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1.
Braz. j. biol ; 84: e256933, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364505

RESUMO

Anticarsia gemmatalis Hünber, 1818 is one of the main defoliating species in the soybean crop. Bacillus thuringiensis Berliner, 1915, is a bacterium used in the biological control of this pest species. Resistant populations and their sublethal effects caused by the use of the bacteria have already been reported; however, there are no studies on phenotypic plasticity in adulthood exposed to Bt-based bioinsecticide sub-doses. This study aimed to evaluate the morphometry of A. gemmatalis adults under laboratory conditions submitted to the Bt-based bioinsecticide Dipel® over the three generations. The body segments mensuread were width, length, and area of the anterior and posterior wings, the weight of the integument, chest, abdomen, wings, and the whole adult of males and females. Among the treatments, LC5 in the first generation and LC10 in the second generation were those with lower thresholds in relation to the weight of the chest and abdomen, considering the proportions of the body smaller than the females. The female's weight adulthood was reduced by 10% about males, and, only in the first generation. Males have larger body size and more pronounced phenotypic plasticity than females. Here, we demonstrate the first study assessing the phenotypic plasticity of A. gemmatalis adults.


Anticarsia gemmatalis Hünber, 1818 é uma das principais espécies desfolhadoras da cultura da soja. Bacillus thuringiensis Berliner, 1915, é uma bactéria utilizada no controle biológico dessa espécie de praga. Populações resistentes e seus efeitos subletais causados pelo uso da bactéria já foram relatados, no entanto, não há estudos sobre a plasticidade fenotípica na idade adulta exposta a subdoses de bioinseticida à base de Bt. Este trabalho teve como objetivo avaliar a morfometria de adultos de A. gemmatalis em condições de laboratório submetidos ao bioinseticida Dipel® ao longo de três gerações. Os segmentos corporais mensuráveis eram largura, comprimento e área das asas anterior e posterior, o peso do tegumento, tórax, abdômen, asas e todo o adulto de machos e fêmeas. Dentre os tratamentos, CL5 na primeira geração e CL10 na segunda geração foram aqueles com limiares mais baixos em relação ao peso do tórax e abdômen, considerando as proporções do corpo menores que as do sexo feminino. O peso da fêmea na idade adulta foi reduzido em 10% em relação aos machos e, apenas na primeira geração. Os machos têm tamanho corporal maior e plasticidade fenotípica mais pronunciada do que as fêmeas. Este estudo demonstra o primeiro estudo avaliando a plasticidade fenotípica de adultos de A. gemmatalis.


Assuntos
Animais , Fenótipo , Glycine max , Bacillus thuringiensis , Controle Biológico de Vetores
2.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469404

RESUMO

Abstract Anticarsia gemmatalis Hünber, 1818 is one of the main defoliating species in the soybean crop. Bacillus thuringiensis Berliner, 1915, is a bacterium used in the biological control of this pest species. Resistant populations and their sublethal effects caused by the use of the bacteria have already been reported; however, there are no studies on phenotypic plasticity in adulthood exposed to Bt-based bioinsecticide sub-doses. This study aimed to evaluate the morphometry of A. gemmatalis adults under laboratory conditions submitted to the Bt-based bioinsecticide Dipel® over the three generations. The body segments mensuread were width, length, and area of the anterior and posterior wings, the weight of the integument, chest, abdomen, wings, and the whole adult of males and females. Among the treatments, LC5 in the first generation and LC10 in the second generation were those with lower thresholds in relation to the weight of the chest and abdomen, considering the proportions of the body smaller than the females. The females weight adulthood was reduced by 10% about males, and, only in the first generation. Males have larger body size and more pronounced phenotypic plasticity than females. Here, we demonstrate the first study assessing the phenotypic plasticity of A. gemmatalis adults.


Resumo Anticarsia gemmatalis Hünber, 1818 é uma das principais espécies desfolhadoras da cultura da soja. Bacillus thuringiensis Berliner, 1915, é uma bactéria utilizada no controle biológico dessa espécie de praga. Populações resistentes e seus efeitos subletais causados pelo uso da bactéria já foram relatados, no entanto, não há estudos sobre a plasticidade fenotípica na idade adulta exposta a subdoses de bioinseticida à base de Bt. Este trabalho teve como objetivo avaliar a morfometria de adultos de A. gemmatalis em condições de laboratório submetidos ao bioinseticida Dipel® ao longo de três gerações. Os segmentos corporais mensuráveis eram largura, comprimento e área das asas anterior e posterior, o peso do tegumento, tórax, abdômen, asas e todo o adulto de machos e fêmeas. Dentre os tratamentos, CL5 na primeira geração e CL10 na segunda geração foram aqueles com limiares mais baixos em relação ao peso do tórax e abdômen, considerando as proporções do corpo menores que as do sexo feminino. O peso da fêmea na idade adulta foi reduzido em 10% em relação aos machos e, apenas na primeira geração. Os machos têm tamanho corporal maior e plasticidade fenotípica mais pronunciada do que as fêmeas. Este estudo demonstra o primeiro estudo avaliando a plasticidade fenotípica de adultos de A. gemmatalis.

3.
Sci Rep ; 13(1): 7147, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37130900

RESUMO

Developing new capabilities to predict the risk of intracranial aneurysm rupture and to improve treatment outcomes in the follow-up of endovascular repair is of tremendous medical and societal interest, both to support decision-making and assessment of treatment options by medical doctors, and to improve the life quality and expectancy of patients. This study aims at identifying and characterizing novel flow-deviator stent devices through a high-fidelity computational framework that combines state-of-the-art numerical methods to accurately describe the mechanical exchanges between the blood flow, the aneurysm, and the flow-deviator and deep reinforcement learning algorithms to identify a new stent concepts enabling patient-specific treatment via accurate adjustment of the functional parameters in the implanted state.


Assuntos
Aneurisma Roto , Procedimentos Endovasculares , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/cirurgia , Stents , Resultado do Tratamento , Hemodinâmica , Procedimentos Endovasculares/métodos
4.
Braz J Biol ; 84: e256933, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35293546

RESUMO

Anticarsia gemmatalis Hünber, 1818 is one of the main defoliating species in the soybean crop. Bacillus thuringiensis Berliner, 1915, is a bacterium used in the biological control of this pest species. Resistant populations and their sublethal effects caused by the use of the bacteria have already been reported; however, there are no studies on phenotypic plasticity in adulthood exposed to Bt-based bioinsecticide sub-doses. This study aimed to evaluate the morphometry of A. gemmatalis adults under laboratory conditions submitted to the Bt-based bioinsecticide Dipel® over the three generations. The body segments mensuread were width, length, and area of the anterior and posterior wings, the weight of the integument, chest, abdomen, wings, and the whole adult of males and females. Among the treatments, LC5 in the first generation and LC10 in the second generation were those with lower thresholds in relation to the weight of the chest and abdomen, considering the proportions of the body smaller than the females. The female's weight adulthood was reduced by 10% about males, and, only in the first generation. Males have larger body size and more pronounced phenotypic plasticity than females. Here, we demonstrate the first study assessing the phenotypic plasticity of A. gemmatalis adults.


Assuntos
Bacillus thuringiensis , Mariposas , Adaptação Fisiológica , Animais , Feminino , Proteínas Hemolisinas/farmacologia , Masculino , Glycine max
6.
Int J Endocrinol ; 2019: 4518742, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467527

RESUMO

BACKGROUND: The incidence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) has been increasing in the last five decades, but there is no large-scale data regarding these tumours in Portugal. We conducted a cross-sectional, multicentric study in main Portuguese centers to evaluate the clinical, pathological, and therapeutic profile of GEP-NENs. METHODS: From November, 2012, to July, 2014, data from 293 patients diagnosed with GEP-NENs from 15 centers in Portugal was collected and registered in an online electronic platform. RESULTS: Median age at diagnosis was 56.5 (range: 15-87) years with a preponderance of females (54.6%). The most frequent primary sites were the pancreas (31.1%), jejunum-ileum (24.2%), stomach (13.7%), and rectum (8.5%). Data regarding hormonal status was not available in most patients (82.3%). Stratified by the tumour grade (WHO 2010 classification), we observed 64.0% of NET G1, 24.7% of NET G2, and 11.3% of NEC. Poorly differentiated tumours occurred mainly in older patients (p = 0.017), were larger (p < 0.001), and presented more vascular (p = 0.004) and lymphatic (p = 0.001) invasion. At the time of diagnosis, 44.4% of GEP-NENs presented metastatic disease. Surgery (79.6%) and somatostatin analogues (30.7%) were the most frequently used therapies of GEP-NENs with reported grading. CONCLUSION: In general, Portuguese patients with GEP-NENs presented similar characteristics to other populations described in the literature. This cross-sectional study represents the first step to establish a national database of GEP-NENs that may aid in understanding the clinical and epidemiological features of these tumours in Portugal.

8.
Clin Microbiol Infect ; 25(1): 60-64, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29715552

RESUMO

BACKGROUND: The paucity of licensed monoclonal antibodies (mAbs) in the infectious diseases arena strongly contrasts with the ready availability of these therapeutics for use in other conditions. AIMS: This narrative review aims to assess the potential of monoclonal antibody-based interventions for infectious diseases. SOURCES: A review of the literature via the Medline database was performed and complemented by published official documents on licensed anti-infective mAbs. In addition, ongoing trials were identified through a search of the clinical trial registration platform ClinicalTrials.gov. CONTENT: We identified the few infections for which mAbs have been added to the therapeutic armamentarium and stressed their potential in representing a readily available protection tool against biothreats and newly emerging and reemerging infectious agents. In reviewing the historical context and main features of mAbs, we assert a potentially wider applicability and cite relevant examples of ongoing therapeutic developments. Factors hindering successful introduction of mAbs on a larger scale are outlined and thoughts are offered on how to possibly address some of these limitations. IMPLICATIONS: mAbs may represent important tools in treating or preventing infections occurring with reasonably sufficient prevalence to justify demand and for which existing alternatives are not deemed fully adequate. Future initiatives need to address the prohibitive costs encountered in the development process. The feasibility of more large-scale administration of alternative modalities merits further exploration. In order to ensure optimal prospect of regulatory success, an early dialogue with competent authorities is encouraged.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Doenças Transmissíveis/terapia , Imunoterapia/tendências , Anti-Infecciosos/uso terapêutico , Anticorpos Monoclonais/efeitos adversos , Ensaios Clínicos como Assunto , Controle de Doenças Transmissíveis/métodos , Aprovação de Drogas , Resistência a Múltiplos Medicamentos , Humanos , Licenciamento
9.
Poult Sci ; 97(7): 2287-2294, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29660058

RESUMO

The maintenance of integrity of the gastrointestinal tract is an important aspect for animal productivity, since it is able to absorb nutrients more efficiently and serves as a barrier against microorganisms. To control agents detrimental to intestinal integrity, growth-promoting antibiotics (AGP) are used, which reduce the number of toxin-producing microorganisms in the intestinal lumen, acting as anti-inflammatory agents. There is a demand for restriction of use of AGP in animal feed, but there are few studies showing what parameters we should observe to search for alternative additives. The aim of this study was to establish histological parameters that explain the effect of enramycin as growth promoter on intestinal health in broilers challenged with Eimeria and Clostridium perfringens. The zootechnical performance and the histology by I See Inside (ISI) methodology were evaluated on liver and ileum samples. Chickens challenged without AGP have the worst BWG, FCR, and histological ISI score (ISI score 9) in the ileum compared to non-challenged (ISI score 5). The use of enramycin on challenged group significantly minimized the ISI score in the ileum at 21 and 28 d (ISI score 7.4 and 8.0, respectively) compared with the challenged group not fed with enramycin (ISI score 9.2 and 9.9, respectively), associated with reduced lamina propria thickness and inflammatory cell infiltration. We suggest these 2 histological parameters as a standard to compare products for gut health.


Assuntos
Galinhas/imunologia , Intestinos/imunologia , Doenças das Aves Domésticas/imunologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/anatomia & histologia , Galinhas/fisiologia , Infecções por Clostridium/imunologia , Infecções por Clostridium/veterinária , Clostridium perfringens/fisiologia , Coccidiose/imunologia , Coccidiose/veterinária , Dieta/veterinária , Suplementos Nutricionais/análise , Eimeria/fisiologia , Intestinos/anatomia & histologia , Intestinos/fisiologia , Masculino , Peptídeos/administração & dosagem , Peptídeos/metabolismo , Distribuição Aleatória
10.
Rev Port Pneumol (2006) ; 23(2): 85-89, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28196610

RESUMO

INTRODUCTION: Lung cancer staging has recently evolved to include endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for nodal assessment. AIM: Evaluate the performance and safety of EBUS-TBNA as a key component of a staging algorithm for non-small cell lung carcinoma (NSCLC) and as a single investigation technique for diagnosis and staging of NSCLC. METHODS: Patients undergoing EBUS-TBNA for NSCLC staging at our institution between April 1, 2010 and December 31, 2014 were consecutively included with prospective data collection. EBUS-TBNA was performed under general anesthesia through a rigid scope. RESULTS: A total of 122 patients, 84.4% males, mean age 64.2 years. Histological type: 78 (63.9%) adenocarcinoma, 33 (27.0%) squamous cell carcinoma, 11 (8.9%) undifferentiated/other NSCLC. A total of 435 lymph node stations were punctured. Median number of nodes per patient was 4. EBUS-TBNA nodal staging: 63 (51.6%) N0; 8 (6.5%) N1; 34 (27.9%) N2, and 17 (13.9%) N3. EBUS-TBNA was the primary diagnostic procedure in 27 (22.1%) patients. EBUS-TBNA NSCLC staging had a sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy rate of 83.3, 100, 100, 86.1, and 91.8%, respectively. No complications were attributable to the procedure. CONCLUSION: A comprehensive lung cancer staging strategy that includes EBUS-TBNA seems to be safe and effective. Our EBUS-TBNA performance and safety in this particular setting was in line with previously published reports. Additionally, our study showed that, in selected patients, lung cancer diagnosis and staging are achievable with a single endoscopic technique.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Brônquios , Carcinoma Pulmonar de Células não Pequenas/secundário , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
11.
Poult Sci ; 96(5): 1078-1087, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27794052

RESUMO

The present study evaluated the effect of aflatoxin B1 and Eimeria vaccine challenges and their interaction on intestinal morphology, applying the morphometric index "I See Inside" (ISI). Immune cellular response and broiler chicken performance were also studied. A total of 240 broiler chickens were divided in a 2 × 2 factorial arrangement with 4 treatments, T1: Control diet and no challenge (CON), T2: Aflatoxin B1 (AFLA), T3: Control diet and Eimeria challenge (COC), and T4: Aflatoxin B1 and Eimeria challenge (AFLA+COC). The mathematical morphometric index ISI was applied to evaluate macro and microscopic alterations. Samples of liver and jejunum were analyzed for macrophages, CD4+, and CD8+ cells counting by immunohistochemistry at 7, 14, and 21 d of age. Chickens challenged with Eimeria presented higher ISI of macroscopic alterations associated to Eimeria lesion at the medium small intestine, lower body weight gain (BWG) and feed intake (FI), and worse feed conversion ratio compared to non-challenged birds. Both Eimeria and aflatoxin challenges modulated the immune cells in the jejunum and liver, generally increasing the number of macrophages, CD4+, and CD8+ cells in relation to the control group. Birds from COC and COC+AFLA groups presented higher ISI histological score in the jejunum at 7 and 14 d of age compared to the CON and AFLA groups. The reduction of FI and BWG was correlated to high histological ISI and resulted in a high presence of immune cells in tissues, suggesting immune response demand. The histological ISI had statistical correlation to broiler performance.


Assuntos
Aflatoxina B1/toxicidade , Galinhas , Coccidiose/veterinária , Eimeria/imunologia , Intestinos/patologia , Doenças das Aves Domésticas/patologia , Doenças das Aves Domésticas/parasitologia , Ração Animal/toxicidade , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Coccidiose/patologia , Eimeria/patogenicidade , Contaminação de Alimentos , Intestinos/imunologia , Intestinos/parasitologia , Fígado/imunologia , Masculino , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/efeitos adversos , Aumento de Peso
15.
Vet Microbiol ; 160(3-4): 530-4, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-22771208

RESUMO

Bordetella avium is an opportunistic pathogen that presents tropism for ciliated epithelia, leading to upper respiratory tract disease in turkeys. This agent has also been associated with Lockjaw Syndrome in psittacine birds, but literatures describing the importance of this agent in such species are rare. The purpose of the present study was to report the first outbreak of B. avium infection in juvenile cockatiels demonstrating the Lockjaw Syndrome in Brazil and to investigate the antimicrobial resistance profile and phenotypic and genotypic characteristics of these strains. Surprising, the strains obtained from five infected cockatiel chicks from three different breeders from different Brazilian states showed a clonal relationship using the Pulsed Field Gel Electrophoresis and Single Enzyme Amplified Fragment Length Polymorphism techniques. The virulence potentials of the B. avium strains were assessed using tracheal adherence and cytotoxic effects on a VERO cell monolayer.


Assuntos
Doenças das Aves/microbiologia , Infecções por Bordetella/veterinária , Bordetella avium/genética , Bordetella avium/patogenicidade , Cacatuas/microbiologia , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , Antibacterianos/farmacologia , Infecções por Bordetella/microbiologia , Bordetella avium/efeitos dos fármacos , Brasil , Chlorocebus aethiops , Farmacorresistência Bacteriana , Eletroforese em Gel de Campo Pulsado , Genótipo , Turquia , Células Vero
16.
Res Vet Sci ; 93(2): 1066-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22209018

RESUMO

This study investigated the occurrence of rotavirus infections in ostriches (Struthio camelus) reared in Northern Paraná, Brazil. Fecal (n=66) and serum (n=182) samples from nine farms located in four different cities were analyzed by silver stained-polyacrylamide gel electrophoresis (ss-PAGE), RT-PCR assay, virus isolation, and counterimmunoelectroosmophoresis (CIE). Rotavirus group A seropositivity occurred in 5.49% (10/182) of serum samples of ostriches originated from two farms. Only 9.09% (6/66) of fecal samples from ostriches with diarrhea maintained in one farm were positive by ss-PAGE, RT-PCR, and virus isolation. The G (VP7) and P (VP4) genotypes of rotavirus wild strains isolated in cell culture were determined by multiplex-nested PCR. The genotyping identified two rotavirus strains: G6P[1] and G10P[1]. In three rotavirus strains it was only possible to identify the P type; one strain being P[1] and two strains that presented the combination of P[1]+P[7]. These findings might represent the first characterization of rotavirus in ostriches, and the finding of porcine and bovine-like rotavirus genotypes in ostriches might suggest virus reassortment and possible interspecies transmission.


Assuntos
Doenças das Aves/virologia , Fezes/virologia , Rotavirus/isolamento & purificação , Struthioniformes , Animais , Anticorpos Antivirais/química , Genótipo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/classificação
17.
J Helminthol ; 86(2): 209-14, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21729387

RESUMO

The occurrence of platynosomiasis and intestinal sparganosis is described in feral cats from Grand Cayman, Cayman Islands. Spirometra spp. was observed within the intestine of 18.18% (10/55) of cats; 1.18% (1/55) of cats demonstrated gross and histological manifestation of parasitism by Platynosomum fastosum, but 14.5% (8/55) of cats had the characteristic pathological manifestations of P. fastosum-induced intrahepatic cholangitis without the concomitant presence of the intraductal trematode. Combined parasitism (Spirometra spp. and P. fastosum) was observed in 9.09% (5/55) of feral cats. Significant pathological findings were only associated with the hepatic fluke, P. fastosum, and were grossly characterized by moderate hepatomegaly with enlarged and dilated bile ducts. Examples of cestodes with morphological features characteristic of Spirometra spp. were observed within the small intestine without any associated pathological lesion. The histopathological evaluation of liver fragments revealed chronic intrahepatic cholangitis with and without the associated intraductal trematode, and was characterized by marked periductal fibrosis, adenomatous proliferation of bile duct epithelium, dilation of intrahepatic bile ducts and portal accumulations of inflammatory cells. The occurrence of the cestode in feral cats coupled with factors that are unique to Grand Cayman makes this island the ideal location for sporadic cases of human sparganosis.


Assuntos
Doenças do Gato/parasitologia , Infecções por Cestoides/veterinária , Colangite/veterinária , Platelmintos/isolamento & purificação , Spirometra/isolamento & purificação , Animais , Animais Selvagens , Doenças do Gato/patologia , Gatos , Infecções por Cestoides/parasitologia , Infecções por Cestoides/patologia , Colangite/parasitologia , Colangite/patologia , Coinfecção/parasitologia , Coinfecção/patologia , Coinfecção/veterinária , Feminino , Fígado/patologia , Masculino , Índias Ocidentais
18.
Stress ; 15(2): 138-48, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21801080

RESUMO

The aim of this study was to evaluate vascular and metabolic effects of chronic mild unpredictable stress (CMS) and hypercaloric diet (HD) without carbohydrate supplementation in rats. Male Sprague-Dawley rats were randomly assigned to four groups: Control, HD, CMS, and HD plus CMS. CMS consisted of the application of different stressors for 3 weeks. The rats were killed 15 days after CMS exposure. The HD group presented higher plasma lipid concentrations, without changes in fasting glucose concentration, glucose tolerance test, and vascular function and morphology, in comparison with the control group. Stressed rats presented higher fasting blood concentration of insulin, higher homeostasis model assessment index values and area under the curve in an oral glucose tolerance test, in comparison with non-stressed rats. CMS increased the plasma concentrations of corticosterone and lipids, and the atherogenic index values, without change in high-density lipoprotein level. CMS increased intima-media thickness and induced endothelium-dependent supersensitivity to phenylephrine, and lowered the relaxation response to acetylcholine in the thoracic aorta isolated from rats fed with control or HD, in comparison with non-stressed groups. CMS effects were independent of diet. In non-stressed rats, the HD induced dyslipidemia, but did not change glucose metabolism, vascular function, or morphology. The data from this study indicate that CMS promotes a set of events which together can contribute to impair function of the thoracic aorta.


Assuntos
Dieta Hiperlipídica , Estresse Psicológico/sangue , Estresse Psicológico/fisiopatologia , Vasodilatação , Acetilcolina/farmacologia , Animais , Aorta Torácica/efeitos dos fármacos , Glicemia/metabolismo , Corticosterona/sangue , Dieta Hiperlipídica/efeitos adversos , Jejum/fisiologia , Teste de Tolerância a Glucose , Insulina/sangue , Lipídeos/sangue , Lipoproteínas HDL/sangue , Masculino , Fenilefrina/farmacologia , Ratos , Ratos Sprague-Dawley
19.
Braz. j. biol ; 68(4,supl): 1039-1050, Nov. 2008.
Artigo em Inglês | LILACS | ID: lil-504456

RESUMO

Human activities have a considerable impact on hydrographic systems and fish fauna. The present review on conservation genetics of neotropical freshwater fish reveals that DNA analyses have been promoting increased knowledge on the genetic structure of fish species and their response to environmental changes. This knowledge is fundamental to the management of wild fish populations and the establishment of Evolutionary Significant Units capable of conserving genetic integrity. While population structuring can occur even in long-distance migratory fish, isolated populations can show reduced genetic variation and be at greater risk of extinction. Phylogeography and phylogeny have been powerful tools in understanding the evolution of fish populations, species and communities in distinct neotropic environments. Captive fish can be used to introduce new individuals and genes into the wild and their benefits and disadvantages can be monitored through genetic analysis. Understanding how fish biodiversity in neotropical freshwaters is generated and maintained is highly important, as these habitats are transformed by human development and fish communities are increasingly exploited as food sources to sustain a growing human population.


Atividades humanas têm um grande impacto sobre os sistemas hidrográficos e a fauna de peixes. A presente revisão em genética da conservação dos peixes de água doce neotropicais revela que as análises de DNA têm promovido um crescimento no conhecimento da estrutura genética das espécies e suas respostas às alterações ambientais. Este conhecimento é fundamental para o manejo das populações de peixes nativos e para o estabelecimento de Unidades Evolutivas Significantes capazes de conservar a integridade genética dessas populações. Enquanto o fenômeno de estruturação de populações pode ocorrer mesmo em peixes migradores de longas distâncias, populações isoladas podem mostrar reduzida variação genética e apresentar grande risco de extinção. Em adição, a filogeografia e a filogenia têm dado importantes contribuições para o entendimento da evolução das populações, espécies e comunidades de peixes em distintos ambientes neotropicais. Populações de cativeiro podem ser utilizadas como fonte de introdução de novos indivíduos e genes no ambiente natural e seus benefícios e desvantagens podem ser monitorados por meio de análises genéticas. É altamente importante, portanto, entender como é gerada e mantida a biodiversidade de peixes de água doce neotropicais, uma vez que os habitats são transformados pelo desenvolvimento humano e as comunidades de peixes têm sido intensamente exploradas como alimento de sustentação desse crescimento das populações humanas.


Assuntos
Animais , Humanos , Biodiversidade , Conservação dos Recursos Naturais , Água Doce , Peixes/genética , Biologia Molecular , Clima Tropical , DNA , Peixes/classificação , Marcadores Genéticos , Variação Genética , Filogenia , Densidade Demográfica
20.
Braz. j. biol ; 68(4)Nov. 2008.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467958

RESUMO

Human activities have a considerable impact on hydrographic systems and fish fauna. The present review on conservation genetics of neotropical freshwater fish reveals that DNA analyses have been promoting increased knowledge on the genetic structure of fish species and their response to environmental changes. This knowledge is fundamental to the management of wild fish populations and the establishment of Evolutionary Significant Units capable of conserving genetic integrity. While population structuring can occur even in long-distance migratory fish, isolated populations can show reduced genetic variation and be at greater risk of extinction. Phylogeography and phylogeny have been powerful tools in understanding the evolution of fish populations, species and communities in distinct neotropic environments. Captive fish can be used to introduce new individuals and genes into the wild and their benefits and disadvantages can be monitored through genetic analysis. Understanding how fish biodiversity in neotropical freshwaters is generated and maintained is highly important, as these habitats are transformed by human development and fish communities are increasingly exploited as food sources to sustain a growing human population.


Atividades humanas têm um grande impacto sobre os sistemas hidrográficos e a fauna de peixes. A presente revisão em genética da conservação dos peixes de água doce neotropicais revela que as análises de DNA têm promovido um crescimento no conhecimento da estrutura genética das espécies e suas respostas às alterações ambientais. Este conhecimento é fundamental para o manejo das populações de peixes nativos e para o estabelecimento de Unidades Evolutivas Significantes capazes de conservar a integridade genética dessas populações. Enquanto o fenômeno de estruturação de populações pode ocorrer mesmo em peixes migradores de longas distâncias, populações isoladas podem mostrar reduzida variação genética e apresentar grande risco de extinção. Em adição, a filogeografia e a filogenia têm dado importantes contribuições para o entendimento da evolução das populações, espécies e comunidades de peixes em distintos ambientes neotropicais. Populações de cativeiro podem ser utilizadas como fonte de introdução de novos indivíduos e genes no ambiente natural e seus benefícios e desvantagens podem ser monitorados por meio de análises genéticas. É altamente importante, portanto, entender como é gerada e mantida a biodiversidade de peixes de água doce neotropicais, uma vez que os habitats são transformados pelo desenvolvimento humano e as comunidades de peixes têm sido intensamente exploradas como alimento de sustentação desse crescimento das populações humanas.

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