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1.
Euro Surveill ; 29(17)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38666402

RESUMO

In January 2024, a child was diagnosed with measles in a paediatric hospital in Lisbon. Of 123 contacts, 39 (32%) were not fully immunised, presenting a risk for a potential outbreak. The public health unit initiated control measures and identified challenges during the response, such as the lack of interoperability between information systems and accessing vaccination records. The lessons learned prompted changes to national contact tracing procedures for measles, further strengthening Portugal's preparedness.


Assuntos
Busca de Comunicante , Surtos de Doenças , Hospitais Pediátricos , Sarampo , Humanos , Sarampo/prevenção & controle , Sarampo/epidemiologia , Portugal/epidemiologia , Surtos de Doenças/prevenção & controle , Masculino , Criança , Pré-Escolar , Feminino , Saúde Pública , Vacinação , Lactente , Adolescente
2.
PLoS Pathog ; 17(11): e1010067, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34784389

RESUMO

Human ascariasis is the most prevalent but neglected tropical disease in the world, affecting approximately 450 million people. The initial phase of Ascaris infection is marked by larval migration from the host's organs, causing mechanical injuries followed by an intense local inflammatory response, which is characterized mainly by neutrophil and eosinophil infiltration, especially in the lungs. During the pulmonary phase, the lesions induced by larval migration and excessive immune responses contribute to tissue remodeling marked by fibrosis and lung dysfunction. In this study, we investigated the relationship between SIgA levels and eosinophils. We found that TLR2 and TLR4 signaling induces eosinophils and promotes SIgA production during Ascaris suum infection. Therefore, control of parasite burden during the pulmonary phase of ascariasis involves eosinophil influx and subsequent promotion of SIgA levels. In addition, we also demonstrate that eosinophils also participate in the process of tissue remodeling after lung injury caused by larval migration, contributing to pulmonary fibrosis and dysfunction in re-infected mice. In conclusion, we postulate that eosinophils play a central role in mediating host innate and humoral immune responses by controlling parasite burden, tissue inflammation, and remodeling during Ascaris suum infection. Furthermore, we suggest that the use of probiotics can induce eosinophilia and SIgA production and contribute to controlling parasite burden and morbidity of helminthic diseases with pulmonary cycles.


Assuntos
Ascaríase/imunologia , Ascaris suum/imunologia , Eosinófilos/fisiologia , Imunoglobulina A Secretora/metabolismo , Pneumonia/prevenção & controle , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Ascaríase/metabolismo , Ascaríase/parasitologia , Feminino , Imunoglobulina A Secretora/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pneumonia/imunologia , Pneumonia/parasitologia , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética
3.
Biomed Chromatogr ; 37(10): e5699, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37427763

RESUMO

Homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) are the urinary metabolites of dopamine (DA) and serotonin (5-HA), respectively. We aimed to develop an extraction method for the determination of HVA and 5-HIAA, using strong anionic exchange cartridges combined with HPLC with electrochemical detection, and apply it to measure the levels of HVA and 5-HIAA in children living near a ferro-manganese alloy plant in Simões Filho, Brazil. The validated method showed good selectivity, sensitivity, precision, and accuracy. The limits of detection (LOD) were 4 and 8 µmol/L for 5-HIAA and HVA, respectively, in urine. Recoveries ranged from 85.8 to 94%. The coefficients of determination (R2 ) of the calibration curves were greater than 0.99. Spot urine samples of 30 exposed children and 20 nonexposed ones were processed accordingly. The metabolite levels in exposed and reference children were within the physiological ranges. The medians (range) for 5-HIAA and HVA of the exposed ones were 36.4 µmol/L (18.4-58.0) and 32.9 µmol/L (

Assuntos
Dopamina , Manganês , Humanos , Criança , Ácido Homovanílico/urina , Ácido Hidroxi-Indolacético , Cromatografia Líquida de Alta Pressão/métodos , Dopamina/metabolismo
4.
PLoS Biol ; 17(4): e3000080, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31002659

RESUMO

Hemodynamic recordings from visual cortex contain powerful endogenous task-related responses that may reflect task-related arousal, or "task engagement" distinct from attention. We tested this hypothesis with hemodynamic measurements (intrinsic-signal optical imaging) from monkey primary visual cortex (V1) while the animals' engagement in a periodic fixation task over several hours was varied through reward size and as animals took breaks. With higher rewards, animals appeared more task-engaged; task-related responses were more temporally precise at the task period (approximately 10-20 seconds) and modestly stronger. The 2-5 minute blocks of high-reward trials led to ramp-like decreases in mean local blood volume; these reversed with ramp-like increases during low reward. The blood volume increased even more sharply when the animal shut his eyes and disengaged completely from the task (5-10 minutes). We propose a mechanism that controls vascular tone, likely along with local neural responses in a manner that reflects task engagement over the full range of timescales tested.


Assuntos
Atenção/fisiologia , Hemodinâmica/fisiologia , Córtex Visual/fisiologia , Animais , Comportamento Animal/fisiologia , Mapeamento Encefálico/métodos , Macaca mulatta , Masculino , Neurônios/fisiologia , Tempo de Reação/fisiologia , Recompensa
5.
Microb Pathog ; 151: 104745, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33485994

RESUMO

Treatment for visceral leishmaniasis (VL) is hampered mainly by the toxicity and/or high cost of antileishmanial drugs. What is more, variability on sensitivity and/or specificity of diagnostic tests hinders effective disease management. In this context, prophylactic vaccination should be considered as a strategy to prevent disease. In the present study, immunogenicity of the Leishmania eukaryotic Elongation Factor-1 beta (EF1b) protein, classified as a Leishmania virulence factor, was evaluated in vitro and in vivo and tested, for the first time, as a vaccine candidate against Leishmania infantum infection. The antigen was administered as DNA vaccine or as recombinant protein (rEF1b) delivered in saponin. BALB/c mice immunization with a DNA plasmid and recombinant protein plus saponin induced development of specific Th1-type immunity, characterized by high levels of IFN-γ, IL-12, GM-CSF, both T cell subtypes and antileishmanial IgG2a isotype antibodies, before and after infection. This immunological response to the vaccines was corroborated further by parasitological analysis of the vaccinated and then challenged mice, which showed significant reductions in the parasite load in their liver, spleen, bone marrow and draining lymph nodes, when compared to the controls. Vaccination using rEF1b/saponin induced a more robust Th1 response and parasitological protection when compared to the DNA vaccine. Furthermore, in vitro analysis of lymphoproliferation, IFN-γ and IL-10 levels in human PBMC cultures showed as well development of a specific Th1-type response. In conclusion, data suggest that EF1b could be a promising vaccine candidate to protect against L. infantum infection.


Assuntos
Leishmania infantum , Vacinas contra Leishmaniose , Animais , Antígenos de Protozoários/genética , Leucócitos Mononucleares , Camundongos , Camundongos Endogâmicos BALB C , Fatores de Alongamento de Peptídeos
6.
Parasite Immunol ; 43(12): e12880, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34558674

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) is a serious public health problem. The factors that can determine whether VL develops and progresses to severe form have not been fully identified, but a specific cellular immune response appears to play a key role. Therefore, understanding immunopathogenesis can be useful in preventing a serious clinical outcome. MATERIALS AND METHODS: Bone marrow samples were collected from patients with severe VL (SVL) or non-severe VL (NSVL). Cytokine levels and parasitic load were analysed by RT-qPCR. There is a statistically significant difference in the leukocyte parameter in patients with SVL and NSVL compared with the control patients (p = .006 and p = .014, respectively). RESULTS: Urea, alanine transaminase and albumin parameters had a significant difference p = .036, p = .039 and p = .017, respectively, between SVL and NSVL. Although high levels of IFN-γ, IL-10, IL-6 and TNF-α were present in all groups of individuals with VL, they were not statistically associated with severity. In patients with active VL, IFN-γ and IL-10 were associated, respectively, with a reduction and increase in the parasite load, strong and significant positive association between IFN-γ and IL-10 (rho = .627 and p = .003). CONCLUSION: This study demonstrates that VL stimulates an non-dichotomized inflammatory response between Th1/Th2 and that bone marrow is an important tissue for immune regulation.


Assuntos
Leishmaniose Visceral , Citocinas/metabolismo , Humanos , Interferon gama , Carga Parasitária , Fator de Necrose Tumoral alfa/metabolismo
7.
Scand J Med Sci Sports ; 31(3): 610-622, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33176018

RESUMO

Cryotherapy is a therapeutic modality widely used for the treatment of muscle injuries to control pain and inflammatory processes. This study aimed to investigate the effects of cryotherapy on the inflammatory and oxidative stress parameters and mechanical properties of, and pain in, the skeletal muscles of rats with lacerative muscle injury. The rats were anesthetized with 4% isoflurane and subjected to gastrocnemius muscle laceration injury. After injury, all animals in the intervention groups received cryotherapy treatment for 20 minutes using plastic bags containing crushed ice. The protocol comprised three daily applications at 3-hour intervals on the day of injury, with reapplication 24 hours later. Seventy-two male Wistar rats were divided into three groups: sham, muscle injury (MI), and MI + cryotherapy (MI + cryo). Muscle mechanical properties were analyzed by mechanical tensile testing on day 7 after injury. The MI + cryo group showed reduced TNF-α, IFN-γ, and IL1ß levels; elevated IL4, IL6, and IL10 levels; reduced oxidant production and carbonyl levels; and elevated sulfhydryl contents. Animals that underwent tissue cooling showed superoxide dismutase activity and glutathione levels close to those of the animals in the sham group. The MI and MI + cryo groups showed reduced values of the evaluated mechanical properties and lower mechanical thresholds compared to those of the animals from the sham group. Our results demonstrated that the proposed cryotherapy protocol reduced the inflammatory process and controlled oxidative stress but did not reverse the changes in the mechanical properties of muscle tissues or provide analgesic effects within the time frame analyzed.


Assuntos
Crioterapia , Lacerações/fisiopatologia , Lacerações/terapia , Músculo Esquelético/lesões , Músculo Esquelético/fisiologia , Cicatrização/fisiologia , Animais , Citocinas/sangue , Fluoresceínas/metabolismo , Glutationa/metabolismo , Inflamação/fisiopatologia , Masculino , Músculo Esquelético/metabolismo , Nitritos/metabolismo , Oxirredução , Estresse Oxidativo , Ratos Wistar , Superóxido Dismutase/metabolismo , Resistência à Tração
8.
Int Arch Occup Environ Health ; 94(5): 1061-1071, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33606099

RESUMO

BACKGROUND AND PURPOSE: Lead (Pb) is used as a flux in the glazing process of pottery utensils in several regions of the world. It can affect the nervous and hematopoietic systems; in addition, it is classified as a probable human carcinogen. This work aims to evaluate Pb exposure of potters and describe the main determinants of elevated blood Pb (PbB) levels in this group of workers. METHODS: This is a cross-sectional study with potters of Maragogipinho Village, Bahia, Brazil, of both sexes, aged 16-72 years (n = 85). Non-exposed workers of the same age range residing in the urban area of Aratuípe town were also recruited (n = 50). We evaluated Pb dust deposition rates (PbDrt) in pottery workshops and PbB levels. All Pb measurements were performed by Graphite Furnace Atomic Absorption Spectrometry. RESULTS: The median of PbB (min-max) and geometric mean (SD) PbDrt for the exposed group were 7.9 (0.9-49.8) µg/dL and 1463 (± 290,000) µg/m2/30 days, respectively. For the control group, levels were 1.5 (0.1-19.8) µg/dL and 82 (46) µg/m2 30 days, respectively. CONCLUSION: The data found showed an excessive exposure among artisans, exceeding occupationally safe levels and those reported in the literature. It is important to implement occupational hygiene measures and improvements of the working conditions of these labors, especially the replacement of lead oxide in the pottery-glazing process.


Assuntos
Cerâmica , Poeira/análise , Chumbo/análise , Exposição Ocupacional/análise , Adolescente , Adulto , Idoso , Brasil , Estudos Transversais , Monitoramento Ambiental , Feminino , Humanos , Chumbo/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
9.
Biomed Chromatogr ; 35(2): e4983, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32909293

RESUMO

Lead (Pb) exposure compromises heme synthesis by inhibiting ferrochelatase, forming zinc-protoporphyrin (ZnPP). This study aims to validate a method for the determination of ZnPP by HPLC with fluorescence detection and apply this method to evaluate the extent of Pb exposure of artisanal pottery workers. Extraction procedures were tested using both nonacid and acid liquid-liquid extraction. The former presented a better chromatogram and recovery results. The validated method yielded a good resolution of ZnPP and its free form peaks with acceptable precision and accuracy. Total run time was 15 min and ZnPP peak retention time was 5.6 min. We applied this method to evaluate 39 potters (90% male), mean age 40 years (9-80). The medians (ranges) of blood lead, ZnPP and hemoglobin were 16.0 µg/dl (2.2-71.5), 12.6 µg/dl (4.6-279.8) and 15.1 g/dl (11.0-17.8), respectively. Significant differences were observed for blood lead according to gender, age range (>40 years), direct handling of lead oxide and years of occupation. Significantly higher levels of ZnPP were observed in male potters involved with lead glazing activity. The validated method was shown to be simple with one-step nonacid extraction, good sensitivity, reproducibility and accuracy. Our data shows that these laborers are dangerously exposed to Pb, reflecting the effect on the heme synthesis.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Chumbo/sangue , Exposição Ocupacional/análise , Protoporfirinas/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Criança , Feminino , Hemoglobinas/análise , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência , Adulto Jovem
10.
Microb Pathog ; 147: 104373, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32645421

RESUMO

Mycobacterium leprae infection depends on the competence of the host immune defense to induce effective protection against this intracellular pathogen. The present study investigated the serum levels of vitamin D and the antimicrobial peptide cathelicidin, to determine the statistical correlation between them in leprosy patients before and post-six months of multidrug therapy (MDT), household contacts, and healthy individuals. Previous studies associated these molecules with high risks to develop mycobacterial diseases, such as tuberculosis and leprosy. A total of 34 leprosy patients [paucibacillary (n = 14), multibacillary (n = 20)], and 25 household contacts were recruited. Eighteen healthy adults were selected as a control group. Serum concentrations of vitamin D (25(OH)VD3) and cathelicidin were measured using high-performance liquid chromatography (HPLC), and an enzyme-linked immunosorbent assay (ELISA) kit, respectively. There were no significant differences in serum levels of 25(OH)VD3 between all groups, and the overall prevalence rate of vitamin D deficiency was 67.1%. Cathelicidin levels were significantly lower in both untreated and treated patients when compared to controls and household contacts (p < 0.05). Strong correlations between hypovitaminosis D and reduced cathelicidin in untreated (r = 0.86) and post-six months of MDT (r = 0.79) leprosy patients were observed. These results suggest that vitamin D status and cathelicidin levels are strongly correlated during multidrug therapy for leprosy and nutritional supplementation from the beginning of treatment could strengthen the immune response against leprosy.


Assuntos
Hanseníase , Deficiência de Vitamina D , Adulto , Antígenos de Bactérias , Peptídeos Catiônicos Antimicrobianos , Quimioterapia Combinada , Ensaio de Imunoadsorção Enzimática , Humanos , Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Mycobacterium leprae , Deficiência de Vitamina D/tratamento farmacológico , Catelicidinas
11.
Microb Pathog ; 137: 103783, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31600536

RESUMO

The laboratorial diagnosis of leishmaniasis is based on parasitological methods, which are invasive, present high cost, require laboratorial infrastructure and/or trained professionals; as well as by immunological methods, which usually present variable sensitivity and/or specificity, such as when they are applied to identify asymptomatic cases and/or mammalian hosts presenting low levels of antileishmanial antibodies. As consequence, new studies aiming to identify more refined antigens to diagnose visceral (VL) and tegumentary (TL) leishmaniasis are urgently necessary. In the present work, the Leishmania eukaryotic elongation factor-1 beta (EF1b) protein, which was identified in L. infantum protein extracts by antibodies in VL patients' sera, was cloned and its recombinant version (rEF1b) was expressed, purified and tested as a diagnostic marker for VL and TL. The post-therapeutic serological follow-up was also evaluated in treated and untreated VL and TL patients, when anti-rEF1b antibody levels were measured before and after treatment. Results showed that rEF1b was highly sensitive and specific to diagnose symptomatic and asymptomatic canine VL, as well as human TL and VL. In addition, low cross-reactivity was observed when sera from healthy subjects or leishmaniasis-related diseases patients were tested. The serological follow-up showed also that rEF1b-specific antibodies declined significantly after treatment, suggesting that this protein could be also evaluated as a prognostic marker for human leishmaniasis.


Assuntos
Doenças do Cão/parasitologia , Fator de Iniciação 1 em Eucariotos/imunologia , Leishmania infantum/imunologia , Leishmaniose Visceral/parasitologia , Leishmaniose Visceral/veterinária , Proteínas de Protozoários/imunologia , Adulto , Animais , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Reações Cruzadas , Doenças do Cão/diagnóstico , Doenças do Cão/imunologia , Cães , Ensaio de Imunoadsorção Enzimática , Fator de Iniciação 1 em Eucariotos/genética , Feminino , Humanos , Leishmania infantum/genética , Leishmania infantum/isolamento & purificação , Leishmaniose/diagnóstico , Leishmaniose/imunologia , Leishmaniose/parasitologia , Leishmaniose/veterinária , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/imunologia , Masculino , Pessoa de Meia-Idade , Proteínas de Protozoários/genética , Testes Sorológicos
13.
J Clin Ultrasound ; 47(4): 232-234, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30511740

RESUMO

Isolated fetal ascites and cri-du-chat syndrome (CdCS; OMIM #123450) are two very rare conditions that, to our best knowledge, have never been reported together. Here, we describe a case of isolated fetal ascites detected in the first trimester ultrasound, with no other remarkable signs. After an extensive work-up (fetal ultrasound, serologies, Coombs test, and NIPT), an amniocentesis was performed and revealed an abnormal karyotype of 46,XX,del(5)(p15.2), characteristic of CdCS. We hypothesize that isolated fetal ascites has to be considered an antenatal ultrasonographic marker for CdCS, a finding that should be confirmed in further cases.


Assuntos
Ascite/diagnóstico por imagem , Ascite/embriologia , Síndrome de Cri-du-Chat/diagnóstico por imagem , Síndrome de Cri-du-Chat/embriologia , Ultrassonografia Pré-Natal/métodos , Aborto Eugênico , Adulto , Amniocentese , Ascite/complicações , Síndrome de Cri-du-Chat/complicações , Feminino , Humanos , Gravidez
14.
Gastroenterol Hepatol ; 42(5): 296-303, 2019 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30772084

RESUMO

INTRODUCTION: Acute-on-chronic liver failure (ACLF) is a dynamic syndrome that should be assessed repeatedly. An algorithm for risk stratification in decompensated cirrhosis was recently proposed by the EASL-CLIF (European Association for the Study of the Liver-Chronic Liver Failure) Consortium. AIM: To validate the EASL-CLIF Consortium scores in patients with and without ACLF. MATERIALS AND METHODS: Retrospective single-center cohort study including patients admitted for acute decompensation of cirrhosis between January 2014 and December 2015, and followed-up until December 2016. We separated patients with and without ACLF and compared the various EASL-CLIF Consortium scores to Child-Pugh and MELD for predicting 28-day (M28), 90-day and 12-month mortality. These scores were recalculated at different time points over 28 days. RESULTS: 106 patients were included (age 60.3±10.7 years; 87.7% male), 35.8% of whom met ACLF criteria on admission (50%) or during hospitalization. A CLIF-C AD Score ≥60 on admission was associated with a higher risk of developing ACLF. The onset of ACLF during hospitalization portended a poor prognosis. The prognostic performance of the CLIF-C ACLF Score (AUROC for M28: 0.856±0.071) was globally comparable to that of Child-Pugh and MELD. Overall, ACLF resolved in 54.1% patients, resulting in increased survival. Almost 40% of the patients reached their final ACLF grade after ≥8 days, with 13.9% of ACLF patients experiencing resolution by then. DISCUSSION: We confirmed the accuracy and clinical value of the several proposed scores in our population. Prognosis was better defined by the early clinical course than by the initial evaluation, emphasizing the importance of repeated assessments.


Assuntos
Insuficiência Hepática Crônica Agudizada/diagnóstico , Insuficiência Hepática Crônica Agudizada/etiologia , Algoritmos , Cirrose Hepática/complicações , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Portugal , Estudos Retrospectivos , Medição de Risco
15.
BMC Genomics ; 19(1): 816, 2018 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-30424726

RESUMO

BACKGROUND: Trypanosoma cruzi, the etiologic agent of Chagas disease, is currently divided into six discrete typing units (DTUs), named TcI-TcVI. TcII is among the major DTUs enrolled in human infections in South America southern cone, where it is associated with severe cardiac and digestive symptoms. Despite the importance of TcII in Chagas disease epidemiology and pathology, so far, no genome-wide comparisons of the mitochondrial and nuclear genomes of TcII field isolates have been performed to track the variability and evolution of this DTU in endemic regions. RESULTS: In the present work, we have sequenced and compared the whole nuclear and mitochondrial genomes of seven TcII strains isolated from chagasic patients from the central and northeastern regions of Minas Gerais, Brazil, revealing an extensive genetic variability within this DTU. A comparison of the phylogeny based on the nuclear or mitochondrial genomes revealed that the majority of branches were shared by both sequences. The subtle divergences in the branches are probably consequence of mitochondrial introgression events between TcII strains. Two T. cruzi strains isolated from patients living in the central region of Minas Gerais, S15 and S162a, were clustered in the nuclear and mitochondrial phylogeny analysis. These two strains were isolated from the other five by the Espinhaço Mountains, a geographic barrier that could have restricted the traffic of insect vectors during T. cruzi evolution in the Minas Gerais state. Finally, the presence of aneuploidies was evaluated, revealing that all seven TcII strains have a different pattern of chromosomal duplication/loss. CONCLUSIONS: Analysis of genomic variability and aneuploidies suggests that there is significant genomic variability within Minas Gerais TcII strains, which could be exploited by the parasite to allow rapid selection of favorable phenotypes. Also, the aneuploidy patterns vary among T. cruzi strains and does not correlate with the nuclear phylogeny, suggesting that chromosomal duplication/loss are recent and frequent events in the parasite evolution.


Assuntos
Aneuploidia , Doença de Chagas/parasitologia , Variação Genética , Genoma de Protozoário , Proteínas de Protozoários/genética , Trypanosoma cruzi/genética , Sequenciamento Completo do Genoma/métodos , Animais , Doença de Chagas/transmissão , DNA de Protozoário/genética , Genótipo , Humanos , Insetos Vetores/parasitologia , Tipagem Molecular , Filogenia , Trypanosoma cruzi/classificação , Trypanosoma cruzi/isolamento & purificação
16.
Molecules ; 23(4)2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29596367

RESUMO

Carbene transfer reactions are very important transformations in organic synthesis, allowing the generation of structurally challenging products by catalysed cyclopropanation, cyclopropenation, carbene C-H, N-H, O-H, S-H, and Si-H insertion, and olefination of carbonyl compounds. In particular, chiral and achiral metalloporphyrins have been successfully explored as biomimetic catalysts for these carbene transfer reactions under both homogeneous and heterogeneous conditions. In this work the use of synthetic metalloporphyrins (MPorph, M = Fe, Ru, Os, Co, Rh, Ir, Sn) as homogeneous or heterogeneous catalysts for carbene transfer reactions in the last years is reviewed, almost exclusively focused on the literature since the year 2010, except when reference to older publications was deemed to be crucial.


Assuntos
Metaloporfirinas/química , Metano/análogos & derivados , Metano/química
17.
BMC Bioinformatics ; 18(1): 104, 2017 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-28187714

RESUMO

BACKGROUND: Molecular genetic markers are one of the most informative and widely used genome features in clinical and environmental diagnostic studies. A polymerase chain reaction (PCR)-based molecular marker is very attractive because it is suitable to high throughput automation and confers high specificity. However, the design of taxon-specific primers may be difficult and time consuming due to the need to identify appropriate genomic regions for annealing primers and to evaluate primer specificity. RESULTS: Here, we report the development of a Tool for Identification of Primers for Multiple Taxa (TipMT), which is a web application to search and design primers for genotyping based on genomic data. The tool identifies and targets single sequence repeats (SSR) or orthologous/taxa-specific genes for genotyping using Multiplex PCR. This pipeline was applied to the genomes of four species of Leishmania (L. amazonensis, L. braziliensis, L. infantum and L. major) and validated by PCR using artificial genomic DNA mixtures of the Leishmania species as templates. This experimental validation demonstrates the reliability of TipMT because amplification profiles showed discrimination of genomic DNA samples from Leishmania species. CONCLUSIONS: The TipMT web tool allows for large-scale identification and design of taxon-specific primers and is freely available to the scientific community at http://200.131.37.155/tipMT/ .


Assuntos
Primers do DNA/metabolismo , Marcadores Genéticos/genética , Reação em Cadeia da Polimerase , Interface Usuário-Computador , Primers do DNA/química , Genoma de Protozoário , Internet , Leishmania/genética
18.
PLoS Pathog ; 11(12): e1005296, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26641088

RESUMO

Leishmaniasis, a human parasitic disease with manifestations ranging from cutaneous ulcerations to fatal visceral infection, is caused by several Leishmania species. These protozoan parasites replicate as extracellular, flagellated promastigotes in the gut of a sandfly vector and as amastigotes inside the parasitophorous vacuole of vertebrate host macrophages. Amastins are surface glycoproteins encoded by large gene families present in the genomes of several trypanosomatids and highly expressed in the intracellular amastigote stages of Trypanosoma cruzi and Leishmania spp. Here, we showed that the genome of L. braziliensis contains 52 amastin genes belonging to all four previously described amastin subfamilies and that the expression of members of all subfamilies is upregulated in L. braziliensis amastigotes. Although primary sequence alignments showed no homology to any known protein sequence, homology searches based on secondary structure predictions indicate that amastins are related to claudins, a group of proteins that are components of eukaryotic tight junction complexes. By knocking-down the expression of δ-amastins in L. braziliensis, their essential role during infection became evident. δ-amastin knockdown parasites showed impaired growth after in vitro infection of mouse macrophages and completely failed to produce infection when inoculated in BALB/c mice, an attenuated phenotype that was reverted by the re-expression of an RNAi-resistant amastin gene. Further highlighting their essential role in host-parasite interactions, electron microscopy analyses of macrophages infected with amastin knockdown parasites showed significant alterations in the tight contact that is normally observed between the surface of wild type amastigotes and the membrane of the parasitophorous vacuole.


Assuntos
Interações Hospedeiro-Parasita/fisiologia , Leishmania braziliensis/patogenicidade , Leishmaniose Cutânea/genética , Macrófagos/parasitologia , Proteínas de Protozoários/genética , Sequência de Aminoácidos , Animais , Northern Blotting , Western Blotting , Modelos Animais de Doenças , Leishmania braziliensis/genética , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Transfecção , Virulência
19.
Malar J ; 16(1): 42, 2017 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-28118834

RESUMO

BACKGROUND: The clinical outcome of malaria depends on the delicate balance between pro-inflammatory and immunomodulatory cytokine responses triggered during infection. Despite the numerous reports on characterization of plasma levels of cytokines/chemokines, there is no consensus on the profile of these mediators during blood stage malaria. The identification of acute phase biomarkers might contribute to a better understanding of the disease, allowing the use of more effective therapeutic approaches to prevent the progression towards severe disease. In the present study, the plasma levels of cytokines and chemokines and their association with parasitaemia and number of previous malaria episodes were evaluated in Plasmodium vivax-infected patients during acute and convalescence phase, as well as in healthy donors. METHODS: Samples of plasma were obtained from peripheral blood samples from four different groups: P. vivax-infected, P. vivax-treated, endemic control and malaria-naïve control. The cytokine (IL-6, IL-10, IL-17, IL-27, TGF-ß, IFN-γ and TNF) and chemokine (MCP-1/CCL2, IP-10/CXCL10 and RANTES/CCL5) plasma levels were measured by CBA or ELISA. The network analysis was performed using Spearman correlation coefficient. RESULTS: Plasmodium vivax infection induced a pro-inflammatory response driven by IL-6 and IL-17 associated with an immunomodulatory profile mediated by IL-10 and TGF-ß. In addition, a reduction was observed of IFN-γ plasma levels in P. vivax group. A lower level of IL-27 was observed in endemic control group in comparison to malaria-naïve control group. No significant results were found for IL-12p40 and TNF. It was also observed that P. vivax infection promoted higher levels of MCP-1/CCL2 and IP-10/CXCL10 and lower levels of RANTES/CCL5. The plasma level of IL-10 was elevated in patients with high parasitaemia and with more than five previous malaria episodes. Furthermore, association profile between cytokine and chemokine levels were observed by correlation network analysis indicating signature patterns associated with different parasitaemia levels. CONCLUSIONS: The P. vivax infection triggers a balanced immune response mediated by IL-6 and MCP-1/CCL2, which is modulated by IL-10. In addition, the results indicated that IL-10 plasma levels are influenced by parasitaemia and number of previous malaria episodes.


Assuntos
Citocinas/sangue , Malária Vivax/imunologia , Malária Vivax/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imunoensaio , Masculino , Pessoa de Meia-Idade , Plasma/química , Adulto Jovem
20.
Molecules ; 22(2)2017 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-28212345

RESUMO

New sulfonyl-lapachones were efficiently obtained through the catalytic oxidation of arylthio- and cyclohexylthio-lapachone derivatives with hydrogen peroxide in the presence of a Mn(III) porphyrin complex. The antibacterial activities of the non-oxidized and oxidized lapachone derivatives against the Gram-negative bacteria Escherichia coli and the Gram-positive bacteria Staphylococcus aureus were evaluated after their incorporation into polyvinylpyrrolidone (PVP) micelles. The obtained results show that the PVP-formulations of the lapachones 4b-g and of the sulfonyl-lapachones 7e and 7g reduced the growth of S. aureus.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/síntese química , Catálise , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Naftoquinonas/química , Naftoquinonas/farmacologia , Oxirredução , Ácidos Sulfínicos/química
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