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1.
PLoS Negl Trop Dis ; 17(6): e0011416, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37276232

RESUMEN

Nucleotide-binding oligomerization domain, leucine-rich repeat-containing protein family (NLR) are intracellular pathogen recognition receptors mediating innate immunity, releasing proinflammatory cytokines IL-1ß and IL-18, and promoting pyroptotic cell death, upon sensing pathogenic or endogenous danger signals. In animal models, NLRP3 inflammasome has a dual role, pathogenic or protective in Leishmania-infection, depending on the Leishmania species and mice strain. Caspase recruitment containing domain 8 (CARD8) is a negative regulator of NLRP3 inflammasome and also an inhibitor of transcription factor NFĸB, a major transcription factor of proinflammatory cytokines. We investigated whether single nucleotide variants in CARD8 may partially explain why only a proportion of individuals coming from the same area of endemicity of leishmaniasis develop cutaneous leishmaniasis caused by Leishmania guyanensis. We genotyped four single nucleotide variants of the CARD8 gene by direct nucleotide sequencing in 1741 individuals from an endemic area of leishmaniasis, constituting 850 patients with CL and 891 healthy controls. The frequencies of the genotypes of the variants rs2288877 T>C, rs73944113 C>T, and rs2043211 A>T are similar among the patients with CL and HC, while the variant rs2288876 A>G) reveals an excess of the genotype AA among the patients with CL (44%) compared to 37% in the HC group. Allele A of the variant rs2288876 A>G) is associated with susceptibility to CL (OR = 1.2 [95%CI 1.03-1.4]; P = 0.01). Haplotype analysis showed that individuals harboring the haplotype CCAA have 280% odds of developing CL caused by L. guyanensis (OR = 3.8 [95% CI 2.0-7.7]; p = 0.00004). The variants rs2288877 T>C and rs2288876 A>G correlate with the plasma level of IL-8. Spearman correlation showed a significant positive correlation between the rs2288876 A>G allele A and the level of IL-8 (ρ = 0.22; p = 0.0002). CARD8 may partially contribute to the development of CL caused by L. guyanensis.


Asunto(s)
Proteínas Adaptadoras de Señalización CARD , Leishmania guyanensis , Leishmaniasis Cutánea , Citocinas/genética , Predisposición Genética a la Enfermedad , Genotipo , Inflamasomas/genética , Interleucina-8 , Leishmania guyanensis/genética , Leishmaniasis Cutánea/genética , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Polimorfismo de Nucleótido Simple , Factor de Necrosis Tumoral alfa/genética , Proteínas Adaptadoras de Señalización CARD/genética , Proteínas Adaptadoras de Señalización CARD/metabolismo , Humanos
3.
Front Immunol ; 13: 974051, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36091007

RESUMEN

The immunopathology associated with Leishmaniasis is a consequence of inflammation. Upon infection with Leishmania, the type of host-immune response is determinant for the clinical manifestations that can lead to either self-healing or chronic disease. Multiple pathways may determine disease severity. A comparison of systemic immune profiles in patients with cutaneous leishmaniasis caused by L. guyanensis and healthy individuals with the same socio-epidemiological characteristics coming from the same endemic areas as the patients is performed to identify particular immune profile and pathways associated with the progression of disease development. Twenty-seven plasma soluble circulating factors were evaluated between the groups by univariate and multivariate analysis. The following biomarkers pairs IL-17/IL-9 (ρ=0,829), IL-17/IL-12 (ρ=0,786), IL-6/IL-1ra (ρ=0,785), IL-6/IL-12 (ρ=0,780), IL-1ß/G-CSF (ρ=0,758) and IL-17/MIP-1ß (ρ=0,754) showed the highest correlation mean among the patient while only INF-γ/IL-4 (ρ=0.740), 17/MIP-1ß (ρ=0,712) and IL-17/IL-9 (ρ=0,707) exhibited positive correlation among the control group. The cytokine IL-17 and IL1ß presented the greater number of positive pair correlation among the patients. The linear combinations of biomarkers displayed IP-10, IL-2 and RANTES as the variables with the higher discriminatory activity in the patient group compared to PDGF, IL-1ra and eotaxin among the control subjects. IP-10, IL-2, IL-1ß, RANTES and IL-17 seem to be predictive value of progression to the development of disease among the Lg-infected individuals.


Asunto(s)
Leishmania guyanensis , Leishmaniasis Cutánea , Biomarcadores , Quimiocina CCL4 , Quimiocina CCL5 , Quimiocina CXCL10 , Citocinas , Humanos , Proteína Antagonista del Receptor de Interleucina 1 , Interleucina-12 , Interleucina-17 , Interleucina-2 , Interleucina-6 , Interleucina-9
4.
J Infect Dis ; 225(1): 163-171, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34139757

RESUMEN

BACKGROUND: Emerging evidence suggests that the interleukin (IL) 17/ IL-23 axis may play a role in the pathogenesis of leishmaniasis. Our aim was to investigate whether the IL-23R variant rs11805303 is a risk factor for the development of cutaneous leishmaniasis (CL) in Leishmania guyanensis-infected individuals. METHODS: We genotyped by polymerase chain reaction-restriction fragment length polymorphism the rs11805303 C/T in 828 patients with CL and 806 healthy individuals. Plasma tumor necrosis factor-α, IL-6, interferon-γ, IL-1ß, and IL-17 were measured with the Bioplex assay. RESULTS: The distribution of the genotypes differed between patients with CL and healthy controls with a common odds ratio of 1.78 (P = 2.2 × 10-11) for the disease-associated T allele. Leishmania guyanensis-infected individuals homozygous for the T allele show a 200% increased risk of progressing to disease development, with a 95% confidence interval ranging from 81% to 400% (P = 9.9 × 10-6) in comparison to individuals homozygous for the C allele. Males homozygous for the T allele have higher plasma levels of IL-17 compared with heterozygous or homozygous CC individuals. CONCLUSIONS: The present association of the IL-23R variant rs11805303 with the development of CL suggests that the IL-17/IL-23 axis may play an important role in the pathogenesis of CL.


Asunto(s)
Interleucina-17/sangre , Interleucina-23/genética , Leishmania guyanensis/genética , Leishmaniasis Cutánea/diagnóstico , Estudios de Casos y Controles , Humanos , Interleucina-23/sangre , Leishmania guyanensis/aislamiento & purificación , Leishmaniasis Cutánea/genética , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo de Nucleótido Simple , Receptores de Interleucina
5.
PLoS Negl Trop Dis ; 15(9): e0009795, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34543271

RESUMEN

Leishmania are intracellular protozoan parasites that cause a wide spectrum of clinical manifestations in genetically susceptible individuals with an insufficient or balanced Th1 immune response to eliminate the parasite. MiRNAs play important regulatory role in numerous biological processes including essential cellular functions. miR146-a acts as an inhibitor of interleukin 1 receptor associated kinase 1 (IRAK1) and tumour necrosis factor (TNF) receptor associated factor 6 (TRAF6) present in the toll-like receptors pathway while miR499a modulates TGF-ß and TNF signalling pathways. Here, we investigated whether MIRNA146A rs2910164 and MIRNA499 rs3746444 variants are associated with the development of L. guyanensis (Lg)-cutaneous leishmaniasis (CL). The variants MIR146A rs2910164 and MIR499A rs3746444 were assessed in 850 patients with Lg-CL and 891 healthy controls by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Plasma cytokines were measured using the BioPlex assay. Carriers of rs2910164 CC genotype have 30% higher odds of developing CL (ORadjage/sex = 1.3 [95%CI 0.9-1.8]; Padjage/sex 0.14) compared to individuals with the genotype GG (ORadjage/sex = 0.77 [95%CI 0.56-1.0]; Padjage/sex 0.14) if exposed to Lg-infection. Heterozygous GC individuals also showed lower odds of developing CL (ORadjage/sex = 0.77 [95%CI 0.5-1.1]; Padjage/sex 0.09). Homozygosity for the allele C is suggestive of an association with the development of Lg-CL among exposed individuals to Lg-infection. However, the odds of developing CL associated with the CC genotype was evident only in male individuals (ORadjage = 1.3 [95% CI = 0.9-2.0]; Padjage = 0.06). Individuals homozygous for the G allele tend to have higher plasma IL-8 and CCL5. Similarly, for the MIR499A rs3746444, an association with the G allele was only observed among male individuals (OR = 1.4 [1.0-1.9]; P = 0.009). In a dominant model, individuals with the G allele (GG-GA) when compared to the AA genotype reveals that carriers of the G allele have 40% elevated odds of developing Lg-CL (ORadjage = 1.4 [1.1-1.9]). Individuals with the GG genotype have higher odds of developing Lg-CL (ORadjage/sex = 2.0 [95%CI 0.83-5.0]; Padjage = 0.01. Individuals homozygous for the G allele have higher plasma IL-8. Genetic combinations of both variants revealed that male individuals exposed to Lg bearing three or four susceptible alleles have higher odds of developing Lg-CL (OR = 2.3 [95% CI 1.0-4.7]; p = 0.017). Both MIR146A rs2910164 and MIR499A rs3746444 are associated with the development of Lg-CL and this association is prevalent in male individuals.


Asunto(s)
Interleucina-8/metabolismo , Leishmania guyanensis , Leishmaniasis Cutánea/genética , MicroARNs/genética , Adulto , Alelos , Citocinas/sangre , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Quinasas Asociadas a Receptores de Interleucina-1 , Interleucina-8/sangre , Péptidos y Proteínas de Señalización Intracelular , Masculino , Persona de Mediana Edad , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo de Nucleótido Simple
6.
Rev. Soc. Bras. Med. Trop ; 48(supl.1): 12-19, 2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-748358

RESUMEN

This study evaluated the occurrence of American tegumentary leishmaniasis (ATL) in the State of Amazonas, Brazil, in the last 30 years with emphasis on the last 10 years (2001 to 2010). The disease was predominantly observed in males (76.2%), in the 21- to 30-year-old age group (26.6%) and in extractive workers (43.7%); 3.3% of the cases were the mucosal form. The endemic channel shows the disease seasonality, with a predominance of cases at the beginning and end of each year. The number of cases by municipality in the period of 2001-2010 shows the maintenance of the endemic in the localities where the highest numbers of cases have always been registered, namely, Manaus, Rio Preto da Eva, Itacoatiara and Presidente Figueiredo. The comparison of data from 2001 to 2005 and from 2006 to 2010 showed the emergence of this disease in municipalities that had been previously unaffected. In the last years, there has been a significant increase in the activities of control, diagnosis and treatment of leishmaniasis in the State of Amazonas. In conclusion, the historical series of ATL analyzed in this study suggests that the transmission foci remain and are even expanding, though without continuous transmission in the intra- or peridomicile settings. Moreover, the disease will persist in the Amazon while the factors associated with infection acquisition relative to forest exploitation continue to have economic appeal. There is a real expectation of wide variations in disease incidence that can be influenced by climate and economic aspects.


Asunto(s)
Animales , Femenino , Masculino , Gastrópodos/genética , Estadios del Ciclo de Vida/genética , Conducta Sexual Animal , Procesos de Determinación del Sexo/genética , Fertilización , Variación Genética , Genética de Población , Genotipo , Repeticiones de Microsatélite/genética , Paternidad , Caracteres Sexuales
7.
Rev. Soc. Bras. Med. Trop ; 48(supl.1): 79-86, 2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-748364

RESUMEN

INTRODUCTION: In the State of Amazonas, particularly in the capital Manaus, meningitis has affected populations of different cultures and social strata over the years. Bacterial meningitis is caused by several different species and represents a major issue of public health importance. The present study reports the meningitis case numbers with different etiologies in Amazonas from January 1976 to December 2012. METHODS: Since the 1970s, the (currently named) Tropical Medicine Foundation of Doutor Heitor Vieira Dourado [Fundação de Medicina Tropical Doutor Heitor Vieira Dourado (FMT-HVD)] has remained a reference center in Amazonas for the treatment of meningitis through the diagnosis and notification of cases and the confirmation of such cases using specific laboratory tests. RESULTS: The foundation has achieved coverage of over 90% of the state medical records for many years. Between 1990 and 2012, meningitis cases caused by Haemophilus influenzae decreased with the introduction of the H. influenzae vaccine. Meningococcal disease previously had a higher frequency of serogroup B disease, but starting in 2008, the detection of serogroup C increased gradually and has outpaced the detection of serogroup B. Recently, surveillance has improved the etiological definition of viral meningitis at FMT-HVD, with enteroviruses, Epstein-Barr virus (EBV) and varicella zoster virus (VZV) prevailing in this group of pathogens. With the advent of acquired immunodeficiency syndrome (AIDS), cryptococcal meningitis has become an important disease in Amazonas. Additionally, infectious meningitis is an important burden in the State of Amazonas. CONCLUSIONS: Changes in the epidemiological profile for the different etiology-defined cases are the result of continuous epidemiological surveillance and laboratory capacity improvements and control measures, such as Haemophilus influenzae vaccination. .


Asunto(s)
Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Adulto Joven , Meningitis Bacterianas/epidemiología , Meningitis Viral/epidemiología , Distribución por Edad , Brasil/epidemiología , Incidencia
8.
Rev. Soc. Bras. Med. Trop ; 41(6): 658-663, Nov.-Dec. 2008. graf, tab
Artículo en Portugués | LILACS | ID: lil-502050

RESUMEN

A biodiversidade da Região Amazônica inclui diversas espécies de vetores artrópodes em seus diferentes ecótopos, possibilitando o surgimento de doenças como malária, filarioses e arboviroses. De agosto de 2001 a julho de 2002, realizou-se coletas de culicídeos no domicílio, peridomicílio e nas matas da Comunidade São João, área rural de Manaus, Amazonas. Foram capturados 1.240 culicídeos, pertencentes às subfamílias Culicinae (99 por cento) e Anophelinae (1 por cento), somando 50 espécies. O predomínio entre as tribos foi nitidamente de Culicini, com 904 (72,9 por cento) exemplares, destacando-se as espécies Culex usquatus (22,6 por cento) e Culex quinquefasciatus (17,7 por cento). Do total de culicídeos, 1.077 (86,9 por cento) exemplares foram capturados no interior das matas, 101 (8,1 por cento) no peridomicílio e 62 (5 por cento) no intradomicílio. O ecótopo com maior diversidade de espécies foi a mata. Assinalou-se a presença de Anopheles darlingi, Anopheles triannulatus, Aedes aegypti, Haemagogus janthinomys e outros vetores comprovados ou potenciais.


The biodiversity of the Amazon region includes many species of arthropod vectors in different ecotopes, thus enabling occurrences of diseases like malaria, filariasis and arbovirosis. From August 2001 to July 2002, we gathered culicids from inside homes, from areas surrounding these homes and from forested areas of the São João Community, in the rural zone of Manaus, State of Amazonas. 1240 specimens were collected, belonging to the Culicinae (99 percent) and Anophelinae (1 percent) subfamilies, with 50 species. The Culicini tribe clearly predominated, with 904 specimens (72.9 percent), and the species Culex usquatus (22.6 percent) and Culex quinquefasciatus (17.7 percent) were prominent. Out of the total number of culicids, 1,077 (86.9 percent) were caught in the forests, 101 (8.1 percent) in the areas surrounding homes and 62 (5 percent) inside homes. Forests were the ecotope that presented the highest species diversity. The presence of Anopheles darlingi, Anopheles triannulatus, Aedes aegypti, Haemagogus janthinomys and other proven or potential vectors was recorded.


Asunto(s)
Animales , Femenino , Masculino , Culicidae/clasificación , Insectos Vectores/clasificación , Biodiversidad , Brasil , Densidad de Población , Población Rural
9.
Acta amaz ; 37(1): 133-137, 2007. ilus, graf, tab
Artículo en Portugués | LILACS | ID: lil-459262

RESUMEN

Os autores descrevem o resultado de dois anos de investigação de um foco de Leishmaniose Tegumentar Americana (LTA), ocorrida em área urbanizada em um conjunto habitacional na cidade da Manaus-AM. Chama atenção o fato de que este não é o padrão de ocorrência de surtos da doença na região, e sim interrupção da transmissão após urbanização. Foram investigados os animais considerados reservatórios em potencial para a leishmaniose em domicílios humanos e em áreas de floresta adjacentes. Foram testados anticorpos contra Leishmania spp em amostras de sangue de cães e detectada reatividade pela reação de imunofluorescencia indireta em oito (20,51 por cento) dos examinados. Entre os animais silvestres examinados a espécie Didelphis marsupialis foi predominante, com 20 exemplares capturados, sendo encontrados homoflagelados em três destes e lesões suspeitas de leishmaniose cutanea em dois. Acredita-se que um assentamento populacional desordenado ocorrido nas adjacências tenha causado o deslocamento das populações de vetores e reservatórios naturais em direção às casas do conjunto Hiléia propiciando o surto.


This is the result of a two year follow-up of a Cutaneous Leishmaniasis (CL) foci in the Hileia urban neighborhood in Manaus. It is important to point out that this is not the usual pattern of Leishmaniasis occurrence in this area. The authors investigated the animal potential reservoir in households and in the surrounding forest area. Samples were tested for leishmaniasis antibodies by RIFI. Eight (20.51 percent) of the examined domestic dogs showed reactivity. In captured wild animals, the Didelphis marsupialis was predominant in twenty specimens, three with homoflagelated in the blood and two with suspicious cutaneous lesions. We believe that the disordered population growth in the nearby area pushed the population of vectors and natural reservoir toward the homes in the Heleia neighborhood creating conditions for this outbreak.


Asunto(s)
Leishmaniasis Cutánea , Animales Domésticos
10.
Rev. Soc. Bras. Med. Trop ; 37(6): 476-479, nov.-dez. 2004. graf
Artículo en Portugués | LILACS | ID: lil-390703

RESUMEN

Em 1998, a Fundação de Medicina Tropical/Instituto de Medicina Tropical do Amazonas implementou o sistema de vigilância para síndromes febris agudas indiferenciadas, com o propósito de manter vigilância ativa e passiva na Amazônia Ocidental, Brasil, permitindo identificar e diagnosticar os agentes etiológicos causadores de febres agudas. O diagnóstico foi realizado através de estudos sorológicos para a detecção de anticorpos IgM, utilizando-se técnicas de ELISA (Enzyme-linked-immunosorbent assay) e kits ELISA comerciais. Foram analisadas 8.557 amostras de soros de pacientes com suspeita clínica de dengue, 40 por cento dos soros foram ELISA positivos para o vírus da dengue e 26 por cento dos soros foram ELISA positivos para outras doenças exantemáticas virais como rubéola, sarampo, parvovírus, oropouche e mayaro.


Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Adulto , Persona de Mediana Edad , Dengue , Virus del Dengue , Brotes de Enfermedades , Exantema , Anticuerpos Antivirales , Brasil , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina M , Estaciones del Año
11.
Rev. saúde pública ; 37(5): 674-675, out. 2003. mapas
Artículo en Portugués | LILACS | ID: lil-348061

RESUMEN

A partir de exemplares de Aedes albopictus coletados em área urbana no município de Manaus, AM, Brasil, e das informações sobre a presença desse mosquito em vários municípios do Estado do Amazonas, registra-se pela primeira vez a introduçäo dessa espécie nesse Estado.


Asunto(s)
Circuncisión Masculina , Infecciones por VIH/transmisión , África , Infecciones por VIH/prevención & control
12.
Rev. Soc. Bras. Med. Trop ; 36(3): 343-348, maio-jun. 2003. mapas, tab, graf
Artículo en Portugués | LILACS | ID: lil-341058

RESUMEN

Em 1996, foi realizado um levantamento da fauna de Culicidae (coleta de adultos e imaturos) em cinco dos dez municípios onde foram registrados 14 casos de febre amarela silvestre (Rio Preto da Eva, Iranduba, Manacapuru, Manaquiri e Careiro). Os mosquitos foram coletados utilizando-se armadilhas de luz CDC, inspeções domiciliares e captura com tubos coletores para isca humana. Foram identificadas entre adultos e imaturos 36 espécies de Culicidae, entre estas, nove foram encontradas apenas na fase imatura. Dentre os adultos, coletou-se espécies de Haemagogus janthinomys, Ha. leucocelaenus e Aedes fulvus, incluídas entre os vetores de febre amarela silvestre


Asunto(s)
Animales , Humanos , Culicidae , Insectos Vectores , Fiebre Amarilla , Brasil
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