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Showing 8 results for Torkaman

Seyed Mohammad Firoozabadi, Giti Torkaman, Fatemeh Ebrahimi,
Volume 6, Issue 1 (Spring and Summer 2002)

Although low-threshold transcutaneous electrical nerve stimulation (TENS) is a modality used for control of pain, but its effect in the control of spasticity and change of excitability of a motor neuron is controversial. Therefore, this study was conducted to evaluate the effects of 15-min tripolar TENS of vertebral column and bipolar TENS of common peroneal nerve (300 µs width, 50 Hz) on synaptic activities of spinal cord. For this purpose, soleus H-reflex, Mh wave (M wave on the H-reflex signal) and M wave parameters were studied. Twelve healthy and non-athletic female volunteers were tested in two groups. First group received vertebral column stimulation and second group received peripheral stimulation in 4 separate experimental sessions (two control and two test sessions). In the first group, tripolar TENS (cathode on T 11, one anode 3 cm above and the other 7 cm below the cathode) was applied. In the second group, bipolar TENS (cathode on common peroneal nerve at the level of fibular head and anode 3 cm below the cathode) was used. Then, the acquired data were analyzed statistically. The results showed that peak to peak amplitude (PP), area under the curve and average rectified value (ARV) of H-reflex in the first stimulation group decreases (p<0.05), but in the second group, there is no significant changes. In addition, these parameters increased for Mh wave in the first group, but in the second group, there were no significant changes. It is suggested that tripolar TENS of vertebral column has augmented activity of the fast motor units. In this respect, it is possible that Renshaw cells are more activated and suppressed the activity of the slow motor units. These effects tended to increase the sensitivity of soleus motor end plate and decrease H-reflex amplitude. It can be concluded that tripolar TENS of vertebral column (depending on the site and method of stimulation) appears to be effective in synaptic activities of the spinal cord, especially the fast motor units and Renshaw cells, while bipolar TENS of common peroneal nerve does not produce such effect.
Arezoo Navid, Giti Torkamani, Seyed Mohammad Firoozabadi,
Volume 7, Issue 2 (Fall and Winter 2003)

Electrical stimulation of neuromuscular system has been used in a variety of research and therapeutic applications. Although tri-polar transcutaneous electrical stimulation (TENS) is commonly used to change motoneuron excitabi1ity, but the effect of TENS on synaptic activities through dorsal column stimulation or cutaneous pathways is unknown. So, the aim of this research study was to determine the role of cutaneous receptors in conductance of TENS. For this purpose, 10 healthy non-athlete volunteers were tested in three separated sessions, i.e. control 1 (placebo spray and silent TENS), control 2 {lidocaine spray and silent TENS), and experimental (lidocaine spray and TENS) groups. Tri-polar TENS was used on vertebral column (cathode on Tll, one anode 3cm above and another 6cm below the cathode). For evaluation of motoneuron activity, soleus H-reflex and Mh wave recruitment curve were evaluated. We sprayed water (Placebo) and 10% lidocaine on the vertebral column skin under the electrodes for 20 sec. In the experimental session, tripolar TENS on desensitized skin of the vertebral column was applied. TENS was applied for 15 minutes with a frequency of 100 Hz and a pulse width of 300 µs. The results showed that Hmax evocation intensity decreases after application of placebo and lidocaine spray (p<0.05). The positive slope of H-reflex recruitment curve also increased after application of placebo and lidocaine spray (p<0.05). Based on the above results, we suggest a theory to explain the change of synaptic activities of spinal cord as foIlows: Low-threshold cutaneous receptors diminish the pre-synaptic inhibition of la afferent fibers and application of TENS on the desensitized skin increases fit L5 slope and decreases fit L3 slope of H-reflex recruitment curve. In this study, since only low-threshold cutaneous receptors were inhibited, therefore, the role of cutaneous receptors in conductance of TENS could not be ignored.
Voya Ravanbod, Giti Torkaman, Mohammad Reza Baghaee Pour, Nadali,
Volume 7, Issue 2 (Fall and Winter 2003)

Hemophilia is an X chromosome-linked inherited bleeding disorder. Frequent intra- articular and intra-muscular haemorrhage in severe haemophiliacs can cause significant disability. In order to resolve a simple bleeding in a 20-kilogram child, some 500 IV of factor VIII is usually required. The cost of this replacement therapy is enormous, especially for less wealthy countries. Vigorous exercise in normal individuals has been known to increase levels of F. VIII:C and vWF:Ag transiently through β-adrenergic stimulation. The goal of this research study was to investigate the effect of ergometric exercise on F. VIII activity in patients with mild and moderate hemophilia-A. Research studies on this phenomenon have not been reported since 1984. Since the previous studies have mainly been carried out on either healthy individuals or patients with cardiac functional abnormalities, it appears appropriate to further characterize the effect of exercise on the coagulation parameters in patients suffering from bleeding disorders. For this purpose, 10 hemophiliacs (a mean age of 24 years) were exercised on a bicycle ergometer in accordance with accepted protocols for a period of 23 to 46 minutes. We deliberately limited the periods of activity because of the low exercise tolerance of these patients. Venous blood samples were drawn before and at 8 and 45 minutes after the exercise. The results showed that the increase in the activity of F .V VIII:C following exercise was very significant among mildly-affected patients, and the reduction in a PTT at 45 minutes after the exercise, the increase in vWF activity 8 minutes after the exercise, and the rise in vWF:Ag in both stages were all significant. It is concluded that ergometric exercise induces a significant increase in F-V VIII activity in both mild and moderate hemophiliacs. Establishing a suitable exercise program in patients with hemophilia A not only improves the status of their musculo-skeletal system, but also transiently increases the activity of F-V VIII activity. Prophylaxis in severe hemophiliacs could be achieved by means of replacement therapy. Among mildly- or moderately-affected patients, exercise may serve the same purpose and effectively reduce the need for replacement therapy.
Zahra Sadat Rezaeian, Giti Torkaman, Fatemeh Nad-Ali, Roya Ravanbod, Mostafa Nejatian, Babak Gosheh, Mohammad Ali Broumand,
Volume 10, Issue 1 (Spring 2006)

Introduction: Effects of exercise on different body systems, especially cardiovascular and musculoskeletal systems are evidenced. There is a dynamic homeostatic balance between coagulation and fibrinolysis in normal circulation. Effect of exercise and training on this homeostatic balance has been studied extensively but there are a few studies with regards to analysis of the effects of training programs on coagulation factors. Therefore, we studied the effect of 8 weeks aerobic training program on coagulation factors in healthy young men. Methods: Subjects were 16 young sedentary men without any history of cardiac, coagulation or respiratory problems in their first-degree family and their cardiovascular health was confirmed by a cardiac specialist. We randomly selected 10 of them as test group who participated in a submaximal training program on cycle ergometer 3 times a week for 8 weeks. Each training session consisted of 1 minute warm up, 15 minute aerobic exercise, 8 minute active recovery and 45 minute passive recovery. The remaining individuals were controls and restrained from exercise in this period. Before and after training period, response of coagulation system to a submaximal exercise on cycle ergometer was studied by a standardized Ergometery test. Results: Basic value of coagulation variables were the same in both groups before and after training period. After 8 weeks, there was no significant change in anthropometric variables in both groups and so the change in blood variables was independent to physical characteristics of individuals. After 8 weeks of aerobic training, FVIII:c, FIX:c, Fbg and vwF:ac increased in response to exercise that was statistically significant only in Tr group. There was a significant decrease in vwF:ag, aPTT, FVII in this group. We conclude that 8 weeks aerobic training enhances the response of FVIII:c, FIX:c, FVII:c, vwF:ac, Fbg and aPTT to exercise but has no effect on the response of vwF:ag and PT. Conclusion: It seems that the recommended aerobic exercise training protocol will enhance the response of coagulation factors to one session of Ergometric exercise in healthy young men. Due to the importance of blood homeostasis and the effects of coagulation and fibrinolysis imbalance, any type of physical activity especially any exercise program should be analyzed carefully for its effect on haemostatic balance.
Hossein Salehi, Giti Torkaman, Seyed Mohammad Firoozabadi,
Volume 10, Issue 2 (Summer 2006)

Introduction : There are different applications for cooling in rehabilitation and there is also a controversy in results of applying ice on limb and its effects on motorneurons excitability. Methods : This study was done to determine the effect of applying controlled cooling (rubbing cold ointment with 3°C temperature) on the spinal skin (around T place of S root nerve) on the excitability of soleus 11, 11 motorneurons in ten healthy, non-athletic men. Each volunteer was tested in two [control (vazeline ointment with - environment temperature) and examination (cold vazeline)] separate sessions. We used soleus H-reflex and M h wave recruitment curve parameters for evaluation. Stimulation current was a square pulse with 700 microsecond duration and 0.2 Hz frequency. H-reflex was recorded with 9 different amplitudes. Results: Fit L slope, fit L slope and peak to peak amplitude of H-reflex decreased immediately and 30 3 5 minutes after the application of cold ointment. Conclusion: Cold by stimulating the thermoreceptors and reducing the firing rate of surface mechanoreceptors can decrease the excitability of motoneurons and this effect may be long lasting.
Leila Simorgh, Giti Torkaman, Seyyed Mohammad Firoozabadi,
Volume 10, Issue 4 (Winter 2007)

Introduction: Effect of tripolar TENS of vertebral column on slow and fast motoneurons (MNs) activity of soleus muscle was previously investigated. In this study for better differentiation of the behavior of slow and fast MNs, we exploited H-reflex recovery curve recording in two muscles of soleus and lateral gastrocnemius, respectively as the representatives of slow and fast muscles. Methods: 10 healthy non-athlete women aged 22.7±2.21 years participated in two (control and test) sessions. H-reflex recovery curve of soleus (slow) and gastrocnemius (fast) muscles were recorded before and 15 minutes after applying tripolar TENS (TENS frequency= 100 Hz and pulse width= 300 μs) on vertebral column. For recording the curve, rectangular paired stimuli were applied on tibial nerve (ISI= 40-520, frequency= 0.2 Hz, pulse width= 600 μs). Results: Our findings showed that maximum H-reflex recovery in gastrocnemius muscle appeared in shorter ISIs (240 ms), while in soleus muscle it appeared in longer ISIs (400 ms). H-reflex recovery curve amplitude slightly decreased after applying tripolar TENS. The comparison of H-reflex recovery curve of both soleus and gastrocnemius muscles either in control or test session did not show any significant difference (P>0.05). Conclusion: It is suggested that tripolar TENS excites not only the skin but also Ia and Ib afferents in the dorsal column. Synaptic interactions of these afferents in spinal cord cause the inhibition of type I MNs and facilitation of type II MNs.
Mehrdad Habibi, Giti Torkaman, Babak Goosheh, Mehdi Hedayati,
Volume 13, Issue 1 (Spring 2009)

Blood hypercoagulability or thrombogenicity can be one of the main causes of the cardiovascular diseases in young population without traditional pathologic risk factors such as diabetes mellitus, hypertension or hyperlipidemia. The effect of aerobic exercise on coagulation and fibrinolysis has been studied extensively Regarding to the effectivness of resistance exercises to increase functional ability of men, the purpose of this study was to examine the effects of the combined aerobic-resistance and aerobic exercise on the coagulation activity of healthy young men. 30 young healthy sedentary men (20±5 years old) randomly divided in 3 groups: 10 in the combined, 10 in the aerobic and 10 in nontraining matched control groups The training groups subjects were engaged in a program included, ten session, three times per week, with submaximal intensity and 24 min for every session. The combined group had 12 min resistance exercise, followed by a 12 min aerobic exercise on cycle ergometer although aerobic group had only 24 min aerobic exercise on cycle ergometer. The results revealed that PT decreased and PTT increased in training groups. Fibrinogen decreased significantly in both training groups. It was concluded that both submaximal aerobic-resistance and aerobic exercises, decrease coagulation system activity in young healthy sedentary men.
Alireza Sarmadi, Seyyed Mohammad Firoozabadi, Giti Torkaman, Yaghoub Fathollahi,
Volume 13, Issue 2 (Summer 2009)

Abstract: To assess the effect of penetration depth of the surface tripolar electrical stimulation, Tripolar TENS was applied with different intensities (equal to sensory threshold (ST), 1.25 ST, 1.5 ST) on vertebral column of twenty healthy and three hemiplegic subjects. The cathode of TENS was laid on the T11 vertebra and anodes were put 3cm apart from cathode, longitudinally and in the anode-cathode-anode arrangement. Before, after and 10 min after TENS the recruitment curve of soleus and gastrocnemius H-reflex and M wave were recorded. Experiments were done in four separate sessions. One of them was control session and the TENS apparatus was off in it. In each of the test sessions, TENS was applied with one of the intensities. The results showed that the 1.5 ST TENS have a complex facilitatory-inhibitory effect on recruitment curve of soleus H-reflex in the way that slow motoneurons were inhibited and fast motoneurons were facilitated. So the positive slope of curve was increased and the intensity needed to evoke Hmax was decreased. Amplitude of Hmax and threshold of the curve were slightly decreased. Gastrocnemius was facilitated after 1.5 ST TENS. The threshold of the H-reflex curve and needed intensity to evoke Hmax were decreased, while peak to peak amplitude of Hmax was increased. After ST TENS, soleus was facilitated and gastrocnemius had little change. It seems that 1.5 ST TENS facilitate Ia, Ib, fast motoneurons and renshaw cells via stimulating the dorsal column of the cord and renshaw inhibit slow motoneurons, so a complex of facilitation and inhibition appears in soleus motoneurons. In the case of gastrocnemius which the renshaw cells had not strong effect, H-reflex curve was facilitated. In ST TENS which only the skin afferents were stimulated the renshaw cells were inhibited by skin afferents and H-reflex was facilitated, But because the gastrocnemius motoneurons are slightly under control of renshaw and skin afferents synapses with motoneurons are not engaged in reflex loop, facilitation of skin afferents synapses after TENS application had no effect on the H-reflex parameters of gastrocnemius.

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