1.CHANGES IN SARCOPLASMIC RETICULUM Ca2+-SEQUESTERING CAPACITY DURING RECOVERY FOLLOWING HIGH-INTENSITY EXERCISE
TAKAAKI MISHIMA ; TAKASHI YAMADA ; MAKOTO SAKAMOTO ; MASANOBU WADA
Japanese Journal of Physical Fitness and Sports Medicine 2006;55(5):503-512
The purpose of this study was to investigate changes in sarcoplasmic reticulum (SR) Ca2+-sequestering capacity in rat fast-twitch plantaris (PL) and slow-twitch soleus (SOL) muscles during recovery after high-intensity exercise. The rats were subjected to treadmill runs to exhaustion at the intensity (10% incline at 50 m/min) estimated to require 100% of maximal O2 consumption. The muscles were excised immediately after exercise, and 15, 30 and 60 min after exercise. Acute high-intensity exercise evoked a 27 % and 38 % depression (P<0.05) in SR Ca2+-uptake rate in the PL and SOL, respectively. In the PL, uptake rate remained lower (P<0.05) at 30 min of recovery but recovered 60 min after exercise. These alterations were paralleled by those of SR Ca2+-ATPase activity. On the other hand, SR Ca2+-uptake rate in the SOL recovered 15 min after exercise. Unlike the PL, discordant time-course changes between SR Ca2+-ATPase activity and uptake occurred in the SOL during recovery. SR Ca2+-ATPase activities were unaltered with exercise and elevated (P<0.05) by 25, 30 and 30% at 15, 30 and 60 min of recovery, respectively. These results demonstrate that SR Ca2+-sequestering ability is restored faster in slow-twitch than in fast-twitch muscle during recovery periods following a single bout of high-intensity exercise and suggest that the rapid restoration of SR Ca2+-sequestering ability in slow-twitch muscle could contribute to inhibition of disturbances in contractile and structural properties that are known to occur with raised myoplasmic Ca2+ concentrations.
2.Effect of moxibustion on hypophysectomized rat.
Makoto MURAI ; Mayumi YAMAUCHI ; Hatsue ASAOKA ; Takako KASAHARA ; Kozi SAKAMOTO
Journal of the Japan Society of Acupuncture and Moxibustion 1987;37(1):24-29
The effect of moxibustion on the endocrinosis elicited by disorders of the autonomic nervous system was investigated in hypophysectomized rat.
Natural gain of body weight was stopped, adrenals and testis became atrophied, urinary output increased, and the rectal temperature slightly dropped after hypophysectomy.
Applying moxibustion did not correct these synptoms.
Furthermore, in spite of electrolyte and amino acid metabolism, significant decrease of Na, K, Cl, Ca and a slight decrease of urea nitrogen and creatinine in urine was recognized. But these were not modify by moxibustion.
With respect to the adrenal cortical study, there were a slight increase of 17-OHCS and a mild decrease of 17-KS in urine. Moxibustion did not effect either 17-OHCS or 17-KS.
3.Juzentaihoto (TJ-48) may be An Important and Effective Anti-Inflammatory Agent for Intractable Cases of Patients with HCV-associated Chronic Liver Diseases
Kazuo TARAO ; Yasunari SAKAMOTO ; Makoto UENO ; Kaoru MIYAKAWA ; Shinichi OKAWA
Kampo Medicine 2010;61(1):1-8
Although glycyrrhizin (SNMC), and ursodeoxycholic acid (UDCA), alone or in combination have been administered in patients with active HCV-associated chronic hepatitis (HCV-CH) or liver cirrhosis (HCV-LC), there are many patients who do not respond well to these anti-inflammatory treatments. In this study, we examined retrospectively the possibility for juzentaihoto to alleviate inflammation in such patients. We calculated average ALT levels every 6 months for all 67 patients. If we assume an improvement in average serum ALT levels of more than 25% after juzentaihoto administration to be significantly effective, as compared with average ALT levels before juzentaihoto administration, 23 out of 40 patients (57.5%) showed significant improvement within one year. In the 32 patients with HCV-associated liver disease who were treated with combination SNMC and UDCA therapy, and whose average ALT levels did not decline to less than 80 IU/L, 18 (56.3%) showed significant improvement when juzentaihoto was added. Juzentaihoto was effective in 62.5% of patients with CH, and 54.2% of those with LC. Moreover, juzentaihoto was effective in 41.2% of male, and 69.6% of female patients. And in about 40% of patients, average ALT levels lowered increasingly over time, out to 2 years. Juzentaihoto may be an effective anti-inflammatory agent for intractable cases of active HCV-CH, or HCV-LC.
4.RELATIONSHIP BETWEEN OXIDATION OF MYOFIBRILLAR PROTEINS AND CONTRACTILE PROPERTIES IN SOLEUS MUSCLES FROM HYPERTHYROID RAT
TAKASHI YAMADA ; TAKAAKI MISHIMA ; MAKOTO SAKAMOTO ; MINAKO SUGIYAMA ; SATOSHI MATSUNAGA ; MASANOBU WADA
Japanese Journal of Physical Fitness and Sports Medicine 2007;56(5):473-480
We tested the hypothesis that a force reduction in soleus muscles from hyperthyroid rats would be associated with oxidative modification of myofibrillar proteins. Daily injection of thyroid hormone [3, 5, 3’-triiodo-L-thyronine (T3)] for 21 days depressed isometric forces in whole soleus muscle across a range of stimulus frequencies (1, 10, 20, 40, 75 and 100 Hz) (P<0.05). In fiber bundles, hyperthyroidism also led to pronounced reductions (P<0.05) in both K+- and 4-chloro-m-cresol-induced contracture forces. The degrees of the reductions were similar between these two contractures. These reductions in force production were accompanied by a remarkable increment (103% ; P<0.05) in carbonyl groups comprised in myofibrillar proteins. In additional experiments, we have also tested the efficacy of carvedilol, a non-selective β1-β2-blocker that possesses anti-oxidative properties. Treatment with carvedilol prevented T3-induced oxidation of myofibrillar proteins. However, carvedilol did not improve the hyperthyroid-induced reductions in force production. These data suggest that oxidative modification of myofibrillar proteins may not account for the reductions in force production of hyperthyroid rat soleus muscle.
5.Effect of muscle contraction type and speed on tissue oxygen dynamics in the M. vastus medialis during repeated knee extension exercise.
KAZUYA YASHIRO ; TAKAKO SAKAMOTO ; TOMOHO ISHII ; KAZUHIRO SUZUKAWA ; HIROSHI KIYOTA ; MAKOTO YAMATO ; SHOICHI NAKANO
Japanese Journal of Physical Fitness and Sports Medicine 2001;50(5):625-632
The purpose of this study was to analyze the relationship between activity pattern and temporal changes in the oxygen dynamics of human femoral medial vastus muscles. Oxygen dynamics were evaluated from the surface of the body by near-infrared spectroscopy (NIRS) . Arterial occlusion tests were performed in the femoral region at a cuff pressure of 300 mmHg. Exercise type and speed were controlled by CYBEX 6000. The exercise types examined were concentric contraction (CON) and eccentric contraction (ECC) . The 3 angular velocities of 90, 120 and 180 degrees were used as the exercise speeds. Exercise was performed continuously 60 times at maximum effort. The subjects were 7 healthy males with a mean age of 19.6±0.5 years. A transient decrease in oxygen concentration was observed during circulatory occlusion ; and rapid hyperemia occurred immediately after the removal of pressure. Oxygen concentration peaked above the control level and then returned to the initial level. In the CON exercise, the initial decrease in oxygen concentration was the largest at CON 90, and a gradual increase in oxygen concentration was clearly observed during exercise. In the recovery stage, after exercise at CON 90, 120 and 180, oxygen concentration exceeded the control level before exercise, then peaked and returned to the initial level. In the ECC exercise, an initial decrease in oxygen concentration was similar to that in the CON exercise, but a gradual increase in oxygen concentration was not observed during the exercise ; nor did oxygen concentration exceed the control level in the recovery stage after the exercise.
These results indicate that an increase in oxygen level after the removal of arterial occlusion, during and after the CON exercise was much higher than the control level before the exercise, sug-gesting the involvement of reactive hyperemia and exercise hyperemia.
6.Simultaneous Cholecystectomy and Dor Operation with Encircling Endocardial Cryoablation for Ventricular Aneurysm with Malignant Ventricular Tachycardia and Acute Cholecystitis.
Takeshi Someya ; Hiroyuki Tanaka ; Satoru Hasegawa ; Keishi Ooi ; Masazumi Watanabe ; Nagahisa Oshima ; Tohru Sakamoto ; Makoto Sunamori
Japanese Journal of Cardiovascular Surgery 2000;29(5):335-338
A 68-year-old man underwent percutaneous transluminal coronary angioplasty (PTCA) to left anterior descending artery (LAD) seg 7 after acute anteroseptal myocardial infarction 8 years previously. He was admitted because of syncope attack due to sustained ventricular tachycardia and subsequent fibrillation. He was treated medically in the ICU after cardiopulmonary resuscitation. Medical treatment with amiodarone and lidocaine was not successful and he was transferred to our hospital for surgical treatment of malignant ventricular tachycardia (VT) associated with left ventricular aneurysm and acute cholecystitis that occurred during admission. Left ventriculogram showed left ventricular aneurysm (ejection fraction: 35%) without any significant coronary lesions. The patient successfully underwent a Dor operation (left ventriculoplasty), double encircling endocardial cryoablation without endocardial resection, and preoperative and intraoperative endocardial mapping. Cholecystectomy was simultaneously performed after complete closure of the median chest incision. The recurrence of VT was never recognized clinically or electrophysiologically. The extended encircling endocardial cryoablation without endocardial resection and preoperative and intraoperative electrophysiological study, was a simple and effective method for ventricular tachycardia.
7.Cardiac Surgery in Patients with Chronic Dialysis.
Susumu Manabe ; Hiroyuki Tanaka ; Koso Egi ; Satoru Hasegawa ; Masazumi Watanabe ; Nagahisa Oshima ; Toru Sakamoto ; Makoto Sunamori
Japanese Journal of Cardiovascular Surgery 2002;31(1):18-23
This study was designed to evaluate the perioperative outcome of dialysis patients undergoing cardiac surgery, who were managed with our perioperative dialysis program. Between April 1994 and August 1999, 11 patients (7 men and 4 women with a mean age of 57.3±10.3 (36-73)) with hemodialysis (HD, n=8) and peritoneal dialysis (PD, n=3) underwent cardiac surgery. The duration of dialysis was 5.6±4.3 years. Operation included mitral valve replacement (n=1) and isolated coronary artery bypass grafting (n=10). Patients with HD had single hemodialysis on the day before operation. Patients with PD were maintained on PD in the usual manner until the day before surgery. Intraoperative hemofiltration during extra-corporeal circulation and normokalemic non-depolarizing cardioplegic solution were used in all patients to avoid post-operative hyperkalemia. All HD patients had dialysis on the first post-operative day (POD 1), and then every other day. PD patients had PD soon after arriving at the ICU. Levels of serum creatinine, urea nitrogen, acid-base balance were successfully controlled within acceptable ranges. No patients required emergency HD or any post-operative managements for hyperkalemia in the ICU. Six of 8 HD patients required an increase in vasopressor because of a tendency toward hypotension and 4 of 8 patients suffered from atrial fibrillation during the initial HD on POD 1. Eight of 11 patients could be extubated on the first POD. No hospital death occurred. The use of normokalemic cardioplegic solution was useful to avoid post-operative hyperkalemia. Our perioperative dialysis programme successfully managed the perioperative clinical course of dialysed patients undergoing cardiac surgery.
8.A Case of Marfan's Syndrome with Acute Aortic Dissection during Pregnancy
Takahiro Inoue ; Yoshimasa Sakamoto ; Hiroshi Okuyama ; Makoto Hanai ; Noriyasu Kawada ; Gen Shinohara ; Kazuhiro Hashimoto
Japanese Journal of Cardiovascular Surgery 2005;34(2):116-119
We present a case of Marfan's syndrome with acute aortic dissection during the trimester of her pregnancy, who underwent a Bentall operation 2 days after emergency cesarean section. A 24-year-old woman during the 31st week of pregnancy visited our emergency room due to sudden onset of chest and back pain, though she had no abnormality until this event. Because of her tall height, spider fingers, positive wrist sign, visual disorder and scoliosis, she was given a diagnosis of Marfan's syndrome. Enhanced CT and cardiac ultrasonography revealed that she was suffering from acute aortic dissection with annulo-aortic ectasia. Since it was difficult for her to continue with her pregnancy, she underwent emergency cesarean section and gave birth to a male baby weighted 1, 706g. Although there was little likelifood of early thrombus formation in the false lumen or significant aortic regurgitation indicating an emergency operation, fear of massive bleeding from her uterus and the exfoliated surface of the placenta after cesarean section required an observation period of 2 days. We performed a Bentall operation successfully after careful sedation, ventilation and blood pressure control for 2 days.
9.Tricuspid Valve Replacement for a Patient with Corrected Congenital Transposition of the Great Vessels and Protein C Deficiency
Gen Shinohara ; Kazuhiro Hashimoto ; Yoshimasa Sakamoto ; Hiroshi Okuyama ; Makoto Hanai ; Takahiro Inoue ; Ken Nakamura
Japanese Journal of Cardiovascular Surgery 2007;36(4):193-197
Protein C (PC) deficiency is an inherited thrombotic disorder with a prevalence of 0.19% among the general population. PC deficiency is associated with an increased risk of thrombosis when other risk factors are present, such as trauma, surgery, or infection, and is an important cause of mechanical valve thrombosis. We performed tricuspid valve replacement with a 29mm Carpentier-Edwards Perimount valve in a 20-year-old man with PC deficiency. The patient had corrected transposition of the great vessels with severe tricuspid insufficiency, as well as a history of cerebral infarction. In the perioperative period, we used only heparin sodium as the anticoagulant. When we restarted administration of warfarin, changing over from heparin, transient increases of serum plasmin inhibitor-plasmin complex (PIC) and thrombin antithrombin complex (TAT) levels were observed. Despite an increased dose of heparin, an appropriate activated partial thromboplastin time (APTT) was not obtained. This suggested a hypercoagulatory state, but the postoperative course was uneventful. Management of perioperative anticoagulation, prevention of late thrombotic events, and prosthetic valve selection in this particular situation are discussed.
10.Microstructure Analysis of Immobilized Osteopenia Using Microcomputed Tomography:An In Vivo Study
Hironobu Koseki ; Makoto Osaki ; Hidehiko Horiuchi ; Yuichiro Honda ; Ryo Sasabe ; Junya Sakamoto ; Takashi Higuchi ; Sinya Sunagawa ; Minoru Okita
The Japanese Journal of Rehabilitation Medicine 2017;54(9):718-723
Objective:To assess the effects of immobilization on the three-dimensional microstructure of cortical and cancellous bone.
Methods:Eight-week-old specific-pathogen-free Wistar rats were divided into two groups:the control (n=12) and immobilized group (n=12). The hind limbs of the rats in the immobilized group were fixed using orthopedic casts for 4 weeks. The cortical bone at the mid-shaft and the cancellous bone at the distal metaphysis of the femur were analyzed using micro-computed tomography.
Results:The values of total cross-sectional area, cortical bone area, and cortical thickness in the immobilized group were significantly lower than those in the control group. Meanwhile, the relative bone volume (bone volume/total volume) and mean trabecular thickness in the immobilized group decreased and the structure model index significantly increased compared with the values in the control group (P<0.05).
Conclusion:Our rat model can evaluate the effects of load-permitting immobilization. The results of this study indicate that structural changes in immobilized osteopenia-affected bone arise mainly from thinning of the cortex and reduction of cancellous bone volume caused by a reduction of trabecular width.