Isolation of a Drosophila Gene Encoding a Head-Specific Guanylyl Cyclase

Abstract: We have isolated and characterized a new guanylyl cyclase gene ( dgcl) in Drosophila. The deduced amino acid sequence (683 amino acids) most closely resembled the mammalian solubletype guanylyl cyclase α subunit. The cyclase catalytic domain was highly conserved between the mammalian and Drosophila guanylyl cyclases. The dgcl mRNA was detected in wild-type heads but not in bodies, and its level was reduced in the mutant eyes absent (eya) , indicating that dgcl is preferentially expressed in the CNS and in the eye. The enriched distribution in the eye suggests that dgcl may have a role in phototransduction.     

Biosynthèse de la cellulose bacterienne deutériée: étude par R. M. N. du taux d'incorporation et de la localisation du deutérium

The use of the NMR spectra (250 MHz) of cellulose triacetate allows the determination of the percentage of deuterium bonded to each of the six carbon atoms of the monomer residue (except for H_?1 and one of the protons bonded to C₆ where the signals overlap). Deuterated derivatives of D -glucose and/or deuterated water were used for the biosynthesis of bacterial cellulose by Acetobacter xylinum. Analysis of NMR spectra of acetylated samples gives the following results. About 90% of the protons linked to C₁ and C₆ come from the D -glucose used in the nutrition medium, whereas 10% are exchanged with other sources of protons. Over 40% of the protons linked to C₂, C₃, C₄, and C₅ arise from the water of the nutrition medium. Discrepancies between results of biosynthesis from deuterated water and from deuterated D -glucose can only be explained if more than one enzymatic process is involved in the biosynthesis of bacterial cellulose.     

Prolonged and variable intervals between EEG complexes in subacute inclusion body encephalitis

Should effective therapy of SIBE ever depend upon early diagnosis, periodic EEG complexes must be sought carefully when the condition is suspected, bearing in mind that initially the duration of intervals between complexes may be more prolonged and more variable than commonly appreciated. Prolonged, uninterrupted recording at reduced speed, taken both while the patient is awake and asleep, may well facilitate recognition of periodic events as unusual as those observed in the 20-year-old young man described in this paper, who was examined during the early stage of the disease. When initial EEG complexes are separated, as in our patient, by variable and prolonged intervals — up to 86 seconds'' duration — their periodicity and diagnostic implication can be overlooked, particularly in a so-called routine electroencephalogram. Optimal dispaly of such unusual findings calls for suitable electroencephalographic techniques.     

Hepatic disposition of organic anions in rats infested with Fasciola hepatica

This study was undertaken to investigate the effects of subclinical fascioliasis at various stages of its development (3, 6, and 11 weeks after infestation with an oral dose of 20 metacercariae of Fasciola hepatica) on the hepatobiliary transport of organic anions in rats. Basal bile acid secretion was not significantly modified in infested rats as compared to the controls but there was a significantly increased bile flow in the 11-week group. In all infested rats, maximal biliary excretion and cumulative excretion of bromosulphthalein was significantly reduced, although there was a tendence to recovery in the 11-week infested group. Decreased biliary secretion was accompanied by increased plasma and liver concentrations of bromosulphthalein. Glutathione S-transferase activity was significantly reduced by Weeks 3 and 6 postinfestation. Liver glutathione concentration was significantly reduced in all infested rats. Maximal excretion of dibromosulphthalein, a compound not biotransformed in the liver, fell by Week 6 postinfestation and recovered a normal value thereafter. These results indicate that effects of experimentally induced fascioliasis on hepatic disposition of organic anions depend upon the stage of its development and that are a consequence of both metabolism and transport related factors.