Clinical Neuroscience

[GENETIC BACKGROUND OF HUMAN PRION DISEASES]

KOVÁCS Gábor Géza

NOVEMBER 30, 2007

Clinical Neuroscience - 2007;60(11-12)

[acquired. The human prion protein gene (PRNP) is located to chromosome 20 (20p12-ter). Mutations and polymorphisms in the PRNP are associated with prion disease. Genetic prion diseases are inherited in an autosomal dominant trait, examination of the penetrance is restricted to mutation E200K (59-89%). Mutations can be substitutions or insertions. Genetic prion diseases are classified according to the clinicopathological phenotype and comprise genetic Creutzfeldt-Jakob disease, Gerstmann-Sträussler-Scheinker disease and fatal familial insomnia. Base pair insertions may resemble Creutzfeldt-Jakob disease or Gerstmann-Sträussler-Scheinker disease phenotypes, however, their unique clinicopathological presentations are also emphasized. Among the polymorphisms of the PRNP, the one at codon 129 is the most important, where methionine or valine may be encoded. This polymorphism is known to influence the phenotype of disease forms. Molecular classification of sporadic Creutzfeldt-Jakob disease also depends on the codon 129 polymorphisms in addition to the Western blot pattern of the protease resistant prion protein. According to this at least six well characterised forms of sporadic Creutzfeldt-Jakob disease are known. Influence of other genes were also investigated. Contrasting results are reported regarding the role of apolipoprotein E allele ε4, but presence of allele ε2 seems to influence the prognosis. Polymorphisms in the doppel gene or ADAM10 could not be clearly associated with Creutzfeldt-Jakob disease. Polymorphisms in the upstream and intronic regulatory region of the PRNP gene may be a risk factor for Creutzfeldt-Jakob disease. The PRNP codon 129 polymorphism was examined in non-prion diseases. Some studies suggest that this polymorphism may have influence on the cognitive decline and early onset Alzheimer’s disease.]

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[CATHODAL TRANSCRANIAL DIRECT CURRENT STIMULATION OVER THE PARIETAL CORTEX MODIFIES FACIAL GENDER ADAPTATION]

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[Objective - The standard surgical procedures used in degenerative thoracic and lumbar spinal canal stenosis allows decompression of the neural structures by unroofing the spinal canal, often resulted in destruction or insufficiency of facet joints, sacrifice the interspinosus/supraspinosus ligament complexes and stripping of the paraspinal muscles altering an already pathologic biomechanical milieu causing segmental instability. Various less invasive techniques exists to save the integrity and prevent the instability of the spine and allow decompression of neural structures located in the spinal canal. The authors discusses the experiences with technique of unilateral laminotomy for bilateral decompression. Methods - The unilateral laminotomy for bilateral decompression technique was performed at 60 levels in 51 patients to decompress the symptomatic degenerative stenosis of the thoracic and lumbar spinal canal. The inclusion criteria were used as follows: symptoms of neurogenic claudication and/or radiculopathy, myelopathy, neuroimaging evidence of degenerative stenosis and absence of instability. Symptoms were considered refractory to nonsurgical conservative management or myelopathy was detected. Results - The distribution of mostly affected segments were the L 4-5 (45%) and L3-4 (28.4%). Neurogenic claudication and walking distance improved during the follow up period in all patients. Seven patients (13.73%) reported excellent, 32 (62.74%) good, 12 (23.53%) fair outcome and no patient a poor overall outcome. The low back pain was the major residual postoperative complaint. 25 (49%) patients were very satisfied with their outcome, 23 (45.1%) were fairly satisfied, 2 (3.9%) were not very satisfied and 1 (2%) patients was dissatisfied. Conclusion - The unilateral laminotomy for bilateral microdecompression technique minimizes resection of and injury to tissues not directly involved in the pathologic process, while affording a safe and through decompression of neural structures located in a degeneratively stenotic spinal canal.]

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Clinical Neuroscience

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[OUR EXPERIENCES WITH ANTERIOR CERVICAL CAGES AND SPACER]

SZABÓ József, LAPIS István, MARIK László, KONDACS András, RUSZNYÁK Csaba

[Objectives - Between 2001 and 2005 86 patients were treated for cervical disc herniations and spondylosis at our department. Stabilization was performed with different cervical cages or spacer after discectomy and decompression. The aim of the study was to examine the changes of the patients’ pain, quality of life and work ability, fusion rate, the intervertebral disc height, changes of under and upper segments and finally curvature of cervical spine. Patients and methods - Patients were followed by the authors, clinical examination, lateral and antero-posterior radiographic examinations were performed. They were asked to fill in a questionnaire, concerning their pre- and postoperative pain, quality of life and work ability. The patients’ pain was graded using a 10-point analog scale (VAS) and with a simplified, McGill-Melzak analog scale. The quality of life was measured with a 10-graduated analog scale as well. Results - More than 77% of our patients appeared at follow up examination. The fusion rate was 89.3%, operated spaces were held in 61%. In the upper segment of operated space 7%, and in the under-segment 14% were found increasingly degenerated. The curvature of cervical spine of the patients’ were 64.51% lordotic, 27.42% straight and 8.07% kyphotic. On average the patients’ pain changed on VAS from 8.179 to 5.015; on McGill-Melzak scale from 3.89 to 2.80; quality of life changed from 8.045 to 5.463. Conclusion - By the advantage of using cages, the operative approach has become smaller than before, consequently the operative pain has become less too. In addition operation time and hospital stay were significantly shorter (p<0.005) than using traditional operation approach. The majority of the patients, pain was decreased, quality of life got better. Despite this fact only 3 patients continue their original work and 5 patients do easier work. The majority of our patients were disabled before the operation, but from that time many of them became disabled, in some cases the grade of disability increased. There can be some reasons for it: the majority of the patients have other diseases for example: lumbar spondylosis and disc herniation, hypertension, diabetes, asthma and depression. There is just a few possibility of work for the disabled people. To conclude, with some of the patients, their disability means “the way out” from unemployment. These facts do not decrease the importance and usefulness of this method. Our results with this type of operation are very similar to the international statistics. This method seems to be applicable and useful.]

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