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Biomedical subjects

S Oi

Publications and source records attributed to S Oi.

At least 127 records · Page 7Linked to original sources
PubMed1981

Hydrocephalus associated with intraspinal neoplasms in childhood.

We report nine cases of obstructive or communicating hydrocephalus among 64 infants and children with intraspinal neoplasms. There were three intramedullary, four intradural, and two extradural tumors. Although four patients had papilledema, and five myelograms revealed total block, the total CSF protein level was not always elevated in the fluid above the intraspinal lesion. Analysis of these nine cases permits several different pathogenetic considerations of hydrocephalus associated with intraspinal tumors. The high incidence (14%) of this coexistent syndrome might be a characteristic of intraspinal neoplasms in infants and young children.

Child↗
PubMed1981

Structures of heterooligosaccharides synthesized by levansucrase.

In the presence of excess amounts of various monosaccharides as acceptors, Bacillus subtilis levansucrase synthesized various heterooligosaccharides as a result of transfer of the fructosyl residue from sucrose. The saccharides produced in the presence of D-glucose, D-mannose, and D-xylose were all non-reducing disaccharides and were identified as beta-D-fructofuranosyl-alpha-D-glucopyranoside (sucrose), beta-D-fructo-furanosyl-alpha-D-mannopyranoside (mannosucrose), and beta-D-fructofuranosyl-alpha-D-xylopyranoside (xylsucrose), respectively. The saccharides produced in the presence of D-galactose were also non-reducing, but consisted of di-, tri-, and tetrasaccharides. The di- and trisaccharides were galsucrose and 6F-beta-D-fructofuranosyl-galsucrose. The saccharide synthesized in the presence of L-arabinose was a reducing saccharide and was determined to be 4-O-beta-D-fructofuranosyl-L-arabinose. In the presence of D-fructose, several reducing levan oligomers, levanbiose, levantriose, levantetraose, etc., were produced, which were not observed in the synthesis of levan from sucrose alone.

Arabinose↗
PubMed1980

The molecular structure of low and high molecular weight levans synthesized by levansucrase.

The levan synthesized by Bacillus subtilis levansucrase in the presence of alcohols was of only high molecular weight, while in solutions of high ionic strength only low molecular weight (MW) levan was produced. The addition of low MW levan to the enzyme reaction mixture at low ionic strength stimulated synthesis of a high MW levan, but the levan added was not incorporated into this high MW levan. Methylation analysis revealed that low MW levans contained glucose, which was isolated as 2,3,46-tetra-O-methyl alditol acetate showing that the glucose units existed as terminal residues. The molecular weight of levan estimated on the basis of glucose content coincided with that determined by the gel filtration method. Methylation analysis also revealed that the number of fructose residues of the linear fraction linked by leads to 6(F)2 leads to type bonds was 22 for levan with a molecular weight of (8.4(-22)) x 10(3), while it was 11 for that of 2,000 x 10(3). The number of (formula: see text) type branched residues increased with increase in the molecular weight of the levan synthesized.

Bacillus subtilis↗
PubMed1980

[Brain tumors in infants and children--factors affecting prognosis. (Part 1) Ependymoma (author's transl)].

Ependymomas constitute 6.1 to 12.7 percent of pediatric intracranial neoplasms with a predominance of male patients, younger children and infratentorial involvement. Although there is a generally accepted pathological classification of ependymoma, the prognosis and surgical results of this tumor do not always correlate with the apparent tumor malignancy. We analyzed 38 ependymomas in children in light of the prognosis and its affecting factors. Thirty-three were intracranial and 5 were intraspinal. Among 33 intracranial ependymomas, 20 were infratentorial (4th ventricle) 9 were in the lateral ventricle or cerebral parenchyma and 4 were in the para third ventricular region. In age distribution, 3rd or 4th ventricular ependymomas were seen in younger children, under the age of 10 years, except for one child; while ependymomas in the lateral ventricle, cerebral parenchyma or spinal cord were more common in older children. Malignant ependymomas or ependymoblastomas were found in 14 intracranial ependymomas involving equally each location. The surgical mortality in 38 ependymomas was 0. The five year survival rates in malignat ependymomas and low grade ependymomas were not significantly different. However, the five year survivals in the 3rd or 4th ventricular ependymomas were extremely poor, 20% and 0% respectively, while lateral ventricular or intraparenchymal ependymomas had an excellent survival rate of 60% at five years. The patients with total tumor removal survived significantly longer (5 year survival 50%) than with subtotal resection (5 year survival 25.5%) or biopsy (5 year survival 16.6%). All patients except 4 were treated with radiation therapy. The clinical significance of radiation therapy will also be further discussed.

Cerebral Ventricle Neoplasms↗
PubMed1979

Synthesis of levan by levansucrase. Some factors affecting the rate of synthesis and degree of polymerization of levan.

The addition of levan as a so-called "acceptor" accelerated the rate of polymerization of levan catalyzed by levansucrase [EC 2.4.1.10]. However, this effect was seen only under conditions of low ionic strength. Under conditions of high ionic strength, only levan with an average degree of polymerization (DP) of 120 was synthesized with a reasonable yield. Incorporation of [14C]fructose residues into levan of high molecular weight (DP 1,200) added as an "acceptor" at high ionic strength was slight. It is suggested that the DP of levan synthesized is generally regulated by ionic strength, and that enzymic synthesis of levan occurs in the absence of an "acceptor."

Bacillus subtilis↗
PubMed1979

Neurogenic tumors of the brachial plexus: report of two cases.

Two cases of solitary neurogenic tumors of the brachial plexus unassociated with von Recklinghausen's disease are presented. One patient had a malignant schwannoma. The lesion of the other patient was benign and was diagnosed pathologically as a plexiform neurofibroma. These uncommon neurogenic tumors of the brachial plexus unassociated with von Recklinghausen's disease pose diagnostic and surgical problems. The initial clinical presentation is usually that of a painless supraclavicular mass. At the time of surgical exploration, the exact site or nerve of origin cannot always be identified. If motor loss is caused by such a tumor of the brachial plexus, it usually indicates a malignant lesion and a poor prognosis. Although wide radical excision of a malignant neurogenic tumor is indicated surgically, one of our patients had an early malignant recurrence that necessitated immediate amputation.

Adult↗
PubMed1979

Xanthogranuloma of the third ventricle. Case report.

The case history of a patient with a xanthogranuloma of the third ventricle is presented. This type of lesion formed by desquamation of epithelium is usually noted as an incidental autopsy finding in the choroid plexus of the lateral ventricles. Total removal via a transcortical transventricular route led to complete recovery. These tumors should be suspected in the geriatric population. The computerized tomography findings and a review of the literature are included.

Age Factors↗
PubMed1978

[Metastatic breast carcinoma in the pituitary gland (author's transl)].

Metastatic carcinoma was found in 9 pituitary glands (24%) of 37 patients undergoing transphenoidal hypophysectomy for diffuselly metastatic breast carcinoma. In all cases the preoperative neurological examination was negative, as were neuroradiological studies, including skull X-ray, tomograms of the sells turcicabrain scan, and angiography. Diabetes insipidus, however, was seen more frequently in patients with pituitary metastasis preoperatively (3 of 9) and postoperatively (8 of 9). Four of the nine patients with pituitary metastasis developed severe diabetes insipidus, which continued more than one month, while similar severe disease was seen in three of twenty-seven cases with no pathological evidence of pituitary metastasis. The prognosis in patients with pituitary metastasis was poor, with seven of the nine dying with an average survival of eighteen months. Pathological studies disclosed metastatic lesions in the anterior lobe (78%), posterior lobe (44%), and stalk (11%). The study emphasized that pituitary metastases, usually considered to be rare, occurred in 24% of patients with diffusely metastatic breast carcinoma. Such metastases correlate with the development of severe diabetes insipidus and with poor prognosis.

Adult↗
PubMed1977

[Computerized axial tomography in the diagnosis of multiple brain tumors-correlation with angiography and nuclear scanning (author's transl)].

Results of Computerized Axial Tomography with and without intravenous contrast (60% Conray) in 24 patients with multiple brain tumors were analyzed. Of the 24 patients, 19 had metastatic brain tumors, 4 multiple gliomas and 1 patient had multiple meningiomas. Data obtained by C.T. scan were compared to results obtained by angiography and nuclear scanning. In the diagnosis of multiple metastatic brain tumors. C.T. scans were superior to the other two procedures. however, C.T. scanning detected 4 lesions in the case of multiple meningiomas, while angiography disclosed 11 tumors in the same patient. In one patient having multiple gliomas, one (vascular) lesion only was demonstrated by angiography. Many other evaluations of Computerized Axial Tomography have been reported and the advent of this unique non-invasive radiologic technique has resulted in marked changes in the neuro-radiological diagnostic approach to brain tumors. However, it is important to recognize the weak as well as the strong points of each diagnostic procedure including the C.T. scan. At present, in our opinion, even with a positive demonstration of a brain tumor by C.T.scanning, cerebal angiography should be carried out prior to surgical intervention.

Brain Neoplasms↗