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Biomedical subjects

Y Fujishima

Publications and source records attributed to Y Fujishima.

At least 37 records · Page 2Linked to original sources
PubMed1993

Nucleotide sequence of 5' portion of srfA that contains the region required for competence establishment in Bacillus subtilus.

The nucleotide sequence of the 20,535 base pairs of the 5' end of the srfA operon, containing the region required for competence development, was determined. This included the srfA promoter region, the first open reading frame, srfAA, encoding surfactin synthetase I and part of the second open reading frame, srfAB, encoding surfactin synthetase II. Three amino acid-activating domains characteristic of those found in peptide synthetases could be discerned in both srfAA (activating Glu, Leu and D-Leu) and srfAB (activating Val, Asp, and D-Leu). The presence of a conserved spacer motif in the amino-terminal end of srfAA suggests that the srfAA product may not initiate surfactin synthesis. The portion of srfA that contains the region required for competence is composed of srfAA and the first amino acid-activating domain of srfAB.

Amino Acid Sequence↗
PubMed1993

Spinal cord infarction associated with primary antiphospholipid syndrome in a young child. Case report.

Antiphospholipid antibodies have been reported to occur in ischemic stroke patients, but there have been no previous reports linking these antibodies to spinal cord infarction. A case of spinal cord infarction associated with primary antiphospholipid syndrome in a 6-year-old boy is reported. Magnetic resonance imaging clearly demonstrated marked swelling of the thoracolumbar spinal cord with gadolinium-diethylenetriamine pentaacetic acid enhancement at an acute stage, followed later by cord atrophy. Serological study disclosed positive lupus anticoagulant and immunoglobulin G anticardiolipin antibody. It is suggested that the role of antiphospholipid antibodies as an etiological factor for spinal cord ischemia should be recognized among causes that might have been categorized as either spontaneous spinal cord infarction or myelitis.

Antibodies, Anticardiolipin↗
PubMed1993

[Analysis of handwriting by the dynamic programming matching].

We examined the temporal invariance hypothesis in handwriting, using dynamic programming (DP) matching algorithm. The DP matching algorithm was originally developed for the speech recognition to eliminate fluctuations of time axis caused by different speech rates. This algorithm can determine the optimal point-to-point correspondences (warping function) between the standard velocity pattern and different patterns. We found that this algorithm worked well for various velocity patterns, even when their total writing time was different from the standard pattern. Only 30 to 50 percent of handwriting movements showed temporal invariance. The writing movements which didn't show temporal invariance consisted of several sub-motor units. The borders between the units were not limited near the end of each letter. The results suggest that handwriting of a word does not show the temporal invariance and that it is executed by some discrete sub-motor units.

Adult↗
PubMed1991

Histamine H2-receptor in atrium: signal transduction and response.

We have examined the signal transduction for H2-receptor mediated positive chronotropic response of guinea-pig right atrium. Our results indicate that phospholipid methylation is rapidly induced by histamine acting on H2-receptor in guinea-pig right atrium and therefore plays a predominant role in the signal transfer of H2-receptor-mediated cyclic AMP generation to exert positive chronotropic effect of atrium, as well as GTP-binding protein activation.

Adenylyl Cyclases↗
PubMed1991

Photodynamic therapy using pheophorbide a and Nd:YAG laser.

The authors describe a new photodynamic therapy (PDT) method for malignant brain tumors. Pheophorbide a (Ph-a), the photosensitizer, has low toxicity, causes no skin sensitization and is activated with an acoustic Q switched neodymium yttrium-argon-garnet (Nd:YAG) laser which achieves deep tissue penetration. The Ph-a distribution in Fisher 344 (F344) rats bearing rat T9 glioma at 24 hours after intravenous injection was very low in the normal brain tissue, but significantly higher in the T9 glioma giving a tumor to normal brain tissue concentration ratio of 7.5:1. The in vitro survival rate of T9 glioma cells pretreated with Ph-a was 68.8 +/- 5.4% after laser irradiation for 20 minutes, significantly lower than in the control groups. This indicates that Ph-a was activated with the acoustic Q switched Nd:YAG laser causing the photodynamic effect. The survival rate after Ph-a pretreatment and laser irradiation in a waterbath at 44.0 degrees C was further reduced to 15.8 +/- 3.3%. In vivo PDT studies using T9 glioma cells inoculated into the dorsal region of F344 rats showed tumor eradication in four of six rats. The combination of PDT and laser hyperthermia produced tumor eradication in all six rats. The combination of PDT and hyperthermia is a promising method for tumor treatment.

Animals↗
PubMed1990

Molecular weight analysis of isopenicillin N synthase by electrospray mass spectrometry.

The use of electrospray mass spectrometry as a tool in analytical biochemistry was illustrated by determination of the molecular weights of wildtype and recombinant isopenicillin N synthase (IPNS). The molecular weight of recombinant IPNS produced using an expression system which generated soluble protein was found to be between 38,364 and 38,376 Da, ca 60 mass units higher than that of the wildtype material, consistent with the presence of an additional N-terminal glycine in the former. Observed molecular weights were all ca 70 Da higher than that calculated from sequence information, consistent with the complexion of a partially hydrated iron atom to the enzyme during analysis.

Escherichia coli↗
PubMed1990

[The Sistrunk median cervical cyst operation using a cecal foramen pointer].

The cecal foramen pointer was invented for a Sistrunk median cervical cyst operation. The instrument consists of three elements, namely: The cecal foramen holder, the giraffe shaped connector and the pointer needle. First of all, the cecal foramen is held by the holder which is reconstructed from hemostatic forceps. The one end of the connector is joined to the holder's handle. Then the other end of the connector comes along the patient's chin, in front of the neck. The cyst and mid-portion of the hyoid bone are dissected, followed by coring out of the thyroglossal duct toward the cecal foramen. In the coring out process, the pointer needle is pierced through the tunnel of the connector's opposite end, so that the needle top reaches to the bottom of operative wound. Then the needle shows exactly the direction to the cecal foramen and the distance from the bottom of the wound to the cecal foramen. By using this instrument the operation was successfully performed for a case of a recurrent median cervical cyst with a complete fistula to the cecal foramen.

Humans↗
PubMed1989

Restriction fragment length polymorphism analysis of major histocompatibility complex genes in the non-obese diabetic mouse strain and its non-diabetic sister strains.

It has been suggested that one of the recessive genes controlling diabetes in non-obese diabetic mice is linked to the major histocompatibility complex. We, therefore, performed restriction fragment length polymorphism studies of major histocompatibility complex genes (class I, II, and III) in non-obese diabetic mice in comparison with those of their non-diabetic sister strains, non-obese non-diabetic, cataract, and ILI mice which were derived from the same Jcl-ICR mice as the non-obese diabetic mouse was. When class II and III probes and a minimum of four restriction enzymes were used, class II and III genes of non-obese diabetic mice were indistinguishable from those of cataract and ILI mice but totally different from those of non-obese non-diabetic mice. The studies also indicated that A beta, E beta, and C4-Slp genes of non-obese diabetic, cataract, and ILI mice, and A alpha, A beta, E beta and C4-Slp genes of non-obese non-diabetic mice are different from those of BALB/c and C57BL/6 mice, respectively. While non-obese non-diabetic mice expressed the E alpha gene, non-obese diabetic, cataract, and ILI mice appeared to carry a deletion in the 5' end of the E alpha gene resulting in failure to transcribe the E alpha gene. When class I probe was used, cataract mice showed very different band patterns from those of the other ICR-derived mice. It is suggested that non-obese diabetic, non-obese non-diabetic, and ILI mice contain only a single class I D region gene.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Change in cytoplasmic free Ca2+ concentration in rabbit platelets contacting with albumin coated and uncoated polystyrene surfaces.

Direct measurement of cytoplasmic free Ca2+ concentration in rabbit platelets in contact with polystyrene latexes was examined by monitoring an intracellular trapped fluorescent indicator dye, Fura 2, as a quantitative evaluation of platelet activation on material surfaces. It was found that an increase in cytoplasmic free calcium levels in platelets in contacting latexes was strongly reduced by the adsorption of albumin on the latex surfaces. Further, such an elevation of cytoplasmic free calcium levels was found to require a calcium influx from an extracellular medium across the platelet-plasma membrane.

Animals↗
PubMed1989

[Subacute myeloneuropathy after abuse of nitrous oxide: an electron microscopic study on the peripheral nerve].

We have experienced a case of myeloneuropathy following habitual abuse of nitrous oxide. We report clinical and pathological findings of this case with review of literatures. A 36-year-old dentist was first admitted to our hospital on August 17, 1983 because of numbness of both lower legs and unsteady gait. He had recreationally inhaled nitrous oxide 30 to 60 minutes everyday since a year ago. Neurological examination showed ataxic broad-based gait, moderate loss of pain and touch sensation in the lower limbs up to patella. Position and vibratory senses were more severely impaired. Deep tendon reflexes increased in the upper extremities and at the knees, but diminished at ankle jerks. Muscle strength was normal. Prominent Lhermitte's sign was present. Except for reduced serum vitamin B12 level, laboratory results were normal. Needle electromyography showed high amplitude and long duration NMU in the right quadriceps and anterior tibial muscles. Motor nerve conduction velocity was 34 m/sec at the right posterior tibial nerve and could not be detected at the left. Sural nerve biopsy was performed. The density of the myelinated fibre measured on transverse section was in normal range but degenerated fibres were occasionally recognized. Single teased nerve fibre showed various degree of myelin ovoid along the fibre. Myelin loss was shown to occur in some parts of the fibre. Electron microscopy showed myelin splitting and formation of intramyelinic vacuoles containing myelin debris. Axon was almost normal at least in the early stage of degeneration. Later, axon disappeared with destruction of myelin sheath. These nerve changes largely demonstrated demyelination but it was occasionally accompanied with axonal degeneration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Synthesis of the optically active 4-O-phosphono-D-glucosamine derivatives related to the nonreducing-sugar subunit of bacterial lipid A.

The optically active lipid A-subunit homologs named GLA-46, GLA-47, GLA-59, and GLA-60 have been synthesized stepwise by successive acylation at N-2 and O-3 of benzyl 2-amino-2-deoxy-4,6-O-isopropylidene-beta-D-glucopyranoside with the 3-9O-(benzyloxy)methyl or 39O-tetradecanoyl derivative of optically active 3-hydroxytetradecanoic acid, and phosphorylation at O-4 of the D-glucosamine residue.

Glucosamine↗