Nerve grafts prevent paraplegic pressure ulcers

We present an optimistic neural solution to the depressing challenge of decubitus pressure ulcers in the paraplegic patient. This is a limited study of two paraplegic men followed for several years. Sural nerve grafts, performed end-to-side, successfully bridged the sciatic nerve to intercostal nerves with surprising benefits for both men.

Stimulation of polygalacturonase production in an immobilized system by Aspergillus sp.: effect of pectin and glucose

The synthesis of polygalacturonases (PG) is known to be influenced by Aspergillus growth conditions, namely, environmental factors and pectin content in the cultivation medium containing a mixed carbon source. Optimal conditions were attained at a temperature of 30 A degrees C and an initial pH of 4.5. PG activity (3.29 and 2.48 U/mL) was determined after a two-day culture of Aspergillus sp. HC1 and Aspergillus sp. CC1, respectively, in a basic medium containing 2% citrus pectin as the sole carbon source. The addition of glucose (2% w/v) to the basic medium led to a 2-fold increase in PG production. However, enzyme synthesis was repressed when a higher concentration of glucose was used in the medium containing the mixed carbon source. Spores from the two fungi were immobilized in a 3% Ca-alginate system and the mechanical strength of the gel beads allowed the use of this process system 6-fold longer (288 h) than the free culture. In the Aspergillus sp. CC1 immobilized system, PG production increased nearly 10-fold in the medium with 2% glucose added (5.95 U/mL) in comparison to the medium without sugar (0.55 U/mL). The results demonstrate that a different response in activity was produced by free and entrapped spore systems. PG production remained approximately constant throughout the six 48 h cycles in the medium containing citrus pectin (2% w/v) as the sole carbon source.

Guanidine Affects Differentially the Twitch Response of Diaphragm, Extensor Digitorum Longus and Soleus Nerve-Muscle Preparations of Mice

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Static balance and function in children with cerebral palsy submitted to neuromuscular block and neuromuscular electrical stimulation: Study protocol for prospective, randomized, controlled trial

Background: The use of botulinum toxin A (BT-A) for the treatment of lower limb spasticity is common in children with cerebral palsy (CP). Following the administration of BT-A, physical therapy plays a fundamental role in potentiating the functionality of the child. The balance deficit found in children with CP is mainly caused by muscle imbalance (spastic agonist and weak antagonist). Neuromuscular electrical stimulation (NMES) is a promising therapeutic modality for muscle strengthening in this population. The aim of the present study is to describe a protocol for a study aimed at analyzing the effects of NMES on dorsiflexors combined with physical therapy on static and functional balance in children with CP submitted to BT-A.Methods/Design: Protocol for a prospective, randomized, controlled trial with a blinded evaluator. Eligible participants will be children with cerebral palsy (Levels I, II and III of the Gross Motor Function Classification System) between five and 12 years of age, with independent gait with or without a gait-assistance device. All participants will receive BT-A in the lower limbs (triceps surae). The children will then be randomly allocated for either treatment with motor physical therapy combined with NMES on the tibialis anterior or motor physical therapy alone. The participants will be evaluated on three occasions: 1) one week prior to the administration of BT-A; 2) one week after the administration of BT-A; and 3) four months after the administration of BT-A (end of intervention). Spasticity will be assessed by the Modified Ashworth Scale and Modified Tardieu Scale. Static balance will be assessed using the Medicapteurs Fusyo pressure platform and functional balance will be assessed using the Berg Balance Scale.Discussion: The aim of this protocol study is to describe the methodology of a randomized, controlled, clinical trial comparing the effect of motor physical therapy combined with NMES on the tibialis anterior muscle or motor physical therapy alone on static and functional balance in children with CP submitted to BT-A in the lower limbs. This study describes the background, hypotheses, methodology of the procedures and measurement of the results.

Clinical significance of supplementary innervation of the lower incisor teeth: a dissection study of the myelohyoid nerve

In view of the relevance of the mylohyoid nerve to clinical difficulties in achieving deep analgesia of the lower incisors, a dissection study was undertaken. Dissections from 29 adult cadavers of both sexes were studied with the aid of a dissecting microscope. The following observations were made: a supplementary branch of the mylohyoid nerve entered the mandible through accessory foramina in the lingual side of the mandibular symphysis in 50% of the cases; it generrally arose from the right side (76.9%) and entered the inferior retromental foramen (84.6%); the mylohyoid nerve branch either ended directly in the incisor teeth and the gingiva or joined the ipsilateral or contralateral incisive nerve. In view of this information concerning the high incidence of possible involvement of the mylohyoid nerve in mandibular sensory innervation, it is advisable to block it whenever intervention in the lower incisors is indicated. Routine mylohyoid injection is recommended after mental nerve block. If the inferior alveolar nerve is chosen for anesthetic purposes, additional mylohyoid injection should be given only if pain persists. The mylohyoid injection should be given at the inferior retromental foramen on the median aspect of the inferior border of the mandible through extraoral approach.

Fine structure of lamellated nerve endings in the gingiva of man and the Cebus apella monkey

Gingival mucosae of man and the adult Cebus apella monkey were fixed for 3 hr in modified Karnovsky fixative containing 2.5% glutaraldehyde, 2% formaldehyde in 0.1 M sodium phosphate buffer (pH=7.4). The specimens were postfixed in 1% osmium tetroxide in 0.1 M sodium phosphate buffer at 4°C for 2 hr, dehydrated in a graded alcohol series and embedded in Epon 812. Thick sections of 1-3 μm and ultrathin sections of 40-80 nm in thickness were cut with glass knives on an LKB ultramicrotome. The thick sections were stained with toluidine blue solution, and the grids were stained with uranyl acetate and lead citrate and examined under a Philips EM-301 electron microscope. Our observations permitted us to conclude that: both gingival mucosae, of man and the Cebus apella monkey, have lamellar nerve endings; these corpuscles are localized in the papillar space of the epithelium and do not contact closely with the basement membrane; the nerve endings are composed of an afferent fiber which subdivides several times and forms irregular flattened or discoidal expansions; the laminae of the lamellar cells are very thin near the terminal axon and are larger and irregular in shape at the peripheral portion of the corpuscle; the terminal axon shows abundant mitochondria, myelin figures, clear vesicles, and multivesicular bodies; between the axoplasm membrane and adjacent cytoplasmic lamina and between the lamellae, small desmosome type junctions are noted; and the cytoplasmic material of the lamellae cells is characterized by the presence of numerous microfilaments, microtubules, mitochondria, rough endoplasmic reticulum, and caveolae.

Effect of cholinergic and adrenergic stimulation of the subfornical organ on water intake

Cholinergic and adrenergic agonists and antagonists were injected directly into the subfornical organ (SFO), via implanted cannulae, and the volume of water ingested was recorded over a period of 1 hour after injection. Application of 2 nmol carbachol caused intense water intake in 100% of the animals (8.78±0.61 ml), with a very short intake latency. When the 2 nmol carbachol dose was preceded by increased doses of atropine, a progressive reduction in water intake was observed, with complete blockage of the thirst-inducing response to carbachol at the 20 nmol dose level with atropine. Followed by several doses of hexamethonium, the water intake caused by application of 2 nmol carbachol was reduced, although the response was not totally blocked. Injection of 80 nmol of nicotine had a significant thirst-inducing inducing effect in 50% of the animals studied (1.06±0.18 ml) and increase in water intake was further reduced by application of increased doses of hexamethonium. Raising the dose levels of noradrenaline into th SFO caused an increase in water intake although to a lesser degree than was observed after carbachol injection. When the 40 nmol dose of noradrenaline was preceded by increased doses of propranolol (5 to 40 nmol), there was a gradual reduction in water intake, with total blockage at the 40 nmol dose. Application of phentolamine in doses of 10 to 80 nmol caused no reduction in water intake after 40 nmol of noradrenaline. Application of isoproterenol at doses from 20 to 160 nmol into the SFO caused a dosedependent increase in water intake which was blocked by previous applications of propranolol. These results support the hypothesis that the water intake caused by chemical stimulation of the SFO is mainly due to muscarinic cholinergic receptors, although the influence of nicotinic receptors or participation of adrenergic mediation should not be ruled out. © 1984.

Natriuresis induced by cholinergic stimulation of the locus coeruleus in the rat

Carbachol injected into the locus coeruleus (LC) induced a dose-dependent natriuresis in the rat. This natriuresis was maintained above control levels during the 120 min of urine sampling. Seizures and arterial blood pressure increase were also observed but they disappeared within 20 min after carbachol injection. Natriuresis was not obtained with either injections of carbachol outside the LC or with hypertonic solutions injected into the LC. Injection of atropine into the LC blocked the natriuresis induced by carbachol. In summary, our data show that carbachol induces natriuresis by an action on muscarinic receptors located in the LC region. © 1990.

Opiate activation suppresses the drinking, pressor and natriuretic responses induced by cholinergic stimulation of the medial septal area

The present study investigates the participation and interaction between cholinergic and opiate receptors of the medial septal area (MSA) in the regulation of Na+, K+ and water excretion, drinking and blood pressure regulation. Male Holtzman rats were implanted with stainless steel cannulae opening into the MSA. Na+, K+ and water excretion, water intake and blood pressure were measured after injection of carbachol (cholinergic agonist), FK-33824 (an opiate agonist) + carbachol or naloxone (an opiate antagonist) + carbachol into MSA. Carbachol (0.5 or 2.0 nmol) induced an increase in Na+ and K+ excretion, water intake and blood pressure and reduced the urinary volume. FK-33824 reduced the urinary volume and Na+ and K+ excretion. Previous injection of FK-33824 (100 ng) into the MSA blocked the increases in Na+ and K+ excretion, water intake and blood pressure induced by carbachol. Naloxone (10 μg) produced no changes in the effect of 2.0 nmol carbachol, but potentiated the natriuretic effect induced by 0.5 nmol dose of carbachol. These data show an inhibitory effect of opiate receptors on the changes in cardiovascular, fluid and electrolyte balance induced by cholinergic stimulation of the MSA in rats. © 1992.

Latero-terminal neurorrhaphy without removal of the epineural sheath. Experimental study in rats.

Termino-lateral neurorrhaphies have been used up to the beginning of this century. After this period, they have no longer been reported. We tested the efficacy of a new type of latero-terminal neurorrhaphy and evaluated the role of the epineural sheath. A group of 10 rats had the fibular nerve sectioned and the distal ending was sutured to the lateral face of the tibial nerve without removing the epineurium. All experiments were made on the right side, the left one remaining untouched in half of the animals of each group. The other half were denervated by sectioning and inverting the endings of the fibular nerves. In this way, tibial cranial muscles were either normal or denervated in the left side and reinnervated through latero-terminal neurorrhaphy in the right side. After 7.7 months, the animals were subjected to electrophysiological tests, sacrificed, and the nerves and muscles were taken for histological exams. A response of the tibial cranial muscle was obtained in 75% of the animals. The distal ending of the fibular nerve showed an average of 498 nerve fibers. The average areas of the reinnervated tibial cranial muscles were (mu 2):841.30 for M2n and 1798.33 for M2d. We concluded that the termino-lateral neurorrhaphy was functional, conducting electrical stimuli and allowing the passage of axons from the lateral surface of a healthy nerve, to reconstitute the distal segment of a sectioned nerve. The presence of the epineurium was no impediment to axonal regeneration or to the passage of electrical stimuli.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of nicotinic stimulation of the amygdaloid complex on water and sodium chloride intake

We studied the nicotine stimulation of the amygdaloid complex (AMG) on sodium and water intake in satiated and water-deprived rats. Nicotine produced no change in sodium or water intake in satiated animals when injected directly into the AMG. In water-deprived animals, nicotine injected into the AMG (basolateral nuclei) only blocked sodium chloride intake. We have previously demontrated that carbachol inhibits water and sodium intake in both satiated and water-deprived animals injected into the AMG. Injection of hexamethonium into the AMG totally blocked water intake in satiated and water-deprived animals. Hexamethonium injected into the AMG prior to nicotine produced no change in sodium intake. Thus, the present data suggest that sodium and water intake are mediated by a specific population of cholinoceptive neurons in the amygdaloid complex.

Experimental surgery of the facial nerve. Assessment of the intraperitoneal use of exogenous gangliosides

Compression and section of the facial nerve were performed in 48 rats in order to study the anatomopathological alterations occurring after daily intraperitoneal injections of 100 mg of exogenous gangliosides (Sinaxial®) for 45, 90, 180 days. In groups submitted to nerve compression, the histopathological changes were discrete and in the 180-day subgroups the nerve was practically normal. In animals submitted to section and neurorrhaphy there was formation of an amputation neuroma, a granuloma around the suture, axonal unstructuration and inter and perineural fibrosis. No significant differences were observed between the groups submitted or not to injection of exogenous gangliosides, indicating that the major factors involved in the quality of nerve regeneration were the technique and the formation of fibrosis and of an amputation neuroma.

On a dual role for clonidine stimulation of the ventromedial nucleus of the hypothalamus in sodium and potassium renal excretions of rats

The effects of clonidine on sodium and potassium excretions were examined after previous administration of prazosin (an α 1-adrenergic receptor antagonist) and yohimbine (an α 2-adrenergic receptor antagonist) into the ventromedial nucleus of the hypothalamus of conscious rats. Clonidine injected into the ventromedial nucleus of the hypothalamus induced inhibitory and facilitatory effects on the urinary sodium and potassium excretions. The results suggest that facilitatory effects of clonidine on natriuresis and kaliuresis are mediated through activation of α 1-adrenoceptors and that inhibitory effects require α(2A)-adrenoceptors.

Effect of adrenergic stimulation of the amygdaloid complex on water intake

The effect of noradrenaline, isoproterenol, phentolamine and propranolol, injected into the basolateral nuclei of the amygdala on water intake, was investigated in male Holtzman rats. The injection of noradrenaline (40 nmol) into the amygdaloid complex (AC) of satiated rats produced no change in water intake (0.05 ± 0.03 ml/1 hour). The injection of isoproterenol (40 nmol) produced an increase in water intake in sedated rats (1.93 ± 0.23 ml/1 hour). Noradrenaline injected into the AC produced a decrease in water intake in deprived rats (0.40 ± 0.19 ml/1 hour). The injection of isoproterenol into the AC of deprived rats produced no change in water intake in comparison with control (11.65 ± 1.02 and 10.92 ± 0.88 ml/1 hour, respectively). When compared with control values, phentolamine injected prior to noradrenaline blocked the inhibitory effect of noradrenaline on water intake in deprived rats (10.40 ± 1.31 ml/1 hour). Propranolol blocked the effect of isoproterenol in satiated rats (0.85 ± 0.49 ml/1 hour) and also blocked the water intake induced by deprivation (0.53 ± 0.38 ml/1 hour). In satiated and deprived animals the injection of phentolamine before hexamethonium blocked the inhibitory effect of hexamethonium on water intake. In satiated animals, when hexamethonium was injected alone, water intake was 0.39 ± 0.25 ml/1 hour and when hexamethonium was injected with phentolamine, water intake was 1.04 ± 0.3 ml/1 hour. In deprived animals, hexamethonium alone blocked water intake (0.40 ± 0.17 ml/1 hour) and when injected with phentolamine it elicited an intake of 9.7 ± 1.8 ml/1 hour. these results clearly demonstrate the participation of catecholaminergic receptors of the AC in the regulation of water intake.