Publications by authors named "Aya Sadahiro"

Leishmaniasis, a disease caused by protozoan spp., exhibits a broad range of clinical manifestations. Host resistance or susceptibility to infections is often influenced by the genetic make-up associated with natural immunity.

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Inflammation is a physiological mechanism of the immune response and has an important role in maintaining the hematopoietic cell niche in the bone marrow. During this process, the participation of molecules produced by innate immunity cells in response to a variety of pathogen-associated molecular patterns and damage-associated molecular patterns is observed. However, chronic inflammation is intrinsically associated with leukemogenesis, as it induces DNA damage in hematopoietic stem cells and contributes to the creation of the preleukemic clone.

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  • - The study investigates heteroresistance in the C. neoformans/C. gattii complex, specifically looking at resistance to fluconazole in isolates from Amazonas, Brazil, revealing varying susceptibility levels in clinical and environmental samples.
  • - A total of 45 isolates were analyzed, showing that clinical C. gattii isolates had significantly higher minimal inhibitory concentrations (MICs) compared to environmental strains, with all isolates exhibiting some degree of heteroresistance.
  • - The results indicated that many isolates can adapt to higher fluconazole concentrations over time, suggesting that current antifungal susceptibility tests may need reevaluation to better understand their implications for treatment and patient outcomes in cryptococcosis cases.
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  • Host genetics play a crucial role in determining an individual's resistance or susceptibility to active pulmonary tuberculosis (TB).
  • A specific genetic variant, rs10818488 in the TRAF1/C5 gene, is linked to a higher risk of developing TB, with a significant association found in multibacillary cases leading to increased bacterial load in the lungs.
  • The study indicates that a "loss-of-function" variant in TRAF1/C5 may lower the production of TNF-α, thereby increasing susceptibility to TB and affecting the clinical severity of the disease.
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Hepatitis C is considered a major public health problem caused by the hepatitis C virus (HCV). Viral infections are known to induce production of IL1β through the signaling pathway of inflammasomes. Emerging evidences suggest that Inflammasome genes may influence the immune response against HCV as the host genetic background may contribute to the balance between acute and chronic inflammation.

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  • - A study investigated the link between inflammasome genes and childhood leukemia by comparing 158 patients with acute lymphoblastic leukemia (ALL) to 192 healthy controls.
  • - Genetic analysis revealed that the IL1B C/T rs19644 variant increased the risk of developing ALL, while the NLRP1 A/T rs12150220 variant appeared to provide some protection against infections.
  • - No significant associations were found for NLRP3 and P2RX7 variants, indicating that more research with larger groups is needed to confirm the role of these genetic variants in childhood leukemia.
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  • * The study investigated single-nucleotide variants (SNVs) in specific inflammasome genes in patients with pulmonary TB (PTB), extrapulmonary TB (EPTB), and healthy controls to understand their role in immune responses.
  • * Results showed that SNV rs1103577 may offer protection against PTB, while rs1692816 reduces the risk for EPTB, highlighting the need for further investigation into their impact on immune responses, especially concerning IL
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We investigated the in vitro effects of two antigens on monocyte-derived dendritic cells (moDCs) from patients with paracoccidioidomycosis (PCM). MoDCs from patients with active or treated PCM and non-PCM subjects were generated, stimulated with TNF-α, and antigens, 43 kDa glycoprotein (gp43) and cell-free antigen (CFA), and analyzed by flow cytometry and enzyme-linked immunosorbent assays (ELISA). Our data revealed that patients with PCM had a high frequency of HLA-DR cells, but the treated group had more CD86 cells with increased IL-12p40.

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  • * A specific genetic variant, rs10754558, protects against TB by enhancing the immune response through the NLRP3 inflammasome, which plays a crucial role in how the body reacts to different strains of Mtb.
  • * The study reveals that loss-of-function variants are linked to extra-pulmonary TB, and the activation levels of the inflammasome can differentiate between TB patients and healthy individuals in endemic areas, highlighting genetic and immune responses in TB susceptibility.
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Paracoccidioidomycosis (PCM) is an important endemic, systemic disease in Latin America caused by spp. This mycosis has been associated with high morbidity and sequels, and its clinical manifestations depend on the virulence of the infecting strain, the degree and type of immune response, infected tissues, and intrinsic characteristics of the host. The T helper(Th)1 and Th17/Th22 cells are related to resistance and control of infection, and a Th2/Th9 response is associated with disease susceptibility.

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Tuberculosis (TB), caused by mycobacterial species of the complex, is a serious global health issue. Brazil is among the 22 countries with the highest number of TB cases, and the state of Amazonas has the highest incidence of TB cases in the country. Toll-like receptors (TLRs) are important pattern recognition receptors of the innate immunity and play a key role in orchestrating an effective immune response.

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Mansonellosis is an endemic disease in the South and Central America. In Brazil, one of the etiological agents is Mansonella ozzardi. This filarial infection is yet poorly understood, with a controversial morbity, presenting since a oligosymptoms, malaria-like signs or without complaint in humans.

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Siglec-1/CD169 is a sialoadhesin expressed by macrophages thought to function in cell-to-cell interactions. In the lung, the expression of Siglec-1 is specific for alveolar macrophages and single nucleotide polymorphisms (SNPs) in SIGLEC1 have been recently associated with asthma severity. Taking in account the role of alveolar macrophages in the control of M.

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Immunogenetic host factors are associated with susceptibility or protection to tuberculosis (TB). Strong associations of HLA class II genes with TB are reported. We analyzed the HLA-DRB1*04 alleles to identify subtypes associated with pulmonary TB and their interaction with risk factors such as alcohol, smoking, and gender in 316 pulmonary TB patients and 306 healthy individuals from the Brazilian Amazon.

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We investigated the association between hepatitis C virus (HCV) genotypes and host cytokine gene polymorphisms and serum cytokine levels in patients with chronic hepatitis C. Serum IL-6, TNF-α, IL-2, IFN-γ, IL-4, IL-10, and IL-17A levels were measured in 67 HCV patients (68.2% genotype 1 [G1]) and 47 healthy controls.

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Background: Recent studies have shown that the inflammatory process, including the biomarker production, and the intense activation of innate immune responses are greater in the malaria caused by Plasmodium vivax than other species. Here, we examined the levels of serum biomarkers and their interaction during acute malaria.

Material And Methods: Blood samples were collected from P.

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Previous studies identified the functional polymorphism 1858C/T in the gene PTPN22 in association with several autoimmune diseases and with resistance to tuberculosis (TB). This study is the first to investigate the association between pulmonary TB and the PTPN22 1858C/T polymorphism in the Brazilian Amazon. We conducted a case-control study involving a group of 413 individuals, comprised of 208TB carriers and 205 controls.

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Purpose: The aim of this study was to investigate the influence of the TNF -308 G/A polymorphism in the promoter region of the tumor necrosis factor-α gene on the susceptibility and severity of rheumatoid arthritis (RA) in individuals from the Brazilian Amazon.

Methods: A total of 323 individuals-192 healthy controls without arthritis and 131 individuals suffering from arthritis-were genotyped for this polymorphism using a methodology based on PCR-RFLP.

Results: The frequency of the A allele (TNF2) in rheumatoid arthritis sufferers was not significantly higher than in the controls (p=0.

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Background: Rheumatoid Arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the joints that affects approximately 1% of the population worldwide. The HLA-DRB1 gene locus plays a major role in genetic susceptibility to RA, a condition that has been associated with a high cardiovascular morbidity and mortality in many studies.

Methodology/principal Findings: The aim of this work was to investigate which types of HLA class II genes are associated with RA in patients from the Brazilian Amazon and their influence on high cardiovascular risk status in this population.

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Article Synopsis
  • The study investigated dermatophytosis in children under 12 in Amazonas, Brazil, between March 1996 and November 2005, focusing on its frequency and causes.
  • Out of 590 samples analyzed, 210 tested positive, with tinea capitis being the most common type, primarily caused by Trichophyton tonsurans.
  • Other forms of dermatophytosis identified included tinea corporis, tinea pedis, and tinea cruris, with T. rubrum also implicated in several cases.
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We analyzed the kinetics of cytokine production by mononuclear cells from 17 patients who had been treated for paracoccidioidomycosis, using the stimulus of gp43 peptide groups (43 kDa glycoprotein of Paracoccidioides brasiliensis) at 0.1 and 1 microM, gp43 (1 microg/ml) and crude Paracoccidioides brasiliensis antigen (PbAg; 75 microg/ml). IFN-gamma production was a maximum at 144 hours in relation to the G2 and G8 peptide groups at 1 microM and was greatest at 144 hours when stimulated by gp43 and by PbAg.

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Vaccines with synthetic peptides induce the immune response to epitopes that bind to several HLA alleles. By using a TEPITOPE algorithm, we selected and analyzed the T-cell responses of peripheral blood mononuclear cells from 29 paracoccidioidomycosis (PCM) patients to peptides of the immunodominant gp43 antigen of Paracoccidioides brasiliensis, the causative agent of PCM.

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Human leukocyte antigen (HLA) class II alleles are involved in antigen processing and in the presentation of antigens to T lymphocytes. Few studies have investigated HLA genes in paracoccidioidomycosis. In the present investigation, we analyzed the distribution of the HLA class II alleles DRB1 and DQB1 in 45 healthy volunteers and in 80 patients with paracoccidioidomycosis.

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