Evidence demonstrates that sympathetic nervous system (SNS) activation causes osteopenia via b 2 -adrenoceptor (b2-AR) signaling. Here we show that female mice with chronic sympathetic hyperactivity owing to double knockout of adrenoceptors that negatively regulate norepinephrine release, a 2A -AR and a 2C -AR (a 2A /a 2C -ARKO), present an unexpected and generalized phenotype of high bone mass with decreased bone resorption and increased formation. In a 2A /a 2C -ARKO versus wild-type (WT) mice, micro-computed tomographic (mCT) analysis showed increased, better connected, and more plate-shaped trabeculae in the femur and vertebra and increased cortical thickness in the vertebra, whereas biomechanical analysis showed increased tibial and femoral strength. Tibial mRNA expression of tartrate-resistant acid phosphatase (TRACP) and receptor activator of NF-kB (RANK), which are osteoclast-related factors, was lower in knockout (KO) mice. Plasma leptin and brain mRNA levels of cocaine amphetamine-regulated transcript (CART), which are factors that centrally affect bone turnover, and serum levels of estradiol were similar between mice strains. Tibial b 2 -AR mRNA expression also was similar in KO and WT littermates, whereas a 2A -, a 2B -and a 2C -AR mRNAs were detected in the tibia of WT mice and in osteoblast-like MC3T3-E1 cells. By immunohistochemistry, we detected a 2A -, a 2B -, a 2C -and b 2 -ARs in osteoblasts, osteoclasts, and chondrocytes of 18.5-day-old mouse fetuses and 35-day-old mice. Finally, we showed that isolated osteoclasts in culture are responsive to the selective a 2 -AR agonist clonidine and to the nonspecific a-AR antagonist phentolamine. These findings suggest that b 2 -AR is not the single adrenoceptor involved in bone turnover regulation and show that a 2 -AR signaling also may mediate the SNS actions in the skeleton. ß
The rapid population growth has driven the demand for more food, fiber, energy, and water, which is associated to an increase in the need to use natural resources in a more sustainable way. The use of precision agriculture machinery and equipment since the 1990s has provided important productive gains and maximized the use of agricultural inputs. The growing connectivity in the rural environment, in addition to its greater integration with data from sensor systems, remote sensors, equipment, and smartphones have paved the way for new concepts from the so-called Agriculture 4.0 or Digital Agriculture. This article presents the results of a survey carried out with 504 Brazilian farmers about the digital technologies in use, as well as current and future applications, perceived benefits, and challenges. The questionnaire was prepared, organized, and made available to the public through the online platform LimeSurvey and was available from 17 April to 2 June 2020. The primary data obtained for each question previously defined were consolidated and analyzed statistically. The results indicate that 84% of the interviewed farmers use at least one digital technology in their production system that differs according to technological complexity level. The main perceived benefit refers to the perception of increased productivity and the main challenges are the acquisition costs of machines, equipment, software, and connectivity. It is also noteworthy that 95% of farmers would like to learn more about new technologies to strengthen the agricultural development in their properties.
RESUMO -Conduziu-se um experimento com o objetivo de verificar o efeito de diferentes níveis de fósforo disponível (Pd) e de cálcio (Ca) na dieta sobre o desempenho, a qualidade dos ovos e o perfil nutricional do tecido ósseo de codornas japonesas durante a fase inicial de postura. Foram utilizadas 700 codornas japonesas, com 61 dias de idade, distribuídas em 70 unidades experimentais de dez aves. O delineamento foi inteiramente casualizado em esquema fatorial 5 × 2, composto de cinco níveis de Pd (0,15; 0,25; 0,35; 0,45 e 0,55%) e dois de Ca (2,5 e 3,2%), com sete repetições por tratamento. As dietas experimentais foram isoprotéicas (20,0% PB), isocalóricas (2.900 kcal EM/kg) e isoaminoacídicas. Os níveis de Pd influenciaram de forma quadrática a altura e o diâmetro médio dos ovos, o teor de Ca na casca e a porcentagem de Ca (2,5%Ca) e P (3,2%Ca) nos ossos. Houve melhora linear na produção de ovos comercializáveis e na porcentagem de P nos ossos (menor nível da Ca testado) até os níveis de 0,31 e 0,51% de Pd, respectivamente, na dieta. Com o aumento dos níveis de Pd na dieta, a conversão alimentar por dúzia de ovos piorou de forma linear e a porcentagem e o peso de gema reduziram até os níveis 0,40 e 0,25% de Pd, respectivamente, na dieta. O peso, a porcentagem e a espessura de casca, o peso específico, o teor de Ca na casca e a porcentagem de Ca nos ossos foram influenciados pelos níveis de Ca na dieta. Não houve influência dos níveis de Ca e Pd sobre a produção de ovos, o consumo de ração, a massa de ovos, a conversão alimentar por massa de ovos, a viabilidade, o peso médio final das aves e a porcentagem e o peso de albúmen nos ovos. Níveis dietéticos de 2,5 e 0,31% de Pd são suficientes para proporcionar bom desempenho produtivo e para manutenção satisfatória da qualidade dos ovos e do perfil nutricional do tecido ósseo de codornas japonesas durante a fase inicial de postura.Palavras-chave: Coturnix coturnix japonica, desempenho produtivo, qualidade do ovo, perfil nutricional Levels of phosphorus and calcium in diets of laying Japanese quailsABSTRACT -An experiment was conducted with the objective to verify the effect of different levels of available phosphorus (aP) and of calcium (Ca) in the diet on the performance, the quality of eggs and the nutritional status of the bone tissue of japanese quails during the initial laying phase. A total of 700 japanese quails, with 61 days of age, distributed in 70 experimental units with 10 birds each were used. A completely randomized experimental design was use, in a 5 × 2 factorial arrangement with five levels of aP (0.15; 0.25; 0.35; 0.45 e 0,55%) and two levels of Ca (2.5 e 3.2%), with seven replicates per treatments. The experimental diets were isoprotéicas (20.0% CP), isocalóricas (2.900 kcal ME/kg) and isoaminoacids.The levels of aP influenced by a quadratic form, the height and the average diameter of the eggs, the Ca egg shell content and percentage of Ca (2.5% Ca) and P (3.2% Ca) in the bones. There was a linear improvement for the commercial egg production a...
RESUMO -O experimento foi realizado com objetivo de estudar o uso de mananoligossacarídeos (standard e concentrado) em rações para frangos de corte. Foram utilizados 1.080 pintos de corte machos da marca Ross, com peso médio inicial de 42 g, distribuídos em um delineamento inteiramente ao acaso, com seis tratamentos e nove repetições de 20 aves por unidade experimental. As aves foram criadas em cama de maravalha reaproveitada, utilizada anteriormente por outro lote. gain, feed intake, feed:gain ratio, viability and prime cuts yield were evaluated. In the period from 1 to 21 days old, no significant differences across the treatments on feed intake, feed:gain ratio, and viability were found. The results of performance of birds fed diet containing MOS ST or MOS AT combined or not with the antibiotic, did not differ form those of treatments with avilamicin and control. In the period from 1 to 42 days old, mannanoligosaccharides standard (MOS ST) combined or not with avilamicin, increased weight gain, whereas the mannaoligosaccharide high concentration (MOS AT) showed did not affect weight gain. Feed:gain ratio, feed intake and viability were not affected by the different treatments, but the additives increased prime cuts yield and it decreased abdominal fat.Key Words: additive, antibiotic, feed efficiency, MOS IntroduçãoA escolha de um bom promotor de crescimento deve basear-se em dois fatores: aspecto econômico e segurança. É inquestionável que a relação custo:benefício favorece o uso de antibióticos como aditivo. Todavia, a segurança alimentar começou a ser questionada, principalmente em razão do uso rotineiro desse aditivo na alimentação animal.O uso de drogas estratégicas para a saúde humana tem sido limitado na Europa por favorecer o desenvolvimento
To investigate whether thyroid hormone (TH) interacts with the sympathetic nervous system (SNS) to modulate bone mass and structure, we studied the effects of daily T3 treatment in a supraphysiological dose for 12 wk on the bone of young adult mice with chronic sympathetic hyperactivity owing to double-gene disruption of adrenoceptors that negatively regulate norepinephrine release, α(2A)-AR, and α(2C)-AR (α(2A/2C)-AR(-/-) mice). As expected, T3 treatment caused a generalized decrease in the areal bone mineral density (aBMD) of WT mice (determined by DEXA), followed by deleterious effects on the trabecular and cortical bone microstructural parameters (determined by μCT) of the femur and vertebra and on the biomechanical properties (maximum load, ultimate load, and stiffness) of the femur. Surprisingly, α(2A/2C)-AR(-/-) mice were resistant to most of these T3-induced negative effects. Interestingly, the mRNA expression of osteoprotegerin, a protein that limits osteoclast activity, was upregulated and downregulated by T3 in the bone of α(2A/2C)-AR(-/-) and WT mice, respectively. β1-AR mRNA expression and IGF-I serum levels, which exert bone anabolic effects, were increased by T3 treatment only in α(2A/2C)-AR(-/-) mice. As expected, T3 inhibited the cell growth of calvaria-derived osteoblasts isolated from WT mice, but this effect was abolished or reverted in cells isolated from KO mice. Collectively, these findings support the hypothesis of a TH-SNS interaction to control bone mass and structure of young adult mice and suggests that this interaction may involve α2-AR signaling. Finally, the present findings offer new insights into the mechanisms through which TH regulates bone mass, structure, and physiology.
New strategies to fulfill craniofacial bone defects have gained attention in recent years due to the morbidity of autologous bone graft harvesting. We aimed to evaluate the in vivo efficacy of bone tissue engineering strategy using mesenchymal stem cells associated with two matrices (bovine bone mineral and α-tricalcium phosphate), compared to an autologous bone transfer. A total of 28 adult, male, non-immunosuppressed Wistar rats underwent a critical-sized osseous defect of 5 mm diameter in the alveolar region. Animals were divided into five groups. Group 1 (n = 7) defects were repaired with autogenous bone grafts; Group 2 (n = 5) defects were repaired with bovine bone mineral free of cells; Group 3 (n = 5) defects were repaired with bovine bone mineral loaded with mesenchymal stem cells; Group 4 (n = 5) defects were repaired with α-tricalcium phosphate free of cells; and Group 5 (n = 6) defects were repaired with α-tricalcium phosphate loaded with mesenchymal stem cells. Groups 2–5 were compared to Group 1, the reference group. Healing response was evaluated by histomorphometry and computerized tomography. Histomorphometrically, Group 1 showed 60.27% ± 16.13% of bone in the defect. Groups 2 and 3 showed 23.02% ± 8.6% (p = 0.01) and 38.35% ± 19.59% (p = 0.06) of bone in the defect, respectively. Groups 4 and 5 showed 51.48% ± 11.7% (p = 0.30) and 61.80% ± 2.14% (p = 0.88) of bone in the defect, respectively. Animals whose bone defects were repaired with α-tricalcium phosphate and mesenchymal stem cells presented the highest bone volume filling the defects; both were not statistically different from autogenous bone.
Previous studies showed anabolic effects of GC-1, a triiodothyronine (T3) analogue that is selective for both binding and activation functions of thyroid hormone receptor (TR) beta1 over TRalpha1, on bone tissue in vivo. The aim of this study was to investigate the responsiveness of rat (ROS17/2.8) and mouse (MC3T3-E1) osteoblast-like cells to GC-1. As expected, T3 inhibited cellular proliferation and stimulated mRNA expression of osteocalcin or alkaline phosphatase in both cell lineages. Whereas equimolar doses of T3 and GC-1 equally affected these parameters in ROS17/2.8 cells, the effects of GC-1 were more modest compared to those of T3 in MC3T3-E1 cells. Interestingly, we showed that there is higher expression of TRalpha1 than TRbeta1 mRNA in rat (approximately 20-90%) and mouse (approximately 90-98%) cell lineages and that this difference is even higher in mouse cells, which highlights the importance of TRalpha1 to bone physiology and may partially explain the modest effects of GC-1 in comparison with T3 in MC3T3-E1 cells. Nevertheless, we showed that TRbeta1 mRNA expression increases (approximately 2.8- to 4.3-fold) as osteoblastic cells undergo maturation, suggesting a key role of TRbeta1 in mediating T3 effects in the bone forming cells, especially in mature osteoblasts. It is noteworthy that T3 and GC-1 induced TRbeta1 mRNA expression to a similar extent in both cell lineages (approximately 2- to 4-fold), indicating that both ligands may modulate the responsiveness of osteoblasts to T3. Taken together, these data show that TRbeta selective T3 analogues have the potential to directly induce the differentiation and activity of osteoblasts.
RESUMO -Conduziu-se um experimento com o objetivo de verificar o efeito de níveis de fósforo disponível (Pd) na dieta sobre o desempenho, a qualidade dos ovos, o tecido ósseo e as porcentagens de fósforo (P), cálcio (Ca) e magnésio (Mg) nas excretas produzidas por codornas durante o terço final de postura. Foram utilizadas 300 codornas japonesas com 313 dias de idade, distribuídas em 30 unidades experimentais de dez aves. O delineamento foi inteiramente casualizado, composto de cinco níveis de Pd (0,15; 0,25; 0,35; 0,45 e 0,55%), com seis repetições por tratamento. As dietas experimentais foram isoproteicas (20,0% PB), isocalóricas (2.900 kcal EM/kg), isocálcicas (3,0% Ca) e isoaminoacídicas. O aumento dos níveis de Pd na dieta aumentou linearmente os teores de Ca e Mg na tíbia, entretanto reduziu linearmente a altura dos ovos analisados. Observou-se efeito quadrático sobre o peso específico, o peso e a porcentagem de casca, a porcentagem de cálcio na casca e de fósforo na tíbia, cujos pontos de máxima foram atingidos com a utilização de 0,43; 0,41; 0,42; 0,27 e 0,42% Pd, respectivamente. Efeitos quadráticos também foram observados para excreção de Ca, cinzas e P, cujos valores máximos foram obtidos com a utilização de 0,34; 0,30 e 0,43% Pd na dieta, respectivamente. Nos demais parâmetros avaliados, não houve efeito dos níveis de Pd. Dietas contendo 0,15% Pd atendem satisfatoriamente às exigências para desempenho e manutenção da integridade física do ovo, além de reduzir a excreção de fósforo sem provocar perda de ovos por problemas de casca nem ocorrência de fadiga de gaiola por enfraquecimento do sistema ósseo, embora seja observada redução na mineralização da casca e do tecido ósseo de codornas japonesas no terço final do ciclo de produção (45 a 57 semanas de idade).Palavras-chave: Coturnix coturnix japonica, desempenho produtivo, qualidade do ovo, tecido ósseo Available phosphorus levels for Japanese quail diets from 45 to 57 weeks of age ABSTRACT -An experiment was conducted aiming to verify the effect of different levels of available phosphorus (AP) in the diet on performance, egg quality, bone tissue and percentages of P, Ca and Mg in excreta produced by quails during the final third of the production cycle. A total of 300 Japanese quails, with 313 days of age, was assigned to 30 experimental units of ten birds. A completely randomized design was used, with five levels of AP (0.15, 0.25, 0.35, 0.45 and 0.55%), with six replicates per treatments. The experimental diets were isoproteic (20.0% CP), isocaloric (2.900 kcal ME/kg), isocalcium (3.0% Ca) and isoaminoacidic. The increasing levels of AP in the diet linearly increased the concentration of Ca and Mg in the tibia; however, it linearly reduced the height of eggs analyzed. There was quadratic effect for specific gravity, weight and shell percentage, shell percentage of Ca and P in the tibia, achieving maximum points with the use of 0.43, 0.41, 0.42, 0.27 and 0.42% AP, respectively. Quadratic effects were also observed for excretion of Ca, P and ash, yie...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.