RESUMO
The rapid development of nanomedicine has created a high demand for silver, copper and copper oxide nanoparticles. Due to their high reactivity and potent antimicrobial activity, silver and copper-based nanomaterials have been playing an important role in the search for new alternatives for the treatment of several issues of concern, such as pathologies caused by bacteria and viruses. Viral diseases are a significant and constant threat to public health. The most recent example is the pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this context, the object of the present review is to highlight recent progress in the biomedical uses of these metal nanoparticles for the treatment and prevention of human viral infections. We discuss the antiviral activity of AgNPs and Cu-based NPs, including their actions against SARS-CoV-2. We also discuss the toxicity, biodistribution and excretion of AgNPs and CuNPs, along with their uses in medical devices or on inert surfaces to avoid viral dissemination by fomites. The challenges and limitations of the biomedical use of these nanoparticles are presented.
Assuntos
Tratamento Farmacológico da COVID-19 , Nanopartículas Metálicas , Cobre , Humanos , Nanopartículas Metálicas/uso terapêutico , Óxidos , SARS-CoV-2 , Prata/farmacologia , Distribuição TecidualRESUMO
BACKGROUND: The social and economic impact of dementia for the development of accessible and sustainable care for individuals with dementia (IwD). Physical exercise has been seen as a beneficial non-pharmacological therapy in the prevention and management of dementia, and possible benefits may not only impact on participants, but also indirectly on their caregivers. Thus, this quasi-experimental non-randomized study aimed to analyze the effects of an exercise intervention on functional capacity, behavioural and psychological symptoms in dementia (BPSD) and quality of life of institutionalized older adults with dementia, perceived by their formal caregivers. METHODS: Sixty-four institutionalized older adults (from both genders, aged 65-93 yrs. old), clinically diagnosed with dementia, were divided into two groups: control group (CG, continued with usual care, n = 26) and exercise group (EG, 6-month supervised multicomponent exercise intervention, n = 38). Nine caregivers (female, aged 28-47 yrs. old) from nine different nursing homes, reported about their distress related to BPSD and proxy-reported about participants' functional capacity (Katz index), quality of life (QoL-AD), BPSD (NPI) before and after 6 months of an exercise intervention (aerobic, muscular resistance, flexibility and postural exercises). RESULTS: A two-way ANOVA, with repeated measures, revealed significant group and time interactions on Total Katz index and QoL-AD. The CG's performance functional capacity and quality of life score worsen over time while in EG maintains these values after the exercise intervention. Moreover, formal caregiver's distress triggered by apathy and disinhibition increased in CG while after 6 months of an exercise intervention no alterations were seen regarding these distress causes in EG. No significant main effects were observed for total NPI score or NPI distress. CONCLUSIONS: Overall results show that after the exercise intervention, IwD from the EG, was capable of preserving the functional capacity, quality of life and neuropsychiatric symptoms were attenuate, contributing to a lower load of distress for the caregivers. TRIAL REGISTRATION: clinicaltrials.gov , NCT04095962 . Retrospectively registered on 19 September 2019.
Assuntos
Cuidadores , Demência , Idoso , Idoso de 80 Anos ou mais , Demência/terapia , Exercício Físico , Terapia por Exercício , Feminino , Humanos , Masculino , Qualidade de VidaRESUMO
This cross-sectional study investigated the association of physical fitness with cognitive function, functional capacity and quality of life among institutionalized older adults with dementia. One hundred and two older adults aged 78.0 ± 8.4 years, predominantly female (67.6%), with neurocognitive disorder due to Alzheimer's disease (AD) (49.2%), vascular dementia (14.7%), Parkinson's disease (2%), dementia with Lewy bodies (2%) or unspecified dementia (32.1%) participated in the present study. Regression analyses were used to examine associations between physical fitness components (Senior Fitness Test) and cognitive function (Mini-Mental State Examination), functional capacity (Katz Index of Independence in Activities of Daily Living) and Quality of Life (QoL)-Alzheimer's Disease scale. Univariate regression indicates that strength, flexibility, agility/dynamic balance and aerobic endurance are relevant for cognitive function, physical capacity and perceived QoL in institutionalized older people with dementia. After multiple regression analyses, adjusted for body mass index (BMI), results showed that aerobic endurance had a significant positive association with Total Katz Index. For both, caregiver perception of QoL-AD and global QoL-AD, BMI remained significantly and positively associated. Agility-dynamic balance presented a significant negative relation with global QoL-AD. Overall, our findings suggest that better physical fitness is important for cognition and autonomous functional capacity and that it has positive repercussions on the QoL in institutionalized older adults with dementia. Consequently, exercise-based therapeutic strategies aiming to improve physical fitness should be implemented.
Assuntos
Atividades Cotidianas , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Cognição , Estudos Transversais , Feminino , Humanos , Aptidão FísicaRESUMO
Metal nanoparticles and metal oxides nanoparticles (MNPs/MONPs) have been widely included in a great diversity of products and industrial applications and they are already a part of our everyday life. According to estimation studies, their production is expected to increase exponentially in the next few years. Consequently, soil has been suggested as the main sink of MNPs/MONPs once they are deliberately or accidentally released into the environment. The potential negative perturbations that may result on soil microbial communities and ecological processes are resulting in concerns. Several nano-toxicological studies of MNPs/MONPs, reported so far, have focused on aquatic organisms, animals, and soil invertebrates. However, during recent years, the studies have been oriented to understand the effects of MNPs/MONPs on microbial communities and their interaction with soil components. The studies have suggested that MNPs/MONPs are one of the most toxic type to soil biota, amongst different types of nanomaterials. This may threaten soil health and fertility, since microbial communities are known to support important biological processes and ecosystem services such as the nutrient cycling, whereby their protection against the environmental pollution is imperative. Therefore, in this review we summarize the actual knowledge available from the last five years (2013-2018) and gaps about the potential negative, positive or neutral effects produced on soil by different classes of MNPs/MONPs. A particular emphasis has been placed on the associated soil microorganisms and biological processes. Finally, perspectives about future research are discussed.
Assuntos
Nanopartículas Metálicas , Metais , Óxidos , Microbiologia do Solo , Poluentes do Solo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Metais/química , Metais/toxicidade , Microbiota , Nanotecnologia , Óxidos/química , Óxidos/toxicidade , Solo/química , Poluentes do Solo/química , Poluentes do Solo/toxicidadeRESUMO
This study investigated the agreement and reliability of oxygen uptake (VÌO2), VÌO2 reserve (VÌO2 R), heart rate (HR) and power output at intensities corresponding to the gas exchange threshold (GET) and heart rate variability threshold (HRVT) during maximal cardiopulmonary exercise testing (CPET) in obese and eutrophic adolescents. A further aim was to establish whether the HRVT was able to detect changes in cardio-respiratory fitness in obese adolescents after 3 months of recreational soccer practice. First, 25 obese and 10 eutrophic adolescents (ages 12-17) visited the laboratory twice to perform cycling CPET to test the reliability of CPET outcomes at GET and HRVT. Furthermore, the level of agreement between GET and HRVT was determined for a subgroup of 10 obese adolescents after performing a 3-month recreational soccer program. No significant difference was found for VÌO2, %VÌO2 R, HR and power output at the GET and HRVT (P>0.05), which were equally able to detect improvements in aerobic fitness after the soccer intervention. Correlations between GET and HRVT for VÌO2 and %VÌO2 R ranged from 0.89 to 0.95 (P<0.001) and test-retest reliability ranged from 0.59 to 0.82 (P<0.006). Overall, HRVT seems to be a reliable alternative for prescribing aerobic exercise intensity in obese adolescents.
Assuntos
Limiar Anaeróbio/fisiologia , Frequência Cardíaca/fisiologia , Obesidade Infantil/fisiopatologia , Aptidão Física/fisiologia , Adolescente , Estudos de Casos e Controles , Criança , Teste de Esforço , Feminino , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Reprodutibilidade dos Testes , Futebol/fisiologiaRESUMO
The effects of a 5-month intervention of football instruction and practice on the perceived psychological status and body composition of overweight boys were examined. Twelve boys (8-12 years; body mass index ≥ 85th percentile) participated in a structured 5-month football program, consisting of four weekly 60-90 min sessions with mean heart rate > 80%HRmax [football group (FG)]. A control group (CG) included eight boys of equivalent age from an obesity clinic located in the same area as the school. Both groups participated in two sessions of 45-90-min physical education per week at school. Indicators of perceived psychological status included body image, self-esteem, attraction to participation in physical activity, and perceived physical competence measured with standardized questionnaires. Body composition was evaluated using dual-energy X-ray absorptiometry. From baseline through 5 months, FG improved (P < 0.05) in all indicators of psychological status (%Δ = +11.7 to +29.2%) compared with CG (%Δ = -32.1 to +0.5%). Changes in percentage body fat and lean body mass, however, did not differ between FG and CG. The findings suggest that a 5-month football intervention program was effective in improving the psychological status of overweight boys but did not significantly alter body composition.
Assuntos
Composição Corporal , Imagem Corporal , Sobrepeso/psicologia , Autoimagem , Futebol/fisiologia , Futebol/psicologia , Absorciometria de Fóton , Adiposidade , Criança , Humanos , Masculino , Sobrepeso/fisiopatologia , Testes Psicológicos , AutoeficáciaRESUMO
AIM: The present study aims (1) to provide reference percentile charts for the following measures of Physical Fitness (PF): the sit-and-reach, handgrip, standing long jump, 50 yards' dash, 4x10m shuttle run and 1-mile run/walk tests in children aged 6 to 10 years, and (2) to compare the performance of the Portuguese children with their age- and sex peers. METHODS: A total of 3804 Portuguese children (1985 boys and 1819 girls) aged 6-10 years old participated in this study. The sample was stratified from 20 public elementary schools and children were randomly selected in each school. Charts were separately built for each sex using the LMS method. RESULTS: Boys showed better results than girls in handgrip, standing long jump, 50 yards' dash, 4x10 m shuttle run and 1-mile run/walk, while girls are better performers than boys in sit-and-reach. CONCLUSION: Age- and gender- percentiles for a set of physical fitness tests for 6-10 year old (primary school) Portuguese children have been established. Boys showed greater overall PF than girls, except in the flexibility test, in which girls performed better. The reported normative values provide ample opportunities to accurately detect individual changes during childhood. These reference values are especially important in healthcare and educational settings, and can be added to the worldwide literature on physical fitness values in children.
Assuntos
Exercício Físico , Aptidão Física , Fatores Etários , Criança , Feminino , Humanos , Masculino , Portugal , Fatores SexuaisRESUMO
The soil is a vital resource that hosts many microorganisms crucial in biogeochemical cycles and ecosystem health. However, human activities such as the use of metal nanoparticles (MNPs), pesticides and the impacts of global climate change (GCCh) can significantly affect soil microbial communities (SMC). For many years, pesticides and, more recently, nanoparticles have contributed to sustainable agriculture to ensure continuous food production to sustain the significant growth of the world population and, therefore, the demand for food. Pesticides have a recognized pest control capacity. On the other hand, nanoparticles have demonstrated a high ability to improve water and nutrient retention, promote plant growth, and control pests. However, it has been reported that their accumulation in agricultural soils can also adversely affect the environment and soil microbial health. In addition, climate change, with its variations in temperature and extreme water conditions, can lead to drought and increased soil salinity, modifying both soil conditions and the composition and function of microbial communities. Abiotic stressors can interact and synergistically or additively affect soil microorganisms, significantly impacting soil functioning and the capacity to provide ecosystem services. Therefore, this work reviewed the current scientific literature to understand how multiple stressors interact and affect the SMC. In addition, the importance of molecular tools such as metagenomics, metatranscriptomics, proteomics, or metabolomics in the study of the responses of SMC to exposure to multiple abiotic stressors was examined. Future research directions were also proposed, focusing on exploring the complex interactions between stressors and their long-term effects and developing strategies for sustainable soil management. These efforts will contribute to the preservation of soil health and the promotion of sustainable agricultural practices.
Assuntos
Mudança Climática , Nanopartículas Metálicas , Praguicidas , Microbiologia do Solo , Nanopartículas Metálicas/toxicidade , Poluentes do Solo , Solo/química , Ecossistema , Microbiota/efeitos dos fármacos , Agricultura/métodosRESUMO
Anthropometric characteristics, physical fitness and technical skills of under-19 (U19) soccer players were compared by competitive level (elite, n=95; non-elite, n=85) and playing position (goalkeeper, central defender, fullback, midfield, forward). Fitness tests included 5- and 30-m sprints, agility, squat jump (SJ) and countermovement jump (CMJ), strength and Yo-Yo intermittent endurance test level 2 (Yo-Yo IE2). Soccer-specific skills included ball control and dribbling. Independent of position, elite players presented more hours of training per year than non-elite players (d>1.2). Stature and body mass discriminated elite from non-elite players among goalkeepers and central defenders (d>0.6). Major differences were noted between elite and non-elite goalkeepers for SJ, CMJ, Yo-Yo IE2, and ball control (d>1.2). Elite central defenders performed better than their non-elite counterparts in SJ and ball control tests (d>1.2). Elite players presented better agility and Yo-Yo IE2 performances than non-elite players within all positional roles (d>0.6). In conclusion, U19 players differed in anthropometric characteristics, physical fitness and technical skills by competitive level within field positions.
Assuntos
Desempenho Atlético/fisiologia , Teste de Esforço , Aptidão Física/fisiologia , Futebol/fisiologia , Adolescente , Análise de Variância , Estatura/fisiologia , Índice de Massa Corporal , Humanos , Joelho/fisiologia , Masculino , Músculo Esquelético/fisiologia , TorqueRESUMO
An accurate evaluation of training load is paramount for the planning and periodization of training. The aim of the present study was to evaluate the relationship between a new method to monitor training load in soccer (Visual Analogic Scale training load; VAS-TL), and two established heart rate-based methods (TRIMP and Edwards' method). 51 soccer players (age 15.6±0.3 years) answered 2 questions to assess perceived exertion and fatigue (VAS1-TL, and VAS2-TL) after training sessions and official matches. Performance in the Yo-Yo tests, VAS scores and heart rate of training sessions and matches, and match activity were analysed. We found significant correlations (r=0.60-0.72; p<0.05) between VAS-TL, TRIMP, and the Edwards' training load method, with the highest correlations achieved in the matches. Although the different methods to monitor training load were correlated with the distance covered during the match (r=0.53-0.78; p<0.05), only VAS1-TL was associated with high-intensity activities (r=0.43-0.54; p<0.05). The new VAS-based perceived exertion method to monitor training load is easy to apply and is sensitive to differences in positional role and physical capacity. Thus, the applied method may be used in addition to the usual training load methods, allowing for daily quantification of individual training load in soccer.
Assuntos
Monitorização Fisiológica/métodos , Educação Física e Treinamento , Esforço Físico/fisiologia , Futebol/fisiologia , Inquéritos e Questionários , Adolescente , Frequência Cardíaca , Humanos , Fadiga Muscular , Percepção , Resistência Física , Reprodutibilidade dos Testes , Estudos de Tempo e MovimentoRESUMO
This study examined the association between demographic [age, sex, socioeconomic status (SES)] and socio-cultural [father, mother, sibling physical activity (PA); peers and physical education teacher influences] correlates and low, moderate and high levels of PA among Portuguese adolescents aged 10-18 years. A total of 3352 males and females attending basic and secondary schools, their parents and siblings were sampled across four regions of Portugal. PA was assessed with a psychometrically validated questionnaire. Multinomial logistic regression was used. Age was positively related with moderate and high PA. Boys and adolescents of high SES were more likely to participate in moderate and high PA. Adolescents were more likely to participate in high PA when theirs mother and sibling(s) also participated. Peers had a positive influence on participation in moderate and high PA, while physical education teachers did not have an influence. The results indicated that demographic and socio-cultural correlates--in particular age, sex, SES, mother and sibling PA, and peer influence--were significantly associated with adolescent PA. These results also suggested that interventions should focus on girls and low SES adolescents who face higher risk of inactivity.
Assuntos
Comportamento do Adolescente/fisiologia , Exercício Físico , Adolescente , Fatores Etários , Criança , Estudos Transversais , Docentes , Feminino , Humanos , Modelos Logísticos , Masculino , Pais , Grupo Associado , Portugal , Fatores Sexuais , Irmãos , Fatores Socioeconômicos , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: To model changes in body mass index (BMI), including its stability, and to investigate the association between physical activity, 1-mile run/walk and levels of gross motor coordination and BMI during 5 consecutive years. DESIGN: A longitudinal study of children 6 years of age at baseline followed at annual intervals over 5 years. SUBJECTS: A total of 285 children (143 boys and 142 girls) were enrolled in grade 1 (age 6 years) and followed through grade 5 (age 10 years). MEASUREMENTS: BMI was recorded and physical activity was assessed by questionnaire, aerobic fitness was evaluated with the 1-mile run/walk and gross motor coordination was measured with the KTK test battery (Körperkoordination test für Kinder). Multilevel modelling techniques were for the primary analysis. RESULTS: Changes in BMI showed similar curvilinear trends in boys and girls, with ample inter-individual crossing trajectories that is, low tracking. Longitudinal changes in physical activity (PA) and aerobic fitness were not significantly associated with BMI-changes during the 5 years. Children who were more proficient in their motor coordination showed lower values of BMI during the 5 years. CONCLUSIONS: BMI trajectories of both boys and girls show low tracking of BMI-values. Considerable inter-individual variation exists both in baseline BMI-values and changes (velocity and acceleration) over time. PA and fitness were not associated with BMI-changes, but gross motor function was negatively associated with BMI-changes. No gender-specific associations were found. If confirmed in other populations these observations could be translated in the promotion of physical activities that improve gross motor function in children aged 6-10 years. This seems to be of major importance for the physical education curriculum of primary school children.
Assuntos
Atividade Motora/fisiologia , Destreza Motora/fisiologia , Aptidão Física/fisiologia , Açores/epidemiologia , Índice de Massa Corporal , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Reprodutibilidade dos Testes , Inquéritos e Questionários , Análise e Desempenho de TarefasRESUMO
Adolescence is often viewed as a critical period for selection in youth soccer. The present study compared the characteristics of regionally selected and non-selected under-14 players (U-14) as a group and by position. Players were classified as local (n=69) and regional (n=45). Weight, height, skinfolds, functional capacities, soccer skills and goal orientation were measured and skeletal age was assessed with the Fels method. Factorial ANOVA was used to test the effect of selection, position and respective interaction terms, while discriminant analysis was used to identify the variables that contributed to selection. Selected players had an advanced maturity status (F=24.97, p<0.01), were heavier (F=30.67, p<0.01) and taller (F=35.07, p<0.01); performed better in explosive power (F=21.25, p<0.01), repeated sprints (F=20.04, p<0.01) and ball control (F=3.69, p<0.05); and were more ego oriented (F=13.29, p<0.01). The 2 competitive groups did not differ in agility, aerobic endurance, dribbling, shooting, passing, and task orientation. Position-related variation was negligible. The percentage of players who were correctly classified in the original groups was slightly lower when the analysis was performed for the total sample (86%) than by position (86-90%). Future research on talent identification and selection should adopt a multidimensional approach including variables related to the physiological, perceptual, cognitive and tactical demands.
Assuntos
Desenvolvimento do Adolescente/fisiologia , Desempenho Atlético/fisiologia , Futebol/fisiologia , Adolescente , Determinação da Idade pelo Esqueleto , Análise de Variância , Antropometria , Análise Discriminante , Humanos , Masculino , Resistência Física/fisiologiaRESUMO
Silver nanoparticles (AgNPs) have attracted remarkable attention due to their powerful antimicrobial action as well as their particular physicochemical properties. This has led to their application in a wide variety of products with promising results. However, their interaction with the environment and toxicity in live terrestrial or aquatic organisms is still a matter of intense debate. More detailed knowledge is still required about the toxicity of AgNPs, their possible uptake mechanisms and their adverse effects in live organisms. Several studies have reported the interactions and potential negative effects of AgNPs in different organisms. In this review, we report and discuss the current state of the art and perspectives for the impact of AgNPs on different organisms present in the environment. Recent progress in interpreting uptake, translocation and accumulation mechanisms in different organisms and/or living animals are discussed, as well as the toxicity of AgNPs and possible tolerance mechanisms in live organisms to cope with their deleterious effects. Finally, we discuss the challenges of accurate physicochemical characterization of AgNPs and their ecotoxicity in environmentally realistic conditions such as soil and water media.
Assuntos
Poluentes Ambientais/toxicidade , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Animais , Organismos Aquáticos/efeitos dos fármacos , Humanos , Plantas/efeitos dos fármacos , Microbiologia do SoloRESUMO
In this work we explore the noise characteristics in lithographically-defined two terminal devices containing self-assembled InAs/InP quantum dots. The experimental ensemble of InAs dots show random telegraph noise (RTN) with tuneable relative amplitude-up to 150%-in well defined temperature and source-drain applied voltage ranges. Our numerical simulation indicates that the RTN signature correlates with a very low number of quantum dots acting as effective charge storage centres in the structure for a given applied voltage. The modulation in relative amplitude variation can thus be associated to the altered electrostatic potential profile around such centres and enhanced carrier scattering provided by a charged dot.
Assuntos
Interpretação Estatística de Dados , Iluminação/instrumentação , Modelos Estatísticos , Pontos Quânticos , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
The integration of optical detection methods in continuous flow microsystems can highly extend their range of application, as long as some negative effects derived from their scaling down can be minimized. Downsizing affects to a greater extent the sensitivity of systems based on absorbance measurements than the sensitivity of those based on emission ones. However, a careful design of the instrumental setup is needed to maintain the analytical features in both cases. In this work, we present the construction and evaluation of a simple miniaturized optical system, which integrates a novel flow cell configuration to carry out chemiluminescence (CL) measurements using a simple photodiode. It consists of a micromixer based on a vortex structure, which has been constructed by means of the low-temperature cofired ceramics (LTCC) technology. This mixer not only efficiently promotes the CL reaction due to the generated high turbulence but also allows the detection to be carried out in the same area, avoiding intensity signal losses. As a demonstration, a flow injection system has been designed and optimized for the detection of cobalt(II) in water samples. It shows a linear response between 2 and 20 microM with a correlation of r > 0.993, a limit of detection of 1.1 microM, a repeatability of RSD = 12.4%, and an analysis time of 17 s. These results demonstrate the suitability of the proposal to the determination of compounds involved in CL reactions by means of an easily constructed versatile device based on low-cost instrumentation.
RESUMO
The use of nanoparticle-based transdermal delivery systems is a promising approach to efficiently carry and deliver therapeutic agents for dermal and systemic administration. Nitric oxide (NO) is a key molecule that plays important roles in human skin such as the control of skin homeostasis, skin defense, control of dermal blood flow, and wound healing. In addition, human skin contains stores of NO derivatives that can be mobilized and release free NO upon UV irradiation with beneficial cardiovascular effects, for instance the control of blood pressure. In this work, the NO donor precursor glutathione (GSH) was encapsulated (encapsulation efficiency of 99.60%) into ultra-small chitosan nanoparticles (CS NPs) (hydrodynamic size of 30.65 ± 11.90 nm). GSH-CS NPs have a core-shell structure, as revealed by atomic force microscopy and X-ray photoelectron spectroscopy, in which GSH is protected in the nanoparticle core. Nitrosation of GSH by nitrous acid led to the formation of the NO donor S-nitrosogluthathione (GSNO) into CS NPs. The GSNO release from the CS NPs followed a Fickian diffusion described by the Higuchi mathematical model. Topical application of GSNO-CS NPs in intact human skin significantly increased the levels of NO and its derivatives in the epidermis, as assayed by confocal microscopy, and this effect was further enhanced by skin irradiation with UV light. Therefore, NO-releasing CS NPs are suitable materials for transdermal NO delivery to local and/or systemic therapies.
RESUMO
Muscular atrophy is a progressive degeneration characterized by muscular proteolysis, loss of mass and decrease in fiber area. Tendon rupture induces muscular atrophy due to an intrinsic functional connection. Local inhibition of nitric oxide synthase (NOS) by Nω-nitro-L-arginine methyl ester (L-NAME) accelerates tendon histological recovery and induces functional improvement. Here we evaluate the effects of such local nitrergic inhibition on the pattern of soleus muscle regeneration after tenotomy. Adult male Wistar rats (240 to 280 g) were divided into four experimental groups: control (n=4), tenotomized (n=6), vehicle (n=6), and L-NAME (n=6). Muscular atrophy was induced by calcaneal tendon rupture in rats. Changes in muscle wet weight and total protein levels were determined by the Bradford method, and muscle fiber area and central core lesion (CCL) occurrence were evaluated by histochemical assays. Compared to tenotomized (69.3±22%) and vehicle groups (68.1%±17%), L-NAME treatment induced an increase in total protein level (108.3±21%) after 21 days post-injury. A reduction in fiber areas was observed in tenotomized (56.3±1.3%) and vehicle groups (53.9±3.9%). However, L-NAME treatment caused an increase in this parameter (69.3±1.6%). Such events were preceded by a remarkable reduction in the number of fibers with CCL in L-NAME-treated animals (12±2%), but not in tenotomized (21±2.5%) and vehicle groups (19.6±2.8%). Altogether, our data reveal that inhibition of tendon NOS contributed to the attenuation of atrophy and acceleration of muscle regeneration.
Assuntos
Inibidores Enzimáticos/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Recuperação de Função Fisiológica/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Animais , Masculino , Atrofia Muscular , Óxido Nítrico Sintase/metabolismo , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/fisiologia , Regeneração/fisiologia , TenotomiaRESUMO
BACKGROUND: Despite progression in treatment of gastric cancer, prognosis of patients remains poor, in part due to the low rate of diagnosis during its early stages. This paradigm implies the necessity to identify molecular biomarkers for early gastric cancer diagnosis, as well as for disease monitoring, thus contributing to the development of new therapeutic approaches. In a previous study, performed by array-Comparative Genomic Hybridization, we described for the first time in literature recurrent amplification of RTEL1 and ABCA13 genes in gastric cancer. Thus, the aim of the present study was to validate recurrent amplification of RTEL1 and ABCA13 genes and associate CNV status with clinicopathological data. FINDINGS: Results showed RTEL1 and ABCA13 amplification in 38 % of samples. Statistical analysis demonstrated that RTEL amplification is more common in older patients and more associated with intestinal type and ABCA13 amplification increases the risk of lymph node metastasis and is more common in men. Co-amplification of these genes showed a significant association with advanced staging. CONCLUSIONS: aCGH is a very useful tool for investigating novel genes associated with carcinogenesis and RTEL1 amplification may be important for the development of gastric cancer in older patients, besides being a probable event contributing for chromosomal instability in intestinal gastric carcinogenesis. ABCA13 amplification may have age-specific function and could be considered a useful marker for predicting lymph node metastasis in resected gastric cancer patients in early stage. Lastly, RTEL1 and ABCA13 synergistic effect may be considered as a putative marker for advanced staging in gastric cancer patients.