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1.
Braz J Med Biol Res ; 54(6): e10293, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33909854

RESUMO

The skin injury healing process involves the main phases of homoeostasis, inflammation, proliferation, and remodeling. The present study aimed to analyze the effects of low-level laser therapy (LLLT) on hematological dynamics, oxidative stress markers, and its relation with tissue healing following skin injury. Wistar rats were divided into control, sham, skin injury, and skin injury LLLT. The biochemical and morphological analyses were performed in the inflammatory (1 and 3 days) and regenerative phases (7, 14, and 21 days) following injury. The skin injury was performed in the dorsal region, between the intrascapular lines, using a surgical punch. LLLT (Al-Ga-In-P, λ=660 nm, energy density of 20 J/cm2, 30 mW power, and a time of 40 s) was applied at the area immediately after injury and on every following day according to the experimental subgroups. LLLT maintained hematocrit and hemoglobin levels until the 3rd day of treatment. Surprisingly, LLLT increased total leukocytes levels compared to control until the 3rd day. The effects of LLLT on mitochondrial activity were demonstrated by the significant increase in MTT levels in both inflammatory and regenerative phases (from the 1st to the 7th day), but only when associated with skin injury. The results indicated that LLLT modulated the inflammatory response intensity and accelerated skin tissue healing by a mechanism that involved oxidative damage reduction mostly at early stages of skin healing (inflammatory phase).


Assuntos
Terapia a Laser , Terapia com Luz de Baixa Intensidade , Animais , Estresse Oxidativo , Ratos , Ratos Wistar , Cicatrização
2.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;54(6): e10293, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1249308

RESUMO

The skin injury healing process involves the main phases of homoeostasis, inflammation, proliferation, and remodeling. The present study aimed to analyze the effects of low-level laser therapy (LLLT) on hematological dynamics, oxidative stress markers, and its relation with tissue healing following skin injury. Wistar rats were divided into control, sham, skin injury, and skin injury LLLT. The biochemical and morphological analyses were performed in the inflammatory (1 and 3 days) and regenerative phases (7, 14, and 21 days) following injury. The skin injury was performed in the dorsal region, between the intrascapular lines, using a surgical punch. LLLT (Al-Ga-In-P, λ=660 nm, energy density of 20 J/cm2, 30 mW power, and a time of 40 s) was applied at the area immediately after injury and on every following day according to the experimental subgroups. LLLT maintained hematocrit and hemoglobin levels until the 3rd day of treatment. Surprisingly, LLLT increased total leukocytes levels compared to control until the 3rd day. The effects of LLLT on mitochondrial activity were demonstrated by the significant increase in MTT levels in both inflammatory and regenerative phases (from the 1st to the 7th day), but only when associated with skin injury. The results indicated that LLLT modulated the inflammatory response intensity and accelerated skin tissue healing by a mechanism that involved oxidative damage reduction mostly at early stages of skin healing (inflammatory phase).


Assuntos
Animais , Ratos , Terapia com Luz de Baixa Intensidade , Terapia a Laser , Cicatrização , Ratos Wistar , Estresse Oxidativo
3.
Braz J Med Biol Res ; 51(11): e7702, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30304134

RESUMO

When exercises are done in intense or exhaustive modes, several acute biochemical mechanisms are triggered. The use of cryotherapy as cold-water immersion is largely used to accelerate the process of muscular recovery based on its anti-inflammatory and analgesic properties. The present study aimed to study the biochemical effects of cold-water immersion treatment in mice submitted to exercise-induced exhaustion. Swiss albino mice were divided into 4 treatment groups: control, cold-water immersion (CWI), swimming exhaustive protocol (SEP), and SEP+CWI. Treatment groups were subdivided into times of analysis: 0, 1, 3, and 5 days. Exhaustion groups were submitted to one SEP session, and the CWI groups submitted to one immersion session (12 min at 12°C) every 24 h. Reactive species production, inflammatory, cell viability, and antioxidant status were assessed. The SEP+CWI group showed a decrease in inflammatory damage biomarkers, and reactive species production, and presented increased cell viability compared to the SEP group. Furthermore, CWI increased acetylcholinesterase activity in the first two sessions. The present study showed that CWI was an effective treatment after exercise-induced muscle damage. It enhanced anti-inflammatory response, decreased reactive species production, increased cell viability, and promoted redox balance, which could decrease the time for the recovery process.


Assuntos
Crioterapia/métodos , Imersão/fisiopatologia , Músculo Esquelético/lesões , Músculo Esquelético/fisiopatologia , Condicionamento Físico Animal/efeitos adversos , Condicionamento Físico Animal/fisiologia , Natação/fisiologia , Acetilcolinesterase/análise , Animais , Antioxidantes/análise , Sobrevivência Celular/fisiologia , Temperatura Baixa , Fluoresceínas/análise , Masculino , Camundongos , Miosite/prevenção & controle , Espécies Reativas de Oxigênio/análise , Reprodutibilidade dos Testes , Natação/lesões , Sais de Tetrazólio , Tiazóis , Fatores de Tempo , Resultado do Tratamento , Água/fisiologia
4.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;51(11): e7702, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-951726

RESUMO

When exercises are done in intense or exhaustive modes, several acute biochemical mechanisms are triggered. The use of cryotherapy as cold-water immersion is largely used to accelerate the process of muscular recovery based on its anti-inflammatory and analgesic properties. The present study aimed to study the biochemical effects of cold-water immersion treatment in mice submitted to exercise-induced exhaustion. Swiss albino mice were divided into 4 treatment groups: control, cold-water immersion (CWI), swimming exhaustive protocol (SEP), and SEP+CWI. Treatment groups were subdivided into times of analysis: 0, 1, 3, and 5 days. Exhaustion groups were submitted to one SEP session, and the CWI groups submitted to one immersion session (12 min at 12°C) every 24 h. Reactive species production, inflammatory, cell viability, and antioxidant status were assessed. The SEP+CWI group showed a decrease in inflammatory damage biomarkers, and reactive species production, and presented increased cell viability compared to the SEP group. Furthermore, CWI increased acetylcholinesterase activity in the first two sessions. The present study showed that CWI was an effective treatment after exercise-induced muscle damage. It enhanced anti-inflammatory response, decreased reactive species production, increased cell viability, and promoted redox balance, which could decrease the time for the recovery process.


Assuntos
Animais , Masculino , Coelhos , Condicionamento Físico Animal/efeitos adversos , Condicionamento Físico Animal/fisiologia , Crioterapia/métodos , Músculo Esquelético/fisiopatologia , Músculo Esquelético/lesões , Imersão/fisiopatologia , Acetilcolinesterase/análise , Natação/lesões , Tiazóis , Fatores de Tempo , Sobrevivência Celular/fisiologia , Reprodutibilidade dos Testes , Espécies Reativas de Oxigênio/análise , Temperatura Baixa , Fluoresceínas/análise , Miosite/prevenção & controle , Antioxidantes/análise
5.
Braz. J. Biol. ; 74(4): 828-836, 11/2014. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-13437

RESUMO

In this study, we hypothesized that the life history traits of Leiothrix spiralis and L. vivipara would be linked to soil factors of the rupestrian grasslands and that rosette size would be influenced by soil moisture. Soil analyses were performed from five populations of L. spiralis and four populations of L. vivipara. In each area, three replicates were employed in 19 areas of occurrence of Leiothrix species, and we quantified the life history attributes. The microhabitats of these species show low favorability regarding to soil factors. During the dry season, their rosettes decreased in diameter due the loss of its most outlying leaves. The absence of seedlings indicated the low fecundity of both species. However, both species showed rapid population growth by pseudovivipary. Both L. spiralis and L. vivipara exhibit a kind of parental care that was quantified by the presence of connections between parental-rosettes and ramets. The findings of the present study show that the life history traits are linked to soil factors.(AU)


Neste estudo, testamos a hipótese de que os traços da história de vida de Leiothrix spiralis e L.vivipara estariam ligados a fatores do solo dos campos rupestres, e que o tamanho de roseta seria influenciado pela umidade do solo. As análises de solo foram realizadas a partir de cinco populações de L. spiralis e quatro populações de L. vivipara. Em cada área, três repetições foram empregadas em 19 áreas de ocorrência das espécies de Leiothrix, e quantificamos os atributos de história de vida. Os microhabitats destas espécies apresentam baixa “favorabilidade” em relação aos fatores de solo. Durante a estação seca, as rosetas diminuíram de diâmetro devido à perda de suas folhas mais periféricas. A ausência de plântulas indicou a baixa fecundidade de ambas as espécies. No entanto, ambas as espécies apresentaram crescimento rápido da população por pseudoviviparidade. Tanto L. spiralis quanto L. vivipara exibem um tipo de cuidado parental que foi quantificada pela presença de conexões entre rosetas parentais e rametes. Os resultados do presente estudo mostram que os traços da história de vida estão ligados aos fatores do solo.(AU)


Assuntos
Eriocaulaceae/crescimento & desenvolvimento , Solo , Brasil , Eriocaulaceae/classificação , Umidade , Estações do Ano
6.
Braz J Biol ; 74(4): 828-36, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25627592

RESUMO

In this study, we hypothesized that the life history traits of Leiothrix spiralis and L. vivipara would be linked to soil factors of the rupestrian grasslands and that rosette size would be influenced by soil moisture. Soil analyses were performed from five populations of L. spiralis and four populations of L. vivipara. In each area, three replicates were employed in 19 areas of occurrence of Leiothrix species, and we quantified the life history attributes. The microhabitats of these species show low favorability regarding to soil factors. During the dry season, their rosettes decreased in diameter due the loss of its most outlying leaves. The absence of seedlings indicated the low fecundity of both species. However, both species showed rapid population growth by pseudovivipary. Both L. spiralis and L. vivipara exhibit a kind of parental care that was quantified by the presence of connections between parental-rosettes and ramets. The findings of the present study show that the life history traits are linked to soil factors.


Assuntos
Eriocaulaceae/crescimento & desenvolvimento , Solo , Brasil , Eriocaulaceae/classificação , Umidade , Estações do Ano
7.
Braz. J. Biol. ; 73(4): 699-708, Nov. 2013. mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-30976

RESUMO

Rhinodrilus alatus is an endemic giant earthworm of the Brazilian Cerrado hotspot used as live bait for about 80 years. The goal of this study was to gather ecological data about this species, which will support the establishment of management strategies. The life history, distribution and abundance of R. alatus were investigated in Cerrado, pastures and Eucalyptus plantation areas following the harvesting activities of the local extractors of this species. We found that this earthworm is abundant in all of the sampled areas, showing its resilience to land-use conversion. The Capture Per Unit Effort was 4.4 ± 5 individuals per 100 metres of transect and 5.6 ± 3 individuals per hour. The earthworm's annual cycle is markedly seasonal, with an aestivation period throughout the driest and coldest season of the year. Significant differences in the length and diameter of the body and in the diameter and depth of the aestivation chambers were found between the juveniles and adults. The distribution range of the species was expanded from two to 17 counties. The life history, abundance, distribution and resilience of R. alatus to certain perturbations are key elements to be considered in conservation and management strategies for this species.(AU)


Rhinodrilus alatus é um minhocuçu endêmico do hotspot Cerrado, utilizado como isca viva por cerca de 80 anos. O objetivo deste estudo foi obter informações ecológicas sobre essa espécie, as quais servirão para o estabelecimento de estratégias para seu manejo. A história de vida, a distribuição e a abundância de R. alatus foram investigados em áreas de Cerrado, pastagens e plantações de Eucalyptus, acompanhando sua extração pela comunidade local. Rhinodrilus alatus foi abundante em todas as áreas amostradas, mostrando-se resiliente à conversão do Cerrado em outros usos. A Captura por Unidade de Esforço foi de 4.4 ± 5 indivíduos por 100 metros de transecto e 5.6 ± 3 indivíduos por hora. O ciclo anual do minhocuçu é marcadamente sazonal, apresentando estivação no período mais frio e seco do ano. Jovens e adultos diferiram significativamente no comprimento e diâmetro do corpo e no diâmetro e profundidade da câmara de estivação. A distribuição da espécie foi expandida de dois para 17 municípios. A história de vida, a abundância, a distribuição e resiliência de R. alatus por certos distúrbios são elementos chave a serem considerados nas estratégias de conservação e manejo dessa espécie.(AU)


Assuntos
Animais , Oligoquetos/fisiologia , Oligoquetos/anatomia & histologia , Conservação dos Recursos Naturais , Pradaria , Brasil
8.
Braz J Biol ; 73(4): 699-708, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24789384

RESUMO

Rhinodrilus alatus is an endemic giant earthworm of the Brazilian Cerrado hotspot used as live bait for about 80 years. The goal of this study was to gather ecological data about this species, which will support the establishment of management strategies. The life history, distribution and abundance of R. alatus were investigated in Cerrado, pastures and Eucalyptus plantation areas following the harvesting activities of the local extractors of this species. We found that this earthworm is abundant in all of the sampled areas, showing its resilience to land-use conversion. The Capture Per Unit Effort was 4.4 ± 5 individuals per 100 metres of transect and 5.6 ± 3 individuals per hour. The earthworm's annual cycle is markedly seasonal, with an aestivation period throughout the driest and coldest season of the year. Significant differences in the length and diameter of the body and in the diameter and depth of the aestivation chambers were found between the juveniles and adults. The distribution range of the species was expanded from two to 17 counties. The life history, abundance, distribution and resilience of R. alatus to certain perturbations are key elements to be considered in conservation and management strategies for this species.


Assuntos
Estágios do Ciclo de Vida , Oligoquetos/anatomia & histologia , Oligoquetos/classificação , Animais , Brasil , Oligoquetos/crescimento & desenvolvimento , Densidade Demográfica , Dinâmica Populacional , Estações do Ano
9.
Orthod Craniofac Res ; 13(1): 48-55, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20078795

RESUMO

OBJECTIVES: Evaluate the shear bond strength (SBS) and the adhesive remnant index (ARI) of indirect bonded lingual brackets using xenon plasma arc light, light-emitting diode (LED) and conventional quartz-tungsten-halogen light. MATERIAL AND METHODS: Lingual brackets were bonded indirectly to 60 premolars divided to three groups according to the curing light used: Group 1, plasma arc for 6 s; Group 2, LED for 10 s; and Group 3, halogen light for 40 s. After bonding, the specimens were subjected to a shear force until debonding. The debonding pattern was assessed and classified according to the ARI scores. The mean shear bond strengths were accessed by anova followed by the Student-Newman-Keuls test for multiple comparisons. ARI scores were assessed using the chi-square test. RESULTS: The three groups showed significant differences (p < 0.001), with the averages of group 1 < group 2 < group 3. Groups showed no differences regarding ARI scores. CONCLUSION: Bonding lingual brackets indirectly with plasma arc, during 60% of the time used for the LED, produced lower SBS than obtained with the latter. Using LED during 25% of the time of the halogen light produced lower SBS than obtained with the latter. These differences did not influence the debonding pattern and are clinically acceptable according to the literature.


Assuntos
Lâmpadas de Polimerização Dentária , Cura Luminosa de Adesivos Dentários , Braquetes Ortodônticos , Análise do Estresse Dentário , Humanos , Resistência ao Cisalhamento
10.
Braz J Biol ; 66(2A): 463-71, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16862301

RESUMO

Species of plants used by Melipona quadrifasciata Lepeletier for pollen and nectar gathering in an urban forest fragment were recorded in Belo Horizonte, Minas Gerais, Brazil. Melipona quadrifasciata visited 22 out of 103 flowering plant species. The plant species belonged mainly to Myrtaceae, Asteraceae, and Convolvulaceae (64% of the visits). Melipona quadrifasciata tended to collect pollen or nectar each time, except for Myrtaceae species, from which both pollen and nectar were collected. Bee abundance at flowers did not significantly correlate to food availability (expressed by flowering plant richness). We found a relatively high similarity (50%) between plant species used by M. quadrifasciata, which was also found in studies carried out in São Paulo State. However, low similarity (17%) was found between the results of this study and those of another done in Bahia State, Brazil.


Assuntos
Abelhas/fisiologia , Flores/classificação , Animais , Comportamento Alimentar/fisiologia , Estações do Ano , Árvores , Clima Tropical
11.
Braz. j. biol ; Braz. j. biol;66(2a): 463-471, May 2006. tab, graf
Artigo em Inglês | LILACS | ID: lil-431534

RESUMO

Inventariaram-se as espécies de plantas utilizadas por Melipona quadrifasciata Lepeletier, para coletar pólen e néctar. Melipona quadrifasciata visitou 22 das 103 espécies de plantas floridas durante o período de estudo. Sessenta e quatro por cento das visitas foram principalmente em Myrtaceae, Asteraceae e Convolvulaceae. Melipona quadrifasciata tende a coletar apenas pólen e néctar nas suas visitas, exceto em Myrtaceae onde ambos os recursos foram coletados. A abundância de abelhas nas flores não se correlacionou com a disponibilidade de recursos (expressa pela riqueza de plantas floridas). Houve uma similaridade relativamente alta (50%) entre as espécies de plantas visitadas por M. quadrifasciata nesse estudo e outro desenvolvido em São Paulo. Uma baixa similaridade (17%) na utilização dos recursos foi verificada entre este estudo e outro conduzido na Bahia.


Assuntos
Animais , Abelhas/fisiologia , Flores/classificação , Comportamento Alimentar/fisiologia , Estações do Ano , Árvores , Clima Tropical
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