Search PubMed⌕ Search

Biomedical subjects

M Morimoto

Publications and source records attributed to M Morimoto.

At least 325 records · Page 18Linked to original sources
PubMed1984

[Primary intracranial endodermal sinus tumor with a skull base extension--a case report].

The authors described a case of primary intracranial endodermal sinus tumor (EST), and presented a review of 24 reported cases. From the middle of December 1981, this 15-year-old boy experienced progressive diplopia. At the other hospital, partial removal of the intrasellar tumor was performed by a left frontotemporal craniotomy approximately 2 months after the onset of symptoms. The histological diagnosis was suspected to be a pituitary adenoma, and thereafter, 60Co irradiation was carried out for about a month. On June 5th. 1982, the patient was admitted to the Kochi Medical School Hospital, because of increasing headache with diplopia, hoarseness, dysphagia and limitation of tongue movement. On admission, he had a small stature for his age with moderate diabetes insipidus. Neurological examination showed left abducens, glossopharyngeal and vagal nerve palsies in addition to bitemporal hemianopsia. CT scans revealed a heterogenously enhanced high density mass lesion behind the dorsum sellae with an extension from the upper clivus to the sphenoid sinus. Cerebral angiograms showed posterior displacement of the basilar artery. In the endocrinological examination, panhypopituitarism was recognized with a high level of serum alfa-fetoprotein (AFP). While, serum carcinoembryonic antigen (CEA) and human chorionic gonadotropin (HCG) were in normal range. On July 1st. 1982, a left suboccipital craniectomy was performed. The tumor existed mainly in the extradural space along the clivus, and only a small intradural portion of the tumor was excited.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1984

[Alumina ceramic (Bioceram) as the cranioplastic material--experimental study and application in cranioplasty].

External decompression is an effective treatment for acute intracranial hypertension, but the repair of cranial defect by cranioplasty is necessary sooner or later. Various materials have been used for cranioplasty, such as bone, metallic materials and methyl methacrylate. Alumina ceramic (Bioceram), which is known to be extremely compatible with tissues, has already been used in the operations of not only orthopedic and oral surgery but also neurosurgery such as transsphenoidal surgery and anterior cervical fusion. At first, we implanted pieces of ceramic and small titan shield in the parietal bone of mongrel dogs. In this experimental study, tissue compatibility and osteogenesis are investigated in each case. The new bone formation was observed macroscopically and histologically around the ceramic pieces, but there were no osteogenic changes around the titan shields. Then ceramic plates, which were designed just as patients' own bone flaps, and titan shields were used for cranioplasties after decompression surgery, and compared clinically and histologically. The ceramic plate is superior than the titan shield in its strength, tissue-compatibility and excellent fit for cranial defect compared with the titan shield. There was no tissue reaction such as subgaleal fluid collection just as seen in the application of acryl resin. We believe that Alumina ceramic (Bioceram) is a good material for cranioplasty.

Aluminum↗
PubMed1984

[Contrast material with oxygenated Fluosol-DA, 20 for the protection against complications of catheter cerebral angiography].

Although computed tomography may change the criteria of cerebral angiography in neurosurgery, the neurosurgeon still requires angiographic confirmation of vascular anatomy at the operative sites, and catheterization for intra-luminal constructive surgery is also seeing progress. Cerebral angiography is a rather safe procedure; however, persistent serious neurological deficits and fatal complications are occasionally reported. The mechanisms of these complications are considered to be due to mechanically dislodged fragments of clots and/or atheroma, or direct endothelial damage by the catheter, contrast agents toxicity to brain tissue, anoxic neurocytologic injury due to the disturbance of the blood flow. Fluosol-DA (a type of perfluorochemical) has a potent oxygen-carrying capacity and has been safely used in humans as an artificial blood substitute. Meglumine diatrizoate (65% Angiografin) has not lost the x-ray opacification faculty in cerebral angiography by mixing with oxygenated Fluosol-DA, 20 up to 30 vol % of the latter in clinical use. In animal experiments, from 0.25 to 4 ml/kg of Angiografin-65 or Angiografin-65 with oxygenated Fluosol-DA, 20 were injected into the internal carotid artery of mongrel dogs. When 2.0 ml/kg of Angiografin-65 was injected into the carotid artery, remarkable arrhythmia was observed for 7.5 seconds. Blood pressure dropped 28.3 mmHg for 20.2 seconds; thereafter, it increased 25 mmHg in rebound for 15 seconds. Intracranial pressure increased 5 mmHg for 35 seconds, respiratory disturbance continued for 22.6 seconds. When a 20 vol % mixture of Fluosol-DA, 20 with Angiografin-65 was applied, these adverse reactions were markedly reduced.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

[A computed tomographic study of aneurysms of the sinus of Valsalva].

Computed tomography (CT) was performed for four patients with aneurysms of the sinus of Valsalva (each of the Konno types IVSD and IV, false aneurysm projecting into the interatrial septum, and annulo-aortic ectasia). Aneurysms were detected in three cases, and the sizes closely correlated with those of the resected specimens. However, a relatively small and mobile aneurysm of the IV type was not detected. Apparently, relatively large size (more than 10-20 mm) and immobility were necessary for the detection by CT. Reconstruction of CT images facilitated localization of the aneurysm and determining the extent of annulo-aortic ectasia. Rupture of an aneurysm was identified by observing the time course of CT values in the cardiac chambers using dynamic CT. However, better time resolution of CT is necessary for more precise diagnosis. Two-dimensional echocardiography is more convenient and diagnostically effective than CT. However, CT is a useful and non-invasive examination which overcomes the technical difficulties inherent in echocardiography, such as disturbances by the lung and other artifacts.

Adult↗
PubMed1984

Pharmacokinetics of human recombinant interferon-beta in monkeys and rabbits.

The pharmacokinetics of human recombinant interferon-beta ( ReIFN -beta) was compared with that of natural human interferon-beta (IFN-beta) in monkeys and rabbits after intravenous or intramuscular injection. After intravenous injection of 10(6) units/kg of ReIFN -beta or IFN-beta into monkeys or rabbits, serum levels of both interferons declined biexponentially. No significant differences between ReIFN -beta and IFN-beta were detected in most pharmacokinetic parameters including T1/2-beta, though T1/2-alpha of ReIFN -beta was significantly shorter than that of IFN-beta. These results seemed to be in conflict with the observed difference of stability of the interferons in vitro since ReIFN -beta was less stable than IFN-beta in monkey and rabbit serum. When ReIFN -beta (10(7) units/kg) was injected intramuscularly into monkeys or rabbits, it remained detectable in the serum for 24 hr; an absorption phase and an elimination phase were seen. However, AUC (the area under the serum concentration curve) after the intramuscular injection of ReIFN -beta was about one-half and one-third of that after the intravenous injection in monkeys and rabbits, respectively. ReIFN -beta and IFN-beta (10(6) units/kg) were both detectable in the serum after intramuscular injection into rabbits, but the level of ReIFN -beta was lower than that of IFN-beta. These results indicate that the lack of carbohydrate in ReIFN -beta did not essentially affect the in vivo pharmacokinetics in monkeys and rabbits after intravenous injection, but this was not the case after intramuscular injection.

Absorption↗
PubMed1983

Significance of renin-angiotensin system during and after surface-induced simple hypothermia in open-heart surgery.

The present studies were performed to investigate the metabolic role of the lungs in the renin-angiotensin system under hypothermia by measuring plasma renin activity, plasma angiotensin I (A I), plasma angiotensin II (A II), plasma aldosterone and plasma angiotensin converting enzyme activity on 14 patients who underwent open-heart surgery with surface-induced simple hypothermia. In addition, dog experiments were performed, in which changes of renal blood flow and angiotensin metabolism in lungs and kidneys under hypothermia were studied in vivo. The following results were obtained: 1) During and after open-heart surgery with surface-induced simple hypothermia, the homeostasis in the renin-angiotensin system is still maintained. 2) An increase of A II may play an important role in maintaining blood pressure under hypothermia. 3) Under hypothermia, the conversion of A I to A II in the kidneys may contribute to an increase of plasma A II.

Adolescent↗