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Biomedical subjects

K Matsui

Publications and source records attributed to K Matsui.

At least 361 records · Page 20Linked to original sources

Enzymatic synthesis of glucoside derivatives of validamine and valienamine.

alpha- And beta-glucoside derivatives of validamine and valienamine were prepared by enzymatic transglucosidation using alpha- and beta-glucosidase of Rhodotorula lactosa. The structures of these derivatives have been elucidated by 13C- and 1H-nuclear magnetic resonance spectral analysis. Thus, 7-alpha-glucoside, 7-alpha-isomaltoside, and 4-alpha-glucoside of validamine and 7-alpha-glucoside, 7-alpha-isomaltoside, 4-alpha-glucoside, and 4-alpha-isomaltoside of valienamine were obtained from maltose and validamine or valienamine using alpha-glucosidase. 7-beta-glucoside, 2-beta-glucoside, and 4-beta-glucoside of validamine or valienamine were obtained from cellobiose and validamine or valienamine using beta-glucosidase. These derivatives were tested for alpha-glucosidase inhibitory activity on rat small intestinal glycosidases.

Animals↗

Preparations of cyclic sulfoxide derivatives and their evaluation as transdermal penetration enhancers.

Novel cyclic sulfoxides, such as 2-octyl, 2-dodecyl and 2-hexadecyltetrahydrothiophene-1-oxide were prepared by the alkylation of tetrahydrothiophene-1-oxide. Additionally, 2-methyl, 2-ethyl and 2-propyl-5-dodecyltetrahydro-thiophene-1-oxide were conducted by further alkylation. Their enhancing activity on the penetration of indomethacin through rabbit skin was evaluated in in vitro experiments, and the effect of the alkyl length on the enhancing activity was discussed. Among the 2-alkyl-tetrahydrothiophene-1-oxides, the compounds containing dodecyl and hexadecyl groups promoted a much greater penetration of the drug through the skin than the compound containing an octyl group. A stronger effect was observed in the experiment using 2-dodecyl-5-alkyltetrahydrothiophene-1-oxide, as compared with the that of 2-dodecyl-tetrahydrothiophene-1-oxide. The substitution of the alkyl groups to the next position of the sulfoxide group seemed to make the enhancing activities large.

Animals↗

[Oxidation of hydrogen sulfide with cell-free extract of Hyphomicrobium neptunium ATCC 15444].

Soluble (Fr. 1) and membrane (Fr. 2) fractions were prepared from the cell-free extract of Hyphomicrobium neptunium ATCC 15444, and their effects on the oxidization of hydrogen sulfide (H2S) were studied. When H2S gas was supplied to Fr. 1 and Fr. 2, sulfur in both fractions and the majority of thiosulfate ion in Fr. 1 were detected. The sulfide-oxidizing activity in Fr. 2 but not in Fr. 1 was inhibited by the addition of diethyldithiocarbamate, suggesting that Fr. 1 and Fr. 2 have different types of sulfide-oxidase, and that Fr. 2 would include cytochrome c dependent sulfide oxidase. It was also found that thiosulfate ion was formed from sulfur and sulfite ion by adding Fr. 1. However, the pronase-treatment of Fr. 1 did not influence on the formation of thiosulfate ion. These results suggest that H2S was oxidized to sulfur and sulfite ion by two types of sulfide oxidase and sulfur oxidase in H. neptunium ATCC 15444, and that the sulfite ion changed rapidly to thiosulfate through a non-enzymatic reaction with sulfur.

Bacteria↗

[Prostate cancer after subcapsular prostatectomy diagnosed as benign prostate hypertrophy--clinico-pathological analysis].

Of 160 newly diagnosed cases of prostate cancer during last 11 years, six (3.75%) had a prior subcapsular prostatectomy. Digital rectal examination in these six cases revealed a significant prostatic abnormality and multiple bone metastases were showed. Histological examination by step-section technique was done retrospectively using surgical materials from subcapsular prostatectomy. Two cases of incidental carcinoma were detected histologically. One showed stage A1 and another stage A2. Continuous observation should be performed after prostatectomy, even if the surgical specimens revealed no carcinoma.

Aged↗

[Prognosis of small cell lung cancer with ipsilateral pleural effusion].

A total of 184 patients with small cell lung cancer (SCLC) including 18 patients with ipsilateral pleural effusion as the only evidence of metastasis beyond the primary tumor site (PL), 84 patients with limited disease (LD), and 82 patients with extensive disease (ED) were treated at the Osaka Prefectural Habikino Hospital between December 1982 and June 1990. The median survival time for patients with PL was 51 weeks; for the patients with LD, 51 weeks; and for the patients with ED, 34 weeks. The survival of PL patients was significantly better than that of ED patients (P less than 0.05), and did not differ from that of LD patients. The response rate of PL patients was not significantly different from the response rates observed in LD- and ED-patients. There was no significant difference in survival or response rate between patients with cytologically positive and those with cytologically negative PL. Ipsilateral pleural effusion was not found to be a independent prognostic factor for survival from multivariate analysis in LD patients. These results indicate that the classification of limited disease small cell lung cancer should include patients with ipsilateral pleural effusion, as suggested by the consensus report at the International Association for the Study of Lung Cancer (IASLC) Workshop in 1989.

Adult↗

[New antitumor antimetabolites--gemcitabine and DMDC].

Gemcitabine (dFdC) and DMDC are new antimetabolites with good antitumor activities against various tumors which include human leukemic cell lines and a number of rodent and human solid tumors and human tumor. They are structurally related to cytarabine (Ara-C) which is known as one of the most effective drugs against adult acute leukemia, but many solid tumors are insensitive not been found to the drug. Gemcitabine acts as an inhibitor of ribonucleoside diphosphate reductase and inhibits DNA synthesis. Biochemically Gemcitabine is rapidly phosphorylated to dFdCTP which has a comparatively longer half-life than that of Ara-C, showing a therapeutic activity against tumors. In the phase I trials, the reported maximum-tolerated doses were 790 mg/m2 to 1370 mg/m2 at the schedule of 30 minutes i.v. infusion once a week for three weeks but higher dose levels (2,500 mg/m2 to 4,800 mg/m2) were reported in the schedule of prolongation of the infusion time. Reported toxicities were myelosuppression, fatigability, fever, appetite loss and skin rash. Toxicities were seemed to be mild. In USA, Europe and South Africa, phase II trials of Gemcitabine at the schedule of 30 minutes infusion once a week for three weeks followed by one week rest were performed against solid tumors (breast cancer, ovarian cancer, renal cancer, colorectal cancer, pancreas cancer, head and neck cancer, and lung cancer) and showed good responses to those tumors. DMDC was developed in Japan, and a phase I trial is currently on-going.

Animals↗

[Feeding problems in severely handicapped children].

Nineteen patients with severely handicapped children were divided into 3 groups; tube-fed patients (group 1, n = 8), oral-fed patients with dysphagia (group 2, n = 3) and oral-fed patients (group 3, n = 8). Clinical symptoms, past history, cranial CT, EEG, blink reflex and auditory brainstem response were evaluated in these patients. All patients of group 1 and 2 could not control head or sit by themselves. They needed naso-oral suction. However, nasal airway, intubation and tracheostomy were necessary only in group 1 patients. Five out of 8 patients of group 3 could control head and sit by themselves. No one needed naso-oral suction. CT revealed ventricular dilatation or prominent destructive lesions in group 1. However, patients of group 2 and 3 showed the lesions of mild to moderate degree. EEGs showed poorly developed background activities or electrical status epilepticus in group 1, while they showed relatively well-developed background activities with less prominent paroxysmal discharges in group 2 and 3. R2 component of blink reflex was absent bilaterally in 90% patients of group 1 and 2, while unilateral R2 at least was present in group 3. Feeding problems in severely handicapped children were affected by combination of cerebrum and brainstem involvements. Examination of cranial CT, EEG and blink reflex was useful to determine the method of feeding.

Adolescent↗

[A case of cardiac arrest encephalopathy in athetotic cerebral palsy].

A 25-year-old woman with cerebral palsy of spastic quadriplegia and athetosis showed typical cardiac arrest encephalopathy on neuropathology. The etiology of cerebral palsy was perinatal origin including prematurity, asphyxia and hyperbilirubinemia. Ventricular premature beats had developed since about 20 years of age. Muscle tone also increased with aging and symptoms of vago-vagal reflex were occasionally observed after eating. At 25 years, cardiac arrest occurred and cardiopulmonary resucitation was done immediately. She remained unconscious with absent corneal reflex and irregular respiration. EEG or auditory brain stem response showed flat activity. She died of respiratory failure 53 days after the episode of cardiac arrest. Neuropathology showed bilaterally symmetrical necrosis in the superior colliculi, gracilis nuclei, cuneate nuclei and spinotrigeminal nuclei accompanied with severe necrosis in the cerebrum and cerebellum. These findings in this adult case of total asphyxia were compatible with those observed in total plus partial asphyxia in the neonates. This discrepancy may be due to difference in cerebral maturity. Children or young adults with athetotic type cerebral palsy have a high risk of sudden death. Sudden cardiac arrest seems to play an important role in sudden death of these patients.

Adult↗

[Effects of open-heart surgery on renal function in patients with chronic renal failure--is hemodialysis during cardiopulmonary bypass really required?].

In 300 consecutive adult patients who underwent open-heart surgery in our department, 16 patients (ischemic heart disease in 8 patients, valvular heart disease in 7 and congenital heart disease in 1) were preoperatively complicated with chronic renal failure (CRF); creatinine clearance (Ccr) < 40 ml/min and serum creatinine (Scr) > 1.6 mg/dl. The effects of open-heart surgery on renal function were studied in these CRF patients who were divided into the following 3 groups according to their preoperative Ccr values: Group 1 (6 patients), 30 < Ccr < 40 ml/min; Group 2 (5 patients), 20 < Ccr < 30 ml/min; and Group 3 (5 patients, 4 of whom were on dialysis preoperatively), Ccr < 10 ml/min. In addition, Group C (38 patients, Ccr > 50 ml/min) was set up as normal controls. Instead of hemodialysis, the extracorporeal ultrafiltration method (ECUM) was employed for all patients during the cardiopulmonary bypass (CPB). The Ccr in Group 1 showed the lowest value of 24.2 +/- 12.0 ml/min on postoperative day (POD) 0 which then recovered to the preoperative level on POD 1. This quick recovery of the Ccr in Group 1 was similar to that in Group C. In contrast, the Ccr in Group 2 showed the lowest value of 13.0 +/- 6.0 ml/min on POD 1, followed by a delayed recovery that did not reach the preoperative level until POD 5. The Ccr in Group 3 was quite low (< 5 ml/min) throughout the test period.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

[An autopsy case of Fahr disease (infantile form)].

A 13-year-old girl with Fahr disease (infantile form) was reported. Her parents were consanguineous. Her elder sister had mental retardation and spasticity of the lower limbs, and died at 23 years of age. The patient suffered from infantile spasms at 3 month. She was bed-ridden, nonverbal, microcephalic and blind. Cranial CT revealed massive calcifications in the basal ganglia, periventricular white matter, dentate nucleus and cerebellar white matter. EEG showed a suppression-burst pattern. At 13 years, she died of pneumonia and hyperammonemia. Microscopic examination of brain showed perivascular non-arteriosclerotic ferro-calcinosis. The periventricular granules are 1-4 mu or 12 mu in diameter. This pathological change was observed only in the central nervous system above midbrain. No calcifications were found in the pituitary and the vessels of pia mater. Also a reduced ornithine transcarbamylase activity was found in the liver, which was probably not related with cerebral calcifications. Infantile form of Fahr disease is rare and may be heterogeneous in etiology. However, clinical manifestations and pathological findings were similar to those in previous reports of Fahr disease in childhood. It is one of the disorders causing infantile spasms.

Adolescent↗

[Prevalence rate of severely mentally and physically handicapped children in school age in Yokohama].

Prevalence rate and pattern of disabilities were studied in severely mentally and physically handicapped children in school age in Yokohama. We visited institutions and schools for retarded children in Yokohama and its neighborhood or made contact with them by telephone. The study disclosed a total of 192 children on May 1, 1988. Prevalence rate was 0.51 per 1,000. Patterns of disabilities were: 1) most of the children (94.8%) lived with their families. 2) eighty-eight percent of the children attended school for retarded children. 3) about twenty percent of the children who attended school needed tube feeding.

Child↗

[Hemodynamic effects of induced hypotension by ketanserin in anesthetized dogs].

Hemodynamic effects of hypotension induced by ketanserin were investigated in 18 mongrel dogs under 0.87% halothane in oxygen (1 MAC). They were randomly allocated to one of two groups. Group C (n = 9) received no vasodilator therapy and served as a control and group K (n = 9) received 0.1% ketanserin solution. Mean arterial pressure decreased and was maintained at 60 mmHg for 60 minutes in group K. No change was noted in hemodynamic variables measured in group C throughout the experiment. During and after induced hypotension in group K, stroke volume index increased significantly compared with the control value. On the other hand, systemic vascular resistance was significantly reduced, reaching 50% of the control value at the end of the hypotensive period. Left ventricular maximum dp/dt showed a significant reduction during hypotension but then increased gradually to the control value. In addition, heart rate decreased significantly during and after induced hypotension, therefore these vasodilator effects were not accompanied by reflex tachycardia. Cardiac index remained unchanged throughout the experiment. Further, no changes in central venous pressure, mean pulmonary artery pressure, pulmonary capillary wedge pressure and pulmonary vascular resistance were observed. In conclusion, the data indicate that ketanserin is a potent systemic vasodilator producing stable hemodynamics. It also reduces systemic vascular resistance without reflex tachycardia and this is a favorable effect of ketanserin.

Animals↗

[Endocrine effects of induced hypotension by ketanserin in anesthetized dogs].

Plasma levels of catecholamines, aldosterone and cortisol as well as plasma renin activity during hypotension by ketanserin were studied in 9 mongrel dogs under 0.87% halothane in oxygen (1MAC). Mean arterial pressure was reduced and maintained at 60 mmHg for 60 minutes by the infusion of 0.1% ketanserin solution. Plasma norepinephrine decreased progressively during hypotension to 35% of the control value after induced hypotension. In contrast, plasma epinephrine increased three-four folds compared with the control value during and after induced hypotension, but this change was not statistically significant. Plasma renin activity and plasma aldosterone showed a slight increase during hypotension but returned toward the control value after discontinuing the infusion of ketanserin. Plasma cortisol remained unchanged throughout the experiment. In conclusion, our data show that hypotension by ketanserin is not accompanied by the activation of the renin-angiotensin-sympathetic system or adrenocortical system.

Animals↗

[Valve repair for mitral regurgitation due to ruptured chordae tendineae--repaired valve function and late results].

Among 21 consecutive patients with significant mitral regurgitation due to ruptured chordae tendineae operated by an author (K.M.) between March, 1980 and August, 1990, the 18 patients who underwent mitral valve repair were studied to assess the repaired valve function and late results of the repair. The chordal rupture was due to idiopathic degenerative disease in 14 patients, infective endocarditis in three and trauma in one. Patients' ages ranged from 35 to 70 years (mean age 52). Nine patients were in New York Heart Association class II and the remaining nine in class III. In three patients with ruptured chordae of the anterior mitral leaflet, reconstruction of the chordae with xenograft pericardium was performed in two patients and partial closure of a commissure in one. In 15 patients with ruptured chordae of the posterior leaflet, Kay's repair was performed in 13 patients and leaflet resection technique in two. In addition to the chordal and leaflet repairs, Kay's mitral annuloplasty was performed in all. There was no hospital death and all patients showed significant hemodynamic improvement (systolic pulmonary arterial pressure from 43 +/- 20 mmHg preoperatively to 24 +/- 4 mmHg postoperatively, and pulmonary arterial wedge pressure from 17 +/- 10 mmHg to 6 +/- 3 mmHg, p less than 0.001 respectively). The repaired valves showed mild pressure gradient of 3.1 +/- 1.2 mmHg which was significantly lower than the gradient of 6.6 +/- 3.5 mmHg of SJM prostheses. Residual murmur was documented in six patients, in three of whom, however, the murmur disappeared within one year following the operation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Low affinity interaction of peptide-MHC complexes with T cell receptors.

The interaction of antigen-specific T cell receptors (TCRs) with their ligands, peptides bound to molecules of the major histocompatibility complex (MHC), is central to most immune responses, yet little is known about its chemical characteristics. The binding to T cells of a labeled monoclonal antibody to the TCR was inhibited by soluble class II MHC heterodimers complexed to different peptides. Inhibition was both peptide- and TCR-specific and of low affinity, with a KD = 4 x 10(-5) to 6 x 10(-5) M, orders of magnitude weaker than comparable antibody-antigen interactions. This finding is consistent with the scanning nature of T cell recognition and suggests that antigen-independent adhesion precedes TCR engagement.

Amino Acid Sequence↗

Establishment of tumor cell lines as an independent prognostic factor for survival time in patients with small-cell lung cancer.

We studied tumor samples from 39 patients, who entered our study from January 1989 to May 1990, to assess whether the ability to establish a continually growing tumor cell line from fresh tumor specimens can be associated with decreased survival times in patients with small-cell lung cancer. The tumor samples were used to establish cell lines in culture using a serum-free medium supplemented with hydrocortisone, insulin, transferrin, estrogen, and selenium (HITES). Thirty-three of these specimens were obtained by fiberoptic bronchoscopy from primary sites during routine diagnostic procedures. A total of 11 (28%) cell lines were established: seven (21%) from 33 primary tumors and four (80%) from five peripheral lymph nodes. Survival times of the 11 patients whose tumor cell specimens continually grew in culture at any time during their clinical course were significantly shorter than those of the 28 patients whose tumor cell specimens did not grow in vitro (median survival time of 26 weeks versus 73 weeks; P = .0068). Cox's proportional hazards model, including sex, age, Eastern Cooperative Oncology Group performance status, stage, source of specimen, treatment, and in vitro tumor cell growth in the overall patient group, showed that cell line establishment (P = .0017) and no therapy (P = .0015) were the most important factors indicating poor survival time. For the subgroup of 23 primary tumor patients, the important factors (in decreasing order) that indicated decreased survival times were the establishment of a cell line (P = .0112) and with cyclophosphamide-doxorubicin-vincristine alternating with cisplatin-etoposide, versus cisplatin-vincristine-doxorubicin-etoposide therapy (P = .0463). Our study demonstrates that in vitro tumor cell growth is an adverse predominant prognostic factor in patients with small-cell lung cancer.

Aged↗