A dual-mode neurostimulation approach to enhance athletic performance outcome in experienced taekwondo practitioners.

Transcranial Direct Current Stimulation (tDCS) is a growing empirical approach to improve athletic performance. Some recent studies have investigated the effects of transcutaneous spinal direct current stimulation (tsDCS) on the motor performance such as reaction time. TDCS and tsDCS can lead to alteration of the spontaneous neural activity, and the membrane potentials of motor neurons in cerebral cortex and spinal interneurons, respectively. Given the paucity of experimental studies on the non-invasive brain stimulation in the field of sports neuroscience, especially martial sports, the present study aimed at investigating the effects of neurostimulation in potentiating the motor and cognitive functions in experienced taekwondo practitioners. The study sample included 15 experienced male taekwondo players who received real or sham direct current stimulation on the primary motor cortex (M1) and the lumbar spinal segment (T12-L2) over two sessions, 72 h apart. Next, the performance of the participants was evaluated through a simulation of taekwondo exercise directly after the sham and real sessions. Moreover, a cognitive platform (CBS: Cambridge Brain Science) was used to investigate the participants' cognitive profile in each instance. Unlike sham stimulation, real tDCS was associated with improved selective attention and reaction time in both in the simulated task performance and cognitive examination. The concurrent cortical and trans-spinal tDCS was found to improve selective attention (31% performance improvement) (P < 0.0001) [EFFECT SIZE; 1.84]. and reduce reaction time (4.7% performance improvement) (P < 0.0001) [EFFECT SIZE; 0.02]. Meanwhile, the intervention failed to leave a significant change in cognitive functions evaluated through CBS (P > 0.05). As informed by our results, the present dual-mode neurostimulation could improve motor functions potentially through the effect of tsDCS over the spinal interneurons and tDCS over the primary motor cortex. Likewise, our findings suggested an improved performance in simulated taekwondo task after real- but not sham-stimulation. This study paves the way for designing neurostimulation protocols to improve the performance of professional athletes, namely martial art practitioners, including their accuracy and velocity of reactions. Such positive effects of neuostimulation in athletic performance as demonstrated in this research and similar reports are expected to enhance the athletes' success in professional competitions.

Pure PBL, Hybrid PBL and Lecturing: which one is more effective in developing cognitive skills of undergraduate students in pediatric nursing course?

BACKGROUND: Nursing education in Iran has conventionally focused on lecture-based strategies. Improvements in teaching and learning over the years have led to an expansion of the pedagogies available to educators. Likewise, there has been a suggestion for a move toward more learner-centered teaching strategies and pedagogies that can result in improvement in learning. This study was undertaken to investigate the effects of Problem-Based Learning in developing cognitive skills in learning Pediatric Nursing among university students. METHODS: In this quasi-experimental, posttest-only nonequivalent control group design, the subjects were undergraduate students who had enrolled in Pediatric Nursing II at Islamic Azad University in Iran. The experiment was conducted over a period of eight weeks, one two-hour session and two two-hour sessions. Two experimental groups, Pure Problem-Based Learning (PPBL) and the Hybrid Problem- Based Learning (HPBL), and one Lecturing or Conventional Teaching and Learning (COTL) group were involved. In the PPBL group, PBL method with guided questions and a tutor, and in the HPBL group, problem-based learning method, some guided questions, minimal lecturing and a tutor were used. The COTL group, however, underwent learning using conventional instruction utilizing full lecture. The three groups were compared on cognitive performances, namely, test performance, mental effort, and instructional efficiency. Two instruments, i.e., Pediatric Nursing Performance Test (PNPT) and Paas Mental Effort Rating Scale (PMER) were used. In addition, the two-Dimensional Instructional Efficiency Index (IEI) formula was utilized. The statistical analyses used were ANOVA, ANCOVA, and mixed between-within subjects ANOVA. RESULTS: Results showed that the PPBL and HPBL instructional methods, in comparison with COTL, enhanced the students' overall and higher-order performances in Pediatric Nursing, and induced higher level of instructional efficiency with less mental effort (p < 0.005). Although there was no significant difference in lower-order performance among the groups during the posttest (p = 0.92), the HPBL group outperformed the COTL group on the delayed posttest (p = 0.028). CONCLUSIONS: It may be concluded that both forms of PBL were effective for learning Pediatric Nursing. Moreover, PBL appears to be useful where there are shortages of instructors for handling teaching purposes.

Epstein-Barr virus hepatitis can cause transient hepatopulmonary syndrome.

INTRODUCTION: Hepatopulmonary syndrome is commonly seen in the patients with chronic liver disease. Acute liver diseases are rarely associated with HPS. We have reported here a case of Transient HPS caused by Epstein-Barr virus hepatitis. CASE REPORT: The patient was a 31 years old man that came to hospital due to RUQ pain and yellowish skin. In examination the patient was tachypnic and O2 saturation was 71% with prominent JVP. ver enzyme and bilirubin were high. All viral hepatitis was negative except anti viral capsid antigen-antibody of EBV. In Blood gas PaO2 was 54 mmHg, O2 saturation 73% and alveolar-arterial gradient was 18 mmHg. Stress Echocardiography with saline injection reported pulmonary arterial pressure 32 cmHg with delayed opacification of left atrium. CONCLUSION: transient HPS can be manifestation in the acute hepatitis caused by EBV infection.

Case Report: Pulmonary and Liver Sarcoidosis Suspected of Metastasis.

Introduction: Sarcoidosis is a granulomatous disease with unknown cause that can vary from an asymptomatic condition. Almost half of the patients with sarcoidosis have no symptoms. In this article, we describe a sarcoidosis patient with lung and liver engagement; it may be confused with metastasis. Case report: A 39-year-old man, known as hypothyroidism who had come to the emergency ward with dyspnea and coughing after exposure to detergents in a closed environment A 39-year-old man, known as hypothyroidism who had come to the emergency ward with dyspnea and coughing after exposure to detergents in a closed environment. The patient smoked for 10 years (3 pack/year). No other findings were found in clinical examinations except for wheezing in the right lung. The patient's chest radiography was shown a mass. For further investigation, spiral CT scan was performed. Large lymph nodes on the right side of the trachea, measuring about 23 mm and a mass of 70 × 77 mm in the vicinity of the right lung hilum and a hypodense nodule in the posterior part of the liver with malignancy suspicious were reported. After several biopsy results was shown chronic granulomatous inflammation, the most important differential diagnosis is tuberculosis (TB) and sarcoidosis. Sputum smear, culture, and PCR were performed for tuberculosis. Also, the level of angiotensin-converting enzyme (ACE) was measured for sarcoidosis. the results ruled out TB and shown a higher level of ACE (ACE = 88).After diagnosis treatment started with prednisolone. Now, the patient is in the follow- up. Conclusion: In hilar lymphadenopathy of lung sarcoidosis is the importance differential diagnosis that should be considered.

The Effects of L-arginine on the Hippocampus of Male Rat Fetuses under Maternal Stress.

INTRODUCTION: Prenatal stress has deleterious effects on the development of the brain and is associated with behavioral and psychosocial problems in childhood and adulthood. This study aimed to determine the protective effect of L-arginine on fetal brain under maternal stress. METHODS: Twenty pregnant Wistar rats (weighting 200-230 g) were randomly divided into 4 groups (n=5 for each group). The first nonstress and stress groups received 2 mL of normal saline and the other nonstress and stress two groups received L-arginine (200 mg/kg, IP) from their 5(th) to 20(th) days of pregnancy. The pregnant rats were killed on 20(th) day and the brain fetuses removed and prefrontal cortical thickness, total neurons in the prefrontal cortex and in the areas of CA1, CA2, and CA3 of the hippocampus were measured and counted. Nitrite levels in the brain were measured as an indicator for nitric oxide (NO) level. RESULTS: There was a significant decrease of mean number of pyramidal cells in the CA1 in prenatal stress group compared to nonstress and nonstress plus arginine groups. The NO level in brain tissue increased significantly in the stress plus arginine (3.8±0.4 nmol/mg) and in nonstress rats (2.9±0.3 nmol/mg) compared to the stress group (1.8±0.1 nmol/mg). Prefrontal cortical thickness decreased significantly in stress rats (1.2±0.09 mm) compared to the nonstress plus arginine (1.7±0.15 mm) and nonstress (1.6±0.13 mm) groups. DISCUSSION: Results indicated that prenatal stress could lead to neurodegeneration of hippocampus and prefrontal cortex of rat fetuses. L-arginine as a precursor of NO synthesis had neuroprotective effect during prenatal stress and could be used an effective treatment for stress.

Age-associated changes on axonal regeneration and functional outcome after spinal cord injury in rats.

This study was conducted to evaluate the association between aging and regenerative potential of spinal cord injury. Three groups of male Sprague-Dawley rats, including young (40 days), mature (5-6 months) and old (28-29 months) were spinally hemisected at the L1 level. The locomotor performance was assessed weekly for eight weeks after lesion using locomotors' rating scale developed by Basso, Bresnahan and Beattie (BBB). In the tracing study, retrograde labeled neuron was counted in the lateral vestibular nucleus for axonal regeneration. From 4-8 weeks, the functional recovery of the young and mature age rats was significantly increased in comparison to the old age group. At 8 weeks, young and mature animals achieved a plateau score of (mean ± SD), 17 ± 1.47 and 16.8 ± 0.70 respectively, and the old rats reached an average score of 13.8±1.63 (P<0.05). The mean number of labeled neurons in the vestibular nucleus in the young group (mean ± SD): 32.05 ± 1.03 increase significantly compared to the older age group 5.01 ± 1.31 (P<0.05). Current findings suggest that axonal repair and functional improvement decrease in aged animals after partial spinal cord injury. Thus, the aging process may affect the regenerative capacity of the injured central nervous system, and axonal regeneration is age dependent.

Mouse Oocytes and Embryos Cryotop-vitrification Using Low Concentrated Solutions: Effects on Meiotic Spindle, Genetic Material Array and Developmental Ability.

OBJECTIVE(S): The examination of the possibility of applying lower CPA- concentrations and obtaining the similar results to those using higher concentrations; as it is shown, the toxicity of the CPAs used in vitrification approach will diminish. MATERIALS AND METHODS: Following vitrification/warming, oocytes were subjected to PZD/ICSI. SRs, FRs, and DRs were recorded. SRs and DRs of the embryos were monitored after vitrification/warming. IHC studies were done. Data were analyzed in comparison to the data of Exp. (experimental groups) applying 1.5 M CPA- concentrations (largely-used concentration). RESULTS: The data of oocytes exposed to 1.25 M concentrated CPAs were in consistency with those exposed to 1.5 M and fresh oocytes in terms of SRs, FRs and DRs. Normal spindle and chromatin configuration is in consistence between the two experimental groups, but lower in comparison with control group. The lower the concentrations were, the less SRs, FRs, DRs were. Also, spindle organizations were more normal in comparison with the experimental groups as the concentrations decreased. The results of DRs for embryos which were exposed to 1.25 and 1.0 M concentrated CPAs were close to those vitrified with 1.5 M and fresh embryos but IHC observations in the three Exp. were significantly lower than those of fresh embryos. The results of 7.5 M concentrated CPAs solutions were significantly lower than those of the control group 1.5, 1.25 and 1.0 M treated. CONCLUSIONS: Vitrification by cryotop technology using minimal volume approach increases both cooling and warming rates, therefore, the CPAs limited reduction to 1.25 and 1.0 M instead of using 1.5 M for oocytes and embryos cryotop-vitrification procedure, may be a slight adjustment.

Mouse Oocytes and Embryos Cryotop-vitrification Using Low Concentrated Solutions: Effects on Meiotic Spindle, Genetic Material Array and Developmental Ability.

OBJECTIVE(S): The examination of the possibility of applying lower CPA- concentrations and obtaining the similar results to those using higher concentrations; as it is shown, the toxicity of the CPAs used in vitrification approach will diminish. MATERIALS AND METHODS: Following vitrification/warming, oocytes were subjected to PZD/ICSI. SRs, FRs, and DRs were recorded. SRs and DRs of the embryos were monitored after vitrification/warming. IHC studies were done. Data were analyzed in comparison to the data of Exp. (experimental groups) applying 1.5 M CPA- concentrations (largely-used concentration). RESULTS: The data of oocytes exposed to 1.25 M concentrated CPAs were in consistency with those exposed to 1.5 M and fresh oocytes in terms of SRs, FRs and DRs. Normal spindle and chromatin configuration is in consistence between the two experimental groups, but lower in comparison with control group. The lower the concentrations were, the less SRs, FRs, DRs were. Also, spindle organizations were more normal in comparison with the experimental groups as the concentrations decreased. The results of DRs for embryos which were exposed to 1.25 and 1.0 M concentrated CPAs were close to those vitrified with 1.5 M and fresh embryos but IHC observations in the three Exp. were significantly lower than those of fresh embryos. The results of 7.5 M concentrated CPAs solutions were significantly lower than those of the control group 1.5, 1.25 and 1.0 M treated. CONCLUSIONS: Vitrification by cryotop technology using minimal volume approach increases both cooling and warming rates, therefore, the CPAs limited reduction to 1.25 and 1.0 M instead of using 1.5 M for oocytes and embryos cryotop-vitrification procedure, may be a slight adjustment.

The effects of cyclosporin-A on functional outcome and axonal regrowth following spinal cord injury in adult rats.

It has been shown that the immunophilin ligands have the special advantage in spinal cord repair. In this study, the effects of cyclosporine A (CsA) on functional recovery and histological outcome were evaluated following spinal cord injury in rats. After spinal cord hemisection in thirty six adult female Sprague-Dawley rats (200- 250 g), treatment groups received CsA (2.5 mg/kg i.p.) at 15min and 24h after lesion (CsA 15min group and CsA 24h group) daily, for 8 weeks. Control and sham groups received normal saline and in sham operated animals the spinal cord was exposed in the same manner as treatment groups, but was not hemisected. Hindlimb motor function was assessed in 1, 3, 5 and 7 weeks after lesion, using locomotive rating scale developed by Basso, Bresnahan and Beattie (BBB). Motor neurons were counted within the lamina IX of ventral horn and lesion size was measured in 5 mm of spinal lumbar segment with the epicenter of the lesion site. The mean number of motor neurons and the mean BBB scale in 3, 5 and 7 weeks in CsA 15min groups significantly increased compared to the control group. Although, the lesion size reduced in rats with CsA treatment compared to the control group, no significant difference was observed. Thus, it can be concluded that CsA can improve locomotor function and histological outcome in the partial spinal cord injury.

The effect of hydro alcoholic extract of Juglans regia leaves in streptozotocin-nicotinamide induced diabetic rats.

Phytotherapy has been achieved to maintain glycemic control in patients with diabetes mellitus. The present study was conducted to evaluate the antihyperglycemic properties of the Juglans regia leaf extract in streptozotocin-nicotinamide induced diabetic rats. Nicotinamide was injected intraperitonealy (i.p.) 15 min before the injection of Streptozotocin (i.p.). One week after induction of diabetes, oral treatment started with extract of Juglans regia and Metformin and continued for 4 weeks. Fasting blood sugar, body weight, serum lipids and insulin level were measured in different groups. A significant reduction of glucose, HbA1c, total cholesterol and serum triglycerides were detected after 4 weeks in rats treated with Juglans regia leaves compared to the control groups. Thus, Juglans regia extract treatment showed potential hypoglycemic and hypolipidemic effects in type 2 diabetic rats.

Ultrastructural changes in spinal motoneurons and locomotor functional study after sciatic nerve repair in conduit tube.

OBJECTIVES: Motor deficit and neuron degeneration is seen after nerve transection. The aim of this study is to determine whether a poled polyvinelidene fluoride (PVDF) tube with other supportive strategies can protect the neuronal morphology and motor function after sciatic nerve transaction in rats. MATERIALS AND METHODS: After transection of the left sciatic nerve in 60 male Wistar rats (200-250 g), the epineural group was sutured end to end. In the autograft rats, a 10 mm piece of sciatic nerve was rotated 180 °C and sutured back into the nerve gap. In the nerve guidance channel (NGC) group, polarized piezoelectric PVDF tube containing NGF and collagen gel was sutured in the gap. In control group sciatic nerve was removed (10 mm) without repair. After one, four and eight weeks, the L4-L6 spinal cord segment was removed for histological study using transmission electron microscope. Functional outcome was assessed using the Basso, Bresnahan and Beattie (BBB) locomotor scale at both four and eight weeks after the lesion. RESULTS: Chromatin condensation was seen after 4 weeks in the repair groups. Cell membrane shrinkage and mitochondrial degeneration was observed after 4 and 8 weeks respectively, in the autografted and NGC rats. In the control group, chromatin condensation, cell membrane shrinkage with mitochondrial degeneration and vacuolization of perikaryon was seen after 1, 4 and 8 weeks, respectively. At 56 days, the functional recovery of the epineural rats significantly increased in comparison to the other groups (P< 0.05). CONCLUSION: The epineural suture has more efficacies, and NGC may be used as a proper substitute for autograft in nerve injury.

Repair of peripheral nerve defects using a polyvinylidene fluoride channel containing nerve growth factor and collagen gel in adult rats.

OBJECTIVE: As effectiveness of the autologous graft in the repair of long nerve defects is very limited an effective substitute is needed. This study was conducted to determine the poled polyvinylidene fluoride (PVDF) tube as an alternative to nerve autograft. MATERIALS AND METHODS: The left sciatic nerve was transected in 45 male Wistar rats. The animals were then divided randomly into three groups: in an epineural group the nerve was sutured end to end; in an autograft group a 10 mm piece of sciatic nerve was cut, rotated 180° and sutured in the nerve gap; and in a nerve guidance channel group (NGC), PVDF, tube containing nerve growth factor (NGF) and collagen gel was placed in the gap. In a control (n=15) group the sciatic nerve was exposed but not transected. To determine axonal regeneration, retrograde DiI tracer was injected into the gastrocnemius muscle. One week later, retrograde-labeled neurons were counted in the L4-L6 spinal segments and one way ANOVA analysis was performed to compare groups. Neuronal morphology changes were studied by electron microscopy. RESULTS: Significant statistical decreases in the mean number of labeled motoneurons were observed in all surgical groups compared to the control group; and in the autograft and the NGC groups compared to epinural suture group (p<0.01). No significant difference in the mean number of motoneurons was observed between the autograft and NGC groups. Chromatin condensation, dilated endoplasmic reticulum and large vacuoles were observed in the autograft and NGC groups. CONCLUSION: Regarding the positive effects of PVDF tube containing NGF and Collagen gel on the sciatic nerve regeneration, authors suggest that it may be useful in peripheral nerve repair.