Pesquisa | SciELO

Resumo O conteúdo de dopamina nas estruturas cerebrais tem sido relacionado à excitabilidade neuronal e várias abordagens têm sido utilizadas para estudar este fenômeno durante o período de vulnerabilidade às crises. No presente trabalho, descrevemos os efeitos da depleção de dopamina após a administração de 6-hidroxidopamina (6-OHDA) na região pars compacta da substância negra de ratos submetidos ao modelo de epilepsia com pilocarpina. A susceptibilidade ao estado de mal epiléptico induzido pela pilocarpina, bem como a frequência de crises espontâneas e recorrentes durante o período crônico do modelo foi determinada. Sendo o hipocampo uma das principais estruturas afetadas no desenvolvimento desse modelo experimental de epilepsia, os níveis de dopamina nessa região foram determinados após a administração da droga. No primeiro experimento, 62% (15/24) dos ratos pré-tratados com 6-OHDA e 45% (11/24) daqueles que receberam ácido ascórbico como solução controle evoluíram para crises límbicas motoras e para o estado de mal epiléptico, após a administração de pilocarpina. A gravidade das crises durante o período agudo do modelo foi significativamente maior nos ratos epilépticos experimentais (56,52%) do que nos ratos controle (4,16%). No segundo experimento, não houve diferença significante entre os grupos quanto à frequência de crises na fase crônica do modelo. Nossos dados mostraram que a dopamina pode desempenhar um papel importante na gravidade das crises na fase aguda da pilo, o que parece ser exercido por sua ação inibitória da dopamina sobre a expressão motora das crises.

Abstract The dopamine content in cerebral structures has been related to neuronal excitability and several approaches have been used to study this phenomenon during seizure vulnerability period. In the present work, we describe the effects of dopamine depletion after the administration of 6-hidroxidopamine (6-OHDA) into the substantia nigra pars compacta of male rats submitted to the pilocarpine model of epilepsy. Susceptibility to pilocarpine-induced status epilepticus (SE), as well as spontaneous and recurrent seizures (SRSs) frequency during the chronic period of the model were determined. Since the hippocampus is one of main structures in the development of this experimental model of epilepsy, the dopamine levels in this region were also determined after drug administration. In the first experiment, 62% (15/24) of 6-OHDA pre-treated rats and 45% (11/24) of those receiving ascorbic acid as control solution progressed to motor limbic seizures evolving to SE, after the administration of pilocarpine. Severeness of seizures during the model´s the acute period, was significantly higher in epileptic experimental rats (56.52%), than in controls (4.16%). In the second experiment, the frequency of seizures in the model’s chronic phase did not significantly change between groups. Our data show that dopamine may play an important role on seizure severity in the pilo’s model acute period, which seems to be due to dopamine inhibitory action on motor expression of seizure.

https://doi.org/10.1590/1519-6984.248411

T2-hyperintensity in the internal globus pallidus in Machado-Joseph disease T2hyperintensity Thyperintensity T2 hyperintensity T MachadoJoseph Machado Joseph
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Meira, Alex T.

; Araruna, Jorge E. D.

; Araujo, Lais Vieira

; Leite, Raíssa N. L. F.

; Franklin, Gustavo L.

; Nepomuceno, Adriana M. T.

; Teive, Hélio A. G.

Arquivos de Neuro-Psiquiatria

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Nov 2023, Volume 81 Nº 11 Páginas 1018 - 1019

Resumo: En | Texto: En | PDF: En

https://doi.org/10.1055/s-0043-1772605

COVID-19 Infection Changes the Functions and Morphology of Erythrocytes: A Multidisciplinary Study
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Sales, Marcos V. S.

; Tanabe, Eloiza L. L.

; Maciel, Thamilla M. S.

; Tavares, Maria C.

; Leal, Juliana G. C.

; Pinto, Larissa S.

; Pires, Keyla S. N.

; Coelho, Jorge A. P. M.

; Silva, Elaine C. O.

; Souza, Samuel T.

; Fonseca, Eduardo J. S.

; Fragoso, Thiago S.

; Aquino, Thiago M.

; Borbely, Alexandre U.

; Rocha, Ueslen

; Santos, Josué C. C.

; Leite, Ana Catarina R.

Journal of the Brazilian Chemical Society

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Ago 2023, Volume 34 Nº 8 Páginas 1185 - 1196

Resumo: En | Texto: En | PDF: En

Hematological problems are associated with Coronavirus disease 2019 (COVID-19). Respiratory impairment is the higher point studied, although without experimental studies related to the oxygen transport performed by erythrocytes. Therefore, we decided to investigate if erythrocytes from COVID-19 patients have their functionality changed. The case-control study included hospitalized patients with a positive real-time polymerase chain reaction (RT-PCR) result admitted to University Hospital. Volunteers (negative RT-PCR results) were recruited as a control group. Thus, we assessed different erythrocytes parameters, oxidative stress markers, and biophysical studies using whole blood and isolated hemoglobin. We found a decrease of 51% in oxygen uptake and reduced antioxidant enzyme activity in COVID-19 patients compared to controls. Raman spectrometry showed structural changes in the hemoglobin and lipids of the erythrocytes from COVID-19 patients; thus, these results were consolidated with an increase in Young’s modulus in erythrocytes followed by morphology changes. Besides, isolated hemoglobin from COVID-19 patients has a distinct interaction profile using a ligand model compared to the control. COVID-19 leads to structural, functional, and morphological damage to human erythrocytes. Our data showed structural and molecular changes and induction of oxidative stress in erythrocytes by COVID-19, a new perspective on the contribution of erythrocytes to a respiratory commitment in COVID-19.

https://doi.org/10.21577/0103-5053.20230031

Anti-Toxoplasma gondii and anti-Neospora caninum antibodies in dogs with and without neurological signs
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Caramalac, Silvana Marques

; Caramalac, Simone Marques

; Leite, Bets-Saba Naate Naumann Cerqueira

; Castilho, Pablo Menegon

; Minutti, Ana Flávia

; Martins, Thais Agostinho

; Garcia, João Luis

; Barros, Luiz Daniel de

; Romão, Felipe Gazza

; Palumbo, Mariana Isa Poci

Ciência Rural

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2023, Volume 53 Nº 9 elocation e20220133

Resumo: En Pt | Texto: En Pt | PDF: En | PDF: Pt

ABSTRACT: This study investigated the association between neurological signs as well as plausible risk factors and the seroprevalence of Toxoplasma gondii and Neospora caninum infection in dogs of the Campo Grande region of Mato Grosso do Sul, Brazil. In this study, the dogs were divided into two groups based on the presence and the absence of neurological signs (n=30 in each group). Serological diagnosis was performed using the indirect fluorescent antibody test. In the group with neurological disorders, 23.3% and 30% of the dogs had anti-T. gondii and anti-N. caninum antibodies, respectively. Moreover, three dogs from this group showed co-infection with both protozoa. In the group without neurological signs, 16.7% and 13.3% of the dogs were seropositive for T. gondii and N. caninum, respectively. Although presence of neurological signs was not associated with T. gondii and N. caninum infections (P = 0.747 and P = 0.21, respectively), there was a statistical association between T. gondii seropositivity and peripheral neurological alteration (P = 0.016) among dogs with neurological signs. Raw meat ingestion was the only risk factor associated with the presence of anti-N. caninum antibodies (P = 0.041). Results revealed evidence of exposure to N. caninum and T. gondii in dogs irrespective of the presence of neurological signs. Moreover, this study highlighted the need for serological investigation of T. gondii in dogs with disturbances in peripheral nervous systems and not offering raw meat to animals to avoid the risk of N. caninum infection.

RESUMO: Este estudo teve como objetivo investigar a associação entre sinais neurológicos, assim como possíveis fatores de risco e soroprevalência de Toxoplasma gondii e Neospora caninum em cães de Campo Grande, região de Mato Grosso do Sul, Brasil. Nesse estudo, os cães foram divididos em dois grupos, baseado na presença ou ausência de sinais neurológicos (n = 30 em cada grupo). O diagnóstico sorológico foi realizado por meio do teste imunofluorescência indireta (RIFI). No grupo com distúrbios neurológicos, 23.3% e 30% dos cães tinham anticorpos anti-T. gondii e anti-N. caninum, respectivamente. Além disso, três cães deste grupo estavam coinfectados com ambos os protozoários. No grupo sem sinais neurológicos, 16.7% e 13.3% dos cães foram soropositivos para T. gondii e N. caninum, respectivamente. Apesar da presença de sinais neurológicos não ter sido associado a infecção por T. gondii ou N. caninum ( P = 0.747 e P = 0.21, respectivamente), houve associação estatística entre soropositividade para T. gondii e alteração neurológica periférica (P = 0.016) entre os cães com sinais neurológicos. A ingestão de carne crua foi o único fator de risco que apresentou associação com a presença de anticorpos para N. caninum (P = 0.041). Estes resultados mostraram evidência de que a exposição a N. caninum e T. gondii em cães independe da presença de sinais neurológicos. Além disso, este estudo destaca a necessidade de investigação sorológica para T. gondii em cães com distúrbios neurológicos periféricos, e o oferecimento de carne crua aos animais deve ser evitada devido ao risco de infecção por neosporose.

https://doi.org/10.1590/0103-8478cr20220133

The Potentialities of Raman and XPS Techniques to Evaluate the Corrosion Products Formed on the 2198-T851 Aluminium Alloy Exposed to Sodium Chloride Solution
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Ferreira, M. O. A.

; Nascimento, J. P. L.

; Leite, N. B.

; Siervo, A. de

; Fernandes, G. L.

; Vaz, A. R.

; Gelamo, R. V.

; Aoki, I. V.

; Moreto, J. A.

Materials Research

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2023, Volume 26 elocation e20220453

Resumo: En | Texto: En | PDF: En

The aerospace industry is constantly looking for innovative materials that exhibit good mechanical and corrosion properties. The 2198-T851 (Al-Cu-Li) alloy was developed to replace the conventional Al-Cu-Mg in aircraft structures. Despite the usefulness of the 2198-T851 alloy, its performance may be affected when subjected to an aggressive medium containing chloride ions. The deposition of Nb2O5 coatings by using the reactive sputtering technique on the 2198-T851 alloy surface appears as a powerful tool to improve the corrosion resistance of this material. Recently, groundbreaking research findings have demonstrated the positive effect of Nb2O5 coatings on corrosion protection of alloy 2198-T851. However, the corrosion products originated from the 2198-T851 aluminium alloy are poorly understood. The use of Raman spectroscopy and XPS techniques may help to shed some light on the corrosion products of 2198-T851 alloy. Results demonstrated the corrosion products are mainly composed by CuCl2 x H2O, CuCl, Cu2Cl(OH)3, Al(OH)3, and AlO(OH).

https://doi.org/10.1590/1980-5373-mr-2022-0453

Biotransformed soybean cream as a new nutraceutical for skin care: collagen stimulation in vitro and ex vivo
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Leite, B.A.

; Bezerra, P.H.A.

; Stocco, B.

; Abichabki, N.

; Andrade, L.N.

; Fonseca, M.J.V.

; Torqueti, M.R.

Brazilian Journal of Medical and Biological Research

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2023, Volume 56 elocation e12781

Resumo: En | Texto: En | PDF: En

Treatments that attenuate the effects of hypoestrogenism in menopausal women have been gaining visibility. This study investigated the skin response to a phytoestrogen-enriched cosmetic formulation created by incorporating a biotransformed soybean extract (BE) into a cream-like matrix. Collagen-I expression was analyzed both in vitro (fibroblast cells) and ex vivo (skin explants). The results revealed an increased amount of collagen-I both in fibroblasts and human skin when treated with BE and BE-incorporated cream. Also, this collagen-I overexpression was inhibited by PHTPP, indicating a dependence on estrogen hormone receptor beta (ERβ) signaling. Moreover, BE was not harmful to skin microbiota, showing a promising nutricosmetic potential. Thus, this work presented a fully functional cream-like formulation that was shown to be safe and effectively increase collagen-I levels both in vitro and ex vivo.

https://doi.org/10.1590/1414-431x2023e12781

Arthropod fauna on the abaxial and adaxial surfaces of Acacia mangium (Fabaceae) leaves
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Gomes, G. N.

; Leite, G. L. D.

; Soares, M. A.

; Guanãbens, R. E. M.

; Lemes, P. G.

; Zanuncio, J. C.

Brazilian Journal of Biology

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2023, Volume 83 elocation e245536

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Resumo Acacia mangium (Willd., 1806) (Fabales: Fabaceae) é uma planta pioneira com rápido crescimento, rusticidade, potencial nitrificador e importante em programas de recuperação de áreas degradadas. O objetivo foi avaliar a distribuição e a diversidade funcional das interações e a dominância-K de grupos de artrópodes em árvores jovens de A. mangium. Os números de indivíduos de onze espécies de insetos fitófagos, três de abelhas e quatorze de inimigos naturais foram maiores na superfície adaxial de folhas dessa planta. A abundância, diversidade e riqueza de espécies de insetos fitófagos e inimigos naturais, e a abundância e riqueza de espécies de polinizadores foram maiores na face adaxial de folhas de A. mangium. A distribuição de cinco espécies de hemípteros sugadores de seiva e seis de formigas protocooperantes (Hymenoptera), com interação positiva entre esses grupos, e três de abelhas (Hymenoptera) foi agregada em folhas de plantas jovens de A. mangium. Aethalion reticulatum (L.) (Hemiptera: Aethalionidae) e Bemisia sp. (Hemiptera: Aleyrodidae); Brachymyrmex sp. e Camponotus sp. (Hymenoptera: Formicidae); e Trigona spinipes Fabricius (Hymenoptera: Apidae) foram os insetos fitófagos, inimigos naturais e polinizadores mais dominantes, respectivamente, em folhas de A. mangium. A definição da superfície foliar preferida pode auxiliar programas de manejo integrado de pragas.

Abstract Acacia mangium (Willd., 1806) (Fabales: Fabaceae) is a fast growing, rustic, pioneer species, with potential to fix nitrogen, and for programs to recover degraded areas. The objective was to evaluate the distribution and the functional diversity of interactions and the K-dominance of arthropod groups on A. mangium saplings. The number of individuals of eleven species of phytophagous insects, three bee species, and fourteen natural enemy species were highest on the adaxial leaf surface of this plant. Abundance, diversity and species richness of phytophagous insects and natural enemies, and abundance and species richness of pollinators were highest on the adaxial A. mangium leaf surface. The distribution of five species of sap-sucking hemipterans and six of protocooperating ants (Hymenoptera), with positive interaction between these groups, and three bee species (Hymenoptera) were aggregated on leaves of A. mangium saplings. Aethalion reticulatum (L.) (Hemiptera: Aethalionidae) and Bemisia sp. (Hemiptera: Aleyrodidae); Brachymyrmex sp. and Camponotus sp. (Hymenoptera: Formicidae); and Trigona spinipes Fabricius (Hymenoptera: Apidae) were the most dominant phytophagous insects, natural enemies, and pollinators, respectively, on A. mangium leaves. Knowledge of preferred leaf surfaces could help integrated pest management programs.

https://doi.org/10.1590/1519-6984.245536 100 downloads

Metabolomic and Histological Response of Passiflora cincinnata Infected with Cowpea aphid-borne mosaic virus (CABMV) Reveals Changes in Asymptomatic and Symptomatic Phases
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Mesquita, Paulo R. R.

; Barbosa, Naira C. S.

; Santos, Fábio N. dos

; Rodrigues, Frederico M.

; Abreu, Emanuel F. M.

; Leite, Kelly R. B.

; Jesus, Onildo N.

; Tumelero, Andréia I.

; Schnadelbach, Alessandra S.

; Barbosa, Cristiane J.

Journal of the Brazilian Chemical Society

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Dez 2022, Volume 33 Nº 12 Páginas 1456 - 1468

Resumo: En | Texto: En | PDF: En

Passion fruit woodiness disease, caused by the Cowpea aphid-borne mosaic virus (CABMV), is one of the leading phytosanitary challenges of passion fruit production. Passiflora cincinnata has been recognized for its potential in genetic improvement due to its highest resistance to CABMV and other phytopathogens. Metabolomic and histological alterations of P. cincinnata infected with CABMV were evaluated and searched for differential responses during the asymptomatic or symptomatic infection phases to correlate them with the mechanisms of metabolic defense. The metabolites of infected plants were analyzed by liquid chromatography-mass spectrometry. Based on the metabolomic profile, the times of infection were grouped into early or late infection phases. The metabolites related to CABMV infection were classified as alkaloids, saponins, phospholipids and acids. This study can assist agricultural institutions or farms in the early diagnosis and correct management of CABMV infection and contribute to the genetic improvement of the Passiflora genus against this disease.

https://doi.org/10.21577/0103-5053.20220080

Changes in the rest-activity rhythm in migraine patients are associated with anxiety symptoms
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David, Mírian C.M.M.

; Mattos, Marina S.B.

; Souto, Jandirlly J.S.

; Brito, Sarah A.C.F.

; Leite, Etcheverry S.

; Valença, Eduardo N.

; Galdino, Gilma S.

; Sampaio, Patrick G.G.

; Moura, Daniel M.C.

; Miguel, Mário A.L.

; Araújo, John F.

; Franco, Carlúcia I.F.

; Matos, Rhowena J.B.

Brazilian Journal of Psychiatry

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Dez 2022, Volume 44 Nº 6 Páginas 611 - 620

Resumo: En | Texto: En | PDF: En

Objective: To characterize rest-activity rhythm in chronic migraine (CM) and to investigate the relationship between this rhythm and depressive and anxiety symptoms in patients with CM. Methods: This was a study of adults aged 20 to 40 years. The rest-activity rhythm of patients with CM (n=23) and non-headache controls (NH, n=23) was assessed by actigraphy for 15 days, and they completed the following assessments: Visual Analogue Scale for pain intensity; Headache Diary; Headache Impact Test-6; Morningness-Eveningness Questionnaire; Pittsburgh Sleep Quality Index; Epworth Sleepiness Scale; Beck Depression Inventory; and State-Trait Anxiety Inventory. Results: Patients with CM showed less activity over 24 hours and more fragmented sleep. Reduced interdaily stability of the rest-activity rhythm was observed, with less robustness of this rhythm in the CM group. Multiple linear regressions revealed a significant association between the rest-activity rhythm and trait anxiety variables in patients with CM, specifically regarding the relative amplitude of the cycle, activity throughout 24 hours and during sleep, and robustness of the rest-activity rhythm. Conclusions: Our findings provide evidence that the robustness of the rest-activity rhythm, activity throughout 24 hours, and sleep fragmentation are associated with trait anxiety in patients with CM. Clinical trial registration: Brazilian Clinical Trials Registry (registration number: RBR-4M5J4S).

https://doi.org/10.47626/1516-4446-2021-2367

10.

Forage availability in Xaraés grass pastures subjected to nitrogen sources of the slow and fast release
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Matos, Luís Henrique Almeida

; Rodrigues, Carlindo Santos

; Pina, Douglas dos Santos

; Leite, Vagner Maximino

; Silva, Paula Aguiar

; Pereira, Taiala Cristina de Jesus

; Carvalho, Gleidson Giordano Pinto

Revista mexicana de ciencias pecuarias

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Set 2022, Volume 13 Nº 3 Páginas 706 - 724

Resumo: En Es | Texto: En Es | PDF: En | PDF: Es

Abstract The N-(n-butyl) thiophosphoric triamide (NBPT), a urease inhibitor, has been reported as one of the most promising compounds to reduce losses by volatilization, and to maximize the use of urea nitrogen (N) in agricultural systems. A field study was carried out to examine urease inhibitors' potential about volumetric density and forage mass grass (Brachiaria brizantha cv. Xaraés) to N application. The experiment was carried out from September 2017 to September 2018. The experimental design used was complete randomized blocks in the 3×2×4 factorial array, considering: three periods of the year (wet season, dry season, and the transition), two sources of urea (conventional urea and NBPT-treated urea), and four N rates (0, 80, 160 and 240 kg N ha-1 yr-1), replicated three times. Nitrogen sources promoted a positive effect (P<0.0001) on bulk density, forage mass, and in the grazing stratum during the wet season and the transition season, with increasing N rates in pastures. The leaf: stem ratio decreased linearly (P<0.0045) as increased N rates, and the higher ratio during the wet season and lower in the dry season of the year. For the rates of 80 kg N ha-1 yr-1, there was a significant difference (P=0.0042) between sources, with greater (P=0.0006) forage mass of 0-30 cm, post-grazing forage mass (P=0.0042) and forage volumetric density (P=0.0006), when utilized the conventional urea. The application of N, regardless of the source, provides an increase in forage mass and volumetric density in Xaraés grass pastures up to a dose of 240 kg N ha-1 yr-1, in the transition season and wet season.

Resumen La N-(n-butil) triamida tiofosfórica (NBPT) es un inhibidor de la ureasa usado en los sistemas agrícolas para reducir las pérdidas por volatilización de NH3 y maximizar el uso del nitrógeno ureico (N). Se realizó un estudio de campo para evaluar el efecto de la urea tratada con NBPT sobre la densidad volumétrica y la masa de forraje en el pasto Brachiaria brizantha cv. Xaraés. El periodo experimental fue de un año (septiembre 2017 a septiembre 2018). El diseño experimental fue de bloques completamente aleatorios con un arreglo factorial de 3×2×4: tres estaciones del año (lluvia, sequía y transición), dos fuentes de urea (convencional y tratada con NBPT), y cuatro tasas de N (0, 80, 160 y 240 kg N ha-1 año-1). Se hicieron tres réplicas. Ambas fuentes de nitrógeno tuvieron un efecto positivo (P<0.0001) sobre la densidad aparente, la masa de forraje y el estrato de pastoreo durante la estación de lluvia y la de transición. También produjeron aumentos de N en los pastos. La relación hoja:tallo disminuyó linealmente (P<0.0045) a medida que aumentaron las tasas de N; la relación mayor fue durante la estación de lluvia y la menor en la estación de sequía. A la tasa de 80 kg N ha-1 año-1, hubo una diferencia (P=0.0042) entre las fuentes de N. A esta tasa la urea convencional produjo una mayor (P=0.0006) masa de forraje total, masa de forraje pospastoreo (P= 0.0042) y densidad volumétrica del forraje (P=0.0006). En las estaciones de lluvia y de transición, la aplicación de N, cual sea la fuente, resultó en un aumento en la masa y la densidad volumétrica del forraje en praderas de pasto Xaraés hasta la tasa de 240 kg N ha-1 año-1.

https://doi.org/10.22319/rmcp.v13i3.6022 9 downloads

11.

Gas exchange and growth of peanut crop subjected to saline and water stress
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Barbosa, Andreza S.

; Sousa, Geocleber G. de

; Freire, Márcio H. da C.

; Leite, Kelly N.

; Silva, Fred D. B. da

; Viana, Thales V. de A.

Revista Brasileira de Engenharia Agrícola e Ambiental

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Ago 2022, Volume 26 Nº 8 Páginas 557 - 563

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

RESUMO A cultura do amendoim apresenta grande interesse econômico, em decorrência de suas sementes, constituírem importante fonte de proteína vegetal e de óleo comestível. O objetivo do presente trabalho foi avaliar a fisiologia e crescimento da cultura do amendoim submetido a estresse salino e hídrico. O experimento foi conduzido em Auroras, Redenção, Ceará, Brasil. O delineamento experimental foi inteiramente casualizado em parcelas subdivididas, cujas parcelas referem-se aos níveis de condutividade elétrica da água de irrigação - CEa (1,0; 2,0; 3,0; 4,0 e 5,0 dS m-1) e as subparcelas aos regimes hídricos de 50 e 100% da evapotranspiração da cultura. O estresse salino afeta negativamente a altura de planta, número de folhas e massa seca da parte aérea, índices relativos de clorofila, transpiração e a temperatura foliar da cultura do amendoim. O regime hídrico de 100% da ETc proporcionou maiores desempenhos para as variáveis diâmetro do caule, número de folhas e massa seca da parte aérea da cultura do amendoim.

ABSTRACT Peanut crops are of great economic interest because their seeds are used as an important source of vegetable protein and edible oil. The objective of this study was to evaluate the physiological indices and growth of peanut crops subjected to saline and water stress. The experiment was conducted in Auroras, Redenção, Ceará, Brazil using a completely randomized split plot statistical design. The plots were composed of irrigation water treatments with varying levels of electrical conductivity - ECw (1.0, 2.0, 3.0, 4.0 and 5.0 dS m-1), while the subplots were formed by the water regimes of 50% and 100% crop evapotranspiration. Plant height, leaf number, shoot dry matter, relative chlorophyll level, transpiration, and leaf temperature were affected by salt stress. The water regime of 100% ETc provided better performance for the variables stem diameter, leaf number, and shoot dry mass of peanuts.

https://doi.org/10.1590/1807-1929/agriambi.v26n8p557-563

12.

Mathematical modeling and thermodynamic properties in the drying of citron watermelon seeds
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Leite, Daniela D. de F.

; Queiroz, Alexandre J. de M.

; Figueirêdo, Rossana M. F. de

; Santos, Francislaine S. dos

; Silva, Semirames do N.

; Santos, Dyego da C.

Revista Brasileira de Engenharia Agrícola e Ambiental

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Jan 2022, Volume 26 Nº 1 Páginas 67 - 74

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

RESUMO A melancia africana é um produto agrícola de excelente potencial econômico. Suas sementes são muito utilizadas para extração de óleo, servindo como fonte energética, demonstrando características nutricionais que a habilitam como produto a ser estudado. Assim, objetivou-se caracterizar quanto à composição físico-química, as sementes de melancia africana, além de determinar a cinética de secagem, ajustar modelos matemáticos aos dados, determinar os coeficientes de difusividade efetiva e propriedades termodinâmicas. As sementes foram submetidas à secagem em secador convectivo, variando-se a temperatura de secagem, com velocidade do ar de 1,0 m s-1. Com o aumento da temperatura de secagem diminuiu o teor de água, atividade de água, teor de cinzas, acidez total titulável, lipídios e açúcar redutor. As sementes de melancia africana são ricas em lipídios e cinzas, tem baixos teores de açúcares e baixa acidez; as cinéticas de secagem foram muito bem descritas pelos modelos Dois Termos e Aproximação da Difusão, seguidos pelos modelos de Midilli e Page, que resultaram em ajustes aceitáveis. A difusividade efetiva acompanhou o aumento da temperatura de secagem, e este comportamento foi satisfatoriamente ajustado por equação do tipo Arrhenius. As variações de entalpia e entropia foram reduzidas com a temperatura de secagem, com aumentos da energia livre de Gibbs.

ABSTRACT Citron watermelon is an agricultural product of excellent economic potential. Its seeds are widely used for oil extraction, serving as an energy source, showing nutritional characteristics that make them a suitable product to be studied. Thus, the objective was to characterize citron watermelon seeds regarding their physicochemical composition, in addition to determining drying kinetics, fitting mathematical models to the data, and determining the effective diffusivity coefficients and thermodynamic properties. The seeds were dried in a convective dryer, varying the drying temperature, with air velocity of 1.0 m s-1. With the increase in drying temperature, there were reductions in moisture content, water activity (aw), ash concentration, total titratable acidity, lipids and reducing sugar. Citron watermelon seeds are rich in lipids and ash, have low sugar concentration and low acidity; their drying kinetics was very well described by the Two Terms and Approximation of Diffusion models, followed by the models of Midilli and Page, which resulted in acceptable fits. Effective diffusivity accompanied the increase in drying temperature, and this behavior was well fitted by an Arrhenius-type equation. Enthalpy and entropy variations were reduced with drying temperature, with increments in Gibbs free energy.

https://doi.org/10.1590/1807-1929/agriambi.v26n1p67-74 76 downloads

13.

A GAMLSS approach to predicting growth of Nopalea cochenillifera Giant Sweet clone submitted to water and saline stress
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Costa, Álefe Chagas de Lima

; Oliveira, Antonio Dennys Melo de

; Caraciolo, João Pedro Soares

; Lucena, Leandro Ricardo Rodrigues de

; Leite, Maurício Luiz de Mello Vieira

Acta Scientiarum. Agronomy

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2022, Volume 44 elocation e54939

Resumo: En | Texto: En | PDF: En

ABSTRACT. Water and saline stresses are the main factors affecting agricultural production in semiarid regions. The tolerance of forage cactus to water and salt deficit makes it a promising solution, in particular Nopalea cochenillifera. The growth curves for species facing these conditions can provide useful information supporting the cultivation and management of natural populations and carry significant biological importance as growth rate assessment contributes to maintaining species viability. The objective of this study was to estimate the plant height and linear dimensions (length, width, and thickness) of N. cochenillifera Giant Sweet clone growing under water and saline stress. The experiment design was completely randomized, comprising a 4 × 4 factorial, with four water and four salinity levels; there were four replications. In order to estimate plant height in N. cochenillifera Giant Sweet clone as a function of the accumulated thermal sum, generalized additive models for location, scale, and shape (GAMLSS) were used to determine water level, saline level, length, width, and thickness. We constructed models using four distributions: the Weibull, Gumbel, Logistic, and Box-Cox power exponential distributions. The models were evaluated using global deviation and the generalized Akaike criterion. The Box-Cox power exponential proved to be the most effective in estimating N. cochenillifera height. This model enabled information relevant to practical environmental management to be obtained, as it precisely defined the optimum salt application and the required amount of replacement water, together with the cladode width for each plant growth stage using the accumulated thermal sum.

https://doi.org/10.4025/actasciagron.v44i1.54939

14.

Initial growth of forage cactus clones at different potassium fertilization levels
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Cirino Junior, Baltazar

; Leite, Maurício Luiz de Mello Vieira

; Silva, Fábio Eráclito da

; Alves, Cleber Pereira

; Oliveira, Alexandre Campelo de

; Eugênio, Danielle da Silva

Ciência Animal Brasileira

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2022, Volume 23 elocation e70836

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Resumo Objetivou-se avaliar o efeito de diferentes níveis de adubação potássica no crescimento inicial de clones de palma forrageira (Nopalea cochenillifera Salm Dyck). O experimento foi conduzido durante seis meses, disposto em delineamento em blocos ao acaso, em esquema fatorial 5x2, sendo cinco níveis de adubação potássica (0, 250, 500, 750 e 1000 Kg de K2O ha-1) e dois clones de palma forrageira (Doce Gigante e Doce Miúda), com quatro repetições. Foi plantado um cladódio por vaso (unidade experimental) com capacidade para 7 kg de solo (24 x 17 x 23 cm). Ao longo do período experimental, foram avaliadas as características estruturais das plantas, tais como altura e largura de planta, comprimento, largura, espessura e perímetro de cladódio, bem como contabilização do número de cladódios total e por ordem de surgimento. Ao final do experimento avaliou-se a biomassa, para determinação do rendimento de massa fresca (MV) e seca (MS) da parte aérea e do sistema radicular. Após a determinação de MS, determinou-se o teor potássico nos tecidos vegetais. Os dados foram submetidos a ANOVA e, caso necessário, ao teste de Tukey a 5% de significância. A adubação potássica e os clones de palma forrageira não exerceram influências significativas nas variáveis avaliadas durante a condução experimental. A adubação potássica não influencia as características estruturais, produtivas e teor potássico no crescimento inicial de clones de Nopalea cochenillifera.

Abstract The objective was to evaluate the effect of different levels of potassium fertilization on the initial growth of forage cactus (Nopalea cochenillifera Salm Dyck) clones. The experiment lasted six months, arranged in a randomized block design, in a 5 x 2 factorial scheme, with five levels of potassium fertilization (0, 250, 500, 750, and 1,000 kg of K2O ha-1) and two forage cactus clones (Little Sweet and Giant Sweet), with four replicates. One cladode was planted per pot (experimental unit) with a capacity of 7 kg of soil (24 x 17 x 23 cm). During the experimental period, the plants' structural characteristics were evaluated, such as plant height and width, length, width, thickness, and perimeter of the cladode, as well as accounting for the number of total cladodes, and in order of appearance. At the end of the experiment, biomass was evaluated to determine the fresh matter (FM) and dry matter (DM) yield of the aerial part and the root system. After determining the DM, the potassium content in the plant tissues was determined. The data were submitted to ANOVA and, if necessary, to the Tukey test at a 5% significance level. The potassium fertilization and the forage palm clones did not exert influences based on the variables evaluated during the experimental conduction. Potassium fertilization does not influence the structural and productive characteristics and the potassium content in the N. cochenillifera clones' initial growth.

https://doi.org/10.1590/1809-6891v22e-70836e

15.

In vitro toxicity of Niedenzuella (Tetrapterys) multiglandulosa on bovine embryos
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Bull, Valquíria

; Leite, Ana Carolina

; Botelho, Ana Flávia Machado

; Silva, Rayanne Henrique Santana da

; Silva, Eliane Beatriz Magalhães

; Soto-Blanco, Benito

; Nepomuceno, Anelise de Carvalho

; Borges, Álan Maia

; Melo, Marília Martins

Ciência Animal Brasileira

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2022, Volume 23 elocation e71762

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Resumo Niedenzuella (Tetrapterys) multiglandulosa, uma videira encontrada no Brasil, tem sido correlacionada a surtos de intoxicações em bovinos e búfalos, gerando perdas econômicas relacionadas à morte por insuficiência cardíaca, aborto, natimorto e mortalidade neonatal. O objetivo deste estudo foi examinar o potencial embriotóxico do extrato vegetal aquoso em embriões bovinos in vitro. O estudo in vitro foi realizado em cinco repetições de cultura de embriões bovinos distribuídos em dois grupos: controle, meio de cultura de embriões in vitro sem o extrato aquoso da planta; grupo tratado, com adição de 2,7mg / mL de extrato vegetal aquoso (10%) à cultura do embrião no sexto dia de cultivo. A taxa de clivagem foi avaliada no dia 2 da cultura de células. Viabilidade, eclodibilidade e subdesenvolvimento de blastocistos no sétimo, oitavo e nono dia (D7, D8 e D9, respectivamente) de cultura foram avaliados em microscópio estereoscópico. No dia 7, os blastocistos foram submetidos ao ensaio TUNEL para determinar o índice apoptótico. Observamos redução significativa da produção de blastocisto / número de embriões clivados (60,6% vs 41,5%); redução da produção de blastocistos / número total de oócitos bovinos maturados (35,1% vs 21,3%); e taxas de eclosão embrionária (38,0% vs 10,0%). No entanto, nenhum efeito foi observado na taxa de apoptose. Em conclusão, o extrato aquoso das folhas de N. multiglandulosa reduz a viabilidade do embrião bovino in vitro, sugerindo possíveis efeitos prejudiciais no desenvolvimento embrionário.

Abstract Niedenzuella (Tetrapterys) multiglandulosa, a vine plant found in Brazil, has been correlated to outbreaks of poisoning in cattle and buffaloes, generating economic losses related to the death due to heart failure, miscarriage, abortion, stillbirth, and neonatal mortality. The aim of this study was to examine the embryotoxic potential of the aqueous plant extract on in vitro bovine embryos. In vitro study was performed in five replicates of bovine embryo culture assigned in two groups: control, in vitro embryo culture medium without the aqueous plant extract; treated group, with addition of 2.7mg/mL of aqueous plant extract (10%) to the embryo culture on the sixth day of culture. Cleavage rate was evaluated at day 2 of the cell culture. Viability, hatchability and underdevelopment of blastocysts on the seventh, eighth, and ninth days (D7, D8, and D9, respectively) of culture were assessed under stereoscopic microscope. On day 7, blastocysts were submitted to TUNEL assay to determine apoptotic index. In vitro exposure of bovine embryos to of N. multiglandulosa resulted in reduced embryo development and survival, evaluated by dark cytoplasm indicating poor morphology and poor quality with marked reduction of hatchability. We observed a significant reduction of blastocyst production/number of cleaved embryos (60.6% vs 41.5%); reduction of blastocysts production/total number of matured bovine oocytes (35.1% vs 21.3%); and embryonic hatching rates (38.0% vs 10.0%). However, no effects were observed on the apoptotic rate. In conclusion, aqueous extract of N. multiglandulosa leaves reduces bovine embryo viability in vitro, suggesting possible detrimental effects on embryo development.

https://doi.org/10.1590/1809-6891v23e-71762e

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