Search PubMed⌕ Search

Biomedical subjects

M Miki

Publications and source records attributed to M Miki.

At least 271 records · Page 15Linked to original sources
PubMed1979

Possible correlation between induction modes of hepatic enzymes by PCBs and their toxicity in rats.

Acute toxicity of individual PCBs, which were categorized as either phenobarbital (PB)- or 3-methylcholanthrene (MC)-type inducers, was examined in young male Wistar rats, comparing their effects on growth rate, organ weight and liver lipid content, 5 days after a single i.p. injection. PB-type PCBs (2,4,3',4'- and 2,5,2'5'-tetrachlorobiphenyl), which slightly increased a content of cytochrome P450, did not show any significant toxicity at a dose of 100 mg/kg. On the contrary, MC-type PCBs (3,4,5,3',4'-pentachloro- and 3,4,5,3',4',5'-hexachlorobiphenyl), which markedly increased a content of cytochrome P448, strongly reduced growth rate and weights of thymus and spleen at a dose of 10 mg/kg. Liver enlargement accompanied by fatty liver was also observed only with MC-type PCBs. 3,4,3',4'-Tetrachlorobiphenyl was also toxic at a dose of 50 mg/kg, in keeping with its weak MC-type-inducing ability. Pretreatment with MC affected neither growth rate, spleen weight, nor liver lipid content. These results suggest that the toxic potency of PCBs is related to their MC-type inducing ability, but the toxic characteristics are different from those of MC itself.

Animals↗
PubMed1979

Conformation change in reconstituted thin filament studied with fluorescence energy transfer between epsilon-ADP bound to F-actin and NBD-Cl bound to troponin-C.

The interaction of troponin and F-actin was studied by the methods of fluorescence energy transfer. We used epsilon-ADP bound to F-actin as a fluorescence donor and 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole bound to troponin-C in troponin as a fluorescence acceptor. The efficiency of the fluorescence energy transfer of this system was larger in the absence of calcium ion than in the presence of calcium ion. This shows that the interaction of troponin with F-actin changes in response to the concentration of calcium ion.

4-Chloro-7-nitrobenzofurazan↗
PubMed1978

Fluorescence energy transfer between epsilon-ATP at the nucleotide binding site and N-(4-dimethylamino-3,5-dinitrophenyl)-maleimide at Cys-373 of G-actin.

The method of fluorescence energy transfer is used to measure the distance from the nucleotide binding site to Cys-373 of G-actin. The fluorescent ATP analogue 1-N6-ethenoadenosine 5'-triphosphate was used as donor and N-(4-dimethylamino-3,5-dinitrophenyl)-maleimide was used as acceptor. From the measurements of the efficiency of fluorescence energy transfer by both static and time resolved fluorometries, the distance between nucleotide binding site and Cys-373 residue of G-actin was calculated to be about 30 A.

Actins↗
PubMed1978

Operative nephroscopy with fiberoptic scope: preliminary report.

New fiberoptic scopes, originally designed for biliary tract operations, were used in 23 cases for removal of residual calculi at pyelolithotomy and for examination of the renal pelvis and ureter. The external diameters of the scopes are 6.6 mm. (CHF-X1) and 4.5 mm. (CHF-X2). Water irrigation and forceps manipulation can be performed simultaneously with the CHF-X1 scope but only irrigation can be done with the CHF-X2 scope. The scopes were reliable and allowed easy endoscopic forceps manipulation. Improvements for an ideal fibroptic nephroscope are discussed.

Aged↗
PubMed1978

Labelled gelfoam in transcatheter arterial embolization of renal cell carcinoma.

Six patients with renal cell carcinoma underwent transcatheter arterial embolization with Gelfoam labelled by metallic clips. The embolization procedure was more easily monitored by fluoroscopy, and the complication of peripheral embolization was prevented. Tumor regression can be evaluated by changes in the distribution of the metallic clips on plain films.

Adenocarcinoma↗
PubMed1978

Long-term results of retinal detachment surgery.

Patients treated successfully with retinal detachment surgery 11-39 years earlier were called back and examined. The average age was 35 years at the time of surgery and the average interval between the operation and this follow-up examination was 16 years. The visual acuity had decreased in many patients. The most frequent causes of this fall in visual acuity after surgery were cataract and macular degeneration. Chorioretinal atrophy with blackish pigment spots developed in the reattached retina a long time after surgery and caused defects in the visual fields. This atrophy seems to be related to the long duration of retinal detachment before and after operation, which may cause malnutrition of the detached retina and result in incomplete recovery of visual cells, leading to chorioretinal atrophy. Macular degeneration was caused or accelerated by detachment of the macula. There was no difference in postoperative ocular findings between only diathermy and combination of diathermy with segmental scleral-buckling procedures. However, Arruga's ring suture method induced cataract more frequently than did other surgical procedures.

Adolescent↗