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Biomedical subjects

T Beppu

Publications and source records attributed to T Beppu.

At least 379 records · Page 21Linked to original sources
PubMed1978

Crystallization and positional specificity of hydroperoxidation of Fusarium lipoxygenase.

A lipoxygenase obtained from the fungus Fusarium oxysporum was purified and crystallized. Using the purified enzyme, the positional specificity of linoleate peroxidation was studied. Linoleate hydroperoxides were converted into the corresponding trimethylsilyl derivative by reduction, catalytic hydrogenation and treatment with hexamethyldisilazane/trimethylchlorosilane/pyridine and then analyzed by combined gas-liquid chromatography-mass spectrometry. Fusarium lipoxygenase was found to produce 9- or 13-hydroperoxy-octadecadienoates from linoleate. The ratio of 9- to 13-hydroperoxides produced by the enzyme was also determined by high performance liquid chromatography of their methyl esters. When the enzymic reaction proceeded at pH 9.0 and 12.0, the ratio of 9- to 13-hydroperoxide isomers was 70 : 30 and 56 : 44, respectively. With the use of the heavy isotope of oxygen (18O2), atoms of oxygen introduced into hydroperoxides were found to be derived from the gaseous phase and not from the aqueous phase.

Crystallization↗
PubMed1978

Echo guided percutaneous transhepatic cholangiography with puncture transducer.

Conventional percutaneous transhepatic cholangiography (PTC) has some disadvantages because it is customarily performed blindly. If the bile duct is made visible, these disadvantages are eliminated. The biliary tree, if dilated, can be clearly delineated by ultrasound technique. By combining the B-mode examination of the biliary tract with the ultrasonic puncture transducer, percutaneous transhepatic cholangiography was performed successfully in 16 examinations on 12 patients. PTC needle could be inserted directly into the lumen of the bile duct without appreciable difficulty. The echo guided PTC was found to be an easier, safer, and more reliable method than the conventional blind technique.

Aged↗
PubMed1978

[Normal pressure hydrocephalus. Part 1. Dynamic study of CSF circulation in patients with normal pressure hydrocephalus (author's transl)].

To clarify the pathogenesis of normal pressure hydrocephalus (NPH), quantitative measurement of CSF dynamics was attempted using RI techniques. In this study results concerning RI ventriculography and RI transfer test from CSF to plasma were reported. "Barrier ratio" and regional cerebral blood flow study in NPH will be reported elsewhere. Fifty-three patients with chronic communicating hydrocephalus wer devided into two groups. Thus, twenty-seven cases were diagnosed as NPH according to clinical symptoms and signs, and others were considered as mere chronic communicating hydrocephalus without any NPH characteristics. Results are as follows: 1) 169Yb--DTPA ventriculography; In NPH group, there was longer retention of RI injected into lateral ventricle, and RI activity was not detected in the cisterna magna 60 minutes after the injection. These findings show remarkable delay of CSF flow in NPH patients. 2) Transfer test of 169Yb--DTPA from CSF to plasma; Immediately after the RI injection, Transfer ratio of RI activity from CSF to plasma was measured. It was revealed that intraventricular RI was more rapidly transfered to plasma in NPH group compared with in the control group, suggesting accelerated trans-ependymal absorption of RI in NPH group.

Aged↗
PubMed1978

[Normal pressure hydrocephalus. Part 2. The evaluation of severity of cerebral dysfunction by measurement of "barrier ratio" and regional cerebral blood flow (author's transl)].

In the previous study, quantitative analysis of RI ventriculography was reported in fifty-three cases with chronic communicating hydrocephalus. In this study, according to the same criteria as that of previous report, fifty-three cases were divided into two groups, namely NPH group (twenty-seven cases) and control group, which were considered as mere chronic communicating hydrocephalus without and NPH chalacteristics. (twenty-six cases). Results of "barrier ratio (B.R.)" measurement and regional cerebral blood flow study in these cases are as follows: 1) "Barrier ratio" using of 99mTcO4-: Concerning about B.R. of 99mTcO4- there was no significant difference between NPH and control group. However it tends to be that shunt surgery is not so effective in NPH cases in which B.R. shows abnormally low value. 2) rCBF by 133Xe clearance method: Regional cerebral blood flow was diffusely decreased in NPH patients, especially in its frontal area, suggesting the frontal area would be more severely damaged in NPH cases. These findings leads us to the conclusion that whether the shunt surgery might be effective or not depends on severity of cerebral dysfunction and the cerebral dysfunction is clearly evaluated by RI technique mentioned above.

Adult↗
PubMed1977

Molecular cloning and in vitro transcription of Bacillus subtilis plasmid in Escherichia coli.

A composite plasmid (pAT2010) has been constructed in vitro from RSF2124 and Bacillus subtilis IFO3022 plasmid (pAT1060) by covalent joining of the two DNA molecules by means of Escherichia coli DNA ligase through the cohesive ends generated by restriction endonuclease RI (EcoRI) cleavage. The composite plasmid was selected by transformation of E. coliC600r-m- with the ligated mixture after enrichment for composite plasmid by preparative agarose gel electrophoresis, and plating of the transformants on a medium containing ampicillin and colicin E1. Treatment of the composite plasmid with EcoRI yielded two fragments corresponding to the linear forms of the parental plasmids. The composite plasmids replicated as biologically functionally units in E. coli, and expressed genetic information carried by RSF2124. In the presence of chloramphenicol, the composite plasmids continued to replicate and the copy number gradually increased. Such nature of replication in the presence of chloramphenicol is characteristic to RSF2124 derived from colicin E1 factor, and so it is suggested that the replicator of RSF2124 is functional in the composite plasmid. The composite plasmid was found to synthesize mRNA of B. subtilis plasmid in cell-free extracts of E. Coli, by hybridization of the mRNA to the original plasmid DNA of pAT1060.

Bacillus subtilis↗
PubMed1977

Restriction and modification in Bacillus species: genetic transformation of bacteria with DNA from different species, part I.

Host specific restriction was detected in 13 Bacillus strains, when 63 strains of Bacillus subtilis and 15 other Bacillus strains were tested with phage phi 105C. These 13 strains were classified into 8 groups (M,H,C,N,E,F,G,P) by the type of restriction. M-type strains (B. subtilis Marburg 168, its derivatives, and two other strains) showed relatively weak restriction, restricting phi 105C from other groups of Bacillus by ratios of 10(-1) to 10(-3). Strains of groups H,C,N,E,F,G, and P restricted phi 105C from other groups by ratios of 10(-2) to 10(-8). It was confirmed with some of the strains that type-specific modification was endowed only by the last host. Furthermore, we isolated one restriction deficient mutant of B. subtilis Marburg 168-YS11, which had also lost its modification phenotype.

Bacillus↗
PubMed1976

Purification and properties of the nuclease inhibitor of Aspergillus oryzae and kinetics of its interaction with crystalline nuclease O.

A nuclease inhibitor found in the mycelia of Aspergillus oryzae has been purified 158,000-fold by ammonium sulfate precipitation, chromatography on Sephadex G-75, DEAE-Sephadex A-50 and Bio-Gel p-60 columns, preparative disc electrophoresis on acrylamide gel, and electrofocusing in ampholite. The purified inhibitor is nearly homogeneous as judged by disc electrophoresis. It shows a typical ultraviolet absorption curve for protein, and the inhibitory activity is inactivated by chymotrypsin. The inhibitor and nuclease O (EC 3.1.4.9, a crystalline enzyme from the mycelia of the same organism) form a stable enzyme inhibitor complex. The molecular weights of nuclease O, the inhibitor and the enzyme inhibitor complex are estimated to be 46,000, 22,000 and 73,000 respectively, by Sephadex G-100 gel filtration. The isoelectric points of the enzyme and the inhibitor are 10.0 and 4.09, respectively, as determined by electrofocusing in ampholite. The inhibition is noncompetitive, and the inhibitor constant (K1) is 3.2 X 10(-12) M, whereas the Michaelis constant (Km) for DNA is 2.2 X 10(-8) M. The inactive enzyme-inhibitor complex is reactivated by chymotrypsin through inactivation of the inhibitor. The reactivated enzyme can be inactivated again by the inhibitor, which shows that desensitization of the enzyme does not occur by the action of chymotrypsin.

Aspergillus↗
PubMed1976

Antiviral antibiotic S15-1. Taxonomy of the producing strain and study of conditions for production of the antibiotic.

Strain S15-1 which produces antiviral antibiotic S15-1 belonging to the streptothricin group of antibiotics was isolated from a soil sample. Cell analysis, colony morphology, the absence of sporangia-like vesicles, the formation of spores in chains of the Rectus Flexibilis type, and the ability to produce melanoid pigment, indicate that this strain belongs to the genus Streptomyces Waksman and Henrici. A comparison of the characteristics of strain S15-1 with related Streptomyces show that it should be identified as Streptomyces purpeofuscus Yamaguchi and Saburi. The investigation of cultural conditions show that soluble starch and meat extract are the most suitable carbon and organic nitrogen sources for the production of antibiotic S15-1. Strain S15-1 grew poorly on media with no organic nitrogen sources, and did not produce the antibiotic. Antiviral antibiotic S15-1 is accumulated at the highest level after 3 or 4 days growth of the producing organism.

Anti-Bacterial Agents↗
PubMed1976

[A case of suprasellar tumor associated with so-called atypical angina pectoris].

A case of suprasellar tumor associated with so-called atypical angina pectoris was reported. A 58-year-old man was admitted to our hospital on Feb. 2, 1973, because of headache, disturbance of visual field and the attack of chest pain. He had been suffering from disturbance of visual field for about 3 years and the attack of chest pain for about 4 months prior to admission. Neurological findings on admission were bitemporal hemianopia, decreased visual acuity and atrophy of the optic disc. Bilateral carotid angiography showed upward displacement of A1 portion of the anterior cerebral artery. Pneumoencephalography demonstrated defect of the anterior part of the third ventricle. Laboratory examination showed hypopituitalism. On March 26, 1973, Right frontal craniotomy was performed under the diagnosis of suprasellar tumor. The walnut-sized tumor was detected in the suprasellar region and removed totally. Histological examination showed dermoid cyst. With regard to the attack of chest pain, the selective coronary angiography was performed. But organic change was not detected and Master's two step test did not induce any pathological finding in EEG. So we made a diagnosis of so-called atypical angina pectoris. There are many arguments about pathogenesis of so-called atypical angina pectoris. There is no organic change of the heart of attention now. Recently it is said that so-called atypical angina pectoris is closely connected with paradoxical sleep. We recognized dysunction of the autonomic nervous system through various examinations. The hypothalamus was displaced upward by a suprasellar tumor in this case. After removal of the suprasellar tumor, the frequency of the attack of chest pain was decreased. The atypical angina pectoris in the presented case may be considered to consequence of distrubance of the hypothalamic function.

Angina Pectoris↗
PubMed1976

[2 cases of unilateral hydrocephalus developing in the fetal period].

Dilatation of the lateral ventricle may occur as a result of unilateral hydrocephalus with obstruction of the foramen of Monro. Two cases with congenital dilatation of unilateral ventricle are presented, in which no obstruction of the foramen of Monro was demonstrated. The patients had infantile spasm, asymmetry of the skull and face, and contralateral hemiparesis. Angiography showed embryonal type of the middle cerebral artery. These findings suggest probable presence of active unilateral hydrocephalus in the fetal period.

Humans↗
PubMed1975

Inhibtory effect of colicin E2 on transport systems of Escherichia coli in the presence of the rex gene of lambda prophage.

Purified colicin E(2) was found to cause marked inhibition of the permeation rate of o-nitrophenyl-galactoside (ONPG) in several lambda-lysogenic strains of Escherichia coli in the presence of chloramphenicol to prevent prophage induction. The inhibitory effect of colicin E(2) on transport systems was analyzed with cells of E. coli CP78(lambda). The dose of colicin E(2) for the half-maximum inhibition of the ONPG-permeation rate was about 9 molecules of the colicin per bacterium under the aerobic condition, which corresponded to about 1 killing unit per bacterium. Kinetics of the transport of [(14)C]methylthiogalactoside suggested that colicin E(2) began to inhibit the influx rate of beta-galactosides within a few minutes after the colicin addition, and the maximum inhibition reached more than 80%. Extensive leakage of intracellular potassium ion and inhibition of l-proline transport also occurred at the same time. Acid solubilization of cellular deoxyribonucleic acid by the colicin was apparently delayed to the initiation of the transport inhibition. The extents of the inhibition of beta-galactoside transport and leakage of potassium ion by the colicin were extensive in cells lysogenic for wild lambda phage or lambdaind(-), whereas the extents were slight in the nonlysogenic cells or cells carrying lambdarex(-) prophage. It was concluded that the sensitization of membrane transport systems of E. coli cells to colicin E(2) was achieved by the presence of the rex gene product of lambda phage.

Biological Transport↗
PubMed1975

Penetration of 99mTcO4- into cerebrospinal fluid from blood on brain scintigraphy (author's transl).

It is well known that the permeability of the blood brain barrier and blood cerebrospinal fluid barrier changes more or less in various diseases of the central nervous system. At present, thee is no clinically available index which reflects the alteration of the permeability of the blood brain barrier and blood cerebrospinal fluid barrier. The brain scintiraphy is an examination which detects a breakdown in the blood brain barrier, its clinical usefullness is limited only in a localized and extremely pathological proces of the brain. In this report, a cerebrospinala fluid isotope measurement comined with the brain scintigraphy was presented as a clinical examination for blood brain barrier function. Thirty minutes prior to brain scintigraphy, potassium perchlorate (4 mg/kg) was given orally to reduce the accumulation of 99mTc04-in the choroid plexus and to minimize iradiation for tr other organs. Spinal tap was performed two hours after injection of 99mTc04- according to Haines's method...

Adolescent↗