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H Tokunaga

Publications and source records attributed to H Tokunaga.

At least 145 records · Page 8Linked to original sources
PubMed1989

[Time course of blood velocity changes and clinical symptoms related to cerebral vasospasm and prognosis after aneurysmal surgery].

Cerebral vasospasm is a major complication associated with subarachnoid hemorrhage. In spite of extensive research, the pathogenesis of vasospasm remains obscure, and clinical management has so far been extremely difficult. For the evaluation of the efficacy of any treatment and the timing of operation, the development and resolution of the arterial narrowing should be monitored. It is important to know the correlation between the change in flow velocity and the course of clinical symptoms. In this study, the blood flow velocity in the different arteries was measured at short intervals (at least every third day) with transcranial Doppler ultrasonography, in eighteen patients with ruptured cerebral aneurysm. Flow velocity changes began to accelerate from 3 days after surgery, and reached the maximum value between 7 and 10 days, with normalization occurring within the following 2 weeks. The changes showed a significant relationship to the severity of vasospasm, the side of the operative approach, and the administration of calcium antagonist. Based on our results, we categorized the flow velocity changes of vasospasm for clinical practice as follows. (1) A slight acceleration of up to 120 cm/s in MCA and 90 cm/s in ACA was defined as within the normal range. In this state vasospasm was never observed angiographically. (2) Flow velocity changes between 120 and 140 cm/s were a subcritical state. These changes were seen in vasospastic patients who did not develop ischemic deficits. (3) Flow velocity changes of over 140 cm/s in MCA and 100 cm/s in ACA were critical vasospasm, since all of the patients who developed ischemic symptoms were in this group. Velocity changes higher than 170 cm/s in MCA and 130 cm/s in ACA seem to indicate a critical condition with a tendency to develop into brain infarction. The comparison between the time course of the flow velocity changes and clinical status showed that in symptomatic vasospasm the increase in velocity occurred before the manifestation of clinical symptoms. The transcranial Doppler measurements help to identify those patients who have a high risk of developing neurological deficits due to vasospasm, and help to select those who would benefit from preventive treatment in asymptomatic stage.

Adult↗
PubMed1989

Different histochemical findings in the brain produced by mercuric chloride and methyl mercury chloride in rats.

The chemical form of mercury reactive by the histochemical technique was studied by using rats and mice treated with mercuric chloride (HgCl2) and methyl mercury chloride (MeHgCl). Mercury granules were demonstrated histochemically in the brain of HgCl2-treated rats with higher levels of inorganic mercury. However, mercury granules were not demonstrated in the brain of MeHgCl-treated rats in spite of a considerably high organic mercury level. In rats and mice with significant biotransformation of injected MeHg to inorganic mercury, the appearance of the peak inorganic mercury level and mercury granules in the brain seemed to occur on the same day. These results suggested that mercury granules in the brain represent inorganic mercury, but not organic mercury. In the brains showing mercury granules, the lowest level of inorganic mercury was 0.12 micrograms/g in HgCl2-treated rats, 0.14 micrograms/g in MeHgCl-treated rats, and 0.12 micrograms/g in MeHgCl-treated mice. These values were similar to the level of inorganic mercury in the brain from human autopsy cases. Mercury granules were demonstrated histochemically in nerve cells, choroid plexus and phagocytes in the brain of both HgCl2-and MeHgCl-treated rats, and in ependyma of MeHgCl-treated rats. The level of inorganic mercury of the brains showing mercury granules in phagocytes was lower in MeHgCl-treated rats than in HgCl2-treated rats. The numbers of mercury granules in nerve cells increased with the rising level of inorganic mercury in the brain of MeHgCl-treated rats.

Animals↗
PubMed1989

[Evaluation of myocardial protection with DBcAMP in crystalloid cardioplegic solutions].

The potential for myocardial protection during cardiac operation was evaluated by adding Dibutyryl cyclic AMP (DBcAMP) to the crystalloid cardioplegic solutions. We have compared the cold crystalloid cardioplegia with DBcAMP (Group D n = 15) and without DBcAMP (Group n = 20) in patients undergoing cardiac operation. In hemodynamics, both groups were no difference before and after operation. CPK and CPK-MB was significantly (p < 0.01) high level after cardiopulmonary bypass (CPB) in group C. Myoglobin was also high value after CBP in group C, but not significant. Myocardial oxygen extraction rate and coronary blood PCO2 release were similar change in both groups. Insulin/glucose ratio was high level during and after CBP in group D. Myocardial lactate/pyruvate ratio was very high level after CBP in group C without significant difference. We consider that the cardioplegic solution with DBcAMP is effectual for the myocardial metabolism and preservation of myocardial damage during cardiac arrest.

Adult↗
PubMed1988

[Extra-anatomic bypass grafting for vascular occlusive disease in the upper and lower extremities].

Twenty-four patients with poor risk factors underwent an extra-anatomic bypass operation for aortoiliac occlusive disease and subclavian steal syndrome. A femoro-femoral bypass was performed on 5 patients, an axillo-femoral bypass on 15, a subclavian-subclavian bypass on 2 and an ascending aorta-femoral bypass on 2. There was only one operative death and there were 2 late deaths (8.3%). The patients were 20 males and 4 females with a mean age of 69.3 years. Among risk factors, high age (70 year old) was present in half of the patients, ischemic heart disease in 9, and cerebral vascular disease in 8. Seventy-five percent of the patients were suffering from two or more dysfunctions. During the limited follow-up period from 8 to 94 months (mean 46.1 months) there was a 96% patency rate. We had good results using externally supported ring graft and by the administration of prostaglandin E1 and ticlopidine during the pre and postoperative period.

Aged↗
PubMed1988

High glucose-6-phosphatase activity in osteoblasts in the metaphysis of femur of growing rats.

Glucose-6-phosphatase (G6Pase) activity was examined cytochemically in the metaphysis of femurs of 3- and 7-day-old rats. G6Pase and hexokinase activities were also examined biochemically in the femur and tibia of 3-day-old animals. The reaction product for G6Pase activity was seen in the endoplasmic reticulum and nuclear envelope of all cell types composing the metaphysis. The amount of the reaction product was abundant in osteoblasts, moderate in osteocytes, and moderate to scarce in osteoclasts and capillary endothelial cells. Biochemical G6Pase activity in the bones was higher than that in the brain, submandibular gland, or pancreas of the animals. Hexokinase activity in the bones was not different from that in the submandibular gland, pancreas, or kidney. The activity ratio of G6Pase and hexokinase in the bones (0.603) was greater than that in the submandibular gland, pancreas, or brain and smaller than that in the kidney. Possible physiological significances of the higher G6Pase activity in osteoblasts are discussed.

Animals↗
PubMed1988

An isolated aneurysm of the common iliac artery associated with an arterio-venous fistula: autotransfusion technique and postoperative hemodynamic monitoring--a case report.

Isolated aneurysms of the common iliac artery occur less frequently than abdominal aortic aneurysms. Moreover, the rupture of an isolated iliac aneurysm into a systemic vein is considered to be very rare. The case reported herein is of a patient with a left common iliac aneurysm which ruptured into the iliac vein, who was successfully treated surgically, using Doty's autotransfusion technique as a supportive measure. We describe our preoperative diagnosis, operative method, including the supportive measures, and the postoperative hemodynamic changes monitored by a Swan-Ganz catheter.

Aneurysm↗
PubMed1988

[Right aortic arch with isolation of the left subclavian artery. A case report].

A 58 year old man was admitted to evaluate his swallowing disturbance. Preoperative aortogram demonstrated right aortic arch with isolation of left subclavian artery. Operative findings revealed the absent blood flow through the proximal portion of left subclavian artery which connected to the left pulmonary artery. Abnormal connection was divided and Kommerell's diverticulum was mobilized from the esophagus. His clinical symptom was slightly reduced postoperatively.

Aorta, Thoracic↗
PubMed1988

[Autotransplantation of nipple-areolar complex in a modified radical mastectomy--indications and three-stage breast reconstruction].

Necessity of breast reconstruction after mastectomy has been increasing in recent years. For better reconstruction, we preserve a nipple-areolar complex (NAC) by transplanting it temporarily onto the lower abdominal wall and retransplant it to the restored breast mound in a subsequent operation. Indications for NAC preservation are as follows: (1) by palpation the tumor is found to be smaller than 3.0cm in diameter without apparent regional and distant metastasis, (2) neither abnormal nipple discharge nor nipple retraction is observed, (3) tumor is remote more than 3.0cm from the areolar margin, (4) no abnormal shadows are seen below the nipple and areola in the mammogram, (5) no microscopic extension of the cancerous cells is detected beneath the resected NAC. We have performed 18 transplantations using this procedure with good cosmetic results. There were no recurrent cases due to NAC preservation. It is concluded that this technique for preserving the NAC by autotransplantation is easy to perform and useful for breast reconstruction because of low risk of recurrence and better cosmetic results.

Adult↗
PubMed1987

Physiological role of skeletal muscle glycogen in starved mice.

To study the physiological role of skeletal muscle glycogen in starved animals, effects of starvation on glycogen and glycogen phosphorylase (EC 2.4.1.1.) activity were studied in muscle fibers (morphologic study) and in whole muscles (biochemical study) of the rectus femoris muscle of mouse. Glycogen content in the liver of the starved animals was also measured. PAS reaction, strong in muscle fibers of fed animals, became weak predominantly in type IIB fibers after 2 days and almost disappeared after 4 days of starvation. Glycogen particles, numerous in the sarcoplasm between myofibrils of muscle fibers, decreased markedly predominantly in type IIB fibers after 2 days and almost disappeared after 4 days. Phosphorylase a activity, undetected in fibers of fed mice, appeared weak in type IIB fibers and very weak in type IIA fibers after 2 days and became moderate in type IIB fibers and weak in type IIA fibers after 4 days. Muscle glycogen content did not differ by 16 hours from the values of corresponding fed animals. However, liver glycogen content had already decreased after 8 hours and markedly so after 12 hours. The results support our hypothesis-"skeletal muscle glycogen is used for maintaining the blood glucose level in starved mice" (Hirose et al.: Anat. Rec., 216:133-138, 1986)-and show that type IIB fibers play a main role in maintaining the glucose level and that muscle glycogen is utilized after depletion of liver glycogen.

Animals↗
PubMed1987

Significance of increase in glucose 6-phosphatase activity in brown adipose cells of cold-exposed and starved mice.

Cytochemical and biochemical glucose 6-phosphatase (G6Pase) activity was examined in brown adipose tissues of normal, cold-exposed, or starved mice. In addition, G6Pase activity in white adipose tissue and hexokinase activity in brown and white adipose tissues were biochemically measured. In normal animals, the reaction product for G6Pase activity was localized in the endoplasmic reticulum and nuclear envelope of brown adipose cells. The amount of the reaction product increased in cold-exposed or starved animals. Biochemical G6Pase activity (259.7 +/- 48.5 ng Pi/min/mg protein) in brown adipose tissues of normal animals was higher when the value was compared with values of other organs. Biochemical G6Pase and hexokinase activities increased rapidly in brown adipose tissues of cold-exposed animals, and a close relation was found between activities of the two enzymes. In brown adipose tissues of animals starved for 3 days, biochemical G6Pase activity increased, but hexokinase activity did not change. In white adipose tissues of normal, cold-exposed, or starved animals, G6Pase activity was very low, although the enzyme activity increased slightly in animals starved for 3 days. The results show that the high G6Pase activity in brown adipose cells probably relates to thermogenesis in cold-exposed animals and may be concerned with glucose release into the blood in starved animals.

Adipose Tissue, Brown↗
PubMed1987

Glucose 6-phosphatase and glycogen phosphorylase activities in chondrocytes in epiphyseal cartilage of growing rats.

Glycogen, glycogen phosphorylase, and glucose 6-phosphatase (G6Pase) activities were examined cytochemically in chondrocytes of femoral epiphyseal cartilages and cartilaginous ribs of 3- and 7-day-old rats. G6Pase activity was also examined biochemically. Glycogen was abundant in chondrocytes of the reserve zone, while it became scarce in the cells of the proliferative zone. From the upper part (adjoining the proliferative zone) to the lower part of the hypertrophic zone, glycogen accumulated in chondrocytes and decreased in the cells of the degenerative zone. Inversely, glycogen phosphorylase a and G6Pase activities were relatively high in chondrocytes of the proliferative zone and upper hypertrophic zone and were low in the cells of the reserve zone, lower hypertrophic zone, and degenerative zone. The reaction product for G6Pase was present in the endoplasmic reticulum and nuclear envelope of all types of chondrocytes composing the cartilages, although the amounts of reaction product varied with the cell types in parallel with the histochemical results. Biochemical G6Pase activity was higher in epiphyseal cartilages than in cartilaginous ribs. The possible mechanism and significance of the accumulation and decrease of glycogen in chondrocytes of the epiphyseal cartilage were discussed.

Animals↗