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1.
We investigated the regulation of COX-2 expression and activity by adenosine receptors in rat microglial cells. The selective adenosine A2a-receptor agonist CGS21680 and the non-selective adenosine A1- and A2-receptor agonist 5'-N-ethylcarboxiamidoadenosine (NECA) induced an increase in COX-2 mRNA levels and the synthesis of prostaglandin E2 (PGE2). The adenosine A1-receptor agonist cyclopentyladenosine (CPA) was less potent, and the adenosine A1-receptor-specific agonist N6-2-(-aminophenylo)ethyladenosine (APNEA) showed only marginal effects. Microglia expressed adenosine A1-, A2a-, and A3-, but not A2b-receptor mRNAs, whereas astroglial cells expressed adenosine A2b- but not A2a-receptor mRNA. The adenosine A2a-receptor selective antagonist (E)-8-(3,4-dimethoxystyryl)-1,3-dipropyl-7-methylxanthine (KF17837) inhibited both CGS21680-induced COX-2 expression and PGE2 release. CGS21680-increased PGE2 levels were inhibited by dexamethasone, by the nonsteroidal antiinflammatory drug meloxicam, and by the adenylyl cyclase inhibitor 9-(tetrahydro-2-furanyl)-9H-purine-6-amine (SQ22536). CGS21680 and NECA both increased intracellular cAMP levels in microglial cells. Dibutyryl cAMP as well as forskolin induced the release of PGE2. The results strongly suggest that adenosine A2a-receptor-induced intracellular signaling events cause an up-regulation of the COX-2 gene and the release of PGE2. Apparently, the cAMP second messenger system plays a crucial role in COX-2 gene regulation in rat microglial cells. The results are discussed with respect to neurodegenerative disorders of the CNS such as Alzheimer's disease, in which activated microglia are critically involved and COX inhibitors may be of therapeutic benefit.  相似文献   

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We describe a form of hereditary motor and sensory neuropathy (HMSN) affecting four siblings in an Italian family of Gypsy ethnic origin with both clinical and pathological findings very reminiscent of the HMSN Lom type (HMSNL), recently described in a group of Bulgarian Gypsies. Genetic analysis demonstrated linkage to chromosome 8q24 and conserved haplotypes in the HMSNL region, thus confirming that this is the first Gypsy family outside the Balkans suffering from the same disorder.  相似文献   

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The demyelinating type of hereditary motor and sensory neuropathy (HMSN I) is characterized by progressive weakness and atrophy of leg muscles. Six patients (age, 25-79 yr) belonging to three generations had calf hypertrophy (6 of 6), foot drop or difficulty with heel walking (4 of 6), pes cavus (3 of 6), absent or depressed tendon jerks in the lower limbs (4 of 6), and mild distal sensory loss (3 of 6). No other family member had leg atrophy. Motor conduction velocities ranged from 20 to 40 m/sec. Sural nerve biopsy showed loss of large myelinated fibers, numerous onion bulbs, and segmental demyelination and remyelination. Computed tomographic scans of leg muscles and histological and morphometric findings in gastrocnemius revealed true muscular hypertrophy. Southern blot and fluorescence in situ hybridization documented the duplication of the entire 17p11.2 segment associated with classical HMSN IA. The pathogenesis of muscle hypertrophy in our cases is unclear. Chronic leg muscle weakness and long-standing partial denervation might cause calf enlargement by a combination of compensatory "work-induced" and "stretch-induced" fiber hypertrophy. Alternatively, that all the affected family members presented calf hypertrophy might suggest the action of a genetic factor associated with the duplication at 17p11.2.  相似文献   

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Clinical, biological and electrophysiological features from a cohort of 39 multifocal motor neuropathies with conduction blocks (NMM with CB) have been studied. There were 29 males and 10 females with an average of 47.3. At the first evaluation, the mean duration of the symptoms was of 8 years with extremes between 1 and 28. Pain and paresthesias were present in respectively 10 and 18 p. 100 of the patients. Fasciculations and cramps were observed in more than 2/3 of the cases. Three patients had tremor at rest. Upper limb muscular weakness was the predominant initial symptom (84.6 p. 100). The weakness always affected distal and unilateral muscles. Radial and cubital nerve distribution are mainly affected and in half of the cases an unilateral motor deficit in the lower limb was associated. Muscle atrophy was frequent (74 p. 100) and rapidly developed in the first 2 years. Reflexes were decreased or absent in 64 p. 100. In 78 p. 100 of cases, biological study showed normal serum immunoelectrophoresis and CSF. IgM anti-GM1 antibodies were found in 24/36 patients. Very high titres were found in 5 cases. All patients had CB in upper limbs. The preferential localizations of the CB were equally at the median and ulnar nerves. Only 7 patients had CB localized to the lower limbs. In many cases, marked reduction of the motor amplitude prevented the detection of CB, marked reduction of the motor amplitude prevented the detection of CB. Moderate fibrillation potentials were found in 28 p. 100 of patients. Giant muscular unit potentials were frequent (21/39). F-waves in nerve with CB were always abnormal with marked increased latencies. Late responses sometimes seemed to be repeater F-waves. Axon reflexes were detected in 5 cases. The late responses abnormalities could precede the block. Clinical, biological and electrophysiological described arguments could may distinguish NMM with CB from motor neuron disease and relate them to the group of chronic demyelinating neuropathies.  相似文献   

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To determine the effect of RGP contact lens solution on corneal epithelial wound healing, the following solutions including Soaclens, Contopharma GPHCL-S, Boston condition, Bausch & Lomb condition and Duracare were applied on corneal epithelial wounds of enucleated pig eyes to evaluate possible cytotoxicity of RGP solutions. The wounds, created by excimer laser, were 1.5mm in diameter with 70 microns in depth. The eyeballs were maintained in an incubator using a perfusion system. After twenty-four hours, a score from 3 to 0 was given depending on the size of defect from absence of healing to completely healing. The average scores of the epithelial defect in each group are: Soaclens: 0.38 +/- 0.74; GPHCL-S: 0.63 +/- 0.52; Boston condition: 0.38 +/- 0.52; Bausch & Lomb condition: 0.25 +/- 0.46 and Duracare: 2.38 +/- 0.52. Most of the epithelial wounds healed with one exception, the eyeballs which received Duracare still had large defects. The difference of scores between Duracare and other groups are statistically significant. Duracare, which contains benzalkonium chloride, may be responsible for retarded wound healing.  相似文献   

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The molecular, genetic and enzymological abnormalities in Gaucher's disease have been delineated during the past decade. Although our understanding of the primary predisposition to the Gaucher's disease phenotypes has improved, the relationships remain poorly understood between the mutant alleles, the resultant enzyme variants, the saposin C (activator protein) locus and phenotypes. Of the more than 100-disease associated alleles, about 8 to 10 have significant frequencies in various ethnic and demographic groups. The N370S(1226G) allele is very frequent in Caucasian populations, but absent in Asian groups. In the Ashkenazi Jewish population, the N370S homozygosity predisposes to Gaucher's disease, but over 50% of such patients escape medical detection because of their mild to absent involvement, i.e. N370S may be a prediposing polymorphic variant. Clarification of genotype/phenotype relationships and the identification of modifier loci that impact on Gaucher's disease phenotypes remain a critical area for research. Greater understanding of these issues will facilitate genetic counselling and appropriate interventive therapy to prevent the morbid long-term manifestations of Gaucher's disease.  相似文献   

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Hereditary spherocytosis is a common and very heterogeneous hemolytic anemia caused by defects of the red cell membrane proteins. In recent years, major advances in our understanding of the red cell membrane skeleton and a better characterization of its individual components have allowed a brighter insight into the pathogenesis of the disease. In this article, we present an overview of the erythrocyte skeleton and its individual constituents. We also review the clinical aspects of the disease and describe the currently known molecular defects involving the membrane proteins which have been shown to play an essential role in the underlying mechanism of hereditary spherocytosis. Finally we examine several models that have been proposed in an attempt to clarify the mechanism leading from the initial molecular insult to the clinical phenotype.  相似文献   

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Twenty-seven patients (15 males, 12 females, age range: 16-66 years) were admitted for malformative syringomyelia diagnosed on MRI with measures of syrinx extending and transverse diameter. Posterior tibial somatosensory evoked potentials (PT SEP), median (M SEP), trigeminal (V3 SEP), brain stem auditory evoked potentials (BEAP), cortical and cervical motor evoked potentials (MEP) were correlated with clinical and radiological findings. SEP abnormalities were not correlated with the duration of symptoms. PT SEP proved to be more sensitive than M SEP. MEP abnormalities were very frequent (87% of the cases), even without clinical motor deficits. Trigeminal SEP were more sensitive than BEAP which were not related to the presence of associated cranio-vertebral abnormalities. We found no significative relationship between clinical and radiological results. Moreover, there was a positive relationship between electrophysiological and radiological results: abnormal trigeminal SEP were detected in 85% of the patients with high cervical syringomyelia. In all cases, trigeminal SEP and MEP should be done in association with M and PT SEP as both of them detect subclinical evidence of spinal cord dysfunction in syringomyelia.  相似文献   

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Structural properties of an equilibrium intermediate formed upon urea-induced unfolding of more ordered staphylococcal nuclease A-forms (A2 and A3) are studied. The effect of association on the structural properties and conformational stability of this unfolding intermediate is also considered. A close structural similarity (including tendency for association) is shown between this intermediate and the least ordered A1-form, induced in the acid-unfolded nuclease by moderate sulfate or chloride concentrations.  相似文献   

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AIM: To report on the clinical and molecular aspects of Gaucher disease in New Zealand. METHODS: Patients known to have Gaucher disease were contacted and clinical information was recorded by questionnaire. Blood samples from affected individuals and their families provided DNA material for mutation analysis of disease causing alleles. Patients were assayed for beta-glucocerebrosidase, the enzyme deficiency which causes Gaucher disease. RESULTS: Twelve of 14 patients and 10 carriers were confirmed by DNA analysis. One asymptomatic individual was diagnosed. Four known mutations (N370S, 1444p, R463c and RecNcIl) and one unknown mutation were found from the 34 disease producing alleles that were identified. Of these, the L444P and N370S alleles were the most common. Most patients exhibited a clinical disorder typical of type 1 Gaucher disease. Two recent patients with severe neuropathic Gaucher disease had died in childhood. All patients showed a deficiency in beta-glucocerebrosidase. CONCLUSION: Gaucher disease in New Zealand is represented in a small number of non Jewish individuals with varying severity. Identifiable mutations and clinical symptoms aid in expanding the Australasian picture of this well studied disease. Enzyme replacement therapy for these patients has recently commenced in New Zealand.  相似文献   

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The study included 22 patients with poststroke epilepsy (group 1) and 30 patients with stroke without epilepsy (group 2). A bilateral decrease of the time of central conduction (TCC) through pyramidal path (both on the paretic and intact side) was revealed in group 1. This was not observed in patients of group 2 with similar gravity of motor disorders (p < 0.01). Tendency to TCC decrease was also observed in patients without epileptic disorders by day 5-6 after ischemic stroke. However, TCC values were increased in such patients by day 10-14. Low indices persisted for a long time in patients with poststroke. There was also an increase of delta index of facilitation (the difference between TCC in rest and in muscle effort). It was also found that motor disorders in the group of patients with poststroke epilepsy were characterised by higher muscular tone than in poststroke patients with the same degree of the paresis.  相似文献   

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As shown in long term follow-up studies of Total Knee Arthroplasty (TKA), the femoropatellar joint is an important problem. We report our experience over the past seven years not having resurfaced the patella at the primary TKA at all. Between 1990 and 1997 more than 700 consecutive TKA with the De Puy New Jersey LCS prosthesis were performed. A standardised lateral approach with osteotomy of the tibial tuberosity was used. The patella was redressed, either denervated or left untouched. In no case a primary patellar resurfacing was performed. X-rays of the patello-femoral joint showed a remodelling of the patella over the years, nicely matching the condylar design of the femoral prosthesis. Using a blood-supply-preserving approach and a biomechanically adequate implant, TKA without patellar replacement gives excellent long-term results.  相似文献   

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Discusses evidence concerning genetic influences on developmental dyslexia, a disorder characterized by difficulty in learning to read despite adequate opportunity and intelligence. Research on familial incidence, concordance in twins, the influence of parental age at the child's birth, and the subtyping of dyslexics is summarized. It is concluded that there is strong evidence for the heritability of a subtype based on verbal/language deficiency, perhaps reflecting reversed cerebral asymmetry, for which a genetic marker has been found. It is uncertain whether this subtype is caused by left hemispheric impairment or immaturity. There is somewhat weaker evidence for the heritability of a subtype based on visual/spatial deficiencies and a mixed subtype. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Among 660 cases of thyroid pathology diagnosed by the 2nd Institute of Clinical Surgery, Policlinico San Matteo, IRCCS, Pavia, during the period 1984 to 1993, 34 cases of cervical-mediastinal goiter were observed with an incidence of 5%. After a careful analysis of the main contributions to the study of cervical-mediastinal goiters, paying special attention to their classification, pathogenesis, methods of growth, and unique symptomatic manifestations, the authors focus on current radiological and instrumental studies, which are widely regarded as being useful for the diagnosis of the site and nature of this disease. They review the routes for aggressive surgery and appropriate techniques for the exeresis of the mediastinal mass. Having empasised the absolute indication for surgery the authors recommend quasi-total or total thyroidectomy as the elective form of surgery.  相似文献   

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