Smoking Intensity Increases Diaphragm Muscle Injury: A Clinicopathologic Study.

BACKGROUND: Studying the effects of smoking intensity is important to evaluate the risk of tobacco use on a range of illnesses, such as as sarcopenia among the elderly. Thus, this study aimed to analyze the effects of pack-years of cigarette smoking on the diaphragm muscle (DIAm) histopathology of postmortem samples. METHODS: Subjects were divided into three groups: never-smoker (n = 46); less than 30 pack-years of smoking (n = 12); and more than 30 pack-years of smoking (n = 30). Diaphragm samples were stained with Picrosirius red and hematoxylin and eosin stain for general structure. RESULTS: Participants with more than 30 pack-years of cigarette smoking had a significant increase in adipocytes, blood vessels and collagen deposit, as well as an increase in histopathological alterations. CONCLUSIONS: Pack-years of smoking was associated with DIAm injury. However, further clinicopathological studies are needed to confirm our findings.

Smoking intensity increases diaphragm muscle injury: a clinicopathologic study

BACKGROUND: Studying the effects of smoking intensity is important to evaluate the risk of tobacco use on a range of illnesses, such as sarcopenia among the elderly. Thus, this study aimed to analyze the effects of pack-years of cigarette smoking on the diaphragm muscle (DIAm) histopathology of postmortem samples. METHODS: Subjects were divided into three groups: never-smoker (n = 46); less than 30 pack-years of smoking (n = 12); and more than 30 pack-years of smoking (n = 30). Diaphragm samples were stained with Picrosirius red and hematoxylin and eosin stain for general structure. RESULTS: Participants with more than 30 pack-years of cigarette smoking had a significant increase in adipocytes, blood vessels and collagen deposit, as well as an increase in histopathological alterations. CONCLUSIONS: Pack-years of smoking was associated with DIAm injury. However, further clinicopathological studies are needed to confirm our findings.

Effects of aging on the secretory apparatus in the right atrial cardiomyocytes of rats.

The cardiac atria secrets polypeptide hormones usually called natriuretic peptides (NPs). These substances play a relevant role in the blood pressure regulation. The objective of the study was to estimate the effects of aging on the secretory apparatus of NPs in cardiomyocytes of the right atrium. Twenty male Wistar rats were studied: 10 young animals aged 3 months old (237 ±â€¯27 g; mean ±â€¯SD) and 10 old animals aged 20 months old (450 ±â€¯68 g; mean ±â€¯SD). The systolic blood pressure was verified instants before the moment of the euthanasia. Electron micrographs were prepared to quantify the area and density of the NP granules and the relative volumes of the endoplasmic reticulum, Golgi complex, and mitochondria. In addition, the number of pores per 10 µm of karyotheca was another variable evaluated. The significance of the results between the two groups evaluated was analyzed by the Student's t test (p < 0.05). The cardiomyocytes obtained from animals of the old group showed decreased in sectional area and density of secretory granules of NP and lower relative volume of endoplasmic reticulum, Golgi complex, and mitochondria compared with the young rats. Moreover, the quantitative density of nuclear pores was significantly lower compared with the youngers. CONCLUSION: Aging causes hypotrophy of the cardiomyocytes of right atrium, similar to what occurs in ventricular cardiomyocytes.

Evaluation of the Diaphragm Muscle Remodeling, Inflammation, Oxidative Stress and Vascularization in Smokers: An Autopsy Study.

BACKGROUND/AIMS: Cigarette smoking is a key factor in systemic inflammation and oxidative stress, and it has also been associated with the loss of muscle strength and an elevated risk of pulmonary diseases. Thus, this study aimed to analyze the effects of cigarette smoking on the diaphragm muscle structure of postmortem samples. METHODS: Immunohistochemical techniques were used for muscle remodeling (metalloproteinases 2 and 9), inflammation (cyclooxygenase-2), oxidative stress (8-hydroxy-2'-deoxyguanosine), and vascularization (vascular endothelial growth factor). Hematoxylin and eosin stain was used for histopathological analysis and Picrosirius stain was used to highlight the collagen fibers. RESULTS: Cigarette smokers had an increase of diaphragm muscle remodeling, oxidative stress, inflammation, and vascularization compared to non-smokers. CONCLUSION: Diaphragm muscle structure may be negatively affected by cigarette smoking.

Diaphragm muscle structure in the elderly: Findings from an autopsy study.

Sarcopenia is characterized as aging-related weakness and atrophy, which decreases the diaphragm force generating capacity leading to a decrease of expulsive non-ventilatory motor behaviors, which are critical for airway clearance. Thus, this study aimed to analyze the histopathology of the diaphragm in postmortem samples. Thirty individuals were included. Diaphragm samples were stained with hematoxylin and eosin for histopathological analysis. Picrosirius stain was used to highlight the collagen fibers. We observed a positive association between advancing age and histopathological findings in the diaphragm structure. We suggest that age is a key factor in increasing diaphragm muscle histopathology. However, further clinicopathological studies are needed to confirm our findings.

Ultrastructural effects of diabetes in the right atrium cardiomyocytes of elderly Wistar rats.

The present study aimed to evaluate the effects of diabetes on quantitative parameters of right atrial cardiomyocytes of elderly rats. Wistar rats (14 months of age) were divided into two groups: streptozotocin-diabetic rats (DG) and control rats (CG). The groups were sacrificed at 16 months. Ultrafine sections of the right atrium were analyzed by electron microscopy. In elderly diabetic animals, histograms of the frequency distribution of natriuretic peptides according to their size showed increased number of small and medium peptides in relation to large peptides, which increased its numerical density leading to a decrease in the mean diameter of both natriuretic peptides. However, elderly diabetic animals remained normotensive. No significant difference was observed between the groups for the volume density of mitochondria, endoplasmic reticulum, and Golgi apparatus. In conclusion, elderly diabetic rats showed increased functional activity of atrial cardiomyocytes with greater production of natriuretic peptides in association with a quantitative maintenance of cytoplasmic components.

Cigarette Smoking Impairs the Diaphragm Muscle Structure of Patients without Respiratory Pathologies: An Autopsy Study.

BACKGROUND/AIMS: Smoking is a major risk factor for several cardiovascular and pulmonary diseases, and it has also been associated with the loss of skeletal muscle mass and strength leading to sarcopenia. The aim of this is study is to analyze the effects of cigarette smoking on the diaphragm muscle histopathology of postmortem samples from patients without respiratory diseases. METHODS: Diaphragm samples were stained with hematoxylin and eosin for histopathological analysis. Picrosirius stain was used to highlight the collagen fibers. RESULTS: Cigarette smokers had an increase of histopathological alterations as abnormal cytoplasm, abnormal fiber size and shape, and central nucleus. Additionally, smokers had an increase of collagen fibers on diaphragm muscle. CONCLUSION: Smoking may influence in a negatively fashion the diaphragm musculature.

Glutamine supplementation influences the secretory apparatus in the right atrial cardiomyocytes of resistance trained aged rats / A suplementação de glutamina influencia o aparelho secretor dos cardiomiócitos do átrio direito de ratos idosos submetidos a treinamento de resistência / La suplementación de glutamina influye en el aparato secretor de los cardiomiocitos de la aurícula derecha de ratones viejos sometidos a entrenamiento de resistencia

Abstract We investigated the effects of glutamine supplementation on the secretory apparatus of natriuretic peptides in atrial cardiomyocytes of aged rats undergoing resistance training. Two groups of resistance-trained rats were studied: resistance trained, and resistance trained and supplemented with glutamine group. Both groups of rats were trained to climb a 1.1 m vertical ladder with weights tied to their tail. The cardiomyocytes from resistance trained and supplemented rats showed increased density and sectional area of natriuretic peptides granules, higher relative volumes of the mitochondria, endoplasmic reticulum, Golgi complex and nuclear euchromatin, and nuclear pore density compared with resistance trained rats. In conclusion, glutamine supplementation caused hypertrophy of the secretory apparatus in the cardiomyocytes of aged rats undergoing resistance training.

Resumo Foi investigado o efeito da suplementação de glutamina no aparelho secretor de peptídeos natriuréticos dos cardiomiócitos do átrio de ratos idosos submetidos a treinamento de resistencia. Foram estudados dois grupos: grupo de treinamento de resistência e grupo de treinamento de resistência suplementado com glutamina. Os ratos de ambos os grupos escalaram uma escada vertical de 1,1 m com pesos progressivamente maiores atrelados à cauda. Os resultados mostraram que os cardiomiócitos de ratos do grupo treinado e suplementado apresentaram maior densidade e maior área de seção de grânulos de peptideos natriuréticos, maiores volumes relativos de mitocôndrias, retículo endoplasmático, complexo de Golgi e eucromatina nuclear e maior densidade de poros nucleares em comparação com ratos do grupo de treinamento de resistência. Em conclusão, a suplementação com glutamina causou hipertrofia do aparelho secretor dos cardiomiócitos de ratos idosos submetidos ao treinamento de resistência.

Resumen Se investigó la influência de la suplementación de glutamina en el aparato secretor de péptidos natriuréticos de cardiomiocitos auriculares de ratones viejos sometidos a entrenamiento de resistencia. Se formaron dos grupos: grupo de entrenamiento de resistencia y grupo de entrenamiento de resistencia suplementado con glutamina. Los ratones escalaron una escalera vertical de 1,1 m con pesos atados a la cola. Los resultados mostraron que los cardiomiocitos de ratones del grupo de entrenamiento de resistência suplementado presentaron mayor densidad y área de sección de gránulos de péptidos natriuréticos, mayores volúmenes relativos de mitocondrias y de eucromatina nuclear y mayor densidad de poros nucleares en comparación con los ratones del grupo de entrenamiento de resistencia. En conclusión, la suplementación de glutamina causó hipertrofia del aparato secretor en los cardiomiocitos de ratones viejos sometidos al entrenamiento de resistencia.

Physical exercise alters hepatic morphology of low-density lipoprotein receptor knockout ovariectomized mice.

To explore the effects of physical exercise on the liver of animals in menopause, we analyzed the histomorphometric parameters of the hepatic tissue in ovariectomized and dyslipidemic female mice. The animals were distributed in six groups (n = 5): sedentary control (SC), sedentary ovariectomized control (SOC), trained ovariectomized control (TOC), sedentary LDL knockout (LDL-S), sedentary ovariectomized LDL knockout (LDL-SO), and trained ovariectomized LDL knockout (LDL-TO). At the end of the experiment, the liver and the visceral adipose tissue (VAT) of animals were removed for morphometric and stereological studies. In the LDL-S and LDL-SO animals, both sedentary, results showed reduction in the area (µm2) and major and minor diameters (µm) of hepatocytes and reduction in the portions of large hepatocytes, and increase in the percentage of Kupffer cells. The trained group showed a tendency of increase in the area and diameter and in the percentage of hepatocytes, as well significant reduction in the percentage of Kupffer cells and interstitial tissue. We suggested that training can prevent cell and tissue damage caused by the process of increase in hepatic fat, lipoperoxidation, and tissue inflammation in animals with privation of estrogen and dyslipidemia, apparently reflecting a better metabolic response of the hepatic tissue in organisms undergoing training.

Positive changes in femoral nerve morphometry in older rats following aerobic training.

The objective of the present study was to analyze alterations of the femoral nerve of aged rats subjected to aerobic training. Wistar rats (12-mo of age) were divided in to two groups: S group (sedentary) and T group (trained). The exercise protocol were 16 weeks long. The groups were sacrificed at 16 months. Ultrafine sections of the femoral nerve have been used. There was no change in the body weight between the groups. T group showed a significant increase in myelinated fiber area, axon diameter, myelin sheath thickness and myelin fiber number compared with sedentary controls. In exercised trained animals, histograms of the frequency distribution of myelinated axons according to their areas showed increased number of medium and large fibers in relation to small fibers, which decreased in number. Aerobic training animals, showed the distribution of myelinated fiber population according to their area being bimodal, with the distribution shifted to the right, indicating increased fiber area. The T group showed a percent damage of large myelinated fibers significantly lower compared to controls. No significant difference was observed between the groups for the g-ratio. The T group also showed a significant increase in the number of microtubules and neurofilaments in myelinated fibers, which was not observed in S group. In conclusion, aerobic training improves nerve structure without evidence of nerve damage and produces an attenuation on the modifications in femoral nerve that develop in old age.

Reference database of hematological parameters for growing and aging rats.

The normal hematological values in various phases of the rat life provide a valuable guide to researchers and could be useful for experimental works. However, database information available on the literature are incomplete. AIM: This study aimed to present normal hematological parameters of young and aged rats. METHODS: Male and female rats were distributed into seven experimental groups with 1, 2, 3, 6, 12, 18, and 24 months of age. Blood samples taken from the tails were analyzed. Normal hematological values were determined for each age group. RESULTS: Rats showed a progressive weight gain with advancing age, predominantly after 3 months of life. With advancing age, differences were found on hematological parameters: some of them showed a progressive rise with age and others did not. Hemoglobin levels and hematocrit did not change while the number of circulating red blood cells suffered slight increase. CONCLUSION: The present study determined the normal values for absolute and relative hematological parameters in Wistar rats from 2 to 24 months for male and female rats. The results can be used in studies of effects of aging, feeding, and medications on growing and aging rats.

Effects of resistance training on liver structure and function of aged rats.

The aging process may cause negative physiological changes. However, exercises as resistance training (RT) have been considered an important intervention to attenuate these changes. Additionally, liver plays an important role in blood glucose homeostasis in exercise. AIM: This study aimed to analyze the effects of RT on the liver components of aged animals. METHODS: Male Wistar rats were divided into two groups: 24 months' group (CONTROL); and group submitted to a progressive RT protocol for 16 weeks (EXERCISE). Both groups were sacrificed at 24 months. RESULTS: We observed a decrease in blood flow due to the practice of resistance exercises. Besides, our results showed that hepatic tissue plays an important role in glycemic homeostasis during RT. In addition, RT increased mitogen capacity of hepatocytes. CONCLUSIONS: Our study showed many implications for the knowledge about the effects of strength training on old animals' liver.

Balanced Caloric Restriction Minimizes Changes Caused by Aging on the Colonic Myenteric Plexus.

Aging can promote significant morphofunctional changes in the gastrointestinal tract (GIT). Regulation of GIT motility is mainly controlled by the myenteric neurons of the enteric nervous system. Actions that aim at decreasing the aging effects in the GIT include those related to diet, with caloric restriction (CR). The CR is achieved by controlling the amount of food or by manipulating the components of the diet. Therefore, the objective of this study was to evaluate different levels of CR on the plasticity of nicotinamide adenine dinucleotide phosphate- (NADPH-) reactive myenteric neurons in the colon of Wistar rats during the aging process using ultrastructural (transmission electron microscopy) and morphoquantitative analysis. Wistar male rats (Rattus norvegicus) were distributed into 4 groups (n = 10/group): C, 6-month-old animals; SR, 18-month-old animals fed a normal diet; CRI, 18-month-old animals fed a 12% CR diet; CRII, 18-month-old animals fed a 31% CR diet. At 6 months of age, animals were transferred to the laboratory animal facility, where they remained until 18 months of age. Animals of the CRI and CRII groups were submitted to CR for 6 months. In the ultrastructural analysis, a disorganization of the periganglionar matrix with the aging was observed, and this characteristic was not observed in the animals that received hypocaloric diet. It was observed that the restriction of 12.5% and 31% of calories in the diet minimized the increase in density and cell profile of the reactive NADPH neurons, increased with age. This type of diet may be adapted against gastrointestinal disturbances that commonly affect aging individuals.

Effects of testosterone administration on liver structure and function in aging rats.

Aging males have a decrease in testosterone levels, by which the testosterone treatment may influence in a negatively fashion the liver. AIM: This study aimed to analyze the effects of aging with or without testosterone administration on the liver components of animals. METHODS: Wistar rats were divided into three groups: 20 months' group (G20), 24 months' group (G24), group treated with testosterone for 16 weeks (GT). All groups were sacrificed at 24 months except for G20 that was sacrificed at 20 months. RESULTS: Aging and testosterone treatment alters the body weight (BW), liver weight (LW) and relative liver weight. Besides, testosterone increased the mitogen capacity of hepatocytes. Nonetheless, we reinforce the negative effects of testosterone on old animals' liver as chronic hepatic congestion and/or cholestasis. In addition, we observed that testosterone plays an important role on hepatic glycogen stores. CONCLUSIONS: Our study showed many implications for the knowledge about the effects of aging with or without testosterone administration on old animals' liver.

Caloric restriction minimizes aging effects on the femoral medial condyle.

This study aimed to analyze the effects of caloric restriction on aged femoral articular cartilage of Wistar rats. Three groups of eight animals each were considered: young (YC) and old (OC) control groups fed with a normal diet and old caloric restriction group (OCR) composed of 18-month-old animals fed with a 31% less caloric diet from 6-months of age. Articular cartilage was studied through morphometry and immunohistochemistry. Body mass was 12% less in the OCR group than in the OC group. The articular cartilage from OC rats show thinner medial condyles, fewer chondrocytes, smaller chondrocytes nuclear volume and, in both condyles, a predominance of collagen type II and less collagen density compared to both YC and OCR groups (p < .001). In contrast, OCR articular cartilage show thicker medial condyles, larger chondrocytes nuclear volume and increased collagen density compared to OC group (p < 0.001). We concluded that caloric restriction minimizes the effects of aging on medial condyles of the femoral articular cartilage.

MORPHOLOGICAL ADJUSTMENTS OF THE RADIAL NERVE ARE INTENSITY-DEPENDENT / AJUSTES MORFOLÓGICOS DO NERVO RADIAL SÃO DEPENDENTES DE INTENSIDADE / AJUSTES MORFOLÓGICOS DEL NERVIO RADIAL SON DEPENDIENTES DE INTENSIDAD

ABSTRACT Introduction: Peripheral nerve adaptation is critical for strength gains. However, information about intensity effects on nerve morphology is scarce. Objective: To compare the effects of different intensities of resistance training on radial nerve structures. Methods: Rats were divided into three groups: control (GC), training with 50% (GF1) and training 75% (GF2) of the animal’s body weight. The morphological analysis of the nerve was done by light and transmission electron microscopy. One-way ANOVA and the Tukey’s post hoc test were applied and the significance level was set at p≤0.05. Results: Training groups had an increase of strength compared to GC (p≤0.05). All measured nerve components (mean area and diameter of myelin fibers and axons, mean area and thickness of the myelin sheath, and of neurofilaments and microtubules) were higher in GF2 compared to the other (p≤0.05). Conclusion: Results demonstrated greater morphological changes on radial nerve after heavier loads. This can be important for rehabilitation therapies, training, and progression.

RESUMO Introdução: A adaptação dos nervos periféricos é fundamental para ganhos de força. No entanto, as informações relativas aos efeitos da intensidade sobre a morfologia do nervo são escassas. Objetivo: Comparar os efeitos de diferentes intensidades de treinamento de resistência sobre estruturas do nervo radial. Métodos: Os ratos foram divididos em três grupos: controle (GC) e treinamento com 50% (GF1) e 75% (GF2) do peso corporal do animal. A análise morfológica do nervo foi feita com microscopia óptica e eletrônica de transmissão. A one-way ANOVA e o teste post hoc de Tukey foram aplicados e o nível de significância foi estabelecido em p ≤ 0,05. Resultados: Os grupos treinamento tiveram aumento de força com relação ao GC (p ≤ 0,05). Todos os componentes medidos do nervo (área média e diâmetro de fibras de mielina e axônios, área média e espessura da bainha de mielina, neurofilamentos e microtúbulos) foram maiores no GF2 em comparação com os demais (p ≤ 0,05). Conclusão: Os resultados demonstraram maiores alterações morfológicas no nervo radial depois de cargas mais pesadas. Isso pode ser importante para terapias de reabilitação, treinamento e progressão.

RESUMEN Introducción: La adaptación de los nervios periféricos es fundamental para el aumento de fuerza. Sin embargo, la información sobre el efecto de la intensidad sobre la morfología del nervio es escasa. Objetivo: Comparar el efecto de diferentes intensidades de entrenamiento de resistencia en las estructuras del nervio radial. Métodos: Las ratas se dividieron en tres grupos: control (GC) y entrenamiento con 50% (GF1) y con 75% (GF2) del peso corporal del animal. El análisis morfológico del nervio se hizo con microscopía óptica y electrónica de transmisión. Se aplicaron la prueba ANOVA de una vía y la prueba post hoc de Tukey y el nivel de significación se fijó en p ≤ 0,05. Resultados: Los grupos de entrenamiento tuvieron aumento de la fuerza con respecto al grupo control (p ≤ 0,05). Todos los componentes medidos del nervio (área media y diámetro de las fibras de mielina y axones, área media y espesor de la vaina de mielina, neurofilamentos y microtúbulos) fueron mayores en GF2 en comparación con los otros grupos (p ≤ 0,05). Conclusión: Los resultados mostraron mayores cambios morfológicos en el nervio radial después de las cargas más pesadas. Esto puede ser importante para terapias de rehabilitación, entrenamiento y progresión.

Ultrasound evaluation of the morphometric patterns of lymph nodes of the head and neck in young and middle-aged individuals.

OBJECTIVE: To show the morphometric patterns of lymph nodes of the head and neck, evaluating their number, shape, dimensions, hilum, and cortex, through the use of ultrasound examination of the neck. MATERIALS AND METHODS: We analyzed 400 right and left lymph nodes in a group of 20 healthy young and middle-aged individuals of both genders. RESULTS: In the ultrasound examination, we observed the following lymph nodes: mastoid; parotid (superficial, extraglandular, and intraglandular); submandibular (preglandular, retroglandular, and intracapsular); submental; and cervical (anterior and posterior). Although some individuals had up to seven lymph nodes in the same region, most had only two to three per region. The smallest lymph node diameter observed was 0.4 cm, and the largest was 2.7 cm. Most lymph nodes showed an elongated or oval shape. Most of the lymph node hila were echogenic, although a few were hyperechoic. However, the cortex was clearly hypoechoic in all of the lymph nodes evaluated. CONCLUSION: Ultrasound examination of healthy individuals allowed the characteristics of the lymph nodes of the head and neck to be observed clearly, which could provide a basis for the analysis of patients with diseases of these lymph nodes.

OBJETIVO: Fornecer padrão morfoquantitativo ultrassonográfico dos linfonodos da cabeça e pescoço, mediante avaliação do seu número, forma, dimensões, hilo e córtex, como base para diagnóstico de alterações nestes parâmetros. MATERIAIS E MÉTODOS: Foram analisados 400 linfonodos dos lados direito e esquerdo de 20 indivíduos, homens e mulheres, jovens e de meia-idade. RESULTADOS: Os linfonodos observados no exame ultrassonográfico foram: mastóideos, parotídeos superficiais, parotídeos extraglandulares, parotídeos intraglandulares, submandibulares pré-glandulares, retroglandulares e intracapsulares, submentuais, cervicais anteriores e posteriores. Quanto ao número de linfonodos, alguns indivíduos apresentaram até sete em uma mesma região, mas a maioria apresentou de dois a três linfonodos por região. O menor diâmetro dos linfonodos foi 0,4 cm e o maior foi 2,7 cm. A maioria dos linfonodos apresentou forma alongada ou ovalada. O hilo dos linfonodos apresentou-se geralmente ecogênico e poucas vezes hiperecogênico. De modo geral, o córtex dos linfonodos mostrou-se muito pouco ecogênico. CONCLUSÃO: A ultrassonografia de indivíduos sadios permitiu uma clara observação das características dos linfonodos da região da cabeça e pescoço, que podem ser importantes para análise de pacientes portadores de afecções desses linfonodos.

EFFECTS OF AEROBIC TRAINING ON THE CARDIOMYOCYTES OF THE RIGHT ATRIUM OF MICE / EFEITOS DO TREINAMENTO AERÓBICO EM CARDIOMIÓCITOS DO ÁTRIO DIREITO DE CAMUNDONGOS / EFECTOS DEL ENTRENAMIENTO AERÓBICO EN CARDIOMIOCITOS DEL ATRIO DERECHO DE RATONES

ABSTRACT Introduction: Polypeptide hormones (natriuretic peptides, NPs) are secreted by the cardiac atria and play an important role in the regulation of blood pressure. Objective: To evaluate the effects of aerobic training on the secretory apparatus of NPs in cardiomyocytes of the right atrium. Methods: Nine-month-old mice were divided in two groups (n=10): control group (CG) and trained group (TG). The training protocol was performed on a motor treadmill for 8 weeks. Systolic blood pressure was measured at the beginning of the experiment (9 months of age) and at moment of the sacrifice (11 months of age). Electron micrographs were used to quantify the following variables: the quantitative density and area of NP granules, the relative volumes of the mitochondria, endoplasmic reticulum, and Golgi complex and the relative volume of euchromatin in the nucleus and the number of pores per 10 µm of the nuclear membrane. The results were compared by Student's t test (p< 0.05). Results: The cardiomyocytes obtained from TG mice showed increased density and sectional area of secretory granules of NP, higher relative volume of endoplasmic reticulum, mitochondria, and Golgi complex compared with the CG mice. Furthermore, the quantitative density of nuclear pores and the relative volume of euchromatin in the nucleus were significantly higher compared with the CG mice. Conclusion: Aerobic training caused hypertrophy of the secretory apparatus in the cardiomyocytes of right atrium, which could explain the intense synthesis of natriuretic peptides in trained mice with respect to the untrained mice.

RESUMO Introdução: Os hormônios polipeptídicos (peptídeos natriuréticos, PN) são secretados pelos átrios cardíacos e desempenham um papel importante na regulação da pressão arterial. Objetivo: Avaliar os efeitos do treinamento aeróbico sobre o aparelho secretor de PN nos cardiomiócitos do átrio direito. Métodos: Camundongos com nove meses de idade foram divididos em dois grupos (n = 10): grupo controle (GC) e grupo treinado (GT). O protocolo de treinamento foi realizado em esteira motorizada durante 8 semanas. A pressão sistólica dos animais foi medida no início do experimento (9 meses de idade) e no momento do sacrifício (11 meses). Foram usadas eletromicrografias para quantificar as seguintes variáveis densidade quantitativa e área dos grânulos de PN; volumes relativos (%) de mitocôndrias, retículo endoplasmático e aparelho de Golgi e o volume relativo de eucromatina no núcleo e o número de poros por 10 µm de membrana nuclear. Os resultados foram comparados pelo teste t de Student (p < 0,05). Resultados: Os cardiomiócitos obtidos dos camundongos GT apresentaram maior densidade e área seccional de grânulos secretórios de PN, aumento do volume relativo do retículo endoplasmático, das mitocôndrias e do complexo de Golgi, em comparação com os camundongos GC. Além disso, a densidade quantitativa dos poros nucleares e o volume relativo da eucromatina nuclear foram significantemente superiores em comparação com os camundongos GC. Conclusão: O treinamento aeróbico causou hipertrofia do aparelho secretor dos cardiomiócitos do átrio direito, o que poderia explicar a síntese intensa de peptídeos natriuréticos em camundongos treinados, quando comparados aos não treinados.

RESUMEN Introducción: Las hormonas polipeptídicas (péptidos natriuréticos, PN) son secretadas por las aurículas cardíacas y juegan un papel importante en la regulación de la presión arterial. Objetivo: Evaluar los efectos del entrenamiento aeróbico sobre el aparato secretor de PN en cardiomiocitos de la aurícula derecha. Métodos: Ratones de nueve meses de edad fueron divididos en dos grupos (n = 10): grupo control (GC) y grupo entrenado (GE). El protocolo de entrenamiento se realizó en cinta caminadora durante 8 semanas. La presión arterial sistólica se midió al inicio del experimento (9 meses de edad) y en el momento del sacrificio (11 meses de edad). Las electromicrografías se utilizaron para cuantificar las siguientes variables: la densidad cuantitativa y el área de gránulos de PN; los volúmenes relativos (%) de mitocondrias, del retículo endoplásmico y del aparato de Golgi y el volumen relativo de eucromatina en el núcleo y el número de poros por 10 µm de la membrana nuclear. Los resultados se compararon mediante la prueba t de Student (p < 0,05). Resultados: Los cardiomiocitos obtenidos de los ratones GE mostraron aumento de la densidad y del área seccional de gránulos secretorios de PN, aumento del volumen relativo de retículo endoplásmico, mitocondrias y aparato de Golgi en comparación con los ratones GC. Además, la densidad cuantitativa de los poros nucleares y el volumen relativo de la eucromatina nuclear fueron significativamente mayores en comparación con los ratones CG. Conclusión: El entrenamiento aeróbico causó hipertrofia del aparato secretor en los cardiomiocitos de la aurícula derecha, lo que podría explicar la intensa síntesis de péptidos natriuréticos en ratones entrenados con respecto a los ratones no entrenados.

Ultrasound evaluation of the morphometric patterns of lymph nodes of the head and neck in young and middle-aged individuals / Padrão ultrassonográfico dos linfonodos da cabeça e pescoço em indivíduos jovens e de meia-idade

Abstract Objective: To show the morphometric patterns of lymph nodes of the head and neck, evaluating their number, shape, dimensions, hilum, and cortex, through the use of ultrasound examination of the neck. Materials and Methods: We analyzed 400 right and left lymph nodes in a group of 20 healthy young and middle-aged individuals of both genders. Results: In the ultrasound examination, we observed the following lymph nodes: mastoid; parotid (superficial, extraglandular, and intraglandular); submandibular (preglandular, retroglandular, and intracapsular); submental; and cervical (anterior and posterior). Although some individuals had up to seven lymph nodes in the same region, most had only two to three per region. The smallest lymph node diameter observed was 0.4 cm, and the largest was 2.7 cm. Most lymph nodes showed an elongated or oval shape. Most of the lymph node hila were echogenic, although a few were hyperechoic. However, the cortex was clearly hypoechoic in all of the lymph nodes evaluated. Conclusion: Ultrasound examination of healthy individuals allowed the characteristics of the lymph nodes of the head and neck to be observed clearly, which could provide a basis for the analysis of patients with diseases of these lymph nodes.

Resumo Objetivo: Fornecer padrão morfoquantitativo ultrassonográfico dos linfonodos da cabeça e pescoço, mediante avaliação do seu número, forma, dimensões, hilo e córtex, como base para diagnóstico de alterações nestes parâmetros. Materiais e Métodos: Foram analisados 400 linfonodos dos lados direito e esquerdo de 20 indivíduos, homens e mulheres, jovens e de meia-idade. Resultados: Os linfonodos observados no exame ultrassonográfico foram: mastóideos, parotídeos superficiais, parotídeos extraglandulares, parotídeos intraglandulares, submandibulares pré-glandulares, retroglandulares e intracapsulares, submentuais, cervicais anteriores e posteriores. Quanto ao número de linfonodos, alguns indivíduos apresentaram até sete em uma mesma região, mas a maioria apresentou de dois a três linfonodos por região. O menor diâmetro dos linfonodos foi 0,4 cm e o maior foi 2,7 cm. A maioria dos linfonodos apresentou forma alongada ou ovalada. O hilo dos linfonodos apresentou-se geralmente ecogênico e poucas vezes hiperecogênico. De modo geral, o córtex dos linfonodos mostrou-se muito pouco ecogênico. Conclusão: A ultrassonografia de indivíduos sadios permitiu uma clara observação das características dos linfonodos da região da cabeça e pescoço, que podem ser importantes para análise de pacientes portadores de afecções desses linfonodos.