Use of acute peritoneal dialysis catheters for intraperitoneal chemotherapy instead of the semipermanent/permanent Tenkhoff catheters

Intraperitoneal chemotherapy was administered to 13 patients with peritoneal carcinomatosis, using acute peritoneal dialysis catheters immediately before the administration of the chemotherapy. A total of 59 cycles were administered, with insertion of the corresponding catheter. There were no inflow or outflow problems and no insertion-related complications. With the removal of the catheter after its use, there is no risk of abdominal infections.     

Use of stereotactic PET images in dosimetry planning of radiosurgery for brain tumors: clinical experience and proposed classification.

We developed a technique that allows the routine integration of PET in stereotactic neurosurgery, including radiosurgery. We report our clinical experience with the combined use of metabolic (i.e., PET) and anatomic (i.e., MRI and CT) images for the radiosurgical treatment of brain tumors. We propose a classification describing the relative role of the information provided by PET in this multimodality image-guided approach. METHODS: Between December 1999 and March 2003, 57 patients had stereotactic PET as part of their image acquisition for the planning of gamma knife radiosurgery. Together with stereotactic MRI and CT, stereotactic PET images were acquired on the same day using either (18)F-FDG or (11)C-methionine. PET images were imported in the planning software for the radiosurgery dosimetry, and the target volume was defined using the combined information of PET and MRI or CT. To analyze the specific contribution of the PET findings, we propose a classification that reflects the strategy used to define the target volume. RESULTS: The patients were offered radiosurgery with PET guidance when their tumor was ill-defined and we anticipated some limitation of target definition on MRI alone. This represents 10% of the radiosurgery procedures performed in our center during the same period of time. There were 40 primary brain lesions, 7 metastases, and 10 pituitary adenomas. Abnormal PET uptake was found in 62 of 72 targets (86%), and this information altered significantly the MRI-defined tumor in 43 targets (69%). CONCLUSION: The integration of PET in radiosurgery provides additional information that opens new perspectives for the optimization of the treatment of brain tumors.     

Regular physical activity increases glutathione peroxidase activity in adolescents with Down syndrome.

OBJECTIVE: The present study was designed to determine the influence of a 12-week exercise program on the activity of erythrocyte glutathione peroxidase (GPX) in adolescents with Down syndrome. DESIGN: An interventional study with before-after comparison. SETTING: Sport Medicine School, University of Cadiz (Andalusia, Spain). PATIENTS: Thirty-one male adolescents (16.3+/-1.1) with Down syndrome. None of them suffered acute medical problems at that moment and had not taken part in any physical activity program in the last 6 months. INTERVENTION: A 12-week training program with 3 days per week, consisting of warm up (15 min) followed by a main part (20 to 35 min) at a work intensity of 60% to 75% of peak heart rate (HRmax=194.5-[0.56xage]) and by a cool-down period (10 min). MAIN OUTCOME MEASUREMENT: Erythrocyte activity of GPX. RESULTS: Preexercise and postexercise GPX activity in adolescents with Down syndrome were 24.8+/-3.1 [23.1 to 26.5] U/g hemoglobin and 29.3+/-2.9 [28.1 to 30.5] U/g hemoglobin, respectively. When compared with baseline values it was increased significantly (24.8+/-3.1 vs. 29.3+/-2.9; P=0.011). CONCLUSION: Regular exercise increased significantly GPX activity. Further studies are required to assess the behavior of other antioxidant enzymes to highlight potential benefits of regular exercise in redox metabolism.     

Involvement of IL-1beta in acute stress-induced worsening of cerebral ischaemia in rats.

Stress is known to be one of the risk factors of stroke. Most of the knowledge on the effects of stress on cerebrovascular disease in humans is restricted to catecholamines and glucocorticoids effects on blood pressure and/or development of atherosclerosis. However, few experimental studies have examined the possible mechanisms by which stress may affect stroke outcome. We have used an acute stress protocol consisting of the exposure of male Fischer rats to an acute, single exposure immobilisation protocol (6 h) prior to permanent middle cerebral artery occlusion (MCAO), and we have found that stress worsens behavioural and neurological outcomes and increased infarct size after MCAO. The possible regulatory role of the TNFalpha and IL-1beta was studied by looking at the release of these cytokines in brain. The results of the present study showed an increase in IL-1beta release in cerebral cortex after exposure to acute stress. Brain levels of IL-1beta are also higher in previously stressed MCAO rats than in MCAO animals without stress. Pharmacological blockade of IL-1beta with an antibody anti-IL-1beta led to a decrease in the infarct size as well as in neurological and behavioural deficits after MCAO. In summary, our results indicate that IL-1beta, but not TNFalpha, accounts at least partly for the worsening of MCAO consequences in brain of rats exposed to acute stress.     

Mortality risk associated with ejection fraction differs across resting nuclear perfusion findings.

BACKGROUND: Left ventricular ejection fraction (LVEF) is a significant predictor of morbidity and death. The nuclear summed rest score (SRS) measures myocardial perfusion defects and provides prognostic information, but its effects on long-term outcomes are not fully established. Moreover, information regarding the potential interaction between these 2 covariates is limited. The purpose of this study was to determine whether the mortality risk associated with LVEF is the same across all values of SRS in a population undergoing evaluation for ischemic heart disease. METHODS AND RESULTS: We examined 3,187 patients who underwent cardiac catheterization and perfusion single photon emission computed tomography imaging with a maximum follow-up of 8.1 years and median follow-up of 3.1 years. Cox proportional hazards modeling showed that increasing nuclear SRS and decreasing LVEF were independently associated with a higher long-term mortality rate, with a clinically significant interaction between them (P = .032). Patients with a normal LVEF and a high SRS (greater perfusion abnormality) have a prognosis similar to those with a reduced LVEF. CONCLUSIONS: Resting perfusion studies provide prognostic information for long-term survival and significantly impact the interpretation of mortality risk associated with changes in LVEF. Patient prognostication, risk stratification, and future research using these variables should take this interaction into account.     

Vascular injury during anterior lumbar surgery.

BACKGROUND CONTEXT: With the number of anterior lumbar procedures expected to increase significantly over the next few years, it is important for spine surgeons to have a good understanding about the incidence of vascular complications during these operations. PURPOSE: To determine the incidence of vascular injury in 1,315 consecutive cases undergoing anterior lumbar surgery at various levels from L2 to S1. STUDY DESIGN/SETTING: Patients undergoing anterior lumbar surgery were studied. PATIENT SAMPLE: A total of 1,310 consecutive patients undergoing 1,315 anterior lumbar procedures between August 1997 and December 2002 were included in the study. OUTCOME MEASURES: All patients were evaluated for incidence of vascular injury during and immediately after surgery. METHOD: A concurrent database was maintained on all these cases. All the patients had distal pulse evaluation preoperatively. Patients with venous injuries were further analyzed to determine location and extent of injury, amount of blood loss, completion of the procedure and postoperative sequelae. Patients with pulse deficits or evidence of ischemia during or immediately after surgery were further analyzed in particular in relation to demographic, preoperative variables and management. RESULTS: Six patients were identified as having left iliac artery thrombosis (0.45%), and 19 had major vein lacerations (1.4%). CONCLUSION: This study shows that the incidence of vascular injury is relatively low (25 in 1,315 or 1.9%). Because only five of these patients experienced significant sequelae from the approach, it appears that anterior lumbar surgery is quite safe, although it must be carried out with utmost respect for the vessels to avoid possible catastrophic outcomes.     

Numerical method for weights adjustment in minimax multi‐model LQ‐control

The minimax linear quadratic problem, where ‘max’ is taken over a finite set of indices (models) and ‘min’ is taken over the set of admissible controls, is considered. The solution is obtained by the robust optimal control application. The control turns out to be a linear combination of the controls optimal for each individual model. This paper develops a numerical method for the optimal weights adjustment. An example shows a quick convergence of the proposed procedure. Copyright © 2007 John Wiley & Sons, Ltd.