1,721,088 research outputs found
Hypoglossal-facial anastomosis
No full textThe aim of this paper was to report on further experience with a new technique for reanimation of the facial nerve. This procedure allows a straight end-to-side hypoglossal-facial anastomosis without interruption of the 12th cranial nerve or the need for graft interposition. It is technically demanding and time consuming but offers an effective, reliable, and extraordinarily quick means of reinnervating the facial muscles, including the orbicularis oculi muscle, thus avoiding the need for a gold weight in the eyelid or a fascial sling
Motonuclear changes after cranial nerve injury and regeneration
No full textLittle is known about the mechanisms at play in nerve regeneration after nerve injury. Personal studies are reported regarding motonuclear changes after regeneration of injured cranial nerves, in particular of the facial and oculomotor nerves, as well as the influence that the natural molecule acetyl- L-carnitine (ALC) has on post-axotomy cranial nerve motoneuron degeneration after facial and vagus nerve lesions. Adult and newborn animal models were used. Massive motoneuron response after nerve section and reconstruction was observed in the motonuclei of all nerves studied. ALC showed to have significant neuroprotective effects on the degeneration of axotomized motoneurons. Complex quantitative, morphological and somatotopic nuclear changes occurred that sustain new hypotheses regarding the capacities of motoneurons to regenerate and the possibilities of new neuron proliferation. The particularities of such observations are described and discussed
Effects of levo-acetylcarnitine on second motoneuron survival after axotomy
No full textLittle is known about factors that regulate the survival of cranial motoneurons which project to peripheral targets. Various neurotrophic factors of central and peripheral origin have been isolated. In this study, we examined thirteen newborn Wistar rats to determine the effects of acetyl-L- carnitine treatment on the survival of motoneurons within the facial nucleus after transection of the facial nerve. Acetyl-L-carnitine was administered for 7 days in seven rats after nerve transection, while saline solution was injected in 6 rats used as controls. Both the motoneuron number and the motoneuron diameter were significantly higher in the facial nucleus of the rats treated with acetyl-L-carnitine than in the facial nucleus of the control rats. The results obtained suggest that acetyl-L-carnitine can rescue a substantial number of facial motoneurons from axotomy-induced cell death. Compared to neurotrophic factors, because of its simple molecular structure, acetyl-L-carnitine permits a sate oral and parenteral administration. It is suggested that acetyl-L-carnitine could be considered for use as a therapeutic agent in neurodegenerative disorders
Molecular basis of extended-spectrum beta-lactamase production in nosocomial isolates of Klebsiella pneumoniae from Mérida, Venezuela
No full textTwelve Klebsiella pneumoniae isolates resistant to expanded-spectrum cephalosporins and aztreonam, from patients with nosocomial septicaemia at the intensive care unit of the Andes University Hospital, Merida, Venezuela, were studied for production of extended-spectrum β-lactamase (ESβL) activity. All were also resistant to gentamicin, kanamycin, tetracycline and chloramphenicol but sensitive to cefoxitin, imipenem, amikacin and tobramycin. Production of ESβL activity was confirmed by restoring susceptibility to ceftazidime in the presence of clavulanic acid. All isolates carried an identical plasmid of approximately 87 kb. Resistance to β-lactams, aminoglycosides, tetracycline and chloramphenicol was lost en bloc after plasmid curing by treatment with acridine orange and was transferable en bloc to Escherichia coli by conjugation. Transconjugants always showed the same plasmid profile as that of Klebsiella donors. Isoelectric focusing analysis of the crude extracts of transconjugants showed in all cases, the presence of two β-lactamases of pI 5.4 and 8.2. Analysis of the plasmid carried by one of the transconjugants by means of hybridization assays, revealed the presence of both bla(TEM) and bla(SHV) determinants. Cloning and sequencing of each determinant identified them as bla(TEM-1) and bla(SHV-5), respectively, the latter being responsible for the ESβL activity. Results of this study indicate that ESβL determinants of the SHV-type carried by transferable elements, are spreading among nosocomial isolates of K. pneumoniae in Merida, Venezuela. (C) 2000 Published by Elsevier Science B.V. and International Society of Chemotherapy
O-arm in Endonasal Endoscopic Cranial Base Surgery. Technical Note on Initial Feasibility
No full textBackground: In transsphenoidal endoscopic cranial base surgery, a precise navigational support may be crucial. This is particularly evident when tumors extend to the parasellar region or in recurrent tumors whereas normal anatomy has been altered by previous surgery/radiotherapy. Methods: Previous unsatisfactory experiences with various navigation techniques in this type of surgery encouraged us to perform an endoscopic endonasal approach with an O-arm (Medtronic, Inc., Minneapolis, Minnesota, USA) assisted technique for the surgical treatment of 4 patients affected respectively by an orbital tumor and 3 cases of relapse of nonfunctioning pituitary adenoma, 1 of them localized in the infrasellar-clival region. Results: The system O-arm-StealthStation allows for merging intraoperative bone 3-D acquisition with preoperative computed tomography/magnetic resonance imaging and provides the surgeon with an extremely reliable operative navigational tool. Conclusions: This is the first report of an O-arm-assisted endoscopic surgery for cranial base tumors. Here we report on the feasibility and usefulness of such a new application of the O-arm: technical details, setting of the operating room, advantages, and limits of the method are also described. Our overall impression, considering the limited number of patients, is that use of the O-arm may be successfully extended to selected cases of cranial base tumors operated through an endoscopic endonasal approach
2. : Hypoglossal- Facial nerve anastomosis†in (Edts) Ramina R, Pires Aguir P.H., Tatagiba M, Sprinter-Verlag, Berlin Heidelberg 2008; cap 29 pp297305
No full text- …
