RESUMO
Serological tests used for the diagnosis of tegumentary leishmaniasis (TL) presents problems, mainly related to their variable sensitivity and/or specificity, which can be caused by low levels of antileishmanial antibodies or by presence of cross-reactive diseases, respectively. In this context, the search for new antigenic candidates presenting higher sensitivity and specificity is urgently required. In the present study, the amino acid sequences of the LiHyT, LiHyD, LiHyV, and LiHyP proteins, which were previously showed to be antigenic in the visceral leishmaniasis (VL), were evaluated and eight B-cell epitopes were predicted and used for construction of gene codifying a chimeric protein called ChimLeish. The protein was expressed, purified and evaluated as a recombinant antigen in ELISA (Enzyme-Linked Immunosorbent Assay) for the diagnosis of TL. The own B cell epitopes used to construct the chimera were synthetized and also evaluated as antigens, as well as a soluble Leishmania braziliensis antigenic extract (SLA). Results showed that ChimLeish presented 100% sensitivity and specificity to diagnose TL, while synthetic peptides showed sensitivity varying from 9.1% to 90.9%, while specificity reached from 98.3% to 99.1%. SLA showed sensitivity and specificity of 18.2% and 98.3%, respectively. A preliminary prognostic evaluation showed that anti-ChimLeish IgG antibodies declined in significant levels, when serological reactivity was compared before and six months after treatment, suggesting also a possible prognostic role of this antigen for TL.
Assuntos
Leishmania , Leishmaniose , Anticorpos Antiprotozoários , Antígenos de Protozoários/genética , Ensaio de Imunoadsorção Enzimática , Epitopos de Linfócito B/genética , Humanos , Leishmania/genética , Proteínas Recombinantes de Fusão/genética , Sensibilidade e Especificidade , Testes SorológicosRESUMO
The diagnosis of leishmaniasis presents problems due to the variable sensitivity and/or specificity of tests. In addition, high levels of anti-parasite antibodies can remain after treatment, making it difficult to conduct a prognostic follow-up of patients. In this context, it is necessary to identify new candidates to be examined for the sensitive and specific diagnosis of the disease. In the present study, four Leishmania proteins, previously shown as antigenic for tegumentary leishmaniasis (TL), were evaluated, and their linear specific B-cell epitopes were predicted and used to generate a new gene codifying chimeric protein called ChimB, which was cloned, and the recombinant version was expressed, purified, and evaluated in ELISA (Enzyme-Linked Immunosorbent Assay) to diagnose TL and visceral leishmaniasis (VL). A total of 220 human serum samples were used, and, when ChimB was used, results showed sensitivity, specificity, and positive and negative predictive values of 100% for the diagnosis of both diseases; however, when using peptides, the sensitivity values reached from 28.0% to 57.3% and specificity varied from 16.3% to 83.7%. A soluble Leishmania extract (SLA) showed sensitivity and specificity values of 30.7% and 45.9%, respectively. The area under the curve (AUC) value for ChimB was 1.0, while for synthetic peptides, this value reached between 0.502 and 0.635, whereas for SLA, the value was of 0.589. Serological assays using sera samples collected before and after treatment showed significant reductions in the anti-ChimB antibody levels after therapy, suggesting a prognostic role of this recombinant antigen. In conclusion, preliminary data suggest the use from ChimB as a potential candidate for the diagnosis and prognosis of leishmaniasis.
Assuntos
Leishmania , Leishmaniose Visceral , Leishmaniose , Animais , Anticorpos Antiprotozoários , Antígenos de Protozoários/genética , Ensaio de Imunoadsorção Enzimática/métodos , Epitopos de Linfócito B/genética , Humanos , Leishmaniose/diagnóstico , Leishmaniose Visceral/diagnóstico , Peptídeos , Proteínas Recombinantes de Fusão/genética , Sensibilidade e Especificidade , Testes Sorológicos/métodosRESUMO
The diagnosis of visceral leishmaniasis (VL) has improved with the search of novel antigens; however, their performance is limited when samples from VL/human immunodeficiency virus (HIV)-coinfected patients are tested. In this context, studies conducted to identify more suitable antigens to detect both VL and VL/HIC coinfection cases should be performed. In the current study, phage display was performed using serum samples from healthy subjects and VL, HIV-infected and VL/HIV-coinfected patients; aiming to identify novel phage-exposed epitopes to be evaluated with this diagnostic purpose. Nine non-repetitive and valid sequences were identified, synthetized and tested as peptides in enzyme-linked immunosorbent assay experiments. Results showed that three (Pep2, Pep3 and Pep4) peptides showed excellent performance to diagnose VL and VL/HIV coinfection, with 100% sensitivity and specificity values. The other peptides showed sensitivity varying from 50.9 to 80.0%, as well as specificity ranging from 60.0 to 95.6%. Pep2, Pep3 and Pep4 also showed a potential prognostic effect, since specific serological reactivity was significantly decreased after patient treatment. Bioinformatics assays indicated that Leishmania trypanothione reductase protein was predicted to contain these three conformational epitopes. In conclusion, data suggest that Pep2, Pep3 and Pep4 could be tested for the diagnosis of VL and VL/HIV coinfection.
Assuntos
Bacteriófagos , Coinfecção , Infecções por HIV , Leishmaniose Visceral , Coinfecção/diagnóstico , Epitopos , HIV , Infecções por HIV/diagnóstico , Humanos , Leishmaniose Visceral/diagnósticoRESUMO
Visceral leishmaniasis (VL) is a neglected tropical disease of global importance caused by parasites of the genus Leishmania, and coinfection with human immunodeficiency virus (HIV) is common in countries where both diseases are endemic. In particular, widely used immunological tests for VL diagnosis have impaired sensitivity (Se) and specificity (Sp) in VL/HIV coinfected patients and there is also cross-reactivity with other endemic diseases, e.g., Chagas disease, malaria, and tuberculosis. To develop new antigens to improve the diagnosis of VL and VL/HIV coinfection, we predicted eight specific B-cell epitopes of four Leishmania infantum antigens and constructed a recombinant polypeptide chimera antigen called ChimLeish. A serological panel of 195 serum samples was used to compare the diagnostic capabilities of ChimLeish alongside the individual synthetic peptides. ChimLeish reacted with sera from all VL and VL/HIV coinfected patients [Se = 100%; Sp = 100%; area under the curve (AUC) = 1.0]. Peptides showed lower reactivities (Se = 76.8 to 99.2%; Sp = 67.1 to 95.7%; AUC between 0.87 and 0.98) as did a L. infantum antigenic preparation used as an antigen control (Se = 56.8%; Sp = 69.5%: AUC = 0.45). Notably, ChimLeish demonstrated a significant reduction (p < 0.05) of anti-ChimLeish antibodies after treatment and cure of a small number of patients. Although only a limited serological panel was tested, preliminary data suggest that ChimLeish should be evaluated in larger sample studies for the diagnosis of VL and VL/HIV coinfection.
Assuntos
Coinfecção , Infecções por HIV , Leishmania infantum , Leishmaniose Visceral , Antígenos de Protozoários/genética , Coinfecção/diagnóstico , HIV/genética , Infecções por HIV/complicações , Humanos , Leishmaniose Visceral/diagnóstico , Prognóstico , Proteínas Recombinantes de FusãoRESUMO
Porcine rotavirus (RV) is a major viral agent associated with severe diarrhea in newborn piglets. RVA, RVB, RVC, and RVH are RV species that have already been identified in pigs. RVA is considered the most prevalent and relevant virus in pig production worldwide. This study aimed to evaluate the frequency of RV infection associated with diarrhea in suckling piglets from regular RVA-vaccinated Brazilian pig herds between 2015 and 2021. Therefore, 511 diarrheic fecal samples were collected from suckling piglets aged up to 3 weeks from 112 pig farms located in three main Brazilian pork production regions. All piglets were born to RVA-vaccinated sows. The nucleic acids of RVA, RVC, and RVH were investigated by RT-PCR assays and RVB by semi-nested RT-PCR assay. Of the diarrheic fecal samples analyzed, 221/511 (43.3%) were positive for at least one of the RV species. Regarding the distribution of RV species among the positive fecal samples that presented with only one RV species, 99 (44.8%), 63 (28.5%), and 45 (20.4%) were identified as RVB, RVC, and RVA, respectively. RVH was not identified in diarrheic piglets with a single infection. More than one RV species was identified in 14/221 (6.3%) of the diarrheic fecal samples evaluated. Co-detection of RVB + RVH (11/221; 5.0%), RVA + RVB (1/221; 0.4%), RVA + RVC (1/221; 0.4%), and RVB + RVC (1/221; 0.4%) was identified in fecal samples. The results demonstrated a significant increase in the RVC and, mainly, RVB detection rates in single infections. This study allowed us to characterize the importance of other RV species, in addition to RVA, in the etiology of neonatal diarrhea in piglets from pig herds with a regular vaccination program for RVA diarrhea control and prophylaxis.
Assuntos
Infecções por Rotavirus , Rotavirus , Doenças dos Suínos , Vírus , Animais , Suínos , Feminino , Doenças dos Suínos/diagnóstico , Rotavirus/genética , Diarreia/veterinária , Fezes , Filogenia , Vacinação , GenótipoRESUMO
CONTEXT: Pregnant women have physiological metabolic changes in glycemic and lipid profiles that are essential for fetal development. OBJECTIVE: The aim of this systematic review was to analyze the effects of fish-oil-capsule supplementation on the glycemic and lipid profiles of pregnant women. DATA SOURCES: A systematic search was conducted of the MEDLINE (by PubMed), Embase, Cochrane Library (CENTRAL) databases and gray literature, including preprints for all relevant studies published in English, with no date restrictions. DATA EXTRACTION: The estimated pooled results were analyzed using a random-effects model and represented by mean differences (MDs) and corresponding 95% confidence intervals (CIs). The analyses were performed with R software, version 4.2.1, using the "Meta" packages, versions 6.0-0. DATA ANALYSIS: Fifteen eligible studies were included after screening. In a pooled analysis, overall fish-oil supplementation had no effect on parameters compared with placebo. In the subgroup analysis, fish-oil supplementation may be beneficial in insulin (MD: -2.11 IU/mL; 95% CI: -3.86, -0.36) and homeostasis model assessment of insulin resistance (HOMA-IR) (MD: -0.71; 95% CI: -1.14, -0.29) indices, with heterogeneity (I2 =0%) among pregnant women with diabetes mellitus. In the subgroup with doses of eicosapentaenoic acid (EPA) below 200 mg, there was a reduction in HOMA-IR in the intervention group (MD: -0.60; 95% CI: -1.14, -0.06). CONCLUSION: Pregnant women taking fish-oil capsules showed significant beneficial changes in the subgroups of type 2 diabetes and EPA dosages below 200 mg for insulin and HOMA-IR.
RESUMO
Living with extremely low-income is an important risk factor for HIV/AIDS and can be mitigated by conditional cash transfers. Using a cohort of 22.7 million low-income individuals during 9 years, we evaluated the effects of the world's largest conditional cash transfer, the Programa Bolsa Família, on HIV/AIDS-related outcomes. Exposure to Programa Bolsa Família was associated with reduced AIDS incidence by 41% (RR:0.59; 95%CI:0.57-0.61), mortality by 39% (RR:0.61; 95%CI:0.57-0.64), and case fatality rates by 25% (RR:0.75; 95%CI:0.66-0.85) in the cohort, and Programa Bolsa Família effects were considerably stronger among individuals of extremely low-income [reduction of 55% for incidence (RR:0.45, 95% CI:0.42-0.47), 54% mortality (RR:0.46, 95% CI:0.42-0.49), and 37% case-fatality (RR:0.63, 95% CI:0.51 -0.76)], decreasing gradually until having no effect in individuals with higher incomes. Similar effects were observed on HIV notification. Programa Bolsa Família impact was also stronger among women and adolescents. Several sensitivity and triangulation analyses demonstrated the robustness of the results. Conditional cash transfers can significantly reduce AIDS morbidity and mortality in extremely vulnerable populations and should be considered an essential intervention to achieve AIDS-related sustainable development goals by 2030.
Assuntos
Síndrome da Imunodeficiência Adquirida , População da América do Sul , Adolescente , Humanos , Feminino , Estudos de Coortes , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Renda , Pobreza , Brasil/epidemiologiaRESUMO
Background: Social determinants of health (SDH) include factors such as income, education, and race, that could significantly affect the human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AIDS). Studies on the effects of SDH on HIV/AIDS are limited, and do not yet provide a systematic understanding of how the various SDH act on important indicators of HIV/AIDS progression. We aimed to evaluate the effects of SDH on AIDS morbidity and mortality. Methods: A retrospective cohort of 28.3 million individuals was evaluated over a 9-year period (from 2007 to 2015). Multivariable Poisson regression, with a hierarchical approach, was used to estimate the effects of SDH-at the individual and familial level-on AIDS incidence, mortality, and case-fatality rates. Findings: A total of 28,318,532 individuals, representing the low-income Brazilian population, were assessed, who had a mean age of 36.18 (SD: 16.96) years, 52.69% (14,920,049) were female, 57.52% (15,360,569) were pardos, 34.13% (9,113,222) were white/Asian, 7.77% (2,075,977) were black, and 0.58% (154,146) were indigenous. Specific socioeconomic, household, and geographic factors were significantly associated with AIDS-related outcomes. Less wealth was strongly associated with a higher AIDS incidence (rate ratios-RR: 1.55; 95% confidence interval-CI: 1.43-1.68) and mortality (RR: 1.99; 95% CI: 1.70-2.34). Lower educational attainment was also greatly associated with higher AIDS incidence (RR: 1.46; 95% CI: 1.26-1.68), mortality (RR: 2.76; 95% CI: 1.99-3.82) and case-fatality rates (RR: 2.30; 95% CI: 1.31-4.01). Being black was associated with a higher AIDS incidence (RR: 1.53; 95% CI: 1.45-1.61), mortality (RR: 1.69; 95% CI: 1.57-1.83) and case-fatality rates (RR: 1.16; 95% CI: 1.03-1.32). Overall, also considering the other SDH, individuals experiencing greater levels of socioeconomic deprivation were, by far, more likely to acquire AIDS, and to die from it. Interpretation: In the population studied, SDH related to poverty and social vulnerability are strongly associated with a higher burden of HIV/AIDS, most notably less wealth, illiteracy, and being black. In the absence of relevant social protection policies, the current worldwide increase in poverty and inequalities-due to the consequences of the COVID-19 pandemic, and the effects of war in the Ukraine-could reverse progress made in the fight against HIV/AIDS in low- and middle-income countries (LMIC). Funding: National Institute of Allergy and Infectious Diseases (NAIDS), National Institutes of Health (NIH), US Grant Number: 1R01AI152938.
RESUMO
BACKGROUND: One of the biggest challenges of the response to the AIDS epidemic is to reach the poorest people. In 2004, Brazil implemented one of the world's largest conditional cash transfer programmes, the Bolsa Família Programme (BFP). We aimed to evaluate the effect of BFP coverage on AIDS incidence, hospitalisations, and mortality in Brazil. METHODS: In this longitudinal ecological study, we developed a conceptual framework linking key mechanisms of BFP effects on AIDS indicators and used ecological panel data from 5507 Brazilian municipalities over the period of 2004-18. We used government sources to calculate municipal-level AIDS incidence, hospitalisation, and mortality rates, and used multivariable regressions analyses of panel data with fixed-effects negative binomial models to estimate the effect of BFP coverage, which was classified as low (0-29%), intermediate (30-69%), and high (≥70%), on AIDS indicators, while adjusting for all relevant demographic, socioeconomic, and health-care covariates at the municipal level. FINDINGS: Between 2004 and 2018, in the municipalities under study, 601â977 new cases of AIDS were notified, of which 376â772 (62·6%) were in males older than 14 years, 212â465 (35·3%) were in females older than 14 years, and 12â740 (2·1%) were in children aged 14 years or younger. 533â624 HIV/AIDS-related hospitalisations, and 176â868 AIDS-related deaths had been notified. High BFP coverage was associated with reductions in incidence rate ratios of 5·1% (95% CI 0·9-9·1) for AIDS incidence, 14·3% (7·7-20·5) for HIV/AIDS hospitalisations, and 12·0% (5·2-18·4) for AIDS mortality. The effect of the BFP on AIDS indicators was more pronounced in municipalities with higher AIDS endemicity levels, with reductions in incidence rate ratios of 12·7% (95% CI 5·4-19·4) for AIDS incidence, 21·1% (10·7-30·2) for HIV/AIDS hospitalisations, and 14·7% (3·2-24·9) for AIDS-related mortality, and reductions in AIDS incidence of 14·6% (5·9-22·5) in females older than 14 years, 9·7% (1·4-17·3) in males older than 14 years, and 24·5% (0·5-42·7) in children aged 14 years or younger. INTERPRETATION: The effect of BFP coverage on AIDS indicators in Brazil could be explained by the reduction of households' poverty and by BFP health-related conditionalities. The protection of the most vulnerable populations through conditional cash transfers could contribute to the reduction of AIDS burden in low-income and middle-income countries. FUNDING: US National Institute of Allergy and Infectious Diseases, National Institutes of Health. TRANSLATION: For the Portugese translation of the abstract see Supplementary Materials section.
Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Criança , Feminino , Humanos , Masculino , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Brasil/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Hospitalização , IncidênciaRESUMO
Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) to detect SARS-CoV-2 RNA is an essential test to monitor the occurrence of COVID-19. A methodology is proposed for the determination of maximum pool size and adjustments of cut-off values of cycle threshold (Ct in RT-qPCR pool testing, to compensate for the dilution caused by pooling. The trade-off between pool size and test sensitivity is stated explicitly. The procedure was designed to ensure that samples that would be detectable in individual testing remain detectable in pool testing. The proposed relaxation in cut-off is dependent on the pool size, allowing a relatively tight correction to avoid loss of detection of positive samples. The methodology was evaluated in a study of pool testing of adults attending a public emergency care unit, reference for COVID-19 in Belo Horizonte, Brazil, and presenting flu-like symptoms. Even samples on the edge of detectability in individual testing were detected correctly. The proposed procedure enhances the consistency of RT-qPCR pool testing by enforcing that the scales of detectability in pool processing and in individual sample processing are compatible. This may enhance the contribution of pool testing to large-scale testing for COVID-19.
Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , SARS-CoV-2/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/diagnóstico , Teste de Ácido Nucleico para COVID-19/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real/normas , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/fisiologia , Adulto JovemRESUMO
Laboratory diagnosis of leishmaniasis shows variable efficacy in detecting infected mammalian hosts and there is a need to identify suitable antigens to improve the accuracy of diagnostic tests. In the present study, a L. infantum hypothetical protein called LiHyQ was evaluated for the diagnosis of tegumentary (TL) and visceral (VL) leishmaniasis using canine and human samples. A collection of dog sera (n=155) were tested and contained samples from asymptomatic (n=20) and symptomatic (n=25) VL animals, from healthy dogs living in endemic (n=25) or non-endemic (n=25) areas of disease, from Leish-Tec® vaccinated dogs (n=20) or from dogs infected with Ehrlichia canis (n=15), Babesia canis (n=10) and Trypanosoma cruzi (n=15). Sensitivity (Se), Specificity (Sp), Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of 100% were observed for rLiHyQ with these samples, whereas the Se, Sp, PPV and NPV values with L. infantum Soluble Leishmania Antigen (SLA) preparation were 60.0%, 99.0%, 96.0% and 86.0%, respectively. A collection of human sera (n=305) were tested and contained samples from TL (n=50) and VL (n=40) patients, from VL/HIV co-infected patients (n=35), from patients infected with HIV alone (n=30), Chagas Disease (n=30), malaria (n=10), tuberculosis (n=10), paracoccidioidomycosis (n=15), leprosy (n=30) or aspergillosis (n=15); and from healthy subjects (n=40). Se, Sp, PPV and NPV values of 100% were observed for rLiHyQ with these samples, whereas the Se, Sp, PPV and NPV values with SLA were 58.0%, 76.0%, 50.0% and 82.0%, respectively. The antibody reactivity against the protein was compared with commercial kits, and the kappa index varied from 0.95 to 1.00 for rLiHyQ, and of 0.55 to 0.82 for the kits. In addition, the serological follow-up of treated patients showed a significant reduction in rLiHyQ-specific IgG antibody levels. All canine and human samples were tested at the same time using the same reagents, in order to reduce experimental variation and interference in data interpretation. In conclusion, our preliminary data suggest a diagnostic and prognostic role for rLiHyQ against leishmaniasis.