Biomedical subjects
Publications and source records attributed to Kenji Mori.
The N,O-diacetyl derivative of (+)-xestoaminol C (2-amino-3-tetradecanol, 1), an inhibitor of reverse transcriptase isolated from Xestospongia sp., was synthesized from (S)-alanine, and its absolute configuration was determined as 2S, 3R.
We report a case of a bacterial brain abscess presenting symptoms of 'sudden stroke-like' onset, associated with infective endocarditis. A 59-year-old woman experienced a sudden stroke-like onset of left hemiplegia. Computed tomography (CT) and magnetic resonance imaging (MRI) were performed on the day of ictus. No lesion responsible for the symptom was seen on either CT or a T2 weighted image (T2WI), but a diffusion-weighted image (DWI) revealed focal increased signal intensity in the right frontal lobe. An initial diagnosis of acute embolic infarction associated with infective endocarditis was made. Although the patient's neurological state had been stable, motor paresis of her left extremities became worse starting one month after her admission. MRI with gadolinium-diethylenetriaminepenta-acid (Gd-DTPA) at 37 days after admission showed an irregular-shaped ring-enhancement lesion located at the same place as the initial infarction, and in the left frontal lobe. Surgical drainage of the lesion in the right frontal lobe was performed, and diagnosed as a bacterial abscess. The exact mechanism of a bacterial brain abscess presenting with 'sudden stroke-like' onset is unknown, but various hypotheses have been proposed. One is that paroxysmal septic emboli lead to abscess formation within or near the area of embolic infarction. Our case showed that the creation of a brain abscess followed embolic strokes, and that this hypothesis was demonstrated by MRI carried out on the day of ictus.
Clinical effects of risperidone were evaluated in 9 young autistic children under informed consent of their parents. The patients were evaluated by the Children's Behavioral Checklist and Rutter's Autistic Behavioral Rating Scale. After the administration, two subjects (playing and adaptation to change) of the Children's Behavioral Checklist and four (anomalous autistic behavior, destructive behavior, developmental problem and activity level) of the Rutter's Autistic Behavioral Rating Scale were improved significantly. There were no serious side effects such as extrapyramidal symptoms except minor adverse effects including sedation, depression, increased appetite and constipation. Risperidone might be effective for serious behavioral disturbances in young autistic children.
(R)-(-)-Elenic acid (R-2,4-dimethyl-22-(p-hydroxyphenyl)-docos-3(E)-enoic acid) (EA) is a DNA topoisomerase II inhibitor found in an Indonesian sponge, Plakinastrella sp. We found and report here that it is a potent inhibitor of calf DNA polymerase alpha (IC(50)=7.7 microM) and rat DNA polymerase beta (IC(50)=12.9 microM). EA did not bind to DNA directly. EA did not influence the activities of DNA polymerases such as plant DNA polymerases I and II and prokaryotic DNA polymerases such as Escherichia coli DNA polymerase I, or other DNA metabolic enzymes such as human immunodeficiency virus (HIV) reverse transcriptase, T7 RNA polymerase and bovine deoxyribonuclease I. Interestingly, EA was also an inhibitor of DNA topoisomerases I and II, although the enzymatic characteristics including modes of action, amino acid sequences and three-dimensional structures were markedly different from those of DNA polymerases. EA could prevent the growth of NUGC-3 cancer cells, and the LD(50) value was 22.5 microM. The cells were halted at G1 and G2/M phase in the cell cycle. From these results, the action mode of EA is discussed.
All of the four stereoisomers of 3,12-dimethylheptacosane were synthesized from the enantiomers of citronellal. (Z)-9-Pentacosene and (Z)-9-heptacosene were also synthesized. These hydrocarbons are the characteristic components of the cuticular hydrocarbons of the queen of the ant, Diacamma sp..
6-Acetoxy-19-methylnonacosane (1), 7-acetoxy-19-methylnonacosane (2), 8-acetoxy-19-methylnonacosane (3), 7-acetoxy-15-methylnonacosane (4), and 21-methyl-7-hentriacontanone (5) were synthesized as racemic and diastereomeric mixtures. These are new compounds isolated from an HPLC fraction of the female hexane extract which elicited mating responses in the male screwworm fly, Cochliomyia hominivorax.
The ceramide sex pheromone [(2S,2'R,3S,4R)-2-(2'-hydroxy-21-methyldocosanoylamino)-1,3,4-pentadecanetriol (1)] of the female hair crab (Erimacrus isenbeckii) was synthesized by starting from (S)-serine and 12-bromo-1-dodecanol.
The absolute configuration of (-)-koninginin A [10-hexyl-11, 12-dioxatricyclo[7.2. 1.0<1 ,6>]dodecane-2,5-diol (1)], the antibiotic metabolite of Trichoderma koningii and T. harzianum, was determined as 1S, 2R, 5S, 6S, 9S, 10S by an X-ray crystallographic analysis of its synthetic sample coupled with the established stereochemical outcome of Sharpless asymmetric dihydroxylation used as the key reaction to prepare intermediate 4.
Cuticular hydrocarbons of the tsetse fly, Glossina brevipalpis, contain 3,7,11,15-tetramethylhentriacontane and 4,8,12,16-tetramethyldotriacontane as possible candidates for its contact sex pheromone. These were synthesized as racemic and diastereomeric mixtures starting from racemic citronellol and employing phenyl-sulfone-mediated chain-elongation as the key reaction.
(1R,2S)-1-(3'-Chloro-4'-methoxyphenyl)-1,2propanediol (Trametol, 3), a metabolite of the fungus Trametes sp. IVP-F640 and Bjerkandera sp. BOS55, was synthesized by employing Sharpless asymmetric dihydroxylation as the key step. Similarly, the (1R,2S)-isomer of 1-(3',5'-dichloro-4'-methoxyphenyl)-1,2-propanediol (4), another metabolite of Bjerkandera sp. BOS55, was synthesized by asymmetric dihydroxylation.
Novel 2,3:4,6-di-O-isopropylidene-alpha-D-glucopyranosyl-(1,1)-4,6-O-isopropylidene-2,3-di-O-diphenylphosphino-alpha-D-glucopyranoside (2), 2,3:4,6-di-O-cyclohexylidene-alpha-D-glucopyranosyl-(1,1)-4,6-O-cyclohexylidene-2,3-di-O-diphenylphosphino-alpha-D-glucopyranoside (4), and 2,3:4,6-di-O-cyclohexylidene-beta-D-glucopyranosyl-(1,1)-4,6-O-cyclohexylidene-2,3-di-O-diphenylphosphino-beta-D-glucopyranoside (11) were prepared from the corresponding alpha,alpha- or beta,beta-trehalose. The ligands were transformed into cationic Rh complexes, such as [Rh(alpha-D-glucopyranosyl-(1,1)-2,3-di-O-diphenylphosphino-alpha-D-glucopyranoside)(cod)]BF(4) (3) and [Rh(beta-D-glucopyranosyl-(1,1)-2,3-di-O-diphenylphosphino-beta-D-glucopyranoside)(cod)]BF(4) (12) bearing free hydroxy groups. These complexes were soluble in water and were efficient catalysts for the asymmetric hydrogenation of dehydroamino acids and their esters in water or an aqueous/organic biphasic medium with high enantioselectivity (up to 99.9% ee). Aqueous biphasic systems offer an easy separation of the aqueous catalyst phase from the product phase and allow recycling of the catalyst phase without the loss of enantioselectivity.
Magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (proton MRS) findings before and after carnitine therapy in a patient with methylmalonic acidemia (MMA) are evaluated. The hyperintensity on T2-weighted image and diffusion-weighted image and the decreased apparent diffusion coefficient of bilateral basal ganglia were normalized in parallel with normalization of the elevated lactate levels and the decreased N-acetyl-aspartate levels, corresponding to improvement of clinical symptoms. MRI and proton MRS may serve as a suitable, noninvasive modality for monitoring treated MMA.