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2.
Semin Cell Dev Biol ; 112: 27-36, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32513499

RESUMO

Bone marrow (BM) is a preferential metastatic site for solid cancers, contributing to higher morbidity and mortality among millions of oncologic patients worldwide. There are no current efficient therapies to minimize this health burden. Microfluidic based in vitro models emerge as powerful alternatives to animal testing, as well as promising tools for the development of personalized medicine solutions. The complexity associated with the BM metastatic niche originated a wide variety of microfluidic platforms designed to mimic this microenvironment. This review gathers the essential parameters to design an accurate in vitro microfluidic device, based on a comparative analysis of existing models created to address the different steps of the metastatic cascade.


Assuntos
Microfluídica , Metástase Neoplásica/genética , Neoplasias/genética , Nicho de Células-Tronco/genética , Humanos , Metástase Neoplásica/patologia , Neoplasias/patologia , Medicina de Precisão , Microambiente Tumoral/genética
3.
Cytokine ; 129: 155031, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32062145

RESUMO

The control measures against visceral leishmaniasis (VL) include a precise diagnosis of disease, the treatment of human cases, and reservoir and vector controls. However, these are insufficient to avoid the spread of the disease in specific countries worldwide. As a consequence, prophylactic vaccination could be interesting, although no effective candidate against human disease is available. In the present study, the Leishmania infantum amastin protein was evaluated regarding its immunogenicity and protective efficacy against experimental VL. BALB/c mice immunized with subcutaneous injections of the recombinant protein with or without liposome/saponin (Lip/Sap) as an adjuvant. After immunization, half of the animals per group were euthanized and immunological evaluations were performed, while the others were challenged with L. infantum promastigotes. Forty-five days after infection, the animals were euthanized and parasitological and immunological evaluations were performed. Results showed the development of a Th1-type immune response in rAmastin-Lip and rAmastin-Sap/vaccinated mice, before and after infection, which was based on the production of protein and parasite-specific IFN-γ, IL-12, GM-CSF, and nitrite, as well as the IgG2a isotype antibody. CD4+ T cells were mainly responsible for IFN-γ production in vaccinated mice, which also presented significant reductions in parasitism in their liver, spleen, draining lymph nodes, and bone marrow. In addition, PBMC cultures of treated VL patients and healthy subjects stimulated with rAmastin showed lymphoproliferation and higher IFN-γ production. In conclusion, the present study shows the first case of an L. infantum amastin protein associated with distinct delivery systems inducing protection against L. infantum infection and demonstrates an immunogenic effect of this protein in human cells.


Assuntos
Leishmania infantum/imunologia , Leishmaniose Visceral/imunologia , Proteínas de Protozoários/imunologia , Adjuvantes Imunológicos/farmacologia , Sequência de Aminoácidos , Animais , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/parasitologia , Células Cultivadas , Feminino , Humanos , Imunidade/imunologia , Interferon gama/imunologia , Leishmaniose Visceral/parasitologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/parasitologia , Linfonodos/imunologia , Linfonodos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/imunologia , Células Th1/imunologia , Células Th1/parasitologia
4.
Int J Legal Med ; 134(5): 1765-1774, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32592073

RESUMO

Timing of cranial trauma is challenging in forensic cases and literature on the subject is scarce. This study analysed the macroscopic fracture patterns of perimortem cranial fractures and compared them to experimentally reproduced cranial fractures on dry human craniums. The results showed nine traits associated with fresh cranial fractures: undulated margin, flake defects, peels with peel defects, fissures, crushed margins, bridge, bone scales and beveling. All the traits appear on the outer table or on the inner table of the cranium. Although not all characteristics must be present at the same time in all cranial fractures, they do define a new perimortem fracture pattern. Statistical analyses showed that six of these traits (undulated margins, flake defects, crushed margins, bone scales, fissures and peels) are distinctly related with perimortem (fresh) bone conditions. Considering the most discriminant perimortem traits, a decision-making algorithm is developed as a probabilistic approach to distinguish peri- from postmortem cranial fractures with an accuracy of 87%. This algorithm allows the forensic practitioner to incorporate more confidence during cranial trauma evaluation.


Assuntos
Medicina Legal/métodos , Fraturas Cranianas/patologia , Crânio/lesões , Adulto , Idoso , Algoritmos , Árvores de Decisões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mudanças Depois da Morte
5.
Epilepsy Behav ; 112: 107469, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33181902

RESUMO

The most common form of genetic generalized epilepsy (GGE) is juvenile myoclonic epilepsy (JME), which accounts for 5 to 10% of all epilepsy cases. The gene EFHC1 has been implicated as a putative cause of JME. However, it remains debatable whether testing for EFHC1 mutations should be included in the diagnostic epilepsy gene panels. To investigate the clinical utility of EFHC1 testing, we studied 125 individuals: 100 with JME and 25 with other GGEs. We amplified and sequenced all EFHC1 coding exons. Then, we predicted the pathogenicity or benign impact of the variants using the analyses proposed by the American College of Medical Genetics and Genomics (ACMG)/Association for Molecular Pathology (AMP). Mutation screening revealed 11 missense variants in 44 probands with JME (44%) and one of the seven individuals with generalized tonic-clonic seizures on awakening (14%). Six of the 11 variants (54%) were classified as 'benign,' and the remaining variants were considered variants of uncertain significance (VUS). There is currently a limitation to test for genes that predispose an individual to complex, nonmonogenic phenotypes. Thus, we show suggestive evidence that EFHC1 testing lacks a scientific foundation based on the disputed nature of the gene-disease relationship and should be currently limited to research purposes.


Assuntos
Epilepsia Generalizada , Epilepsia Mioclônica Juvenil , Proteínas de Ligação ao Cálcio/genética , Epilepsia Generalizada/genética , Humanos , Epilepsia Mioclônica Juvenil/genética , Linhagem , Fenótipo
6.
Orthod Craniofac Res ; 23(2): 223-228, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31889381

RESUMO

OBJECTIVES: The purpose of this study was to assess the accuracy of linear measurements performed in multiplanar reconstructions (MPR) and sagittal reconstructions (SR) of the left hemiface obtained from cone-beam computed tomography (CBCT) with 3D® Dolphin Imaging software by comparing them with the same measurements made on lateral cephalograms and on dry skulls. SETTING AND SAMPLE POPULATION: Lateral cephalograms and CBCT (with voxels of 0.25, 0.3 and 0.4 mm) were taken of 10 dry skulls. MATERIALS AND METHODS: Linear distances were measured using the software's electronic rulers. Measurements performed on dry skulls using a digital caliper were considered the gold standard. The measurements were performed twice by two evaluators. RESULTS: No significant difference was found in the measurements performed with the different imaging modalities and on the dry skulls. The highest mean error was observed in the lateral cephalograms, followed by MPR and SR. CONCLUSIONS: Cephalometric measurements performed on multiplanar and sagittal reconstructions from CBCT, with different spatial resolutions, are accurate when compared with the measurements obtained in lateral cephalograms.


Assuntos
Tomografia Computadorizada de Feixe Cônico Espiral , Cefalometria , Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional , Reprodutibilidade dos Testes
7.
Parasitol Res ; 119(8): 2609-2622, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32535734

RESUMO

The treatment against visceral leishmaniasis (VL) presents problems, mainly related to the toxicity and/or high cost of the drugs. In this context, a prophylactic vaccination is urgently required. In the present study, a Leishmania protein called LiHyE, which was suggested recently as an antigenic marker for canine and human VL, was evaluated regarding its immunogenicity and protective efficacy in BALB/c mice against Leishmania infantum infection. In addition, the protein was used to stimulate peripheral blood mononuclear cells (PBMCs) from VL patients before and after treatment, as well as from healthy subjects. Vaccination results showed that the recombinant (rLiHyE) protein associated with liposome or saponin induced effective protection in the mice, since significant reductions in the parasite load in spleen, liver, draining lymph nodes, and bone marrow were found. The parasitological protection was associated with Th1-type cell response, since high IFN-γ, IL-12, and GM-CSF levels, in addition to low IL-4 and IL-10 production, were found. Liposome induced a better parasitological and immunological protection than did saponin. Experiments using PBMCs showed rLiHyE-stimulated lymphoproliferation in treated patients' and healthy subjects' cells, as well as high IFN-γ levels in the cell supernatant. In conclusion, rLiHyE could be considered for future studies as a vaccine candidate against VL.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Antígenos de Protozoários/administração & dosagem , Leishmania infantum/imunologia , Leishmaniose Visceral/prevenção & controle , Animais , Antígenos de Protozoários/imunologia , Feminino , Humanos , Imunogenicidade da Vacina , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Leucócitos Mononucleares/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Carga Parasitária , Células Th1/imunologia , Vacinação
8.
Mol Phylogenet Evol ; 137: 44-63, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30999036

RESUMO

With 145 species, Turnera is the largest genus of Turneraceae (Malpighiales). Despite several morphotaxonomic and cytogenetic studies, our knowledge about the phylogenetic relationships in Turnera remains mainly based on morphological data. Here, we reconstruct the most comprehensive phylogeny of Turnera with molecular data to understand the morphological evolution within this group and to assess its circumscription and infrageneric classification. We analyzed two nuclear and six plastid markers and 112 taxa, including species and infraspecific taxa, 97 from Turnera, covering the 11 series of the genus. Bayesian inference, maximum parsimony and maximum likelihood analyses show that Turnera, as traditionally circumscribed, is not monophyletic. The genus is divided into two well-supported independent clades; one of them is sister to the genus Piriqueta and is here segregated as the new genus Oxossia. According to our reconstructions, Turnera probably evolved from an ancestor without extrafloral nectaries and with solitary, homostylous flowers with yellow petals. The emergences of extrafloral nectaries and distyly, both common in extant taxa, played an important role in the diversification of the genus. An updated infrageneric classification reflecting the relationships within Turnera is now possible based on morphological synapomorphies and is here designed for further studies.


Assuntos
Classificação , Filogenia , Turnera/anatomia & histologia , Turnera/genética , Teorema de Bayes , Biodiversidade , Sequência Consenso , Inflorescência/genética , Tricomas/genética , Turnera/classificação
9.
Parasitology ; 146(11): 1467-1476, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31142384

RESUMO

There is no suitable vaccine against human visceral leishmaniasis (VL) and available drugs are toxic and/or present high cost. In this context, diagnostic tools should be improved for clinical management and epidemiological evaluation of disease. However, the variable sensitivity and/or specificity of the used antigens are limitations, showing the necessity to identify new molecules to be tested in a more sensitive and specific serology. In the present study, an immunoproteomics approach was performed in Leishmania infantum promastigotes and amastigotes employing sera samples from VL patients. Aiming to avoid undesired cross-reactivity in the serological assays, sera from Chagas disease patients and healthy subjects living in the endemic region of disease were also used in immunoblottings. The most reactive spots for VL samples were selected, and 29 and 21 proteins were identified in the promastigote and amastigote extracts, respectively. Two of them, endonuclease III and GTP-binding protein, were cloned, expressed, purified and tested in ELISA experiments against a large serological panel, and results showed high sensitivity and specificity values for the diagnosis of disease. In conclusion, the identified proteins could be considered in future studies as candidate antigens for the serodiagnosis of human VL.


Assuntos
Antígenos de Protozoários/imunologia , Leishmania infantum/fisiologia , Leishmaniose Visceral/imunologia , Proteínas de Protozoários/imunologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteômica
10.
Parasitology ; 146(3): 322-332, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30198459

RESUMO

In the current study, phage-exposed mimotopes as targets against tegumentary leishmaniasis (TL) were selected by means of bio-panning cycles employing sera of TL patients and healthy subjects, besides the immune stimulation of peripheral blood mononuclear cells (PBMCs) collected from untreated and treated TL patients and healthy subjects. The clones were evaluated regarding their specific interferon-γ (IFN-γ) and interleukin-4 (IL-4) production in the in vitro cultures, and selectivity and specificity values were calculated, and those presenting the best results were selected for the in vivo experiments. Two clones, namely A4 and A8, were identified and used in immunization protocols from BALB/c mice to protect against Leishmania amazonensis infection. Results showed a polarized Th1 response generated after vaccination, being based on significantly higher levels of IFN-γ, IL-2, IL-12, tumour necrosis factor-α (TNF-α) and granulocyte-macrophage colony-stimulating factor (GM-CSF); which were associated with lower production of specific IL-4, IL-10 and immunoglobulin G1 (IgG1) antibodies. Vaccinated mice presented significant reductions in the parasite load in the infected tissue and distinct organs, when compared with controls. In conclusion, we presented a strategy to identify new mimotopes able to induce Th1 response in PBMCs from TL patients and healthy subjects, and that were successfully used to protect against L. amazonensis infection.


Assuntos
Leishmania mexicana/imunologia , Vacinas contra Leishmaniose/imunologia , Leishmaniose Cutânea/imunologia , Leucócitos Mononucleares/imunologia , Adulto , Animais , Bacteriófagos/imunologia , Feminino , Ensaios de Triagem em Larga Escala , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Linfócitos T/imunologia , Adulto Jovem
11.
Exp Parasitol ; 199: 30-37, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30817917

RESUMO

The treatment against leishmaniasis presents problems, since the currently used drugs are toxic and/or have high costs. In addition, parasite resistance has increased. As a consequence, in this study, a chloroquinolin derivative, namely 7-chloro-N,N-dimethylquinolin-4-amine or GF1059, was in vitro and in vivo tested against Leishmania parasites. Experiments were performed to evaluate in vitro antileishmanial activity and cytotoxicity, as well as the treatment of infected macrophages and the inhibition of infection using pre-treated parasites. This study also investigated the GF1059 mechanism of action in L. amazonensis. Results showed that the compound was highly effective against L. infantum and L. amazonensis, presenting a selectivity index of 154.6 and 86.4, respectively, against promastigotes and of 137.6 and 74.3, respectively, against amastigotes. GF1059 was also effective in the treatment of infected macrophages and inhibited the infection of these cells when parasites were pre-incubated with it. The molecule also induced changes in the parasites' mitochondrial membrane potential and cell integrity, and caused an increase in the reactive oxygen species production in L. amazonensis. Experiments performed in BALB/c mice, which had been previously infected with L. amazonensis promastigotes, and thus treated with GF1059, showed that these animals presented significant reductions in the parasite load when the infected tissue, spleen, liver, and draining lymph node were evaluated. GF1059-treated mice presented both lower parasitism and low levels of enzymatic markers, as compared to those receiving amphotericin B, which was used as control. In conclusion, data suggested that GF1059 can be considered a possible therapeutic target to be tested against leishmaniasis.


Assuntos
Antiprotozoários/farmacologia , Cloroquinolinóis/farmacologia , Leishmania infantum/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Leishmaniose Cutânea/parasitologia , Leishmaniose Visceral/parasitologia , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Anfotericina B/toxicidade , Animais , Antiprotozoários/uso terapêutico , Antiprotozoários/toxicidade , Cloroquinolinóis/uso terapêutico , Cloroquinolinóis/toxicidade , Modelos Animais de Doenças , Eritrócitos/efeitos dos fármacos , Feminino , Concentração Inibidora 50 , Leishmania infantum/crescimento & desenvolvimento , Leishmania mexicana/crescimento & desenvolvimento , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Visceral/tratamento farmacológico , Fígado/parasitologia , Linfonodos/parasitologia , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Carga Parasitária , Espécies Reativas de Oxigênio/metabolismo , Baço/parasitologia
12.
Cell Immunol ; 334: 61-69, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30287082

RESUMO

The present study evaluated the cytokine profile in PBMC supernatants and the humoral response in mucosal leishmaniasis (ML) patients and in healthy subjects living in an endemic area. Four proteins, which had previously proven to be antigenic in the human disease, were tested: LiHyM, enolase, eukaryotic initiation factor 5a, and Beta-tubulin. Results showed that all of the proteins stimulated human cells with higher IFN-γ and lower IL-4 and IL-10 levels. The analysis of antibody isotypes correlated with cell response, since the IgG2 production was higher than IgG1 in both groups. By contrast, a Th2 response was found when an antigenic Leishmania extract was used. Serological analyses revealed high sensitivity and specificity values for the serodiagnosis of the disease, when compared to the data obtained using the antigenic preparation. In conclusion, this study presents new candidates to be evaluated as biomarkers in tegumentary leishmaniasis.


Assuntos
Formação de Anticorpos/imunologia , Antígenos de Protozoários/imunologia , Leishmania/imunologia , Leishmaniose Cutânea/imunologia , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/imunologia , Adulto , Fator de Iniciação 5 em Eucariotos/imunologia , Feminino , Humanos , Imunoglobulina G/imunologia , Interferon gama/imunologia , Interleucina-10/imunologia , Interleucina-4/imunologia , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Células Th2/imunologia , Tubulina (Proteína)/imunologia , Adulto Jovem
13.
Cell Immunol ; 331: 67-77, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29871740

RESUMO

Visceral leishmaniasis (VL) is a fatal disease when acute and untreated. The treatment against this disease is long and presents toxicity and/or high costs. Moreover, parasite resistance has been increasing. Therefore, alternative control measures to avoid the spread of disease should be considered. It is accepted that the development of the T helper (Th)1 immune response, based on the production of pro-inflammatory cytokines, is required for the control of parasites. Although recombinant protein-based vaccines have been tested against VL, they require supplementation with immune adjuvants. In addition, there is a scarcity of studies that comparatively evaluate the efficacy of the immunogens when administered by different delivery systems in mammalian hosts. In the present study, a Leishmania hypothetical protein, LiHyR, was cloned and evaluated by immunization as a plasmid deoxyribonucleic acid (DNA) vaccine or in a recombinant format plus saponin against Leishmania infantum infection. Results showed that both vaccination regimens induced a Th1 cell-based immunity, since high levels of interferon-gamma (IFN-γ), interleukin (IL)-2, IL-12, granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor alpha (TNF-α) were found, and were associated with the low production of IL-4, IL-10, and anti-parasite immunoglobulin (IgG)1 isotype. In addition, significant reductions in the parasite load were found in the evaluated organs of the DNA LiHyR or rLiHyR/saponin-vaccinated animals. No significant difference was achieved between groups vaccinated with DNA or the recombinant protein. The antigen proved to be also immunogenic in human peripheral blood mononuclear cells (PBMCs) collected from healthy subjects and from untreated and treated VL patients. A higher IgG2 isotype was also found in sera samples of these subjects, thus demonstrating its possible use as a human vaccine. This study demonstrates the protective efficacy of a new Leishmania protein against VL, when it is administered as a DNA vaccine or a recombinant protein plus saponin, and points out its use as a human vaccine against disease.


Assuntos
Leishmania infantum/imunologia , Leishmaniose Visceral/imunologia , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/imunologia , Vacinas de DNA/imunologia , Adjuvantes Imunológicos/administração & dosagem , Sequência de Aminoácidos , Animais , Anticorpos Antiprotozoários/imunologia , Células Cultivadas , Citocinas/imunologia , Citocinas/metabolismo , Feminino , Humanos , Leishmania infantum/efeitos dos fármacos , Leishmania infantum/fisiologia , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/parasitologia , Camundongos Endogâmicos BALB C , Proteínas de Protozoários/genética , Proteínas Recombinantes/administração & dosagem , Homologia de Sequência de Aminoácidos , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Vacinação/métodos , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética
14.
Cell Immunol ; 323: 59-69, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29128045

RESUMO

Visceral leishmaniasis (VL) represents a serious public health problem, as Leishmania infantum is one of main disease causative agents in the Americas. In a previous immunoproteomic study, the prohibitin (PHB) protein was identified in L. infantum promastigote and amastigote extracts by antibodies in asymptomatic and symptomatic VL dog sera. This protein was found to be highly conserved between different Leishmania spp., but it presented a low identity with amino acid sequences of other organisms. The aim of the present study was to evaluate the cellular response induced by the recombinant PHB (rPHB) protein in BALB/c mice, as well as in PBMCs purified from untreated and treated VL patients, as well as to evaluate its protective efficacy against an infection by L. infantum promastigotes. Our data showed that there was a Th1 cellular response to rPHB, based on high levels of IFN-γ, IL-12, and GM-CSF in the immunized animals, as well as a proliferative response specific to the protein and higher IFN-γ levels induced in PBMCs from individuals who had recovered from the disease. The protection was represented by significant reductions in the parasite load in the animals' spleen, liver, bone marrow, and draining lymph nodes, as compared to results found in the control groups. In addition, an anti-rPHB serology, using a canine and human serological panel, showed a high performance of this protein when diagnosing VL based on high sensitivity and specificity values, as compared to results found for the rA2 antigen and the soluble Leishmania antigenic extract. Our data suggest that PHB has a potential application for the diagnosis of canine and human VL through antibody detection, as well as an application as a vaccine candidate to protect against disease.


Assuntos
Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/imunologia , Proteínas Repressoras/imunologia , Animais , Antígenos de Protozoários/imunologia , Cães , Humanos , Leishmania infantum/imunologia , Leishmania infantum/metabolismo , Leishmaniose Visceral/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Proibitinas , Proteínas Recombinantes/metabolismo , Proteínas Repressoras/metabolismo , Células Th1/imunologia , Vacinas/metabolismo
15.
Cytokine ; 111: 131-139, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30142534

RESUMO

Leishmania proteins have been evaluated as vaccine candidates against leishmaniasis; however, most antigens present low immunogenicity and need to be added with immune adjuvants. A low number of licensed adjuvants exist on the market today; therefore, research conducted to produce new products is desirable. The present study sought to evaluate the immunogenicity and protective efficacy of a recombinant Leishmania hypothetical protein, namely LiHyR, administered with saponin or liposomes in BALB/c mice. Immunological and parasitological parameters were evaluated, and results showed significant protection against Leishmania infantum infection produced by both compositions in the immunized animals; however, this was not identified when the antigen was used alone. In addition, the liposomal formulation was more effective in inducing a polarized Th1 response in the vaccinated animals, which was maintained after challenge and reflected by lower parasitism found in all evaluated organs when the limiting dilution technique and RT-PCR assay were employed. The protected animals showed higher levels of protein and parasite-specific IFN-γ IL-2, IL-12, GM-CSF, and TNF-α, which were evaluated by capture ELISA and flow cytometry, in addition to a higher production of anti-protein and anti-parasite IgG2a antibodies, both before and after challenge. The Lip/rLiHyR combination induced higher IFN-γ production through both CD4+ and CD8+ T cell subtypes. Results indicate the possibility of using the LiHyR, containing a liposomal formulation, as a vaccine candidate against visceral leishmaniasis.


Assuntos
Citocinas/imunologia , Imunogenicidade da Vacina , Leishmania infantum/imunologia , Vacinas contra Leishmaniose/farmacologia , Leishmaniose Visceral/prevenção & controle , Proteínas de Protozoários/farmacologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Vacinas contra Leishmaniose/imunologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/patologia , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Protozoários/imunologia
16.
Parasitology ; 145(6): 740-751, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29113597

RESUMO

In this study, a Leishmania hypothetical protein, LiHyS, was evaluated regarding its antigenicity, immunogenicity and protective efficacy against visceral leishmaniasis (VL). Regarding antigenicity, immunoblottings and an enzyme-linked immunosorbent assay using human and canine sera showed high sensitivity and specificity values for the recombinant protein (rLiHyS) in the diagnosis of VL. When evaluating the immunogenicity of LiHyS, which is possibly located in the parasite's flagellar pocket, proliferative assays using peripheral blood mononuclear cells from healthy subjects or VL patients showed a high proliferative index in both individuals, when compared to the results obtained using rA2 or unstimulated cultures. Later, rLiHyS/saponin was inoculated in BALB/c mice, which were then challenged with Leishmania infantum promastigotes. The vaccine induced an interferon-γ, interleukin (IL)-12 and granulocyte-macrophage colony-stimulating factor production, which was maintained after infection and which was associated with high nitrite and IgG2a antibody levels, as well as low IL-4 and IL-10 production. Significant reductions in the parasite load in liver, spleen, bone marrow and draining lymph nodes were found in these animals. In this context, the present study shows that the rLiHyS has the capacity to be evaluated as a diagnostic marker or vaccine candidate against VL.


Assuntos
Antígenos de Protozoários/imunologia , Imunogenicidade da Vacina , Leishmania infantum/imunologia , Vacinas contra Leishmaniose/imunologia , Leishmaniose Visceral/prevenção & controle , Proteínas de Protozoários/imunologia , Animais , Antígenos de Protozoários/administração & dosagem , Antígenos de Protozoários/genética , Citocinas/sangue , Cães , Feminino , Humanos , Imunoglobulina G/sangue , Interferon gama/sangue , Interleucina-12/sangue , Vacinas contra Leishmaniose/administração & dosagem , Vacinas contra Leishmaniose/genética , Leishmaniose Visceral/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Carga Parasitária , Proteínas de Protozoários/administração & dosagem , Proteínas de Protozoários/genética , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia
17.
J Nerv Ment Dis ; 206(7): 507-512, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29905661

RESUMO

The aim of this work was to investigate the association between traumatic experiences and posttraumatic stress disorder (PTSD) with the academic performance of university students. This is a one-phase study that included 2213 students, enrolled at one of seven college institutions in their first or final semesters in all programs, who filled out the self-response questionnaires. From this student population, 14% presented with PTSD, with 13.3% in their first semester and 14.9% in their final semester. The students who presented lower academic results (low scoring) had a higher prevalence of PTSD in both the first and final semesters. Nonsexual violence was related with low scoring in the first-semester students. Thus, we conclude that students in the PTSD group present worse academic performance. These results indicate a need to pay attention to students who have been through traumatic experiences and gone on to develop PTSD, to ensure their undergraduate success and enable their future performance as professionals.


Assuntos
Desempenho Acadêmico , Acontecimentos que Mudam a Vida , Transtornos de Estresse Pós-Traumáticos/psicologia , Estudantes/psicologia , Vítimas de Crime , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Autorrelato , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Inquéritos e Questionários , Universidades , Violência , Adulto Jovem
18.
Exp Parasitol ; 186: 24-35, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29448040

RESUMO

Amphotericin B (Amp) has been well-successfully used to treat against Leishmania infection, although high toxicity has been found in patients. In the present study, Amp was administered in Leishmania infantum-infected BALB/c mice by three distinct delivery systems aiming to compare their efficacy against challenge infection, as well as their side effects in a murine visceral leishmaniasis (VL) model. This product was administered in a Poloxamer P407 (Pluronic® F127)-based polymeric micelle system (Amp/M), in the Ambisome® formulation (Lip-Amp) or in a free format (free Amp). Glucantime® (Gluc) was used as a comparative drug. Aiming to evaluate different endpoints of the treatments, the efficacy of the compounds was investigated one and 15-days after the therapeutic regimens, determining the parasite load by a limiting dilution assay and a quantitative PCR (qPCR) technique, as well as evaluating the immune response generated in the infected and treated animals. In the results, Amp/M or Lip-Amp-treated mice presented the best outcomes, since significant parasite load reductions were found in the evaluated organs, as well as a parasite-specific Th1 immune response was observed in the animals. In addition, no hepatic or renal damage was found in these mice. On the other hand, free Amp or Gluc induced toxicity in the animals, which was associated with a low Th1 immune response. Comparatively, Amp/M was the most effective drug in our experimental model, and results showed that the Amp-carrying system could be considered as a future alternative in studies against VL.


Assuntos
Anfotericina B/administração & dosagem , Antiprotozoários/administração & dosagem , Sistemas de Liberação de Medicamentos/normas , Leishmaniose Visceral/tratamento farmacológico , Anfotericina B/toxicidade , Animais , Antiprotozoários/toxicidade , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Rim/efeitos dos fármacos , Leishmania infantum/efeitos dos fármacos , Fígado/efeitos dos fármacos , Meglumina/administração & dosagem , Antimoniato de Meglumina , Camundongos , Camundongos Endogâmicos BALB C , Micelas , Nitritos/metabolismo , Compostos Organometálicos/administração & dosagem , Organismos Livres de Patógenos Específicos , Baço/citologia , Baço/imunologia
19.
Int J Mol Sci ; 19(1)2018 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-29301342

RESUMO

In a proteomics approach conducted with Leishmania amazonensis, parasite proteins showed either an increase or a decrease in their expression content during extensive in vitro cultivation, and were related to the survival and the infectivity of the parasites, respectively. In the current study, a computational screening was performed to predict virulence factors among these molecules. Three proteins were selected, one of which presented no homology to human proteins. This candidate, namely small myristoylated protein-3 (SMP-3), was cloned, and its recombinant version (rSMP-3) was used to stimulate peripheral blood mononuclear cells (PBMCs) from healthy subjects living in an endemic area of leishmaniasis and from visceral leishmaniasis patients. Results showed high interferon-γ (IFN-γ) production and low levels of interleukin 10 (IL-10) in the cell supernatants. An in vivo experiment was then conducted on BALB/c mice, which were immunized with rSMP-3/saponin and later challenged with Leishmania infantum promastigotes. The rSMP-3/saponin combination induced high production of protein-specific IFN-γ, IL-12, and granulocyte-macrophage colony-stimulating factor (GM-CSF) by the spleen cells of the immunized mice. This pattern was associated with protection, which was characterized by a significant reduction in the parasite load in distinct organs of the animals. Altogether, these results have revealed that this new virulence factor is immunogenic in both mice and humans, and have proven its protective efficacy against visceral leishmaniasis in a murine model.


Assuntos
Antígenos de Protozoários/metabolismo , Leishmania/patogenicidade , Leishmaniose Visceral/prevenção & controle , Leishmaniose Visceral/parasitologia , Proteínas de Protozoários/metabolismo , Fatores de Virulência/metabolismo , Sequência de Aminoácidos , Animais , Antígenos de Protozoários/química , Biologia Computacional , Citocinas/metabolismo , Epitopos de Linfócito T/metabolismo , Humanos , Imunidade Celular , Imunidade Humoral , Leishmania infantum , Leishmaniose Visceral/imunologia , Leucócitos Mononucleares/metabolismo , Modelos Lineares , Camundongos Endogâmicos BALB C , Anotação de Sequência Molecular , Proteínas de Protozoários/química , Reprodutibilidade dos Testes , Homologia Estrutural de Proteína
20.
Rev Gaucha Enferm ; 39: e65127, 2018 Jul 23.
Artigo em Português, Inglês | MEDLINE | ID: mdl-30043951

RESUMO

OBJECTIVE: To evaluate the occupational stress among health workers in a university hospital. METHODS: Cross-sectional study conducted with health workers in the areas of nursing and medicine at a university hospital in southern Brazil. The data were collected between August of 2011 and August of 2012 by a questionnaire of characterization and Job Stress Scale. A descriptive and univariate analysis was performed (Kruskal-Wallis). RESULTS: The participants presented high demand and high control of the work and low social support, indicating an active work. Nurses had less control over work (p<0.001) and physicians received more social support (p=0.006). Reduced social support was related to greater exposure to stress among nursing assistants and technicians (p=0.012). CONCLUSION: Workers who felt the low social support had higher exposure to stress. It is necessary to implement stress prevention strategies among health workers, such as the strengthening of social support at work.


Assuntos
Hospitais Universitários , Recursos Humanos em Hospital/psicologia , Adulto , Idoso , Brasil , Estudos Transversais , Feminino , Hábitos , Humanos , Masculino , Corpo Clínico Hospitalar/psicologia , Pessoa de Meia-Idade , Assistentes de Enfermagem/psicologia , Recursos Humanos de Enfermagem Hospitalar/psicologia , Exposição Ocupacional , Estresse Ocupacional/epidemiologia , Estresse Ocupacional/psicologia , Índice de Gravidade de Doença , Apoio Social , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
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