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1.
Immunol Invest ; 53(5): 752-765, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38634569

RESUMEN

BACKGROUND: The process of tissue injury in coronary artery disease (CAD) has been associated with activation of the complement system, partly due to the action of mannose-binding lectin (MBL) and C3, which are expressed in atherosclerotic lesions. OBJECTIVE: The aim of this study was to evaluate the serum levels of MBL and C3 in patients with CAD and to compare them with healthy controls. Additionally, we aim to assess the correlation between MBL and C3 levels and cardiometabolic parameters. METHODS: MBL and C3 serum concentration were determined by ELISA and immunoturbidimetry, respectively, in up to 119 patients undergoing coronary angiography for CAD evaluation, comprising 48 individuals diagnosed with acute myocardial infarction (MI) and 71 without MI. A total of 93 paired healthy controls were included in the study. RESULTS: Individuals with CAD had MBL serum concentration higher than controls (p = .002), regardless of the presence of MI (p = .006). In addition, high concentration of MBL (>2000 ng/mL) was more frequent in patients with CAD (p = .007; OR = 2.6; 95% CI = 1.3-5.1). C3 levels were not significantly associated with any of the patient groups but were positively correlated with cardiometabolic parameters such as body mass index (BMI) and triglycerides levels. CONCLUSIONS: Higher concentrations of MBL were found to be associated with CAD, whereas C3 levels were found to be associated with cardiovascular risk factors.


Asunto(s)
Complemento C3 , Enfermedad de la Arteria Coronaria , Lectina de Unión a Manosa , Humanos , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico , Lectina de Unión a Manosa/sangre , Masculino , Femenino , Persona de Mediana Edad , Estudios Transversales , Complemento C3/metabolismo , Complemento C3/análisis , Anciano , Angiografía Coronaria , Infarto del Miocardio/sangre , Infarto del Miocardio/diagnóstico , Biomarcadores/sangre , Índice de Masa Corporal , Estudios de Casos y Controles
2.
Life Sci ; 282: 119793, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34242658

RESUMEN

Visceral leishmaniasis (VL) is a neglected and highly lethal disease. VL is endemic in South American countries, with Brazil being responsible for 96% of the cases. In this continent, VL is caused by the protozoan Leishmania (Leishmania) infantum (L. infantum), transmitted by the bite of infected female phlebotomine sandflies. Immediately after the inoculation of L.infantum promastigotes into the vertebrate host, the complement, as part of the first line of innate response, becomes activated. L. infantum promastigotes glycocalyx is rich in carbohydrates that can activate the lectin pathway of complement system. In this study, we evaluated whether the lectin pathway collectins [manose binding lectin (MBL) and collectin-11 (CL-11)] and ficolins (-1, -2 and -3) interact with L.infantum promastigotes, using confocal microscopy and flow cytometry. The binding of MBL, CL-11 and ficolins -1 and -3, but not ficolin-2, was observed on the surface of live metacyclic promastigotes after incubation with normal human serum (NHS) or recombinant proteins. C3 and C4 deposition as well as complement mediated lyses was also demonstrated after interaction with NHS. These results highlight a role for collectins and ficolins in the initial immune response to L.infantum.


Asunto(s)
Proteínas del Sistema Complemento/inmunología , Lectinas/inmunología , Leishmania infantum/inmunología , Leishmaniasis Visceral/inmunología , Activación de Complemento , Interacciones Huésped-Parásitos , Humanos , Leishmania infantum/fisiología
3.
Dev Comp Immunol ; 120: 104061, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33667529

RESUMEN

Visceral Leishmaniasis is an infectious disease that affects mainly humans and dogs, with the latter being important reservoirs of the parasite. Conversely, cats are naturally resistant. The immune system can offer important explanation to this problematic as there is no evidence on the role that the complement system plays in cats. In this context, effect of the complement system from human, dog and cat sera on Leishmania infantum was evaluated. Activation of the classical, alternative and lectin pathways was assessed through hemolytic and ELISA assays. Lytic activity of the complement on the parasite's viability was investigated by Transmission Electron Microscopy and Flow Cytometry. Complement proteins were more consumed in dog serum on the classical and alternative pathways, leading to less hemolytic activity, and only in cat serum they were consumed on the lectin pathway when incubated with L. infantum. Lytic activity on the parasite's surface was more accentuated in human serum, and varied throughout the parasite's developmental stages.


Asunto(s)
Enfermedades de los Gatos/inmunología , Enfermedades de los Perros/inmunología , Leishmania infantum/inmunología , Leishmaniasis Visceral/inmunología , Animales , Enfermedades de los Gatos/sangre , Enfermedades de los Gatos/parasitología , Gatos , Vía Alternativa del Complemento/inmunología , Vía Clásica del Complemento/inmunología , Proteínas del Sistema Complemento/inmunología , Proteínas del Sistema Complemento/metabolismo , Enfermedades de los Perros/sangre , Enfermedades de los Perros/parasitología , Perros , Voluntarios Sanos , Hemólisis/inmunología , Humanos , Leishmaniasis Visceral/sangre , Leishmaniasis Visceral/parasitología , Leishmaniasis Visceral/veterinaria , Especificidad de la Especie
4.
Pract Lab Med ; 23: e00197, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33364284

RESUMEN

BACKGROUND: Chronic inflammatory diseases lead to glycation of protein, lipids and nuclear acids. One product generated in this context is pentosidine. AIM: To study pentosidine levels in Systemic Lupus Erythematosus (SLE) and its possible association with disease activity and cumulative damage. METHODS: Pentosidine serum levels were measured in the serum by ELISA commercial kits in 79 patients with SLE. Disease activity index and cumulative damage were studied by SELENA-SLEDAI (Safety of Estrogen in Lupus National Assessment Systemic Lupus Erythematosus Disease Activity Index) and cumulative damage by SLICC/ACR DI (Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage index for Systemic Lupus Erythematosus) respectively and simultaneously with determination of pentosidine levels. Epidemiological and clinical and serological profile were collected from the charts. RESULTS: In the 79 studied patients, the SLEDAI ranged from 0 to 12 (median of 0) and the SLICC/ACR-DI from 0 to 4 (median of 0). Serum pentosidine levels did not correlate with SLEDAI neither with SLICC. Patients with discoid skin lesions and photosensitivity had lower levels than those without them, with p â€‹= â€‹0.04 in both. CONCLUSION: In SLE, serum pentosidine levels did not reflect activity and cumulative damage. Patients with skin manifestations had lower levels of this biomarker.

5.
Acta Trop ; 212: 105673, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32827454

RESUMEN

Leishmania (Viannia) braziliensis is the main agent of mucocutaneous Leishmaniasis, a neglected tropical disease that affects thousands of people in Brazil. It has been shown that complement plays a critical role at early stages of Leishmania infection and that is involved in the invasion of macrophages by the promastigotes. Ficolins and collectins are soluble pattern recognition and triggering molecules of the lectin complement pathway. We investigated here whether lectin pathway activators ficolin-1, ficolin-2, ficolin-3 and CL-11 bind to live L. braziliensis promastigotes in vitro. Promastigote forms in the stationary growth phase were incubated with normal human serum (NHS) or recombinant ficolins 1, 2 and 3, MBL and CL-11, and protein binding was evaluated by confocal microscopy and flow cytometry. Ficolins 1, 2 and 3, MBL and CL-11 were able to bind to the surface of live promastigotes after incubation with either NHS or recombinant proteins. A partial inhibition by N-acetyl-d-glucosamine characterizing the participation of acetylated groups in the deposition of ficolins and CL-11 to glycoconjugates on the surface of L. braziliensis was observed. These evidences highlight a role for the lectin pathway in the innate response to L. braziliensis.


Asunto(s)
Colectinas/fisiología , Lectinas/fisiología , Leishmania braziliensis/inmunología , Proteínas del Sistema Complemento/fisiología , Humanos , Inmunidad Innata , Ficolinas
6.
J Clin Endocrinol Metab ; 105(2)2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31587051

RESUMEN

CONTEXT: Type 2 diabetes mellitus (T2DM) is associated with an increased risk of fractures. No study has evaluated the correlation of bone histomorphometry (BH) parameters with glycemic control and presence of chronic complications (CCs) in premenopausal women with T2DM. OBJECTIVES: To evaluate BH and correlate them with the degree of glycemic control and presence of CCs. DESIGN, SETTINGS, AND PATIENTS: This was a cross-sectional study conducted at a tertiary medical center. Twenty-six premenopausal women with T2DM were divided into groups with glycated hemoglobin HbA1c < 7% (good control, GC; n = 10) and HbA1c > 7% (poor control, PC; n = 16), and further subdivided into groups with (n = 9) and without (n = 17) CCs. BH parameters (bone volume [bone volume per total volume, BV/TV], trabecular thickness [Tb.Th], trabecular number [Tb.N], trabecular separation [Tb.Sp], osteoid thickness [O.Th], osteoid surface [osteoid surface per bone surface, OS/BS]), mineralizing surface [MS/BS], bone formation rate [BFR]), mineral apposition rate [MAR]) as well as serum pentosidine (PEN) and insulin-like growth factor (IGF)-1 were measured. The BH data were compared among the groups and with a BH control group (control group, CG, n = 15) matched by age, sex, and race. RESULTS: BV/TV was increased in GC (P < .001) and PC (P = .05) groups and O.th (P = .03) was smaller in the PC group than in the CG. A comparison of the groups with and without CCs with the CG showed in the group with CCs, O.Th was smaller(P = .01) and BV/TV similar to the CG (P = .11). HbA1c correlated negatively with O.Th (P = .02) and OS/BS (P = .01). There was no correlation of BH to PEN and IGF-1. CONCLUSION: BH in premenopausal patients with T2DM is affected by disease control and chronic complications.


Asunto(s)
Desarrollo Óseo , Enfermedades Óseas/etiología , Diabetes Mellitus Tipo 2/fisiopatología , Adulto , Arginina/análogos & derivados , Arginina/sangre , Glucemia/análisis , Hueso Esponjoso/fisiopatología , Enfermedad Crónica , Estudios Transversales , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Hemoglobina Glucada/análisis , Humanos , Factor I del Crecimiento Similar a la Insulina/análisis , Lisina/análogos & derivados , Lisina/sangre , Masculino
7.
J Microbiol Methods ; 140: 61-66, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28669799

RESUMEN

Sepsis is the leading cause of death in intensive care units (ICUs) worldwide and its diagnosis remains a challenge. Blood culturing is the gold standard technique for blood stream infection (BSI) identification. Molecular tests to detect pathogens in whole blood enable early use of antimicrobials and affect clinical outcomes. Here, using real-time PCR, we evaluated DNA extraction using seven manual and three automated commercially available systems with whole blood samples artificially contaminated with Escherichia coli, Staphylococcus aureus, and Candida albicans, microorganisms commonly associated with BSI. Overall, the commercial kits evaluated presented several technical limitations including long turnaround time and low DNA yield and purity. The performance of the kits was comparable for detection of high microorganism loads (106CFU/mL). However, the detection of lower concentrations was variable, despite the addition of pre-processing treatment to kits without such steps. Of the evaluated kits, the UMD-Universal CE IVD kit generated a higher quantity of DNA with greater nucleic acid purity and afforded the detection of the lowest microbial load in the samples. The inclusion of pre-processing steps with the kit seems to be critical for the detection of microorganism DNA directly from whole blood. In conclusion, future application of molecular techniques will require overcoming major challenges such as the detection of low levels of microorganism nucleic acids amidst the large quantity of human DNA present in samples or differences in the cellular structures of etiological agents that can also prevent high-quality DNA yields.


Asunto(s)
Sangre/microbiología , ADN Bacteriano/aislamiento & purificación , ADN de Hongos/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Sepsis/diagnóstico , Donantes de Sangre , Candida albicans/genética , Candidiasis/diagnóstico , Candidiasis/microbiología , ADN Bacteriano/genética , ADN de Hongos/genética , Escherichia coli/genética , Infecciones por Escherichia coli/diagnóstico , Infecciones por Escherichia coli/microbiología , Humanos , Juego de Reactivos para Diagnóstico , Sepsis/microbiología , Infecciones Estafilocócicas/sangre , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/genética , Staphylococcus aureus/aislamiento & purificación
8.
Front Microbiol ; 8: 607, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28473804

RESUMEN

Trypanosoma cruzi is a protozoan parasite known to cause Chagas disease (CD), a neglected sickness that affects around 6-8 million people worldwide. Originally, CD was mainly found in Latin America but more recently, it has been spread to countries in North America, Asia, and Europe due the international migration from endemic areas. Thus, at present CD represents an important concern of global public health. Most of individuals that are infected by T. cruzi may remain in asymptomatic form all lifelong, but up to 40% of them will develop cardiomyopathy, digestive mega syndromes, or both. The interaction between the T. cruzi infective forms and host-related immune factors represents a key point for a better understanding of the physiopathology of CD. In this context, the complement, as one of the first line of host defense against infection was shown to play an important role in recognizing T. cruzi metacyclic trypomastigotes and in controlling parasite invasion. The complement consists of at least 35 or more plasma proteins and cell surface receptors/regulators, which can be activated by three pathways: classical (CP), lectin (LP), and alternative (AP). The CP and LP are mainly initiated by immune complexes or pathogen-associated molecular patterns (PAMPs), respectively, whereas AP is spontaneously activated by hydrolysis of C3. Once activated, several relevant complement functions are generated which include opsonization and phagocytosis of particles or microorganisms and cell lysis. An important step during T. cruzi infection is when intracellular trypomastigotes are release to bloodstream where they may be target by complement. Nevertheless, the parasite uses a sequence of events in order to escape from complement-mediated lysis. In fact, several T. cruzi molecules are known to interfere in the initiation of all three pathways and in the assembly of C3 convertase, a key step in the activation of complement. Moreover, T. cruzi promotes secretion of plasma membrane-derived vesicles from host cells, which prevent the activity of C3 convertase C4b2a and thereby may hinder complement. In this review, we aim to present an overview on the strategies used by T. cruzi in order to circumvent the activation of complement and, consequently, its biological effects.

9.
Rev. bras. anal. clin ; 41(3): 221-222, 2009.
Artículo en Portugués | LILACS | ID: lil-544446

RESUMEN

Neste trabalho investigou-se a prevalencia das infeccoes pelos virus HIV, HTLV e pelo Treponema pallidum em uma populacao indigena Kaingang (150 individuos) e mestica (64 individuos) da reserva de Mangueirinha, no Estado do Parana, Brasil. Osresultados demonstraram ausencia de positividade para HIV 1/2, HTLV 1/2 e Sifilis nos individuos investigados.


This study investigated the prevalence of HIV, HTLV and Treponema pallidum infections in 150 Kaingang Indians andin 64 individuals of mixed race Kaingang with non Indians from the Mangueirinha reservation in the state of Paraná, Brazil. The results showed that none of the individuals was positive for HIV 1/2, HTLV 1/2 and Syphilis.


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Niño , Adolescente , Adulto , Persona de Mediana Edad , Anciano de 80 o más Años , Infecciones por Deltaretrovirus , VIH , Indio , Estudios Seroepidemiológicos , Sífilis
10.
Arq Gastroenterol ; 44(2): 156-61, 2007.
Artículo en Portugués | MEDLINE | ID: mdl-17962863

RESUMEN

BACKGROUND: Celiac disease is the most common intestinal disorder of caucasian populations and presents a prevalence of 8% to 18% between the relatives of patients. The anti-endomysial (IgA-EmA) and anti-tissue transglutaminase antibodies (IgA-tTG) have represented an important non invasive and sensitivity method of screening and diagnosis of celiac disease in risk groups and populations. AIM: To investigate the prevalence of IgA-EmA and IgA-tTG antibodies in relatives of celiac patients and verify the degree of concordance between them. METHODS: One hundred and seventy seven relatives of celiac patients (76(feminino); 101(masculino); 2-79 years) and 93 healthy individuals were evaluated (34(feminino); 59(masculino); 2-71 years). IgA-EmA were detected by indirect immunofluorescence, with human umbilical cord as substrate, while anti-IgA-tTG titers were measured by enzyme-linked immunosorbent assay (ELISA), using commercial kit. RESULTS: Total positivity to antibodies in relatives of celiac patients was of 21% (37/177), and showed significant difference compared to control group (0%; 0/93). Twelve percent (21/177) of celiac disease relatives were positive to IgA-EmA, 13.56% (24/177) to IgA-tTG, and 4.52% (8/177) to both assays simultaneously. The concordance between both methods was 83.6% (148/177) and the discordance was 16.4% (29/177), with a positive and significant correlation (r = 0.435). Among the concordant results, 79.1% (140/177) were negative and 4.52% (8/177) were positive to both antibodies. Among the discordant results, 7.34% (13/177) were positive to IgA-EmA and negative to IgA-tTG, while 9.04% (16/177) were negative to IgA- EmA and positive to IgA-tTG. CONCLUSION: Although the high positivity to IgA-EmA and IgA-tTG emphasizes the importance of the serological screening in relatives of celiac patients, the discordances detected in this study showed that the use of only one method can lead to false negative results. Consequently these relatives will not be submitted to intestinal biopsy to confirm the diagnosis of celiac disease, and to the correct and earlier treatment.


Asunto(s)
Autoanticuerpos/sangre , Enfermedad Celíaca/diagnóstico , Inmunoglobulina A/sangre , Transglutaminasas/sangre , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Niño , Preescolar , Ensayo de Inmunoadsorción Enzimática , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Inmunoglobulina A/inmunología , Masculino , Persona de Mediana Edad , Transglutaminasas/inmunología
11.
Arq. gastroenterol ; 44(2): 156-161, abr.-jun. 2007. graf
Artículo en Portugués | LILACS | ID: lil-465718

RESUMEN

RACIONAL: A doença celíaca representa, na atualidade, a doença intestinal mais comum em populações caucasóides e apresenta prevalência que varia de 8 por cento a 18 por cento nos familiares dos pacientes. A pesquisa dos anticorpos anti-endomísio (EmA-IgA) e antitransglutaminase tecidual (anti-tTG-IgA) constitui importante recurso não-invasivo e sensível de triagem e diagnóstico da doença celíaca em grupos de risco e populações. OBJETIVO: Avaliar a prevalência do EmA e anti-tTG em um grupo de familiares de celíacos e verificar o grau de concordância entre os dois métodos. MÉTODOS: Foram estudados 177 familiares (76(feminino); 101(masculino); 2-79 anos) e 93 indivíduos voluntßrios e sadios (34 (feminino); 59 (masculino); 2-71 anos) como grupo controle. O EmA foi detectado por imunofluorescência indireta (substrato: cordão umbilical humano) e o anti-tTG pelo método de ELISA (kit comercial). RESULTADOS: A positividade total de anticorpos nos familiares em estudo foi de 21 por cento (37/177), mostrando significativa diferença em relação aos controles (0 por cento; 0/93). Doze por cento (21/177) dos familiares foram positivos para o EmA e 13,56 por cento (24/177) para o anti-tTG, sendo 4,52 por cento (8/177) positivos concomitantemente para os dois anticorpos. A concordância de resultados entre os dois métodos foi de 83,6 por cento (148/177) e a discordância de 16,4 por cento (29/177), caracterizando uma correlação positiva significante (r= 0.435) entre ambos. Dentre os concordantes, 79,1 por cento (140/177) eram negativos para o anti-tTG e EmA, e 4,52 por cento (8/177) positivos para ambos. Nos casos discordantes, 7,34 por cento (13/177) apresentaram EmA positivo e anti-tTG negativo e 9,04 por cento (16/177) eram anti-tTG positivo e EmA negativo. CONCLUSÃO: Embora a alta positividade obtida para o EmA e anti-tTG destaque a importância da triagem sorológica em familiares de pacientes com doença celíaca, as discordâncias detectadas no estudo...


BACKGROUND: Celiac disease is the most common intestinal disorder of caucasian populations and presents a prevalence of 8 percent to 18 percent between the relatives of patients. The anti-endomysial (IgA-EmA) and anti-tissue transglutaminase antibodies (IgA-tTG) have represented an important non invasive and sensitivity method of screening and diagnosis of celiac disease in risk groups and populations. AIM: To investigate the prevalence of IgA-EmA and IgA-tTG antibodies in relatives of celiac patients and verify the degree of concordance between them. METHODS: One hundred and seventy seven relatives of celiac patients (76(feminino); 101(masculino); 2-79 years) and 93 healthy individuals were evaluated (34(feminino); 59(masculino); 2-71 years). IgA-EmA were detected by indirect immunofluorescence, with human umbilical cord as substrate, while anti-IgA-tTG titers were measured by enzyme-linked immunosorbent assay (ELISA), using commercial kit. RESULTS: Total positivity to antibodies in relatives of celiac patients was of 21 percent (37/177), and showed significant difference compared to control group (0 percent; 0/93). Twelve percent (21/177) of celiac disease relatives were positive to IgA-EmA, 13.56 percent (24/177) to IgA-tTG, and 4.52 percent (8/177) to both assays simultaneously. The concordance between both methods was 83.6 percent (148/177) and the discordance was 16.4 percent (29/177), with a positive and significant correlation (r = 0.435). Among the concordant results, 79.1 percent (140/177) were negative and 4.52 percent (8/177) were positive to both antibodies. Among the discordant results, 7.34 percent (13/177) were positive to IgA-EmA and negative to IgA-tTG, while 9.04 percent (16/177) were negative to IgA- EmA and positive to IgA-tTG. CONCLUSION: Although the high positivity to IgA-EmA and IgA-tTG emphasizes the importance of the serological screening in relatives of celiac patients, the discordances detected in this study...


Asunto(s)
Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Autoanticuerpos/sangre , Enfermedad Celíaca/diagnóstico , Inmunoglobulina A/sangre , Transglutaminasas/sangre , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente Indirecta , Inmunoglobulina A/inmunología , Transglutaminasas/inmunología
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