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1.
Nutr Rev ; 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36474436

RESUMO

CONTEXT: Studies using experimental models have demonstrated that prebiotics are involved in antiosteoporotic mechanisms. OBJECTIVE: This study was conducted to determine the impact of supplementation with prebiotics in the basal diet of ovariectomized rats with induced osteoporosis as a preclinical model. METHODS: A comprehensive systematic search was carried out in the electronic databases PubMed, Science Direct, Web of Science, Scielo, and Google through March 2022 for studies that investigated the impact of prebiotics on bone mineral density (BMD), bone mineral content (BMC), and bone biomechanics. RESULTS: The search returned 844 complete articles, abstracts, or book chapters. After detailed screening, 8 studies met the inclusion criteria. Rats (n = 206), were randomly divided between control and treatment groups. Weighted mean differences (WMDs) with the 95%CIs were used to estimate the combined effect size. Compared with the control group, dietary intake of prebiotics significantly increased bone density in the BMD subgroups, with WMDs as follows: 0.03 g/cm3, 95%CI, 0.01-0.05, P < 0.00001, n = 46; and 0.00 g/cm2, 95%CI, 0.00-0.02, P < 0.00001, n = 81; total BMD: WMD, 0.01, 95%CI, 0.01-0.02, P < 0.00001, n = 127; bone content in BMC: WMD, 0.02 g, 95%CI, 0.00-0.04, P = 0.05, n = 107; and the 3-point-bend test: WMD, 15.20 N, 95%CI, 5.92-24.47, P = 0.00001, n = 120. CONCLUSION: Prebiotics improve indicators of osteoporosis, BMD, BMC, and bone biomechanics in ovariectomized rats. More studies are needed to increase the level of evidence. SYSTEMIC REVIEW REGISTRATION: Systematic Review Protocol for Animal Intervention Studies.

2.
Nutr Rev ; 80(2): 157-164, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-34010402

RESUMO

CONTEXT: Inflammatory bowel diseases are chronic, relapsing diseases that compromise life quality and expectancy. The increased incidence and prevalence of these diseases reinforce the need for research on prevention, therapy, and management innovations. Synbiotics (ie, probiotic plus prebiotic combinations) are suggested as an alternative or complementary therapy to conventional treatments for inflammatory bowel disease. OBJECTIVE: The aim for this systematic review was to gather and analyze data from randomized controlled trials to provide more information to increase the current evidence level about the safety and efficacy of synbiotic use as a supplemental treatment for ulcerative colitis. DATA SOURCES: Searches were performed in the Medline, Science Direct, Scielo, Scopus, and Embase databases between January 2017 and March 2019, using the keywords "colitis" and "synbiotics". DATA EXTRACTION: The data extraction method performed for each trial was based on the recommendations of the Consolidated Standards of Reporting Trials for randomized clinical trials. The trials included in this meta-analysis presented low risk of bias, based on the Cochrane Handbook for Systematic Reviews of Interventions guidelines. DATA ANALYSIS: The results demonstrated that synbiotics significantly improved colonic endoscopic and histologic scores, the Clinical Activity Index, serum C-reactive protein levels, intestinal microbiota, Bowel Habits Index, and levels of messenger RNAs, tumor necrosis factor-α, interleukin-1α, interleukin-10, and myeloperoxidase in the patients. In addition, the use of synbiotics increased probiotic microorganisms, reduced proinflammatory colonic cytokines, and elevated anti-inflammatory cytokines. CONCLUSIONS: Therefore, the results of this meta-analysis reinforce the evidence that synbiotics provide benefits to patients when used as an alternative or complementary therapy for those with ulcerative colitis.


Assuntos
Colite Ulcerativa , Doenças Inflamatórias Intestinais , Probióticos , Simbióticos , Colite Ulcerativa/terapia , Humanos , Doenças Inflamatórias Intestinais/terapia , Prebióticos , Probióticos/uso terapêutico
3.
Vet World ; 14(5): 1210-1219, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34220123

RESUMO

BACKGROUND AND AIM: The prebiotics, mannan-oligosaccharides (MOS), demonstrate the ability to increase probiotic microorganisms and fixation and removal of pathogens associated with chronic systemic inflammation in the digestive system. Inflammatory processes play an important role in modulating the brain-intestinal axis, including maintaining male reproductive function and spermatogenesis and regulating stress. The aim of the present study was to evaluate the action of MOS on testosterone and corticosterone concentrations and the reproductive system development of rats in the growth phase as an animal model. MATERIALS AND METHODS: In total, 128 male rats were used, randomly divided into four experimental groups (n=32): Control; MOS 1; MOS 2; and MOS 3. From each group, eight animals were sacrificed in four experimental moments (14, 28, 42, and 56 days, respectively, moments 1, 2, 3, and 4) and hormonal measurements and histological evaluations were performed. RESULTS: The results revealed the effect of diet, MOS, and timing on testicle weight (p<0.05). At moments 3 and 4, the groups supplemented with MOS showed higher concentrations of testosterone and decreased corticosterone levels throughout the experimental period. Groups supplemented with MOS showed an increase in the frequency of relative sperm and sperm scores. The radii of the seminiferous tubules presented a significant statistical effect of the diet, moments, and diet + moment interaction. CONCLUSION: It was concluded that the three different MOS prebiotics brought forward sexual maturity.

4.
Braz Dent J ; 30(6): 634-640, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800759

RESUMO

Smoking is one of the main risk factor for periodontal disease, increasing its prevalence and severity. Probiotics emerged as an alternative for the prevention and treatment of many diseases, since it can modulate the host immune response and modify the modify the microbiome. Therefore, the aim of the present study is to evaluate the effects of probiotic administration on the periodontal tissues in rats exposed to cigarette smoke inhalation (CSI). Forty rats were allocated into the following groups (n=10): group C (control, without CSI and probiotic); group PROB (control+probiotic); group CSI (CSI) and group CSI+PROB (CSI+probiotic). Groups PROB and CSI+PROB received 2g of an association of probiotic microorganisms incorporated into the feed during 6 months. Groups CSI and CSI+PROB were exposed to CSI for 60 min daily. After six months all the animals were euthanized and the hemi-mandibles were collected and processed for microcomputed tomography analyses. Regarding the body weight of the animals, feed consumption was similar among the groups, however, after the second month groups C and PROB showed higher body weight gain when compared to groups CSI and CSI+PROB (p<0.05). Group CSI presented reduced bone mineral density (BMD), whereas group PROB showed the highest values (p=0.01). It can be concluded that administration of probiotics promoted an increase in BMD and, consequently, a protective effect on the mandibular bone structures in rats exposed to inhalation of cigarette smoke.


Assuntos
Probióticos , Animais , Densidade Óssea , Mandíbula , Ratos , Ratos Wistar , Fumar , Microtomografia por Raio-X
5.
Braz. dent. j ; 30(6): 634-640, Nov.-Dec. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1055457

RESUMO

Abstract Smoking is one of the main risk factor for periodontal disease, increasing its prevalence and severity. Probiotics emerged as an alternative for the prevention and treatment of many diseases, since it can modulate the host immune response and modify the modify the microbiome. Therefore, the aim of the present study is to evaluate the effects of probiotic administration on the periodontal tissues in rats exposed to cigarette smoke inhalation (CSI). Forty rats were allocated into the following groups (n=10): group C (control, without CSI and probiotic); group PROB (control+probiotic); group CSI (CSI) and group CSI+PROB (CSI+probiotic). Groups PROB and CSI+PROB received 2g of an association of probiotic microorganisms incorporated into the feed during 6 months. Groups CSI and CSI+PROB were exposed to CSI for 60 min daily. After six months all the animals were euthanized and the hemi-mandibles were collected and processed for microcomputed tomography analyses. Regarding the body weight of the animals, feed consumption was similar among the groups, however, after the second month groups C and PROB showed higher body weight gain when compared to groups CSI and CSI+PROB (p<0.05). Group CSI presented reduced bone mineral density (BMD), whereas group PROB showed the highest values (p=0.01). It can be concluded that administration of probiotics promoted an increase in BMD and, consequently, a protective effect on the mandibular bone structures in rats exposed to inhalation of cigarette smoke.


Resumo O tabagismo é um dos principais fatores de risco para a doença periodontal, aumentando sua prevalência e gravidade. Os probióticos surgiram como uma alternativa para a prevenção e tratamento de muitas doenças, uma vez que podem modular a resposta imune do hospedeiro e promover a modificação do microbioma. Dessa forma, o objetivo do presente estudo foi avaliar os efeitos da administração de probiótico sobre os tecidos periodontais em ratos expostos à inalação de fumaça de cigarro (CSI). Quarenta ratos foram divididos nos seguintes grupos (n=10): grupo C (controle, sem CSI e probiótico); grupo PROB (controle+probiótico); grupo CSI (CSI) e grupo CSI+PROB (CSI+probiótico). Os grupos PROB e CSI+PROB receberam 2g de uma associação de microrganismos probióticos incorporados à ração durante 6 meses. Os grupos CSI e CSI + PROB foram expostos à CSI por 60 minutos diários. Após seis meses, todos os animais foram eutanasiados e as hemi mandíbulas coletadas e processadas para análises de microtomografia computadorizada. Em relação ao peso corporal dos animais, o consumo de ração foi semelhante entre os grupos, porém, após o segundo mês os grupos C e PROB apresentaram maior ganho de peso quando comparados aos grupos CSI e CSI+PROB (p <0,05). O grupo CSI apresentou redução na densidade mineral óssea (DMO), enquanto que o grupo PROB apresentou os maiores valores (p=0,01). Pode-se concluir que a administração de probióticos promoveu aumento da DMO e, consequentemente, efeito protetor sobre as estruturas ósseas mandibulares em ratos expostos à inalação de fumaça de cigarro.


Assuntos
Animais , Ratos , Probióticos , Fumar , Densidade Óssea , Ratos Wistar , Microtomografia por Raio-X , Mandíbula
6.
J Sci Food Agric ; 99(1): 183-190, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29851070

RESUMO

BACKGROUND: The present study aimed to evaluate the nutritional, physiological and biochemical effects of dietary supplementation of an association of probiotic bacteria in rats intoxicated with chromium (VI). Ninety-six male rats, recently weaned, were randomly divided into eight groups (n = 12): Control, DK12, DK24 and DK36 (0, 0.12, 0.24 and 0.36 g kg-1 of K2 Cr2 O7 incorporated in the basal feed, respectively) and groups Prob, DK12 + Prob, DK24 + Prob and DK36 + Prob received a progressive dose of 0, 0.12, 0.24 and 0.36 g kg-1 of K2 Cr2 O7 incorporated in the basal feed and supplemented with 0.02 g kg-1 of an association of probiotic bacteria (Lactobacillus acidophilus, Enterococcus faecium, Bifidobacterium thermophilum and Bifidobacterium longum). RESULTS: After 90 days, we observed significant (P < 0.05) and dose-dependent alterations from incorporation of increasing doses of chromium (VI) related to nutritional, physiological and biochemical parameters. These changes were attenuated (P < 0.05) with probiotic supplementation. CONCLUSION: Supplementation with probiotics in the diet beneficially modified the nutritional and physiological parameters, as well as hepatic, renal, glycemic and lipid profiles, of animals intoxicated with increasing doses of K2 Cr2 O7 . © 2018 Society of Chemical Industry.


Assuntos
Intoxicação por Metais Pesados/tratamento farmacológico , Lactobacillaceae/fisiologia , Dicromato de Potássio/toxicidade , Probióticos/administração & dosagem , Animais , Avaliação Pré-Clínica de Medicamentos , Intoxicação por Metais Pesados/etiologia , Intoxicação por Metais Pesados/patologia , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Probióticos/análise , Distribuição Aleatória , Ratos , Ratos Wistar
7.
Ciênc. rural (Online) ; 49(5): e20180695, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1045351

RESUMO

ABSTRACT: Cigarette smoke in large centers is one of the most important causes of chronic inflammatory diseases in public health and is associated with a decrease in bone mass, consolidation process, and bone remodeling. Due to their ability to improve intestinal absorption and compete with pathogenic microorganisms, dietary supplementation with functional foods may contribute to improvement in bone quality. Therefore, the objective of this study was to evaluate the effects of functional, probiotic, prebiotic, or symbiotic food supplementation on mineral composition, histomorphometry, and bone biomechanical properties of rats in the growth phase, chronically exposed to cigarette smoke (T).Sixty-four young male rats were randomly assigned to eight groups (n=8): control (C) [standard diet (SD)]; probiotic (Pro) [SD + probiotic (Lactobacillus acidophilus, Enterococcus faecium, Bifidobacterium thermophilum and Bifidobacterium longum) (2-5 109 UFC each)]; prebiotic (Pre) [SD+ prebiotic (mannan oligosaccharide)]; symbiotic (Sym) (SD + probiotic + prebiotic); control smoking (SC) [(SD + exposure protocol to passive smoking (PS)]; probiotic smoking (ProS) (SD + probiotic + PS); prebiotic smoking (PreS) (SD + prebiotic + PS), and symbiotic smoking (SymS)(SD + prebiotic + probiotic + PS). The animals were euthanized after 189 days of the experimental protocol. Results showed that supplementation with probiotics, prebiotics, and symbiotics significantly improved (P<0.05) the parameters: P, Ca, Mg, BMD, BMC, strength, resilience, and size of area of the femoral diaphysis of the animals chronically exposed or not cigarette smoke. We concluded that functional food supplementation improved the bone health of rats chronically exposed or not to cigarette smoke.


RESUMO: A fumaça de cigarro em grandes centros é uma das causas mais importantes de doenças inflamatórias crônicas em saúde pública e esta associada à diminuição de massa óssea, processo de consolidação e remodelação óssea. Os alimentos funcionais suplementados na dieta, devido sua capacidade de melhorar a absorção intestinal e competir com microrganismos patógenos, podem contribuir para a melhora da qualidade óssea. Portanto, o objetivo desse estudo foi avaliar os efeitos da suplementação de alimentos funcionais, probiótico, prebiótico ou simbiótico, na composição mineral, histomorfometria e nas propriedades biomecânicas ósseas de ratos em fase de crescimento expostos cronicamente a fumaça do cigarro (T). Sessenta e quatro ratos machos jovens foram randomicamente distribuídos em oito grupos (n=8): controle (C) [dieta basal (DB)]; probiótico (Pro) [DB + probiótico (Lactobacillus acidophilus, Enterecoccusfaecium, Bifidobacterium thermophilumandBifidobacterium longum (2-5 109 UFC cada)]; prebiótico (Pre) [DB + prebiótico (mananoligossacarídeo)]; simbiótico (Sym) (DB + probiótico + prebiótico); controle fumante (CS) [(DB + protocolo de exposição ao tabagismo passivo(PT)]; probiótico fumante (ProS) (DB + probiótico + PT); prebiótico fumante (PreS) (DB + prebiótico + PT); e simbiótico fumante (SymS) (DB + prebiótico + probiótico + PT). Os animais foram mortos após 189 dias de período experimental.Os resultados revelaram que a suplementação com probióticos, prebióticos e simbióticos melhoraram significativamente (P<0,05) os parâmetros: P, Ca, Mg, DMO, CMO, resistência, resiliência e tamanho da área das diáfises dos fêmures dos animais expostos, cronicamente ou não, a fumaça do cigarro. Os resultados permitem concluir que a suplementação dos alimentos funcionais melhorou a saúde óssea de ratos expostos cronicamente ou não a fumaça do cigarro.

8.
Int. j. morphol ; 37(1): 104-110, 2019. graf
Artigo em Inglês | LILACS | ID: biblio-990013

RESUMO

SUMMARY: The objective of this study was to evaluate the effects of growth hormone (GH) and muscle strength training (ST) on the composition of bone tissue of Wistar rats through Raman spectroscopy. In total, 40 male rats were randomly distributed into four groups: (N = 10) control (C), control with the application of GH (GHC), strength training (T), and strength training with the application of GH (GHT). The training consisted of four series of 10 water jumps, performed three times a week, with an overload corresponding to 50 % of body weight and duration of four weeks. GH was applied at a dose of 0.2 IU / kg in each animal three times a week and every other day. After four weeks, the animals were euthanized and the right femurs collected for analysis of the bone structure. Raman spectroscopy (ER) was used to observe the following compounds from their respective bands: Calcium Carbonate-Triglycerides (fatty acids) 1073 cm-1, Collagen type I 509 cm-1, Bone-DNA Phosphate (Protein) 589 cm-1, Phosphate Phospholipids 1078 cm-1. For the statistical analysis, the Shapiro-Wilk and ANOVA One-Way variance analysis normality tests were performed, followed by the Tukey post-test. The results showed an increase in the concentrations of calcium carbonate-triglycerides (fatty acids), type I collagen, bone phosphate-DNA (protein), and phosphate phospholipids in all experimental groups, with or without ST and/or GH , But only the isolated training group differed significantly from the control group (P <0.05). It was concluded that all treatments could promote bone tissue gain, however, only the T group demonstrated a significant difference in the mineral compounds analyzed.


RESUMEN: El objetivo del estudio fue avaluar el efecto de la aplicación de la hormona del crecimiento (GH) y entrenamiento de la fuerza muscular (EF) en la composición del tejido óseo de ratas Wistar a partir de la espectroscopía Raman. Fueron utilizadas 40 ratas machos distribuidas de forma aleatoria en cuatro grupos (n=10): control (C), control y aplicación de GH (GHC), entrenamiento de la fuerza muscular (EF) y entrenamiento de la fuerza muscular y aplicación del GH (GHE). El entrenamiento fue consistió en cuatro series de 10 saltos acuáticos, realizados tres veces en la semana, con sobrecarga correspondiente a 50 % de la masa corporal y durante cuatro semanas. El GH fue aplicado en la dosificación de 0,2 UI/kg en cada animal, tres veces en la semana y en días alternados. Después de cuatro semanas, los animales fueran eutanasiados y retirados los fémures derechos para un análisis de la estructura ósea. La espectroscopía Raman fue utilizada para observar los siguientes compuestos a partir de las respectivas bandas: Carbonato de Calcio-Triglicéridos (ácidos grasos) 1073 cm-1, Colágeno Tipo I 509 cm-1, Fosfato Óseo-DNA (Proteína) 589 cm1, Fosfato Fosfolípidos 1078 cm-1. Para el análisis estadístico, fueron realizadas las pruebas Shapiro-Wilk y el análisis de variancia ANOVA One-Way, seguida de test post hoc de Tukey. Los resultados revelaran aumento de la concentración de Carbonato de Calcio-Triglicéridos (ácidos grasos), Colágeno Tipo I, Fosfato Óseo- DNA (Proteína), Fosfato Fosfolípidos en todos los grupos experimentales, asociados o no a la realización del EF y/o aplicación del GH. Además, solamente el grupo EF mostró diferencia significativa del grupo C (p<0,05). Es posible concluir que todos los tratamientos mostraran aumentos en el tejido óseo, sin embargo, solamente el grupo T demostró una diferencia significativa en los compuestos minerales analizados.


Assuntos
Animais , Masculino , Ratos , Natação/fisiologia , Osso e Ossos/química , Força Muscular/fisiologia , Fosfatos/análise , Análise Espectral Raman , Peso Corporal , Osso e Ossos/efeitos dos fármacos , Carbonato de Cálcio/análise , Hormônio do Crescimento/administração & dosagem , Exercício Físico/fisiologia , Densidade Óssea , Análise de Variância , Colágeno/análise , Ratos Wistar
10.
J Sci Food Agric ; 96(12): 3977-82, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26997541

RESUMO

Chromium is a common mineral in the earth's crust and can be released into the environment from anthropogenic sources. Intake of hexavalent chromium (Cr(VI)) through drinking water and food causes toxic effects, leading to serious diseases, and is a commonly reported environmental problem. Microorganisms can mitigate or prevent the toxic effects caused by heavy metals in addition to having effective resistance mechanisms to prevent cell damage and bind to these metals, sequestering them from the cell surface and removing them from the body. Species of Lactobacillus, Streptococcus, Bacillus and Bifidobacterium present in the human mouth and gut and in fermented foods have the ability to bind and detoxify some of these substances. This review address the primary topics related to Cr(VI) poisoning in animals and humans and the use of probiotics as a way to mitigate or prevent the toxic effects caused by Cr(VI). Further advances in the genetic knowledge of such microorganisms may lead to discoveries which will clarify the most active microorganisms that act as bioprotectants in bodies exposed to Cr(VI) and are an affordable option for people and animals intoxicated by the oral route. © 2016 Society of Chemical Industry.


Assuntos
Bactérias/metabolismo , Cromo/metabolismo , Trato Gastrointestinal/microbiologia , Metais Pesados/metabolismo , Probióticos , Animais , Cromo/toxicidade , Contaminação de Alimentos , Humanos , Metais Pesados/toxicidade
11.
Histol Histopathol ; 30(1): 61-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24957214

RESUMO

Cadmium is a heavy metal that is widely used in industry and can cause tumours in multiple organs. The purpose of our study was to investigate the effect of water pH in the genesis of cadmium-induced cancer. We divided 98 male Wistar rats into 7 groups: group A - 15 rats that received cadmium chloride (CdCl2- 400 mg/L) in their drinking water at a neutral pH of 7.0; group B - 15 rats that received CdCl2(400 mg/L) in their drinking water at an acidic pH of 5.0; group C - 15 rats that received CdCl2(400 mg/L) in their drinking water at a basic pH of 8.0; group D - 15 rats that received water at an acidic pH of 5.0; group E - 15 rats that received water at a basic pH of 8.0; group F - 15 rats that received water at a neutral pH of 7.0; and group G - 8 rats that were subcutaneously injected with a single dose of cyclophosphamide (50 mg/kg). Groups A through F were euthanised 6 months after the start of the experiment and group G was euthanised 24 hours after cyclophosphamide injection. We collected the liver, kidneys, pancreas, prostate, seminal vesicles and testes for histopathological analysis and the bone marrow for micronuclei testing. In all of the groups, neither neoplastic lesions nor an increase in micronuclei (p>0.05) were observed in the liver, kidney, pancreas, seminal vesicles and testes. We found that animals exposed to cadmium had grade one prostatic intraepithelial neoplasia, but this was found more frequently in animals from group B (p<0.05). The acidic pH increased the formation of pre-neoplastic lesions in the prostate glands of cadmium-exposed animals.


Assuntos
Cloreto de Cádmio/toxicidade , Próstata/efeitos dos fármacos , Neoplasias da Próstata/induzido quimicamente , Microambiente Tumoral/efeitos dos fármacos , Água , Animais , Concentração de Íons de Hidrogênio , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Próstata/patologia , Neoplasias da Próstata/patologia , Ratos , Ratos Wistar , Glândulas Seminais/efeitos dos fármacos , Glândulas Seminais/patologia , Testículo/efeitos dos fármacos , Testículo/patologia
12.
Int. j. morphol ; 25(3): 631-638, Sept. 2007. ilus, tab
Artigo em Inglês | LILACS | ID: lil-626916

RESUMO

We investigated the effect of swimming training in rats on morphological characteristics, hypertrophy levels and metabolic and contractile adaptations of different fiber types in rat the rectus abdominis muscle. Rats were randoverly assigned to one of three groups (N = 5 each): a) swimming training for 1 h, twice a week (2x/w), b) 1 h five times a week (5x/w) for 9 consecutive weeks, or c) without any swimming training (Control). Body weight increased in 2x/w rats and decreased in the 5x/w ones. Muscle fiber diameters increased in both trained groups, with higher values in the 2x/w group. Aerobic exercise increased slow oxidative (SO) + fast-oxidative-glycolytic (FOG) fibers and decreased fast glycolytic (FG) fibers. In addition, SO fibers were increased and FOG + FG fibers were decreased in trained rats. Small and angulated atrophic fibers were also observed. These results corroborate that swimming exercise increases aerobic metabolism and thus oxidative and low contraction fibers. However, the used protocol induced, to a variable degree, changes in the muscle fiber morphology.


Se estudió el efecto de la natación en las características morfológicas, niveles de hipertrofia y las adaptaciones metabólicas y contráctiles de diferentes tipos de fibras en el músculo recto del abdomen de ratas. Las ratas fueron asignadas en tres grupos (N = 5 cada uno): a) natación por 1 hora dos veces a la semana (2x/s), b) 1 hora, cinco veces por semana (5x/s) por nueve semanas consecutivas y c) sin natación (control). El peso corporal se incrementó en las ratas 2x/s y disminuyó en 5x/s. El diámetro de las fibras musculares aumentó en ambos grupos entrenados, con mayores valores en las ratas 2x/s. El ejercicio aeróbico incrementó las fibras de oxidación lenta (OL) + las fibras de glicólisis oxidativa rápida (GOR) y disminuyeron las fibras de glicólisis rápida (GR). Además, las fibras OL aumentaron y las fibras GOR y GR disminuyeron en las ratas entrenadas. Se observó una pequeña atrofia y deshidratación de las fibras. Estos resultados corroboran que la práctica de la natación incrementa el metabolismo aeróbico, las fibras de contracción lenta y la oxidación. Sin embargo, el protocolo utilizado induce cambios en grado variable en la morfología de las fibras musculares.


Assuntos
Animais , Ratos , Natação , Exercício Físico , Reto do Abdome/anatomia & histologia , Músculos Abdominais/anatomia & histologia , Fibras Musculares Esqueléticas , Histocitoquímica
13.
Ciênc. rural ; 35(3): 691-697, maio-jun. 2005. tab
Artigo em Português | LILACS | ID: lil-400575

RESUMO

O objetivo deste estudo foi ajustar o método espectrofotométrico da 1,5-difenilcarbazida à determinação do crômio em fezes, como marcador biológico, adequando-o à rotina laboratorial. Fatores que poderiam exercer interferência na transformação do crômio (III) à crômio (VI) foram testados, como a recuperação do metal, quantidade de amostra, quantidade e ordem de emprego dos ácidos oxidantes da digestão úmida, temperatura e tempo de digestão e perda por volatilização do crômio como cloreto de cromila, porém não se determinou estatisticamente interferência destes fatores. No método ajustado, a amostra é digerida pela clássica mistura ácida nítrica/perclórica, levando a oxidação do crômio (III) a crômio (VI), e alíquota do extrato diluído é usado para reação com 1,5-difenilcarbazida; as absorbâncias são medidas a 550nm, utilizando-se de cubetas de um centímetro de caminho óptico, contra prova em branco conduzida simultaneamente. Dicromato de potássio foi empregado como substância de referência para obtenção da curva padrão na faixa de 0,25 - 2,5mg.mL-1 de Cr2O3 (1mg Cr2O3 º 1,9355mg K2Cr2O7).

14.
Ciênc. rural ; 34(5): 1501-1504, set.-out. 2004. tab
Artigo em Português | LILACS | ID: lil-383596

RESUMO

Com o objetivo de estudar as concentrações de zinco da sola do casco de bovinos com e sem lesões podais, suplementados ou não com levedura seca, foram selecionadas e examinadas 60 vacas, escolhidas aleatoriamente, de um rebanho de 150 animais. Formaram-se quatro grupos de 15 animais, sendo o primeiro com animais com lesões podais e suplementados com levedura, o segundo com animais com lesões podais e sem suplementação de levedura, o terceiro com animais sem lesões podais e suplementados com levedura e o quarto com animais sem lesões podais e sem a suplementação de levedura. As concentrações de zinco da sola do casco foram determinadas por espectrometria de absorção atômica com chama (AAS). A comparação estatística das concentrações de zinco nas amostras foram submetidos à análise de variância, seguida pelo teste de Tukey, para comparação de médias. As médias das concentrações de zinco da sola do casco dos animais dos quatro grupos, quando comparadas estatisticamente, apresentaram diferença estatística significativa, somente nos animais com lesões podais e suplementados com levedura.

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