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It is known that chronic ethanol (EtOH) consumption leads to hypertension development and has been associated with deleterious effects on the cardiovascular system. Whether this condition alters calcium (Ca2+) signaling and exocytosis in adrenal chromaffin cells (CCs) as the case is for genetic hypertension, is unknown. We explored this question in four randomized experimental groups, male Wistar Kyoto (WKY/EtOH) and Spontaneously Hypertensive (SHR/EtOH) rats were subjected to the intake of increasing EtOH concentrations (5-20%, for 30 days) and their respective controls (WKY/Control and SHR/Control) received water. WKY/EtOH developed hypertension and cardiac hypertrophy; blood aldehyde dehydrogenase (ALDH) and H2O2 were also augmented. In comparison with WKY/Control, CCs from WKY/EtOH had the following features: (i) depolarization and higher frequency of spontaneous action potentials; (ii) decreased Ca2+ currents with slower inactivation; (iii) decreased K+ currents; (iv) augmented K+-elicited cytosolic Ca2+ transients ([Ca2+]c); (v) enhanced K+-elicited catecholamine release. These cardiovascular, blood and CCs changes were qualitatively similar to those undergone by SHR/Control and SHR/EtOH. The results suggest that the hypertension elicited by chronic EtOH has pathogenic features common to genetic hypertension namely, augmented [Ca2+]c transients and catecholamine release from their CCs.

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From experiments performed at room temperature, we know that the buffering of Ca(2+) by mitochondria contributes to the shaping of the bulk cytosolic calcium transient ([Ca(2+)]c) and secretion transients of chromaffin cells stimulated with depolarizing pulses. We also know that the mitochondrial Ca(2+) transporters and the release of catecholamine are faster at 37°C with respect to room temperature. Therefore, we planned this investigation to gain further insight into the contribution of mitochondrial Ca(2+) buffering to the shaping of [Ca(2+)]c and catecholamine release transients, using some novel experimental conditions that have not been yet explored namely: (1) perifusion of bovine chromaffin cells (BCCs) with saline at 37°C and their repeated challenging with the physiological neurotransmitter acetylcholine (ACh); (2) separate blockade of mitochondrial Ca(2+) uniporter (mCUP) with Ru360 or the mitochondrial Na(+)/Ca(2+) exchanger (mNCX) with CGP37157; (3) full blockade of the mitochondrial Ca(2+) cycling (mCC) by the simultaneous inhibition of the mCUP and the mNCX. Ru360 caused a pronounced delay of [Ca(2+)]c clearance and augmented secretion. In contrast, CGP37157 only caused a tiny delay of [Ca(2+)]c clearance and a mild decrease in secretion. The mCC resulting in continued Ca(2+) uptake and its release back into the cytosol was interrupted by combined Ru360 + CGP37157 (Ru/CGP), the protonophore carbonyl cyanide-p-trifluoromethoxyphenylhydrazone, or combined oligomycin + rotenone (O/R); these three treatments caused a mild but sustained elevation of basal [Ca(2+)]c that, however, was not accompanied by a parallel increase in basal secretion. Nevertheless, all treatments caused a pronounced augmentation of ACh-induced secretion, with minor changes of the ACh-induced [Ca(2+)]c transients. Combined Ru/CGP did not alter the resting membrane potential in current-clamped cells. Additionally, Ru/CGP did not increase basal [Ca(2+)]c near subplasmalemmal sites and caused a mild decrease in the size of the readily releasable vesicle pool. Our results provide new functional features in support of the view that in BCCs there are two subpopulations of mitochondria, M1 underneath the plasmalemma nearby exocytotic sites and M2 at the core cell nearby vesicle transport sites. While M1 serves to shape the ACh-elicited exocytotic response through its efficient Ca(2+) removal by the mCUP, M2 shapes the lower [Ca(2+)]c elevations required for new vesicle supply to the exocytotic machinery, from the large reserve vesicle pool at the cell core. The mCUP of the M1 pool seems to play a more prominent role in controlling the ACh responses, in comparison with the mNCX.

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Objective. To describe the Mesial Temporal Lobe Sclerosis (MTS), in relation to its anatomical, clinical, iconographic, neurophysiologic, neuro psychologic, and surgical aspects, in reference to the epilepsy cases that needed a surgical resolution. Additionally, it’s realized a statistical analysis of our series and its results.Material and methods. From the series of 469 patients (115 adults and 354 children) operated on between 1989 and 2007, at National Pediatrics . Dr. Juan Garrahan, FLENI, Dr. Cosme Argerich, and Prof. Dr. R. Rossi Hospitals; who harbored RefractoryEpilepsy ; were analyzed 91 cases (19,4%) with the diagnosis of MTS; 38 patients belong to the pediatric group and 53 were adults. Results. The results were evaluated by the Engel score. Applying this classification, our population of patients showed thenext pattern of distribution: 69 (75,8%) are in Engel’s class IA, from this group, 36 (52,2%) are children, and 33 (47,8%), adults; 4 adults patients;( 4,4%) are in Engel’s class IB, 3 patients (3,3%) in Engel’s class IC; 1 (in Engel’s class ID(1,1%); 4 adults in Engel’s class IIA (4,4%); 5 in Engel’s class IIB (5;5%) and 3 (3,3%) in Engel’s class IVA; from then, one patient was a child, and underwent the implantation of VNS, the rest were adults. One adult patient committed suicide, one year after surgery (was in Engel’s class IA). One patient is on his first post operative year,and then couldn’t been included in statistical analysis, because follow up wasn’t enough. Conclusion. The MTS is the paradigm of Refractory Epilepsy inthe adult population, and in the pediatric subgroup involved a significant percentage: the presurgical evaluation must be exhaustive for adequate selection of cases. The extent of resection should be done with high degree of selectivity. The early diagnosis and treatment can obtain a high index of good results without ictal phenomena and the absence of necessity of antiepileptic drugs.

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Objective: To describe the presentation and the management of the Mesial Temporal Sclerosis (ETM) in adult patients and to evaluate the results of the presented series. Description: the authors selectioned 3 cases among 53 adults who underwent surgical treatment with ETM diagnosis. Case 1: female patient, 32 years old. Antecedents of complex partial crisis since 6 years old, some of the crisis related to febrile episodes. Aura related like unpleasent gastroesophageal sensation, break of contact, right hand dystonia, cephalic turn to right and oroalimentary and manual automatism. RMI and EEG-video: injury compatible with left ETM. Case 2: male patient, 24 years old. Antecedents of complex partial crisis since 13 years old. Breack of contact, verbal automatisms (repeats unintelligible sounds) and sensation of postictal sikness. RMI: increase of signal (FLAIR) in both hippocampus, impressing right atrophy. EEG-video with profund electrodes implanted: start of the crisis on a right mesial temporal level. Case 3: female patient, 21 years old. Antecedents of complex partial crisis since 12 years old. Complex partial crisis with bimanual and oroalimentary automatisms with an episode of generalization. RMI and EEG-video: injury compatible with right ETM. Intervention: case 1 and 2 were resolved by the realization of an anteromesial resection of Spencer. In case 3 a selective amygdalo hippocampectomy was practiced. Conclusion: ETM is the paradigm of the refractory epilepsy in an adult population. Precocious diagnosys and treatment allow to obtain a high index of cure with small amount of significant sequels.

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Objective: To analyze the biomechanical and anatomical factors and the surgical treatment and outcome in cervical degenerative spondylolisthesis. Method: Between 1978 and 2003, 223 patients underwent surgery for cervical spondylotic myelopathy, 41 patients presented with degenerative subaxial subluxation. According to the Nurick scale, 26 were grade 2, 14 were grade 3 and 1 was grade 4. Those with degenerative subluxation were older compared to those who had only spondylotic myelopathy (63 vs 13 years). The former also corresponded to higher grades of the Nurick scale. All patients underwent static and dynamic plain radiographs, and MRI. We found 29 subluxations of one level, 11 patients with affection of two levels and 1 with three levels. 33 patients had unstable subluxations. The most commonly affected levels were C3-C4 and C4-C5. In all the cases, an anterior approach with autogenous bone graft and locking plate was performed. REsults: After surgical teatment, 21 grade 2 patients improved one grade, while 5 improved two grades; 9 grade 3 patients improved one grade and 1 two grades; the grade 4 patient improved one grade. Conclusion: Cervical degenerative subluxation is seen in older patients, usually associated with severe myelopathy and spondylotic changes. The cervical instability is more common in the C3-C4 and C4-C5 segments. In all the cases of our group there was a loss of cervical lordosis or kyphosis with ankylosis of the lower cervical spine. The anterior approach with autogenous bone graft and locking plate, allowed spinal cor decompression and cervical fusion (AU)

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Objective: To analyze the biomechanical and anatomical factors and the surgical treatment and outcome in cervical degenerative spondylolisthesis. Method: Between 1978 and 2003, 223 patients underwent surgery for cervical spondylotic myelopathy, 41 patients presented with degenerative subaxial subluxation. According to the Nurick scale, 26 were grade 2, 14 were grade 3 and 1 was grade 4. Those with degenerative subluxation were older compared to those who had only spondylotic myelopathy (63 vs 13 years). The former also corresponded to higher grades of the Nurick scale. All patients underwent static and dynamic plain radiographs, and MRI. We found 29 subluxations of one level, 11 patients with affection of two levels and 1 with three levels. 33 patients had unstable subluxations. The most commonly affected levels were C3-C4 and C4-C5. In all the cases, an anterior approach with autogenous bone graft and locking plate was performed. REsults: After surgical teatment, 21 grade 2 patients improved one grade, while 5 improved two grades; 9 grade 3 patients improved one grade and 1 two grades; the grade 4 patient improved one grade. Conclusion: Cervical degenerative subluxation is seen in older patients, usually associated with severe myelopathy and spondylotic changes. The cervical instability is more common in the C3-C4 and C4-C5 segments. In all the cases of our group there was a loss of cervical lordosis or kyphosis with ankylosis of the lower cervical spine. The anterior approach with autogenous bone graft and locking plate, allowed spinal cor decompression and cervical fusion

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Objective: To describe an algorithm for surgical management of cervical spine RA. Methods: RA cases treated by the senior authors from 1978 to 2003 have been analyzed. An algorithm for surgical management of the different forms of this pathology is proposed. Results: Cervical spine involvement by RA includes atlantoaxial subluxation, settling of the odonteid process, and suaxial subluxation. Surgical treatment should be established immediately after is radiological diagnosis. The optimal approach is a posterior one in every case, followed by an anterior approach when periodontal pannus, superior migration of the odontoid process, or subaxial subluxation are associated with an anterior compression. Conclusion: This algorithm is a useful guide to the treatment of spine RA (AU)

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Objective: To describe an algorithm for surgical management of cervical spine RA. Methods: RA cases treated by the senior authors from 1978 to 2003 have been analyzed. An algorithm for surgical management of the different forms of this pathology is proposed. Results: Cervical spine involvement by RA includes atlantoaxial subluxation, settling of the odonteid process, and suaxial subluxation. Surgical treatment should be established immediately after is radiological diagnosis. The optimal approach is a posterior one in every case, followed by an anterior approach when periodontal pannus, superior migration of the odontoid process, or subaxial subluxation are associated with an anterior compression. Conclusion: This algorithm is a useful guide to the treatment of spine RA

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