Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 481
Filtrar
1.
Eur Arch Paediatr Dent ; 25(5): 715-720, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39266902

RESUMEN

AIM: To investigate the association between presence of caries in anterior teeth and bullying victimization in schoolchildren. METHODS: A cross-sectional study was conducted in Brazil with a sample of 387 schoolchildren aged 6 to 10 years. The presence of moderate/extensive dental caries was assessed using the International System for the Evaluation and Detection of Dental Caries (ICDAS-II). The children answered the "Olweus Bullying" (QBO). Descriptive analyses were performed, and the associations between bullying victimization and independent variables collected were determined by univariate and multivariate Poisson regression. RESULTS: The prevalence of bullying victimization was 66.4%. Bullying victimization was higher among children who had moderate/extensive caries in some anterior teeth (p = 0.010). 8-year-old (p = 0.048), 9-year-old (p = 0.001), and 10-year-old (p = 0.002) children reported greater bullying victimization when compared to 6-year-olds. CONCLUSION: The presence of moderate/extensive dental caries in anterior teeth is associated with bullying victimization in schoolchildren.


Asunto(s)
Acoso Escolar , Caries Dental , Humanos , Niño , Estudios Transversales , Brasil/epidemiología , Caries Dental/epidemiología , Masculino , Femenino , Acoso Escolar/estadística & datos numéricos , Víctimas de Crimen/estadística & datos numéricos , Prevalencia
4.
Braz. j. biol ; 84: e261972, 2024. tab, graf, mapas
Artículo en Inglés | VETINDEX | ID: biblio-1384099

RESUMEN

At the global level, Sorghum bicolor (L.), is one of the most important crops, which ranks fifth among all cereals. It is cultivated in Africa, Asia, Oceania and the Americas, where it serves as a source of food and feed for humans and animals, respectively. However, production is constrained by several factors including pests and diseases. Among the pests that are known to attack Sorghum, Schizaphis graminum (Rondani), commonly called the green cereal aphid, is the most destructive pest of sorghum. S. graminum damage to sorghum is worsen by water deficit which favors its occurrence. Limited information on the spatial distribution of the pest and its natural enemies impedes the development of ecologically friendly management strategies. Therefore, the objective of this research was to determine the spatiotemporal distribution of S. graminum and its natural enemy Coccinella septempunctata (L.) during the vegetative and reproductive stage of the crop using geostatistical analysis. The spatiotemporal distribution of S. graminum was influenced by Sorghum development stage, surrounding landscape, and presence of its main predator C. septempunctata. Moreover, the abundance of C. septempunctata was influenced by the density of S. graminum. The findings from this study are required for developing sustainable pest management strategies against S. graminum.


Em uma escala global o Sorghum bicolor (L.) é uma das culturas mais importantes, ocupando o quinto lugar entre todos os cereais. É cultivada na África, Ásia, Oceania e Américas, onde serve como fonte de alimento e ração para humanos e animais, respectivamente. No entanto, a produção é limitada por vários fatores, incluindo pragas e doenças. Entre as pragas que atacam o sorgo, Schizaphis graminum (Rondani), comumente chamado de pulgão verde dos cereais, é a praga mais destrutiva do sorgo. O dano de S. graminum ao sorgo é agravado pelo déficit hídrico que favorece sua ocorrência. Informações limitadas sobre a distribuição espacial da praga e seus inimigos naturais impedem o desenvolvimento de estratégias de manejo ecologicamente corretas. Portanto, o objetivo desta pesquisa foi determinar a distribuição espaço-temporal de S. graminum e seu inimigo natural Coccinella septempunctata (L.) durante a fase vegetativa e reprodutiva da cultura por meio de análise geoestatística. A distribuição espaço-temporal de S. graminum foi influenciada pelo estágio de desenvolvimento do sorgo, paisagem circundante e presença de seu principal predador C. septempunctata. Além disso, a abundância de C. septempunctata foi influenciada pela densidade de S. graminum. Os resultados deste estudo são necessários para o desenvolvimento de estratégias sustentáveis de manejo de pragas contra S. graminum.


Asunto(s)
Animales , Áfidos/crecimiento & desarrollo , Coccinella septempunctata , Control de Plagas , Sorghum/parasitología
5.
Braz. j. biol ; 84: e257975, 2024. ilus
Artículo en Inglés | VETINDEX | ID: biblio-1374668

RESUMEN

Galling insects are abundant in nature, found in many ecosystems globally, with species attacking plants of economic importance. We studied the effects of free-feeding organisms on the abundance of galling insects on Caryocar brasiliense (Caryocaraceae) trees in the Brazilian Cerrado (Savanna). Percentage of defoliation and the number of phytophagous mites or number of phytophagous Hemiptera correlated negatively with percentage of galled leaves and the parasitoid Eurytoma sp. (Hymenoptera: Eurytomidae) adults, respectively. Percentage of galled leaves and the numbers of Eurytoma sp. adults and phytophagous mites correlated positively with spiders. Numbers of mites and Hemiptera phytophagous correlated positively with those of lady beetles and Sycophila sp. (Hymenoptera: Eurytomidae), respectively. The number of Ablerus magistretti Blanchard (Hymenoptera: Aphelinidae) adults correlated negatively with Sycophila sp. The number of Agistemus sp. (Acari: Stigmaeidae) correlated, negatively and positively, with those of lady beetles and phytophagous mites, respectively. Free-feeding herbivores affected the presence of galling insects (Hymenoptera) on C. brasiliense trees, competing for food and space. The same was observed between two parasitoids of Eurytoma sp. galling insect, which can reduce the natural biological control of this pest.


Insetos galhadores são abundantes na natureza, encontrados em muitos ecossistemas globalmente, com espécies atacando plantas de importância econômica. Os efeitos de herbívoros de alimentação livre na abundância de insetos galhadores em árvores de Caryocar brasiliense (Caryocaraceae) no Cerrado brasileiro (Savana) foram estudados. A porcentagem de desfolha e o número de ácaros fitófagos ou de Hemiptera fitófagos correlacionaram-se, negativamente, com a percentagem de folhas galhadas e de adultos do parasitoide Eurytoma sp. (Hymenoptera: Eurytomidae), respectivamente. Porcentagem de folhas galhadas e o número de Eurytoma sp. adultos e ácaros fitófagos correlacionaram-se, positivamente, com o de aranhas. Os números de ácaros e fitófagos Hemiptera correlacionaram-se, positivamente, com os de joaninhas e Sycophila sp. (Hymenoptera: Eurytomidae), respectivamente. O número de adultos de Ablerus magistretti Blanchard (Hymenoptera: Aphelinidae) correlacionou-se, negativamente, com Sycophila sp. O número de Agistemus sp. (Acari: Stigmaeidae) correlacionou-se, negativa e positivamente, com os de joaninhas e ácaros fitófagos, respectivamente. Herbívoros de alimentação livre afetaram a presença de insetos galhadores (Hymenoptera) em árvores de C. brasiliense, competindo por alimento e espaço. O mesmo foi observado entre dois parasitoides de Eurytoma sp., o que pode reduzir o controle biológico natural dessa praga.


Asunto(s)
Animales , Arañas , Árboles , Control Biológico de Vectores , Insectos , Ácaros , Brasil , Pradera
10.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469246

RESUMEN

Abstract Worldwide, conventional agriculture makes extensive use of pesticides. Although the effects of herbicides are relatively well known in terms of environmental impacts on non-target organisms, there is very little scientific evidence regarding the impacts of herbicide residues on aquatic arthropods from tropical conservation areas. This study evaluates for the first time the toxicity of the herbicides ametryn, atrazine, and clomazone on the aquatic insect Limnocoris submontandoni (Hemiptera: Naucoridae). The lethal concentration (LC50) of herbicides was evaluated for these insects, as well as the effect of the herbicides on the insects tissues and testicles. The estimated LC50 was 1012.41, 192.42, and 46.09 mg/L for clomazone, atrazine, and ametryn, respectively. Spermatocyte and spermatid changes were observed under the effect of atrazine, and effects on spermatogenesis were observed for some concentrations of clomazone, with apparent recovery after a short time. Our results provide useful information on the effects of herbicide residues in aquatic systems. This information can help minimize the risk of long-term reproductive effects in non-target species that have been previously overlooked in ecotoxicology studies.


Resumo Em todo o mundo, a agricultura convencional faz uso extensivo de pesticidas. Embora os efeitos dos herbicidas sejam relativamente bem conhecidos em termos de impactos ambientais em organismos não-alvo, há pouca evidência científica sobre os impactos de resíduos de herbicidas em artrópodes aquáticos de áreas de conservação tropicais. Este estudo avalia pela primeira vez a toxicidade dos herbicidas ametryn, atrazine e clomazone sobre o inseto aquático Limnocoris submontandoni (Hemiptera: Naucoridae). A concentração letal (LC50) de herbicidas foi avaliada para esses insetos, bem como o efeito dos herbicidas nos tecidos e testículos dos insetos. A LC50 estimada foi de 1012,41, 192,42 e 46,09 mg/L para clomazone, atrazine e ametryn, respectivamente. Alterações nos espermatócitos e espermátides foram observadas sob o efeito de atrazine, e efeitos na espermatogênese foram observados para algumas concentrações de clomazone, com aparente recuperação após um curto período de tempo. Nossos resultados fornecem informações úteis sobre os efeitos de resíduos de herbicidas em sistemas aquáticos. Essas informações podem ajudar a minimizar o risco de efeitos reprodutivos de longo prazo em espécies não-alvo que foram negligenciadas anteriormente em estudos de ecotoxicologia.

11.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469259

RESUMEN

Abstract Acacia mangium is a pioneer species with fast growth and frequently used in the recovery of degraded areas. The objectives were to evaluate insects and spiders, their ecological indices and interactions on A. mangium saplings in a tropical degraded area in recovering process. The experimental design was completely randomized with 24 replications, with treatments represented by the first and second years after A. mangium seedling planted. Numbers of leaves/branch, branches/sapling, and ground cover by A. mangium saplings, Hemiptera: Phenacoccus sp. and Pachycoris torridus; Hymenoptera: Tetragonisca angustula and Trigona spinipes, Brachymyrmex sp., Camponotus sp. and Cephalotes sp.; Blattodea: Nasutitermes sp. and Neuroptera: Chrysoperla sp.; abundance, species richness of pollinating insects, tending ants, and the abundance of Sternorrhyncha predators were greatest in the second year after planting. Numbers of Hemiptera: Aethalium reticulatum, Hymenoptera: Camponotus sp., Cephalotes sp., Polybia sp., T. angustula, T. spinipes, tending ants, pollinating insects, Sternorrhyncha predators and species richness of tending ants were highest on A. mangium saplings with greatest numbers of leaves or branches. The increase in the population of arthropods with ground cover by A. mangium saplings age increase indicates the positive impact by this plant on the recovery process of degraded areas.


Resumo Acacia mangium é uma espécie pioneira, de rápido crescimento e utilizada na recuperação de áreas degradadas. Os objetivos foram avaliar insetos e aranhas, seus índices ecológicos e interações com plantas de A. mangium em área tropical degradada em processo de recuperação. O delineamento experimental foi inteiramente casualizado com 24 repetições, com os tratamentos representados pelos primeiro e segundo anos após a plantio de A. mangium. Os números de folhas/galhos, galhos/plantas e cobertura do solo por plantas de A. mangium, de Hemiptera: Phenacoccus sp. e Pachycoris torridus; Hymenoptera: Tetragonisca angustula e Trigona spinipes, Brachymyrmex sp., Camponotus sp. e Cephalotes sp.; Blattodea: Nasutitermes sp. e Neuroptera: Chrysoperla sp.; a abundância, riqueza de espécies de insetos polinizadores, formigas cuidadoras e a abundância de predadores de Sternorrhyncha foram maiores no segundo ano após o plantio. Os números de Hemiptera: Aethalium reticulatum, Hymenoptera: Camponotus sp., Cephalotes sp., Polybia sp., T. angustula, T. spinipes, formigas cuidadoras, insetos polinizadores, predadores de Sternorrhyncha e a riqueza de espécies de formigas cuidadoras foram maiores em plantas de A. mangium com maior altura e número de folhas ou galhos. O aumento populacional de artrópodes e da cobertura do solo com o processo de envelhecimento das plantas de A. mangium indicam impacto positivo dessa planta na recuperação de áreas degradadas.

15.
Braz. j. biol ; 84: e252088, 2024. tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1345543

RESUMEN

Abstract Acacia mangium is a pioneer species with fast growth and frequently used in the recovery of degraded areas. The objectives were to evaluate insects and spiders, their ecological indices and interactions on A. mangium saplings in a tropical degraded area in recovering process. The experimental design was completely randomized with 24 replications, with treatments represented by the first and second years after A. mangium seedling planted. Numbers of leaves/branch, branches/sapling, and ground cover by A. mangium saplings, Hemiptera: Phenacoccus sp. and Pachycoris torridus; Hymenoptera: Tetragonisca angustula and Trigona spinipes, Brachymyrmex sp., Camponotus sp. and Cephalotes sp.; Blattodea: Nasutitermes sp. and Neuroptera: Chrysoperla sp.; abundance, species richness of pollinating insects, tending ants, and the abundance of Sternorrhyncha predators were greatest in the second year after planting. Numbers of Hemiptera: Aethalium reticulatum, Hymenoptera: Camponotus sp., Cephalotes sp., Polybia sp., T. angustula, T. spinipes, tending ants, pollinating insects, Sternorrhyncha predators and species richness of tending ants were highest on A. mangium saplings with greatest numbers of leaves or branches. The increase in the population of arthropods with ground cover by A. mangium saplings age increase indicates the positive impact by this plant on the recovery process of degraded areas.


Resumo Acacia mangium é uma espécie pioneira, de rápido crescimento e utilizada na recuperação de áreas degradadas. Os objetivos foram avaliar insetos e aranhas, seus índices ecológicos e interações com plantas de A. mangium em área tropical degradada em processo de recuperação. O delineamento experimental foi inteiramente casualizado com 24 repetições, com os tratamentos representados pelos primeiro e segundo anos após a plantio de A. mangium. Os números de folhas/galhos, galhos/plantas e cobertura do solo por plantas de A. mangium, de Hemiptera: Phenacoccus sp. e Pachycoris torridus; Hymenoptera: Tetragonisca angustula e Trigona spinipes, Brachymyrmex sp., Camponotus sp. e Cephalotes sp.; Blattodea: Nasutitermes sp. e Neuroptera: Chrysoperla sp.; a abundância, riqueza de espécies de insetos polinizadores, formigas cuidadoras e a abundância de predadores de Sternorrhyncha foram maiores no segundo ano após o plantio. Os números de Hemiptera: Aethalium reticulatum, Hymenoptera: Camponotus sp., Cephalotes sp., Polybia sp., T. angustula, T. spinipes, formigas cuidadoras, insetos polinizadores, predadores de Sternorrhyncha e a riqueza de espécies de formigas cuidadoras foram maiores em plantas de A. mangium com maior altura e número de folhas ou galhos. O aumento populacional de artrópodes e da cobertura do solo com o processo de envelhecimento das plantas de A. mangium indicam impacto positivo dessa planta na recuperação de áreas degradadas.


Asunto(s)
Animales , Arañas , Acacia , Insectos , Biomarcadores Ambientales , Restauración y Remediación Ambiental
17.
Braz. j. biol ; 84: e247487, 2024. graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1345555

RESUMEN

Abstract Worldwide, conventional agriculture makes extensive use of pesticides. Although the effects of herbicides are relatively well known in terms of environmental impacts on non-target organisms, there is very little scientific evidence regarding the impacts of herbicide residues on aquatic arthropods from tropical conservation areas. This study evaluates for the first time the toxicity of the herbicides ametryn, atrazine, and clomazone on the aquatic insect Limnocoris submontandoni (Hemiptera: Naucoridae). The lethal concentration (LC50) of herbicides was evaluated for these insects, as well as the effect of the herbicides on the insects' tissues and testicles. The estimated LC50 was 1012.41, 192.42, and 46.09 mg/L for clomazone, atrazine, and ametryn, respectively. Spermatocyte and spermatid changes were observed under the effect of atrazine, and effects on spermatogenesis were observed for some concentrations of clomazone, with apparent recovery after a short time. Our results provide useful information on the effects of herbicide residues in aquatic systems. This information can help minimize the risk of long-term reproductive effects in non-target species that have been previously overlooked in ecotoxicology studies.


Resumo Em todo o mundo, a agricultura convencional faz uso extensivo de pesticidas. Embora os efeitos dos herbicidas sejam relativamente bem conhecidos em termos de impactos ambientais em organismos não-alvo, há pouca evidência científica sobre os impactos de resíduos de herbicidas em artrópodes aquáticos de áreas de conservação tropicais. Este estudo avalia pela primeira vez a toxicidade dos herbicidas ametryn, atrazine e clomazone sobre o inseto aquático Limnocoris submontandoni (Hemiptera: Naucoridae). A concentração letal (LC50) de herbicidas foi avaliada para esses insetos, bem como o efeito dos herbicidas nos tecidos e testículos dos insetos. A LC50 estimada foi de 1012,41, 192,42 e 46,09 mg/L para clomazone, atrazine e ametryn, respectivamente. Alterações nos espermatócitos e espermátides foram observadas sob o efeito de atrazine, e efeitos na espermatogênese foram observados para algumas concentrações de clomazone, com aparente recuperação após um curto período de tempo. Nossos resultados fornecem informações úteis sobre os efeitos de resíduos de herbicidas em sistemas aquáticos. Essas informações podem ajudar a minimizar o risco de efeitos reprodutivos de longo prazo em espécies não-alvo que foram negligenciadas anteriormente em estudos de ecotoxicologia.


Asunto(s)
Animales , Artrópodos , Contaminantes Químicos del Agua/toxicidad , Hemípteros , Herbicidas/toxicidad , Ecotoxicología , Genitales
18.
Braz J Biol ; 83: e275824, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37970906

RESUMEN

Schistosomiasis, caused by Schistosoma mansoni Sambon, 1907, is a severe and widely distributed parasitic disease, affecting about 200 million people worldwide. The disease is recognized by elevated mortality rates, especially among those living in areas of poor sanitation. Currently, the chemotherapeutic treatment is solely based on using the praziquantel drug. Therefore, there is a need for the discovery of new medicines for the treatment of this parasitosis. Thus, this work aimed to evaluate the schistosomicidal activity of ethanolic crude extracts from the branches, leaves, flowers, and fruits of Handroanthus impetiginosus (Mart ex DC.) Masttos and characterize its metabolic profile by UPLC-ESI-QTOF analysis. Evaluation of plant extract on S. mansoni was carried out in adult worms in vitro, in which the mortality rate was quantified, and the damages in the tegument of the worms were monitored. All extracts induced changes in the viability of adult males of S. mansoni, causing the death of the parasites, which was directly dependent of the concentration.


Asunto(s)
Bignoniaceae , Esquistosomicidas , Tabebuia , Humanos , Masculino , Esquistosomicidas/farmacología , Esquistosomicidas/uso terapéutico , Frutas , Etanol , Flores , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico
19.
Artículo en Inglés | MEDLINE | ID: mdl-37442311

RESUMEN

Atmospheric particulate matter (APM) produced by the steel industry comprises a complex mixture of particles that includes a wide variety of metals and metallic nanoparticles. These particles settle out onto areas surrounding the industries. There is evidence that this 'settleable' APM (SePM) may cause air-to-water cross-contamination with significant effects on aquatic biota. Recent investigations have reported sublethal impacts on the gill structure and blood oxygen-carrying capacity of fishes, which raises the hypothesis that there will be consequences for gas exchange capacity and ability to support aerobic activities. Therefore, we investigated the effects of an environmentally relevant level of SePM contamination on swimming performance and associated aerobic metabolic rates in Nile tilapia, Oreochromis niloticus. Short-term exposure (96 h) to SePM reduced critical swimming speed, energetic efficiency of aerobic swimming, standard metabolic rate, maximum metabolic rate, and aerobic scope. The compromised swimming performance could have adverse ecological effects by limiting foraging ability, predator evasion, territorial protection, and migration. The impairments to aerobic capacity could also affect overall fish performance by influencing long-term energy balance and allocation to growth and reproduction. Thus, despite being sublethal, SePM contamination is considerably debilitating, and if its limiting effects are not compensated for in the longer term, this may reduce the survival and fitness of fish populations.


Asunto(s)
Cíclidos , Animales , Natación , Material Particulado/toxicidad , Metabolismo Energético , Consumo de Oxígeno
20.
Braz J Med Biol Res ; 56: e12713, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37493771

RESUMEN

Mesenchymal stromal/stem cells stem (MSC) have been widely studied due to their great potential for application in tissue engineering and regenerative and translational medicine. In MSC-based therapy for human diseases, cell proliferation is required to obtain a large and adequate number of cells to ensure therapeutic efficacy. During in vitro culture, cells are under an artificial environment and manipulative stress that can affect genetic stability. Several regulatory agencies have established guidelines to ensure greater safety in cell-based regenerative and translational medicine, but there is no specific definition about the maximum number of passages that ensure the lowest possible risk in MSC-based regenerative medicine. In this context, the aim of this study was to analyze DNA damage and chromosome alterations in adipose-derived mesenchymal stromal cells (ADMSC) until the eleventh passage and to provide additional subsidies to regulatory agencies related to number of passages in these cells. Thus, two methods in genetic toxicology were adopted: comet assay and micronucleus test. The comet assay results showed an increase in DNA damage from the fifth passage onwards. The micronucleus test showed a statistically significant increase of micronucleus from the seventh passage onwards, indicating a possible mutagenic effect associated with the increase in the number of passages. Based on these results, it is important to emphasize the need to assess genetic toxicology and inclusion of new guidelines by regulatory agencies to guarantee the safety of MSC-based therapies for human diseases.


Asunto(s)
Células Madre Mesenquimatosas , Humanos , Ingeniería de Tejidos , Inestabilidad Genómica , Proliferación Celular , Mutagénesis , Diferenciación Celular , Células del Estroma
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA