Low-power infrared laser modulates mRNA levels from genes of base excision repair and genomic stabilization in heart tissue from an experimental model of acute lung injury.

The aim of this study was to evaluate photobiomodulation effects on mRNA relative levels from genes of base excision repair and genomic stabilization in heart tissue from an experimental model of acute lung injury by sepsis. For experimental procedure, animals were randomly assigned to six main groups: (1) control group was animals treated with intraperitoneal saline solution; (2) LASER-10 was animals treated with intraperitoneal saline solution and exposed to an infrared laser at 10 J cm-2; (3) LASER-20 was animals treated with intraperitoneal saline solution and exposed to an infrared laser at 20 J cm-2; (4) acute lung injury (ALI) was animals treated with intraperitoneal LPS (10 mg kg-1); (5) ALI-LASER10 was animals treated with intraperitoneal LPS (10 mg kg-1) and, after 4 h, exposed to an infrared laser at 10 J cm-2 and (6) ALI-LASER20 was animals treated with intraperitoneal LPS (10 mg kg-1) and, after 4 h, exposed to an infrared laser at 20 J cm-2. Irradiation was performed only once and animal euthanasias for analysis of mRNA relative levels by RT-qPCR. Our results showed that there was a reduction of mRNA relative levels from ATM gene and an increase of mRNA relative levels from P53 gene in the heart of animals with ALI when compared to the control group. In addition, there was an increase of mRNA relative levels from OGG1 and APE1 gene in hearts from animals with ALI when compared to the control group. After irradiation, an increase of mRNA relative levels from ATM and OGG1 gene was observed at 20 J cm-2. In conclusion, low-power laser modulates the mRNA relative levels from genes of base excision repair and genomic stabilization in the experimental model of acute lung injury evaluated.

Low-power infrared laser modulates telomere length in heart tissue from an experimental model of acute lung injury.

Acute lung injury and acute respiratory distress syndrome can occur as a result of sepsis. Cardiac dysfunction is a serious component of multi-organ failure caused by severe sepsis. Telomere shortening is related to several heart diseases. Telomeres are associated with the shelterin protein complex, which contributes to the maintenance of telomere length. Low-power infrared lasers modulate mRNA levels of shelterin complex genes. This study aimed to evaluate effects of a low-power infrared laser on mRNA relative levels of genes involved in telomere stabilization and telomere length in heart tissue of an experimental model of acute lung injury caused by sepsis. Animals were divided into six groups, treated with intraperitoneal saline solution, saline solution and exposed to a low-power infrared laser at 10 J cm-2 and 20 J cm-2, lipopolysaccharide (LPS), and LPS and, after 4 h, exposed to a low-power infrared laser at 10 J cm-2 and 20 J cm-2. The laser exposure was performed only once. Analysis of mRNA relative levels and telomere length by RT-qPCR was performed. Telomere shortening and reduction in mRNA relative levels of TRF1 mRNA in heart tissues of LPS-induced ALI animals were observed. In addition, laser exposure increased the telomere length at 10 J cm-2 and modulated the TRF1 mRNA relative levels of at 20 J cm-2 in healthy animals. Although the telomeres were shortened and mRNA levels of TRF1 gene were increased in nontreated controls, the low-power infrared laser irradiation increased the telomere length at 10 J cm-2 in cardiac tissue of animals affected by LPS-induced acute lung injury, which suggests that telomere maintenance is a part of the photobiomodulation effect induced by infrared radiation.

Effect of low power lasers on prokaryotic and eukaryotic cells under different stress condition: a review of the literature.

Radiations emitted by low power radiation sources have been applied for therapeutic proposals due to their capacity of inactivating bacteria and cancer cells in photodynamic therapy and stimulating tissue cells in photobiomodulation. Exposure to these radiations could increase cell proliferation in bacterial cultures under stressful conditions. Cells in infected or not infected tissue injuries are also under stressful conditions and photobiomodulation-induced regenerative effect on tissue injuries could be related to effects on stressed cells. The understanding of the effects on cells under stressful conditions could render therapies based on photobiomodulation more efficient as well as expand them. Thus, the objective of this review was to update the studies reporting photobiomodulation on prokaryotic and eukaryotic cells under stress conditions. Exposure to radiations emitted by low power radiation sources could induce adaptive responses enabling cells to survive in stressful conditions, such as those experienced by bacteria in their host and by eukaryotic cells in injured tissues. Adaptive responses could be the basis for clinical photobiomodulation applications, either considering their contraindication for treatment of infected injuries or indication for treatment of injuries, inflammatory process resolution, or tissue regeneration.

A caracterização da gestão da rede de atenção à saúde bucal no estado do Rio de Janeiro pelo perfil regional / The characterization of the management of the oral health care network in the state of Rio de Janeiro by the regional profile

Resumo A Rede de Atenção à Saúde Bucal (RASB) é constituída por três elementos: a população, a estrutura e o modelo de atenção à saúde. As ações dessa rede são distribuídas pelos pontos de atenção primário, secundário e terciário. O objetivo do texto consiste em conhecer o seu estágio de desenvolvimento na região serrana do estado do Rio de Janeiro e as maiores fragilidades. Constitui um estudo de casos, exploratório e transversal, com amostra intencional e aplicação de questionário estruturado. A interpretação dos dados foi realizada por meio da média dos pontos e pela análise de correlação de Pearson, que demonstrou o predomínio da RASB incipiente (∑ = 137 pontos) e a correlação forte das variáveis: adoção de protocolos clínicos X capacidade resolutiva da atenção secundária, manutenção dos equipamentos odontológicos X existência de laboratórios de apoio, existência de ações educativas X frequência de sua utilização, frequência de sua utilização X ações reabilitadoras para o câncer bucal, as ações reabilitadoras para o câncer bucal X existência de um plano de cuidado (r≥0,90). Concluiu-se que a RASB encontra-se em estágio incipiente e as fragilidades envolvem dificuldades na adscrição, nos encaminhamentos, na emissão de laudos radiológicos, na adoção de prontuário eletrônico e na apropriação dos instrumentos de gestão.

Abstract The Oral Health Care Network (OHCN) consists of three elements: the population, the structure and the model of health care, and its actions distributed by the primary, secondary and tertiary care points. The objective is to know its stage of development in the highland region of the state of Rio de Janeiro and the biggest weaknesses. Exploratory and crosssectional case study with intentional sample and application of structured questionnaire. Data interpretation was performed by means of the points average and Pearson's correlation analysis, which demonstrated the predominance of incipient OHCN (∑ = 137 points) and the strong correlation of the variables: adoption of clinical protocols vs. secondary care resolution capacity. , maintenance of dental equipment X existence of support laboratories, existence of educational actions X frequency of its use, between frequency of its use X rehabilitation actions for oral cancer, among the rehabilitation actions for oral cancer X existence of a care plan (r≥0.90). It was concluded that the RASB is in an incipient stage and the weaknesses involve difficulties in the subscription, referrals, issuing radiological reports, the adoption of electronic medical records and the appropriation of management instruments.

Photobiomodulation by dual-wavelength low-power laser effects on infected pressure ulcers.

The aim of this study was to evaluate the effects of photobiomodulation (PBM) by dual-wavelength low-power lasers on the healing and bacterial bioburden of pressure ulcer (PU) models. Twenty-five male Swiss mice were divided into five equal groups. Ischemia reperfusion cycles were employed to cause PU formation by the external application of magnetic plates. Immediately after wounding, a suspension of Pantoea agglomerans was applied at the base of all the wounds of the infected groups, using a calibrated pipette. PBM (simultaneous emission at 660 and 808 nm, 142.8 J/cm2, in continuous wave emission mode) was applied to the PUs for 14 sessions. The animals were euthanized 14 days after PU induction, and their tissues were analyzed for wound contraction and reepithelialization, epidermis thickness, bacterial survival, and IL-1ß and IL-10 mRNA level evaluations. The PU areas appeared larger in the mice from the infected groups than in those in the laser group 4 days after PU induction and presented incomplete reepithelialization 14 days after PU induction. However, the PBM accelerated the wound healing in the infected + laser group compared with the infected group 11 and 14 days following the PU induction. The infected and irradiated PUs exhibited a thinner neo-epidermis than those in the infected group, and the bacterial survival decreased in the laser group; the relative expression IL-1ß mRNA levels demonstrated an increasing tendency while the relative expression IL-10 mRNA levels demonstrated a decreasing tendency in the infected + laser and laser groups. These results suggest that PBM improves healing by killing or inhibiting bacteria in PUs as well as by accelerating the wound healing, resulting in tissue repair.

Correction to: Photobiomodulation by dual-wavelength low-power laser effects on infected pressure ulcers.

The author name Maria Maria Côrtes Thomé Lima was incorrectly captured in the original article. The correct author name should be Andrezza Maria Côrtes Thomé Lima. The original article has been corrected.

Ultrassonografia diafragmática como ferramenta de avaliação no desmame da ventilação mecânica / Diaphragmatic ultrasound as assessment tool for mechanical ventilation weaning

A ultrassonografia é uma ferramenta diagnóstica muito utilizada na unidade de terapia intensiva devido ao baixo custo, por não ser um procedimento invasivo, de rápido aprendizado e oferecendo toda a gama de informações sobre diferentes órgãos e tecidos. Nos últimos anos, tem sido publicado um número crescente de artigos sobre a avaliação do diafragma. A ultrassonografia pode ser uma ferramenta útil para avaliar a disfunção diafragmática em pacientes críticos, porém, apesar de existir padronização da técnica e das variáveis analisadas, ainda não existe consenso sobre a utilização das medidas que podem ser influenciadas pelo posicionamento do transdutor, tipo de ventilação (espontânea ou mecânica controlada) e posição do paciente. Sendo assim, esta revisão reuniu os trabalhos mais atuais a fim de elucidarmos as formas de avaliação morfofuncional por ultrassonografia do diafragma pela comunidade científica e fornecer conhecimentos acerca dessa ferramenta. As variáveis ultrassonográficas mais utilizadas pelos autores encontradas nesta revisão foram: 1) a espessura diafragmática (ED); 2) a fração de espessamento diafragmática (FED); 3) a excursão diafragmática (ExD). A utilização do ultrassom na avaliação da disfunção e atrofia diafragmática em pacientes ventilados mecanicamente parece estar bem estabelecida na literatura, porém, o uso dessas três variáveis na predição de sucesso de desmame e extubação apresentam resultados inconclusivos. (AU)

Ultrasonography is an increasingly popular diagnostic tool in the intensive care unit because of its easy applicability, low cost, non-invasiveness, fast learning and delivering full range of information on different organs and tissues. In the recent years, an exponentially increasing number of articles has been published on diaphragm evaluation. Ultrasonography can be a useful tool to evaluate diaphragmatic dysfunction in critically ill patients. However, although the technique and variables analyzed are not standardized, there is still no consensus on the use of measures that can be influenced because the analysis may vary depending on the position of the transducer, the type of ventilation (spontaneous or mechanically controlled) and the position of the patient. Thus, this review brought together current works in order to elucidate the forms of morphologic and functional evaluation by diaphragm muscle ultrasonography in order to provide knowledge about this tool. The ultrasound variables most used by the authors were: 1) The diaphragmatic thickness; 2) The diaphragmatic thickening fraction; 3) The diaphragmatic excursion. The ultrasound tool in the evaluation of diaphragmatic dysfunction and atrophy in mechanically ventilated patients seems to be well established in the literature, but the use of these three variables in predicting successful weaning and extubation presents inconclusive results. (AU)

Photobiomodulation effects on mRNA levels from genomic and chromosome stabilization genes in injured muscle.

Muscle injuries are the most prevalent type of injury in sports. A great number of athletes have relapsed in muscle injuries not being treated properly. Photobiomodulation therapy is an inexpensive and safe technique with many benefits in muscle injury treatment. However, little has been explored about the infrared laser effects on DNA and telomeres in muscle injuries. Thus, the aim of this study was to evaluate photobiomodulation effects on mRNA relative levels from genes related to telomere and genomic stabilization in injured muscle. Wistar male rats were randomly divided into six groups: control, laser 25 mW, laser 75 mW, injury, injury laser 25 mW, and injury laser 75 mW. Photobiomodulation was performed with 904 nm, 3 J/cm2 at 25 or 75 mW. Cryoinjury was induced by two applications of a metal probe cooled in liquid nitrogen directly on the tibialis anterior muscle. After euthanasia, skeletal muscle samples were withdrawn and total RNA extracted for evaluation of mRNA levels from genomic (ATM and p53) and chromosome stabilization (TRF1 and TRF2) genes by real-time quantitative polymerization chain reaction. Data show that photobiomodulation reduces the mRNA levels from ATM and p53, as well reduces mRNA levels from TRF1 and TRF2 at 25 and 75 mW in injured skeletal muscle. In conclusion, photobiomodulation alters mRNA relative levels from genes related to genomic and telomere stabilization in injured skeletal muscle.

Genomic stability and telomere regulation in skeletal muscle tissue.

Muscle injuries are common, especially in sports and cumulative trauma disorder, and their repair is influenced by free radical formation, which causes damages in lipids, proteins and DNA. Oxidative DNA damages are repaired by base excision repair and nucleotide excision repair, ensuring telomeric and genomic stability. There are few studies on this topic in skeletal muscle cells. This review focuses on base excision repair and nucleotide excision repair, telomere regulation and how telomeric stabilization influences healthy muscle, injured muscle, exercise, and its relationship with aging. In skeletal muscle, genomic stabilization and telomere regulation seem to play an important role in tissue health, influencing muscle injury repair. Thus, therapies targeting mechanisms of DNA repair and telomeric regulation could be new approaches for improving repair and prevention of skeletal muscle injuries in young and old people.

Low laser therapy (photobiomodulation) on bacteria of pressure ulcers: in vitro studies / Laser de baixa potência (fotobiomodulação) sobre bacterias de úlceras de pressão: estudos in vitro

Os efeitos biológicos promovidos pelo laser de baixa potência resultam em cicatrização mais rápida das feridas. No entanto, as feridas são sistemas muito complexos, tanto do ponto de vista microbiano quanto do hospedeiro. Como a infecção é uma causa comum de cicatrização retardada, é importante entender o efeito da terapia com laser de baixa intensidade no crescimento bacteriano. Esta mini-revisão resume as evidências atuais sobre os efeitos do laser de baixa intensidade em estudos de bactérias in vitro. (AU)

The biological effects promoted by low power laser result in faster wound healing. However, wounds are very complex systems from both host and microbial point of view. Since infection is a common cause of delayed wound healing, it is important to understand the effect of low-level laser therapy in bacterial growth. This mini-review summaries the current evidence about effects of low level laser on bacteria vitro studies. (AU)

Heat delays skin wound healing in mice.

In vivo studies have shown that the combination of infrared radiation (IR) and visible light (VIS) is responsible for the activation of metaloproteinases, causing matrix degradation and damage to healthy skin. However, the role of heat originating from the VIS spectrum on wound healing remains poorly understood. Our objective was to investigate the macroscopic, microscopic and biochemical effects of heat induced by visible light on cutaneous wound healing in mice. Male mice were anesthetized, subjected to a cutaneous excisional wound and divided into two groups ( n = 10/group) exposed to 23℃ or 43℃ in a thermal chamber for 30 min every other day, for 13 days. On day 14, the animals were sacrificed, and their lesions were processed for histochemistry, immunohistochemistry and protein expression analysis. The wound area was 42% greater 11 days ( p < 0.01) and 29% greater 14 days ( p < 0.001) after wounding in the 43℃ group than in the 23℃ group. The 43℃ group presented a lower (17%) percentage of reepithelialized wounds ( p < 0.001) 14 days after wounding. The length of the epidermal gap was greater in the 43℃ group ( p < 0.01). The volume density of myofibroblasts and the number of F4/80-positive macrophages was greater in the 43℃ group ( p < 0.05). The 43℃ group showed increased protein expression of type III collagen ( p < 0.001), decreased protein expression of type I collagen ( p < 0.05), increased MMP-1 expression ( p < 0.05), and decreased MMP-2 activity ( p < 0.001). The protein expression of fibrillin-1 ( p < 0.001), MMP-12 ( p < 0.05), TGF-ß 1/2/3 ( p < 0.01) and ERK activation ( p < 0.05) was increased in the 43℃ group. Our results suggest that heat delays the stages of wound healing in mice.

Possible stressors in a neonatal intensive care unit at a university hospital. / Possíveis fatores estressantes na unidade de terapia intensiva neonatal em hospital universitário.

OBJECTIVE: To investigate possible stressors to which newborns are exposed in the neonatal intensive care unit. METHODS: The levels of continuous noise were checked by a decibel meter positioned near the ear of the newborn, brightness was observed by a light meter positioned in the incubator in front of the newborn's eyes, and temperature was checked through the incubator display. The evaluations were performed in three periods of the day, with ten measurements taken at one-minute intervals during each shift for the subsequent statistical analysis. RESULTS: All shifts showed noise above acceptable levels. Morning (p < 0.001), afternoon (p < 0.05) and night (p < 0.001) showed a significant increase compared to the control. The brightness significantly exceeded the normal range (p < 0.01) in the morning. We observed that only one of the incubators was within the normal temperature limits. CONCLUSION: The noise, brightness and temperature intensities were not in accordance with regulatory standards and thus might be possible stressors to newborns.

Possíveis fatores estressantes na unidade de terapia intensiva neonatal em hospital universitário / Possible stressors in a neonatal intensive care unit at a university hospital

RESUMO Objetivo: Verificar possíveis fatores estressantes aos quais os recém-nascidos estão expostos na unidade de terapia intensiva neonatal. Métodos: Os níveis de ruídos contínuos foram verificados por meio do decibelímetro posicionado próximo ao ouvido do recém-nascido; a luminosidade foi verificada pelo luxímetro posicionado dentro das incubadoras diante dos olhos do recém-nascido; e a verificação da temperatura se deu por meio da visualização do display das incubadoras. As avaliações foram realizadas em três períodos do dia, tendo sido realizadas dez medições com intervalo de 1 minuto em cada turno para posteriores análises estatísticas. Resultados: Todos os turnos apresentaram ruídos acima dos níveis aceitáveis. Manhã (p < 0,001), tarde (p < 0,05) e noite (p < 0,001) apresentaram aumento significativo comparado ao controle. A luminosidade excedeu os padrões de normalidade significativamente (p < 0,01) no período da manhã. Quanto à temperatura, observamos que apenas uma das incubadoras encontrava-se dentro dos padrões de normalidade. Conclusão: A intensidade dos ruídos, da luminosidade e da temperatura não estavam de acordo com as normas regulatórias, podendo ser assim um possível fator estressante para o recém-nascido.

ABSTRACT Objective: To investigate possible stressors to which newborns are exposed in the neonatal intensive care unit. Methods: The levels of continuous noise were checked by a decibel meter positioned near the ear of the newborn, brightness was observed by a light meter positioned in the incubator in front of the newborn's eyes, and temperature was checked through the incubator display. The evaluations were performed in three periods of the day, with ten measurements taken at one-minute intervals during each shift for the subsequent statistical analysis. Results: All shifts showed noise above acceptable levels. Morning (p < 0.001), afternoon (p < 0.05) and night (p < 0.001) showed a significant increase compared to the control. The brightness significantly exceeded the normal range (p < 0.01) in the morning. We observed that only one of the incubators was within the normal temperature limits. Conclusion: The noise, brightness and temperature intensities were not in accordance with regulatory standards and thus might be possible stressors to newborns.

Estudo retrospectivo de pacientes diagnosticados com câncer de mamainternados em hospital universitário / Retrospective study of patients diagnosed with breast cancer hospitalized in university hospital

O câncer de mama é a segunda neoplasia com maior incidência na população feminina, sendo o primeiro, o câncer de pele não melanoma. A concentração de quase 70% da população em grandes centros favorece a exposição aos fatores de risco ambientais, aos quais é atribuída relação direta ou indireta com 80% dos casos de câncer. Algumas substâncias químicas, o tabagismo, a poluição ambiental e a disparidade socioeconômica podem gerar influência na distribuição e na incidência do câncer nas diferentes regiões brasileiras. O estudo teve como objetivo realizar uma análise retrospectiva de pacientes, diagnosticadas com câncer de mama internadas em Hospital Universitário Sul Fluminense, Vassouras (RJ), entre o período de janeiro de 2010 a abril de 2014. A idade variou entre 20 a 90 anos, com idade média de 57,4 anos, em que houve predomínio da faixa etária de 50 a 59 anos. Em relação à cor da pele, notou-se maior incidência em mulheres brancas (51%). De acordo com a classificação histológica, o carcinoma predominante foi o do tipo ductal invasivo grau 2 de Nottingham. Com base nos nossos resultados, concluímos que o tipo de câncer com maior incidência ocorreu em grande parte em mulheres brancas e que o tratamento preconizado para a maioria dos casos foi a remoção cirúrgica, sendo associada à outra estratégia terapêutica, principalmente a quimioterapia.

Breast cancer is the second cancer with the highest incidence on the female population, and the firstis the non-melanoma skin cancer. The concentration of nearly 70% of the population in big citiesfavors exposure to environmental risk factors, which is attributed a direct or indirect relation to 80%of cancer cases. Some chemicals, smoking, environmental pollution and socioeconomic disparity cangenerate influence on the distribution and incidence of cancer in different Brazilian regions. Thestudy aimed at carring out a retrospective analysis of patients diagnosed with breast cancer admittedto a University Hospital Sul Fluminense, Vassouras (RJ), Brazil, in the period from January 2010 toApril 2014. The age ranged from 20 to 90 years, the mean age was 57.4 years, in which there was apredominance of the age group 50-59 years. With regard to skin color, it was seen a higher incidencein white women (51%). According to histological classification, the predominant cell carcinoma wasinvasive ductal type 2 grade of Nottingham. Based on our results, we conclude that the type of cancerwith the highest incidence occurred largely in white women and the treatment recommended formost cases was the surgical removal that was associated with another therapeutic strategy, especiallychemotherapy.

Elastase modifies bleomycin-induced pulmonary fibrosis in mice.

Pulmonary fibrosis (PF) is characterized by excessive accumulation of collagen in the lungs. Emphysema is characterized by loss of the extracellular matrix (ECM) and alveolar enlargement. We studied the co-participation of elastase-induced mild emphysema in bleomycin-induced PF in mice by analyzing oxidative stress, inflammation and lung histology. C57BL/6 mice were divided into four groups: control; bleomycin (0.1U/mouse); elastase (using porcine pancreatic elastase (PPE)+bleomycin (3U/mouse 14 days before 0.1U/mouse of bleomycin; PPE+B); elastase (3U/mouse). Mice were humanely sacrificed 7, 14 and 21 days after treatment with bleomycin or vehicle. PF was observed 14 days and 21 days after bleomycin treatment but was observed after 14 days only in the PPE+B group. In the PPE+B group at 21 days, we observed many alveoli and alveolar septa with few PF areas. We also observed marked and progressive increases of collagens 7, 14 and 21 days after bleomycin treatment whereas, in the PPE+B group, collagen deposition was observed only at 14 days. There was a reduction in activities of the antioxidant enzymes superoxide dismutase (p<0.05), catalase (p<0.01) and glutathione peroxidase (p<0.01) parallel with an increase in nitrite (p<0.01) 21 days after bleomycin treatment compared with the control group. These endpoints were also reduced (p<0.05, p<0.05 and p<0.01, respectively) and increased (p<0.01) in the PPE+B group at 21 days compared with the control group. Interleukin (IL)-1ß expression was upregulated (p<0.01) whereas IL-6 was downregulated (p<0.05) in the PPE+B group at 21 days compared with the control group. PF and emphysema did not coexist in our model of lung disease and despite increased levels of oxidative stress and inflammatory markers after combined stimulus (elastase and bleomycin) overall histology was improved to that of the nearest control group.

Effect of time-dependent cryotherapy on redox balance of quadriceps injuries.

Muscle trauma represents a high number of injuries in professional sport and recreation and may occur through several mechanisms. This study aims at analyzing time-dependent effects of cryotherapy on the redox balance in lesioned quadriceps muscles in F1 mice. Twenty male F1 mice were divided into five groups: (a) animals were not subjected to muscle lesioning or treatment (CTR); (b) quadriceps muscle was lesioned without treatment (L); (c) quadriceps muscle was lesioned and treated with cryotherapy for 5 min (LC5); (d) quadriceps muscle was lesioned and treated with cryotherapy for 20 min (LC20); and quadriceps muscle was lesioned and treated with cryotherapy for 40 min (LC40). The mice were euthanized; the quadriceps muscles were collected and subjected to analyses for levels of protein, hydroperoxides, nitrite, catalase (CAT) activity, oxidized glutathione (GSSG) and reduced glutathione (GSH). Protein levels were reduced in L (-39%; p < 0.05), LC5 (-54%; p < 0.05), LC20 (-40%; p < 0.05) and LC40 (-50%; p < 0.05) compared to CTR. There was an increase in lipid peroxidation in L (158%; p < 0.05), LC5 (300%; p < 0.01), LC20 (292%; p < 0.01) and LC40 (362%; p < 0.01) compared to CTR. We observed a significant increase in CAT activity in L (164%; p < 0.05) and LC5 (193%; p < 0.01) compared to CTR; a significant reduction in GSH in L (-60%; p < 0.05) and LC20 (-61%; p < 0.05) compared to CTR; and a significant increase in GSSG in LC5 (171%; p < 0.05) compared to CTR. In addition, GSH/GSSG was reduced in L (-89%; p < 0.01), LC5 (-95%; p < 0.01), LC20 (-59%; p < 0.05), and LC40 (-82%; p < 0.01) compared to CTR. This study showed that the cryotherapy does not improve the oxidative stress in lesioned muscles.

Low-level red laser improves healing of second-degree burn when applied during proliferative phase.

The aim of this study was to investigate the effects of low-level red laser on tissue repair in rats submitted to second-degree burn, evaluating if the timing of laser treatment influences the healing process. The animals had their backs shaved and divided as follows: control group (n = 12)-rats burned and not irradiated, early laser group (n = 12)-rats burned and irradiated from day 1 after injury for five consecutive days, and late laser group (n = 14)-rats burned and irradiated from day 4 after injury for five consecutive days. Laser irradiation was according to a clinical protocol (20 J/cm(2), 100 mW, continuous wave emission mode, 660 nm) as recommended by the laser device manufacturer. Half of the animals were sacrificed 10 days after burn, and the other animals were sacrificed 21 days after burn. The late laser group accelerated wound contraction 10 and 21 days after burn. The late laser group accelerated reepithelialization 18 days after burn. The late laser group increases the granulation tissue 10 and 21 days after burn. Both irradiated groups increased type III collagen expression and TGF-ß 21 days after burn. Both irradiated groups increased macrophage and myofibroblast numbers 10 days after burn and decreased 21 days after. Low-level red laser exposure contributes to the process of tissue repair of second-degree burns, but the intervention during proliferative phase is crucial in the final outcome of the repair process.

Expression of DNA repair genes in burned skin exposed to low-level red laser.

Although red laser lights lie in the region of non-ionizing radiations in the electromagnetic spectrum, there are doubts whether absorption of these radiations causes lesions in the DNA molecule. Our aim was to investigate the expression of the genes involved with base excision and nucleotide excision repair pathways in skin tissue submitted to burn injury and exposed to low-level red laser. Wistar rats were divided as follows: control group-rats burned and not irradiated, laser group-rats burned and irradiated 1 day after injury for five consecutive days, and later laser group-rats injured and treated 4 days after injury for five consecutive days. Irradiation was performed according to a clinical protocol (20 J/cm(2), 100 mW, continuous wave emission mode). The animals were sacrificed on day 10, and scarred tissue samples were withdrawn for total RNA extraction, complementary DNA (cDNA) synthesis, and evaluation of gene expression by quantitative polymerase chain reaction. Low-level red laser exposure (1) reduces the expression of APE1 messenger (mRNA), (2) increases the expression of OGG1 mRNA, (3) reduces the expression of XPC mRNA, and (4) increases the expression of XPA mRNA both in laser and later laser groups. Red laser exposure at therapeutic fluences alters the expression of genes related to base excision and nucleotide excision pathways of DNA repair during wound healing of burned skin.

The oxidative response of mouse hearts is modulated by genetic background.

BACKGROUND: Smoking plays an important role in cardiovascular diseases. However, the reasons why some individuals develop those diseases and others do not remain to be explained. OBJECTIVE: This study aimed at assessing the redox profile of the heart of different mouse strains after exposure to cigarette smoke. METHODS: Male mice of the Swiss (n = 10), C3H (n = 10), BALB/c (n = 10) and C57BL/6 (n = 10) strains were exposed to cigarette smoke (12 cigarettes/day), while their respective controls (n = 10) were exposed to ambient air for 60 days. After being euthanized, their heart was removed for biochemical analyses. RESULTS: Although the malondialdehyde content did not increase in any of the groups, catalase activity decreased in the Swiss (p < 0.05) and BALB/c (p < 0.05) strain mice as compared with their respective control groups, while myeloperoxidase decreased in the C3H (p < 0.05) and C57BL/6 (p < 0.001) strain mice as compared with their respective control groups. The reduced glutathione content decreased in the Swiss, C3H, C57BL/6 (p < 0.05) and BALB/c (p < 0,001) strain mice as compared with their respective control groups. Regarding reduced glutathione content, an increase was observed in the Swiss strain mice (p < 0.05), while a decrease was observed in the C3H (p < 0.05) and BALB/c (p < 0.001) strain mice as compared with their respective control groups. The reduced glutathione/reduced glutathione ratio showed a reduction in the Swiss and C57BL/6 (p < 0.05) strain mice as compared with their respective control groups. CONCLUSIONS: The genetic background of mice can influence the antioxidant response after exposure to cigarette smoke and seems to be a determinant factor for redox imbalance in Swiss and C57BL/6 strain mice. Understanding antioxidant responses and genetic background of C3H and BALB/c strain mice might provide important information regarding cardiac resistance to cigarette smoke.

A resposta oxidativa em corações de camundongos é modulada por background genético / The oxidative response of mouse hearts is modulated by genetic background

FUNDAMENTO: o tabagismo apresenta importante papel sobre as doenças cardiovasculares, entretanto permanecem pouco compreendidos os motivos pelos quais alguns seres humanos as desenvolvem e outros não. OBJETIVO: nosso objetivo foi analisar o perfil redox do coração de diferentes linhagens de camundongos após exposição à fumaça de cigarro. MÉTODOS: camundongos machos suíços (n = 10), C3H (n = 10), BALB/c (n = 10) e C57BL/6 (n = 10) foram expostos à fumaça de cigarro (12 cigarros/dia), enquanto os respectivos controles (n = 10) ao ar ambiente por 60 dias. Após sacrifício, o coração foi retirado para análises bioquímicas. RESULTADOS: embora o conteúdo de malondialdeído não tenha aumentado em nenhum grupo, a atividade da catalase diminuiu no grupo suíço (p < 0,05), BALB/c (p < 0,05) quando comparados aos respectivos grupos-controle, enquanto a mieloperoxidase diminuiu no grupo C3H (p < 0,05) e C57BL/6 (p < 0,001) quando comparados aos respectivos grupos controle. O conteúdo de glutationa reduzida diminuiu nos grupos suíço, C3H, C57BL/6 (p < 0,05) e no grupo BALB/c (p < 0,001) quando comparados com os respectivos controles. Observamos aumento do conteúdo da glutationa oxidada no grupo Suíço (p < 0,05) e diminuição nos grupos C3H (p < 0,05) e BALB/c (p < 0,001) quando comparados aos respectivos grupos-controle. A razão glutationa reduzida/ glutationa oxidada apresentou redução nos grupos suíço e C57BL/6 (p < 0.05) quando comparados aos grupos controle. CONCLUSÃO: o background genético nos camundongos pode influenciar na resposta antioxidante após a exposição à fumaça de cigarro e parece ser um fator determinante para o desequilíbrio redox no suíço e C57BL/6. Compreender as respostas antioxidantes e do background genético C3H e BALB/c podem fornecer importantes informações quanto à resistência cardíaca a fumaça de cigarro.

BACKGROUND: Smoking plays an important role in cardiovascular diseases. However, the reasons why some individuals develop those diseases and others do not remain to be explained. OBJECTIVE: This study aimed at assessing the redox profile of the heart of different mouse strains after exposure to cigarette smoke. METHODS: Male mice of the Swiss (n = 10), C3H (n = 10), BALB/c (n = 10) and C57BL/6 (n = 10) strains were exposed to cigarette smoke (12 cigarettes/day), while their respective controls (n = 10) were exposed to ambient air for 60 days. After being euthanized, their heart was removed for biochemical analyses. RESULTS: Although the malondialdehyde content did not increase in any of the groups, catalase activity decreased in the Swiss (p < 0.05) and BALB/c (p < 0.05) strain mice as compared with their respective control groups, while myeloperoxidase decreased in the C3H (p < 0.05) and C57BL/6 (p < 0.001) strain mice as compared with their respective control groups. The reduced glutathione content decreased in the Swiss, C3H, C57BL/6 (p < 0.05) and BALB/c (p < 0,001) strain mice as compared with their respective control groups. Regarding reduced glutathione content, an increase was observed in the Swiss strain mice (p < 0.05), while a decrease was observed in the C3H (p < 0.05) and BALB/c (p < 0.001) strain mice as compared with their respective control groups. The reduced glutathione/reduced glutathione ratio showed a reduction in the Swiss and C57BL/6 (p < 0.05) strain mice as compared with their respective control groups. CONCLUSIONS: The genetic background of mice can influence the antioxidant response after exposure to cigarette smoke and seems to be a determinant factor for redox imbalance in Swiss and C57BL/6 strain mice. Understanding antioxidant responses and genetic background of C3H and BALB/c strain mice might provide important information regarding cardiac resistance to cigarette smoke.