Biomedical subjects

M Minakawa

Publications and source records attributed to M Minakawa.

17 recordsLinked to original sources

PubMed2006

[Emergency small-sized stent placement following aortic true lumen obliteration of Stanford type B acute aortic dissection].

Acute aortic obstruction induced by acute aortic dissection frequently causes life-threatening organ ischemia. Although early reperfusion of lower extremities, renal and mesenteric artery is necessary, surgical treatment such as graft replacement is invasive and may result in myonephropathic-metabolic syndrome (MNMS), which leads to loss of limb and life. We herein report a case of stent placement as a less invasive treatment for true lumen obliteration associated with Stanford type B aortic dissection in a patient with chronic renal failure on hemodialysis. Ten mm metallic stents were placed in the obliterated true lumen of the descending aorta in order to perfuse peripheral organs within 5 hours after occurrence. It relieved symptoms of visceral organ and leg ischemia. On the postoperative day 14, abdominal discomfort after meal, hypertension in the upper extremity and headache appeared. Chest and abdominal computed tomography (CT) revealed stenosis of the true lumen proximal to the stents. On the other hand, the diameter of the true lumen was inversely dilated distal to the stents. Bilateral axillo-femoral artery bypass was performed with relief of upper extremity hypertension and visceral organ ischemia. The patient otherwise had an uneventful course and was discharged on the postoperative day 37. Our experience suggests that emergency stent placement can provide an option that is less invasive, more effective and prompt treatment for patients with visceral organ and leg ischemia resulting from acute aortic dissection.

Aortic Dissection↗

PubMed2003

Hyperthyroidism causes mechanical insufficiency of myocardium with possibly increased SR Ca2+-ATPase activity.

Hyperthyroidism is known to affect multiple organ functions, and thyroid hormone has been known to improve myocardial function in a failing heart. The purpose of this study is to elucidate the functional and metabolic effects of thyroid hormone on myocardium in a rat model exposed to long-term excess thyroid hormone, particularly focusing on the SR Ca(2+)-ATPase (SERCA2) function. 3,5,3'-Triiodo-L-thyronine (T3), or the vehicle, was subcutaneously given for 4 weeks (T3 and control [C] group). Bolus I.V. Thapsigargin (TG) was used to test the SERCA2 function (C-TG and T3-TG) in Langendorff perfused heart. Myocardial functions such as LV-developed pressure (LVDP; mmHg), +/- dP/dt (mmHg/s), tau (ms), and oxygen consumption (MVO(2); ml/min/g wt) were measured. SERCA2 and GLUT4 protein level were also evaluated by Western immunoblotting. Left ventricle to body weight (LV/BW) ratio was significantly higher in the T3 group. Both negative dP/dt and tau were significantly decreased by TG. It is interesting that the decrement of negative dP/dt and tau attained by TG was significantly larger in the hyperthyroid group (T3-TG) than in a normal heart (C-TG). SERCA2 and GLUT4 protein levels were not significantly different between control and the T3 group. We conclude that prolonged exposure to thyroid hormone causes hypertrophy of the myocardium and an augmentation of the SR Ca(2+) ATPase activity. Care must be taken in hyperthyroid heart during the ischemia-reperfusion process where the SRECA2 function is inhibited.

Animals↗

PubMed2003

[Effectiveness and advisability of using a graft in off-pump coronary artery bypass grafting].

In off-pump coronary artery bypass grafting (off-pump CABG: OPCAB) procedures involving multiple vessels, the Aorta No-Touch technique is increasingly being adopted to avoid cerebral infarction, while gastro-epiploic artery (GEA)-left anterior descending coronary artery branch (LAD) anastomosis or composite T-grafting is performed to supply blood to multiple coronary arteries through the left internal thoracic artery (LITA) as an inflow conduit. The objective of the present study is to investigate the effectiveness and advisability of grafting in patients who undergo OPCAB involving multiple vessels, including those who undergo standard CABG. CONCLUSIONS 1: Composite T-grafts of the LITA in OPCAB involving multiple vessels can present certain problems with patency, patient survival, and need for subsequent revision procedures. In the event of a graft failure, serious symptoms resembling left main coronary trunk (LMT) may develop. 2: The incidence of cardiac events with GEA-LAD is high, and patency in the distal phase is poor. 3: Ideally, LITA-LAD should be performed alone. 4: Among patients who have been screened before the procedure, satisfactory results are obtained for OPCAB in which the ascending aorta serves as an inflow conduit; this procedure should be considered as a viable option.

Aged↗

PubMed2001

[Minimally invasive direct coronary artery bypass performed via diaphragmatic approach].

From October 1996 until August 2000, coronary artery bypass grafting (CABG) for right coronary artery was performed via diaphragmatic approach. This procedure was done in 18 patients consist of 13 male and 5 female ranging in age from 47 to 81 years old. Ten of 18 cases were performed coronary bypass reoperation. Right gastroepiploic artery was used in 16 cases, and branched radial artery or saphenous vein graft from gastroduodenal artery was used in one case. Bypassed region in right coronary artery was segment 3 in 9 cases, right posterior descending artery in 8 and right atrio-ventricular branch in one. All grafts were patent in postoperative cardiac catheterization. This approach was desirable for the case, which bypass grafting to right coronary artery is necessary, on account of avoiding injury of patent bypassed graft by median sternotomy in re-do CABG. For the patient whose stomach had been resected, bypass grafting from gastroduodenal artery with radial artery or saphenous vein graft to right coronary artery is useful procedure.

Aged↗

PubMed1999

Saline volume and local anesthetic concentration modify the spread of epidural anesthesia.

PURPOSE: To examine the effects of the volume of saline and the concentration of local anesthetic on the quality of anesthetic level. METHODS: One hundred and fifty two patients received thoracic epidural anesthesia were allocated into two groups; mepivacaine 1% (75 patients) and 1.5% (77 patients). Each group was randomly divided into three subgroups depending on epidural saline volumes of 1 ml, 5 ml, or 10 ml. Fifteen minutes after the injection of 10 ml mepivacaine, the dermatome levels of hypesthesia to cold and pinprick were determined by an individual blinded to the saline volume. RESULTS: The number of spinal segments with hypesthesia to cold in the three subgroups in the mepivacaine 1% group were 12.5 [6-20], 13 [8.5-20.5] and 12.5 [6.5-22], respectively (median [range]). The segments in the mepivacaine 1.5% group were 12 [7-18.5], 14 [8.5-19]* and 15 [6-23]*, respectively (*P < 0.05 vs 1-ml group). The number of spinal segments with hypesthesia for pinprick in the three subgroups in the 1% mepivacaine group were 10.5 [2-22], 10.5 [4-17] and 11 [4-19], respectively. The segments in the mepivacaine 1.5% group were 12 [7.5-16], 12 [7.5-17] and 11.5 [5-22.5], respectively. Saline volume did not alter the anesthetic level of the mepivacaine 1%, although it did affect the anesthetic spread of the mepivacaine 1.5%. In both groups, a differential nerve block was elicited in the 5 ml and 10 ml saline subgroups. CONCLUSION: When a large volume of saline is administered prior to local anesthetic, more differential blockade and a greater extent of anesthesia may be elicited.

Aged↗

PubMed1998

Cerebellar cell lines established from a p53-deficient adult mouse.

p53-Deficient mice are prone to develop spontaneous tumors [L.A. Donehower, M. Harvey, B.L. Slagle, M.J. McArthur, C.A. Montgomery Jr. , J.S. Butel, A. Bradley, Mice deficient for p53 are developmentally normal but susceptible to spontaneous tumors, Nature 356 (1992) 215-221], but brain neoplasms are rare and difficult to culture in vitro. Here we describe cloning and long-term culture of heterogeneous neural cell lines from a multifocal cerebellar neoplasm that arose in an adult p53-/- mutant mouse. These lines may be useful for studies of neoplastic transformation and cell lineage in cerebellar development.

Animals↗

PubMed1997

[A case of mediastinal goiter with hyperthyroidisms].

A 65-years-old woman admitted to the hospital in order to treat of the mediastinal tumor, but she suffered from palpitation, slight fever, sweating, uneasiness, sleeplessness and weightloss. On the physical examination, she was experiencing tachycardia, fevering (37.2 approximately 37.6 degrees C). Skin was moist but had no exophtalmos or neck tumor. Chest X-ray showed an abnormal shadow in the upper mediastinum. On chest CT, a tumor mass (9 x 5 x 4 cm) with cystic regions and scattered calcifications occupied from anterior to posterior mediastinum. The tumor compressed trachea to the left and right brachiocephalic vein and SVC to the right. Lower portion of the tumor intruded into behind of the trachea. Lymph node swelling of mediastinum was also detected. Results of general laboratory examination were within normal limits. Thyroid function test revealed hyperthyroidism; T3U 58%, free T3 24.4 pg/ml, free T4 6.0 ng/dl and thyroglobulin 967 mg/dl, but TSH was < 0.01 microIU/ml. After daily administration of methimazole (300 mg/day) for 4 weeks, thyroid function became to normal level and symptoms of hyperthyroidism was disappeared. The tumor was completely extirpated with right hemithyroidectomy and lymph node dissection under neck colla incision and median sternotomy. Pathological finding of the tumor showed follicular-fetal adenoma of thyroid with hyaloid degeneration and cystic change. There was no finding suspected of Graves' disease. She is well without any complications for 8 months after operation. Some discussion of the literature was mentioned.

Adenoma↗

PubMed1997

[Preoperative evaluation of the right ventricular function using the pulsed Doppler echocardiogram in the patients scheduled for the elective pulmonary resection].

Preoperative evaluation of the both right ventricular (RV) systolic and diastolic function using the pulsed Doppler echocardiogram were examined for 46 patients scheduled for the pulmonary resection of the pulmonary tumorous lesions. The parameters which included the RV inflow pattern at the tricuspid orifice and the RV ejection flow pattern at the RV outflow tract were obtained by the pulsed Doppler echocardiogram. Following results were obtained. 1) The RV afterload shown by the parameters of the acceleration time (AT, time beginning of RV ejection to peak velocity) were higher in the aged patients, the low FEV 1% populations, and the patients having the deteriorated left ventricular contraction. 2) The RV diastolic dysfunction were present preoperatively in aged patients over the 60 years old. This phenomenon was characterized by a high degree of atrial contraction and an increased ratio of the peak velocity in atrial contraction phase to that in early rapid filling phase (A/E). When we evaluate the RV inflow and ejection Doppler flow patterns after the major lung resection, these findings must be considerable thing.

Adolescent↗

PubMed1979