Biomedical subjects

M Murase

Publications and source records attributed to M Murase.

At least 109 records · Page 6Linked to original sources

PubMed1993

Continuous retrograde cerebral perfusion for protection of the brain during aortic arch surgery.

Hypothermic circulatory arrest and selective cerebral perfusion for aortic arch surgery have been reported, but these procedures are of limited duration, require hazardous and complicated techniques and can cause clamp injury. Continuous retrograde cerebral perfusion (CRCP) is a new and simple technique for the protection of the brain during hypothermic circulatory arrest. We applied CRCP in 26 patients who underwent aortic arch surgery. Continuous retrograde cerebral perfusion was performed with a mean blood flow of 383 +/- 176, range 120-800, ml/min. The mean duration of CRCP was 63 +/- 15, range 32-92, min with the superior vena cava pressure at 15-42 mm Hg. No neurologic deficit was observed in 20 patients (90%) and only minor deficits in 2 out of the 22 cases without severe postoperative complications, allowing evaluation of the effectiveness of CRCP. Four patients had other severe complications, and the effectiveness of the method could not be evaluated. Continuous retrograde cerebral perfusion can be an excellent and safe technique which avoids clamp injury during aortic arch surgery.

Adult↗

PubMed1993

Cerebral metabolism and function during normothermic retrograde cerebral perfusion.

Retrograde cerebral perfusion through a superior vena cava (SVC) cannula is a new technique used to protect the brain during circulatory arrest. Cerebral blood flow, oxygen consumption, blood sugar consumption and auditory brain stem responses were measured at various rates (100, 200 and 300 ml min-1) of retrograde cerebral perfusion in normothermic mongrel dogs (n = 12, body-weight 13-15 kg). During perfusion about 20% of the perfusate from the SVC was returned via the aorta, while the rest drained into the inferior vena cava. External jugular venous pressure increased as the perfusion rate increased (mean(s.d.) 26.0(6.4) mmHg at a rate of perfusion of 300 ml min-1). Oxygen and blood sugar consumption also increased as the rate of perfusion increased. Retrograde cerebral perfusion at 300 ml min-1 provided half of the cerebral blood flow (mean(s.d.) 14.7(6.4) versus 34.3(7.8)ml min-1) of antegrade cardiopulmonary bypass (CPB). Analysis of the blood returned through the aorta during perfusion at a rate of 300 ml min-1 showed that mean(s.d.) oxygen consumption was about one-third (4.4(2.1) versus 12.3(7.1) ml min-1) and blood sugar consumption about 15% (17(22) versus 114(54)mg min-1) of that seen in blood returned through the SVC during CPB. Auditory brain stem responses disappeared immediately when perfusion was started but recovered completely as soon as CPB was resumed. Although the oxygen provided by perfusion was not sufficient to maintain cerebral function, it should help protect the brain during circulatory arrest.

Animals↗

PubMed1993

[Clinical study of S-1108 fine granule in the pediatric field].

S-1108 in a fine granular form was administered in 14 children and its safety and efficacy in bacterial infections were evaluated. Among them, 2 cases of cystitis and 1 case of pneumonia were considered unevaluable for the efficacy. The results obtained are summarized as follows. 1. The overall clinical efficacy rate was 81.8% in the eleven evaluable cases treated with S-1108 fine granules including 5 cases of pharyngitis, 2 cases each of tonsillitis, pertussis and cystitis. 2. Bacteriological efficacy of 100% was achieved against pathogens identified in 5 children including 1 case each of Staphylococcus aureus, Streptococcus pyogenes and Haemophilus influenzae and 2 cases of Escherichia coli. 3. The only abnormal laboratory test results observed were eosinophilia and leukocytopenia in one case each. Diarrhea was recorded in 1 case. Judging from the above results, it appears that S-1108 in the fine granular form is an effective, useful and safe antibiotic of first choice for the treatment of infections in the pediatric field.

Administration, Oral↗

PubMed1993

Nafamostat mesilate reduces blood loss during open heart surgery.

BACKGROUND: Nafamostat mesilate (FUT-175) is a protease inhibitor inactivating coagulation, fibrinolysis, and platelet aggregation. A prospective, randomized trial was performed to assess the efficacy of FUT-175 in the reduction of postoperative bleeding tendency. METHODS AND RESULTS: FUT-175 was infused at a rate of 40 mg/h during cardiopulmonary bypass (CPB) along with 300 IU/kg of heparin in 20 patients undergoing aortocoronary bypass surgery (FUT group). This group was compared with another group of 20 patients undergoing aortocoronary bypass surgery, who were given only heparin (control group). Blood concentrations of FUT-175 and activated clotting time increased after cooling, peaking at 2050 +/- 1190 ng/mL and 2136 +/- 983 seconds at the lowest temperature and recovered after rewarming to values of 166 +/- 118 ng/mL and 510 +/- 148 seconds, respectively, at the end of CPB. In the FUT group, platelet counts were significantly higher at the end of CPB than those in the control group (168 +/- 10 versus 136 +/- 9 x 10(3)/mm3, P < .05). In the FUT group, serum concentrations of beta-thromboglobulin (307 +/- 102 versus 537 +/- 391 ng/mL, P < .05), PIC (3.6 +/- 1.7 versus 5.8 +/- 3.8 micrograms/mL, P < .05) and FDP (20.2 +/- 7.0 versus 41.4 +/- 11.9 ng/mL, P < .01) were significantly lower than those in the control group at the end of CPB. However, serum concentrations of TAT, FPA, and FPB beta 15-42 showed no significant differences between groups. FUT-175 significantly reduced heparin dosage and 24-hour postoperative blood loss (19,200 +/- 3200 versus 29,100 +/- 7700 IU, P < .01, and 382 +/- 129 versus 576 +/- 375 mL, P < .05). CONCLUSIONS: FUT-175 inhibits fibrinolysis and preserves platelet counts and function during CPB and reduces blood loss during open heart surgery.

Benzamidines↗

PubMed1993

Localized argyria with chrysiasis caused by implanted acupuncture needles. Distribution and chemical forms of silver and gold in cutaneous tissue by electron microscopy and x-ray microanalysis.

A case of localized argyria with chrysiasis caused by implanted acupuncture needles in a 41-year-old Japanese woman was studied by electron microscopy and x-ray microanalysis. Large amounts of silver granules with selenium and sulfur were detected around eccrine secretory cells in much greater amounts than around ductal cells. Many granules were also observed along the outer edge of the basement membrane but never within cells or intercellular spaces. The granules were also present around blood vessels, lymphatics and nerve fibers, and in elastic fibers. Small numbers of gold fragments were also seen, mostly within macrophages. These results suggest that silver deposits extracellularly as selenide and sulfide, whereas free gold is found intracellularly.

Acupuncture Therapy↗

PubMed1993

[A case of acute hemorrhagic gangrenous acalculous cholecystitis with bile peritonitis during anti-coagulant therapy after coronary-artery bypass grafting].

Acute acalculous cholecystitis is a relatively rare complication occurring after surgery on organs other than the bile duct system. It is often misinterpreted to be a post-operative symptom, and can progress into a very serious condition with high risk of mortality if gangrene and perforation develop. Its occurrence after open heart surgery is relatively rare. We experienced a case of acute hemorrhagic, gangrenous acalculous cholecystitis that developed after coronary-artery bypass grafting. The patient, a 78-year-old man, complained post-operatively of a right upper abdominal pain. The diagnosis of acute gangrenous acalculous cholecystitis was established on the basis of abdominal sonography and CT, and emergency operation performed was successful. Etiological factors in this case may have included post-operative stasis of bile, swelling of the gallbladder, hypotension during cardiopulmonary bypass, and post-operative anti-coagulant therapy administered after open heart surgery. These factors induced intracystic hemorrhage followed by sudden exacerbation, which resulted in gangrenous cholecystitis followed by perforative biliary peritonitis.

Acute Disease↗

PubMed1993

[Cerebral renal and hepatic tissue blood flow during retrograde inferior vena caval perfusion--an experimental study in dogs].

Cerebral tissue blood flow (CBF), renal tissue blood flow (RBF), hepatic tissue blood flow (HBF), and oxygen metabolism have been measured in 8 mongrel dogs which underwent hypothermic (20 degrees C) retrograde perfusion via the inferior vena cava (IVC). IVC perfusion was performed with aortic drainage and cross-clamping of superior vena cava (SVC) at IVC pressures of 20 or 30 mmHg. CBF, RBF, and HBF at 30 mmHg of IVC pressure were 10.4 +/- 6.8, 11.4 +/- 5.5, and 19.2 +/- 11.3 mL/min/100 g. These values were 33%, 47%, and 64% of those observed with a cardiopulmonary bypass and flow rate of 1000 mL/min, and 77%, 112%, and 168% of those observed with retrograde cerebral perfusion via the both internal maxillary veins at 25 mmHg of SVC pressure. Oxygen consumption at this time was 3.78 +/- 1.77 mL/min. CBF, RBF, HBF, and oxygen consumption at 20 mmHg of IVC pressure were 7.7 +/- 4.8, 7.5 +/- 4.7, and 9.9 +/- 4.7 mL/min/100 g and 2.02 +/- 0.72 mL/min, respectively. As IVC pressure increased, CBF, RBF, HBF, and oxygen consumption increased. However, high IVC pressure by the retrograde perfusion was associated with high portal venous pressure, which would cause ascites. IVC perfusion can supply some amount of blood flow to the liver and kidney. It may therefore be advantageous to maintain proper IVC pressure to protect the abdominal organs during systemic arterial circulatory arrest under deep hypothermia.

Animals↗

PubMed1992

Retrograde cerebral perfusion through a superior vena caval cannula protects the brain.

Retrograde cerebral perfusion through a superior vena caval cannula is a new technique for protecting the brain during aortic arch operations. In mongrel dogs (n = 10; 13 to 15 kg) we have performed retrograde cerebral perfusion (300 mL/min) by infusing blood through a superior vena caval cannula with aortic and inferior vena caval drainage. We have measured the cerebral tissue blood flow, oxygen consumption, and carbon dioxide exudation during retrograde cerebral perfusion at normothermia (NT, 37 degrees C) and hypothermia (HT, 20 degrees C) and have compared these values with values obtained in dogs during cardiopulmonary bypass (1,200 mL/min). Cerebral tissue blood flow was measured by the hydrogen clearance method. During retrograde cerebral perfusion about 20% of the superior vena caval perfusate was returned through the aorta and the rest drained from the inferior vena cava. Cerebral vascular resistance during retrograde cerebral perfusion was lower than that during cardiopulmonary bypass (NT, 63.8 +/- 52.5 versus 126.9 +/- 58.4; HT, 28.4 +/- 32.8 versus 69.5 +/- 28.7 x 10(3) dynes.s.cm(-5). Retrograde cerebral perfusion provided half the cerebral tissue blood flow of cardiopulmonary bypass (NT, 14.7 +/- 6.4 versus 34.3 +/- 7.8; HT, 17.6 +/- 5.6 versus 37.2 +/- 10.6 mL/min). Retrograde cerebral perfusion also provided a third of the oxygen (NT, 4.4 +/- 2.1 versus 12.3 +/- 7.1; HT, 1.4 +/- 0.8 versus 4.2 +/- 1.3 mL/min) and discharged 20% of the carbon dioxide (NT, 0.24 +/- 0.08 versus 1.19 +/- 0.58; HT, 0.15 +/- 0.06 versus 0.51 +/- 0.17 mmol/min) when compared with cardiopulmonary bypass. Retrograde cerebral perfusion may reduce ischemic damage during interruption of cerebral blood flow.

Animals↗

PubMed1992

Cell proliferative activity of epidermal keratinocytes in hair discs.

To clarify the differences in epidermal keratinocyte proliferative activity and in postnatal developmental changes of this activity between the hair discs and the interfollicular epidermis, the incorporation of 3H-thymidine into the nuclei of the basal cells was measured by autoradiography, and the percentages of basal cells thus labelled were calculated. This percentage was higher in hair discs than in interfollicular epidermis at all stages examined. The percentage of labelled basal cells in the hair discs was 10% up to 15 days after birth, decreasing to about 6% from 20 days postnatally. These results suggest that the degree of cell proliferation in the hair disc epidermis differs from that in the surrounding epidermis and that changes in proliferative activity during the postnatal developmental stages are well correlated with the morphogenesis of the hair discs.

Animals↗

PubMed1992

Manganese-containing superoxide dismutase in blood and urine during open-heart surgery.

Concentrations of Manganese-containing superoxide dismutase (Mn-SOD) were measured perioperatively by enzyme immunoassay in serial samples of arterial and coronary sinus blood and urine taken from 18 patients undergoing mitral valve surgery. The mean Mn-SOD concentration in the arterial blood samples was 66.2 (SD 16.1 ng/ml) at induction of anesthesia, increased gradually after reperfusion and peaked on the 2nd post-operative day [150 (SD 58.3) ng/ml]. The mean concentration of Mn-SOD in the coronary sinus blood samples was significantly higher than in the arterial samples only at the 6th hour after reperfusion [97 (SD 21.8) ng/ml vs 90.3 (SD 20.9) ng/ml, p < 0.05]. Although concentrations of Mn-SOD in blood did not increase in 8 patients who underwent midline sternotomy for a mediastinal tumor, they increased dramatically in 3 patients who sustained a perioperative myocardial infarction. During open heart surgery the peak values of plasma Mn-SOD concentrations were correlated to that of plasma creatine kinase-MB concentrations (r = 0.5532, n = 18, p < 05) and cardiac ischemic period (r = 0.5186, n = 18, p < 05). Although the meaning of an increase in plasma Mn-SOD concentrations during open heart surgery is not clarified, it may be released from the heart and anywhere also in the body damaged during cardiopulmonary bypass.

Coronary Vessels↗

PubMed1991

Composition of very low density lipoproteins and in vitro effect of lipoprotein lipase.

In order to clarify the relationship between composition and lipolytic responses to lipoprotein lipase (LPL), very low density lipoproteins (VLDL) from rats or humans were incubated with a commercially available LPL or with a partially purified LPL from postheparin human plasma and fatty acids released from VLDL were determined in vitro. VLDL from rats fed a diet containing 0.25% cholesterol for 6 months were rich in cholesterol and poor in triglycerides, and released less fatty acids from incubation with LPL than those from control rats. VLDL from normo-and hypertriglyceridemic human subjects were incubated with LPL. The fatty acid release poorly correlated with the apoprotein ratios of VLDL, apo C-III/C-II, B/E, and C/E with the exception of apo B/C, but it correlated well with the ratio of triglyceride/either one of the surface components including total apoproteins, free cholesterol and phospholipids in VLDL or the ratio of the triglyceride/total sum of the surface components. The correlation coefficients between fatty acid release and a ratio of triglyceride/total surface components were 0.774 (using the commercially available LPL) and 0.786 (using the partially purified human LPL). The fatty acid release increased after pretreatment of VLDL with phospholipase A2. The phospholipid content of VLDL was reduced without significant changes in other VLDL components. Thus, the responses of VLDL to LPL treatment may depend mainly upon the surface: core relationship of VLDL rather than its apoprotein composition except in rare clinical cases such as apo C-II deficiency.

Animals↗

PubMed1991

Excitable dynein model with multiple active sites for large-amplitude oscillations and bend propagation in flagella.

The formal excitable dynein model proposed by Murase et al. (1989, J. theor. Biol. 139, 413-430) is modified to produce large-amplitude oscillations and excitability. The present model assumes that (i) each dynein arm has multiple active sites, which are distributed along most of the 24-nm distance between adjacent B-subtubule attachment sites; and (ii) any given dynein molecule tends to produce force continuously during interdoublet sliding in one direction and to produce little force during sliding in the opposite direction. Since no sliding motion occurs without superthreshold perturbations in the form of the sliding displacement, this new model also possesses an excitable nature. Once passive elastic components (e.g. nexin links and radial spokes) are incorporated into this model, oscillations with large amplitudes result. To test the ability of the model for bend propagation without a curvature-control mechanism, forced oscillations are applied to the basal end of the flagellum by the sliding displacement. It is found that bend propagation can occur even in the absence of a curvature-control mechanism.

Animals↗

PubMed1991

Mathematical modeling for the aging process: normal, abnormal and self-terminating phenomena in spatio-temporal organization.

An elucidation of the aging process is attempted using a simple one-dimensional multicellular system, a prototype of living organisms. This model analysis has the advantage of making us investigate the two types of modes of their dynamical behavior: (i) the local modes of behavior of individual cells and (ii) the global modes of behavior of the total system. At first, each cell is assumed to have biochemically excitable kinetics for local modes, and then what kind of the global modes results with change in intercellular interaction is examined. With a simple interaction as possibly occurs in the early stage of differentiation, the model displays well-coordinated spatio-temporal patterns. This may be interpreted as a normal state. With a more complex interaction as possibly occurs in the late stage of growth, however, the model produces much more erratic patterns. This may refer to an abnormal state. Interestingly, these abnormal patterns can be transformed into normal patterns, when the activity of some parts of this model is turned 'off'; the system can survive at the sacrifice of its parts. This makes us imagine that programmed cell death plays an important role in development during morphogenesis. When individual cells become less sensitive to intercellular signals and still possess intrinsic excitability, then the normal patterns are developed for a short while before being replaced by rather irregular patterns. As time proceeds, however, all activity of them disappears. We call this a 'self-terminating' phenomenon, which may refer to aging. This strongly suggests that the loss of the total system function, leading to death, results from a global mode of system failure but not from a local mode of subsystem failure.

Aging↗

PubMed1991

Comparative study between magnetic resonance imaging and histopathologic findings in ossification or calcification of ligaments.

Magnetic resonance imaging findings were compared with histopathologic specimens of ossified or calcified ligaments, including the surrounding tissue, to evaluate the usefulness of magnetic resonance imaging as a means to predict the progression of ossification. In addition, factors influencing signal intensity were evaluated by histochemical and immunohistochemical analyses. The area of low signal intensity corresponded to the hyperplastic ligament around the ossification, and to the transitional area between the ligament and the ossification. A mineralization front and chondrocyte proliferation with strong metachromasia were recognized in these areas. The presence of a low-intensity signal area suggested the progression of ossification. The isointensity signal corresponded to proliferation of small vessels in the hyperplastic ligament, presumably representing the initiation of ossification. Histochemically, the metachromasia was intense at the transitional area between the ligament and the ossification, and the main constituent in these areas was chondroitin sulfate. Immunohistochemically, S-100 protein, transforming growth factor-beta 1, and Type II collagen showed an intense immunoreactivity in the chondrocytes, indicating increased production of the extracellular matrix. We postulate that the activation of chondrocytes and the alteration of the extracellular matrix may have affected the signal intensity.

Aged↗

PubMed1991

[T-serotype distribution of group A hemolytic streptococci in a rapidly expanding residential area in Sanda City, Hyogo Prefecture, with reference to an outbreak of serotype T-28 in autumn, 1988].

In the fall of 1988, an outbreak of streptococcal infections was observed at 2 pediatric clinics in Sanda City, Hyogo prefecture. The 2 clinics were independent of each other; one (clinic A) was located in the down town area, in the older part of the city, where there is little population turn over, while the other (clinic B) was in a newly developed-fast growing residential district. The strains and the distribution of T-serotypes isolated at each location are as follows: clinic A; 58 strains (34.5% serotype T-4, 31.0% serotype T-12, 10.3% serotype T-1, and 23.3% serotype T-28), clinic B; 43 strains (48.8% serotype T-28, 23.3% serotype T-12, 11.6% serotype T-4 and 7.0% serotype T-1). According to the data from Kobe City infectious disease surveillance center, there were a total of 102 group A hemolytic streptococci strains isolated in 1988, the T-serotypes distribution of which was as follows: 47.0% serotype T-4, 15.7% serotype the T-12, 10.8% serotype T-1 and 9.8% serotype T-28. Serotype T-4 was dominant here, as it was in location A of Sanda City. The epidemic proportion of serotype T-28 found at location B is considered to be due to the fact that location B has very little social interaction with location A and other areas. No difference was observed among the different serotypes on the drug susceptibility test: all strains showed a sensitivity to ampicillin and penicillin G, but were resistant to tetracycline and chloramphenicol.

Adolescent↗

PubMed1991

[Evaluation of maintenance of cardiac output during DDD and VVI pacing by exercise Doppler echocardiography].

To evaluate the efficacy of DDD pacing for cardiac reserve, we assessed increases in the stroke volume and cardiac output during randomized treadmill exercise in 16 patients by DDD and fixed-rate ventricular (VVI) pacing. The stroke volume index and cardiac index were determined using suprasternal Doppler measurements. Ten patients who showed sinus rhythm during exercise were excluded from this study. Compared with the findings during VVI pacing, those during DDD pacing showed: 1) a greater exercise-induced positive chronotropic response (mean maximum heart rate 122 +/- 22 beats/min vs 70 beats/min, p < 0.01), 2) a lesser increase in the stroke volume index (34 +/- 7 to 39 +/- 9 ml/m2 vs 31 +/- 7 to 49 +/- 11 ml/m2, p < 0.05), 3) a greater increase in the cardiac index (2.43 +/- 0.45 to 4.48 +/- 1.36 L/min/m2 vs 2.22 +/- 0.47 to 3.43 +/- 0.45 L/min/m2, p < 0.05), and 4) prolongation of exercise duration (6.35 +/- 2.00 min vs 5.97 +/- 1.81 min, NS). These findings indicated that VVI pacing promoted a greater stroke volume than DDD pacing, which provides a compensatory increase in contractility and the preload in cases without an increase in heart rate during exercise, however, the increase in cardiac output was insufficient due to the absence of a chronotropic response. In conclusion, a DDD pacemaker could effectively increase heart rate, causing a significant increase in cardiac output and extending exercise duration.

Adult↗

PubMed1991

[Pharmacokinetical and clinical study of cefpirome in children].

This study describes the pharmacokinetic characteristics and clinical usefulness of cefpirome (CPR) in children. Mean half-lives of 20 mg/kg and 40 mg/kg of CPR injected intravenously in one shot were 1.18 and 1.34 hours, respectively, and their mean recovery rates into urine were 69.8 and 72.2%, respectively. Minimum inhibitory concentrations of CPR against Staphylococcus aureus, Streptococcus pneumoniae, Klebsiella pneumoniae, Escherichia coli and Haemophilus influenzae were the same as or lower than those of ceftazidime. CPR was clinically effective in 14/15 of patients with bacterial infections; 8/9 of pneumonia, 2/2 of bronchitis, 1/1 of pharyngitis, 1/1 of tonsillitis, 1/1 of osteomyelitis, 1/1 of urinary tract infection. No clinically overt side effects of CPR were found, while an increase of eosinophils in blood was observed in 2 cases, and an increase of platelet in blood in 1 case and an elevation of serum GPT activity in 1 case were also observed. These findings indicate that CPR is useful for the treatment of bacterial infections in children.

Adolescent↗

PubMed1991

[An operative case of vascular ring (Edwards III B type)].

A 28-year-old female with dysphagia due to the vascular ring (Edwards III B type) was operated successfully. Preoperative chest x-ray film showed a defect of the left first arch and deviation of the lower trachea to the left side. Esophagogram disclosed the upper thoracic esophagus stenotic and deviated left anteriorly. Arch aortogram showed the right aortic arch and aberrant left subclavian artery with the aortic diverticulum. Operation was performed through a left thoracotomy. Esophagus was squeezed by the aortic arch, aortic diverticulum and left ligamentum arteriosum. The left ligamentum arteriosum was divided. Its stump of aortic side was sutured and fixed with paravertebral pleura so that the squeeze by the diverticulum was released. The stenotic esophagus was dissected from surrounding tissue and its satisfactory distensibility was confirmed. Dysphagia disappeared after operation and postoperative esophagogram showed marked improvement of the stenosis. Eleven operated cases of this type of vascular ring in adult have been reported in Japan. Remarkable improvement of dysphagia was observed in all cases. Thus surgical treatment is recommended for cases suffering from severe dysphagia.

Adult↗