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Biomedical subjects

H Ogata

Publications and source records attributed to H Ogata.

At least 199 records · Page 11Linked to original sources
PubMed1996

Decomposition kinetics of cisplatin in human biological fluids.

Cisplatin is metabolized to high- and low-molecular mass complexes by exchanging of one or both chloride ligands with nucleophilic species. The decomposition of cisplatin and the formation of its metabolites in human biological fluids was investigated in-vitro. In nucleophile-free medium, cisplatin was decomposed by a reversible chloride ligand exchange reaction, which was dependent upon both chloride ion concentration and medium pH. The effect of pH was observed in the second-order rate constant for cisplatin re-formation, which was far smaller in neutral and alkaline media than in acidic media. In the medium containing nucleophilic species (glutathione, human albumin and globulin), cisplatin was irreversibly decomposed according to apparent first-order kinetics. The linear relationship between apparent decomposition rate constant and concentration of nucleophilic species suggested that nucleophilic species in biological fluids might react with cisplatin directly. Both high- and low-molecular mass metabolites were formed in human plasma and ascites; however, only a low-molecular mass metabolite was produced in urine. The faster decomposition of cisplatin and the greater ratio of fixed and mobile metabolites formed in plasma were mainly attributed to higher albumin concentration in plasma than in ascites and urine. The in-vitro decomposition of unchanged cisplatin and formation of high- and low-molecular mass metabolites in human biological fluids were simultaneously evaluated according to the kinetic model which combined both pathways via hydrolysis and by the direct reaction process with nucleophilic species.

Antineoplastic Agents↗
PubMed1996

No effect of high-protein food on the stereoselective bioavailability and pharmacokinetics of verapamil.

The effects of high-protein food on the bioavailability of both the racemate and individual enantiomers of verapamil were investigated in 12 healthy volunteers using a randomized crossover design. Food had no effect on any parameter of bioavailability for both the racemate and the individual enantiomers of verapamil except time to maximum concentration (tmax), which was significantly prolonged after food intake. The pharmacokinetics of the enantiomers of norverapamil were not significantly changed by food intake. These results suggest that high-protein food does not alter the pharmacokinetics and bioavailability of either the racemate or the individual enantiomers of verapamil. Therefore, the clinical efficacy of verapamil is not related to food intake, except for a slight prolongation in the time to onset of the pharmacologic effects. The present data can be applied to the high-protein content meal intake.

Administration, Oral↗
PubMed1996

Dermatofibrosarcoma protuberans. CT findings with pathologic correlation in 6 cases.

PURPOSE: To characterize the CT findings of dermatofibrosarcoma protuberans. MATERIAL AND METHODS: CT and pathologic specimens of 6 patients with dermatofibrosarcoma protuberans (5 in the trunk and 1 in the leg) were retrospectively reviewed. RESULTS: CT clearly defined the tumors in the dermis and subcutaneous tissue with a characteristic, if not pathognomonic, protrusion. On postcontrast CT, 3 tumors showed marginal enhancement and central low density, while the others showed homogeneous enhancement. Pathologically, the marginal enhancement on CT corresponded to fibrosarcomatous changes, and the central low density to necrosis. The tumors with homogeneous enhancement had no sarcomatous changes. CONCLUSION: CT allows detection and precise anatomic localization of dermatofibrosarcoma protuberans. Marginal enhancement with central low density on CT may suggest a relatively poor prognosis.

Adult↗
PubMed1996

Renovascular hypertension with massive proteinuria.

A 65-year-old woman with renovascular hypertension and massive proteinuria is reported. Her urinary protein ranged from 3 to 5 g/day. Serum potassium was 2.9 mEq/l. Plasma renin activity and plasma aldosterone concentration were very high. A CT scan disclosed atrophy of the left kidney. Renogram showed a non-functioning pattern of the left kidney. An abdominal aortogram showed complete occlusion of the left renal artery at its ostium. After left nephrectomy, her high blood pressure and urinary protein were normalized. It seemed that the massive proteinuria was mainly due to some endocrinological effect of the left kidney.

Aged↗
PubMed1996

Clinical presentation of pulmonary tuberculosis associated with acquired immunodeficiency syndrome in metropolitan Tokyo.

The clinical features of pulmonary tuberculosis associated with acquired immunodeficiency syndrome (AIDS) in Japan were surveyed utilizing questionnaires completed by 48 institutes around the Tokyo metropolitan area. We found 11 Japanese and six foreign patients. The average number of patients per institute was 0.37. The Japanese patients had advanced human immunodeficiency virus (HIV) infection. A middle aged man, with fever and cough, nonspecific chest X-ray infiltrates, decreased lymphocyte counts, and a negative tuberculin skin test was the typical presentation of the Japanese patients. The clinical diagnosis was often difficult. The smear positive rate was high among those from whom smears were obtained, suggesting high communicability. None of the isolates indicated multidrug-resistant tuberculosis at the time of diagnosis. In conclusion, sputum smear and culture remain the keys to diagnosing tuberculosis in patients with AIDS, although the clinical picture may be atypical for pulmonary tuberculosis.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Measuring activities of daily living among haemophiliacs.

To explore the activities of daily living (ADL) status and/or changes in functional limitations among haemophiliacs, 97 patients were studied longitudinally using a 41-item checklist. The total number of data items was 239 with repeated inquiries. Hierarchical factor analyses yielded a clear separation of items into five factors by the analogous trunk and limb motion, and the existence of one higher-order factor which indicated that the items measured the same underlying concept. Analyses of ratings showed that in haemophiliacs full flexion of the lower limbs was easily limited, and this deterioration was difficult to prevent. The functional limitation level differed significantly by age group, but some patients showed a slight improvement in a follow-up observation. The ADL of haemophiliacs should be explored separately for trunk and limb motion, not for the traditional categories.

Activities of Daily Living↗
PubMed1996

[Use of a laryngeal mask airway for anesthesia in a patient with bronchomalacia].

A 56-year-old woman with bronchomalacia underwent three consecutive operations for bronchoscopy, cautery YAG-laser, and the insertion of a stent under general anesthesia using a laryngeal mask airway (LMA). For the first operation, anesthesia was induced with ketamine 20 mg, diazepam 5 mg and pentazocine 20 mg. The patient was ventilated with N2O-O2-sevoflurane with a face mask. Then vecuronium 6 mg was administered intravenously and LMA was inserted blindly. Anesthesia was maintained with N2O-O2-sevoflurane during bronchoscopy. Immediately after the operation, the patient coughed and experienced dyspnea. The symptoms were alleviated using theophyllin, hydrocortisone and droperidol. For the second and third operations, anesthesia was induced with droperidol and fentanyl with N2O-O2. After administration of vecuronium, LMA was inserted. The patient was stable during the second and third operations compared with the first operation. It was concluded that LMA may be useful for anesthetic management of a patient with bronchomalacia.

Anesthesia, General↗
PubMed1996

Cerebral oxygen metabolism measured by near-infrared laser spectroscopy during laparoscopic cholecystectomy with CO2 insufflation.

To clarify the influence of carbon dioxide (CO2) on cerebral oxygen metabolism and blood volume during laparoscopy with CO2 insufflation in 12 patients who underwent laparoscopic cholecystectomy, changes in the concentrations of cerebral oxyhemoglobin (HbO2), reduced hemoglobin (HbR), total hemoglobin (total Hb), and oxidized cytochrome aa3 (Cyt aa3) were measured using near-infrared laser spectroscopy. Anesthesia was maintained with nitrous oxide (66%)-oxygen-sevoflurane. Pneumoperitoneum was maintained at an endoabdominal pressure of 10 to 12 mm Hg using CO2. Minute ventilation was constant before and after CO2 insufflation. End-tidal CO2 tension (PETCO2) increased significantly, from 33.9 +/- 1.3 to 52.8 +/- 3.3 mm Hg, after CO2 insufflation. The concentration of HbO2 increased significantly, from 0 to 7.3 +/- 2.8 mumol/L, after CO2 insufflation. The concentration of HbR increased significantly, from 0 to 2.2 +/- 1.2 mumol/L, after CO2 insufflation. Therefore, the concentration of total Hb increased significantly, from 0 to 8.8 +/- 3.3 mumol/L after CO2 insufflation. The concentration of Cyt aa3, however, did not change significantly during pneumoperitoneum. These results suggest that cellular respiration remained intact despite a concomitant increase in PETCO2 and cerebral blood volume during laparoscopy with CO2 insufflation.

Adult↗
PubMed1996

[II. multidisciplinary analysis of chronic excretors of Mycobacterium tuberculosis bacilli].

For the most patients with pulmonary tuberculosis, treatment are successful and the chemotherapy can be finished within a year. Few patients, though receiving standard anti-tuberculous chemotherapy, expectorate tubercle bacilli continuously for more than a year. They are named "chronic excretors of mycobacterium tuberculosis bacilli" or "intractable tuberculosis patients". Being suspected that this phenomenon is produced by many factors, it is necessary to correspond suitably to these patients for eradication of tuberculosis. This symposium was organized to search for some factors on the bacterium and on the host, which caused patients to be the chronic excretors or intractable patients. We hope that our discussion may contribute to take the appropriate measures for such hard diseases. The main results are summarized as follows. 1) Dr. TSUCHIYA conducted a epidemiologic study by questionaire method to 33 Japanese national sanatoriums. The total number of tuberculosis patients admitted to these hospitals on a optimal day from September to October 1994 were 1,295. Numbers of patients who had expectorated bacilli continuously for more than 12 months were 85 (6.6%). The male/female ratio was about 3, their average age was 64. They had a tendency of thin-physique and most of them had past histories of tuberculosis, being the refractory cases. The average clinico-epidemiologic conditions of the patients came before our eyes. 2) Dr. OGATA analysed the results of drug sensitivity tests of mycobacterium tuberculosis bacilli from 2,630 pulmonary tuberculosis patients which contained 179 chronic excretors. The only 2.2% of bacilli from the chronic excretors were sensitive to RFP (50 gamma). The 99.4% of bacilli showed to be resistant to INH (0.1 gamma). The 39.1% of bacilli were sensitive to streptomycin (20 gamma). To EB (2.5 gamma) 34.1% of bacilli were sensitive. However, the ratio of chronic excretors in tuberculosis patients was not increased in these 17 years, and for many cases of these chronic excretors, they are all inexperienced in PZA, multi-sensitive-drug chemotherapy including PZA and OFLX were useful. Some of them underwent lobectomy combined for effective chemotherapy. The chronic excretors are likely to be affected multidrug-resistant bacilli, and it is important for such cases to treat intensively with several kinds of sensitive drugs. 3) Dr. FUJIWARA studied Interleukin-10 (IL-10) producing function of monocytes stimulated by Mycobacterium tuberculosis (M-TB). The IL-10 usually down-regulates a number of different macrophage functions, including microbicidal activity against intracellular bacteria such as Mycobacterium species. They found that the mean IL-10 production by peripheral blood mononuclear cells (PBMC) obtained from a healthy tuberculin-reactor stimulated with multidrug-resistant M-TB was greater than that with drug-sensitive M-TB. The IL-10 producing cells were monocytes, not T-lymphocytes. They moreover found that PBMC from intractable tuberculosis patients secreted greater amounts of IL-10 than those of healthy subjects. These data may give a hint for development of new immunotherapeutic methods for multi-drug-resistant tuberculosis patients. 4) Dr. HARA analysed clinical courses of 580 consecutive cases of bacilli positive pulmonary tuberculosis admitted in his hospital from a point of underlying diseases. All of dead 24 cases had some underlying diseases; diabetes mellitus 3, chronic liver diseases 4, others 17 (malignant neoplasms, central nerve vascular diseases, malnutritional condition, etc). (ABSTRACT TRUNCATED)

Chronic Disease↗
PubMed1996

[From the views of bacteriology--focusing on drug susceptibility test].

Totally 2630 culture positive pulmonary tuberculosis cases were admitted in our hospital during 17 years from 1976 to 1992. Clinical and bacteriology status of this cases were compered retrospectively between 3 groups; 1938 cases with initial treatment, 513 cases with retreatment excluding chronic tubercle bacilli excreters (CTBEs) and 179 chronic tubercle bacilli excreters. Mean age of the groups of CTBEs is 50.9 years. Sex ratio of it is 4.3:1. These figures are similar to those of the group of the cases with retreatment. Mean age of these groups is higher than 45 years in group of cases with initial treatment. Sex ratio in these group is higher than 3.1:1 in group of cases with initial treatment. Proportion of cases with complication of DM in group of CTBEs is 16.1%, statistically significantly higher than 10% in group of cases with initial treatment and 9% in group of cases with retreatment. Most CTBEs show resistant to both INH and RFP in drug susceptibility test if 0.1 gamma is adopted as clinical concentration of resistance to INH. 40% of CTBEs show susceptibility to SM and 35% of CTBEs show susceptibility to EB in the test. However in a large proportion of these cases with susceptibility result in each of these drugs, more than 34% in SM and more than 40% in EB, effect of the drugs was not observed clinically. Therefore previous treatment history as well as the result of drug susceptibility test should be considered in choice of anti-tuberculosis drug for treatment of CTBEs.

Adolescent↗
PubMed1996

[Cerebral blood volume, cerebral hemoglobin and cytochrome AA3 during hypotension induced by prostaglandin E1 or epidural anesthesia under general anesthesia].

The effect of hypotension induced by PGE1 or epidural anesthesia under general anesthesia on cerebral blood volume (CBV), cerebral tissue hemoglobin, cytochrome AA3 was studied using a near infrared spectrophotometry in 20 patients undergoing abdominal operation. In PGE1 group (n = 10), CBV, cerebral oxyhemoglobin (HbO2) and deoxyhemoglobin (Hb) were unchanged during hypotension. However, cerebral HbO2 decreased and Hb increased slightly in a case of severe hypotension more than 40 percent of control, but CBV did not show any significant change. On the other hand, in epidural anesthesia group, HbO2 decreased significantly along with MAP reduction (r = 0.84) and Hb increased slightly. Cytochrome AA3 did not show any significant changes in both groups. From these results, we concluded that PGE1 drip infusion was better than epidural anesthesia to sustain the cerebral blood volume during hypotension.

Adult↗
PubMed1996

[Hemophagocytosis in a child with paroxysmal cold hemoglobinuria].

A 2-year and 5-month-old boy was admitted to Okaya municipal hospital because of low grade fever and reddish-brown urine soon after an outside walk in November, 1994. Direct Coombs test was negative, but indirect Coombs test positive. Both sugar water test and Ham test were negative. A diagnosis of paroxysmal cold hemoglobinuria (PCH) was made by Donath-Landsteiner (D-L) test which showed the presence of a high amount of anti-P specific IgG and IgM of D-L antibody. Serological tests for syphilis were negative. Cold agglutinin titer and mycoplasma antibody titer was X 128 and X 80, respectively. A bone marrow specimen exhibited pronounced hemophagocytosis. Serum INF-gamma and M-CSF level were normal (less than 5 pg/ml and 1007 units/ml, respectively). These results suggest that hemophagocytosis in this case is not due to hemophagocytic syndrome.

Bone Marrow↗
PubMed1996

[Influence of nitric oxide on superoxide anion radical generation in vivo].

We studied the effect of NO on superoxide anion radical (O2-) generation using chemiluminescence method by examining influence of NO gas on superoxide radical generation in rat lung induced by paraquat (PQ) on CLA-phenyl hybrid paper filters. SD rats were allocated into four groups. Group 1 received i.v. injection of physiological saline as a control group; Group 2 received 70 mg x kg-1 of PQ i.v.; Group 3 received 50,000 unit x kg-1 of SOD i.v., 1, 2, and 3 hours after i.v. PQ administration. Group 4 inhaled 50 ppm NO gas after i.v. injection of PQ. Three hours after administration of each drug in respective group, the right lower lobe of the lung was removed and immediately immersed into liquid nitrogen and then was sliced in width of 20 microns at -20 degrees C using cryostat. The results were summarized as representing overall level of superoxide radicals in each lung sample. PQ increased O2- production by 48% in comparison with the control. However, SOD and NO gas decreased O2- production significantly approximately up to the control level. These results confirmed that NO depresses O2- production in vivo.

Administration, Inhalation↗
PubMed1996

Solitary malignant schwannoma of the lower extremity-a case report.

A case of solitary malignant schwannoma, appearing as a painless mass near the right ankle of a 46-year-old female, is presented. Solitary malignant schwannoma without neurofibromatosis is considered to be quite rare. However, this disorder has a better prognosis than neurofibromatosis. Previous reports indicate that the treatment usually chosen is wide local excision without lymph node dissection, unless clinically involved nodes are present.

Female↗
PubMed1995

Assessment of autonomic function in myotonic dystrophy by spectral analysis of heart-rate variability.

We analyzed by means of autoregressive spectral analysis the spontaneous beat-to-beat heart-rate variability (HRV) of 10 myotonic dystrophy (MD) patients (4 men and 6 women, aged 37-53 years) and 10 age- and sex-matched healthy, sedentary humans (control) at rest in the supine position. All MD patients had no cardiac conduction disturbances (i.e., atrioventricular or intraventricular conduction defects) on 12-lead electrocardiogram and were able to walk and perform daily activities. In the MD group, the total power, the power of the low-frequency component (a marker of sympathetic and vagal modulation of heart rate) and that of the high-frequency component (a marker of vagal modulation of heart rate) were smaller than those in the control group (P < 0.01, P < 0.05 and P < 0.05, respectively). The results of this study suggest that the cardiovascular autonomic nervous system contributing to the HRV may be disturbed even in the MD patients who can walk and perform daily activities. Therefore, one must give careful consideration to the cardiovascular autonomic dysfunction, as well as the cardiac conduction disturbance in the MD patients.

Adult↗