RESUMO
The mode of exploration of the Brazilian semiarid has followed since the colonization of Brazil, a model of exacerbated extraction of the natural resources. This model has led to the severe environmental degradation of this region and mainly of its main biome, the Caatinga. In this context, several farmers have sought new forms of production, with emphasis on Agroforestry Systems (SAFs). This system consists of combining trees, shrubs, agricultural crops and animals in the same area, seeking to maximize socioeconomic, cultural and environmental values, since they have the potential to enhance the production of environmental goods and services. Although this practice has been practiced for decades by farmers in the country, its study as a science is relatively recent, and its potentiality is still unknown by many. Several studies demonstrate the application of this technique in the semi-arid region, with results that show improvements in soil quality, improved nutrient cycling, biological nutrient fixation, improved income generation among small producers, among others. However, there is still a lack of incentive for government agencies to further disseminate this practice among farmers in this region, as well as information on the social, environmental and economic benefits of SAFs.
O modo de exploração do semiárido brasileiro conduziu-se desde a colonização, na exploração acentuada dos recursos naturais. Esse modelo tem levado a degradação ambiental severa dessa região e principalmente, do seu principal bioma, a Caatinga. Nesse contexto, diversos agricultores têm buscado novas formas de produção, dando destaque aos Sistemas Agroflorestais (SAFs). Esses sistemas consistem na combinação de árvores, arbustos, cultivos agrícolas e animais na mesma área, procurando a maximização dos valores socioeconômicos, culturais e ambientais, uma vez que, apresentam capacidade de potencializar a produção de bens e serviços ambientais. Essa prática já vem sendo utilizada durante décadas, por agricultores espalhados no país. O estudo como ciência é relativamente recente, sendo sua potencialidade ainda desconhecida. Diversos trabalhos demonstram a aplicação dessa técnica no semiárido, com resultados que mostram melhorias na qualidade do solo, na ciclagem de nutrientes, na fixação biológica, na geração de renda, entre outros. No entanto, ainda falta incentivo do poder público para uma maior disseminação nessa prática, entre os agricultores dessa região, sobretudo, a falta de informações sobre os benefícios sociais, ambientais e econômicos oriundos dos SAFs.
Assuntos
Agricultura Florestal , Integração de Sistemas , Zona Semiárida , Brasil , Desenvolvimento SustentávelRESUMO
The mode of exploration of the Brazilian semiarid has followed since the colonization of Brazil, a model of exacerbated extraction of the natural resources. This model has led to the severe environmental degradation of this region and mainly of its main biome, the Caatinga. In this context, several farmers have sought new forms of production, with emphasis on Agroforestry Systems (SAFs). This system consists of combining trees, shrubs, agricultural crops and animals in the same area, seeking to maximize socioeconomic, cultural and environmental values, since they have the potential to enhance the production of environmental goods and services. Although this practice has been practiced for decades by farmers in the country, its study as a science is relatively recent, and its potentiality is still unknown by many. Several studies demonstrate the application of this technique in the semi-arid region, with results that show improvements in soil quality, improved nutrient cycling, biological nutrient fixation, improved income generation among small producers, among others. However, there is still a lack of incentive for government agencies to further disseminate this practice among farmers in this region, as well as information on the social, environmental and economic benefits of SAFs.(AU)
O modo de exploração do semiárido brasileiro conduziu-se desde a colonização, na exploração acentuada dos recursos naturais. Esse modelo tem levado a degradação ambiental severa dessa região e principalmente, do seu principal bioma, a Caatinga. Nesse contexto, diversos agricultores têm buscado novas formas de produção, dando destaque aos Sistemas Agroflorestais (SAFs). Esses sistemas consistem na combinação de árvores, arbustos, cultivos agrícolas e animais na mesma área, procurando a maximização dos valores socioeconômicos, culturais e ambientais, uma vez que, apresentam capacidade de potencializar a produção de bens e serviços ambientais. Essa prática já vem sendo utilizada durante décadas, por agricultores espalhados no país. O estudo como ciência é relativamente recente, sendo sua potencialidade ainda desconhecida. Diversos trabalhos demonstram a aplicação dessa técnica no semiárido, com resultados que mostram melhorias na qualidade do solo, na ciclagem de nutrientes, na fixação biológica, na geração de renda, entre outros. No entanto, ainda falta incentivo do poder público para uma maior disseminação nessa prática, entre os agricultores dessa região, sobretudo, a falta de informações sobre os benefícios sociais, ambientais e econômicos oriundos dos SAFs.(AU)
Assuntos
Integração de Sistemas , Agricultura Florestal , Zona Semiárida , Brasil , Desenvolvimento SustentávelRESUMO
The purpose of this study was to compare the effects of light-emitting diode (LED) irradiation and whole-body vibration (WBV) delivered either in isolation or combination (LED + WBV), warm-up (WU), and a control (C) treatment on performance during a sprint bicycle exercise. Ten cyclists performed a 30-second sprint cycle test under these conditions. The LED light was applied at 4 points bilaterally. Whole-body vibration consisted of 5 minutes of squats associated with WBV. LED + WBV consisted of WBV followed by LED therapy. Warm-up consisted of 17 minutes of moderate-intensity bicycle exercise. Control consisted of 10 minutes at rest. Blood lactate (BL) and ammonia (BA) levels and skin temperature (ST) were determined. Peak power (842 ± 117 vs. 800 ± 106 vs. 809 ± 128 W [p = 0.02 and p = 0.01]), relative power (12.1 ± 1.0 vs. 11.5 ± 0.9 vs. 11.6 ± 1.0 W·kg [p = 0.02 and p = 0.02]), and relative work (277 ± 23 vs. 263 ± 24 vs. 260 ± 23 J·kg [p = 0.02 and p = 0.003]) were higher in the WU group compared with the control and LED groups. In the LED + WBV group, peak (833 ± 115 vs. 800 ± 106 W [p = 0.02]) and relative (11.9 ± 0.9 vs. 11.5 ± 0.9 W·kg [p = 0.02]) power were higher than those in the control group, and relative work (272 ± 22 vs. 260 ± 23 J·kg [p = 0.02]) were improved compared with the LED group. There were no differences for BL, BA, and ST. The findings of this study confirmed the effectiveness of a warm-up as a preparatory activity and demonstrated that LED + WBV and WBV were as effective as WU in improving cyclist performance during a sprint bicycle exercise.
Assuntos
Luz , Esforço Físico/fisiologia , Vibração , Exercício de Aquecimento/fisiologia , Adolescente , Adulto , Amônia/sangue , Teste de Esforço , Humanos , Ácido Láctico/sangue , Masculino , Modalidades de Fisioterapia , Temperatura Cutânea , Adulto JovemRESUMO
OBJECTIVE: This work aimed to investigate the biochemical changes associated with low-level laser therapy (LLLT) using 660 and 780 nm, on a well-established experimental model of osteoarthritis (OA) in the knees of rats with induced collagenase, using histomorphometry and Raman spectroscopy. MATERIALS AND METHODS: Thirty-six Wistar rats were divided into four groups: control (GCON, n=9), collagenase without treatment (GCOL, n=9), collagenase with LLLT 660 nm treatment (G660, n=8), and collagenase with LLLT 780 nm treatment (G780, n=10). LLLT protocol was: 30 mW power output, 10 sec irradiation time, 0.04 cm(2) spot size, 0.3 J energy, 0.75 W/cm(2) irradiance, and 7.5 J/cm(2) fluence per session per day, during 14 days. Then, knees were withdrawn and submitted to histomorphometry and Raman spectroscopy analysis. Principal components analysis (PCA) and Mahalanobis distance were employed to characterize the spectral findings. RESULTS: Histomorphometry revealed a significant increase in the amount of collagen III for the group irradiated with 660 nm. The Raman bands at 1247, 1273, and 1453 cm(-1) (from principal component score PC2), attributed to collagen type II, and 1460 cm(-1) (from PC3), attributed to collagen type III, suggested that the LLLT causes acceleration in cellular activity, especially on the cells that repair cartilage, accelerating the breakdown of cartilage destroyed by collagenase and stimulating the fibroblast to synthesize repairing collagen III. CONCLUSIONS: LLLT accelerated the initial breakdown of cartilage destroyed by collagenase and stimulated the fibroblast to synthesize the repairing collagen III, suggesting a beneficial effect of LLLT on OA.
Assuntos
Terapia com Luz de Baixa Intensidade , Osteoartrite/radioterapia , Análise Espectral Raman , Animais , Colagenases/análise , Osteoartrite/patologia , Ratos , Ratos WistarRESUMO
Rheumatoid arthritis (RA) is an autoimmune inflammatory disease of unknown etiology. Treatment of RA is very complex, and in the past years, some studies have investigated the use of low-level laser therapy (LLLT) in treatment of RA. However, it remains unknown if LLLT can modulate early and late stages of RA. With this perspective in mind, we evaluated histological aspects of LLLT effects in different RA progression stages in the knee. It was performed a collagen-induced RA model, and 20 male Wistar rats were divided into 4 experimental groups: a non-injured and non-treated control group, a RA non-treated group, a group treated with LLLT (780 nm, 22 mW, 0.10 W/cm(2), spot area of 0.214 cm(2), 7.7 J/cm(2), 75 s, 1.65 J per point, continuous mode) from 12th hour after collagen-induced RA, and a group treated with LLLT from 7th day after RA induction with same LLLT parameters. LLLT treatments were performed once per day. All animals were sacrificed at the 14th day from RA induction and articular tissue was collected in order to perform histological analyses related to inflammatory process. We observed that LLLT both at early and late RA progression stages significantly improved mononuclear inflammatory cells, exudate protein, medullary hemorrhage, hyperemia, necrosis, distribution of fibrocartilage, and chondroblasts and osteoblasts compared to RA group (p < 0.05). We can conclude that LLLT is able to modulate inflammatory response both in early as well as in late progression stages of RA.
Assuntos
Artrite Reumatoide/patologia , Artrite Reumatoide/radioterapia , Terapia com Luz de Baixa Intensidade , Animais , Artrite Reumatoide/induzido quimicamente , Condrócitos/patologia , Condrócitos/efeitos da radiação , Colágeno/efeitos adversos , Modelos Animais de Doenças , Exsudatos e Transudatos/efeitos da radiação , Fibrocartilagem/patologia , Fibrocartilagem/efeitos da radiação , Masculino , Osteoblastos/patologia , Osteoblastos/efeitos da radiação , Ratos , Ratos WistarRESUMO
The aim of this study was to evaluate the process of bone repair in rats submitted to low-level laser therapy using optical densitometry. A total of 45 rats which underwent femoral osteotomy were randomly distributed into three groups: control (group I) and laser-treated groups using wavelengths in the red (λ, 660-690 nm) and in the infrared (λ, 790-830 nm) spectra (group II and group III, respectively). The animals (five per group) were killed after 7, 14, and 21 days and the femurs were removed for optical densitometry analysis. Optical density showed a significant increase in the degree of mineralization (gray level) in both groups treated with the laser after 7 days. After 14 days, only the group treated with laser therapy in the infrared spectrum showed higher bone density. No differences were observed between groups after 21 days. Such results suggest the positive effect of low-level laser therapy in bone repair is time- and wavelength-dependent. In addition, our results have confirmed that optical densitometry technique can measure bone mineralization status.
Assuntos
Regeneração Óssea/efeitos da radiação , Densitometria/métodos , Terapia com Luz de Baixa Intensidade/métodos , Animais , Calcificação Fisiológica/efeitos da radiação , Fêmur/cirurgia , Raios Infravermelhos , Masculino , Osteotomia , Ratos , Ratos WistarRESUMO
A variety of treatments for tendinopathies is currently used or has been trialed. However, in fact, there is a remarkably little evidence that any conventional therapies are effective. In the last years, low-level laser therapy (LLLT) has been showing interesting results in inflammatory modulation in different musculoskeletal disorders, but the optimal parameters and mechanisms behind these effects are not fully understood. The aim of this study is to investigate if the LLLT modulates the acute and chronic phase of collagenase-induced tendinitis in rat by interfering in mRNA expression for matrix metalloproteinases (MMP13 and MMP1), vascular endothelial growth factor (VEGF), and anti-inflammatory mediator (interleukin (IL)-10). For such, tendinitis was induced by collagenase injection in male Wistar rats. Animals were treated with LLLT (780 nm, potency of 22 mW, 107 mW/cm(2), energy density of 7.5 J/cm(2), and energy delivered of 1.54 J) with different number of treatments in accordance with the inflammatory phase analyzed. LLLT was able to modulate mRNA gene expression of IL-10, VGEF, MMP1, and MMP13 both in acute than in chronic inflammatory phase (p<0.05). Our results suggest that LLLT with parameters employed in the present study was able to modulate IL-10, VEGF, MMP1, and MMP13 mRNA gene expression both in acute than in chronic tendon inflammation. However, further studies are needed to establish optimal parameters for LLLT.
Assuntos
Terapia com Luz de Baixa Intensidade , Tendinopatia/radioterapia , Doença Aguda , Animais , Doença Crônica , Colagenases/administração & dosagem , Modelos Animais de Doenças , Expressão Gênica/efeitos da radiação , Inflamação/etiologia , Inflamação/genética , Inflamação/radioterapia , Mediadores da Inflamação/metabolismo , Interleucina-10/genética , Masculino , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 13 da Matriz/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Tendinopatia/etiologia , Tendinopatia/genética , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
There is a current lack of clarity regarding the use of Fourier-transform infrared spectroscopy (FT-IR) to evaluate intramuscular concentrations of creatine (Cr). Thus, the aim of this study was to assess the FT-IR spectral features of tibialis anterior muscle in rats submitted in conditions that were expected to perturb the Cr pool. First, an experiment was performed to ensure that FT-IR was able to detect the Cr intramuscular in sedentary and supplemented rats (Experiment 1). The effect of physical exercise on spectral muscle features was then examined, especially in relation to the spectroscopy markers (Experiment 2). Using pure Cr (control), it was possible to verify that only the peaks centered at 1308 and 1396 cm(-1) of all the spectra showed the same peak positions, indicating these FT-IR shifts as indirect markers of Cr intramuscular content. Experiment 2 revealed a higher Cr content for the Cr-supplemented and exercised animals than the rats of other groups. In conclusion, it was demonstrated that FT-IR spectroscopy using 1396 cm(-1) and mainly 1308 band was able to monitor Cr muscle content in rats sedentary, Cr-supplemented, and submitted to physical training. Besides, FT-IR could be a feasible method for the nondestructive assessment of Cr skeletal muscle content.
Assuntos
Creatina/análise , Músculo Esquelético/química , Condicionamento Físico Animal/fisiologia , Animais , Creatina/metabolismo , Masculino , Músculo Esquelético/metabolismo , Ratos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
The influence of creatine (Cr) supplementation on cortical and trabecular bone from ovariectomized rats was studied using FT-Raman spectroscopy. The intensity of organic-phase Raman bands was compared to mineral phase ones. Twenty-one female Wistar rats aged 3 months were divided into three groups (n = 7 per group): ovariectomized (OVX), ovariectomized treated with creatine (CRE) and sham-operated (SHAM) groups. Creatine supplementation (300 mg kg(-1) day(-1)) was provided for 8 weeks, starting 12 weeks after ovariectomy. FT-Raman spectroscopy was performed on the right medial femoral mid-shaft (cortical bone) and third lumbar vertebral body (trabecular bone). The integrated intensities of mineral phase (phosphate and carbonate bands at 959 and 1,071 cm(-1), respectively) and organic phase (amide I band at 1,665 cm(-1)) Raman bands were analyzed. The mineral-to-matrix (phosphate/amide I), carbonate-to-phosphate, and carbonate-to-amide I ratios were analyzed to assess bone quality. The phosphate content on trabecular bone was higher in the CRE group than the OVX group (p < 0.05). No significant changes in mineral or organic phases on cortical bone were observed. A radiographic assessment of bone density was encouraging as the same findings were showed by Raman intensity of phosphate from cortical (r(2) = 0.8037) and trabecular bones (r(2) = 0.915). Severe ovariectomy-induced bone loss was confirmed by FT-Raman spectroscopy. The results suggest that the chemical composition of trabecular bone tissue may be positively influenced by Cr supplementation after ovariectomy.
Assuntos
Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Creatina/farmacologia , Suplementos Nutricionais , Osteoporose/tratamento farmacológico , Animais , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Creatina/uso terapêutico , Feminino , Osteoporose/patologia , Ovariectomia , Placebos , Radiografia , Ratos , Ratos Wistar , Análise Espectral RamanRESUMO
This study evaluated the functional and quantitative differences between the early and delayed use of phototherapy in crushed median nerves. After a crush injury, low-level laser therapy (GaAs) was applied transcutaneously at the injury site, 3 min daily, with a frequency of five treatments per week for 2 weeks. In the early group, the first laser treatment started immediately after surgery, and in the delayed group, after 7 days. The grasping test was used for functional evaluation of the median nerve, before, 10, and 21 days after surgery, when the rats were killed. Three segments of the median nerve were analyzed histomorphometrically by light microscopy and computer analysis. The following features were observed: myelinated fiber and axon diameters, myelin sheath area, g-ratio, density and number of myelinated fibers, and area and number of capillaries. In the proximal segment (site of crush), the nerves of animals submitted to early and delayed treatment showed myelinated fiber diameter and myelin sheath area significantly larger compared to the untreated group. In the distal segment, the myelin sheath area was significantly smaller in the untreated animals compared to the delayed group. The untreated, early, and delayed groups presented a 50, 57, and 81% degree of functional recovery, respectively, at 21 days after injury, with a significant difference between the untreated and delayed groups. The results suggest that the nerves irradiated with low-power laser exhibit myelinated fibers of greater diameter and a better recovery of function.