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1.
Planta Med ; 89(5): 539-550, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36720229

RESUMO

This study evaluates the pharmacological potential of cis-jasmone (CJ) in adult zebrafish (Danio rerio; aZF). Initially, aZF (n = 6/group) were pretreated (20 µL; p. o.) with CJ (0.1 or 0.3 or 1.0 mg/mL) or vehicle (0.5% Tween 80). The animals were submitted to acute toxicity and locomotion tests, pentylenetetrazole-induced seizure, carrageenan-induced abdominal edema, and cinnamaldehyde-, capsaicin-, menthol-, glutamate-, and acid saline-induced orofacial nociception. The possible mechanisms of anticonvulsant, anxiolytic, and antinociceptive action were evaluated. The involvement of central afferent fibers sensitive to cinnamaldehyde and capsaicin and the effect of CJ on the relative gene expression of TRPA1 and TRPV1 in the brain of aZF were also analyzed, in addition to the study of molecular docking between CJ and TRPA1, TRPV1 channels, and GABAA receptors. CJ did not alter the locomotor behavior and showed pharmacological potential in all tested models with no toxicity. The anticonvulsant effect of CJ was prevented by flumazenil (GABAergic antagonist). The anxiolytic-like effect of CJ was prevented by flumazenil and serotonergic antagonists. The antinociceptive effect was prevented by TRPA1 and TRPV1 antagonists. Chemical ablation with capsaicin and cinnamaldehyde prevented the orofacial antinociceptive effect of CJ. Molecular docking studies indicate that CJ interacted with TRPA1, TRPV1, and GABAA receptors. CJ inhibited the relative gene expression of TRPA1 and TRPV1. CJ has pharmacological potential for the treatment of seizures, anxiety, inflammation, and acute orofacial nociception. These effects are obtained by modulating the GABAergic and serotonergic systems, as well as the TRPs and ASIC channels.


Assuntos
Analgésicos , Ansiolíticos , Animais , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Peixe-Zebra/metabolismo , Capsaicina/farmacologia , Simulação de Acoplamento Molecular , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Flumazenil , Ácido gama-Aminobutírico , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo
2.
AAPS PharmSciTech ; 23(7): 239, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36002707

RESUMO

Nanoencapsulation is a valid alternative for the oral administration of peptide drugs and proteins, as nanoparticles protect them from proteolytic degradation in the gastrointestinal tract and promote the absorption of these macromolecules. The orofacial antinociceptive effect of frutalin (FTL), through the intraperitoneal route, has already been proven. This study aimed to develop, characterize, and evaluate the orofacial antinociceptive activity of an oral formulation containing FTL in acute and neuropathic preclinical tests. Nanoencapsulated FTL was administered by oral route. The acute nociceptive behavior was induced by administering capsaicin to the upper lip and NaCl to the right cornea. The nociceptive behavior was also induced by formalin injected into the temporomandibular joint. The neuropathic pain model involved infraorbital nerve transection (IONX), which induced mechanical hypersensitivity and was assessed by von Frey stimulation. Trpv1 gene expression was analyzed in the trigeminal ganglion. The analyzed sample did not show any cytotoxicity; 52.2% of the FTL was encapsulated, and the size of the nanocapsule was less than 200 nm, the polydispersion was 0.361, and the zeta potential was - 5.87 and - 12.8 mV, with and without FTL, respectively. Nanoencapsulated FTL administered by oral route had an orofacial antinociceptive effect in acute and neuropathic rodent models. The antinociceptive effect of FTL was prevented by ruthenium red, but not by camphor. FTL reduced Trpv1 gene expression. FTL promotes orofacial antinociception, probably due to the antagonism of TRPV1 channels, and the nanoformulation represents an effective method for the oral administration of this protein. HIGHLIGHTS: • Nanoformulation for oral protein administration. • Nanocapsule containing FTL prevents orofacial nociceptive acute and neuropathic pain. • Frutalin promotes orofacial antinociception behavior antagonism of TRPV1 channels.


Assuntos
Nanocápsulas , Neuralgia , Administração Oral , Analgésicos , Animais , Modelos Animais de Doenças , Dor Facial/tratamento farmacológico , Dor Facial/metabolismo , Nociceptividade/fisiologia
3.
Sci Rep ; 11(1): 18380, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526543

RESUMO

The imprinted H19 long non-coding RNA, a knowing oncofetal gene, presents a controversial role during the carcinogenesis process since its tumor suppressor or oncogenic activity is not completely elucidated. Since H19 lncRNA is involved in many biological pathways related to tumorigenesis, we sought to develop a non-cancer lineage with CRISPR-Cas9-mediated H19 knockdown (H19-) and observe the changes in a cellular context. To edit the promoter region of H19, two RNA guides were designed, and the murine C2C12 myoblast cells were transfected. H19 deletion was determined by DNA sequencing and gene expression by qPCR. We observed a small deletion (~ 60 bp) in the promoter region that presented four predicted transcription binding sites. The deletion reduced H19 expression (30%) and resulted in increased proliferative activity, altered morphological patterns including cell size and intracellular granularity, without changes in viability. The increased proliferation rate in the H19- cell seems to facilitate chromosomal abnormalities. The H19- myoblast presented characteristics similar to cancer cells, therefore the H19 lncRNA may be an important gene during the initiation of the tumorigenic process. Due to CRISPR/Cas9 permanent edition, the C2C12 H19- knockdown cells allows functional studies of H19 roles in tumorigenesis, prognosis, metastases, as well as drug resistance and targeted therapy.


Assuntos
Sistemas CRISPR-Cas , Neoplasias/genética , Neoplasias/patologia , Regiões Promotoras Genéticas , RNA Longo não Codificante/genética , Deleção de Sequência , Animais , Sequência de Bases , Biomarcadores Tumorais , Carcinogênese/genética , Ciclo Celular/genética , Proliferação de Células/genética , Análise Citogenética , Edição de Genes , Técnicas de Silenciamento de Genes , Humanos , Camundongos , RNA Longo não Codificante/química
4.
Int J Biometeorol ; 65(12): 2147-2155, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34402987

RESUMO

The present study evaluated the general welfare state of two strains of transgenic goats bred in a region with a hot and humid tropical climate. Nine females were used, being three transgenic for human lysozyme (hLZ group), three transgenic for human glucocerebrosidase (hGCase group), and three non-transgenic (control group). The temperature and humidity index (THI) were recorded during the morning, afternoon, and evening. The physiological parameters measured were respiratory rate, heart rate, and rectal and vaginal temperatures. Venous blood samples were collected using Vacutainer® tubes containing 10% ethylenediaminetetraacetic acid (EDTA). Also, analysis of erythrogram, leukogram, and some biochemical parameters of serum was performed. It was observed that the afternoon shift presented the largest THI, being potentially more impactful on the physiology of animals. In general, respiratory and heart rates were higher in transgenic animals, especially in the hLZ group compared to the control group (P < 0.05). Regarding the hematological parameters, the quantification of red blood cells, hemoglobin, and hematocrit was significantly lower (P < 0.05) in the hGCase group compared to that in the hLZ and control. The leukocyte count was considerably lower (P < 0.05) in the hLZ group compared to that in the hGCase and control. Correlation analysis showed that the increase in THI was associated with a change in physiological parameters normally used as indicators of thermal stress. Despite the differences found among the experimental groups, all the physiological parameters remained within the normal limits recommended for the goat species. Further studies involving a larger number of animals from different categories should be carried out to elucidate the impacts that transgenesis can have on animal welfare under different THI conditions.


Assuntos
Cabras , Clima Tropical , Animais , Animais Geneticamente Modificados , Feminino , Cabras/genética , Temperatura Alta , Umidade , Temperatura
5.
Rev Soc Bras Med Trop ; 53: e20200657, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33263691

RESUMO

INTRODUCTION: Quantitative reverse transcription polymerase chain reaction (RT-qPCR) can detect the severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) in a highly specific manner. However, a decrease in the specificity of PCR assays for their targets may lead to false negative results. METHODS: Here, 177 high-coverage complete SARS-CoV-2 genome sequences from 13 Brazilian states were aligned with 15 WHO recommended PCR assays. RESULTS: Only 3 of the 15 completely aligned to all Brazilian sequences. Ten assays had mismatches in up to 3 sequences and two in many sequences. CONCLUSION: These results should be taken into consideration when using PCR-based diagnostics in Brazil.


Assuntos
COVID-19/virologia , Genoma Viral , SARS-CoV-2/genética , Brasil , Simulação por Computador , Humanos , Pandemias , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade
6.
PLoS One ; 15(9): e0239435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946490

RESUMO

The genotyping of genetically-modified cells is a crucial step in studies of transgenics and genomic editing with systems such as CRISPR/Cas. The detection of genome editing events can be directly related to the genotyping methodology used, which is influenced by its costs, since many experiments require the analysis of a large number of samples. The aim of this study was to compare the performance of direct lysis methods of genomic DNA (gDNA) extraction for the detection of knockins and knockouts in primary goat cells. Initially, three gDNA extraction protocols (protocol A, heat denaturation/freeze-thaw in water; protocol B, heat denaturation/proteinase K; and protocol C, CellsDirect Kit) were tested using different quantities (1,000, 5,000 and 10,000 cells) and types of goat primary cells (fibroblasts and goat mammary epithelial cells-GMECs) for subsequent validation by PCR amplification of small (GAPDH) and large amplicons (hLF transgene). All protocols were successful in the detection of the small amplicon; however, in GMECs, only protocol B resulted efficient amplification (protocol A-0%, protocol B-93%, protocol C-13.33%, P <0.05). In a proof-of-principle experiment, the TP53 gene was knocked out in GMECs by CRISPR/Cas9-mediated deletion while constructs containing the anti-VEGF monoclonal antibody (pBC-anti-VEGF) and bacterial L-Asparaginase (pBC-ASNase) transgenes were knocked-in separately in fibroblasts. Detection of successful editing was performed using protocol B and PCR. The integration rates of the pBC-ASNase and pBC-anti-VEGF transgenes were 93.6% and 72%, respectively, as per PCR. The efficiency of biallelic editing in GMECs using CRISPR/Cas9 for the TP53 deletion was 5.4%. Our results suggest that protocol B (heat denaturation/proteinase K) can be used as an inexpensive and quick methodology for detecting genetic modifications in different types of primary goat cells, with efficiency rates consistent with values previously described in the literature when using extraction kits or more complex proteinase K formulations.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Análise Custo-Benefício , DNA/genética , DNA/isolamento & purificação , Edição de Genes , Transgenes/genética , Animais , Sequência de Bases , Fibroblastos/citologia , Fibroblastos/metabolismo , Cabras
7.
Rev. Ciênc. Méd. Biol. (Impr.) ; 19(2): 305-310, set 24, 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1358273

RESUMO

Introduction: breast cancer (BC) is the most common tumor and the leading cause of cancer-related death among the female population worldwide. Polymorphisms genetics of ABCB1 gene contributed to breast cancer susceptibility and interindividual differences in chemotherapy response. Objectives: to evaluate the association between the ABCB1 C3435T gene polymorphism (SNPs) with the response to neoadjuvant chemotherapy in women with breast cancer. Methodology: this study included 32 female patients who received neoadjuvant chemotherapy. The polymorphisms were genotyped through real-time allele-specific polymerase chain reaction (PCR). The statistical analysis was performed using the Fisher's exact test or Pearson's chi-square test in the Statistical Package for Social Sciences (SPSS) version 20.0 software. Results: the genotypes found for the C3435T polymorphism were in Hardy-Weinberg equilibrium and their genotypic distributions were CC= 10 (31.1%), CT= 14 (43.8%), and TT= 08 (25.0%) with χ2: 0.86 and p-value > 0.05. Allele frequencies were C = 0.54 and T = 0.46. There were no significant statistical differences between genotypes considering the response to neoadjuvant chemotherapy and immunohistochemistry; the presence of the T allele was associated with worsen axillary status response to neoadjuvant chemotherapy. Conclusion: no definite association between the presence of C3435T polymorphism and the response to neoadjuvant chemotherapy was observed. Further studies in Brazil involving larger samples will contribute to validating the results of this study.


Introdução: o câncer de mama (CM) é o tumor mais comum e a principal causa de morte relacionada ao câncer na população feminina em todo o mundo. Polimorfismos genéticos do gene ABCB1 contribuem para a suscetibilidade ao câncer de mama e diferenças interindividuais na resposta à quimioterapia. Objetivos: avaliar a associação entre o polimorfismo (SNPs) do gene ABCB1 C3435T com a resposta à quimioterapia neoadjuvante em mulheres com câncer de mama. Metodologia: estudo com 32 pacientes do sexo feminino, que utilizaram quimioterapia neoadjuvante. A genotipagem dos polimorfismos foi feita por reação da polimerase em cadeia (PCR) em tempo real alelo específica. A análise estatística foi realizada mediante o teste exato de Fisher ou Qui-quadrado de Pearson, utilizando o software SPSS (Statistical Package for the Social Sciences) vs20.0. Resultados: os genótipos encontrados para o polimorfismo C3435T estavam em equilíbrio de Hardy-Weinberg e suas distribuições genotípicas foram respectivamente CC= 10 (31,1%), CT= 14 (43,8%), TT= 08 (25,0%) sendo, X2: 0.86 e p-value> 0,05. As frequências alélicas foram de C= 0,54 e T= 0,46. Não ocorreram diferenças estatísticas entre os genótipos, considerando a resposta a quimioterapia neoadjuvante e a imunohistoquímica, sendo a presença do alelo T associada a pior resposta do status axilar à quimioterapia neoadjuvante. Conclusão: não foi possível correlacionar a presença do polimorfismo C3435T com a resposta à quimioterapia neoadjuvante, sendo necessária a realização de novos estudos no Brasil envolvendo casuísticas maiores para a validação dos resultados.


Assuntos
Humanos , Feminino , Polimorfismo Genético , Neoplasias da Mama , Tratamento Farmacológico , Estudos Prospectivos , Estudo Observacional
8.
Rev. Soc. Bras. Med. Trop ; 53: e20200657, 2020. tab, graf
Artigo em Inglês | Sec. Est. Saúde SP, Coleciona SUS, LILACS | ID: biblio-1143868

RESUMO

Abstract INTRODUCTION: Quantitative reverse transcription polymerase chain reaction (RT-qPCR) can detect the severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) in a highly specific manner. However, a decrease in the specificity of PCR assays for their targets may lead to false negative results. METHODS: Here, 177 high-coverage complete SARS-CoV-2 genome sequences from 13 Brazilian states were aligned with 15 WHO recommended PCR assays. RESULTS: Only 3 of the 15 completely aligned to all Brazilian sequences. Ten assays had mismatches in up to 3 sequences and two in many sequences. CONCLUSION: These results should be taken into consideration when using PCR-based diagnostics in Brazil.


Assuntos
Humanos , Genoma Viral , Infecções por Coronavirus/virologia , Betacoronavirus/genética , Simulação por Computador , Brasil , RNA Viral/genética , Sensibilidade e Especificidade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pandemias
9.
BMC Res Notes ; 12(1): 794, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806048

RESUMO

OBJECTIVE: L-Asparaginase (ASNase) is an enzyme used in the treatment of acute lymphoblastic leukemia (ALL). As the therapeutic ASNases has bacterial origin, severe side effects are associated with its use, among them hypersensitivity and inactivation of the enzyme. In this context, the objective of this work was to produce a recombinant ASNase of bacterial origin in human cells in order to determine the presence and consequences of potential post-translational modifications on the enzyme. RESULTS: Recombinant ASNase was expressed in human cells with a molecular weight of 60 kDa, larger than in Escherichia coli, which is 35 kDa. N-glycosylation analysis demonstrated that the increased molecular weight resulted from the addition of glycans to the protein by mammalian cells. The glycosylated ASNase presented in vitro activity at physiological pH and temperature. Given that glycosylation can act to reduce antigenicity by masking protein epitopes, our data may contribute to the development of an alternative ASNase in the treatment of ALL in patients who demonstrate side effects to currently marketed enzymes.


Assuntos
Asparaginase/genética , Escherichia coli/enzimologia , Asparaginase/metabolismo , Clonagem Molecular , Escherichia coli/genética , Glicosilação , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Temperatura
10.
Zygote ; 26(5): 350-358, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30289102

RESUMO

SummaryThe objectives were to develop an effective protocol for transfection of ovine secondary follicles and to assess the effect of attenuating aquaporin 3 (AQP3) using a small interfering RNA (siRNA-AQP3) on antrum formation and follicular growth in vitro. Various combinations of Lipofectamine® volumes (0.5, 0.75 or 1.0 µl), fluorescent oligonucleotide (BLOCK-iT ™) concentrations (3.18, 27.12 or 36.16 nM) and exposure times (12, 14, 16, 18 or 20 h) were tested. The BLOCK-iT™ was replaced by siRNA-AQP3 in the transfection complex. Ovine secondary follicles were isolated and cultured in vitro for 6 days using standard protocols. Follicles were transfected on day 0 or 3 or on both days (0 and 3) and then cultured for an additional 3 or 6 days. As revealed by the fluorescence signal, the Lipofectamine®/BLOCK-iT™ complex (0.75 µl + 27.12 nM by 12 h of incubation) crossed the basement membrane and granulosa cell and reached the oocytes. In general, the rate of intact follicles was higher and the rate of antrum formation was lower in transfected follicles compared with control follicles. In conclusion, ovine secondary follicles can be successfully transfected during in vitro culture, and siRNA-mediated attenuation of AQP3 gene reduced antrum formation of secondary follicles.


Assuntos
Aquaporina 3/genética , Folículo Ovariano/fisiologia , Transfecção/métodos , Animais , Aquaporina 3/metabolismo , Técnicas de Cultura de Células , Feminino , Técnicas de Silenciamento de Genes , Lipídeos , Folículo Ovariano/crescimento & desenvolvimento , Interferência de RNA , Ovinos
11.
Cell Tissue Res ; 372(3): 611-620, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29488001

RESUMO

The multidrug resistance proteins ABCB1, ABCC2 and ABCG2 are an energy-dependent efflux pump that functions in systemic detoxification processes. Physiologically expressed in a variety of tissues, most abundantly in the liver and intestinal epithelia, placenta, blood-brain barrier and various stem cells, until now, these pumps were not identified in goat ovarian tissue. Therefore, the aim of this study is to analyze ABCB1, ABCC2, and ABCG2 mRNA and protein expression in goat preantral follicles. Fragments (3 × 3 × 1 mm) from five pairs of ovary (n = 10) obtained from five goat were collected and immediately submitted to qPCR, Western blot, and immunofluorescence assay for mRNA detection and identification and localization of the ABC transporters, respectively. mRNA for ABCB1, ABCC2, and ABCG2 and the presence of their proteins were observed on ovarian tissue samples. Positive marks were observed for the three transport proteins in all follicular categories studied. However, the marks were primarily localized in the oocyte of primordial, transition and primary follicle categories. In conclusion, goat ovarian tissue expresses mRNA for the ABCB1, ABCC2 and ABCG2 transporters and the expression of these proteins in the preantral follicles is a follicle-dependent stage.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Regulação da Expressão Gênica , Cabras/genética , Folículo Ovariano/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Feminino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Coloração e Rotulagem
12.
Cell Reprogram ; 18(4): 264-79, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27362734

RESUMO

Cloning by somatic cell nuclear transfer (SCNT) is characterized by low efficiency and the occurrence of developmental abnormalities, which are rather poorly studied phenomena in goats. This study aimed at comparing overall SCNT efficiency in goats by using in vitro-matured (IVM) or in vivo-matured oocytes and fibroblast donor cells (mock transfected, transgenic, or wild type), also characterizing symptoms of the Abnormal Offspring Syndrome (AOS) in development, comparing results with pregnancies produced by artificial insemination (AI) and in vivo-derived (IVD) embryos. The SCNT group had lower pregnancy rate (18.3%, 11/60), total number of concepti (20.0%, 12/60), term births (3.3%, 2/60), and live births (1.7%, 1/60) than both the IVD (77.8%, 7/9; 155.5%, 14/9; 122.2%, 11/9; 88.8%, 8/9) and the AI (71.4%, 10/14; 121.4%, 17/14; 100%, 14/14; 78.5%, 11/14) groups, respectively (p < 0.05). No SCNT pregnancies reached term using IVM oocytes, but in vivo-matured oocytes resulted in two term transgenic cloned kids. The proportion fetal membrane (FM) weight/birth weight reflected an increase in FM size and cotyledonary enlargement in clones, for disproportionally bigger newborns in relation to cotyledonary numbers. Overall, goat cloning showed losses and abnormality patterns similar to the AOS in cloned cattle and sheep, which have not been previously well recognized in goats.


Assuntos
Animais Geneticamente Modificados/crescimento & desenvolvimento , Transferência Embrionária/veterinária , Desenvolvimento Embrionário , Fibroblastos/citologia , Técnicas de Transferência Nuclear/veterinária , Oócitos/citologia , Animais , Animais Geneticamente Modificados/genética , Animais Recém-Nascidos , Feminino , Fibroblastos/metabolismo , Cabras , Oócitos/metabolismo , Gravidez , Taxa de Gravidez , Nascimento a Termo
13.
Mol Biotechnol ; 58(1): 47-55, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26589705

RESUMO

Gaucher disease (GD) is an orphan disease characterized by the lack or incapacity of glucocerebrosidase (hGCase) to properly process glucosylceramide, resulting in its accumulation in vital structures of the human body. Enzyme replacement therapy supplies hGCase to GD patients with a high-cost recombinant enzyme produced in vitro in mammalian or plant cell culture. In this study, we produced hGCase through the direct injection of recombinant adenovirus in the mammary gland of a non-transgenic goat. The enzyme was secreted in the milk during six days at a level up to 111.1 ± 8.1 mg/L, as identified by mass spectrometry, showing high in vitro activity. The milk-produced hGCase presented a mass correspondent to the intermediary high-mannose glycosylated protein, which could facilitate its delivery to macrophages through the macrophage mannose receptor. Further studies are underway to determine the in vivo delivery capacity of milk-hGCase, but results from this study paves the way toward the generation of transgenic goats constitutively expressing hGCase in the milk.


Assuntos
Terapia de Reposição de Enzimas , Doença de Gaucher/genética , Glucosilceramidase/biossíntese , Proteínas Recombinantes/administração & dosagem , Adenoviridae/genética , Animais , Feminino , Doença de Gaucher/enzimologia , Doença de Gaucher/patologia , Glucosilceramidase/administração & dosagem , Glucosilceramidase/genética , Glucosilceramidas/metabolismo , Cabras/genética , Humanos , Glândulas Mamárias Animais/enzimologia , Leite/metabolismo
14.
Vet Parasitol ; 168(1-2): 1-4, 2010 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-19939570

RESUMO

Around 1900 Laveran and Mesnil discovered that African trypanosomes do not survive in the blood of some primates and humans. The nature of the trypanolytic factor present in these sera has been the focus of a long-standing debate between different groups. The aim of this study was to investigate the susceptibility of T. evansi isolates to therapy using human blood and plasma in experimentally infected mice. Forty-eight 2-month-old female mice (Mus musculus) were divided into six groups of eight animals per group (A, B, C, D, E and F). Plasma was obtained after blood collection in order to perform therapy. Animals from group A (positive control) were inoculated with T. evansi and treated with 0.2mL of saline solution. Animals from groups B and C were infected with the flagellate and received a curative treatment with 0.2mL of human blood (group B) and 0.2mL of human plasma (group C), 24h after infection. Animals from groups D and E received a prophylactic treatment with 0.2mL of human blood and 0.2mL of human plasma, respectively, 24h prior to the infection. Animals from group F (negative control) were not infected and received 0.2mL of saline solution. The four treatments (B, C, D and E) increased animals longevity when compared to group A. Prepatency period was longer in groups D (15 days) and E (37.7 days) under prophylactic immunotherapy. Moreover, no parasites were found in most of the animals 60 days post-inoculation (PI). Besides the longer longevity, treatments were capable of curing 50% of mice of group B, 37.5% of group C, 37.5% of group D and 25% of the animals from group E.


Assuntos
Sangue , Plasma , Trypanosoma/fisiologia , Tripanossomíase/parasitologia , Tripanossomíase/terapia , Animais , Sangue/parasitologia , Feminino , Humanos , Camundongos , Análise de Sobrevida , Tripanossomicidas/administração & dosagem , Tripanossomíase/mortalidade
15.
Ciênc. rural ; 39(6): 1842-1846, set. 2009. tab
Artigo em Português | LILACS | ID: lil-525282

RESUMO

O objetivo deste estudo foi investigar a patogenicidade do isolado de Trypanosoma evansi (LPV-2005), em ratos (Rattus norvergicus), sob influência da imunidade passiva, de diferentes concentrações e de meios de conservação. Para tanto, foram utilizados 36 Rattus norvergicus, fêmeas, separados em seis grupos homogêneos. Os roedores dos grupos A e B foram infectados com 10(5) T. evansi, e os animais dos grupos C e D foram infectados com 10(6) tripomastigotas/animal. Os grupos E e F foram utilizados como grupo controle negativo, isto é, inoculados com sangue in natura e criopreservado sem o parasito, respectivamente. O grupo A foi formado por ratos filhos de fêmeas infectadas com protozoário, mas curadas após tratamento. Os grupos B, C e D continham roedores que nunca tiveram contato com o isolado LPV-2005. Os grupos B e C diferiram quanto à dose inoculada do flagelado mantida em cultura viva (ratos Wistar). Já os ratos do grupo D foram infectados com sangue criopreservado em nitrogênio líquido. A patogenicidade do isolado foi avaliada a partir do período pré-patente, da evolução da parasitemia e da longevidade dos animais. O grupo D apresentou um período pré-patente superior aos demais grupos. Em relação à longevidade dos animais de cada grupo, foi verificada diferença estatística significativa (P<0,05). O grupo D apresentou um período de vida de 27,8 dias, e o grupo C, de apenas 4,8 dias. Os ratos de ambos os grupos controle mantiveram-se vivos por 50 dias, quando foram eutanasiados. Portanto, a preservação do inóculo testado e a dose infectante de T. evansi influenciam a patogenicidade do isolado LPV-2005 para ratos. A presença de anticorpos maternos em ratos não impede a infecção e mortalidade por T. evansi.


This study aimed to evaluate the Trypanosoma evansi strain pathogenicity (LPV-2005) in rats under passive immunity influence, of different concentrations and media preservation. Thirty six adult female Rattus norvergicus were separated in six equal groups. Groups A and B were inoculated with 10(5) T. evansi and groups C and D with 10(6) blood trypomastigotes per animal. Groups E and F were used as negative control in which the animals were inoculated with fresh and cryopreserved blood, without the parasite. Group A were composed of T. evansi infected born rats and cured females. Groups B, C and D were composed with animals never exposed to the LPV-2005 strain. All groups B and C animals received different doses of blood trypomastigotes kept in Wistar rats, while animals from group D were infected with cryopreserved blood kept in liquid nitrogen. The the strain pathogenicity was estimated by prepatency evaluation period, levels of parasitemia and animals longevity. Group D showed a longer prepatency period in comparison with other groups. The longevity of group D (27.8 days) was significantly different (P<0.05) from group C (4.8 days). Rats of the control group were euthanized 50 days postinfection. In conclusion, the tested inoculum-preservation methods and the infective dose of T. evansi influenced the pathogenicity of the LPV-2005 strain in rats. The presence of maternal antibodies did not prevent the infection and mortality of the rats by T. evansi.

16.
Rev Soc Bras Med Trop ; 41(4): 421-3, 2008.
Artigo em Português | MEDLINE | ID: mdl-18853021

RESUMO

In response to complaints of the presence of triatomines in a fishing hut on the banks of the Caveiras river, in the municipality of São José do Cerrito, State of Santa Catarina, an investigation was conducted in this hut and in other ecotopes neighboring the initial finding. Fifteen specimens of Panstrongylus megistus were found and none of them were infected. The locality of this ecotope is visited occasionally by capybaras, opossums, armadillos and rats.


Assuntos
Habitação , Insetos Vetores , Panstrongylus , Animais , Brasil , Masculino
17.
Rev. Soc. Bras. Med. Trop ; 41(4): 421-423, jul.-ago. 2008. ilus, mapas
Artigo em Português | LILACS | ID: lil-494503

RESUMO

Em resposta a uma denúncia da existência de triatomíneos em uma cabana de pesca as margens do Rio Caveiras no município de São José do Cerrito-SC, foi feita a investigação na cabana e em outros ecótopos vizinhos ao achado inicial. Foram encontrados 15 exemplares de Panstrongylus megistus sendo que nenhum deles encontrava-se infectado. O local do ecótopo é visitado ocasionalmente por capivaras, gambás, tatus e ratos.


In response to complaints of the presence of triatomines in a fishing hut on the banks of the Caveiras river, in the municipality of São José do Cerrito, State of Santa Catarina, an investigation was conducted in this hut and in other ecotopes neighboring the initial finding. Fifteen specimens of Panstrongylus megistus were found and none of them were infected. The locality of this ecotope is visited occasionally by capybaras, opossums, armadillos and rats.


Assuntos
Animais , Masculino , Habitação , Insetos Vetores , Panstrongylus , Brasil
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