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Biomedical subjects

K Matsui

Publications and source records attributed to K Matsui.

At least 397 records · Page 22Linked to original sources

All eight possible mono-beta-D-glucosides of validoxylamine A. II. Biological activities.

The biological activities of all eight possible mono-beta-D-glucosides of validoxylamine A against Rhizoctonia solani were studied. The attachment of the D-glucosyl residue to validoxylamine A generally diminished the inhibitory activity against trehalase. The introduction of the D-glucosyl residue at the C-3 position did not cause serious loss in activity, while substitution at the C-6' position caused complete loss in trehalase inhibitory activity. Of the eight beta-D-glucosides, 4-O-beta-D-glucopyranosylvalidoxylamine A (4-O-beta-Glc-VA), 3-O-beta-Glc-VA and 5'-O-beta-Glc-VA exhibited very strong activity against R. solani in the "dendroid-test method". The antagonistic activity of sugars (1 mM) against validoxylamine A and 4-O-beta-Glc-VA was examined using the "dendroid-test method". The inhibitory effect of validoxylamine A on hyphal extension was not antagonized by any sugars tested, whereas that of 4-O-beta-Glc-VA was antagonized by beta-1,3- and beta-1,4-glucooligosaccharides. Of 2-O-, 3-O-, 4-O- and 7-O-beta-Glc-VAs, 7-O-beta-Glc-VA exhibiting the lowest activity was not antagonized by any beta-glucooligosaccharides tested. The inhibitory effect of 3-O- and 4-O-beta-Glc-VAs was antagonized by most beta-glucooligosaccharides. The uptake of 4-O-beta-Glc-VA into the mycelia was inhibited by laminaribiose and cellobiose but not by maltose.

Antifungal Agents↗

Specificity of protective immunity induced by porin from Salmonella typhimurium.

The specificity of protective immunity against Salmonella typhimurium in mice immunized with porins from S. typhimurium, Salmonella enteritidis and Escherichia coli was studied. High levels of protection against S. typhimurium-infection were achieved in mice immunized with porins from S. typhimurium but not from S. enteritidis and E. coli. However, our serological studies demonstrated that porins from S. typhimurium, S. enteritidis and E. coli had antigenic cross-reactivity with each another; in particular, porins immunized with porins from S. typhimurium but not from S. enteritidis or E. coli exhibited the most significant levels of delayed type hypersensitivity reaction, interleukin-2 production and interferon-gamma production when they were elicited with whole cells of S. typhimurium. These observations suggested that the high levels of protection obtained by porin-immunization resulted from the induction of serovar specific cell-mediated immunity.

Animals↗

[The significance of CA-50, SLX and ST-439 in lung cancer].

Serum levels of CA-50, SLX and ST-439 were measured in 213 patients with lung cancer (92 adenocarcinomas, 63 squamous cell carcinomas, 37 small cell carcinomas and 21 large cell carcinomas) and 87 patients with benign lung disease. The overall positive rates in patients with lung cancer were 12.8% for CA-50, 29.7% for SLX and 25.3% for ST-439. The positive rates for CA-50, SLX and ST-439 in adenocarcinoma patients were 22.8%, 42.4% and 38.0%, respectively. Of the patients with benign lung disease, 4.8% were false positive for CA-50, 15.3% for SLX and 3.6% for ST-439. In the patients with adenocarcinoma of the lung, the combination assay of CEA and ST-439 had a highly accurate rate (61.9%).

Adenocarcinoma↗

Small cell carcinoma of the stomach: a clinicopathologic study of 17 cases.

Of 17 cases of small cell carcinoma of the stomach, three were early and 14 were advanced. Grossly, the tumors were mostly polypoid at the early stage, and as they advanced, deep ulcerations developed. Histologically, only one tumor was "oat cell type," and the other 16 were "intermediate cell type." With regard to tumor components, five were "pure" tumor, and 12 were "composite" admixing glandular and/or squamous differentiation. Argyrophil cells were seen in eight tumors. Immunohistochemically positive cells for chromogranin, neuron-specific enolase, and keratin were seen in 12, 10, and 7 tumors, respectively. Carcinoembryonic antigen was negative in the small cell component of most tumors as opposed to strong positivity in the glandular component. Electron-dense core granules were evident in seven of nine tumors examined. These findings suggest that histologic variety is quite characteristic of the small cell carcinomas of the stomach, and this type of carcinoma takes an aggressive clinical course like its counterparts in other organs.

Adenocarcinoma↗

[Endocrine effects of hypotension induced by diltiazem in rabbits].

Endocrine effects of hypotension induced by diltiazem, a calcium antagonist, were studied in 16 male rabbits under the inhalation of 0.7% halothane in oxygen. They were randomly allocated to one of two groups. Group C (n = 8) received no vasodilator therapy and served as control and group D (n = 8) received infusion of diltiazem. Mean arterial pressure was decreased and was maintained at 60 mmHg for 60 minutes in group D. No change was noted in plasma catecholamines measured in group C throughout the experiment but plasma renin activity decreased progressively. During and after induced hypotension in group D plasma epinephrine showed a dramatic rise compared with the control value. The maximum increase occurred 30 minutes after induction of hypotension but this change was not statistically significant. Plasma norepinephrine in group D was significantly higher than the control value. Compared with the control value (0.19 +/- 0.04 ng.ml-1), plasma norepinephrine was activated 30 and 60 minutes after induction of hypotension (0.71 +/- 0.16 ng.ml-1, P less than 0.05, 0.82 +/- 0.20 ng.ml-1, P less than 0.05, respectively). Plasma renin activity in group D was significantly higher than the control value. The highest level of plasma renin activity was three times the control value 30 minutes after induction of hypotension. In conclusion, our data show that induced hypotension by diltiazem activates the renin-angiotensin-sympathetic nervous system.

Animals↗

Effect of phosphoenolpyruvate on energy metabolism of ischemic liver in anesthetized rats--31P-MRS study.

The effect of phosphoenolpyruvate (PEP) on energy metabolism of ischemic liver was examined in anesthetized rats. In vivo 31P-NMR spectroscopy (31P-MRS) was used to monitor cellular energy metabolism. Hepatic ischemia was induced by temporarily clamping the portal vein for 60 minutes. The liver adenosine triphosphate (ATP) levels decreased remarkably during ischemia, and they gradually increased after ischemia but did not return to pre-operative levels. PEP effectively increased the levels of ATP. The ATP levels of the PEP-treated rats were significantly higher than those of the control rats, and also intracellular acidosis was improved during post-ischemic reperfusion. These findings suggest that PEP may have a cytoprotective effect and improve the energy metabolism in the ischemic liver.

Adenosine Triphosphate↗

A randomized trial comparing imipenem/cilastatine alone with latamoxef plus tobramycin in febrile neutropenic patients with lung cancer.

We conducted a randomized trial to compare the efficacy of imipenem/cilastatine (IPM/CS) monotherapy with that of a combination of latamoxef (LMOX) and tobramycin (TOB) in the initial management of fever and neutropenia in patients with lung cancer. Leukocytopenic febrile patients (less than 3,000 leukocytes per microliters; temperature greater than 38 degrees C) with lung cancer given induction therapy were randomly assigned to receive intravenous treatment with either 1 g IPM/CS twice daily or 2 g LMOX plus 90 mg TOB twice daily. A total 101 febrile episodes were studied. Fifty-one episodes were treated with IPM/CS and 50 with LMOX+TOB. Fifty-nine of the febrile episodes were bacteriologically confirmed, while an organism could not be isolated despite the presence of obvious clinical infection in the remaining 42. The response rate was 82% with IPM/CS and 80% with combination therapy. This difference was not statistically significant. The response rate regarding gram-negative infections was 10 out of 14 (71%) in the IPM/CS group and seven out of 12 (58%) in the LMOX+TOB group. This difference was also not significant (P = 0.484). The response rate in severely neutropenic patients (neutrophils less than 100/microliters) was low (P = 0.078). Three patients in the IPM/CS group were withdrawn from the study due to skin rash and vomiting. Therapy with IPM/CS monotherapy was as effective as a combination regimen.

Adult↗

Preparation of alkyl-substituted pyrrolidone derivatives and their evaluation as transdermal penetration enhancers.

The preparation of novel transdermal penetration enhancers derived from 2-pyrrolidone were carried out, and the enhancing activities of drug permeation through the skin were evaluated by means of in vitro experiment. All the enhancers contain a short alkyl group, such as methyl, ethyl, propyl or butyl group, at 1-position and a dodecyl group at 3-position of 2-pyrrolidone ring. The enhancing activities were considerably influenced by the length of the short alkyl group at 1-position. 1-Propyl and 1-butyl-3-dodecyl-2-pyrrolidone showed the effective enhancement of penetration of indomethacin through the skin in 60 wt% ethanolic aqueous solution. Moreover, the similar enhancing activities of these compounds were also observed even in ethanolic vehicle.

Administration, Cutaneous↗

Preparations of phosphonate, phosphoramidate and phosphate derivatives and their evaluation as transdermal penetration enhancers.

Phosphonate, phosphoramidate and phosphate derivatives containing long alkyl groups were prepared, and their activities enhancing drug penetration through the skin were evaluated by means of in vitro experiments. The effect of chemical structure of these compounds on enhancing activity was investigated. Among the phosphonate and phosphoramidate derivatives, compounds having a hexadecyl group showed the most effective enhancement of transdermal penetration of indomethacin. For the phosphate derivatives, the enhancing activities were almost equal in the compounds containing dodecyl, tetradecyl and hexadecyl group. All the compounds having an octyl group were not effective in penetration enhancement. Diethyl hexadecylphosphonate and diethyl hexadecylphosphoramidate brought about the highest enhancing activities among these compounds, and the permeability coefficient of indomethacin was about 10-fold as much as that without enhancer. The relationship between the enhancing activities and the lipophilicities of these compounds was discussed.

Administration, Cutaneous↗

[The problems of valproate therapy in severely handicapped children--valproate induced hyperammonemia and hypocarnitinemia].

Blood ammonia and serum free carnitine were measured in 49 severely handicapped epileptic patients treated with or without valproate. DL- or L-carnitine were administered to patients treated with valproate, and the effects of carnitine supplementation were evaluated. Furthermore we analyzed the relationship between serum free carnitine and nutrition. In patients treated with valproate, blood ammonia statistically increased, and serum free carnitine concentration statistically decreased. Free carnitine was low in tube-fed patients, as compared with that in oral-fed patients. Carnitine therapy was successful in improvement of hyperammonemia and hypocarnitinemia. It is concluded that hypocarnitinemia was caused not only by valproate therapy, but also by tube-feeding. Carnitine supplementation therapy is important to both hyperammonemia and hypocarnitinemia. But the long term effect of carnitine therapy remains to be studied further.

Adolescent↗

[Coronary reperfusion using an extracorporeal circulating system performed in cases with abruptly obliterated coronary arteries: a new method].

For the cases with the abruptly obliterated coronary artery during angioplasty or angiography, emergency bypass surgery is mandatory. However, a "bail-out" perfusion catheter with multiple side-holes, which maintains antegrade coronary flow, is not efficient in preventing the myocardium from developing ischemia, because blood flow is interfered due to pressure-dependent perfusion mechanism in the shock state. We developed a new perfusion catheter coupled with an extracorporeal circulating system and a perfusion pump. Its effectiveness and safety were tested experimentally in canine hearts. The system is composed of a perfusion catheter (125 cm in length) with 4 side-holes within 1.5 cm of the catheter tip, and a rolar pump. Maximum flow volumes were 123 ml/min, 84 ml/min, and 52 ml/min for 4.5F, 4.3F, and 4F perfusion catheters, respectively. The left anterior descending coronary artery (LAD) was ligated after the perfusion catheter was advanced into the proximal LAD under fluoroscopic control. To avoid formation of pericatheter intracoronary thrombi, 50 U/kg/hr heparin was continuously injected during a 5-hour ligation. In the nonperfusion group (n = 4), the ST segments elevated in all dogs; 2 died of ventricular fibrillation within 30 min, and one was confirmed to have myocardial necrosis by NBT staining. In the perfusion group (n = 4), neither ECG changes nor hemodynamic deterioration was observed. Intracoronary thrombi were not observed in any surviving dogs. Coronary perfusion using our new device was performed in 2 patients: one patient, a 73-year-old man with 99% stenosis in the very proximal portion of his LAD, had massive intimal dissection after PTCA, and angiography revealed total occlusion of his proximal LAD and LCX. Coronary perfusion was immediately initiated by advancing the perfusion catheter into his LAD. After that the patient recovered from shock. Emergency bypass surgery was successfully performed after 120 min coronary perfusion with the support of IABP and inotropics. The other patient, a 58-year-old man with effort angina, had intimal dissection in the proximal portion of his right coronary artery, which was supplying collaterals to the mid LAD and LCX. Successful bypass surgery was performed 320 min after the coronary perfusion without IABP and inotropics. In conclusion, coronary reperfusion with an extracorporeal circulating system proved to have a greater effect than did passive perfusion in such cases with cardiogenic shock.

Aged↗

Effects of several volatile anesthetics on the Ca(2+)-related functions of skinned skeletal muscle fibers from the guinea pig.

The effects of various volatile anesthetics on intramuscular Ca(2+)-related functions were studied with the skinned fiber technique in guinea pig skeletal muscles. All the volatile anesthetics tested significantly enhanced Ca(2+)-induced Ca2+ release (CICR) from the sarcoplasmic reticulum (SR) at clinical concentrations with negligible effects both on Ca2+ sensitivity of the contractile system and on Ca2+ uptake by the SR. A comparison was made of the enhancing effect of several volatile anesthetics on CICR at clinical concentrations. Halothane was the most potent, followed by methoxyflurane, isoflurane, enflurane, sevoflurane and diethyl ether. If CICR plays an important role in triggering MH, this order of volatile anesthetics on their enhancing effect on CICR, also corresponds to their potency in triggering MH.

Anesthetics↗

[Mortality patterns of children with epilepsies in a children's medical center].

Two hundred and thirty-seven children have died who were seen in the Division of Neurology, Kanagawa Children's Medical Center from 1975 to 1989. They corresponded to about 11% of the total death in the hospital. A total of 128 cases of 237 deaths (54.0%) were suffering from epilepsies, most of whom were also complicated with other CNS disorders. The causes of death were pneumonia, respiratory failure and suffocation in 60%, whereas status epilepticus or convulsions only in 14%. About 40% of victims died at home or in an emergency room without effective resuscitation. Mortality was considered high in infantile spasms (16 out of 146, 11%) and in severe myoclonic epilepsy in infancy (4 out of 8, 50%). It was note worthy that 3 cases of severe myoclonic epilepsy in infancy died of status epilepticus and 2 died at home. Sixteen cases whose chief problems were partial epilepsies and severe myoclonic epilepsy in infancy, died of status epilepticus in 10 cases, convulsions after tonsillectomy, etc. Causes of death of these 16 cases were related to convulsions except in two cases whose causes were pneumonia in one and unknown in the other. About a half of them (7 cases) died at home. Adequate managements appeared necessary to prevent accidental deaths of children with epilepsies.

Cause of Death↗

[Four cases of Cockayne syndrome].

The evaluation of four patients with Cockayne syndrome (CS) by computed tomography (CT) and magnetic resonance imaging (MRI) is reported. All patients had characteristic clinical manifestations of CS. In a special respect, we found hyperopia in two patients and previous habitual abortions in two maternal histories. Extrapyramidal signs were seen in one patient. Three patients are type 1 CS (case 1, 3, 4) and one patient (case 2) is type 2 CS (congenital form). The cranial CT in two patients (case 1, 2) revealed prominent calcifications in basal ganglia, dentate nucleus and hemispheric white matter. While CT showed vagal calcifications in basal ganglia in other two patients (case 3, 4), T2-weighted MRI revealed obvious low intensity area in putamen and caudate nucleus, and high intensity area in the white matter. Sagittal section revealed atrophic changes of cerebellar vermis and brain stem. Thus it seems that MRI may be useful diagnostic adjunct in CS patients.

Brain↗

[Hemodynamic effects of endothelin in anesthetized dogs].

The purpose of the present study was to investigate and compare the hemodynamic responses that can be elicited in anesthetized dogs by intravenous administration of endothelin at rates of 300 (group E-I, n = 9) and 600 pmol.kg-1 (group E-II, n = 9) for 15 minutes. In group E-I, no significant pressure response was observed after administration of endothelin and cardiac index remained unchanged throughout the experiment. However, right and left ventricular work indices increased significantly but left ventricular maximum dp/dt and pulmonary vascular resistance decreased significantly. In group E-II, mean arterial pressure increased significantly by elevating systemic vascular resistance with marked decrease in cardiac index. However, right and left ventricular work indices remained unchanged throughout the experiment. On the other hand, each dose of endothelin significantly increased pulmonary capillary wedge pressure and left ventricular end-diastolic pressure but decreased heart rate. The present data revealed that the hemodynamic effects were different according to the doses of endothelin infused. In conclusion, our results show that endothelin (600 pmol.kg-1 BW) produces a long lasting increase in arterial pressure and endothelin-induced pressure responses are caused by an elevation in systemic vascular resistance.

Anesthesia, General↗

[A case of renal failure due to primary cholesterol atheroembolism].

We report a patient presenting rapid deterioration of renal function due to primary cholesterol atheroembolism. The patient was 75-year-old hypertensive male and was admitted to a hospital because of rt. hemiplegia which developed 2 weeks earlier. On admission, his blood pressure was 200/100 mmHg and serum creatinine level was 2.9 mg/dl with urinalysis 1+ both for protein and hematuria. 2 weeks later, an angiotensin converting enzyme inhibitor (ACE inhibitor, delapril 15 mg/day) was given to control high blood pressure. Immediately after this medication, his renal failure rapidly progressed with a fall in blood pressure (110/60 mmHg) and oliguria (100 ml/day). Although he was transferred to our hospital and was treated with hemodialysis, he died of an attack of acute myocardial infarction in a week. At post-mortem examination, microscopic findings of the kidney disclosed numerous occlusions of medium-sized artery by cholesterol emboli. These emboli were also observed in other organs, but not so prominent as in the kidney. The coronary arteries exhibited severe sclerosis. In this presented case, acute deterioration of renal function was caused by ACE-inhibitor, although which was administered in a volume depleted condition. Therefore, further study would be necessary whether or not ACE-inhibitors predispose the patients with this disease to acute renal failure.

Acute Kidney Injury↗

[Permanent cardiac pacing in patients on chronic dialysis].

Four patients on chronic dialysis, who underwent permanent pacemaker implantation, were reviewed. The indication for pacing was sick sinus syndrome in three patients and complete atrioventricular block in one. Physiological pacing modes were chosen in all patients (DDD in three and AAI in one). Sensing and pacing properties in these patients studied at implantation and at follow-up (22-41 months after implantation) were similar as those in non-dialysis patients. However, the study of these properties during hemodialysis showed a significant elevation of atrial pacing threshold associated with marked decrease of serum potassium concentration in two patients. We conclude that dialysis patients with significant bradyarrhythmia should be considered for pacemaker implantation in the same manner as non-dialysis patients. However, special attention should be payed on the elevation of pacing threshold during hemodialysis.

Aged↗