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1.  The non-dystrophic myotonias: molecular pathogenesis, diagnosis and treatment 
Brain  2009;133(1):9-22.
The non-dystrophic myotonias are an important group of skeletal muscle channelopathies electrophysiologically characterized by altered membrane excitability. Many distinct clinical phenotypes are now recognized and range in severity from severe neonatal myotonia with respiratory compromise through to milder late-onset myotonic muscle stiffness. Specific genetic mutations in the major skeletal muscle voltage gated chloride channel gene and in the voltage gated sodium channel gene are causative in most patients. Recent work has allowed more precise correlations between the genotype and the electrophysiological and clinical phenotype. The majority of patients with myotonia have either a primary or secondary loss of membrane chloride conductance predicted to result in reduction of the resting membrane potential. Causative mutations in the sodium channel gene result in an abnormal gain of sodium channel function that may show marked temperature dependence. Despite significant advances in the clinical, genetic and molecular pathophysiological understanding of these disorders, which we review here, there are important unresolved issues we address: (i) recent work suggests that specialized clinical neurophysiology can identify channel specific patterns and aid genetic diagnosis in many cases however, it is not yet clear if such techniques can be refined to predict the causative gene in all cases or even predict the precise genotype; (ii) although clinical experience indicates these patients can have significant progressive morbidity, the detailed natural history and determinants of morbidity have not been specifically studied in a prospective fashion; (iii) some patients develop myopathy, but its frequency, severity and possible response to treatment remains undetermined, furthermore, the pathophysiogical link between ion channel dysfunction and muscle degeneration is unknown; (iv) there is currently insufficient clinical trial evidence to recommend a standard treatment. Limited data suggest that sodium channel blocking agents have some efficacy. However, establishing the effectiveness of a therapy requires completion of multi-centre randomized controlled trials employing accurate outcome measures including reliable quantitation of myotonia. More specific pharmacological approaches are required and could include those which might preferentially reduce persistent muscle sodium currents or enhance the conductance of mutant chloride channels. Alternative strategies may be directed at preventing premature mutant channel degradation or correcting the mis-targeting of the mutant channels.
doi:10.1093/brain/awp294
PMCID: PMC2801326  PMID: 19917643
ion channels; neuromuscular; genetics; EMG
2.  NEONATAL HYPOTONIA CAN BE A SODIUM CHANNELOPATHY: RECOGNITION OF A NEW PHENOTYPE 
Neurology  2008;71(21):1740-1742.
doi:10.1212/01.wnl.0000335269.21550.0e
PMCID: PMC2676969  PMID: 19015492
3.  S-methyl glutathione synthesis is catalyzed by the cheR methyltransferase in Escherichia coli. 
Journal of Bacteriology  1986;165(3):958-963.
The cheR methyltransferase, known to be necessary for the methyl esterification of receptors involved in chemotaxis, is shown to be essential to the synthesis of S-methyl glutathione from glutathione and S-adenosylmethionine in intact Escherichia coli. S-Methyl glutathione is not, however, found to be essential for chemotaxis. It is suggested that the synthesis of S-methyl glutathione may be due to a "parasitic" reaction of glutathione with S-adenosylmethionine bound to the methyltransferase.
PMCID: PMC214522  PMID: 3512532
4.  Regulation of the cellulolytic system in Trichoderma reesei by sophorose: induction of cellulase and repression of beta-glucosidase. 
Journal of Bacteriology  1980;144(3):1197-1199.
Sophorose has two regulatory roles in the production of cellulase enzymes in Trichoderma reesei: beta-glucosidase repression and cellulase induction. Sophorose also is hydrolyzed by the mycelial-associated beta-glucosidase. Repression of beta-glucosidase reduces sophorose hydrolysis and thus may increase cellulase induction.
PMCID: PMC294792  PMID: 6777367
5.  Induction of cellulolytic enzymes in Trichoderma reesei by sophorose. 
Journal of Bacteriology  1979;139(3):761-769.
Sophorose (2-O-beta-glucopyranosyl-D-glucose) induces carboxymethyl cellulase in Trichoderma reesei QM6a mycelium with 1.5 to 2 h. The induction response to sophorose concentration, although complicated by the metabolism of sophorose, shows saturation kinetics. Most of the cellulase appears after most of the sophorose has been taken up, but the presence of an inducer is required to maintain cellulase synthesis because enzyme production ceases after separation of the mycelium from the induction medium. Cellulase appears simultaneously in the medium and in the mycelium, and no appreciable levels accumulate in the mycelium. Response to pH suggest either that synthesis and secretion of the enzyme are closely associated or concurrent events affected by surface interactions with the medium. Effects of temperature and pH on cellulase induction by sophorose are similar to those reported for induction by cellulose. The kinetics of absorption by mycelium differs from that of other beta-linked saccharides and glucose, the uptake of sophorose being much slower. Under our cultural conditions, sophorose appears to induce an incomplete array of cellulase enzymes, as indicated by enzymatic and electrophoretic studies.
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PMCID: PMC218020  PMID: 39061
6.  Immobilization of Aspergillus beta-glucosidase on chitosan. 
beta-Glucosidase of Aspergillus phoenicis QM 329 was immobilized on chitosan, using the bifunctional agent glutaraldehyde. The most active preparation based on the amount of support contained a 1:2.5 enzyme-to-chitosan ratio (wt/wt). However, the specific activity of the bound enzyme decreased from 10 to 1% with increasing enzyme-to-chitosan ratio. Compared with free beta-glucosidase, the immobilized enzyme exhibited: (i) a similar pH optimum but more activity at lower pH values; (ii) improved thermal stability; (iii) a similar response to inhibition by glucose; and (iv) mass transfer limitations as reflected by higher apparent Km and lower energy of activation.
PMCID: PMC242917  PMID: 25624
7.  Beta-glucosidase of Trichoderma: its biosynthesis and role in saccharification of cellulose. 
The extracellular beta-glucosidase of Trichoderma viride generally is present in low levels when the organism is cultured on cellulose because it is inactivated under the acid conditions which develop in the medium while the other enzymes of the cellulase complex are more stable. With the appropriate pH control, inactivation of beta-glucosidase is prevented and the activity of this enzyme increases during growth. In the saccharification of crystalline cellulose, or of cellulose at low concentrations, much of the glucose produced is the result of the cleavage of cellobiose by beta-glucosidase. However when high concentrations (10%) of pretreated cellulose are saccharified, significant quantities of glucose are produced by action of enzymes other than beta-glucosidase.
PMCID: PMC291170  PMID: 5951

Results 1-7 (7)