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E Ramos

Publications and source records attributed to E Ramos.

At least 37 records · Page 2Linked to original sources

[Discrepancy between imaging and neurophysiology in deep brain stimulation of medial pallidum and subthalamic nucleus in Parkinson's disease].

OBJECTIVE: The objective of this work is to assess the discrepancy in distance between the target chosen by magnetic resonance imaging (MRI) and the final electrode placement after intraoperative microrecording in patients submitted to deep brain stimulation (DBS) for alleviating the Parkinson's disease (PD). METHODS: Thirty patients with PD and motor complications were operated with stereotactic surgery by MRI and microrecording. In 19 patients, the target chosen was the subthalamic nucleus (STN) and in 11 others the target was globus pallidus internus (GPi). In this work it is considered that the electrode has a current field below usual parameters of 1.5 mm radius. Consequently, when the distance error between the final physiological target and the MRI target, is between 1.5 and 3 mm was considered as partial discrepancy and distances of 3 mm or more were considered as total discrepancy. RESULTS: Partial discrepancy for STN and GPi were in 25 and 33% of the cases respectively and total discrepancy was 57 and 42% for each nucleus. The average distance error between both targets, final and image, for X stereotactic coordinate (mediolateral distance) was 1.54 mm for STN and 0.8 mm for GPi. The average distance for Y coordinate (anteroposterior distance) was 2.3 mm for STN and 2.2 mm for GPi. CONCLUSION: There is a significant discrepancy between the final physiological target after microrecording and the target chosen by MRI during surgery for alleviating PD that may induce variations or absence of clinical efficacy in parkinsonian patients submitted to the DBS surgery. Authors suggest the necessity of the microelectrode recording in order to reach the surgical target with the best clinical condition.

Electric Stimulation↗

Results of 3-year phase III clinical trials with daclizumab prophylaxis for prevention of acute rejection after renal transplantation.

BACKGROUND: Daclizumab (Zenapax, Roche Pharmaceuticals), a humanized monoclonal antibody directed against the alpha chain of the interleukin 2 receptor, has been shown to reduce the incidence of acute rejection at 6 months after renal transplantation in two phase III clinical trials. This report presents the combined 1- and 3-year outcomes of kidney transplant recipients who participated in these two phase III clinical trials. METHODS: Data from two multicenter, randomized, placebo-controlled trials were evaluated with regard to graft survival, patient survival, incidence of malignancies (including lymphoma), renal function (serum creatinine and glomerular filtration rate [GFR]), and current maintenance immunosuppressive regimen. In addition, the impact of acute rejection and acute rejection requiring treatment with antilymphocyte therapy upon 3-year graft survival was evaluated. Daclizumab was compared to placebo on a background of cyclosporine (CsA), azathioprine, and corticosteroids (triple therapy, TT) or CsA and corticosteroids (double therapy, DT). RESULTS: Treatment with daclizumab in the pooled analysis demonstrated a significant reduction in the incidence of biopsy-proven acute rejection episodes at 12 months posttransplant (43% vs. 28%, P<0.001). The 3-year graft survival was not significantly different between placebo and daclizumab-treated patients in the TT trial (83% vs. 84%) or in the DT trial (78% vs. 82%). Pooled patient survival was excellent in both placebo- (91%) and daclizumab- (93%) treated patients. The incidence of malignancies or posttransplant lymphoproliferative disorder (PTLD) in placebo- versus daclizumab-treated groups was comparable in both clinical trials. Renal function was similar between placebo- and daclizumab-treated groups in both the TT and DT trials. The occurrence of delayed graft function, acute rejection requiring antilymphocyte therapy at 6 months, and acute rejection at 12 months posttransplant were associated with decreased graft survival rates at 3 years posttransplant. CONCLUSIONS: The beneficial effect of daclizumab prophylaxis upon the incidence of acute rejection after renal transplant with TT or with DT was not associated with adverse clinical sequelae, including the development of PTLD, at 3 years posttransplant. There was no beneficial effect of daclizumab on graft survival at 3 years, but the trial was inadequately powered to detect this. Both studies showed excellent graft and patient survival at 3 years.

Acute Disease↗

Daclizumab (humanized anti-IL2Ralpha mAb) prophylaxis for prevention of acute rejection in renal transplant recipients with delayed graft function.

BACKGROUND: The purpose of this retrospective study was to determine the benefits of daclizumab, (Zenapax, Roche Pharmaceuticals) a humanized anti-interleukin-2Ralpha (IL-2Ralpha) monoclonal antibody, for prevention of acute rejection in renal transplant recipients with delayed graft function (DGF). METHODS: Data from two multicenter randomized placebo-controlled trials were pooled. DGF was defined by urine output <30 cc/hour, decline in serum creatinine of <0.5 mg/dl, or the need for dialysis within the first 24 hours after transplantation. RESULTS: At one year posttransplantation, the incidence of biopsy-proven acute rejection in patients with DGF was reduced from 44% in the placebo group to 28% in the daclizumab group. (P=0.03) Prophylaxis with daclizumab also delayed the onset of the first biopsy-proven acute rejection episode in patients with DGF from 29+/-43 days in the placebo group to 73+/-70 days in the daclizumab group. (P=0.004) The graft survival rates in patients with DGF at 1 year posttransplantation were 78% in the placebo group and 82% in the daclizumab treated group. (P=ns) Three patients in the placebo-treated group with DGF experienced graft loss due to acute rejection, whereas no patients in the daclizumab-treated group with DGF had graft loss due to acute rejection. The 1-year patient survival rate in those with DGF in the placebo and daclizumab groups were 93% and 98%, respectively. (P=ns) CONCLUSIONS: Daclizumab effectively reduced the incidence and delayed the onset of biopsy-proven acute rejection in this high-risk subgroup of patients with DGF after renal transplantation. Graft and patient survival rates were similar between placebo- and daclizumab-treated patients with DGF.

Acute Disease↗

The impact of donor age on liver transplantation: influence of donor age on early liver function and on subsequent patient and graft survival.

BACKGROUND: The urgent need to increase the organ donor pool has led to the expansion of criteria for donor selection. The aim of this study was to analyze the influence of donor age on early graft function, subsequent graft loss, and mortality after liver transplantation (LT). METHODS: Data on LT were evaluated retrospectively in a population-based cohort of 400 LTs in 348 patients. Of these, 21 (5%) were from donors >70 years old. Pretransplantation donor and recipient characteristics and the evolution of recipients were analyzed. The influence of donor age as a risk factor was assessed using univariate and multivariate analyses. RESULTS: Actuarial graft survival was 89% at 1 month after LT, 81% after 6 months, and 59% after 60 months. Multivariate analysis demonstrated that only donor age (>70 years old) was associated with a higher risk of long-term graft loss (relative risk [RR]=1.4, 95% confidence interval [CI]=1-1.9; P=0.03) and mortality (RR=1.7, 95% CI=1.2-2.3; P=0.01). Graft survival of septuagenarian livers was 80% at 1 month after LT, 56% after 6 months, and 25% after 54 months. Actuarial survival analysis (Kaplan-Meier curves) also demonstrated worse evolution in recipients of livers from old donors (log-rank test, P<0.001). CONCLUSIONS: Advanced donor age is associated with lower graft and recipient survival.

Adolescent↗

[Clinical study of 437 consecutive hepatectomies].

BACKGROUND: The aim of this prospective study was to analyze the risk of liver resection in unselected patients. PATIENTS AND METHOD: From 1990 to 2000, 437 consecutive hepatectomies were performed in our center. Most frequent indications were liver metastases (n = 288), hepatocellular carcinoma (n = 62), Klatskin tumor (n = 17), gallblader carcinoma (n = 139) and other malignant tumors (n = 6). The indication was a benign tumor in 51 patients. In 357 cases the liver parenchyma was normal, 51 patients had an underlying cirrhosis and 17 patients had an obstructive jaundice. RESULTS: Overall mortality was 3.6% (15 cases). Mortality in benign tumors was lacking. The prevalence of postoperative complications was 43.9%, which was mainly influenced by malignancy (46.9% vs 21.6%, p = 0.001) and type of tumor (Klastkin tumor, p # 0.001). Major liver resection (p < 0.001), blood transfusion (p < 0.001), age over 60 years (p = 0.001) and the type of hepatectomy (p < 0.001) also increased significantly the morbidity. The prevalence of biliary fistula was 11.2%, which was mainly related to the type of hepatectomy (major hepatectomy; p = 0.002) and a biliary-enteric anastomosis (p < 0.001). The prevalence of hepatic insufficiency was 3.6%, and chief risk factors for its development were underlying liver disease and major liver resection (p = 0.017). CONCLUSIONS: Mortality after hepatectomy in experienced centers is low. Morbidity is mainly related to the amount of parenchyma resected, type of hepatectomy, underlying liver disease and associated procedures. Liver resection should be performed preferentially in centers with high volume by specialized surgeons.

Aged↗

Multicenter trial exploring calcineurin inhibitors avoidance in renal transplantation.

BACKGROUND: The adoption of calcineurin inhibitors (CNI) as the mainstay of immunosuppression has resuited in a significant decrease of acute rejection and improvement of short-term graft survival. However, because of the irreversible nephrotoxicity associated with the chronic use of the CNI, the magnitude of the improvement of long-term graft survival has been more modest. Therefore, an effective immunosuppression regimen that does not rely on CNI may result in improvement of long-term outcome and simplification of the management of transplant recipients. METHODS: Ninety-eight patients of primary cadaver or living donor kidneys at low immunologic risk were enrolled in a CNI avoidance study. The immunosuppression regimen consisted of daclizumab, a humanized monoclonal antibody that binds to the alpha chain of the interleukin-2 receptor (IL-2Ralpha), administered for a total of five doses at biweekly intervals; 3 gm/day mycophenolate mofetil for the first 6 month and 2 gm thereafter; and conventional corticosteroid therapy. Patients who underwent rejection episodes could be started on CNI. The primary efficacy end-point was biopsy-proven rejection during the first 6 months posttransplant. RESULTS: Biopsy-proven rejection was diagnosed in 48% of patients during the first 6 months after transplantation. The majority of rejection episodes were Banff grade I and IIA and were fully reversed with corticosteroid therapy. The median time to the first biopsy-proven rejection among patients who experienced this event during the first 6 months was 39 days. In 22 patients with delayed graft function, the proportion of patients with biopsy-proven rejection was 50% at 6 months. However in the first 2 weeks posttransplant, only 1 of 22 patients with delayed graft function developed biopsy-proven rejection. At 1 year, patient survival was 97% and graft survival was 96%. Only two grafts were lost secondary to rejection. At 1-year posttransplant, 62% of patients had received CNI for more than 7 days. At 1-year posttransplant, the mean serum creatinine in the nonrejectors with no CNI use was 113 micromol/L (95%, confidence interval [CI], 100.7 to 125.3 micromol/L) and in the rejectors or patients with CNI use (more than 7 days) was 154 micromol/L (95% CI, 135.0 to 173.0 micromol/L). In selected patients with rejection, analysis of circulating and intragraft lymphocytes revealed complete IL-2Ralpha saturation. CONCLUSIONS: This CNI avoidance study in immunologic low-risk patients, while only partially successful in preventing acute rejection, provided benefits to a sizable minority of patients who have not required chronic CNI therapy. However, wide acceptance of a CNI-sparing immunosuppression regimen may require a lower rate of acute rejection, possibly through the addition of a non-nephrotoxic dose of CNI. However, because complete IL-2Ralpha blockade was present during rejection, it can be assumed that alternative pathways, such as IL-15, may be responsible for the rejection; thus, the incorporation of non-nephrotoxic immunosuppressive agents, such as sirolimus, may provide a more strategic approach.

Antibodies, Monoclonal↗

[Sequential liver transplantation: description of the first three patients in Spain].

BACKGROUND: Domino or sequential liver transplantation (DTXL) is a kind of living donor transplant, which was proposed in 1993 and performed for the first time in 1995; later on, more than 45 have been reported. The liver from a patient with familial amyloidotic polyneuropathy(FAP) is used to another patient aged more than 60 with hepatic disease generally cancer, because FAP livers are anatomically and functionally normal except for the synthesis of the systemic TTR variant which only could generate FAP in the recipient after more than 8 years. PATIENTS AND METHOD: The three first cases of DTXL performed in Spain are presented. The donors were FAPTTRMet30 patients from the Major can focus. The first recipient showed severe hyperinsulinism due to metastatic liver from malignant insulinoma; the others had hepatocellular carcinoma on a cirrhotic liver. RESULTS: During the post operatory period liver function of recipients was perfect,and hyperinsulinism disappeared in the first; this patient died after 10 days by sepsis whereas the others showed normal liver function, no recurrent cancer nor onset of FAP. The donors outcome was normal with perfect liver function. CONCLUSIONS: Based on our results, in agreement with previous reports, we conclude that DTXH is valid procedure for a selected patient group. In addition they increase the pool of liver donors and therefore diminish the overloaded waiting lists.

Adult↗

Language disorders as a window on universal grammar: an abstract theory of agreement for IP, DP, and V-PP.

A new concept of Agreement (AGR) has been represented as a Formal Feature that can appear in a wide range of different configurations (Chomsky, 1998). A case study from language disorders supports and extends this abstract concept. The child shows no agreement in Inflectional Phrase me can and Determiner Phrase them eyes. We then extend the notion of AGR to include verb-Prepositional Phrase relations, where the child also systematically avoids certain prepositions (go beach). The analysis is supported by intuitional data from compounds (sweep with broom --> broom-swept). We also define a systematic notion of Possible deficit as a premature fixation of functional items which normally require additional Phi-features. The notion of Maximization of Formal Features then emerges as a significant feature of learnability from both a normal and disordered perspective.

Child↗