A Coupled FEM-BEM Approach for the Solution of the Free-Boundary Axi-Symmetric Plasma Equilibrium Problem

In this paper we present a coupled Finite Element Method – Boundary Element Method (FEM-BEM) approach for the solution of the free-boundary axi-symmetricplasma equilibrium problem. The proposed method, obtained from an improvementof the Hagenow-Lackner coupling method, allows to efficiently model the equilibriumproblem in unbounded domains by discretizing only the plasma region; the externalconductors can be modelled either as 2D or 3D models, according to the problem of interest. The paper explores different iterative methods for the solution of the nonlinearGrad-Shafranov equation, such as Picard, Newton-Raphson and Newton-Krylov, in order to provide a robust and reliable tool, able to handle large-scale problems (e.g. highresolution equilibria). This method has been implemented in the FRIDA code (FRee-boundary Integro-Differential Axisimmetric – https://github.om/matteobonotto/FRIDA), together with a suitable Adaptive Integration Technique (AIT) for the computation of the source term. FRIDA has been successfully tested and validated againstexperimental data from RFX-mod device, and numerical equilibria of an ITER-like device.     

Microstructural basis of contusion expansion in traumatic brain injury: insights from diffusion tensor imaging

Traumatic brain injury (TBI) is often exacerbated by events that lead to secondary brain injury, and represent potentially modifiable causes of mortality and morbidity. Diffusion tensor imaging was used to characterize tissue at-risk in a group of 35 patients scanned at a median of 50 hours after injury. Injury progression was assessed in a subset of 16 patients with two scans. All contusions within the first few days of injury showed a core of restricted diffusion, surrounded by an area of raised apparent diffusion coefficient (ADC). In addition to these two well-defined regions, a thinner rim of reduced ADC was observed surrounding the region of increased ADC in 91% of patients scanned within the first 3 days after injury. In patients who underwent serial imaging, the rim of ADC hypointensity was subsumed into the high ADC region as the contusion enlarged. Overall contusion enlargement tended to be more frequent with early lesions, but its extent was unrelated to the time of initial imaging, initial contusion size, or the presence of hemostatic abnormalities. This rim of hypointensity may characterize a region of microvascular failure resulting in cytotoxic edema, and may represent a ‘traumatic penumbra'' which may be rescued by effective therapy.     

Using a Personal Digital Assistant to Increase Independent Task Completion by Students with Autism Spectrum Disorder

In this study, a personal digital assistant (PDA) with picture, auditory, and video prompts with voice over, was evaluated as a portable self-prompting device for students with autism spectrum disorder (ASD). Using a multiple probe design across three cooking recipes and replicated with three students with ASD, the system was tested for its effectiveness in increasing independent performance across the multiple step tasks. In addition, data were recorded for the number and types of prompts used by the students across time. Results indicate that the students with ASD were able to adjust the prompt levels used on the PDA and to maintain their ability to use the device to independently complete recipes over time.     

Effects of indomethacin on postural hypotension in Parkinsonism.

A study was conducted to evaluate the effect of indomethacin on orthostatic hypotension in Parkinsonism. Twelve elderly patients participated and the drug was given in two-ways--as an intravenous infusion of 50 mg over 30 minutes and by mouth 50 mg thrice daily for six days. Results were assessed by measuring the degree of hypotension on standing, response to the cold pressor test, and forearm blood flow (by strain-gauge plethysmography). Indomethacin significantly reduced the fall in blood pressure on standing (P less than 0:001) and lessened or reversed orthostatic symptoms. Furthermore, there was an enhanced response to the cold pressor test and a reduction in forearm blood flow. These findings suggest that indomethacin has a positive effect on systemic vascular resistance.     

Laser division of the aryepiglottic folds for severe laryngomalacia

Laryngomalacia is an entity of ill-defined etiology. The clinical situation is one of inspiratory stridor present at birth, or within the newborn period. The stridor may increase in severity for the first several months of life and thereafter spontaneously begins to resolve. In the majority of cases the condition resolves spontaneously by approximately two years of age. This report will present the surgical management of severe laryngomalacia in infants using the carbon dioxide laser to surgically divide the aryepiglottic fold with resolution of the laryngomalacia.     

Management of traumatic arterio-venous fistulas,experience in Armed Forces General Hospital,Addis Ababa

In Armed Forces General Hospital from March to December 1999, 53 patients were operated for Arterio-venous fistula. All were males, their age ranging from 19 to 46 years, average 27 years. The diagnosis of arterio-venous fistulas was established clinically. The pathological distribution of the lesions were: 23(43.4%) Arterio-Venous aneurysm; 11(20.75%) Arterio-Venous fistula, 19(35.85%) Arterial false aneurysms. The anatomical location was: 15 femoral, 10 Tibial, 6 poplitial, 6 brachial, 4 Axilláry, 1 ulnar, 7 external carotid and 1 occipital. The types of surgical procedures performed were: 29 (54.72%) excision of the arterio-venous fistula and aneurismal sac with arterial restoration by end to end anastomosis and/or saphenous vein graft, 16(30.19%) by excision of arteriovenous fistula and quadriple ligation of small vessels, 8(15.09%) excision of the false aneurismal sac and lateral repair of the artery (lateral arterioraphy). During the post operative period the patients were followed for three months, and we had the following results based on the clinical outcome criteria; 37(69.81%) excellent, 15(28.3%) good and 1(1.89%) fair.     

A new rapid bedside assay for quantitative testing of D-Dimer (Cardiac D-Dimer) in the diagnostic work-up for deep vein thrombosis

The accuracy of a new bedside, rapid and quantitative D-Dimer assay (Cardiac D-Dimer) was evaluated in outpatients with clinically suspected deep vein thrombosis (DVT); VIDAS test was used as reference method. Eighty consecutive outpatients with suspected DVT of a lower limb were included in the study. Patients were classified as DVT positive or negative according to results of objective test (serial CUS), pretest clinical probability and 3-month follow-up. DVT was diagnosed in 32/80 patients (40%). The performance of the two D-Dimer assays was comparable, as indicated by the areas under the ROC curves (0.89 and 0.88, for Cardiac D-Dimer and VIDAS, respectively) and the coefficient of correlation (r=0.91). The reproducibility of the test was acceptable (from 6.2% to 12.0%). The sensitivity and negative predictive values were 100% for both tests. The specificity (SP) and positive predictive values (PPV) were similar (SP: 50.0% and 52.0%, PPV: 57.1% and 58.2%, for Cardiac D-Dimer and VIDAS, respectively). The Cardiac D-Dimer test proved to be very accurate and produced results fully comparable to those obtained with the VIDAS test. Since the test can be directly performed in the emergency room within a few minutes, it seems to have great clinical potential. The place of this assay in the diagnostic strategy of DVT remains to be determined in prospective management studies.     

Role of RT-PCR tyrosinase detection in the monitoring of patients with advanced metastatic melanoma

In recent studies a new method has been proposed to detect circulating melanoma cells in the peripheral blood of patients, based on the amplification of the mRNA for tyrosinase, an enzyme involved in melanin biosynthesis that is expressed only by melanocytic cells. The sensitivity and clinical relevance of this method are still controversial. In the present study, 596 blood samples from 186 melanoma patients at various clinical tumour stages, together with samples from 25 healthy volunteers, were analysed with the aim of investigating the value of tyrosinase detection in predicting melanoma recurrence. We suggest a possible role for this marker in the monitoring of melanoma patients after the excision of regional lymph node metastases, and provide evidence that tyrosinase is related to the status of disease in advanced metastatic patients. Moreover, chemotherapy administration appeared to influence tyrosinase determination and may explain the discrepancies in the reported percentages of positive samples.     

ENPP1/PC-1 K121Q polymorphism and genetic susceptibility to type 2 diabetes

Genetic susceptibility modulates the impact of obesity on risk for type 2 diabetes. The present study evaluates the role of ENPP1 K121Q polymorphism in prediction of type 2 diabetes in three populations that differ in susceptibility to diabetes and environmental exposure. The three cohorts included 679 nonmigrant South Asians living in Chennai, India (223 with type 2 diabetes); 1,083 migrant South Asians living in Dallas, Texas (121 with type 2 diabetes); and 858 nonmigrant Caucasians living in Dallas, Texas (141 with type 2 diabetes). Patients with type 2 diabetes were included in these cohorts if they had diabetes onset before the age of 60 years. The prevalence of subjects carrying the polymorphic ENPP1 121Q allele was 25% in the nondiabetic group and 34% in the diabetic group of South Asians living in Chennai (P = 0.01). The prevalence in the nondiabetic and diabetic groups were 33 and 45% (P = 0.01) for the South Asians living in Dallas and 26 and 39% (P = 0.003) for the Caucasians. Although further replication studies are necessary to test the validity of the described genotype-phenotype relationship, our study supports the hypothesis that ENPP1 121Q predicts genetic susceptibility to type 2 diabetes in both South Asians and Caucasians.     

Effects of antioxidant supplementation on postprandial oxidative stress and endothelial dysfunction: a single-blind, 15-day clinical trial in patients with untreated type 2 diabetes, subjects with impaired glucose tolerance, and healthy controls

BACKGROUND: Increased generation of reactive oxygen species (ROS) and oxidative stress may be of crucial importance in the pathogenesis of endothelial damage. Furthermore, there is understood to be a relationship between endothelial damage, glycemic control, disorders of lipid metabolism, and coagulative hemostatic disorders. OBJECTIVE: This study investigated within- and between-group changes in various circulating markers of oxidation-reduction balance and endothelial function after a balanced moderate-fat meal with and without antioxidant supplementation in patients with early-stage, untreated type 2 diabetes mellitus; subjects with impaired glucose tolerance (IGT); and healthy controls. METHODS: In this single-blind, controlled clinical study, groups of patients with type 2 diabetes and subjects with IGT were identified and compared with a group of healthy controls. All groups followed a controlled, well-balanced diet for 10 days before and throughout the study. Before and after consumption of a standardized moderate-fat meal, plasma levels of oxidants (malondialdehyde, 4-hydroxynonenal, oxidized low-density lipoprotein), the antioxidant glutathione peroxidase, and markers of endothelial function (NO, endothelin-1, von Willebrand factor [vWF], vascular cell adhesion molecule-1 [VCAM-1]) were determined. These measures were then reassessed after 15 days of standard antioxidant treatment consisting of a thiol-containing antioxidant (N-acetylcysteine 600 g/d), a bound antioxidant (vitamin E 300 g/d), and an aqueous phase antioxidant (vitamin C 250 mg/d). The efficacy of antioxidant treatment in reversing abnormalities in oxidation-reduction balance after a moderate-fat meal was assessed by evaluating changes in plasma levels of ROS on the morning of the 16th day following an overnight fast. Safety was monitored in terms of adverse events, vital signs, physical findings, and laboratory values. RESULTS: The study included 46 patients with type 2 diabetes (23 men, 23 women; mean [SD] age, 41 [3] years; mean body mass index [BMI], 24 [2] kg/m(2)), 46 with IGT (23 men, 23 women; mean age, 39 [3] years; mean BMI, 23 [3] kg/m(2)), and 46 control subjects (23 men, 23 women; mean age, 40 [1] years; mean BMI, 22 [1] kg/m(2)). Before supplementation, all 3 groups had significantly increased levels of oxidants, vWF, and VCAM-1 (all, P < 0.001) and significantly decreased levels of antioxidants and NO (both, P < 0.001) after consumption of a moderate-fat meal. After 15 days of antioxidant treatment, significant improvements in these measures were seen in all groups (P < 0.05). CONCLUSIONS: This study showed changes in oxidation-reduction balance, NO bioavailability, and nonthrombogenic endothelial factors after a moderate-fat meal in patients with type 2 diabetes and those with IGT, but these postprandial changes were reverse in all subjects after 15 days of standard antioxidant supplementation. These findings suggest that the use of anti-oxidants may have decreased oxidative stress in these subjects.