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AIMS: Since sleep bruxism (SB) is characterized by grinding and clenching of the teeth during sleep and could be an exaggerated manifestation of normal spontaneous rhythmic masticatory muscle activity, the aim of this study was to obtain a neurophysiological assessment of the excitability of the central jaw motor pathways in patients with signs and symptoms suggestive of SB. METHODS: A total of 30 subjects diagnosed with SB on the basis of self-report of tooth grinding were studied using the 'recovery cycle' of the masseter inhibitory reflex (MIR) elicited by electric and magnetic stimulation of the mental nerves and by recording the motor potentials evoked in masseter muscles by transcranial magnetic stimulation. Tests were done during daytime, when the subjects were awake. The data obtained were compared with data from a population of normal subjects. RESULTS: In the putative SB patients and in normal subjects, the MIRs evoked by single electric and magnetic stimuli were similar. With paired stimuli, the degree of suppression of the late silent period was significantly lower (P < .01) in the patients compared to normal subjects, particularly for magnetic stimuli, at various interstimulus intervals. No significant differences were found between the 2 groups of subjects in the masseter motor potentials evoked by transcranial magnetic stimulation. CONCLUSION: Although the data were only obtained during wakefulness in patients self-reporting signs and symptoms suggestive of SB, the findings suggest that an abnormal excitability of the central jaw motor pathways may be present in SB subjects. This increased excitability could derive from an impaired modulation of brainstem inhibitory circuits and not from altered cortical mechanisms. These results support the view that bruxism is mainly centrally mediated and that it involves subcortical structures. The study also indicates that use of the MIR elicited by the double-shock technique could be valuable in the evaluation of bruxism. [ABSTRACT FROM AUTHOR]

En este artículo me gustaría proponer una lectura del fenómeno del deporte contemporáneo, desde la perspectiva del magistral Homo Ludens, obra del filósofo holandés publicado originalmente en 1938. Para esto, después de una breve presentación del autor y su obra, se exploran algunas condiciones de posibilidad de la existencia del principio del juego en el deporte moderno. Para Huizinga, el "espíritu del juego" encabeza las principales manifestaciones de la cultura humana en todas las épocas y sociedades. Sin embargo, este principio se estaría pervirtiendo en el mundo moderno, donde el trabajo asume aspectos de un juego (el ganar de los concurrentes, vencer el récord de las ventas) y el mundo del juego asume el carácter de trabajo (atletas profesionales, negocios, contratos, patrocinadores). ¿Como pensaría la perspectiva humanista y libertaria de Huizinga sobre el juego el mundo de los deportes contemporáneos? O, dicho de otro modo, ¿hay espacio para la práctica de ocio creativo y humanización en el mundo del deporte?

Background: The aim of this study was to characterize the genetic etiology in a patient who presented with permanent neonatal diabetes at 2 months of age., Methodology/principal Findings: Regulatory elements and coding exons 2 and 3 of the INS gene were amplified and sequenced from genomic and complementary DNA samples. A novel heterozygous INS mutation within the terminal intron of the gene was identified in the proband and her affected father. This mutation introduces an ectopic splice site leading to the insertion of 29 nucleotides from the intronic sequence into the mature mRNA, which results in a longer and abnormal transcript., Conclusions/significance: This study highlights the importance of routinely sequencing the exon-intron boundaries and the need to carry out additional studies to confirm the pathogenicity of any identified intronic genetic variants.

The effect of Botulinum Toxin type A (BoNT/A) on pain and neurogenic vasodilatation induced by application to the human skin of thermal stimuli and capsaicin was evaluated in a double blind study. A capsaicin cream (0.5 ml of a 0.075%) was applied to the skin of both forearms of eighteen subjects randomly pretreated with either BoNT/A (Botox) or 0.9% saline (NS). Capsaicin was applied to a skin area either inside (protocol A) or adjacent to the BoNT/A treated area (protocol B). Pre-treatment with BoNT/A did not affect thermal-specific and thermal-pain thresholds (by quantitative sensory testing). However, capsaicin-induced pain sensation (by a visual analogue scale), flare area (by acetate sheet) and changes in cutaneous blood flow (CBF, by laser Doppler flowmetry) were reduced when capsaicin was administered inside (protocol A) the BoNT/A treated area. In Protocol B, capsaicin-induced pain was unchanged, and capsaicin-induced flare/increase in CBF were reduced only in the area treated with BoNT/A, but not in the BoNT/A untreated area. Results indicate that (i) BoNT/A reduces capsaicin-induced pain and neurogenic vasodilatation without affecting the transmission of thermal and thermal-pain modalities; (ii) reduction in capsaicin-induced pain occurs only if capsaicin is administered into the BoNT/A pretreated area; (iii) reduction in neurogenic vasodilatation by BoNT/A does not contribute to its analgesic action. BoNT/A could be tested for the treatment of conditions characterised by neurogenic inflammation and inflammatory pain.

Objective: To assess the value of clinical (House-Brackmann grading) and neurophysiological (conventional electroneurography) monitoring of the facial nerve before and after (at day 10 and day 80) microsurgical parotidectomy in a group of patients with parotid tumors., Study Design and Setting: From January 7, 1999, to February 27, 2001, 33 patients were evaluated for parotid neoplasms confirmed by cytologic examination: 27 were benign and 6 were malignant epithelial tumors. All patients underwent preoperative electroneurography of the affected side and the normal contralateral side., Results: Preoperatively, 27 of 33 patients with benign lesions had normal facial nerve function on clinical and neurophysiological evaluation, while 3 of 6 patients with malignant lesions showed compound muscle action potential abnormalities of amplitude and latency, in the absence of facial nerve deficits. At the first postoperative evaluation, 2 of 6 patients with epithelial cancer and 4 of 27 patients with benign tumors had an absence of voluntary activity and compound muscle action potentials after nerve stimulation at the stylomastoid foramen; 1 patient with a malignant lesion and 5 patients with benign tumors had a transient facial palsy with amplitude reduction or latency prolongation of compound muscle action potential. This abnormality persisted in 2 of 27 patients at the second evaluation performed at day 80 after surgery. In 2 of 6 patients with malignant lesions, the day-80 electroneurogram showed a complete absence of nerve conduction., Conclusion: Electroneurography is a sensitive tool for monitoring clinically silent facial nerve function deficits in the context of preoperative tumor-induced damage and postsurgical early and late follow-up of nerve function.

Objectives: Botulinum neurotoxin serotype A (BoNT/A) is a valid therapy for dystonia but repeated BoNT/A injections may induce a clinical immuno-resistance that could be overcome by using other BoNT serotypes. In vitro experiments and our preliminary investigations in vivo, indicate that botulinum neurotoxin serotype C (BoNT/C) could be an effective alternative to BoNT/A. Moreover, in cultured neurons 'in vitro' BoNT/C has been reported to be more toxic than BoNT/A., Methods: To verify this possibility, we compare the effect of BoNT/C and BoNT/A on the motor units count in humans by using the electrophysiological motor unit number estimation (MUNE) technique ('multiple point nerve stimulation'). Preliminarily, BoNT/C and BoNT/A dosage was calibrated in a mouse hemidiaphragm neuromuscular junction preparation. Subsequently, 8 volunteers were treated with 3IU of BoNT/C in the extensor digitorum brevis muscle of one foot and 3IU of BoNT/A in the contralateral one. Other 4 subjects were similarly injected at higher doses (10IU of BoNT/C or BoNT/A) to detect a possible dose-toxic effect., Results: In both groups, no statistically significant variations in MUNE counting or single motor unit potential size were detected after 4 months from injections, when it was evident a recovery from the BoNTs blockade., Conclusions: We conclude that BoNT/C, similarly to BoNT/A, is safe and effective in humans and it could be proposed for a clinical use.

Background: Exertional heat illness (EHI) is a recurring problem in military training resulting in loss of manpower and training effectiveness. A scientific approach to this problem requires quantitative analysis of factors related to its occurrence., Methods: Review of clinic and hospital records identified all cases of EHI occurring among 217,000 Marine Corps recruits (90% male, 80% age 18-20 yr) entering 12-week basic training at Parris Island, SC during 1982-1991., Results: There were 1454 cases, 89% males and 11% females; 11% of male and no female cases were hospitalized. The majority (88%) of cases occurred during May-September, with a peak rate of 2% of recruits in summer. Most of the cases occurred during the cooler early morning hours when recruits performed strenuous exercise. During 0700-0900 hours the rate of heat casualties increased substantially as the Wet Bulb Globe Temperature Index (WBGT) increased, beginning at levels as low as 65 degrees F. EHI rates increased 26- and 39-fold at WBGT 75- < 80 degrees F (over baseline rates at < 65 degrees F) for immediate and prior day exposures, respectively. Exposure to WBGT of 80 + degrees F was infrequent (25%) among the early morning cases at the time of illness, while it was common (87%) on the day prior to illness, suggesting a lasting effect of heat exposure., Conclusions: Risk for EHI in military training increases markedly as WBGT levels rise above 65 degrees F; cases occur primarily with strenuous exercise (e.g., running); and heat stress exposure on prior days may be important.

The paper describes 8 cases of delayed haemorrhagic disease caused by vitamin K deficiency, occurring from 16 days to 3 months after birth and observed in 1982-87. All these infants were breast fed and had received no vitamin K prophylaxis. On the basis of these findings, the preventive role of vitamin K in breast fed infants is emphasised.