PubMed Health⌕ Search

Biomedical subjects

S Hojo

Publications and source records attributed to S Hojo.

64 records · Page 4Linked to original sources
PubMed1987

Metabolism of glycosylsucrose by oral microorganisms and its hydrolysis by Streptococcus salivarius fructosyltransferase.

Resting-cell suspensions of oral microorganisms grown in sucrose were studied for the production of acid from glucosylsucrose and maltosylsucrose. Most oral microorganisms fermented these sugars to only a limited extent. Streptococcus salivarius, however, metabolized glucosylsucrose as well as sucrose. We therefore looked for a specific enzyme in S. salivarius which was capable of hydrolyzing glucosylsucrose. Fructosyltransferase and invertase were purified from S. salivarius 13419, and the substrate specificities and hydrolytic activities of these enzymes were determined. Purified fructosyltransferase catalyzed fructan synthesis from glucosylsucrose or maltosylsucrose, whereas purified invertase barely hydrolyzed these sugars. These results suggest that the high fermentative efficiency of glycosylsucrose by S. salivarius is due to the hydrolysis of these sugars by fructosyltransferase, but not by invertase. The partially purified fructosyltransferases of Actinomyces viscosus NY1 and Streptococcus mutans NCIB 11723 catalyzed fructan synthesis from glucosylsucrose or maltosylsucrose. The fructosyltransferases of these oral microorganisms are also responsible for the hydrolysis of glycosylsucrose.

Actinomyces↗
PubMed1982

[Schmidt Ruppin-D-ASV-induced primary rat brain tumor model for therapeutic screening].

It is important to evaluate the therapeutic and side effects of new therapy for malignant brain tumors in an adequate animal model prior to its initial clinical investigation. For decades, neurooncologists have argued for the use of primary, autochthonous tumors rather than transplanted tumors such as C 6 glioma cells and 9 L gliosarcoma cells. But unfortunately, no spontaneous animal astrocytomas are currently available as usable models. So we tried to establish the model of primary, autochthonous avian sarcoma virus-induced rat gliomas for experimental chemotherapy and immunotherapy. The present study was undertaken to determine the incidence and histologic pattern of tumors and the mean survival time of the animal model used. It was found that the intracerebral inoculation of 2 X 10(6) FFU/5 microliter of infectious cell free homogeneous subgroup D Schmidt-Ruppin avian sarcoma virus (SR-D-ASV) into 3-day-old inbred Fischer 344 rats induced small sized tumors in all rats 20 days later. The mean survival time of inoculated rats were 58.7 +/- 12 days. As to the classification of SR-D-ASV induced brain tumors in Fischer rats, astrocytoma was 70.6% (protoplasmic astrocytoma 23.5%, fibrillary astrocytoma 47.1%), sarcoma 17.6%, and mixed astrocytoma and sarcoma 11.8%. In conclusion, this SR-D-ASV induced tumor in the rat fulfilled the following criteria for the desirable animal model: (1) Spontaneously arising. (2) Glial origin. (3) Intraparenchymal growth. (4) Uniformly fatal within reasonable time period. Statistic evaluation of the effects of chemotherapy and immunotherapy was considered to be possible.

Animals↗
PubMed1975

[Acute subdural hygroma in the posterior fossa (author's transl)].

Four cases of acute or subacute subdural hygromas in the posterior fossa were reported. All showed suboccipital skull fractures radiologically. Two cases of acute subdural hygromas were encounteded during the fiscal year from 1972 to 1973 at Toritsu Toshima Hospital. In the same period 254 patients with head injuries were admitted here and 106 demonstrated skull fractures. Among these 24 exhibited fractures in the suboccipital region. Among these 24 cases 8 showed signs and symptoms of space-occupying lesions in the posterior fossa and were confirmed later surgically (7 cases) or by autopsy (1 case), namely; three extradural hematomas, two acute subdural hygromas as mentioned above, three subdural hematomas with cerebellar contusions. Preoperative courses in these three acute subdural hygomas as well as three subdural hematomas were summarized as follows:lucid interval was followed by severe nuchal pain and rapid downhill course and finally by coma and panea. Retrograde brachial angiographies were performed in cases. The findings were not contributary to locate mass lesions, in three cases, partly because of delayed or faint filling of vessels caused by compression with hematoma or acute subdural hygroma. In short, differential diagnosis between subdural hematoma and subdural hygroma was difficult preoperating. Postoperatively, courses of subdural hematomas were poor or even fatal. On the contrary, patients of acute subdural hygromas showed rapid clinical improvement after evacuation of xanthochromic fluid. The authors stressed that suboccipital craniectomy should be performed as soon as possible to the patients with sugoccipital fractures when vital signs became progressively worse even if little findings were obtained by carotid angiographies. Subdural hygromas in the posterior fossa may have been present in those fatal cases where autopsy finds neither contusion nor hemorrhage but only brain edema or swelling.

Accidents, Traffic↗
PubMedDate not supplied

Primary undifferentiated carcinoma arising from the retroperitoneum: a case report.

A 35-year-old woman, gravida 1, para 1, underwent cesarean section in her 39th week of pregnancy. At the time of operation, multiple retroperitoneal tumors were found. Postoperative computed tomography and magnetic resonance imaging showed multiple solid tumors, each approximately 3-5 cm, in the right pelvic retroperitoneal space. Total resection of the tumors was performed without any macroscopic residual. A systematic workup for the primary tumor from which the retroperitoneal tumors may have metastasized failed to demonstrate any responsible tumor. We therefore assumed it to be a primary retroperitoneal tumor. The histopathologic features of the tumors were consistent with small-cell carcinoma. Two months postoperatively, recurrent tumors in the right inguinal and common iliac regions were detected. Since chemotherapy with irinotecan hydrochloride or paclitaxel did not produce any beneficial effect, a second tumor reduction surgery was performed 8 months after the initial operation. Four months after the second operation, a third operation including total hysterectomy, bilateral salpingo-oophorectomy, and tumor resection in the contralateral iliac region were done. Afterward, a new recurrent tumor appeared along the aorta up to the left supraclavicular node. The patient died 19 months after the first operation.

Adult↗
PubMedDate not supplied

Expression of oncofetal fibronectin and syndecan-1 mRNA in 18 human lung cancer cell lines.

It has been suggested that fibronectin (FN) and syndecan play an important role in many aspects of cell-substrate interactions including cell adhesion. We hypothesized that oncofetal FN (onfFN) and syndecan play an important role in the process of adhesion of several human lung cancer cell lines. To test this, levels of onfFN in the culture supernatant were measured by an enzyme-linked immunosorbent assay in 18 human lung cancer cell lines. In addition, expressions of onfFN and syndecan-1 mRNA were analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR). Of 18 lung cancer cell lines, 3 cell lines (all adenocarcinoma) released a significant amount of onfFN in culture supernatants. Of the 18 cell lines tested, 6 cell lines expressed a significant amount of mRNA for onfFN and 4 expressed a significant amount of mRNA for syndecan-1. Levels of onfFN and expressions of mRNA for onfFN and syndecan-1 were consistently higher in non-small cell lung cancer cell lines than in small cell lung cancer cell lines. In addition, cell lines that expressed mRNA for onfFN and syndecan-1 tended to adhere to culture dishes. Syndecan-1 expression was significantly higher in attached cells compared with nonattached cells within the same cell line. Differences in onfFN and syndecan synthesis may explain some in vitro and in vivo characteristics of lung cancer.

Cell Adhesion↗