Clinical Neuroscience

[Aspirin and clopidogrel resistance: possible mechanisms and clinical relevance. Part II: Potential causes and laboratory tests]

VADÁSZ Dávid1, SZTRIHA K. László1, SAS Katalin1, VÉCSEI László1

JANUARY 25, 2013

Clinical Neuroscience - 2013;66(01-02)

[Recent meta-analyses have indicated that patients with vascular disease demonstrated by laboratory tests to be aspirin or clopidogrel-resistant are at an increased risk of major vascular events. The suggested mechanisms of aspirin resistance include genetic polymorphism, alternative pathways of platelet activation, aspirin-insensitive thromboxane biosynthesis, drug interactions, or a low aspirin dose. Clopidogrel resistance is likely to develop as a result of a decreased bioavailability of the active metabolite, due to genetic variation or concomitant drug treatment. Additional work is required to improve and validate laboratory tests of platelet function, so that they may become useful tools for selection of the most appropriate antiplatelet therapy for an individual patient. Improvements in antiplatelet treatment strategies in the future should lead to a reduction in premature vascular events.]

AFFILIATIONS

  1. University of Szeged, Albert Szent-Györgyi Clinical Center, Faculty of Medicine, Neurology Department, Szeged, Hungary

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Clinical Neuroscience

[The significance of high-resolution ultrasonography in the diagnosis of peripheral nerve disorders]

SCHEIDL Erika, JOSEF Böhm, FARBAKY Zsófia, DEBRECZENI Róbert, BERECZKI Dániel, ARÁNYI Zsuzsanna

[High resolution ultrasonography is an emerging technique for the investigation of peripheral nerves and is increasingly used worldwide in the diagnosis of peripheral nerve disorders, however, until now it is not widespread in Hungary. According to the literature this method is especially useful in entrapment neuropathies, traumatic peripheral nerve injuries, tumors of the peripheral nerves and sonographically guided interventions. Ultrasonography allows precise morphological analysis and quantitative measurements of the nerves providing useful complementary information to electrodiagnostic data. In entrapment neuropathies ultrasound shows nerve swelling mainly proximal to the sites of compression and a focal change of echotexture. On longitudinal scan, an abrupt caliber change and spindle-like swelling of the compressed nerve segment can be seen. Evaluation of the anatomical background and visualisation of the postoperative and posttraumatic changes provide useful information for planning of the therapy. Ultrasound may be of significant help in localizing the pathological nerve segment when it is at an electrophysiologically inaccessible site or when substantial secondary axonal loss precludes precise electrophysiological localization and it might even show pathological changes when nerve conduction studies are normal. Contrary to electrophysiological investigation ultrasonography might discover neurotmesis in the akute phase of traumatic nerve injuries indicating the necessity of surgical intervention. We provide a summary of the main indications and further application areas of this method.]

Clinical Neuroscience

[Editorial message]

KINCSES Zsigmond Tamás

Clinical Neuroscience

[Blood lipid peroxidation, antioxidant enzyme activities and hemorheological changes in autistic children]

LÁSZLÓ Aranka, NOVÁK Zoltán, SZÕLLÕSI-VARGA Ilona, HAI Quai Du, VETRÓ Ágnes, KOVÁCS Attila

[Objectives - Early infantile autism is a severe form of childhood psychiatric disease with characteristic symptoms. Hyperserotoninaemia in 43.5%, lactic acidosis 43% and hyperpyruvataemia in 30% were biochemically demonstrated in autistic children. Our earlier results led to the postulation that a disequilibrium in the blood redox is involved in infantile autism; the oxidative loading and the antioxidant defending enzyme system were investigated together with the hemorheological parameters in infantile autism. Methods - Malonyl-dialdehyde (MDA) endproduct of lipid peroxidation and activities of the antioxidant enzymes: superoxide dismutase (SOD), catalase (C-ase), glutathione peroxidase (GP-ase) and reduced glutathione (GSH) were biochemically determined from plasma and red blood cells. Patients - The antioxidant specificities were investigated in plasma and red blood cell haemolysate from 25 infantile autistic children. Results - Significantly increased superoxide dismutase (SOD) (2.89 vs. 1.32 U/mg protein, p<0.01) and decreased glutathione peroxidase (0.620 vs. 0.910 U/mg protein, p<0.01) levels as well as catalase (0.463 vs. 4.948 BU/mg protein, p<0.001) activities were detected; while the plasma and erythrocyte lipid peroxidation and the reduced glutathione (GSH) levels did not change. The results of the investigated prooxidant and the antioxidant status provide evidence that there exists an oxidative stress in children with infantile autism. While investigating the hemorheological parameters of 25 infantile autistic patients, some characteristic pathological parameters were detected: the initial filtration rate (Fi) (0.72 vs. 0.75 p<0,01) and the clogging rate (CR) (1.926 vs. 2.912, p<0.01) values of red blood cells (RBC) decreased while the mean transit time (Tc) (8.93 vs. 7.39, p<0.001) increased suggesting reduced RBC deformability.]

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[Objective - In neurology the objective evaluation of improvement of paresis on every-day practice. The aim of this study was to develope and test a small 3-d acceleration measuring device and validate its usefulness. Patients and methods - We collected data from 17 mild and medium severity hemiparetic, bedridden acute ischaemic and hemorrhagic stroke patients and compared with data of 22 control subjects. The devices were attached to the paretic and non-paretic extremities and any movements (m/s2) and movement-durations were registered (24h). The data of movement-monitors were compared also with the changes of National Institute of Health Stroke Scale and European Stroke Scale. The electromiograph-sensor of polysomnograph has been used for validation. Results - Mild differences could be found in the use of dominant and non-dominant upper extremities of control persons. The control persons used their upper extremities more frequently than the stroke patients. Our data showed significant correlation with National Institute of Health Stroke Scale. Higher values on the scores were accompanied with less intensive use of extremities. We found a correlation between the consiousness level of patients and their activity of upper extremities. If the patients had severe consiousness disturbances they used significantly less their upper extremities. Conclusion - Our device sensitively detected the movement-differences between paretic and non-paretic extremities and can be used for quantitative evaluation of patient's neurological and consciousness status.]

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[Background and purpose - Previous neuropsychological studies produced inconsistent results with tasks tapping short-term verbal and visual-spatial memory and executive functions in obsessive compulsive disorder (OCD). The aim of this study was to investigate the presence of deficits in these cognitive domains. A further goal was to describe the distribution of patients in different impairment ranges for all functions, and clarify the relationship between symptom severity and cognitive impairments. Methods - Thirty patients with OCD (DSM-IV) and 30 healthy volunteers were compared using well-known neuropsychological tasks. We assessed short-term verbal memory with the Digit Span Forward and Digit Span Backward Tasks, short-term visual-spatial memory with the Corsi Block Tapping Task, while we measured the level of executive functions with the StroopTask and the Wisconsin Card Sorting Test (WCST). Results - Compared with a matched healthy control group, the performance of OCD patients was in the impaired range only in the two executive tasks. We find a significant positive correlations between the Y-BOCS (Yale-Brown Obsessive Compulsive Scale) total scores and the number of perseverative responses (r(28)=0.409, p<0.05) and perseverative errors (r(28)=0.385, p<0.05) in the WCST. Conclusion - Our results gave evidence that executive functions are impaired while short-term memory is intact in OCD. This is in line with neuropsychological model of OCD that the deficit of cognitive and behavioral inhibition are responsible for the main cognitive findings of this disorder, most prevalently the deficit in set shifting and prepotent response inhibition.]

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