RESUMO
Severe nerve injuries can be treated with electrical stimulation and stem cell therapies, but little is known about the potential benefits of combining these two treatments. In an effort to investigate this combination, we conducted a study to evaluate the effectiveness of electrical stimulation and Schwann-like cell transplantation in female Wistar albino rats. Our study consisted of five groups of rats: a sham group, an injury group, an electrical stimulation group, a Schwann-like cell group, and a combination group. The experimental groups received electrical stimulation, Schwann-like cell transplantation, or both. The animals sciatic function index was evaluated during a 6-week recovery period, and nerve conduction velocity, wet muscle mass, and nerve tissues were also analyzed. The results of the study showed that all experimental groups had a faster functional recovery compared to the injury group, although the difference between groups was not statistically significant. Both the combination group and the Schwann-like cell transplantation group had a higher nerve conduction velocity compared to the other experimental groups. However, there was no significant difference between the combination and Schwann-like cell transplantation groups. Nonetheless, histological analysis showed a better axonal reorganization in the combination group. The study provides preliminary evidence of the potential benefits of combining electrical stimulation and Schwann-like cell transplantation in treating severe nerve injuries. However, further studies with larger sample sizes are needed to confirm these findings and optimize the treatment parameters.
Assuntos
Traumatismos dos Nervos Periféricos , Neuropatia Ciática , Ratos , Feminino , Animais , Nervo Isquiático , Ratos Wistar , Neuropatia Ciática/terapia , Traumatismos dos Nervos Periféricos/terapia , Estimulação Elétrica , Regeneração Nervosa/fisiologia , Células de SchwannRESUMO
A growing number of studies in humans have linked chronic stress, particularly during early life, to telomere shortening and increased oxidative stress. The effect of stress on telomerase activity, however, is understudied. Given the importance of telomere attrition in a wide range of diseases and immunosenescence, further research to elucidate the mechanisms by which stress alters telomere dynamics is required. However, animal studies are lacking, and it is not clear whether widely used stress models reliably mimic the accelerated telomere shortening observed humans. To this end, we evaluated the effect of maternal separation with early weaning (MSEW) on telomere length, telomerase activity, and oxidative load in rats. A total of 45 animals were used, (17 control: 3 males and 11 females and 28 MSEW: 11 males, 17 females), which were then sacrificed one year after birth. Importantly, we determined that telomerase activity measured in plasma was significantly decreased in the MSEW group, along with a non-significant reduction in telomere length from whole blood cells. We also examined the levels of three oxidative markers: plasma malondialdehyde, glutathione in erythrocytes, and plasma catalase activity. Malondialdehyde was found to be elevated in the plasma, indicating increased lipid peroxidation. Interestingly, while the antioxidant glutathione was upregulated, catalase activity remained unchanged. Our findings indicate that the rat MSEW model induces chronic changes to telomere dynamics and oxidative load and can capitulate long term aspects of human childhood stress.
Assuntos
Telomerase , Animais , Feminino , Privação Materna , Estresse Oxidativo , Ratos , Estresse Psicológico , Telomerase/genética , Telomerase/metabolismo , Encurtamento do TelômeroRESUMO
Background: Development of methods to accelerate nerve regeneration in peripheral nerve damage is important. Electroacupuncture is a new therapeutic method that combines traditional acupuncture with modern electrotherapy. Melatonin has been shown to reduce nerve damage. Objectives: In this study, we aimed to determine and compare the therapeutic effects of electroacupuncture and melatonin on rat sciatic nerve injury. Methods: A total of 56 adult male Wistar Albino rats were divided into four study groups with 14 animals in each group: intact control (group I), subcutaneous saline (group II), subcutaneous melatonin (group III), and electroacupuncture (group IV). Surgical procedure including unilateral (right) sciatic nerve injury was applied to groups II, III, and IV. Saline and melatonin started immediately after surgery for six weeks, while electroacupuncture was given two weeks after surgery for 3 weeks. Functional and histological assessments were used as outcome measurements. Results: Sciatic nerve damage caused a significant decrease in nerve conduction velocity. Both electroacupuncture treatment and melatonin treatment significantly increased the nerve conduction velocity. Both sciatic functional recovery and histological regeneration were faster in these treatment groups compared to the saline. However, no significant difference was observed between the two treatment groups. Conclusion: Electroacupuncture and melatonin are promising alternative treatment strategies for peripheral nerve damage and can be examined in detail in future studies.
Assuntos
Eletroacupuntura , Melatonina , Animais , Masculino , Melatonina/farmacologia , Melatonina/uso terapêutico , Regeneração Nervosa , Ratos , Ratos Wistar , Nervo IsquiáticoRESUMO
AIM: To investigate the effects of systemic application of Theranekron on peripheral nerve healing after compression type peripheral nerve injury. MATERIAL AND METHODS: Twenty-one female Wistar albino rats were randomly divided into 3 groups (n=7): Control (C), injury (I), and Theranekron (T). The right sciatic nerves of rats in the I and T groups were compressed via an aneurysm clip for 5 minutes and 0.3 ml Theranekron D6 was applied via subcutaneous administration once a week in the T group for a total period of four weeks. Nerve conduction velocity and proximal and distal latency of the rats were measured at the end of day 30. The right sciatic nerves of the rats were then removed and myelin damage grading, axon counting, fibrosis assessment, caspase-3, and NF-kB immunochemical staining were performed. The data were analysed statistically and a p value of less than 0.05 was considered to be significant. RESULTS: Axonal degeneration, vacuolization and myelin destruction were found to be markedly greater in group T. Fibrosis and caspase-3 immunoreactivity were less intense in group T. There was a statistically significant difference in the electrophysiological results of groups I and T. However, there were no statistically significant differences in axon number and NF-kB immunochemical evaluation of groups I and T. CONCLUSION: The findings of this study show that Theranekron decreases axonal and myelin damage after sciatic nerve injury and that this neuroprotective effect of Theranekron can be attributed to its anti-inflammatory effect on pro-inflammatory cytokine levels.
Assuntos
Regeneração Nervosa/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Traumatismos dos Nervos Periféricos , Venenos de Aranha/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Axônios/efeitos dos fármacos , Feminino , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Nervo Isquiático/lesõesRESUMO
OBJECTIVES: This paper presents the design and construction of a viable pupillometer system and demonstrates its merits with extensive validation tests. MATERIALS AND METHODS: A web camera was modified by removing its infrared filter and mounted on a chin rest. Light emitting diodes (LEDs) operating at infrared and visible spectra were integrated to provide background and light stimulus, respectively. The LEDs were controlled by a microprocessor board. Stimulation was presented using a periodic paradigm with variable period and duty cycle. Videos of both pupils were recorded at 30 frames/second and processed offline using software developed in-house. The overall system was validated with data gathered from individuals with healthy vision under different stimulation paradigms. Temporal variations in pupil size were determined and analyzed statistically. RESULTS: The analysis revealed that the pupil sizes were accurately measured from the video frames provided that reflections from both infrared and visible lights remain outside the pupil. The system achieved moderate to excellent repeatability scores (87.8 and 86.8% for short 1 second and long 2 second pulses, respectively), which demonstrated its effectiveness and confirmed that it can be used reliably as a pupillometer. CONCLUSION: The proposed pupillometer system produces useful, quantitative data characterizing pupillary light response. However, further development and implementation are needed to potentially turn it into a low-cost alternative for other studies involving the autonomic nervous system, cognitive function, drug metabolism, pain response, psychology, fatigue, and sleep disorders.
RESUMO
In the past decade, extensive research on dielectric properties of biological tissues led to characterization of dielectric property discrepancy between the malignant and healthy tissues. Such discrepancy enabled the development of microwave therapeutic and diagnostic technologies. Traditionally, dielectric property measurements of biological tissues is performed with the well-known contact probe (open-ended coaxial probe) technique. However, the technique suffers from limited accuracy and low loss resolution for permittivity and conductivity measurements, respectively. Therefore, despite the inherent dielectric property discrepancy, a rigorous measurement routine with open-ended coaxial probes is required for accurate differentiation of malignant and healthy tissues. In this paper, we propose to eliminate the need for multiple measurements with open-ended coaxial probe for malignant and healthy tissue differentiation by applying support vector machine (SVM) classification algorithm to the dielectric measurement data. To do so, first, in vivo malignant and healthy rat liver tissue dielectric property measurements are collected with open-ended coaxial probe technique between 500 MHz to 6 GHz. Cole-Cole functions are fitted to the measured dielectric properties and measurement data is verified with the literature. Malign tissue classification is realized by applying SVM to the open-ended coaxial probe measurements where as high as 99.2% accuracy (F1 Score) is obtained.