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Biomedical subjects

H Kumano

Publications and source records attributed to H Kumano.

At least 73 records · Page 4Linked to original sources

[Evaluation for mitral valvuloplasty using rasping procedure].

From April 1992 through July 1994, 7 patients underwent mitral valvuloplasty using rasping procedure in conjunction with open mitral commissurotomy. All patients had satisfactory postoperative results without the complications such as restenosis, regurgitation, infection. However, thromboembolism was observed in 1 patient at the postoperative 6 months. And no reoperation for repaired mitral valve was observed. Transvalvular pressure gradient significantly decreased from 14.3 +/- 8.5 mmHg to 4.7 +/- 1.6 mmHg after operation. Mitral valve areas significantly increased from 1.01 +/- 0.31 cm2 to 1.78 +/- 0.41 cm2 after operation. As compared with preoperative value of 0.32 +/- 0.02, postoperative left ventricular fractional shortening (LVFS) significantly improved to 0.40 +/- 0.03. The advantages of this method is considered to be equable and safe débridement, and no anticoagulation at late period. Mitral valvuloplasty using rasping procedure, except for transmural calcified lesions, is useful and effective method. And excellent postoperative long-term results could be expected.

Aged↗

Response of pial vessel diameter and regional cerebral blood flow to CO2 during midazolam administration in cats.

Midazolam has been demonstrated to preserve the response of cerebral blood flow to CO2. However, the responsiveness of cerebral vessels or microcirculation during midazolam administration related to alteration of cerebral blood flow has not been explored. The purpose of this study was to examine the effects of midazolam on cerebral microcirculation. Nine cats were paralyzed and mechanically ventilated under nitrous oxide/oxygen anaesthesia. Using the closed cranial window technique and laser Doppler flowmetry, diameter of pial vessels and regional cerebral blood flow (rCBF) were examined on the surface of the cerebral cortex which was perfused by the middle cerebral artery. Before midazolam administration, haemodynamic variables, blood gases, rCBF, and diameter of pial vessels were determined as a control under normocapnia, hypocapnia, and hypercapnia conditions. After midazolam administration, given initially at 0.8 mg.kg-1.min-1 for 10 min and subsequently at 0.04 mg.kg-1.min-1 (total dose 10 mg.kg-1), the same variables were again analyzed. With regard to CO2 responsiveness, an 8.85% increase in rCBF was demonstrated for a Paco2 elevation of 1 kPa before midazolam administration, compared with a 7.47% increase after midazolam administration. With regard to the correlation between CO2 response and vessel diameter, arterioles less than 50 microns in diameter were more sensitive than those more than 50 microns in diameter, although there were no significant differences before or after midazolam administration. We conclude that CO2 responsiveness is preserved in terms of rCBF and vessel diameter after high doses of midazolam (10 mg.kg-1) in cats.

Animals↗

Effects of flumazenil during administration of midazolam on pial vessel diameter and regional cerebral blood flow in cats.

We implanted closed cranial windows in ten cats in order to observe the response of pial vessel diameter by microscopy using fluorescein isothiocyanate-labeled dextran and regional cerebral blood flow (rCBF) by laser Doppler flowmetry during administration of midazolam and reversal with flumazenil. Midazolam was given at 0.8 mg.kg-1 x min-1 for 10 min and maintained at 0.04 mg.kg-1 x min-1 for 50 min (total 10 mg.kg-1). The diameter of arterioles and venules and rCBF showed no significant change. During the last 10 min of midazolam administration, flumazenil, given at 0.1 mg.kg-1 x min-1 for 10 min (total 1 mg.kg-1), caused an increase of MAP and rCBF (P < 0.01) at 5 min after infusion and diameter of larger arterioles (> 50 microns) and venules (50-100 microns) were dilated (P < 0.05). These results indicate that midazolam does not affect the diameter of cerebral arterioles and venules; however, the reversal effects of flumazenil against midazolam are transient vasodilation of larger arterioles accompanied by an elevation of MAP, and an increase in CBF.

Animals↗

[Effects of enflurane, isoflurane, and sevoflurane on renal tubular functions].

Twenty-seven patients without renal disease were divided randomly into three groups of each nine patients. Each group received either enflurane, isoflurane or sevoflurane. The renal tubular functions were examined during anesthesia and on the first postoperative day. By inhalation of 1.49 MAC hours of enflurane, 2.17 MAC hours of isoflurane or 1.29 MAC hours of sevoflurane, creatinine clearance, Na excretion rate, urine beta 2-microglobulin and urine N-acetyl-beta-D-glucosaminidase showed no significant changes during anesthesia and the during postoperative period among anesthetic agents used. These results indicate that enflurane, isoflurane or sevoflurane does not affect renal tubular function specifically under anesthesia when each was given for less than four hours.

Adult↗

Interrelationship between serum muscle enzymes and a low T3 in anorexia nervosa.

To determine the interrelationship between muscle dysfunction and a low T3 state, both seen in anorexia nervosa, we studied the relationship between the degree of muscle involvement, as assessed by the circulating concentration of the three muscle indicators (CPK, GOT and LDH), and serum T3 in thirty-three patients when they were admitted to the hospital. We also studied the malnutritional state, as assessed by their body weight or serum GH, serum potassium and the degree of hyperactivity exhibited. Additionally, another twelve patients were studied in order to explore the mounding phenomenon which is typically elicited in hypothyroidism. The logarithms of serum CPK and GOT correlated only with the serum T3 concentration (r = -0.35, p less than 0.05; r = -0.41, p less than 0.05; respectively). The logarithm of serum LDH highly correlated with serum T3, the percentage of ideal body weight, and the logarithm of serum GH (r = -0.55, p less than 0.01; r = -0.66, p less than 0.001; r = 0.43, p less than 0.05; respectively). The mounding phenomenon was elicited in ten out of twelve patients. In conclusion, it was implied that a low T3 state was associated with an increase in serum muscle indicators and thus with muscle dysfunction encountered in anorexia nervosa.

Adult↗

[Intraoperative anoxic spells in patients with tetralogy of Fallot].

We experienced 5 cases of intraoperative anoxic spell in 48 patients with tetralogy of Fallot (TOF). One of 5 cases had tetralogy with pulmonary atresia (Type A), and the others had tetralogy alone (Type D). The patient of type A who had anoxic spells during preoperative period had been on chronic propranolol therapy. However, the patients of type D had no anoxic spells during preoperative period and one in this type had not been on beta-adrenergic blocking drugs preoperatively. One patient was anesthetized with fentanyl-diazepam-O2, and the others were anesthetized with morphine-diazepam-O2. We used mainly alpha-adrenergic drugs and sodium bicarbonate for the therapy of intraoperative anoxic spells. Concerning the intraoperative anoxic spell, we have to be aware in the management of the patients with TOF, whether the patient had anoxic spells during preoperative period or not.

Adolescent↗

Why are cadaveric renal transplants so hard to find in Japan? An analysis of economic and attitudinal aspects.

In view of the fact that in Japan treatment of end-stage renal disease depends disproportionately heavily on hemodialysis and almost negligible on transplants from cadaveric donors (hemodialysis 44.4/100,000; renal transplants 0.31/100,000 per year; cadaveric renal transplants 0.11/100,000 per year (1983 data)), we analysed the cost-effectiveness of hemodialysis and renal transplantation, predicted economic gains under expected changes in variables and described attitudes of the Japanese hampering cadaveric renal transplantation. Adjusted life expectancy of transplant recipients (live and cadaveric combined) under the current technical conditions is longer than that of those on hemodialysis (18.3 vs. 14.7 years) and the cost per year for maintaining the transplant is approximately one third of hemodialysis ($12,000 vs $32,000). If the proportion of cadaveric transplant recipients would increase to the levels of the USA (hemodialysis 30.8/100,000; transplants 2.6/100,000 per year; cadaveric transplants 1.9/100,000 per year (1983 data)) along with improvement in graft survival rate, the life expectancy for transplant recipients in Japan could increase by 2 years, thus reducing the annual cost even further. The current number of patients starting hemodialysis (11,500 cases per year) coupled with their life expectancy predicts the number of patients on hemodialysis to reach equilibrium at around 174,000 in a decade (Japanese population 110 million). Based on current price, their annual cost will be about 5.3 billion dollars. Medical expenditure of this magnitude for such a small fraction of people is expected to become an increasingly strong economic incentive for cadaveric renal transplantation. A review of studies on Japanese attitudes toward cadaveric renal transplantation in both urban and rural areas shows that approximately 60% are in favor of donating their kidney after death, though with the majority of cases the donation is contingent upon agreement of their family. It was suggested that the paucity of cadaveric kidney supply stems mainly from the custom of the Japanese to make decisions by consensus. It was also reported that more than 80% of physicians supported the donation of cadaveric grafts while this rate fell to 40% in case of brain death. As the first heart transplantation was carried out in 1968 under both medically and ethically dubious circumstances, distrust toward the diagnosis of brain death appears to be still quite strong. (Not a single heart transplantation has been attempted in Japan in the past 18 years).(ABSTRACT TRUNCATED AT 400 WORDS)

Attitude to Health↗

Relationship between trait anxiety, brain activity and natural killer cell activity in cancer patients: a preliminary PET study.

The purpose of this study is to examine the relationship between psychological factors, regional brain activity and natural killer cell activity (NKA). Eight patients with malignant diseases were studied by FDG-PET under a resting condition. NKA and degree of anxiety and depression were measured using Taylor's manifest anxiety scale (MAS) and Zung's self-rating depression scale (SDS). Linear correlation of NKA and psychological measures to the regional brain metabolism in cancer patients was examined using statistical parametric mapping (SPM). Positive linear correlation between NKA and regional metabolic rate ratios was identified in the visual association cortex, anterior cingulate gyrus (CG) and sensorimotor area, and negative correlation was identified in the inferolateral prefrontal cortex (ILPFC), prefrontal cortex (PFC), orbitofrontal cortex (OFC) and anterior temporal cortex. Positive linear correlation to the MAS score was identified in the visual association cortex, anterior CG, primary sensorimotor area and the posterior parietal cortex, and negative correlation was detected in the ILPFC, PFC, OFC and anterior temporal cortex. The NKA and MAS scores positively correlated with each other (p<0.001). The result might serve as supporting data for a hypothesis that psycho-immune interaction is also mediated by the cerebral cortex and limbic system.

Adult↗

Clinical effects of blood pressure biofeedback treatment on hypertension by auto-shaping.

OBJECTIVE: Although biofeedback has been reported to be efficacious in the treatment of hypertension, the degree of response has varied. This study investigated the mechanisms of blood pressure reduction by biofeedback. METHOD: Thirty outpatients with essential hypertension (10 men and 20 women) aged 38 to 65 years were studied. Subjects were randomly assigned to group A or B. Subjects in group A underwent biofeedback treatment once a week for a total of four sessions. Those in group B self-monitored their blood pressure during the sessions as the control period and later underwent the same biofeedback treatment. RESULTS: Blood pressure measured by doctor was reduced by 17 +/- 18/8 +/- 7 (p < .01) and elevation of pressure induced by mental stress testing was suppressed by 8 +/- 9 (p < .05)/4 +/- 8 during the treatment period in group A (mm Hg). In group B, both blood pressure measured by doctor and elevation of pressure by mental stress testing remained unchanged during the control period and they were later suppressed by 20 +/- 15/9 +/- 7 (p < .01) and 11 +/- 10(p < .05)/5 +/- 9 by the biofeedback treatment. Self-monitored pressure in both groups tended to decrease by the biofeedback treatment. Systolic and diastolic pressures as well as pulse rate decreased, skin temperature increased, and alpha-wave amplitude on electroencephalography increased during the therapy (p < .05). CONCLUSION: This treatment was effective in suppressing the pressor response to stress. Patients whose blood pressure increases with stress may be suited for biofeedback intervention.

Adult↗