modelo pudo ser usado para analizar la influencia de las variables. Se realizó un ajuste cúbico para el d32. Este modelo presentó términos confundidos que impidieron determinar una relación final entre las variables puras y cruzadas...