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991.
STUDY DESIGN: Clinical evaluation of the Parastep method, a six-channel transcutaneous functional electrical stimulation device, in spinal cord-injured patients. OBJECTIVES: To investigate the motor performances of this new technique regarding energy expenditure and to evaluate its advantages and limitations, especially in social activities involving ambulation. METHODS: This study was conducted in 15 thoracic spine-injured patients. The lesion was complete except in two patients. The gait ability and the functional use were judged clinically. Energy cost was evaluated from heart rate, peak oxygen uptake, and lactatemia. RESULTS: Thirteen patients completed the training (mean: 20 sessions) and achieved independent ambulation with a walker. The mean walking distance, without rest, was 52.8 +/- 69 m, and the mean speed was 0.15 +/- 0.14 m/sec. One patient with incomplete lesion, who had been nonambulatory for 8 months after the injury, became able to walk without functional electrical stimulation after five sessions. The follow-up was 40 +/- 11 months. Five patients pursued using functional electrical stimulation-assisted gait as a means of physical exercise but not for ambulation in social activities. The patients experienced marked psychological benefits, with positive changes in their way of life. In three subjects, a comparison of physiologic responses to exercise between a progressive arm ergometer test and a walking test with the Parastep (Sigmedics, Inc., Northfield, IL) at a speed of 0.1 m/sec was performed, showing that the heart rate, the peak oxygen uptake, and lactatemia during gait were close to those obtained at the end of the maximal test on the ergometer. CONCLUSIONS: In spite of its ease of operation and good cosmetic acceptance, the Parastep approach has very limited applications for mobility in daily life, because of its modest performance associated with high metabolic cost and cardiovascular strain. However, it can be proposed as a resource to keep physical and psychological fitness in patients with spinal cord injury. 相似文献
992.
993.
Neurodevelopmental disorders in males related to the gene causing Rett syndrome in females (MECP2). 总被引:2,自引:0,他引:2
Ute Moog Eric E J Smeets Kees E P van Roozendaal Sam Schoenmakers Jos Herbergs Anneke M J Schoonbrood-Lenssen Connie T R M Schrander-Stumpel 《European journal of paediatric neurology》2003,7(1):5-12
Mutations in the MECP2 (methyl-CpG-binding protein 2) gene are known to cause Rett syndrome, a well-known and clinically defined neurodevelopmental disorder. Rett syndrome occurs almost exclusively in females and for a long time was thought to be an X-linked dominant condition lethal in hemizygous males. Since the discovery of the MECP2 gene as the cause of Rett syndrome in 1999, MECP2 mutations have, however, also been reported in males. These males phenotypically have classical Rett syndrome when the mutation arises as somatic mosaicism or when they have an extra X chromosome. In all other cases, males with MECP2 mutations show diverse phenotypes different from classical Rett syndrome. The spectrum ranges from severe congenital encephalopathy, mental retardation with various neurological symptoms, occasionally in association with psychiatric illness, to mild mental retardation only. We present a 21-year-old male with severe mental retardation, spastic tetraplegia, dystonia, apraxia and neurogenic scoliosis. A history of early hypotonia evolving into severe spasticity, slowing of head growth, breathing irregularities and good visual interactive behaviour were highly suggestive of Rett syndrome. He has a de novo missense mutation in exon 3 of the MECP2 gene (P225L). The clinical spectrum and molecular findings in males with MECP2 mutations are reviewed. 相似文献
994.
995.
996.
Silke Kauferstein Isabelle Huys Hung Lamthanh Reto St?cklin Filipina Sotto André Menez Jan Tytgat Dietrich Mebs 《Toxicon》2003,42(1):43-52
Toxins from cone snail (Conus species) venoms are multiple disulfide bonded peptides. Based on their pharmacological target (ion channels, receptors) and their disulfide pattern, they have been classified into several toxin families and superfamilies. Here, we report a new conotoxin, which is the first member of a structurally new superfamily of Conus peptides and the first conotoxin affecting vertebrate K+ channels. The new toxin, designated conotoxin ViTx, has been isolated from the venom of Conus virgo and comprises a single chain of 35 amino acids cross-linked by four disulfide bridges. Its amino acid sequence (SRCFPPGIYCTSYLPCCWGICCSTCRNVCHLRIGK) was partially determined by Edman degradation and deduced from the nucleotide sequence of the toxin cDNA. Nucleic acid sequencing also revealed a prepropeptide comprising 67 amino acid residues and demonstrated a posttranslational modification of the protein by releasing a six-residue peptide from the C-terminal. Voltage clamp studies on various ion channels indicated that the toxin inhibits the vertebrate K+ channels Kv1.1 and Kv1.3 but not Kv1.2. The chemically synthesized product exhibited the same physiological activity and identical molecular mass (3933.7 Da) as the native toxin. 相似文献
997.
Yves Claustre Danielle De Peretti Philippe Brun Christiane Gueudet Nathalie Allouard Richard Alonso Jo?lle Lourdelet André Oblin Gabrielle Damoiseau Dominique Fran?on Marie-Fran?oise Suaud-Chagny Régis Steinberg Mireille Sevrin Hans Schoemaker Pascal George Philippe Soubrié Bernard Scatton 《Neuropsychopharmacology》2003,28(12):2064-2076
SSR181507 ((3-exo)-8-benzoyl-N-[[(2S)7-chloro-2,3-dihydro-1,4-benzodioxin-1-yl]methyl]-8-azabicyclo[3.2.1]octane-3-methanamine monohydrochloride) is a novel tropanemethanamine benzodioxane derivative that possesses high and selective affinities for D2-like and 5-HT(1A) receptors (K(I)=0.8, 0.2, and 0.2 nM for human D(2), D(3), and 5-HT(1A), respectively). In vivo, SSR181507 inhibited [(3)H]raclopride binding to D(2) receptors in the rat (ID(50)=0.9 and 1 mg/kg, i.p. in limbic system and striatum, respectively). It displayed D(2) antagonist and 5-HT(1A) agonist properties in the same concentration range in vitro (IC(50)=5.3 nM and EC(50)=2.3 nM, respectively, in the GTPgammaS model) and in the same dose range in vivo (ED(50)=1.6 and 0.7 mg/kg, i.p. on striatal DA and 5-HT synthesis, respectively, and 0.03-0.3 mg/kg, i.v. on dorsal raphe nucleus firing rate). It selectively enhanced Fos immunoreactivity in mesocorticolimbic areas as compared to the striatum. This regional selectivity was confirmed in electrophysiological studies where SSR181507, given acutely (0.1-3 mg/kg, i.p.) or chronically (3 mg/kg, i.p., o.d., 22 days), increased or decreased, respectively, the number of spontaneous active DA cells in the ventral tegmental area, but not in the substantia nigra. Moreover, SSR181507 increased both basal and phasic DA efflux (as assessed by microdialysis and electrochemistry) in the medial prefrontal cortex and nucleus accumbens, but not in the striatum. This study shows that the combination of D(2) receptor antagonism and 5-HT(1A) agonism, in the same dose range, confers on SSR181507 a unique neurochemical and electrophysiological profile and suggests the potential of this compound for the treatment of the main dimensions of schizophrenia. 相似文献
998.
Luiz A Benvenuti Francisco O S Fran?a Kátia C Barbaro José R Nunes Jo?o L C Cardoso 《Toxicon》2003,42(3):331-334
A 36-year old woman was bitten on the left ankle by a Bothrops jararacussu, and died 45 min after the bite. At necropsy, there were local signs of envenoming with haemorrhage, thrombosis and necrosis of the subcutaneous and muscular tissue. Multiple fibrin and platelet thrombi were found in the microcirculation of the heart and lungs, suggesting the occurrence of disseminated intravascular coagulation. Pulmonary haemorrhage probably secondary to the action of haemorrhagins, consumption coagulopathy and disseminated intravascular coagulation was the immediate cause of death. Intravenous inoculation of the venom could have occurred in the present case, which would explain the rapid onset of coagulation disorders, haemorrhage and death. 相似文献
999.
José Maria dos S Vieira Maria Teresa de P Azevedo Sandra Maria Feliciano de Oliveira Azevedo Ricardo Yukio Honda Benedito Corrêa 《Toxicon》2003,42(7):709-713
During the monitoring of toxic cyanobacteria in the Utinga Reservoir, which is the main drinking water supply for the city of Belém, PA, Brazil, a Radiocystis fernandoi strain (SPC714) was isolated. This non-axenic strain was submitted to a toxicity bioassay with mice and microcystin production analyzed by HPLC-DAD. The species was identified based on cultured and natural preserved material. Morphometric, developmental and reproductive characteristics were analyzed. The strain was cultured in liquid ASM-1 medium, at 25+/-1 degrees C, at an incident irradiance of 20 micromol photon m(-2)s(-1) and constant aeration. At the end of the exponential growth phase, cells were lyophilized and submitted to toxicity tests. The strain showed high toxicity to mice, by intraperitoneal route, with an approximate LD100 of 60 mg kg(-1) of body weight, producing characteristic symptoms of hepatotoxicity. Analyses performed by HPLC-DAD confirmed the production of microcystins, in a concentration of 3.83 microg mg(-1) of lyophilized cells. This is the first reference related to the toxicity of the genus Radiocystis. 相似文献
1000.
Fernanda B Nunes Cássio M Graziottin José Carlos F Alves Filho Adroaldo Lunardelli Melissa G S Pires Paulo H W?chter Jarbas R De Oliveira 《Pharmacological research》2003,47(1):35-41
Tissue lesion mechanisms provoked by sepsis include the infectious process, inflammation, and cellular energy deficit. We chose to test fructose-1,6-bisphosphate (FBP) because of its possible anti-inflammatory and antimicrobial actions. Wistar rats were used and divided into three experimental groups: a control group (n=10), in which a capsule was introduced into the peritoneum of the animals; a septic group (n=10), in which a capsule containing non-sterile fecal matter was introduced together with Escherichia coli (1.5 x 10(9)CFU); and a septic group treated with FBP 500 mg/kg (n=10). The blood cell tests revealed that levels of leukocytes increased significantly in the septic group when compared to both the septic group treated with FBP and the control group. The blood cultures were 100% positive in both the septic group and the septic group treated with bisphosphorylated sugar. The antibiogram only revealed an inhibitory halo in the case of the antibiotic ampicillin, there was no such indication for FBP. The anti-inflammatory power of FBP remained at 60% for 5 h in the rats that received the carrageenan injection. What is more, the sugar reduced the levels of ionic calcium in relation to the control group. This data proves the validity of using FBP in the treatment of sepsis, possibly due to its anti-inflammatory rather than antimicrobial action. 相似文献