Biomedical subjects

F Mori

Publications and source records attributed to F Mori.

At least 127 records · Page 7Linked to original sources

PubMed1991

Pathological studies on central nervous tissues of rats infected with Rattus serotype hantavirus (SR-11 strain).

Newborn rats inoculated intraperitoneally with a hantavirus strain (SR-11) developed neurological signs such as ataxia and limb paralysis. The main histological lesions were scattered and multiple neuronal degeneration and necrosis with eosinophilic cytoplasmic inclusion bodies (CIB) in the brain, spinal cord and ganglia. Immunohistochemically, the viral antigen was detected in neurons, capillary endothelial and glial cells throughout the nervous tissue and CIB were identified as consisting of hantaviral antigen (nucleocapsid protein). Ultrastructurally, CIB in the neurons consisted of an accumulation of granular or filamentous materials, or both. They were seen near a well-developed Golgi apparatus and associated with well-developed rough endoplasmic reticulum and increased numbers of ribosomes. The present results suggested that this virus strain was highly infective in neurons of the newborn rats and that excess production of viral antigen which accumulated as CIB resulted in the neuronal changes.

Animals↗

PubMed1991

Protection of acetylcholinesterase by meptazinol in mice exposed to di-isopropyl fluorophosphate. Comparison with physostigmine.

The protective action of meptazinol against acute di-isopropyl fluorophosphate (DFP) intoxication has been evaluated in mice by measuring the effects on the DFP LD50 of the pretreatment of the animals with increasing doses of the drug. Meptazinol at the doses 15, 30 and 45 mg kg-1 injected 15 min before DFP caused a dose-dependent increase in the DFP LD50, resulting in protection ratios equal to 2.1, 4.8 and 9.7, respectively, in the absence of atropine and 2.5, 4.7, and 8, respectively, in the presence of atropine sulphate (17.4 mg kg-1) therapy. Under the same experimental conditions, the protective ratio of 0.1 mg kg-1 physostigmine sulphate was 2.2 and 7.3 in the absence and presence of atropine therapy, respectively. In separate experiments, the time course of acetylcholinesterase (AChE) activity recovery was evaluated in the brain and diaphragm of mice pretreated with meptazinol (30 mg kg-1) or physostigmine (0.1 mg kg-1) 15 min before poisoning with DFP (8 mg kg-1). Ten minutes after poisoning, residual AChE activity in the brain averaged 4, 47 and 15% of that in controls in animals pretreated with atropine alone, atropine plus meptazinol or atropine plus physostigmine, respectively. Twenty four hours after poisoning, brain AChE activity averaged 31 and 47% of that in controls in mice protected by meptazinol and physostigmine, respectively. The data from the diaphragm closely paralleled those from the brain. It is concluded that high doses of meptazinol exert antidotal action against acute DFP poisoning in the mouse comparable in efficacy with that of physostigmine combined with atropine.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholinesterase↗

PubMed1991

[Chylothorax developed after cardiac surgery in children: a report of three cases].

Two children developed chylothorax after median sternotomy and a third child developed chylothorax after a Blalock-Taussig operation under the left thoracotomy. The first patient had a closure of ASD and a pulmonary valvotomy and then later developed chylothorax. The thoracic duct was ligated 10 cm just above the diaphragm at 28 days after the first operation because of unsuccessful conservative treatment. The second patient had a Blalock-Taussig operation and the third patient had radical operation for ECD and both developed chylothorax. The latter two patients were cured with conservative treatments such as the administration of Medium Chain Triglyceride or total parenteral nutrition with thoracic drainage. Children who developed chylothorax after cardiac surgery should be treated conservatively for at least the early postoperative period when circulatory and/or respiratory conditions are still unstable.

Child, Preschool↗

PubMed1991

[Centrifugal pump as right ventricular assist pump in the treatment of right ventricular failure following resection of left atrial myxoma].

A 31-year-old woman had a left atrial myxoma associated with severe pulmonary hypertension and respiratory failure because of incarceration of the tumor to the mitral valve. Emergency surgery was performed, but the patient could not be weaned from cardiopulmonary bypass because of right ventricular failure. A Biomedicus centrifugal pump was used as a right ventricular assist pump. The result was a successful termination of cardiopulmonary bypass. With the support of an intra-aortic balloon pump, the right ventricular assist pump was removed 38 hours after the operation, and the intra-aortic balloon pump was terminated 2 days later. The centrifugal pump is very useful at the majority of centers where the pneumatically activated bi-valved ventricular assist device is unavailable. The Biomedicus centrifugal pump can be easily applied for treatment of perioperative right ventricular failure and is very useful for short-term use without systemic anticoagulants.

Adult↗

PubMed1990

Chemical composition, particle size range, and biological activity of some low molecular weight heparin derivatives.

Several low molecular weight (LMW) heparin sodium derivatives from different sources, as well as some related regular heparin sodium preparations, were examined for chemical composition by high field (300 MHz) 1H NMR spectroscopy, for particle size range by quasi-elastic light scattering (QELS) methods, and for anti-coagulation potency and anti-factor Xa activity by the standard U.S. Pharmacopeial assays described for regular heparin. The NMR spectra provided insight into possible modes of depolymerization used to generate the LMW heparins, as well as into the presence of dermatan sulfate or other chemical contaminants. The QELS analysis permitted the heparin preparations to be characterized and compared by virtue of their distinctive particle size distributions.

Dermatan Sulfate↗

PubMed1990

The effect of the left ventricular assist device on the myocardium during reperfusion after coronary artery occlusion.

The effect of the left ventricular assist device (LVAD) during reperfusion after acute coronary occlusion was evaluated in a canine experimental model. The left circumflex artery was occluded for one hour, then reperfused for six hours immediately after removal of the occluder. Sixteen mongrel dogs were divided into the following two groups; a control group comprised of 7 dogs not given the LVAD support and another group comprised of 9 dogs (the LVAD group) assisted by LVAD for five hours during reperfusion. Throughout the study period, there was no significant difference in heart rate, aortic pressure or PA pressure between the two groups. However, LA pressure was significantly lower, while cardiac output, LV dp/dt, and LVSW were significantly higher in the LVAD group compared to the control group. Regional myocardial blood flow in the LCx area was significantly decreased after LCx occlusion in both groups but in the LVAD group, it recovered to the same level as before LCx occlusion after the beginning of reperfusion, while in the control group it remained significantly low throughout reperfusion. The LVAD group showed a positive myocardial lactate extraction in the early reperfusion period however, there was persistent lactate production in the control group. Thus, the unloading effect of LVAD during reperfusion after acute coronary artery occlusion improved regional myocardial blood flow and myocardial lactate metabolism and consequently, left ventricular function showed better recovery even after weaning from the LVAD support.

Animals↗

PubMed1990

Effect of combined dopamine and bunazosin on the ischemic heart after occlusion of the coronary artery.

In order to investigate whether dopamine combined with bunazosin improves cardiac function, the global and regional cardiac function and regional blood flow of 7 anesthetized dogs were analyzed before and after occlusion of the left anterior descending coronary artery (LAD), then after 10 micrograms/kg/min dopamine infusion following the LAD occlusion, and again after a bolus infusion of bunazosin 250 micrograms/kg. Dopamine with bunazosin reduced left atrial pressure from 4.9 +/- 0.9 to 3.1 +/- 0.5 mmHg (p less than 0.05) and improved cardiac output from 1.22 +/- 0.15 to 1.50 +/- 0.14 L/min (p less than 0.05), maximum positive left ventricular dp/dt from 1721 +/- 202 to 3600 +/- 663 mmHg/sec (p less than 0.05) and the time constant from 45.2 +/- 5.0 to 27.5 +/- 4.6 msec (p less than 0.01). Bunazosin added to the dopamine reduced the elevated left ventricular peak systolic pressure caused by dopamine from 130 +/- 7 to 113 +/- 8 mmHg (p less than 0.01). With regard to the regional wall motion, the impaired LAD-delta L (the segment systolic shortening) and LAD-Elmax (the slope of peak systolic pressure--endsystolic length relation) following the LAD occlusion improved from 0.5 +/- 2.5 per cent to 5.9 +/- 2.6 per cent (p less than 0.01) and from 50 +/- 9 to 82 +/- 14 mmHg/mm (p less than 0.01) after the infusion of dopamine with bunazosin. Dopamine greatly increased the Rate Pressure Product (RPP) from 12610 +/- 1120 after LAD occlusion to 16950 +/- 1420, whereas dopamine in combination with bunazosin did not increase the RPP due to a drop of LV-PSP with little change in regional myocardial blood flow. It was concluded that combining dopamine with bunazosin was useful for improving both the global and regional cardiac functions of the ischemic heart.

Adrenergic alpha-Antagonists↗

PubMed1990

Clinical trial of nicardipine cardioplegia in pediatric cardiac surgery.

To clarify the effectiveness of nicardipine, one of the dihydropyridine calcium-channel blockers, for myocardial protection during cold potassium cardioplegic arrest in pediatric cardiac surgery, a clinical trial of nicardipine (0.25 mg/L) added to potassium cardioplegic solution was performed in children undergoing surgical repair of congenital heart diseases. Twenty patients were selected to receive nicardipine cardioplegia and 13 patients received a standard potassium cardioplegia, serving as a control group. Nicardipine cardioplegia provided better cardiac performance in the early postoperative period and reduced release of the MB isozyme of creatine kinase, as determined during a 48-hour postoperative period. These results suggest that nicardipine added to cold potassium cardioplegic solution offers additional protection for the myocardium during ischemia and postischemic reperfusion in pediatric cardiac surgery.

Blood Pressure↗

PubMed1990

Glycine-related amino acids stereoselectively affect N-methyl-D-aspartate receptor-mediated contractions of guinea pig ileum: comparison with the inhibition of strychnine-insensitive [3H]glycine binding to rat cortical membranes.

Ten microM glycine, D-serine and D-alanine potentiated L-glutamate (30 microM)-induced contractions of the guinea pig ileum by an average of 35, 53 and 24%, respectively. On the contrary, D-cysteine, at the same concentration, caused a 21% inhibition of the contractile response to L-glutamate. This inhibitory effect of D-cysteine was abolished by 10 microM glycine. The corresponding L-isomers of these amino acids, namely L-serine, L-alanine and L-cysteine and the other amino acids tested, possessed negligible activity or were inactive in this test. The IC50 values of the same compounds for strychnine-insensitive binding of [3H]glycine (20 nM) to cortical membranes from the brain of the rat were: 0.26 microM, glycine; 1.2 microM, D-serine; 2.1 microM, D-alanine; 8.6 microM, D-cysteine; 51 microM, L-serine; 90 microM, L-alanine; greater than 1000 microM, L-cysteine. On the whole, these results point out a strict requirement for stereoselectivity for both of the effects examined. In addition, the results obtained in the ileum preparation suggest that D-cysteine may act as an antagonist, rather than as an agonist at the glycine site which regulates the responses of N-methyl-D-aspartate receptors.

Amino Acids↗

PubMed1990

[Evaluation with Doppler echocardiography of the Bjork-Shiley Monostrut prosthesis in the mitral position].

The Doppler characteristics of Björk-Shiley Monostrut prostheses in mitral position were studied in 53 patients (35 women; 18 men; mean age 53.8 yrs). Valvular function was considered normal on the basis of clinical and echocardiographic evaluation. Mean follow-up after surgery was 23.9 +/- 12.0 months (range 9-53). M-mode, two-dimensional and colour flow mapping echo were performed in each patient. Transvalvular blood flow characteristics were examined by colour flow imaging whereas peak and mean gradient through the valve, pressure half-time and prosthetic area were calculated using continuous wave Doppler. In 84% of patients, colour flow mapping showed a transprosthetic flow with 2 jets; in 78% the jets were different: the main one was directed towards the free wall of left ventricle in 52% and towards the interventricular septum in 48%. Thus, the main jet direction was dependent on the spatial position of the prostheses and the orientation of the disc. In 16% a single jet flow was present during the whole diastole. CW Doppler showed the following parameters: peak velocity 1.6 +/- 0.3 m/s; peak gradient 10.7 +/- 3.9 mmHg; mean gradient 3.8 +/- 2.3 mmHg; pressure half-time 83.3 +/- 16.6 msec; prosthetic area 2.7 +/- 0.51 cm2. No statistically significant difference was found between different size prostheses. Our data show the excellent long term hemodynamic parameters of Björk-Shiley Monostrut mitral prosthesis and confirm the value of colour flow mapping in identifying normal transprosthetic flow profile.

Adult↗

PubMed1990

[Effects of hypertrophy on cardiac systolic and diastolic performance in athletes with mild hypertension].

Aims of the study has been the evaluation of morphological and functional aspects of left ventricle in subjects undergoing mild hypertension and sport adaptation effects. These evaluations have been carried out by Echo-Doppler both at rest and during sharp increase in after load induced by isometric stress. Together with the morphological parameters represented by mass index and by radius to thickness ratio, we have studied stroke volume and transmitral flow pattern assessing the maximum flow velocity during rapid filling phase (E), during atrial contraction phase (A) and their ratio (E/A). We have studied 31 male subjects from 39 to 60 (average 47) exercising twice or three times a week (in the main, aerobic sports such as road cycling). They were subdivided into two groups, the first included 16 subjects with mild hypertension (AP = 155 +/- 9/97 +/- 5 mmHg) the second included 15 normotensive subjects without known pathologies, comparable for age and body surface (AP = 125 +/- 15/77 +/- 10 mmHg). Hypertensive subjects exercising regularly, showed a mass index (164 +/- 42 g/m2) significantly higher than the controls (139 +/- 35 g/m2, P less than 0.01) but they ke a normal filling pattern at rest and similar stroke volume values. During isometric exercise instead, the velocities of E and A waves showed a different trend in the two groups with a higher reduction in E/A ratio in hypertensive subjects. The per cent decrease in this ratio turned out to be 15% in the control group and 33% in hypertensive subjects (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

[The effect of the co-existence of verapamil and residual propranolol on the left ventricular contractility].

The combined effect of the residual propranolol, which was administrated up to the coronary revasculization, and verapamil, anti-supraventricular tachycardia drug, on the left ventricular contractility was evaluated with left ventricular end-systolic pressure-diameter relationship. Methods; Eighteen sheep were instrumented with ultrasonic crystals on the anterior and posterior wall, endocardium and epicardium. A pressure transducer was placed in the left ventricle. Propranolol (0.15 mg/kg) (n = 6) or verapamil (0.15 mg/kg) (n = 6) or both drugs (n = 6) were administrated intravenously, and cardiac function was evaluated. Results; In combined group, end-systolic pressure-diameter ratio (Emax) was significantly decreased (2.95 +/- 0.24 mmHg/mm) as compared to the control group (7.95 +/- 0.83), propranolol group (6.27 +/- 0.78), and verapamil group (4.54 +/- 0.77). Conclusion; Co-existence of propranolol and verapamil significantly decreased cardiac contractility. Therefore verapamil should be administrated carefully in the presence of residual propranolol, and the co-existence of both drugs must be limited.

Animals↗

PubMed1990

[A successful removal of a left atrial massive ball thrombus caused by mitral stenosis].

A 66-year-old female with a mitral stenosis and a left atrial massive ball thrombus is presented. She was admitted due to a transient right hemiplegia and a speech disturbance. This thrombus had been detected preoperatively by an echocardiogram and a left atriography. A mitral valve replacement using a Björk-Shiley valve 27 mm, accompanied with the removal of the thrombus was performed. The ball thrombus was dark red, 55 x 35 x 32 mm in size and 15 g in weight. After the surgery, the patient progressed well. Because of the high frequency of peripheral embolism and of sudden death, a left atrial ball thrombus should be removed immediately.

Female↗

PubMed1990

[Mitral valve prolapse. A prevalence study using bidimensional echocardiography in a young population].

The results of many studies on the prevalence of mitral valve prolapse have been greatly influenced by the diagnostic methods and criteria adopted as well as by population selection. The method of choice today is 2d-echocardiography because of its ability to highlight both movement anomaly (i.e. functional prolapse) and any eventual morphological variations of the mitral valve (i.e. anatomic prolapse). The latter (chordae lengthening, thickening and overabundance of the leaflets, dilation of the valvular ring) are, nowadays, considered especially important even as predictive factors of complications. Therefore we studied the prevalence of these two types of prolapse in a population of 420 university students. Functional mitral valve prolapse was found in 27/420 (6.4%) and anatomical prolapse in 2 cases (0.5%). No auscultatory finding was present in 24/27 patients with functional prolapse. There was no correlation between the two types of mitral valve prolapse and the body mass index, the fractional shortening of the left ventricle and symptoms (dyspnea, palpitations, precordial pain, dizziness). We think that the distinction between the two types of mitral valve prolapse should prove very useful for the comparison of results in future epidemiological studies. Follow-up of both groups of patients will hopefully clarify the usefulness of such distinction from the clinical point of view.

Adult↗

PubMed1990

[A surgical case of Hodgkin's lymphoma originated from thymus].

We experienced a surgical case of large Hodgkin's lymphoma of the thymus. An 18 year-old male who had been complaining of a persistent cough was admitted to our hospital. Chest X-ray film showed an anterosuperior mediastinal tumor. But there was no superficial lymphadenopathy and hepatosplenomegaly. He received a surgical extirpation of the tumor approached by median sternotomy. The tumor expanded to the whole antero superior mediastinal region, which was 18.5 X 15 X 5.5 cm in size, surrounding the trachea and main branch of aortic arch and veins. The tumor directly invaded the bilateral pleura and left innominate vein, so these regions were resected with the tumor. The left innominate vein was reconstructed with a PTFE graft. The pathological diagnosis was Hodgkin's lymphoma nodular sclerosis type by LSG classification. A post operative course was uneventful.

Adolescent↗

PubMed1990

[Noonan syndrome associated with atrial septal defect, ventricular septal defect and pulmonary stenosis--a case report].

A 10 year old girl with diagnosis of Noonan syndrome was admitted to our hospital because of easy fatiguability and cardiac murmur. She had a peculiar face with hypertelorism, saddle nose, webbed neck and kyphosis. Chromosomal analysis demonstrated normal 46 XX pattern. Associated cardiac anomalies in this case were atrial septal defect, ventricular septal defect and pulmonary stenosis caused by pulmonary valvular dysplasia. The cardiac anomalies were corrected successfully and postoperative clinical course was uneventful.

Child↗

PubMed1990

[Significance of measuring Cu, Zn-superoxide dismutase (SOD) levels in open heart surgery].

Cu, Zn-SOD levels, free hemoglobin (Hb) and CPK-MB were measured in 18 patients undergoing open heart surgery. In order to evaluate the serum level of Cu, Zn-SOD, the ratio of Cu, Zn-SOD/free Hb was used to eliminate an influx of Cu, Zn-SOD released from erythrocytes during cardiopulmonary bypass. The value of Cu, Zn-SOD/free Hb was decreased significantly 30 minutes after aortic declamping and the minimal value was indicated 1 hour after the termination of cardiopulmonary bypass compared with the preoperative status. We thought that the decrease was due to the consumption of SOD competing against free radical generation. The correlation between the minimal value of Cu, Zn-SOD/free Hb and the ischemic time was apparent but the correlation between the minimal value of Cu, Zn-SOD/free Hb and the value of peak CPK-MB was not determined. It was suggested that the serum free radicals were not only derived from the heart but also from the lung or other parts of the body during open heart surgery.

Adult↗

PubMed1990

Improved radioassay of anti-acetylcholine receptor antibody: application for the detection of extremely low antibody titers in sera from patients with myasthenia gravis.

We examined sera from 113 patients with myasthenia gravis (MG). Most of the patients with ocular MG without thymoma and 15% of the patients with generalized MG had immunoprecipitation (IP) titers of anti-acetylcholine receptor (anti-AChR) antibodies within the normal range for healthy subjects. We developed a highly sensitive radioassay using Staphylococcus aureus cells, and re-examined the 86 serum samples that had negative titers by IP. Using the radioassay, we detected anti-AChR antibodies in 27 (31%) of these myasthenic sera, of which 19 were from ocular MG patients without thymoma. By combining the standard IP assay and our new radioassay, we increased to 50% the overall percent positivity of detecting nonblocking-type antibodies in ocular MG patients without thymoma. We detected no anti-AChR antibodies in nearly all patients with various immunological and neurological diseases other than MG, and in all the healthy controls. The data for these sera indicate that in some cases the standard IP assay gives false-negative reactions. Thus, use of the more sensitive radioassay is preferable for accuracy.

Acetylcholine↗