Limb Muscle Reinnervation with the Nerve-Muscle-Endplate Grafting Technique: An Anatomical Feasibility Study

Background. Peroneal nerve injuries results in tibialis anterior (TA) muscle paralysis. TA paralysis could cause “foot drop,” a disabling condition that can make walking difficult. As current treatment methods result in poor functional recovery, novel treatment approaches need to be studied. The aim of this study was to explore anatomical feasibility of limb reinnervation with our recently developed nerve-muscle-endplate grafting (NMEG) in the native motor zone (NMZ). Methods. As the NMEG-NMZ technique involves in nerves and motor endplates (MEPs), the nerve supply patterns and locations of the MEP bands within the gastrocnemius (GM) and TA muscles of rats were investigated using Sihler’s stain and whole-mount acetylcholinesterase (AChE) staining, respectively. Five adult rats underwent TA nerve transaction. The denervated TA was reinnervated by transferring an NMEG pedicle from the ipsilateral lateral GM. At the end of a 3-month recovery period, maximal muscle force was measured to document functional recovery. Results. The results showed that the TA was innervated by the deep peroneal nerve. A single MEP band was located obliquely in the middle of the TA. The GM was composed of two neuromuscular compartments, lateral (GM-l) and medial (GM-m), each of which was innervated by a separate nerve branch derived from the tibial nerve and had a vertically positioned MEP band. The locations of MEP bands in the GM and TA muscles and nerve supply patterns demonstrated that an NMEG pedicle can be harvested from the GM-l and implanted into the NMZ within the TA muscle. The NMEG-NMZ pilot study showed that this technique resulted in optimal muscle force recovery. Conclusion. NMEG-NMZ surgery is feasible for limb reinnervation. Specifically, the denervated TA caused by peroneal nerve injuries can be reinnervated with a NMEG from the GM-l.

Muscle-Nerve-Nerve Grafting Improves Facial Reanimation in Rats Following Facial Nerve Injury

Nerve injury resulting in muscle paralysis from trauma or surgery is a major medical problem. Repair of such injuries with existing nerve grafting and reconstructive techniques often results in less than optimal outcomes. After previously demonstrating significant return of function using muscle-nerve-muscle (MNM) grafting in a rat facial nerve model, this study compares a variant of the technique, muscle-nerve-nerve (MNN) neurotization to MNM and interposition (IP) nerve grafting. Thirty male rats were randomized into four groups (1) control with no intervention, (2) repair with IP grafts, (3) MNM grafts and (4) MNN grafts. All groups had the buccal and marginal mandibular branches of the right facial nerve resected. Return of vibrissae movement, orientation, and snout symmetry was measured over 16 weeks. Functional recovery and muscle atrophy were assessed and quantified. All interventions resulted in significant improvement in vibrissae movement and orientation as compared to the control group (p < 0.05). The MNM and MNN groups had significantly less time to forward vibrissae movement as compared to controls (p < 0.05), and a large number of animals in the MNN group had coordinated vibrissae movement at 16 weeks. MNN and IP grafts retained significantly more muscle mass as compared to control (p < 0.05). Thus, MNN grafting is a promising adjuvant or alternative technique for reanimation for patients with unilateral peripheral nerve injury who are not candidates for primary neurorrhaphy.

CONTENT ANALYSIS OF SOME DOCTORAL THESIS STUDIES CARRIED OUT IN TURKEY ON THE BRANCH OF TAEKWONDO IN THE FIELD OF SPORTS SCIENCES

<p>Taekwondo is an old martial art with a Korean origin that is performed with hands and feet, where several combined techniques are used together, and nerve-muscle use levels are high (Mark, 1984; Kim et al., 2011). The history of taekwondo may be traced back to centuries ago. Initially, this branch used to be taught for the person to defend themselves. Afterwards, throughout the centuries, it has been spread around the world as an artistic form. In addition to having an artistic form, the branch of taekwondo also requires high competitive strength. Taekwondo is a competitive sport that requires the displacement of the body parts of the opponent. As words, ‘tae’ means foot strike, ‘kwon’ means hand strike, and ‘do’ means philosophy (Kazemi et al., 2006). Taekwondo competitions are divided into two categories as sparring and poomsae. Sparring is performed against an opponent, while poomsae (imaginary sparring) is a branch where a single person performs. Taekwondo that is known as a demonstration sport showed itself for the first time in the 1988 Seoul and 1992 Barcelona Olympics. Its inclusion in official competitions occurred in the 2000 Sydney Olympic Games (Kazemi et al., 2004; Gupta, 2011). Taekwondo as an Olympic sport is a branch performed by 75-120 million individuals in more than 140 countries (Razi, 2016). Innovations made in equipment in time, changes in rules, safety measures, organization of competitions, and its prominent media- and education-related aspects have increasingly raised the interest in this branch and helped it gain its popularity today. With the increase in the popularity of the branch and the prominence it has gained in the Olympics, World Taekwondo has recently made some changes in the rules. Some changes may be listed as changes in the scoring system (increase in the point score of techniques applied on the head region), smaller game dimensions, enaction of the 10-sec rule and changes in penalty points (Moenig, 2015). Competitions are held in the form of 3 rounds of 1.5 minutes each for the Juniors and Teens categories and 3 rounds of 2 minutes each for the Youths and Adults categories, with 1 minute of rest between the rounds (Birrer, 1996; Toskovic et al. 2004; Heller ve ark., 1998). Competitions consist of various techniques applied on the head and torso regions. These techniques may be applied in the form of attack, counterattack and combined techniques. Athletes are scored based on the region on which they apply the techniques and the degree of difficulty. For athletes to receive points, they need to have multiple physical qualities. For competitive performance, taekwondo requires various factors including physical (Heller ve ark., 1998; Gao, 2001; Melhim, 2001; Ball et al.,2011; Estevan et al., 2011), psychological (de Prado, 2012), technical (Bridge et al., 2011; Cular et al., 2011) and tactical (Falcó et al., 2009; González et al., 2011) factors. This is why taekwondo training has been structured in a way to target these specific performance mediators (Heller et al., 1998; Gao, 2001). From this perspective, the purpose of taekwondo training is to prepare athletes in terms of both their physical activities and meeting of the physiological demands of competition (Marković et al., 2005; Pieter, 1991; Casoline et al., 2012). As strikes are important in taekwondo, athletes need to have explosive leg strength, aerobic resilience, balance and flexibility (Heller et al., 1998; Marković et al., 2005). Taekwondo athletes must have the capacity to rapidly produce muscle strength through kicks, because 80% of taekwondo skills are related to kicking (Shirley, 1992). Although these characteristics are not the only determinants of performance, they are among helpful pieces of information for trainers. There are studies in the literature on the physical and physiological characteristics of athletes. Nevertheless, it is important to increase the number of these studies and select the suitable training method for this group of athletes.</p><p> </p><p><strong> Article visualizations:</strong></p><p><img src="/-counters-/edu_01/0985/a.php" alt="Hit counter" /></p>

Olivopontocerebellar degeneration associated with 3-hydroxy-3-methylglutaric aciduria in a domestic shorthair cat

Case summary A rescue charity-owned 6-month-old neutered female domestic shorthair cat was presented with progressive tetraparesis, increased extensor muscle tone and signs of spinocerebellar ataxia, including hypermetria. The cat’s male sibling, with similar progressive neurological signs, had been euthanased 2 months previously. An inherited metabolic disorder was suspected. Urine for determination of organic acid concentration was obtained and the cat was prescribed carnitine and taurine supplementation. The cat was euthanased 3 months later following progressive neurological signs, including ataxia, tetraparesis, tendency to fall, bilateral absent menace response and intention tremor. A selective post-mortem examination was obtained, taking samples from the brain, cervical spinal cord, tibial branch of the sciatic nerve, muscle, liver and kidneys. Organic acid analysis results received after euthanasia revealed a marked elevation of 3-hydroxy-3-methylglutaric acid (45 mmol/mol creatine [normal range 0–2]) and isovalerylglycine (27 mmol/mol creatinine [normal range 0–2]). 3-Hydroxy-3-methylglutaric acid was deemed clinically relevant as it is a metabolite of 3-hydroxy-3-methylglutaryl-CoA lyase, the enzyme involved in the final step of leucine degradation. Post-mortem examination revealed diffuse, chronic-active, severe olivoponto-(spino)-cerebellar degeneration. Relevance and novel information This is the first report of 3-hydroxy-3-methylglutaric aciduria in the veterinary literature and the first description of the neuropathology of this disorder in any species. 3-Hydroxy-3-methylglutaric aciduria in humans occurs rarely and is due to a deficiency in 3-hydroxy-3-methylglutaryl-coenzyme A lyase.

ANATOMY OF ANSA CERVICALIS AND ITS VARIATIONS

BACKGROUND: The ansa cervicalis is usually used to re-innervate the larynx following recurrent laryngeal nerve paralysis in thyroid cancer, oesophageal cancer following lymphadenectomy. Variations have previously been reported on the formation and branching pattern of the ansa cervicalis loop. Objectives: The present study aimed to record anatomical variations of the formation of loop and branches of ansa cervicalis. The study was done in Anatomy depa METHODS: rtment, Assam Medical College, Dibrugarh, Assam. 30 numbers (15 cadaver x 2) of ansa cervicalis were studied. A thorough morphological study was done and the results were recorded. RESULTS: Normal anatomy & variations, if any, of the ansa cervicalis were noted and discussed with previous studies. CONCLUSION: Surgical procedures such as thyroplasty, arytenoid adduction, nerve-muscle pedicle implantation had been reported to cause iatrogenic injuries to the ansa cervicalis. Knowledge of the arrangement of loops and branches of the ansa cervicalis will be helpful for planning a safe surgery in the neck region.

Effects Of Doxycycline On Mice Neuromuscular Junction, In Situ

Background: The antibacterial mechanism of doxycycline is known, but on the nerve-muscle apparatus is yet unclear. Objective: To combine molecular targets of the neuromuscular machinery using the neuronal blocker effect doxycycline, a semisynthetic second-generation tetracycline derivative, on mice neuromuscular preparations, in situ. Methods: Doxycycline was assessed at the neurotransmission; presynaptic; synaptic cleft; and postsynaptic, including the muscle fiber, using the traditional myographic technique. Preliminarily, doxycycline showed an "all or nothing" effect, being "all" obtained with 4 µM and "nothing", with 1-3 µM. The rationale of this study was to apply known pharmacological tools against the blocker effect of 4 µM doxycycline such as F55-6 (Casearia sylvestris), CaCl2 (or Ca2+), atropine, neostigmine, polyethylene glycol (PEG 400), and d-Tubocurarine. The evaluation of cholinesterase enzyme activity, the diaphragm muscle histology, and protocols on the neuromuscular preparation submitted to indirect or direct stimuli were complementary. Results: Doxycycline does not affect cholinesterase activity nor cause damage to skeletal muscle diaphragm; acts on ryanodine receptor, sarcolemmal membrane, and on neuronal sodium channel with a postjunctional consequence due to the decreased availability of muscle nicotinic acetylcholine receptors. Conclusions: In conclusion, using the blocker effect we showed that doxycycline acts on multiple targets, among them, is antagonized by F55-6, a neuronal Na+-channel agonist and Ca2+, but not by neostigmine.

Effect of Indian Polyvalent Antivenom in the Prevention and Reversal of Local Myotoxicity Induced by Common Cobra (Naja naja) Venom from Sri Lanka In Vitro

Bites by many Asiatic and African cobras (Genus: Naja) cause severe local dermonecrosis and myonecrosis, resulting in permanent disabilities. We studied the time scale in which two Indian polyvalent antivenoms, VINS and Bharat, remain capable of preventing or reversing in vitro myotoxicity induced by common cobra (Naja naja) venom from Sri Lanka using the chick biventer cervicis nerve-muscle preparation. VINS fully prevented while Bharat partially prevented (both in manufacturer recommended concentrations) the myotoxicity induced by Naja naja venom (10 µg/mL) when added to the organ baths before the venom. However, both antivenoms were unable to reverse the myotoxicity when added to organ baths 5 and 20 min post-venom. In contrast, physical removal of the venom from the organ baths by washing the preparation 5 and 20 min after the venom resulted in full and partial prevention of the myotoxicity, respectively, indicating the lag period for irreversible cellular injury. This suggests that, although the antivenoms contain antibodies against cytotoxins of the Sri Lankan Naja naja venom, they are either unable to reach the target sites as efficiently as the cytotoxins, unable to bind efficiently with the toxins at the target sites, or the binding with the toxins simply fails to prevent the toxin-target interactions.

A comparison of the antidotal effects of three oximes against an organophosphate on chick skeletal muscle

Background: One of the most toxic effects of organophosphorus poisoning (OP) is the paralysis of skeletal muscles. The oximes are a group of available antidotes. This study investigated the effects of different concentrations of paraoxon on the function of skeletal muscle and reversal or prevention of these effects by three different oximes (i.e., pralidoxime, obidoxime, and HI-6). Materials and Methods: This study was conducted based on the chicken biventer cervices (CBC) nerve-muscle preparation and the use of twitch tension recording technique. The twitches of the CBC were evoked by stimulating the motor nerve at 0.1 Hz with pulses of 0.2 msec duration and a voltage greater than that required to produce the maximum response. Moreover, twitches and contractures were recorded isotonically using Grass Biosystems. Results: Paraoxon at 0.1 µM induced a significant increase (more than 100%) in the twitch amplitude, while higher concentrations (0.3 and 1µM) induced partial or total contracture. Therefore, paraoxon at a concentration of 0.1 µ M was used to examine the capability of oximes to prevent or reverse its effects. Pralidoxime, obidoxime, and HI-6 dose-dependently prevented (when it was used as pre-treatment, 20 min before or at the same time of administration of the toxin) and reversed (when it was used as post-treatment, 20 min after the administration of the toxin) the effect of paraoxon. Conclusion: In conclusion, these results revealed that oximes were very useful in the prevention and reversal of the OP toxic effects on the skeletal muscle. Moreover, it was suggested that oximes were more effective when used as pre-treatment. Pralidoxime was more potent than obidoxime and HI-6. The HI-6, which is a newer oxime, was unexpectedly less effective than the other two.

Regulatory Function of Sympathetic Innervation on the Endo/Lysosomal Trafficking of Acetylcholine Receptor

Recent studies have demonstrated that neuromuscular junctions are co-innervated by sympathetic neurons. This co-innervation has been shown to be crucial for neuromuscular junction morphology and functional maintenance. To improve our understanding of how sympathetic innervation affects nerve–muscle synapse homeostasis, we here used in vivo imaging, proteomic, biochemical, and microscopic approaches to compare normal and sympathectomized mouse hindlimb muscles. Live confocal microscopy revealed reduced fiber diameters, enhanced acetylcholine receptor turnover, and increased amounts of endo/lysosomal acetylcholine-receptor-bearing vesicles. Proteomics analysis of sympathectomized skeletal muscles showed that besides massive changes in mitochondrial, sarcomeric, and ribosomal proteins, the relative abundance of vesicular trafficking markers was affected by sympathectomy. Immunofluorescence and Western blot approaches corroborated these findings and, in addition, suggested local upregulation and enrichment of endo/lysosomal progression and autophagy markers, Rab 7 and p62, at the sarcomeric regions of muscle fibers and neuromuscular junctions. In summary, these data give novel insights into the relevance of sympathetic innervation for the homeostasis of muscle and neuromuscular junctions. They are consistent with an upregulation of endocytic and autophagic trafficking at the whole muscle level and at the neuromuscular junction.

Midline and Mediolateral Episiotomy: Risk Assessment Based on Clinical Anatomy

Episiotomy is the surgical incision of the vaginal orifice and perineum to ease the passage of an infant’s head while crowning during vaginal delivery. Although episiotomy remains one of the most frequently performed surgeries around the world, short- and long-term complications from the procedure are not uncommon. We performed midline and mediolateral episiotomies with the aim of correlating commonly diagnosed postepisiotomy complications with risk of injury to perineal neuromuscular and erectile structures. We performed 61 incisions on 47 female cadavers and dissected around the incision site. Dissections revealed that midline incisions did not bisect any major neuromuscular structures, although they did increase the risk of direct and indirect injury to the subcutaneous portion of the external anal sphincter. Mediolateral incisions posed greater risk of iatrogenic injury to ipsilateral nerve, muscle, erectile, and gland tissues. Clinician discretion is advised when weighing the potential risks to maternal perineal anatomy during vaginal delivery when episiotomy is indicated. If episiotomy is warranted, an understanding of perineal anatomy may benefit diagnosis of postsurgical complications.