RESUMO
In spinal cord injury (SCI) there is damage to the nervous tissue, due to the initial damage and pathophysiological processes that are triggered subsequently. There is no effective therapeutic strategy for motor functional recovery derived from the injury. Several studies have demonstrated neurons growth in cell cultures on polymers synthesized by plasma derived from pyrrole, and the increased recovery of motor function in rats by implanting the polymer in acute states of the SCI in contusion and transection models. In the process of transferring these advances towards humans it is recommended to test in mayor species, such as nonhuman primates, prioritizing the use of non-invasive techniques to evaluate the injury progression with the applied treatments. This work shows the ability of diffusion tensor imaging (DTI) to evaluate the evolution of the SCI in nonhuman primates through the fraction of anisotropy (FA) analysis and the diffusion tensor tractography (DTT) calculus. The injury progression was analysed up to 3 months after the injury day by FA and DTT. The FA recovery and the DTT re-stabilization were observed in the experimental implanted subject with the polymer, in contrast with the non-implanted subject. The parameters derived from DTI are concordant with the histology and the motor functional behaviour.
RESUMO
Sarcopenia is a syndrome characterized by a progressive and generalized skeletal muscle mass and strength loss, as well as a poor physical performance, which as strongly been associated with aging. Sedentary lifestyle in the elderly contributes to this condition; however, physical activity improves health, reducing morbidity and mortality. Recent studies have shown that metformin (MTF) can also prevent muscle damage promoting muscular performance. To date, there is great controversy if MTF treatment combined with exercise training improves or nullifies the benefits provided by physical activity. This study is aimed at evaluating the effect of long-term moderate exercise combined with MTF treatment on body composition, strength, redox state, and survival rate during the life of female Wistar rats. In this study, rats performed moderate exercise during 20 of their 24 months of life and were treated with MTF for one year or for 6 months, i.e., from 12 to 24 months old and 18 to 24 months old. The body composition (percentage of fat, bone, and lean mass) was determined using a dual-energy X-ray absorption scanner (DXA), and grip strength was determined using a dynamometer. Likewise, medial and tibial nerve somatosensory evoked potentials were evaluated and the redox state was measured by HPLC, calculating the GSH/GSSG ratio in the gastrocnemius muscle. Our results suggest- that the MTF administration, both in the sedentary and the exercise groups, might activate a mechanism that is directly related to the induction of the hormetic response through the redox state modulation. MTF treatment does not eliminate the beneficial effects of exercise throughout life, and although MTF does not increase muscle mass, it increases longevity.
Assuntos
Metformina/farmacologia , Força Muscular/efeitos dos fármacos , Condicionamento Físico Animal/métodos , Sarcopenia/prevenção & controle , Fatores Etários , Animais , Feminino , Humanos , Masculino , Força Muscular/fisiologia , Ratos , Ratos Wistar , Sarcopenia/patologiaRESUMO
Osteopathologies are a result of advanced age and decreased bone density and represent a global health problem. It is therefore important to generate models for longitudinal studies of the pathophysiology in order to improve early diagnosis and develop preventive therapies. For this kind of research, the use of computed tomography (CT) to evaluate bone health offers advantages over other techniques since it provides more complete information. The aim of this prospective, pilot study was to obtain measurements of the left femur from a population in captivity of 32 rhesus monkeys (Macaca mulatta) in order to standardize the model for future research. Healthy subjects from 5 to 28 years old were chosen. Three groups with different ages were formed as follows: (1) 5-9 years, (2) 10-19 years, and (3) 20-28 years. Semi-automatic segmentation by threshold defined the regions of interest, which were subdivided in the range of 300-700 Hounsfield units (HU) for trabecular bone and >700 HU for cortical bone. Then, the proportional ratios of the volumes of trabecular bone and cortical bone were obtained. Significant differences (analysis of variance test) in the averages of Hounsfield units, cortical, and trabecular bone proportions from each age group proved that a decrease in bone density begins at approximately 20 years of age. The values presented here, as well as the method to obtain them from CT scans, can be used as a baseline in a primate model for long-term research in bone pathology diagnosis and treatment.
Assuntos
Densidade Óssea , Fêmur/fisiologia , Macaca mulatta/fisiologia , Tomografia Computadorizada por Raios X/veterinária , Animais , Projetos Piloto , Estudos Prospectivos , Tomografia Computadorizada por Raios X/métodosRESUMO
BACKGROUND: It has been widely documented that quadrupedal animals rarely display natural spontaneous scoliotic rachis deviations of the spinal column. The objective was to determine spinal deformities developed by geriatric monkeys of the Macaca mulatta species, by radiographical and tomographical studies of the vertebral column correlating morphological changes with altered physiological parameters and electrical neurosensorial conductivity of somatosensory-evoked potentials (SEPs). MATERIALS AND METHODS: A cohort of six geriatric monkeys was used: three non-scoliotic subjects and three monkeys with naturally acquired true scoliosis. RESULTS: Radiographic and tomographic studies depicted a thoracic curvature displaying a left-sided thoracic vertebral rotation. The evaluation of physiological parameters demonstrated significant differences in the respiratory rate, as it was observed for the diastolic blood pressures, which showed a decrease in the monkeys with scoliosis compared with healthy monkeys. Regarding the SEPs studies, the non-parametric test for independent samples Mann-Whitney U test displayed a significant difference observed at the left and right thoracic derivative in P1; while regarding the study of upper limbs, a significant difference was seen at the Erb's point derivative, left afferency in P1, showing in all the derivatives an increase in latency in monkeys with scoliosis versus monkeys in the control group. CONCLUSIONS: This study has demonstrated that quadrupedal animals can develop true scoliosis showing an analogous way to that occurring in humans.
Assuntos
Cardiopatias/veterinária , Macaca mulatta , Doenças dos Macacos/patologia , Doenças Respiratórias/veterinária , Escoliose/veterinária , Envelhecimento , Animais , Potenciais Somatossensoriais Evocados/fisiologia , Cardiopatias/etiologia , Doenças Respiratórias/etiologia , Escoliose/complicações , Escoliose/patologiaRESUMO
BACKGROUND: Current models of spinal cord injury (SCI) have been ineffective for translational research. Primate blunt SCI, which more closely resembles human injury, could be a promising model to fill this gap. METHODS: Graded compression SCI was produced by inflating at T9 an epidural balloon as a function of spinal canal dimensions in a non-uniform group of monkeys. RESULTS: Sham injury and cord compression by canal invasion of 50-75% produced minimal morpho-functional alterations, if at all. Canal invasion of 90-100% resulted in proportional functional deficits. Unexpectedly, these animals showed spontaneous gradual recovery over a 12-week period achieving quadruped walking, although with persistent absence of foot grasping reflex. Histopathology revealed predominance of central cord damage that correlated with functional status. CONCLUSIONS: Our preliminary results suggest that this model could potentially be a useful addition to translational work, but requires further validation by including animals with permanent injuries and expansion of replicates.
Assuntos
Modelos Animais de Doenças , Macaca mulatta , Compressão da Medula Espinal/patologia , Traumatismos da Medula Espinal/patologia , Medula Espinal/cirurgia , Cirurgia Veterinária/métodos , Animais , Feminino , Humanos , Locomoção , Masculino , Recuperação de Função Fisiológica , Reflexo , Compressão da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , CaminhadaRESUMO
In subclavian steal phenomenon (SSP), the subclavian artery develops a stenoocclusive disease proximal to the origin of the vertebral artery, leading to pronounced hemodynamic changes such as arterial flow reversal. Although SSP is a common echographic finding in humans, the phenomenon occurs only rarely in animals; consequently its physiologic features have not been reported previously. Here we describe the clinical and morphologic features of a spontaneous left SSP that was an incidental finding in an 18-y-old female rhesus macaque (Macaca mulatta). Our findings were documented through high-quality imaging studies obtained by using a computerized 3D tomography apparatus and clinical assessment of systolic and diastolic blood pressures.
Assuntos
Achados Incidentais , Doenças dos Macacos/diagnóstico , Doenças dos Macacos/fisiopatologia , Síndrome do Roubo Subclávio/veterinária , Angiografia , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Feminino , Macaca mulatta , Doenças dos Macacos/diagnóstico por imagem , Artéria Subclávia/diagnóstico por imagem , Artéria Subclávia/fisiopatologia , Síndrome do Roubo Subclávio/diagnóstico , Síndrome do Roubo Subclávio/fisiopatologia , Tomografia Computadorizada por Raios X , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/fisiopatologiaRESUMO
BACKGROUND: Somatosensory evoked potentials (SEPs) constitute a useful neurophysiologic tool commonly used to assess the functionality and developmental degree of the nervous system. OBJECTIVE: To analyze somatosensory pathways of the Macaca mulatta species throughout different ontogenetic statuses. METHODS: Twenty non-human primates were divided into five age-dependant groups. Recording of SEPs was executed by stimulation of lower limb at the tibial nerve and upper limb and recorded at the median nerve. RESULTS: Two wave series were observed for all groups for both limbs studied. Significant differences were found at the upper right limb at C4, C7 and also for the antecubital fossa site. The lower limbs showed a single significant right-wing deflection. CONCLUSIONS: Differences found in signals generated by the nervous system in response to somatosensory stimuli among the studied groups are thought to be developmental in origin, as the most remarkable deviations were seen in younger monkeys.
Assuntos
Potenciais Somatossensoriais Evocados , Macaca mulatta/fisiologia , Nervo Mediano/fisiologia , Nervo Tibial/fisiologia , Envelhecimento , Animais , Estimulação Elétrica , Feminino , MasculinoRESUMO
BACKGROUND: Somatosensory evoked potentials (SSEP) have been described as excellent indicators of the degree of medullar injury in degenerative and metabolic diseases of the central nervous system (CNS). The prevalence of neural tube defects (NTD) is 6 cases/10,000 live newborns worldwide. It is thought that genetic as well as environmental factors contribute to the etiology of NTD. The objective of this study was to analyze and compare the latencies obtained by means of SSEP in a clinically healthy monkey vs. rhesus monkeys with intrauterine surgery in order to simulate surgically the neural tube defect (myelomengocele) by performing an intrauterine laminectomy and in which later the defect was corrected. METHODS: This study was performed using three non-human primates of the Macaca mulatta species. There were practice intrauterine surgeries in two monkeys to simulate the neurological defect produced by myelomeningocele, using the third monkey as control. For statistical methodology four monkeys were used. They were born by natural birth without any surgical manipulation. With the cesarean-obtained products, stimulation was performed of the tibial and median nerve. RESULTS: We observed that the hind limbs were the most affected, in particular, the left afferent of the monkey. The spinal cord was exposed to amniotic fluid, and there were no significant differences in the forelimbs. CONCLUSIONS: The use of SSEP provides valuable information regarding preservation of sensorial functions in a variety of experimental neurological abnormalities.
Assuntos
Potenciais Somatossensoriais Evocados , Terapias Fetais , Implantes Experimentais , Laminectomia/métodos , Nervo Mediano/fisiopatologia , Meningomielocele/fisiopatologia , Nervo Tibial/fisiopatologia , Animais , Cesárea , Parto Obstétrico , Modelos Animais de Doenças , Feminino , Perna (Membro)/inervação , Macaca mulatta , Meningomielocele/embriologia , Meningomielocele/etiologia , Meningomielocele/cirurgia , Gravidez , Tempo de Reação , Telas CirúrgicasRESUMO
PURPOSE: Evaluate the anesthetic management in intrauterine surgery to induce myelomeningocele in non human primates Macaca mulatta. METHODS: A total of nine fetuses had intrauterine surgery; laminectomy was performed on them in L5 and L6. The studied variables were: maternal death, fetus death, cardiac frequency, respiratory frequency, arterial pressure, temperature, and oxygen saturation. RESULTS: No maternal or fetal deaths occurred; the only variable that was reported below the normal ranges was temperature. CONCLUSION: No maternal or fetal deaths occurred; the only variable that was reported below the normal ranges was temperature.
OBJETIVO: Avaliar o manejo anestésico em cirurgia intra-uterina para induzir mielomeningocelo em primatas não humanos, Macaca mulatta. MÉTODOS: Operaram-se um total de nove fetos in útero que foram submetidos à laminectomia em L5 e L6. As variáveis a estudar foram mortes maternas ou fetais, freqüência cardíaca e respiratória, pressão arterial, temperatura e saturação de oxigênio. RESULTADOS: Não se apresentaram mortes maternas ou fetais, a temperatura se manteve abaixo dos 36°C, não tendo repercussões no bem-estar dos macacos. CONCLUSÃO: Não ocorreu nenhum óbito materno ou fetal, sendo que a única variável abaixo do normal foi a temperatura.
Assuntos
Animais , Feminino , Gravidez , Anestesia/métodos , Feto/cirurgia , Laminectomia/métodos , Meningomielocele , Pressão Sanguínea/fisiologia , Temperatura Corporal/fisiologia , Frequência Cardíaca/fisiologia , Estudos Longitudinais , Macaca mulatta , Modelos Animais , Meningomielocele/etiologia , Taxa Respiratória/fisiologia , Fatores de TempoRESUMO
PURPOSE: Evaluate the anesthetic management in intrauterine surgery to induce myelomeningocele in non human primates Macaca mulatta. METHODS: A total of nine fetuses had intrauterine surgery; laminectomy was performed on them in L5 and L6. The studied variables were: maternal death, fetus death, cardiac frequency, respiratory frequency, arterial pressure, temperature, and oxygen saturation. RESULTS: No maternal or fetal deaths occurred; the only variable that was reported below the normal ranges was temperature. CONCLUSION: No maternal or fetal deaths occurred; the only variable that was reported below the normal ranges was temperature.(AU)
OBJETIVO: Avaliar o manejo anestésico em cirurgia intra-uterina para induzir mielomeningocelo em primatas não humanos, Macaca mulatta. MÉTODOS: Operaram-se um total de nove fetos in útero que foram submetidos à laminectomia em L5 e L6. As variáveis a estudar foram mortes maternas ou fetais, freqüência cardíaca e respiratória, pressão arterial, temperatura e saturação de oxigênio. RESULTADOS: Não se apresentaram mortes maternas ou fetais, a temperatura se manteve abaixo dos 36ºC, não tendo repercussões no bem-estar dos macacos. CONCLUSÃO: Não ocorreu nenhum óbito materno ou fetal, sendo que a única variável abaixo do normal foi a temperatura.(AU)
Assuntos
Animais , Anestesia/métodos , Anestesia/tendências , Anestesia/veterinária , Laminectomia/métodos , Laminectomia/tendências , Laminectomia/veterinária , Meningomielocele/veterinária , Macaca mulatta , PrenhezRESUMO
PURPOSE: Evaluate the anesthetic management in intrauterine surgery to induce myelomeningocele in non human primates Macaca mulatta. METHODS: A total of nine fetuses had intrauterine surgery; laminectomy was performed on them in L5 and L6. The studied variables were: maternal death, fetus death, cardiac frequency, respiratory frequency, arterial pressure, temperature, and oxygen saturation. RESULTS: No maternal or fetal deaths occurred; the only variable that was reported below the normal ranges was temperature. CONCLUSION: No maternal or fetal deaths occurred; the only variable that was reported below the normal ranges was temperature.