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11.
Jean-Fran ois Marini Fran oise Pons Jocelyne Leger Nathalie Loffreda Monique Anoal Martine Chevallay Michel Fardeau Jean J. Leger 《Neuromuscular disorders : NMD》1991,1(6):397-409
The expression of MHC isoforms in the skeletal muscles of nine patients with Duchenne muscular dystrophy (DMD) (from 2.5 to 15 yr of age) and three DMD carriers was studied using different specific anti-MHC MAbs. We also analyzed muscle fiber size and fiber reactivity with acridine orange and/or with a surface antigen marker. One-quarter of all fibers of DMD patients, or less with age, were of normal size and contained only adult slow MHC. Half of the muscle fibers contained adult and developmental MHCs. Only half of these fibers were representative of an active regenerative process. MHC co-expression also altered the proportion of normal fast or slow fibers. Adult fast MHCs were expressed as unique MHC only in small and very small fibers in the oldest DMD patients. In DMD carrier muscles, the greatest alterations in MHC expression were observed in patients with the most reduced dystrophin expression. However, MHC changes in dystrophin-positive fibers were similar to those observed in dystrophin-free fibers. In conclusion, disruptions or delays in the switching of all genes coding for adult fast and slow MHC and developmental MHC coincided with dystrophin deletion and with perturbations in its expression. 相似文献
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G. Lallement Didier Clarençon Catherine Masqueliez Dominique Baubichon Monique Galonnier Marie-France Burckhart Michel Peoc’h Jean Claude Mestries 《Archives of toxicology》1997,72(2):84-92
Organophosphorus nerve agents are still in use today in warfare and as terrorism compounds. Classical emergency treatment
of organophosphate poisoning includes the combined administration of a cholinesterase reactivator (an oxime), a muscarinic
cholinergic receptor antagonist (atropine) and a benzodiazepine anticonvulsant (diazepam). However, recent experiments with
primates have demonstrated that such treatment, even when administered immediately after organophosphate exposure, does not
rapidly restore normal electroencephalographic (EEG) activity and fails to totally prevent neuronal brain damage. The objective
of this study was to evaluate, in a realistic setting, the therapeutic benefit of administration of GK-11 (gacyclidine), an
antiglutamatergic compound, as a complement to the available emergency therapy against organophosphate poisoning. GK-11 was
injected at a dose of 0.1 mg/kg (i.v) after a 45-min latency period to heavily intoxicated (8 LD50) primates. Just after intoxication, man-equivalent doses of one autoinjector containing atropine/pralidoxime/diazepam were
administered. The effects of GK-11 were examined on survival, EEG activity, signs of toxicity, recovery after challenge and
central nervous system histology. The present data demonstrate that treatment with GK-11 prevents the mortality observed after
early administration of classical emergency medication alone. EEG recordings and clinical observations also revealed that
GK-11 prevented soman-induced seizures and motor convulsions. EEG analysis within the classical frequency bands (beta, theta,
alpha, delta) demonstrated that central activity was totally restored to normal after GK-11 treatment, but remained profoundly
altered in animals receiving atropine/pralidoxime/diazepam alone. GK-11 also markedly accelerated clinical recovery of soman-challenged
primates. Lastly, this drug totally prevented the neuropathology observed 3 weeks after soman exposure in animals treated
with classical emergency treatment alone. GK-11 represents a promising adjuvant therapy to the currently available emergency
polymedication to ensure optimal management of organophosphate poisoning in man. This drug is presently being evaluated in
a human clinical trial for a different neuroprotective indication.
Received: 16 June 1997 / Accepted: 23 September 1997 相似文献
15.
Evidence that [3H]-alpha,beta-methylene ATP may label an endothelial-derived cell line 5'-nucleotidase with high affinity. 总被引:1,自引:1,他引:0 下载免费PDF全文
A. D. Michel N. M. Chau T. P. Fan E. E. Frost P. P. Humphrey 《British journal of pharmacology》1995,115(5):767-774
1. In membranes prepared from a permanent cell line of endothelial origin (WEC cells), [3H]-alpha, beta-methylene ATP ([3H]-alpha, beta-meATP) labelled high (pKd = 9.5; Bmax = 3.75 pmol mg-1 protein) and low (pKd = 7.2; Bmax = 23.3 pmol mg-1 protein) affinity binding sites. The high affinity [3H]-alpha, beta-meATP binding sites in the WEC cell membranes could be selectively labelled with a low concentration of the radioligand (1 nM). In competition studies performed at a radioligand concentration of 1 nM, 88.6% of the sites possessed high affinity (pIC50 = 8.26) for alpha, beta-meATP. 2. The high affinity [3H]-alpha, beta-meATP binding sites appeared heterogeneous since in competition studies a number of nucleotide analogues (alpha, beta-meADP, ATP, ADP, AMP, GTP, GppNHp, GMP) and adenosine identified two populations of the sites labelled by 1 nM [3H]-alpha, beta-meATP. The proportion of sites with high affinity for these compounds was found to vary between 42 and 69%. 3. Approximately 60-69% of the binding sites labelled with 1 nM [3H]-alpha, beta-meATP possessed high affinity for alpha, beta-meADP (pIC50 = 8.87), AMP (pIC50 = 7.12), GMP (pIC50 = 7.34), UTP (pIC50 = 6.12), GTP (pIC50 = 7.59), GppNHp (pIC50 = 7.35) and adenosine (pIC50 = 5.45).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
16.
Catherine Beckers Clio Ribbens Béatrice André Stefaan Marcelis Olivier Kaye Luc Mathy Marie-Jo?lle Kaiser Roland Hustinx Jacqueline Foidart Michel G Malaise 《Journal of nuclear medicine》2004,45(6):956-964
The aim of this study was to assess synovitis by (18)F-FDG PET in an individual joint analysis and in a global analysis of rheumatoid arthritis (RA) disease activity and to compare (18)F-FDG PET parameters with clinical, biologic, and sonographic (US) rheumatoid parameters. METHODS: Three hundred fifty-six joints were assessed in 21 patients with active RA: the knees in all subjects and either wrists as well as metacarpophalangeal and proximal interphalangeal joints in 13 patients, or ankles and the first metatarsophalangeal joints in the remaining 8 patients. PET analysis consisted of a visual identification of (18)F-FDG uptake in the synovium and measurements of standardized uptake values (SUVs). Independent assessors performed the clinical and US examinations. RESULTS: PET positivity was found in 63% of joints, whereas 75%, 79%, and 56% were positive for swelling, tenderness, and US analysis, respectively. Both the rate of PET-positive joints and the SUV increased with the number of positive parameters present (swelling, tenderness, US positivity) and with the synovial thickness. The mean SUV was significantly higher in joints where a power Doppler signal was found. In a global PET analysis, the number of PET-positive joints and the cumulative SUV were significantly correlated with the swollen and tender joint counts, the patient and physician global assessments, the erythrocyte sedimentation rate and C-reactive protein serum levels, the disease activity score and the simplified disease activity index, the number of US-positive joints, and the cumulative synovial thickness. CONCLUSION: (18)F-FDG PET is a unique imaging technique that can assess the metabolic activity of synovitis and measure the disease activity in RA. 相似文献
17.
Martine Hascoët Michel Bourin Jacques Bradwejn 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(6):825-840
1. The mechanism of action of drugs might change according to the test used. Several noradrenergic drugs were tested in order to understand their implication in the mobility tests.
2. It was found that clonidine, an Alpha 2 agonist, acted differently according to the tast used. It provoked sedation in spontaneous activity test, and anti-immobility effects in the other tests.
3. Tall suspension test is able to show the double acting of clonidine.
4. Idazoxan might act either as an alpha 2 antagonist or as partial alpha 2 agonist. TST shown the unexpected partial alpha agonist effect of the molecule.
5. Forced swimming test is more specific for predicting antidepressant activity than tail suspension test which is close to a spontaneous activity model. 相似文献
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Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献