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Biomedical subjects

Y Minami

Publications and source records attributed to Y Minami.

At least 307 records · Page 17Linked to original sources
PubMed1983

GLC-mass fragmentographic determination of mannitol and sorbitol in plasma.

A GLC-mass fragmentographic method was developed for the simultaneous determination of mannitol and sorbitol as their n-butyldiboronate derivatives in plasma. The plasma sample was deproteinized, and the subsequent supernatant was concentrated to dryness; the resulting residue was then dissolved in pyridine containing n-butylboronic acid to allow derivation. An aliquot of this solution was injected into the gas chromatograph-mass spectrometer and analyzed by a selected-ion monitoring method using galactitol as the internal standard. Detection was limited to 20 ng/0.1 ml of plasma for both mannitol and sorbitol. A rapid, precise, and sensitive assay for the determination of mannitol and sorbitol in plasma was established.

Chromatography, Gas↗
PubMed1983

Bundling of microtubules in vitro by a high molecular weight protein prepared from the squid axon.

A high molecular weight protein has been partially purified from sheaths of squid giant axons. This protein fraction was capable of restoring the membrane excitability of the squid axon which had been destroyed by internal perfusion of microtubule poison, when perfused along with microtubule proteins (Matsumoto et al. (1979) J. Biochem. 86, 1155-1158). This protein, designated as 260 K protein, was purified by gel filtration and Con A-Sepharose affinity chromatography. The apparent molecular weight of the axonal protein was estimated to be 260,000 by electrophoresis in the presence of sodium dodecylsulfate. This protein was revealed to be a glycoprotein. When phosphocellulose-purified tubulin was incubated with 260 K protein at 36 degrees C in the presence of dimethylsulfoxide, turbidity of the solution was much increased. 260 K protein co-sedimented with microtubles assembled from purified tubulin. Light microscopic and electron microscopic observations revealed that the high turbidity was due to bundling of microtubules which was caused by 260 K protein. On the other hand, the effect of this protein on the turbidity increase was not so prominent when microtubules were assembled from microtubule proteins consisting of tubulin and microtubule-associated proteins. High shear and low shear viscometry and co-sedimentation experiments revealed that 260 K protein had little effect on actin polymerization under the same medium conditions as used in tubulin polymerization.

Amino Acids↗
PubMed1983

Network formation by neurofilament-induced polymerization of tubulin: 200K subunit of neurofilament triplet promotes nucleation of tubulin polymerization and enhances microtubule assembly.

The previous paper (Minami, Y., et al. (1982) J. Biochem. 92, 889-898) demonstrated that the neurofilament preparation obtained from porcine brain promotes tubulin polymerization, thereby leading to network formation in vitro. Since this preparation fractionated by gel filtration and centrifugation was contaminated mainly by tubulin, the neurofilaments thus prepared were solubilized in a 6 M urea solution, further purified by hydroxyapatite column chromatography, and reconstituted into neurofilaments. This highly purified neurofilament was found to retain the ability to stimulate microtubule assembly and to cause gelation. Next we separated the purified neurofilament into the individual triplet subunits, referred to as 200K, 150K, and 70K proteins, by DEAE-cellulose (DE-52) column chromatography in the presence of 6 M urea. By measuring viscosity and turbidity changes, it has been found that the activity to stimulate polymerization of tubulin is due to the 200K polypeptide, while the 150K protein was less active to promote tubulin polymerization and the 70K protein was totally inactive.

Animals↗
PubMed1983

"Nonalcoholic steatohepatitis" induced by massive doses of synthetic estrogen.

We have noticed that functional disorders of the liver characterized by hepatomegaly and an increase in serum gamma-glutamyl transpeptidase develop in patients with prostatic cancer who are placed under longterm therapy with massive doses of estrogen after castration. We performed laparoscopy in six cases of prostatic cancer with hepatomegaly so that we could study the morphology of the liver. Our findings were as follows. In five, the histological features of the liver biopsies were very similar to those seen in alcoholic hepatitis. In spite of this fact, two of the five had no history of alcohol consumption. Furthermore, in one other case, liver damage resembling alcoholic hepatitis developed during abstinence. The findings in these three cases suggested that long-term, massive doses of synthetic estrogen may lead to liver injury similar to alcoholic hepatitis in nonalcoholics. The ultrastructural findings of the liver cells were also suggestive of the adverse effect of treatment. All cases were negative for hepatitis B surface antigen. Recent reports have demonstrated some nonalcoholics with histological features of the liver indicative of alcoholic hepatitis. This particular condition was termed "nonalcoholic steatohepatitis" by Ludwig et al. It is quite likely that synthetic estrogen is also responsible for "nonalcoholic steatohepatitis" when it is used in massive doses.

Aged↗
PubMed1982

High-performance liquid chromatographic determination of proglumide in plasma.

A rapid and sensitive method for determining the anticholinergic agent, proglumide, in plasma by high-performance liquid chromatography is described. Samples were acidified with hydrochloric acid and extracted with chloroform. The dried extract was resolved in chloroform and chromatographed on an adsorption chromatographic column using a mobile phase of chloroform-methanol (24:1) on a high-performance liquid chromatograph equipped with a UV absorbance detector (240 nm). The detection limit for proglumide was 0.05 microgram/ml.

Chromatography, High Pressure Liquid↗
PubMed1982

Laparoscopic findings of the liver in the diagnosis of primary biliary cirrhosis: "reddish patch", a laparoscopic feature in the asymptomatic stage.

The laparoscopic findings of the livers of 12 patients with primary biliary cirrhosis (PBC), including six asymptomatic and six symptomatic cases, were investigated. On the liver surface of asymptomatic PBC, we found a laparoscopic appearance, consisting of reddish patches of irregular shape, ranging from 0.5 to 3 cm in diameter, and not evenly distributed. Five of six cases of asymptomatic PBC had reddish patches in our series. From serial laparoscopic observations, the patches were found to lose some of their reddish tone and to develop protuberances with vaguely outlined white markings in each reddish areas. The protuberances and white markings are characteristic appearances of the liver surface in more advanced PBC cases. The transition of reddish patches to protuberances with white markings coincided with progression among histopathological stages in PBC classified by Scheuer. A histometrical examination showed that areas with reddish patches had less advanced changes of intrahepatic bile ducts. As a result, we propose that laparoscopic findings of the liver have a value in the diagnosis of PBC and "reddish patch" is considered a laparoscopic feature which has no been described in asymptomatic PBC.

Adult↗
PubMed1982

Interaction of tubulin with neurofilaments: formation of networks by neurofilament-dependent tubulin polymerization.

Interaction between porcine brain tubulin and neurofilaments was investigated with reference to network formation in vitro. When a mixture of tubulin and neurofilaments was incubated at 33--34 degrees C, its low-shear viscosity measured with a falling ball viscometer, was far above the sum of viscosities of the separate components and gelation was observed upon increasing the concentrations of both tubulin and neurofilaments above a certain level. Gelation that required Mg2+ and GTP was inhibited by Ca2+,Ca2+-calmodulin or ATP. Antimitotic drugs suppressed gelation at substoichiometric concentrations and cold treatment destroyed the formed gel, which indicated that gelation occurred in conjunction with tubulin polymerization. Assaying by centrifugation revealed that the amount of tubulin co-sedimented with neurofilaments was evidently larger in the presence of neurofilaments than in their absence. Furthermore, electron micrographs showed that a large number of microtubules which were shorter than usual were formed in the presence of neurofilaments. Interestingly, measurements with an Ostwald-type viscometer demonstrated that neurofilaments elevated the viscosity of the tubulin solution in a concentration-dependent fashion. In other words, neurofilaments had the ability to stimulate polymerization of tubulin. We conclude that polymerization of tubulin with neurofilaments produces three-dimensional networks in vitro.

Animals↗
PubMed1982

A thrombotic tendency in patients with infective endocarditis.

An attempt was made to evaluate a thrombotic tendency in cases of infective endocarditis (IE) from the viewpoint of the changes of platelets and coagulo-fibrinolysis. Qualitative changes of platelets by thrombi formation were detected by showing activated responses of platelets to adenosine diphosphate or collagen and by showing a high level of plasma beta-thromboglobulin which is released by platelets during aggregation. A mild hypercoagulable state without acceleration of fibrinolysis was also detected by showing low levels of plasma antithrombin III which is the most potent antithrombin in the blood and normal levels of plasma alpha 2-plasmin inhibitor in the blood. From above findings, it was concluded that a thrombotic tendency in cases of IE was clearly detected by qualitative changes of platelets by thrombi formation and by mild hypercoagulability without acceleration of fibrinolysis.

Adenosine Diphosphate↗
PubMed1982

[Experimental and clinical studies on ceftizoxime in the field of oral surgery (author's transl)].

Experimental and clinical studies on ceftizoxime (CZX), a new cephalosporin derivative, were carried out and the following results were obtained. 1. The minimal inhibitory concentrations of CZX, cefazolin (CEZ), cephalothin (CET), cefotiam (CTM) and cefmetazole (CMZ) against Gram-positive cocci (31 strains) and Gram-negative rods (169 strains) isolated from the patients with oral infections were determined. CZX, though somewhat less active against Gram-positive cocci than the other cephalosporins, was the most active of the antibiotics tested against Gram-negative rods. 2. The mean serum levels in 19 patients who received 1 g of CZX by intravenous drip infusion for 1 hour were as follows. 19.6 micrograms/ml 30 minutes after the start of intravenous drip infusion, 52.2 micrograms/ml after 1 hour, 25.0 micrograms/ml after 1.5 hours, 20.3 micrograms/ml after 2 hours, 7.9 micrograms/ml after 4 hours, 3.5 micrograms/ml after 6 hours. The mean peak tissue levels of CZX after 1 g dose by intravenous drip infusion for 1 hour were 14.3 micrograms/g (n = 5) in gingiva and 8.5 micrograms/g (n = 2) in bone marrow at the end of intravenous drip infusion. 3. CZX was administered to 17 patients with various infections in the oral surgical field at daily dose of 1 approximately 2 g for 3 approximately 6 days. The therapeutic effect was as follows: 'excellent' in 6 cases, 'good' in 9, 'fair' in 1 and 'poor' in 1. The final rate of effectiveness was 88.2%. No adverse reaction was observed except for 2 cases of slight elevation of S-GPT.

Adult↗
PubMed1982

[Fundamental and clinical studies of cefotiam in the field of oral surgery].

Cefotiam (CTM) is a new synthetic cephem antibiotic developed in Japan. The results of the fundamental and clinical studies are as follows. 1. CTM showed antibacterial activity, in terms of MIC, as strong as those of cephalothin (CET) and cefazolin (CEZ) for Gram-positive cocci, and several times superior to for Gram-negative bacilli. 2. CTM serum levels approximately reached the peaks on completion of 60 minutes intravenous drip infusion of 1 g of this preparation dissolved in 5% glucose solution of 250 ml; the mean value was 65.00 micrograms/ml. Then the levels dropped rather quickly up to 180 minutes after the start of drip infusion. After that, the levels dropped gradually up to 360 minutes. 3. As for the passage of CTM in the oral tissues, satisfactory passage was observed in both maxillomandibular marrow and gingiva, which adequately exceeded MICs of the clinically isolated strains of oral infections. 4. This preparation was administered 1 g of 2 g daily by intravenous drip infusion in 18 cases of moderate or more serious infections in the field of oral surgery; the clinical efficacy rate obtained was 94.4%. 5. No manifestations of side effect were observed clinically. As for laboratory findings, 1 case of large increases in GOT and GTP (a hepatitis B antigen positive patient) and 2 cases of slight increase in GTP were observed. On the basis of these results of the fundamental and clinical studies, it was concluded that CTM is an excellent antibiotic for the treatment of oral infections.

Adolescent↗
PubMed1982

[Experimental and clinical studies of cefmetazole in the field of oral surgery].

Experimental and clinical studies were carried out on cefmetazole (CMZ), a synthetic antibiotic of cephamycin group, and the following results were obtained. 1) The minimal inhibitory concentrations (MICs) of CMZ against Gram positive cocci (30 strains) isolated from the patients with oral infections showed slightly inferior to those of ABPC, CEZ, while MICs against Gram negative bacilli (166 strains) of CMZ exhibited stronger activity than ABPC, CEZ. 2) The mean serum concentration of CMZ at 60 minutes after drip infusion showed 65.6 micrograms/ml. The concentration of CMZ in oral tissues varied in 4--60% of serum level at 60 minutes after drip infusion. The concentration in pus showed 15.2 micrograms/g at 60 minutes after drip infusion. 3) CMZ was administered by the drip infusion to 22 patients with various infections in the oral surgical field. The efficacy rate was 90.9%. 4) No side effect was observed.

Adult↗