Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 117
Filtrar
1.
Parasit Vectors ; 13(1): 570, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33176846

RESUMO

BACKGROUND: Rattus spp. are frequently implicated as key reservoir hosts for leptospirosis, one of the most common, but neglected, bacterial zoonoses in the world. Although leptospirosis is predicted to be a significant public health threat in Africa, studies from the continent are limited. METHODS: Rattus spp. (n = 171) were sampled (January-May 2016) across the City of Johannesburg, South Africa's largest inland metropole. Rattus spp. genetic diversity was evaluated by full length (1140 bp) cyt b sequencing of 42 samples. For comparison, a further 12 Rattus norvegicus samples collected in Cape Town, South Africa's largest coastal metropole, were also genotyped. Leptospira infections were identified and genotyped using real-time PCR and multi-locus (lfb1, secY and lipL41) DNA sequencing. RESULTS: Five R. norvegicus haplotypes were identified across Johannesburg, four of which have not previously been detected in South Africa, and one in Cape Town. Across Johannesburg we identified a Leptospira spp. infection prevalence of 44% (75/171) and noted significant differences in the prevalence between administrative regions within the metropole. Multi-locus sequence analyses identified a clonal genotype consistent with L. borgpetersenii serogroup Javanica (serovar Ceylonica). DISCUSSION: The prevalence of infection identified in this study is amongst the highest detected in Rattus spp. in similar contexts across Africa. Despite the complex invasion history suggested by the heterogeneity in R. norvegicus haplotypes identified in Johannesburg, a single L. borgpetersenii genotype was identified in all infected rodents. The lack of L. interrogans in a rodent community dominated by R. norvegicus is notable, given the widely recognised host-pathogen association between these species and evidence for L. interrogans infection in R. norvegicus in Cape Town. It is likely that environmental conditions (cold, dry winters) in Johannesburg may limit the transmission of L. interrogans. Spatial heterogeneity in prevalence suggest that local factors, such as land use, influence disease risk in the metropole. CONCLUSIONS: In South Africa, as in other African countries, leptospirosis is likely underdiagnosed. The high prevalence of infection in urban rodents in Johannesburg suggest that further work is urgently needed to understand the potential public health risk posed by this neglected zoonotic pathogen.


Assuntos
Leptospira/genética , Leptospirose/microbiologia , Doenças dos Roedores/microbiologia , Animais , Cidades/epidemiologia , Reservatórios de Doenças/microbiologia , Genótipo , Haplótipos , Humanos , Leptospira/classificação , Leptospirose/epidemiologia , Tipagem de Sequências Multilocus , Prevalência , Ratos/classificação , Ratos/genética , Doenças dos Roedores/epidemiologia , Análise de Sequência de DNA , Sorogrupo , África do Sul/epidemiologia , Zoonoses/epidemiologia , Zoonoses/microbiologia
2.
J Hered ; 111(4): 392-404, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32485737

RESUMO

Tropical mountains are cradles of biodiversity and endemism. Sundaland, tropical Southeast Asia, hosts 3 species of Rattus endemic to elevations above 2000 m with an apparent convergence in external morphology: Rattus korinchi and R. hoogerwerfi from Sumatra, and R. baluensis from Borneo. A fourth one, R. tiomanicus, is restricted to lowland elevations across the whole region. The origins of these endemics are little known due to the absence of a robust phylogenetic framework. We use complete mitochondrial genomes from the 3 high altitude Rattus, and several related species to determine their relationships, date divergences, reconstruct their history of colonization, and test for selection on the mitochondrial DNA. We show that mountain colonization happened independently in Borneo (<390 Kya) and Sumatra (~1.38 Mya), likely from lowland lineages. The origin of the Bornean endemic R. baluensis is very recent and its genetic diversity is nested within the diversity of R. tiomanicus. We found weak evidence of positive selection in the high-elevation lineages and attributed the greater nonsynonymous mutations on these branches (specially R. baluensis) to lesser purifying selection having acted on the terminal branches in the phylogeny.


Assuntos
Evolução Biológica , Genoma Mitocondrial , Filogenia , Ratos/genética , Altitude , Animais , Bornéu , DNA Mitocondrial/genética , Indonésia , Ratos/classificação , Seleção Genética
3.
Zootaxa ; 4459(3): 431-452, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30314119

RESUMO

The murid rodent genus Rattus Fischer 1803 contains several species that are responsible for massive loss of crops and food, extinction of other species and the spread of zoonotic diseases to humans, as well as a laboratory species used to answer important questions in physiology, immunology, pharmacology, toxicology, nutrition, behaviour and learning. Despite the well-known significant impacts of Rattus, a definitive evolutionary based systematic framework for the genus is not yet available. The past 75 years have seen more dramatic changes in membership of Rattus than in almost any other genus of mammals. In fact, the Rattus genus has been a receptacle for any generalised Old World murine that lacked morphological specialisation and at one point, has included more than 560 species and/or subspecies, spread across Eurasia, Africa and the Australo-Papuan region. The dissolution of Rattus is ongoing as many of its constituent species and many genera of Rattini remain unsampled in any molecular study. To address this sampling limitation, we sequenced the mitochondrial cytochrome b (cytb) gene and examined phylogenetic relationships using both Bayesian and Maximum Likelihood algorithms for an expanded set of taxa within Rattus and among closely related genera. Here we place previously unsampled taxa in a phylogenetic context for the first time, including R. burrus, R. hoogerwerfi, R. lugens, and R. mindorensis within the Asian Rattus group, R. facetus within the Australo-Papuan Rattus radiation, and the undescribed 'Bisa Rat' described by Flannery as sister to the recently described genus Halmaheramys. We also present an exploratory foray into the wider topic of Rattus phylogenetics and propose that a reorganisation of the Rattus genus should require that it be a monophyletic group, include at least the type species R. norvegicus and R. rattus (plus their close allies); and exclude the Bandicota/Nesokia clade and other such specialised genera.


Assuntos
Ratos/genética , África , Animais , Teorema de Bayes , Evolução Biológica , Citocromos b , Humanos , Camundongos , Filogenia , Ratos/classificação , Análise de Sequência de DNA
4.
Virol Sin ; 32(3): 235-244, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28669005

RESUMO

Seoul virus (SEOV), which is predominantly carried by Rattus norvegicus, is one of the major causes of hemorrhagic fever with renal syndrome (HFRS) in China. Hubei province, located in the central south of China, has experienced some of the most severe epidemics of HFRS. To investigate the mitochondrial DNA (mtDNA)-based phylogenetics of wild rats in Hubei, and the relationship with SEOV infection, 664 wild rats were captured from five trapping sites in Hubei from 2000-2009 and 2014-2015. Using reverse-transcription (RT)-PCR, 41 (6.17%) rats were found to be positive for SEOV infection. The SEOV-positive percentage in Yichang was significantly lower than that in other areas. The mtDNA D-loop and cytochrome b (cyt-b) genes of 103 rats were sequenced. Among these animals, 37 were SEOV-positive. The reconstruction of the phylogenetic relationship (based on the complete D-loop and cyt-b sequences) allowed the rats to be categorized into two lineages, R. norvegicus and Rattus nitidus, with the former including the majority of the rats. For both the D-loop and cyt-b genes, 18 haplotypes were identified. The geographic distributions of the different haplotypes were significantly different. There were no significant differences in the SEOVpositive percentages between different haplotypes. There were three sub-lineages for the D-loop, and two for cyt-b. The SEOV-positive percentages for each of the sub-lineages did not significantly differ. This indicates that the SEOV-positive percentage is not related to the mtDNA D-loop or cyt-b haplotype or the sub-lineage of rats from Hubei.


Assuntos
DNA Mitocondrial/genética , Febre Hemorrágica com Síndrome Renal/veterinária , Filogeografia , Ratos/classificação , Ratos/virologia , Doenças dos Roedores/virologia , Vírus Seoul/isolamento & purificação , Animais , China , Citocromos b/genética , DNA Mitocondrial/química , Haplótipos , Febre Hemorrágica com Síndrome Renal/virologia , RNA Viral/genética , RNA Viral/isolamento & purificação , Ratos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vírus Seoul/genética , Análise de Sequência de DNA
5.
Braz. J. Pharm. Sci. (Online) ; 53(1): e16136, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839443

RESUMO

Abstract Curcuma longa, which contains curcumin as a major constituent, has been shown many pharmacological effects, but it is limited using in clinical due to low bioavailability. In this study, we developed a phytosome curcumin formulation and evaluated the hepatoprotective effect of phytosome curcumin on paracetamol induced liver damage in mice. Phytosome curcumin (equivalent to curcumin 100 and 200 mg/kg body weight) and curcumin (200 mg/kg body weight) were given by gastrically and toxicity was induced by paracetamol (500 mg/kg) during 7 days. On the final day animals were sacrificed and liver function markers (ALT, AST), hepatic antioxidants (SOD, CAT and GPx) and lipid peroxidation in liver homogenate were estimated. Our data showed that phytosome has stronger hepatoprotective effect compared to curcumin-free. Administration of phytosome curcumin effectively suppressed paracetamol-induced liver injury evidenced by a reduction of lipid peroxidation level, and elevated enzymatic antioxidant activities of superoxide dismutase, catalase, glutathione peroxidase in mice liver tissue. Our study suggests that phytosome curcumin has strong antioxidant activity and potential hepatoprotective effects.


Assuntos
Animais , Masculino , Feminino , Ratos , Ratos/classificação , Curcumina/farmacologia , Curcuma/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Medicamentos Hepatoprotetores , Acetaminofen/efeitos adversos
6.
Braz. J. Pharm. Sci. (Online) ; 53(1): e15079, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839445

RESUMO

ABSTRACT The present study was designed to evaluate the in vivo effect of Allium sativum (garlic) hydroalcoholic extract on wound healing in rats. For this purpose, 72 mature Wistar rats were divided into four groups (n=18/each) to receive no treatment, placebo, Cicalfate(r), or 2% Allium sativum (AS) extract, administered topically to the wound area, for 21 days. Following the experimental period, tissue samples were dissected out and underwent to histopathological analyses. Fibroblasts, fibrocytes, mast cells, intra-cytoplasmic carbohydrate ratio, neovascularization, collagen deposition, and re-epithelialization were analyzed in all groups. Animals in the treated groups showed significant enhancement in fibroblast, fibrocyte, and mast-cell distribution. Significantly higher neovascularization was observed on day 3 after wound induction in AS-treated animals versus those in the placebo, Cicalfate, and untreated groups (P<0.05). A dose-dependent, significantly higher intra-cytoplasmic carbohydrate storage was observed in treated animals. Our data show that AS promotes wound healing due to its preliminary impact on mast-cell distribution, which enhanced collagen synthesis and upregulated angiogenesis, and shortened the healing process by enhancing the intra-cytoplasmic carbohydrate ratio.


Assuntos
Animais , Ratos , Cicatrização , Extratos Vegetais/análise , Alho/metabolismo , Ratos/classificação , Ferimentos e Lesões/prevenção & controle , Indutores da Angiogênese/farmacologia
7.
Braz. J. Pharm. Sci. (Online) ; 53(1): e16059, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839457

RESUMO

ABSTRACT Recent studies have shown a role of intestinal microbiota in obesity. The consumption of antibiotics in the last 70 years has led to changes in intestinal microbiota, which has led to weight gain and body fat accumulation. To evaluate the possibility of weight gain induced by antibiotics and the possible protective effect of probiotics, we divided 45 animals (Rattus norvegicus) into groups and administered the following treatments over two weeks: tetracycline, tetracycline + Lactobacillus gasseri, and NaCl. The animals were weighed over the course of 8 weeks, and at the end of the treatment period, they were measured and subjected to bioelectrical impedance analysis. The results show that the group receiving tetracycline alone had a higher body mass index (p=0.030), a greater Lee index (p=0.008), and a lower body water percentage than the control group, indicating a greater accumulation of body fat. The group receiving the probiotics with tetracycline presented similar results to the control group, indicating a possible protective effect of body fat accumulation in the group receiving tetracycline alone. The results show that tetracycline increased the concentration of body fat, and the use of probiotics was associated with an ability to protect the animals from the pro-obesity effect.


Assuntos
Animais , Masculino , Ratos , Ratos/classificação , Tetraciclinas/análise , Lactobacillus gasseri/metabolismo , Microbioma Gastrointestinal/genética , Anti-Infecciosos/administração & dosagem , Obesidade/fisiopatologia
8.
G3 (Bethesda) ; 6(7): 1969-77, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-27172215

RESUMO

Whole-genome sequencing of wild-derived rat species can provide novel genomic resources, which may help decipher the genetics underlying complex phenotypes. As a notorious pest, reservoir of human pathogens, and colonizer, the Asian house rat, Rattus tanezumi, is successfully adapted to its habitat. However, little is known regarding genetic variation in this species. In this study, we identified over 41,000,000 single-nucleotide polymorphisms, plus insertions and deletions, through whole-genome sequencing and bioinformatics analyses. Moreover, we identified over 12,000 structural variants, including 143 chromosomal inversions. Further functional analyses revealed several fixed nonsense mutations associated with infection and immunity-related adaptations, and a number of fixed missense mutations that may be related to anticoagulant resistance. A genome-wide scan for loci under selection identified various genes related to neural activity. Our whole-genome sequencing data provide a genomic resource for future genetic studies of the Asian house rat species and have the potential to facilitate understanding of the molecular adaptations of rats to their ecological niches.


Assuntos
Adaptação Fisiológica/genética , Variação Genética , Genoma , Polimorfismo de Nucleotídeo Único , Ratos/genética , Animais , Animais Selvagens , Sequência de Bases , Inversão Cromossômica , Mapeamento Cromossômico , Códon sem Sentido , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutagênese Insercional , Filogenia , Ratos/classificação , Análise de Sequência de DNA , Deleção de Sequência
9.
Rev. bras. plantas med ; 18(1,supl.1): 264-272, 2016. tab, graf
Artigo em Português | LILACS | ID: lil-782975

RESUMO

RESUMO A preocupação com o tratamento do Diabetes mellitus (DM) leva a uma crescente busca por terapias alternativas, como o uso de plantas medicinais, entre as quais, destaca-se o uso de Handroanthus heptaphyllus (Mart.) Mattos (popular Ipê roxo). Neste estudo realizamos a investigação química da presença de compostos fenólicos em H. heptaphyllus e o efeito do tratamento com o extrato aquoso da casca desta planta em parâmetros bioquímicos e nos níveis de lipoperoxidação tecidual e plasmática em animais diabéticos. Metodologia: Ratos Wistar machos foram submetidos ao desenvolvimento do quadro de DM por meio da administração intraperitoneal (IP) de Aloxano monohidrato (150 mg/Kg IP). Após a confirmação de hiperglicemia (>200 mg dL-1), os animais foram distribuídos nos grupos Diabético (D; n=6) e Diabético Tratado (DT; n=6). O tratamento consistiu na administração diária do extrato aquoso da casca de H. heptaphyllus via oral (v.o.) (150mg/Kg v.o.) por quatro semanas. O extrato aquoso foi analisado qualitativamente por cromatografia de camada delgada. Resultados: A análise qualitativa do extrato aquoso da casca indicou a presença de compostos fenólicos da subclasse flavonoides. O tratamento com o extrato aquoso reduziu a glicemia de jejum a partir da 3ª semana de tratamento, melhorou a resposta glicêmica à sobrecarga de glicose, diminuiu os níveis de triglicerídeos e índice LDL (Triglicerídeos/HDL). Estes resultados sugerem o uso terapêutico do extrato aquoso das cascas de H. heptaphyllus no tratamento do DM.


ABSTRACT Alternative medicine for diabetes mellitus (DM) treatment represents a growing research area on the use of medicinal plants, of which Handroanthus heptaphyllus (mart.) Mattos (popularly known as purple ipe) is most prominent. In this study, we investigated the presence of phenolic compounds and the effects of treatment with aqueous extract of in H. heptaphyllus in biochemical profile in plasma and the levels of lipid peroxidation in tissues and plasma in diabetic animals. Male Wistar rats were induced to develop DM through intraperitoneal (IP) administration of alloxan monohydrate (150 mg/kg IP). Once hyperglycemia (>200 mg dL-1) was confirmed, the animals were divided into the Diabetic (D; n=6) and Treated Diabetic (TD; n=6) groups. The TD group received daily administration (150 mg/kg v.o.) of aqueous extract of H. heptaphyllus for four weeks. The aqueous extract was also analyzed qualitatively by layer chromatography. Qualitative analysis of the aqueous extract of the bark indicated the presence of phenolic compounds from the flavonoid subclass. The treatment with the aqueous extract reduced fasting blood glucose levels from the third week of treatment on, improved the glycemic response to the glucose tolerance test, and lowered the levels of triglycerides and the LDL index (triglycerides/HDL). These findings suggest therapeutic use of the aqueous extract of H. heptaphyllus bark in treating DM.


Assuntos
Ratos , Ratos/classificação , Tabebuia/química , Compostos Fenólicos/análise , Plantas Medicinais/classificação , Diabetes Mellitus/fisiopatologia
10.
São Paulo; s.n; s.n; dez. 2015. 166 p. tab, graf, ilus.
Tese em Português | LILACS | ID: biblio-834072

RESUMO

Bisfenol A (BPA) é um insumo largamente utilizado na produção de plástico policarbonato e amplamente difundido no meio ambiente, levando o ser humano à exposição crônica desde o período intrauterino. A literatura aponta a possibilidade de BPA aumentar o risco de diversos tipos de câncer, mas são necessários estudos que possibilitem o entendimento de mecanismos pelos quais isso pode ocorrer. Neste trabalho foram investigados os efeitos do BPA ou nitro-BPA em células HL-60, MCF-7 e tecidos de ratos. Células HL-60 foram expostas ao BPA ou nitro-BPA nas concentrações de 25, 100 e 250 µM (0,1 % DMSO v/v) por 2, 24 ou 48 horas na presença ou ausência de H2O2 (40 nmol/5 x 104 células). Células MCF-7 foram expostas da mesma forma, sem o uso de H2O2, mas na presença e ausência de agonista (PCB) de receptor Ah. Ratos Sprague-Dawley machos receberam BPA diariamente ao longo de 4 semanas (50 mg/kg de peso corpóreo) por gavagem, na vigência e ausência de diabetes, com subsequente coleta de urina, fígado, rins, medula óssea e sangue. Nos experimentos com as células, a viabilidade, ciclo celular, fragmentação do DNA e a produção intracelular de espécies reativas de oxigênio (ROs) foram avaliadas por citometria de fluxo, a atividade da cadeia respiratória mitocondrial pelo ensaio do XTT, e a atividade de MPO de células HL-60 por ensaio de fluorescência, bem como a produção de •NO. A metilação e hidroximetilação global do DNA e os adutos 8-oxodG, CEdG, 1,N6-εdA, 1,N2-εdG e BPA-Gua no DNA das células, tecidos, meio de cultura e urina foram analisados por HPLC-ESI-MS/MS. O hemograma e mielograma dos animais foram obtidos no Laboratório de Hematologia Experimental da FCF USP. Observou-se que tanto BPA quanto nitro-BPA induziram a geração de ROS em células HL-60 logo após 2h de incubação. BPA levou subsequentemente à perda de atividade da cadeia respiratória mitocondrial, aumento da permeabilidade da membrana plasmática, fragmentação do DNA, parada na fase G2/M do ciclo celular e hipermetilação acompanhada de hipohidroximetilação global do DNA. A citotoxicidade induzida pelas mesmas concentrações de nitro-BPA em células HL-60 foi menos pronunciada, sem perda de atividade da cadeia respiratória mitocondrial, com pouca fragmentação do DNA, mas com parada na fase G0/G1 do ciclo celular e indução de hipohidroximetilação global do DNA na presença de H2O2. Não foi observada a indução de adutos de DNA nas células HL-60 incubadas com BPA, mas sim de CEdG nas células incubadas com nitro-BPA. Os dados obtidos a partir da exposição das células HL-60 a BPA e nitro-BPA nos indicam que as duas moléculas provocam alterações metabólicas distintas nesse tipo celular, independentes da via estrogênica, que levam a alterações predominantemente epigenéticas (BPA) ou genéticas e epigenéticas (nitro-BPA), que podem ter consequências fenotípicas, como progressão maligna, que precisam ser investigadas. Foi observado que as células MCF-7 são mais resistentes que as células HL-60 à citotoxicidade induzida por BPA e nitro-BPA. Como resultado da exposição das células MCF-7 a BPA, houve pequeno aumento da permeabilidade da membrana plasmática (250 µM), indução dos níveis de ROS após 24 h (25 µM) e aumento da população de células em sub G1, ou seja, com DNA fragmentado (100 µM e 250 µM), mas sem alteração do ciclo celular. No caso de nitro-BPA, foi observada parada do ciclo celular em G2/M (25 µM, 100 µM e 250 µM), assim como aumento de permeabilidade da membrana plasmática após 24 h de incubação (25 µM, 250 µM), sem indução de ROS ou aumento de células em sub G1. Entretanto, observou-se aumento dos níveis de CEdG e 8-oxodG no DNA das células incubadas com BPA (100 µM, 250 µM) sem a ativação prévia de receptores Ah. A ativação dos receptores Ah com PCB levou a menor aumento do nível das lesões após as incubações com BPA. A maior resistência das células MCF-7 aos efeitos citotóxicos do BPA está provavelmente relacionada à ação estrogênica desse xenobiótico. A sinalização estrogênica juntamente com o aumento dos níveis de lesões no DNA aumenta a chance de mutações e de transformação maligna. Nas células com ativação do receptor Ah, BPA levou ainda ao aumento da hidroximetilação global, sem alteração da metilação global do DNA. Os animais não diabéticos expostos ao BPA apresentaram quantidades diminuídas de promielócitos, blastos e bastonetes na medula óssea (aplasia medular), sem alteração no hemograma. Houve aumento dos níveis de CEdG no fígado, da metilação e hidroximetilação global do DNA hepático, e não foi observada alteração das marcas epigenéticas e adutos de DNA no rim ou na urina. Os animais diabéticos expostos ao BPA apresentaram aumento do número de eosinófilos e linfócitos na medula óssea, podendo-se sugerir a indução de um estado inflamatório alérgico, e aumento do número total de hemácias circulantes e do hematócrito. Houve aumento dos níveis de CEdG, da metilação e hidroximetilação global do DNA hepático, aumento dos níveis de 8-oxodG no DNA renal, sem alteração das marcas epigenéticas no rim, e não foi observada alteração dos adutos de DNA na urina. Os dados obtidos apontam para a geração de ROS como uma importante via de cito- e genotoxicidade induzidas por BPA. Sua biotransformação para BPA-3,4- quinona nos modelos utilizados parece ter menor importância para os efeitos, uma vez que não foi detectada a lesão BPA-Gua em nenhuma amostra de DNA, meio de cultura das células ou urina dos animais. Alterações metabólicas induzidas por BPA e ROS podem favorecer as alterações das marcas epigenéticas observadas no DNA das células HL-60, MCF-7 e fígado dos animais. Todas essas alterações podem contribuir para a transformação maligna de células expostas ao BPA


Bisphenol A (BPA) is a compound widely used in polycarbonate plastic production and widespread in the environment, humans are chronic exposed to BPA in intrauterine period and entire life. The literature suggests the possibility of BPA increase the risk of developing cancers, but studies are required to enable the understanding of mechanisms by which this can occur. HL -60 cells were exposed to BPA or nitro-BPA at concentrations of 25, 100 and 250 uM (0.1% DMSO v/v) for 2, 24 or 48 hours in presence or absence of H2O2 (40 nmol/5x104 cells), MCF-7 cells followed a similar profile of exposure without the use of H2O2, but in presence or absence of Ah agonist receptor (PCB126). Male Sprague-Dawley rats received BPA daily over 4 weeks (50 mg/kg body weight) by gavage in presence and absence of diabetes, with subsequent collection of urine, liver, kidney, bone marrow and circulating blood. The viability, cell cycle, DNA fragmentation and the intracellular production of reactive oxygen species (ROS) was evaluated by flow cytometry, MPO activity and NO production was evaluated by fluorescence assay for HL- 60 cells, mitochondrial activity by XTT assay, and the global DNA methylation was checked by HPLC-PDA. DNA adducts 8-oxodG, CEdG, 1,N6-εdA, 1,N6-εdG and BPA-Gua were quantified by HPLC- ESI-MS/MS in DNA of cells, culture medium, urine and tissue collected from Sprague-Dawley rats. Blood count and bone marrow examination were obtained in collaboration with Experimental Hematology Laboratory of University of Sao Paulo We observed that both BPA and BPANO2 induced ROS generation in HL- 60 cells after 2 hours of incubation. BPA subsequently led to failure of mitochondrial respiratory chain activity, increased permeability of the plasma membrane, DNA fragmentation, arrest in G2/M phase of cell cycle, DNA hypermethylation with global hipohydroxymethylation. We saw low cytotoxicity in HL-60 cells induced by nitro-bpa n the same concentration, without loss of mitochondrial respiratory chain activity, discrete DNA fragmentation, but leading cell cycle to stopping at G0/G1 phase, and induction of DNA global hypermethylation. No lesions were observed in the DNA of HL-60 cells.The results obtained from the exposure of HL-60 cells to BPA and nitro-BPA indicate that these two molecules induce different metabolic abnormalities in this cell line, independent of estrogen pathway, leading to changes in epigenetic (BPA) or genetic and epigenetic (nitro-BPA) profile, that can induce phenotypic consequences such as malignant progression. It was observed along the study that MCF-7 cells are more resistant than HL-60 cells to cell damage induced by BPA and nitro-BPA. As a result of MCF-7 cells exposure to BPA, we saw a slight increase in membrane permeability (250 mM), ROS generation after 24h (25 mM) and increase in cell population in sub G1, so we had DNA fragmentation (100 uM and 250 uM), but with no effect on cell cycle. However, we observed increased levels of CEdG and 8-oxodG on DNA of cells incubated with BPA (100 uM, 250 mM) without prior activation of Ah receptors. The activation of Ah receptors with PCB took a small increase in the level of DNA lesions after incubations with BPA. MCF-7 cells resistance to the cytotoxic effects of BPA is probably related to estrogen action of this compound. Estrogen signaling in addition with the increased levels of DNA damage increases the chance of mutations and malignant transformation. In cells with Ah receptor activation, BPA also led to increased DNA global hydroxymethylation, without changing the global DNA methylation. Nondiabetic animals exposed to BPA had decreased amounts of promyelocytes, blasts and rods in the bone marrow, with any change in blood count. There were an increase of CEdG levels in liver, methylation and global hydroxymethylation on hepatic DNA, and was observed any alteration on epigenetic markers and DNA adducts in kidney or urine. On the other hand diabetic animals exposed to BPA showed increased numbers of eosinophils and lymphocytes in bone marrow, suggesting the induction of an allergic inflammatory state. There were increased levels of CEdG, methylation and global hydroxymethylation on hepatic DNA, increased 8-oxodG levels on kidney DNA without changing epigenetic markers, was not observed DNA adducts in urine. The data obtained indicate that the generation of ROS could be the major route of cytotoxic and genotoxic induced by BPA exposure. BPA biotransformation to BPA-3,4-quinone used in the models seem to have poor effects, since we was not detected BPA-Gua lesion in any DNA sample, culture medium of cells or urine of the animals. Metabolic changes induced by BPA and ROS can enable changes in epigenetic markers observed in the DNA of HL-60 cells, MCF-7 and liver tissue. All these changes may contribute to malignant transformation of cells that were exposed to BPA


Assuntos
Animais , Ratos , Ratos/classificação , Bis-Fenol A-Glicidil Metacrilato , Células HL-60/citologia , Epigênese Genética , Células MCF-7/citologia , Bifenilos Policlorados/agonistas , Diabetes Mellitus
11.
J Am Assoc Lab Anim Sci ; 54(5): 497-506, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26424247

RESUMO

The 2011 Guide for the Care and Use of Laboratory Animals contains recommendations regarding the amount of cage space for mothers with litters. Literature on cage-space use in breeding rats is sparse. We hypothesized that, if present, differences in behavior and reproduction would be detected between the smallest and largest cages tested. BN/Crl and Crl:CD(SD) rats were assigned to a cage treatment (580 cm(2), 758 cm(2), 903 cm(2), or 1355 cm(2)) and breeding configuration (single: male removed after birth of pups; pair: 1 male, 1 female) in a factorial design for 12 wk. All cages received 20 to 25 g of nesting material, and nests were scored weekly. Pups were weaned, sexed, and weighed between postnatal days 18 and 26. Adult behavior and location in the cage were videorecorded by scan-sampling on the litter's postnatal days 0 through 8 and 14 through 21. Press posture in adults and play behavior in pups were recorded according to a 1-0 sampling method. Differences in reproductive parameters were limited to expected differences related to rat genetic background and weaning weight in pups, which was lowest in the pair-bred CD rats in the smallest cages. Press posture in adults in the smaller cages increased as the pups became mobile. Pair-housed outbred rats in the smallest commercially available cage we tested showed behavioral changes and a lower pup weaning weight. Both laboratory animal scientists and caging manufacturers should address the challenge of providing more biologically relevant cage complexity rather than merely increasing floor space.


Assuntos
Animais de Laboratório , Comportamento Animal , Abrigo para Animais , Comportamento Materno , Ratos/fisiologia , Animais , Peso Corporal , Feminino , Masculino , Ratos/classificação , Ratos/genética , Ratos Endogâmicos BN , Reprodução , Especificidade da Espécie , Desmame
12.
Acta cir. bras ; 30(2): 108-114, 02/2015.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1456226

RESUMO

PURPOSE: To evaluate the effects of preconditioning with oils mixes containing ω3/ω6/ω9 associated with micro-currents on skin repair in rats. METHODS: One-hundred and eight Wistar rats randomized into G-1, G-2 and G-3 groups were treated with saline (0.9%), mix 1 (corn+soybean oils) and mix 2 (olive+canola+flaxseed oils), respectively, in a single dose (0.01ml/g) by gavage. Next, each group was subdivided into sham and stimulated subgroups. Pulsed-wave microcurrents (0.5 µA, 0.5 Hz) were applied to stimulated subgroups for 20 min. One hour later anesthetized rats were subjected to surgery. A dorsal incision (6 cm long) was carried out and closed with interrupted nylon sutures. Samples (1cm2 ) were harvested from the mid-portion of the incision on the 7, 14, 21 post-operative (P.O.) days. Variables were analyzed using Mann-Whitney/Dunn tests Significance level was set to 5 % (p<0.05). RESULTS: Micro-currents promoted increase of exudate and reduction of epithelialization on day 7 in G1 rats. Mixes 1/2 reduced vascularization on 7/14th days P.O. Both 1/2 mixes reduced fibrosis on day 14. Preconditioning with mix 1 led to increased expression of NF-kB on the 7th day. CONCLUSION: Preconditioning with microcurrents has pro-inflammatory effects while oil mixes 1 and 2 decrease fibrosis and vascularization in the proliferative phase of cicatrization.


Assuntos
Animais , Cicatrização/fisiologia , Eletrochoque , Pele , Ácidos Graxos/análise , Ratos/classificação
13.
Vector Borne Zoonotic Dis ; 15(1): 3-12, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25629775

RESUMO

From the perspective of ecology of zoonotic pathogens, the role of the Old World rats of the genus Rattus is exceptional. The review analyzes specific characteristics of rats that contribute to their important role in hosting pathogens, such as host-pathogen relations and rates of rat-borne infections, taxonomy, ecology, and essential factors. Specifically the review addresses recent taxonomic revisions within the genus Rattus that resulted from applications of new genetic tools in understanding relationships between the Old World rats and the infectious agents that they carry. Among the numerous species within the genus Rattus, only three species-the Norway rat (R. norvegicus), the black or roof rat (R. rattus), and the Asian black rat (R. tanezumi)-have colonized urban ecosystems globally for a historically long period of time. The fourth invasive species, R. exulans, is limited to tropical Asia-Pacific areas. One of the points highlighted in this review is the necessity to discriminate the roles played by rats as pathogen reservoirs within the land of their original diversification and in regions where only one or few rat species were introduced during the recent human history.


Assuntos
Vetores de Doenças , Espécies Introduzidas , Ratos/classificação , Distribuição Animal , Animais , Doenças Transmissíveis , Ecossistema , Interações Hospedeiro-Patógeno , Humanos , Doenças dos Roedores/microbiologia , Doenças dos Roedores/parasitologia , Doenças dos Roedores/virologia , Zoonoses
14.
Braz. j. pharm. sci ; 51(3): 637-642, July-Sept. 2015. graf
Artigo em Inglês | LILACS | ID: lil-766326

RESUMO

The aim of the present study was to investigate the protective effect of crocin on gastric mucosal lesions caused by ischemia-reperfusion (I/R) injury in rats. Thirty-two male rats were randomly divided into sham, I/R, I/R + crocin pretreatment and crocin alone groups. To induce I/R lesions, the celiac artery was clamped for 30 min, and the clamp was then removed to allow reperfusion for 3 h. Crocin-pretreated rats received crocin (15 mg/kg, i.p.) 30 min prior to the induction of I/R injury. Samples of gastric mucosa were collected to quantify the protein expression of caspase-3, an apoptotic factor, and inducible nitric oxide synthase (iNOS), a pro-inflammatory protein, by Western blot. Pretreatment with crocin decreased the total area of gastric lesions and decreased the protein expression levels of caspase-3 and iNOS induced by I/R injury. Our findings showed a protective effect of crocin in gastric mucosa against I/R injury. This effect of crocin was mainly mediated by reducing the protein expression of iNOS and caspase-3.


O objetivo do presente estudo foi investigar o efeito protetor da crocina em lesões da mucosa gástrica causadas por isquemia-reperfusão (I/R) em ratos. Trinta e dois ratos machos aleatoriamente divididos em grupos de ratos normais, operados como controle, I/R. I/R + pré-tratamento com crocina e crocina sozinha. Para induzir lesões I/R, a artéria celíaca foi grampeada durante 30 minutos e, em seguida, o grampo foi removido para permitir a reperfusão por 3 h. Ratos com pré-tratamento com crocina receberam crocina (15 mg/kg, ip) 30 minutos antes da indução do dano I/R. Amostras de mucosa gástrica foram coletadas para qiuantificar a expressão da proteína da caspase-3, o fator apoptótico, e óxido nítrico sintase induzível (iNOS), uma proteína anti-inflamatória, pela técnica de Western Blot. O pré-tratamento com crocina diminuiu a área total de lesões gástricas e a expressão de níveis de caspase-3 e iNOS induzidas pelo dano I/R. Nossos resultados mostraram o efeito protetor da crocina na mucosa gástrica contra o dano I/R. Este efeito foi mediado, principalmente, por diminuição da expressão das proteínas iNOS e caspase-3.


Assuntos
Ratos , Ratos/classificação , Traumatismo por Reperfusão , Anti-Inflamatórios/efeitos adversos , Carotenoides/análise , Caspase 3/análise , Gastrite/prevenção & controle
15.
Rev. bras. plantas med ; 17(4,supl.2): 875-880, 2015. graf
Artigo em Português | LILACS | ID: lil-771157

RESUMO

RESUMO O objetivo deste estudo foi analisar o efeito do óleo de pequi no processo cicatricial de lesões cutâneas em ratos. A pesquisa foi iniciada após a provação da CEUA- FACID sob o nº de protocolo 005/12 e obedeceu aos princípios éticos da experimentação animal de acordo com a Lei Federal nº 11.794/2008. Foram utilizados 20 ratos machos, Wistar (Rattusnorvegicus), peso corpóreo de 300-350g, divididos aleatoriamente em dois grupos iguais: GI- controle (C); GII- tratado com óleo de pequi (T). Cada grupo foi dividido em dois subgrupos, de cinco animais cada, conforme os tempos experimentais estudados de 7(A) e 14(B) dias. Após anestesia e antissepsia foi produzida cirurgicamente ferida circular de 2,5 cm de diâmetro na região dorso lombar do animal. Os animais do Grupo II foram tratados com aplicação tópica diária de 1 ml do óleo de pequi, respeitando os tempos experimentais descritos. Concomitante à mensuração da área da lesão, os ratos foram eutanasiados para realização do processamento histológico e análise do percentual de regressão das lesões. No grupo GII nos diferentes tempos experimentais de 7 e 14 dias foi observado maior percentual de regressão das lesões em relação ao GI (p < 0,05). A partir da análise histológica foi possível detectar que no GII houve menor número de células inflamatórias e maior número de fibroblastos em relação ao GI nos diferentes tempos experimentais (p < 0,001). Conclui-se que o uso do óleo de pequi apresentou influência positiva no processo de reparo de lesões cutâneas em ratos, por promover maior velocidade do reparo tecidual, fato evidenciado pelo fechamento mais rápido das feridas e observação de características inflamatórias reduzidas no grupo tratado em relação ao grupo controle, sugerindo que a inflamação pode já ter regredido no grupo tratado.


ABSTRACT The aim of this study was to analyze the effect of pequi oil in the healing process of skin lesions in rats. The research was initiated after the ordeal of CEUA- FACID with protocol No. 005/12 and following the ethical principles of animal experimentation according to the Federal Law No. 11,794 / 2008. 20 Wistar rats were used (Rattus norvegicus), with body weight ranging from 300-350g. They were randomly divided into two groups: GI control (C) and GII treated with pequi oil (T). Each group was divided into two subgroups of five animals each, according to the experimental study of 7 days (A) and 14 (B) days. After anesthesia and antisepsis, a circular wound of 2.5 cm of diameter was surgically inflicted in the lumbar dorsal region of the animal. The animals in Group II were treated with daily topical application of 1 ml of pequi oil, respecting the described experimental times. Concomitantly with the measurement of the injury area, the rats were euthanized so that a histological processing and a regression analysis of the percentage of injuries could be performed. In GII, at different experimental times of 7 and 14 days, there were a higher percentage of lesions regression compared to GI (p <0.05). From the histological examination it was possible to detect that, at GII, there were a lower number of inflammatory cells and increased number of fibroblasts compared to IM at different time of the trial (P <0.001). It is concluded that the use of pequi oil presented positive influence on the healing process of skin lesions in rats by promoting quicker tissue repair, as indicated by the faster closure of the wounds and the observation of reduced inflammatory characteristics in the group treated compared to the control group, suggesting that the inflammation could have already receded in the treated group.


Assuntos
Masculino , Ratos , Ratos/classificação , Cicatrização , Óleos Voláteis/análise , Ericales/classificação , Desenluvamentos Cutâneos/classificação , Ferimentos e Lesões/diagnóstico , Inflamação/diagnóstico
16.
Ecology ; 95(8): 2268-76, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25230477

RESUMO

Multiple invasive species have now established at most locations around the world, and the rate of new species invasions and records of new invasive species continue to grow. Multiple invasive species interact in complex and unpredictable ways, altering their invasion success and impacts on biodiversity. Incumbent invasive species can be replaced by functionally similar invading species through competitive processes; however the generalized circumstances leading to such competitive displacement have not been well investigated. The likelihood of competitive displacement is a function of the incumbent advantage of the resident invasive species and the propagule pressure of the colonizing invasive species. We modeled interactions between populations of two functionally similar invasive species and indicated the circumstances under which dominance can be through propagule pressure and incumbent advantage. Under certain circumstances, a normally subordinate species can be incumbent and reject a colonizing dominant species, or successfully colonize in competition with a dominant species during simultaneous invasion. Our theoretical results are supported by empirical studies of the invasion of islands by three invasive Rattus species. Competitive displacement is prominent in invasive rats and explains the replacement of R. exulans on islands subsequently invaded by European populations of R. rattus and R. norvegicus. These competition outcomes between invasive species can be found in a broad range of taxa and biomes, and are likely to become more common. Conservation management must consider that removing an incumbent invasive species may facilitate invasion by another invasive species. Under very restricted circumstances of dominant competitive ability but lesser impact, competitive displacement may provide a novel method of biological control.


Assuntos
Aves/fisiologia , Ecossistema , Espécies Introduzidas , Modelos Biológicos , Ratos/fisiologia , Animais , Monitoramento Ambiental , Ratos/classificação , Especificidade da Espécie
17.
PLoS One ; 9(5): e98002, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24865350

RESUMO

The genus Rattus is highly speciose, the taxonomy is complex, and individuals are often difficult to identify to the species level. Previous studies have demonstrated the usefulness of phylogenetic approaches to identification in Rattus but some species, especially among the endemics of the New Guinean region, showed poor resolution. Possible reasons for this are simple misidentification, incomplete gene lineage sorting, hybridization, and phylogenetically distinct lineages that are unrecognised taxonomically. To assess these explanations we analysed 217 samples, representing nominally 25 Rattus species, collected in New Guinea, Asia, Australia and the Pacific. To reduce misidentification problems we sequenced museum specimens from earlier morphological studies and recently collected tissues from samples with associated voucher specimens. We also reassessed vouchers from previously sequenced specimens. We inferred combined and separate phylogenies from two mitochondrial DNA regions comprising 550 base pair D-loop sequences and both long (655 base pair) and short (150 base pair) cytochrome oxidase I sequences. Our phylogenetic species identification for 17 species was consistent with morphological designations and current taxonomy thus reinforcing the usefulness of this approach. We reduced misidentifications and consequently the number of polyphyletic species in our phylogenies but the New Guinean Rattus clades still exhibited considerable complexity. Only three of our eight New Guinean species were monophyletic. We found good evidence for either incomplete mitochondrial lineage sorting or hybridization between species within two pairs, R. leucopus/R. cf. verecundus and R. steini/R. praetor. Additionally, our results showed that R. praetor, R. niobe and R. verecundus each likely encompass more than one species. Our study clearly points to the need for a revised taxonomy of the rats of New Guinea, based on broader sampling and informed by both morphology and phylogenetics. The remaining taxonomic complexity highlights the recent and rapid radiation of Rattus in the Australo-Papuan region.


Assuntos
DNA Mitocondrial/genética , Evolução Molecular , Mitocôndrias/genética , Filogenia , Ratos/anatomia & histologia , Ratos/genética , Animais , Mitocôndrias/efeitos da radiação , Nova Guiné , Reação em Cadeia da Polimerase , Radiação , Ratos/classificação , Análise de Sequência de DNA
18.
Acta cir. bras ; 29(4): 252-260, abr. 2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-706953

RESUMO

To construct a new biomaterial-small intestinal submucosa coated with gelatin hydrogel incorporating basic fibroblast growth factor, and to evaluate the new biomaterials for the reconstruction of abdominal wall defects. Thirty six Sprague-Dawley rats were used in the animal experiments and randomly divided into three groups. The new biomaterial was constructed by combining small intestinal submucosa with gelatin hydrogel for basic fibroblast growth factor release. Abdominal wall defects were created in rats, and repaired using the new biomaterials (group B), compared with small intestinal submucosa (group S) and ULTRAPROTM mesh (group P). Six rats in each group were sacrificed at three and eight weeks postoperatively to examine the gross effects, inflammatory responses, collagen deposition and neovascularization. After implantation, mild adhesion was caused in groups B and S. Group B promoted more neovascularization than group S at three weeks after implantation, and induced significantly more amount of collagen deposition and better collagen organization than groups S and P at eight weeks after implantation. Small intestinal submucosa coated with gelatin hydrogel incorporating basic fibroblast growth factor could promote better regeneration and remodeling of host tissues for the reconstruction of abdominal wall defects.


Assuntos
Animais , Ratos , Fibroblastos , Hidrogéis , Mucosa Intestinal/anatomia & histologia , Parede Abdominal/anatomia & histologia , Ratos/classificação
19.
Acta cir. bras ; 29(4): 274-279, abr. 2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-706955

RESUMO

To evaluate the effect of diabetes mellitus and of sildenafil citrate on female urethral function. Twenty nine female rats were divided into four groups: G1 - (n=9), normal rats; G2 - (n=6), normal rats treated with sildenafil citrate; G3 - (n=9) rats with alloxan-induced diabetes; G4 - (n=5) rats with alloxan-induced diabetes treated with sildenafil citrate. Under anesthesia, urodynamic evaluation was performed by cystometry and urethral pressure simultaneously. A significant increase in urethral pressure was observed during micturition. Sildenafil citrate can partially reduced urethral pressure in diabetic female rats.


Assuntos
Animais , Ratos , Alloxanum , Complicações do Diabetes/patologia , Bexiga Urinária , Uretra/anatomia & histologia , Ratos/classificação
20.
Acta cir. bras ; 29(4): 268-273, abr. 2014. graf
Artigo em Inglês | LILACS | ID: lil-706956

RESUMO

To investigate the neuroprotective effects of Sulindac on the hippocampal complex after global cerebral ischemia/reperfusion (I/R) injury in rats. Thirty one Sprague-Dawley rats were used, distributed into group I (sham) n:7 were used as control. For group II (n:8), III (n:8) and IV (n:8) rats, cerebral ischemia was performed via the occlusion of bilateral internal carotid artery for 45 minutes and continued with reperfusion process. 0.3 mL/kg/h 0.9 % sodium chloride was infused intraperitoneally to the Group II rats before ischemia, 5μg/kg/h/0.3 ml sulindac was infused intraperitoneally to the Group III rats before ischemia and 5μg/kg/h/0.3 ml sulindac was infused intraperitoneally to the Group IV rats after ischemia and before reperfusion process. The levels of MDA, GSH and MPO activity were measured in the left hippocampus tissue. The hippocampal tissue of all group members were taken for histopathological study. The MDA and MPO levels increased from group I (control) to group II (I/R) (P<0.05) and decreased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05). Beside these, the GSH levels decreased from group I (control) to group II (I/R) (P<0.05) and increased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05).The number of apoptotic neurons increased from group I (control) to group II (I/R) (P<0.05) and decreased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05). The Sulindac may have neuroprotective effects on ischemic neural tissue to prevent the reperfusion injury after ischemia.


Assuntos
Animais , Ratos , Fármacos Neuroprotetores/análise , Isquemia/patologia , Reperfusão , Ferimentos e Lesões , Ratos/classificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...