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1.
Braz J Biol ; 84: e279881, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422299

RESUMO

Understanding how functionally similar species segregate resources to minimize competition is vital for predicting evolutionary factors and patterns of coexistence. We conducted a study in Mata de Itamacaoca, in the middle Munim River basin, Maranhão, northeastern Brazil, to characterize the functional morphology and trophic niches of five coexisting Characiform species in this area - including a recently described species, and to investigate whether their functional morphology is a key determinant of their trophic niches. Our analysis of functional morphology and diet, employing linear measurements to predict dietary specializations, showed that these species are predominantly generalist insectivores with a significant morphological overlap. This study underscores the influence of species' natural history on their ecological characteristics, contributing to more effective conservation strategies.


Assuntos
Cadeia Alimentar , Rios , Animais , Brasil , Peixes , Dieta
2.
Braz J Biol ; 83: e275940, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126638

RESUMO

Guarana [Paullinia cupana var. sorbilis (Mart.) Ducke] is a species of great economic and social important in Brazil, as it is the only commercial guarana producer in the world. The vegetative propagation method indicated for the culture is stem cuttings, which aims at productivity, tolerance, and uniformity of clonal cultivars, because reproduction by seeds has slow germination and high genetic variability, which in traditional varieties is an undesirable factor. Genetic factors can interfere with the rooting capacity of the crop. Studies seek alternatives that can improve this condition and enhance the production system. Use of growth regulators, microorganisms that promote plant growth, variation of substrates and fertilization, have been strategies used. Preliminary tests on the rate of stem rooting and seed germination with the use of exogenous phytohormone did not demonstrate in relation to the non-application of these inducers. The use of rhizobacteria, which presents itself as a promising activity in many cultures, has not yet been demonstrated in the culture of guarana. On the other hand, the influence of different substrates on rooting has already shown consistent results as a function of rooting rate. Fertilizing the mother plants as recommended by the production system for the crop has proven to be an efficient procedure. There are still few studies aimed at improving the spread of guarana, demonstrating that new protocols need to be explored, or that the protocols already used are reviewed from another perspective.


Assuntos
Paullinia , Paullinia/química , Paullinia/genética , Sementes , Brasil , Reprodução
3.
Osteoporos Int ; 34(11): 1881-1891, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37418151

RESUMO

Realising the benefits of systematic secondary fracture prevention requires supporting local sites to get started and becoming effective. We here describe the development, implementation and impact of a regional fracture liaison service (FLS) mentorship programme in Latin America that led to 64 FLS getting started and coverage of 17,205 patients. INTRODUCTION: Despite treatments and service models to deliver effective secondary fracture prevention, most patients are left untreated after a fragility fracture. To improve the capability to get FLS started and more effective, we describe the development, implementation and evaluation of an international programme to develop national communities of FLS mentors as part of the Capture the Fracture Partnership in Latin America. METHODS: The IOF regional team and the University of Oxford developed the curriculum and associated resources for training mentors in setting up FLS, service improvement and mentorship. Mentors were selected during a preparatory meeting, trained using live online sessions followed by regular mentor-led post-training meetings. The programme was evaluated using a pre-training needs assessment and post-training evaluation based on Moore's outcomes. RESULTS: The mentorship programme was initiated in Mexico, Brazil, Colombia and Argentina. The mentors were multidisciplinary, including orthopaedic surgery, rehabilitation, rheumatology, endocrinology, geriatrics, gynaecology and internal medicine. There was 100% participation in training sessions and reported satisfaction with the training. Since the initiation of the training programme, 22 FLS have been set up in Mexico, 30 in Brazil, 3 in Colombia and 9 in Argentina, in comparison with two in Chile and none in any other LATAM countries that were not involved in the mentorship programme. This equates to approximately 17,025 additional patients identified from 2019 to 2021 after initiation of mentorship. The mentors have engaged with 58 FLS for service development. Post-training activities include two published national best practice guidelines and other country-specific resources for FLS in the local language. CONCLUSION: Despite the COVID pandemic, the mentorship pillar of the Capture the Fracture Partnership has developed a community of FLS mentors with measurable improvement in national FLS provision. The programme is a potentially scalable platform to develop communities of mentors in other countries.


Assuntos
COVID-19 , Fraturas por Osteoporose , Humanos , Fraturas por Osteoporose/prevenção & controle , Mentores , América Latina , México , Prevenção Secundária
4.
Arq. bras. med. vet. zootec. (Online) ; 75(2): 174-184, Mar.-Apr. 2023. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1427470

RESUMO

The aim of this study was to describe the clinical and morphological characteristics of mixed mammary neoplasms and verify what characteristics affect the prognosis of female dogs with carcinomas in mixed tumors and carcinosarcomas. This was a retrospective study of 67 female dogs that underwent mastectomies and were diagnosed with benign mixed tumors (n=13), carcinomas in mixed tumors (n=44) and carcinosarcomas (n=10). Data regarding the clinical and histological aspects of the neoplasms were collected and the relation with specific survival times, and hazard ratios (HR) in 24 months was calculated. In univariate analysis, the diagnosis of carcinosarcoma (HR 8.26, p=0.006), carcinomatous areas with micropapillary or solid patterns (HR 17.49; p=0. 001) and lymph node metastasis (HR 7.07;p=0.020) were associated with specific survival. In multivariable analysis, only micropapillary or solid pattern (HR=16.34; p=0.007) remained independent factor associated with lower specific survival. Micropapillary or solid carcinomatous patterns were associated with shorter specific survival time (p=0.002) among animals with carcinomas in mixed tumors. Among the carcinosarcomas, lymph node metastasis (p=0.010) was associated with a shorter specific survival time. In conclusion, carcinomas in mixed tumors and carcinosarcomas vary in prognosis depending on the carcinomatous proliferation patterns and spread of the disease.


O objetivo deste estudo foi descrever as características clínicas e morfológicas das neoplasias mamárias mistas e verificar quais características interferem no prognóstico de cadelas com carcinomas em tumores mistos e carcinossarcomas. Este foi um estudo retrospectivo de 67 cadelas, que foram submetidas a mastectomias e diagnosticadas com tumores mistos benignos (n = 13), carcinomas em tumores mistos (n = 44) e carcinossarcomas (n = 10). Foram coletados dados sobre os aspectos clínicos e histológicos das neoplasias e a relação com o tempo de sobrevida específica e a razão de risco (OR) em 24 meses foram calculadas. Na análise univariada, o diagnóstico de carcinossarcoma (HR 8,26; p=0,006), as áreas carcinomatosas com padrão micropapilar e sólido (HR 17,49; p= 0,001) e metástase linfonodal (HR 7,07; p=0,020) foram associadas à menor sobrevida específica. Na análise multivariável, apenas o padrão micropapilar ou sólido (HR=16,34; p=0,007) permaneceu como fator independente associado à sobrevida. Proliferações carcinomatosas micropapilares ou sólidas (p = 0,002) foram associadas a tempos de sobrevida específica mais curtos entre os animais com carcinomas em tumor misto. Entre os pacientes com carcinossarcoma, metástases em linfonodos (p = 0,010) foram associadas a um menor tempo de sobrevida específica. Em conclusão, os resultados mostraram que os carcinomas em tumores mistos e os carcinossarcomas podem ter prognóstico variável, dependendo do padrão de proliferação carcinomatosa e da disseminação linfática da doença.


Assuntos
Animais , Cães , Prognóstico , Neoplasias da Mama/veterinária , Carcinossarcoma/veterinária , Doenças do Cão
5.
Immunobiology ; 227(6): 152284, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36191584

RESUMO

Asthma is a disorder characterized by airflow obstruction, inflammation, declining airway function, bronchial hyperresponsiveness and tissue remodelling. Probiotics are defined as "live microorganisms that, when administered in adequate amounts, confer a health benefit on the host". The use of probiotics is becoming increasingly studied and recent evidence has suggested that it may provide therapeutic benefits in asthma and other diseases. Lactobacillus delbrueckii UFV-H2b20 fulfils all the requirements to be classified as probiotic. Previous studies have already shown the ability of L. delbrueckii UFV-H2b20 to stimulate the immune system. Our objective was to evaluate the protective effects of L. delbrueckii UFV-H2b20 in experimental allergic asthma. We used a murine model of ovalbumin-induced allergic airway inflammation to mimic allergic asthma. Oral treatment with L. delbrueckii UFV-H2b20 improves respiratory parameters and inhibits the inflammatory response in the lungs by decreasing the numbers of inflammatory monocytes, eosinophils and alveolar macrophages, as well as IgE levels. Treatment increased the IFN-γ/IL-4 cytokine ratio. Levels of IL-10 in the lungs were also increased in treated animals. Our results also showed that the probiotic administration increases the number of CD39+CD73+ T regulatory lymphocytes in the lung, suggesting a role for purinergic signals in the regulation of inflammation promoted by the treatment. Understanding the mechanisms of modulation of the immune system by probiotics could allow the development of probiotic preparations that are safe and have a direct action. Our results suggest that oral administration of L. delbrueckii UFV-H2b20 could be helpful to treat chronic inflammatory airway diseases, such as asthma.


Assuntos
Asma , Lactobacillus delbrueckii , Probióticos , Animais , Camundongos , Asma/terapia , Líquido da Lavagem Broncoalveolar , Contagem de Células , Citocinas/farmacologia , Modelos Animais de Doenças , Inflamação , Interferon gama/metabolismo , Lactobacillus delbrueckii/fisiologia , Pulmão , Camundongos Endogâmicos BALB C , Ovalbumina , Linfócitos T Reguladores
6.
Radiat Prot Dosimetry ; 198(7): 379-385, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35512350

RESUMO

This work establishes local diagnostic reference levels (DRLs) in interventional radiology based on adult patient body mass index (BMI). The monitoring was carried out from 23 institutions and patient data from 3015 procedures were collected, being 907 Catheterism (CAT), 921 Percutaneous transluminal coronary angioplasty (PTCA) and 1187 CAT/PTCA and 6 BMI ranges were taken, going from under 18 up to 40 kg·m-2. It is presented that 18 initial DRL values to be used in the county of Minas Gerais. The overall 75th kerma-area product (KAP), commonly considered DRL, in Gy·cm2, is 94.6(SD 119)-CAT, 88.6(SD 121)-PTCA and 33.0(SD 47.6)-CAT/PTCA. In considering KAP-BMI individual values, one obtain the min-max ranges, in Gy·cm2, 3.2-BMI A to 101-BMI B for CAT, 65-BMI A to 102-BMI F for PTCA and 10.4-BMI A to 59.2-BMI E for CAT/PTCA. The KAP-BMI approach has shown to be feasible as a DRL optimization process.


Assuntos
Níveis de Referência de Diagnóstico , Radiografia Intervencionista , Índice de Massa Corporal , Brasil , Angiografia Coronária , Fluoroscopia , Humanos , Doses de Radiação , Radiografia Intervencionista/métodos
7.
Theriogenology ; 178: 60-66, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34775200

RESUMO

5 fluorouracil (5FU), an antineoplastic drug, is often utilized in the therapeutic regimen for several types of cancer, including the hepatoblastoma in children. The effects of 5FU on the population of ovarian preantral follicles, which is the largest oocyte reservoir, is still poorly understood. The integrity of the ovarian preantral follicle pool is important for lifelong fertility. The better understanding of such effects may favor intervention strategies to protect fertility in 5FU-treated children and women coping with cancer. To analyze the effects of 5FU on isolated murine secondary follicles in vitro, ovaries were collected from young mice (28-30 days old), and secondary follicles were isolated and cultured for 12 days in basic culture medium, with or without 5FU at concentrations of 0.3 mM, 1 mM, 3 mM, 10 mM, and 30 mM. In the in vitro study, we analyzed the percentage of morphologically normal follicles, antrum formation, follicular diameter, and hormone production. On day 12, oocytes were recovered for in vitro maturation. 5FU treatment did not alter the percentage of morphologically normal follicles. On day 12, only 1, 10, and 30 mM 5FU significantly reduced the percentage of antrum. From day 4 onwards, 5FU treatments significantly reduced follicle diameter. The meiosis resumption rate was significantly lower in all 5FU treatments. 5FU concentrations ≥3 mM reduced estradiol levels. In conclusion, 5FU does not affect follicular morphology. However, 5FU deleteriously affects follicular growth, estradiol production, and oocyte maturation in isolated ovarian follicles.


Assuntos
Antineoplásicos , Fluoruracila , Animais , Feminino , Fluoruracila/farmacologia , Meiose , Camundongos , Oócitos , Folículo Ovariano
8.
Nutr Neurosci ; 25(11): 2442-2457, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34514962

RESUMO

Objectives: The mechanism behind the progression of Mild Cognitive Impairment (MCI) to Alzheimer's disease (AD) remains poorly understood. However some evidence pointed out that the co-occurrence of metabolic conditions affecting glucose homeostasis, as type 2 diabetes mellitus (T2DM), may be an important catalyst in this context. Notably, candidate drugs which modulate common pathways in the development of MCI-to-AD mediated by T2DM may offer likely therapy for AD. Nonetheless, limited pharmacological alternatives that modulate common pathways in T2DM, MCI, and AD are available. In the recent decades, studies have shown that resveratrol may act as a neuroprotective compound, but little is known about its potential in improving cognitive and metabolic aspects associated with AD progression mediated by the co-association between TDM2-MCI.Methods: In this review, we discuss possible protective mechanisms of resveratrol on shared pathways associated with AD progression mediated by T2DM-MCI co-occurrence.Results: Some studies indicated that insulin resistance and hyperglycemia may be also a T2DM risk factor for the progression of MCI-to-AD, promoting alterations in metabolic pathways associated with neuronal plasticity, and increasing pro-inflammatory environment. Interestingly, basic research and clinical trials indicate that resveratrol may modulate those pathways, showing a potential neuroprotective effect of this polyphenol.Conclusion: Therefore, there is not enough clinical data supporting the translational therapeutic use of resveratrol in this scenario.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Doenças Neurodegenerativas , Humanos , Resveratrol/uso terapêutico , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/prevenção & controle , Doença de Alzheimer/complicações , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/complicações
14.
Neuropeptides ; 83: 102081, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32839009

RESUMO

Gyroxin is a thrombin-like toxin obtained from the venom of the South American rattlesnake, Crotalus durissus terrificus. Literature has reported "gyroxin syndrome" characterized, in mice, as series of aberrant motor behavior, known as barrel rotation, mainly after intraperitoneal administration. Despites several studies, a physiological mechanism of "gyroxin syndrome" are still not completely understood. In this context, alterations on the central nervous system (CNS), especially causing neurotoxic events, are pointed out as likely candidates. Then, we decided to investigate whether gyroxin induces alterations in glutamate release, one of the most important neurotransmitter involved in neurotoxicity. For that, we performed all experiments, in vitro, using a model of mice brain cortical synaptosomes. Notably, our results indicate that the administration of gyroxin on purified presynaptic brain cortical terminals resulted in an extracellular Ca2+- dependent raise in glutamate release. Indeed, our results also showed that gyroxin increases intrasynaptosomal calcium (Ca2+) levels through acting on voltage gated calcium channels (VGCC), specifically N and P/Q subtypes. Moreover, our data show that gyroxin increases exocytosis rate. Interestingly, these data suggest that gyroxin might induce neurotoxicity by increasing glutamate levels. However, future investigations are needed in order to elucidate the nature of the following events.


Assuntos
Cálcio/metabolismo , Córtex Cerebral/efeitos dos fármacos , Venenos de Crotalídeos/farmacologia , Ácido Glutâmico/metabolismo , Neurotoxinas/farmacologia , Sinaptossomos/efeitos dos fármacos , Animais , Córtex Cerebral/metabolismo , Camundongos , Sinaptossomos/metabolismo
15.
Fam Pract ; 37(1): 69-80, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-31433473

RESUMO

BACKGROUND: Brazil is the most populous country with a public, universal and free health care system. The National Program for Access and Quality Improvement in Primary Care (PMAQ) was created to improve the quality of primary health care (PHC). OBJECTIVE: To evaluated whether progress generally has been made within Brazil's PHC since PMAQ implementation, and if changes occurred uniformly in the country, while also identifying municipal characteristics that may have influenced the improvement. METHODS: This is an observational study using data from PMAQ external evaluation (2012 and 2014), a 1200-item survey used to evaluate Brazilian PHC quality. After confirming the groupings of items using factor analysis, we created 23 composed indexes (CIs) related to infrastructure and work process. RESULTS: On average, the large majority of CIs showed improvements between 2012 and 2014. Region and city size moderated changes in the PHC indices differently. Overall, there were better improvements in infrastructure in the Northeast compared with other country regions, and in smaller cities (10 000-20 000 people). Infrastructure indices appear to have improved equitably across the country. Work process improvements varied with city size and region. CONCLUSION: Despite similar support of PMAQ across the country, improvements are not predictable nor homogeneous. Non-uniform improvements were seen in Brazil's PHC. Though we do not directly evaluate the effectiveness of the PMAQ (financial reward) method, these initial findings suggest that it is a potentially useful tool to improve health systems, but additional support may be needed in regions that lag behind in quality improvements.


Assuntos
Política de Saúde , Acessibilidade aos Serviços de Saúde , Atenção Primária à Saúde/normas , Avaliação de Programas e Projetos de Saúde , Melhoria de Qualidade/normas , Assistência de Saúde Universal , Brasil , Humanos
16.
Biochem Mol Biol Educ ; 47(6): 672-680, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31587483

RESUMO

This article examines student engagement in an inquiry-based learning activity, planned to provide students with elements in the social, epistemic, and conceptual dimensions related to the scientific practice in immunology. The activity was applied to 39 groups of students enrolled in immunology or biochemistry courses in a public university in Brazil. Students performed data-collection through the execution of an in vitro assay. We analyzed how students represent data and use them to support their claims in their written constructs. To clarify which are the productive epistemologies in students' reports, we developed a framework for epistemic practice analysis. Our findings point to a pattern of several epistemic practice categories in their written text, mostly related to the particular contingences of data analysis, rather than to theoretical concepts. In addition, we observed that students performed literary inscriptions to represent their data; however, they tended not to cite all data obtained in their written texts. These results suggest that immunology education strategies should provide students with approaches that explore the role of data representation in the scientific text rhetoric. © 2019 International Union of Biochemistry and Molecular Biology, 47(6):672-680, 2019.


Assuntos
Alergia e Imunologia/educação , Aprendizagem , Brasil , Currículo , Avaliação Educacional , Humanos , Conformação Proteica , Estudantes , Universidades
17.
Phys Rev E ; 100(1-1): 012217, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31499878

RESUMO

Solar systems complexity, multiscale, and nonlinearity are governed by numerous and continuous changes where the sun magnetic fields can successfully represent many of these phenomena. Thus, nonlinear tools to study these challenging systems are required. The dynamic system recurrence approach has been successfully used to deal with this kind challenge in many scientific areas, objectively improving the recognition of state changes, randomness, and degrees of complexity that are not easily identified by traditional techniques. In this work we introduce the use of these techniques in photospheric magnetogram series. We employ a combination of recurrence quantification analysis with a preprocessing denoising wavelet analysis to characterize the complexity of the magnetic flux emergence in the solar photosphere. In particular, with the developed approach, we identify regions of evolving magnetic flux and where they present a large degree of complexity, i.e., where predictability is low, intermittence is high, and low organization is present.

18.
Int Endod J ; 52(10): 1457-1465, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31046128

RESUMO

AIM: To analyse longitudinally the immune-inflammatory response in teeth of mice that underwent a regenerative protocol with or without the use of ethylenediaminetetraacetic acid (EDTA) to irrigate the root canal system. METHODOLOGY: First maxillary molars of mice were devitalized using size 10 and 15 files. Teeth were divided into the following groups: Empty - the canals were left empty; Blood Clot (BC) - the canals were filled with a blood clot; and EDTA + Blood - the canals were irrigated with 0.06 mL of 17% EDTA for 1 min and filled with a blood clot. Access cavities were restored with Coltosol® . Animals were sacrificed at 7, 14 or 21 days after the operative procedures, and teeth were collected. RNA was extracted, mRNA expression of the cytokines IGF, NGF, IL-1α, IL-10, TGF and VEGF was assessed using real-time PCR, and the anova Kruskal-Wallis test was used. RESULTS: IL-1 mRNA expression was significantly higher in the EDTA + BC group than in the Empty and BC groups at the 7th and 14th days of evaluation (P < 0.05). IL-10 mRNA expression was similar across the three groups at all time periods. TGF-ß mRNA expression in the EDTA + BC group was significantly higher on the 7th and 21st days than on the 14th (P < 0.05); at day 21, TGF-ß mRNA expression was similar between the BC and EDTA + BC groups but significantly higher than in the Empty group (P < 0.05). IGF mRNA expression was significantly higher in the EDTA + BC group than in the other groups at all time periods. VEGF mRNA expression remained unchanged throughout the experimental period in all groups (P > 0.05). NGF mRNA expression was similar amongst all groups at the 7th and 21st days (P > 0.05). At the 14th day, however, there was a significant increase in NGF mRNA expression in the EDTA + Blood group (P < 0.05) when compared with the expression in the other groups. CONCLUSION: EDTA promoted increased expression of factors that have the potential to improve the outcome of regenerative endodontic treatment.


Assuntos
Endodontia Regenerativa , Irrigantes do Canal Radicular , Animais , Ácido Edético , Camundongos , Dente Molar , Tratamento do Canal Radicular
19.
Neotrop Entomol ; 48(3): 391-398, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30617739

RESUMO

Parasitoid fitness is strongly influenced by host quality for immature parasitoid development and by oviposition host choice patterns made by adult female parasitoids. This study aimed to determine immature host quality of Schizaphis graminum (Rondani) (Hemiptera: Aphididae) and Lysiphlebus testaceipes (Cresson) (Hymenoptera: Braconidae) host instars preference. To this end, the host quality of immature stages of S. graminum was assessed by rearing the parasitoid in all four instars of the aphid, placing each nymph stage of the aphid parasitized by L. testaceipes in separate Petri dishes with sorghum leaves over a 1% agar-water solution at 23 ± 1°C and a 12:12 h L:D photoperiod. The host-age preferences of the parasitoid between second and fourth instar nymphs were analyzed by choice (ten nymphs of each instar) and non-choice (ten nymphs of one instar) tests, observing parasitoid foraging in a 5-cm arena for 5 min under a stereoscopic microscope. Third and fourth instars were better hosts than first or second instars, with faster developmental times, resulting in larger wasps with bigger hind tibia size and more eggs in their ovarioles (i.e., higher initial egg load). Females preferred to oviposit in fourth instar aphids in both choice and non-choice tests. Selection by adult L. testaceipes females of older instars of S. graminum for oviposition maximizes parasitoid fitness as these instars are intrinsically more suitable for development of parasitoid offspring.


Assuntos
Afídeos/parasitologia , Especificidade de Hospedeiro , Vespas/fisiologia , Animais , Afídeos/crescimento & desenvolvimento , Feminino , Masculino , Ninfa/parasitologia , Oviposição
20.
Res Vet Sci ; 122: 22-28, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30448391

RESUMO

This study investigated: 1) the kinetics of oocyte chromatin configuration during in vitro maturation (IVM) of caprine and bovine oocytes; and 2) the effect of in vitro pre-maturation (IVPM) with cilostamide with or without association of the follicular wall (FW) on the same parameters. In experiment I, cumulus-oocyte complexes (COCs) were cultured in vitro in a standard maturation medium for 6, 12, 18 or 30 h. For experiment II, the COCs were cultured for 30 h, either in a standard IVM medium or in IVPM containing cilostamide (10 or 20 µM) and FW alone or in combination, for 6 or 12 h before the onset of maturation. The MII rate was similar (P > .05) between 18 and 30 h of maturation, both of which were higher (P < .05) than 6 and 12 h IVM in both species (Experiment I). Contrary to caprine, all IVPM treatments presented a higher (P < .05) percentage of bovine oocytes arrested at the GV stage than the control treatment after 6 h of culture. The percentage of MII oocytes after 30 h (IVPM+IVM) of culture in bovine oocytes treated with 10 µM cilostamide associated with FW and FW alone cultured for 6 h presented MII percentages similar to the control. However, in caprine, these treatments significantly reduced the percentages of MII in relation to the control treatment (Experiment II). In conclusion, the combination of concentration-exposure time to cilostamide during IVPM delayed meiotic progression in bovine after 6 and 12 h of culture. However, overall the culture period (IVPM+IVM) influenced the oocyte chromatin configuration and kinetics in both species.


Assuntos
Bovinos , Cabras , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/efeitos dos fármacos , Quinolonas/farmacologia , Animais , Feminino , Técnicas de Maturação in Vitro de Oócitos/métodos , Cinética , Meiose , Oócitos/fisiologia
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