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Biomedical subjects

N Shinohara

Publications and source records attributed to N Shinohara.

At least 145 records · Page 8Linked to original sources
PubMed1989

[Bacteriological investigation on an outbreak of acute enteritis associated with verotoxin-producing Escherichia coli O111:H-].

An outbreak of acute enteritis in children aged one to thirty-three months occurred from June 10th to 23rd, 1986, at a private orphanage in Matsuyama City. Twenty-two out of 23 children suffered from diarrhea. Nine of the 22 children excreted bloody stool. Fever and vomiting were observed with a few patients. One of them, a 33-month-old girl, developed hemolytic uremic syndrome, and died twelve days after the admission. Escherichia coli O111:H- was isolated from fecal specimens of 7 out of 15 patients. The culture filtrate of the isolate caused fluid accumulation in ligated ileal loops in a rabbit, and was lethal to mice. It was found that all isolates produced two kinds of Vero toxins (VT1 and VT2, or shiga-like toxin I and II). The amount of VT2 produced in vitro was about 10 times more than that of VT1.

Acute Disease↗
PubMed1989

[Infant botulism was confirmed in Ehime Prefecture].

The third case of infant botulism in Japan is reported. A four-month-old baby boy suddenly had weakness of suckling force, constipation and generalized hypotonicity. He was the product of normal gestation, labor and delivery. Growth and development were normal until he was nineteen weeks old. He received fruit-juice and honey daily. By bacteriological examination, Clostridium botulism type A was isolated from his feces and the honey which he had received. Type A toxin was detected from his feces but not from his serum.

Botulism↗
PubMed1989

[Effect of the resin-bonded restorations on the tooth displacement and the loading force of the supporting tissues].

A mechanical simulation model of tooth and alveolar bone was made and analyzed using three-dimensional finite element technique. And the variations of tooth mobility and the periodontium supporting force caused by the absorption of alveolar bone was investigated. The results obtained were as follows: 1. When the physiological tooth mobility was 150 microns, the teeth were sufficiently fixed using the resin-bonded splint and bridge connected with more than three teeth in the case of 40 percent of alveolar bone absorption. However in the case of 60 percent of alveolar bone absorption, the teeth were not fixed with splint and bridge of six teeth connections. 2. In the application of resin-bonded splint and bridge, when the metal frame thickness was 0.5 mm, the effect of the connected place on tooth mobility was large, and the abutment teeth were sufficiently fixed when the abutment teeth were connected up to the neck. 3. The periodontium supporting force decreased markedly according to the increase of abutment teeth. 4. When the abutment teeth were less than five teeth, the inhibitory action for tooth mobility of the resin-bonded splint and bridge was widely different, and resin-bonded splint was more effective compared with bridge.

Alveolar Bone Loss↗
PubMed1989

[The effect of the cementing material on the strength of the all ceramic crown].

On the assumption that the all ceramic crown was cemented on an abutment tooth, the effect of the cementing materials on the strength of the ceramic crown was analyzed using two-dimensional finite element technique. The results obtained were as follows: 1. When the compressive load was applied to the ceramics, the principal stress in the cementing material was compressive in the region of Young's modulus of the cementing materials 200-700 kg/mm2, but was in tension beyond it. 2. When the tensile load was applied to the ceramics, the principal stress in the cementing material was in tension, and decreased as Young's modulus of the cementing materials decreased. 3. When the adhesive effect of the cementing material was investigated with examining the presence of the crack between the ceramics and the cementing material, the principal stress in the ceramics increased as the crack propagated. 4. The creation and propagation of the crack, the increase of the principal stress in the ceramics and the destruction of the ceramics were suggested. 5. When the analyzed results were compared with the mechanical properties of the cementing materials from the point of view of the breaking strength, it was considered that the adhesive resin cement was favorable as the cementing material of the ceramic crown. And the Young's modulus of the adhesive resin cement was about 400 kg/mm2.

Crowns↗
PubMed1989

[Effect of the 3/4 crown and porcelain-fused crown restorations on the tooth displacement and the loading force of the supporting tissues].

A mechanical simulation model of tooth and alveolar bone in the application of 3/4 crown and porcelain-fused crown restorations was made and analyzed using three-dimensional finite element technique. The results obtained were as follows. 1. When the physiological tooth mobility was less than 150 microns, the teeth were sufficiently fixed using the splint and the bridge connected with more than two teeth, in the case of 20 percent absorption of the alveolar bone, and more than three teeth in the case of 40 percent absorption. In the case of 60 percent absorption, the teeth were fixed with the splint of six teeth connections, and were fixed with the bridge of five teeth connections. 2. The periodontium supporting force decreased markedly according to the increase of the number of the abutment teeth. 3. The teeth accompanied with the absorption of the alveolar bone were connected, in order to inhibit the tooth mobility and the periodontium supporting force. In this application, it had the inhibitory action when the replacing ratio of metal and ceramics to a crown of the tooth was less than 35 percent. 4. According to the finite element analysis, the design bases of fixed restorations applied in the teeth accompanied with the absorption of the alveolar bone were preferred.

Alveolar Bone Loss↗
PubMed1989

[Massive bone allografts in large bone defects after tumor surgery: a clinical long-term study].

Eleven patients with malignant bone tumor arising in femur and tibia treated by means of bone graft were followed for 25 months to 6 years. Histological diagnosis included 8 osteosarcomas, a chondrosarcoma, a malignant fibrous histiocytoma and a round-cell sarcoma. They had intensive adjuvant chemotherapy for a year after the operation. The drugs used were adriamycin and high-dose methotrexate. One patient died of pulmonary metastasis, two patients of local recurrence and another patient of infection requiring amputation. Seven cases were finally evaluated. Of these 7 cases, operative procedures included one segmental femoral resection with intercalary allograft, two segmental femoral resections with allograft and knee arthrodesis, three segmental tibial resections with allograft and knee arthrodesis and one eccentric resection of femur with allograft. There were three allograft resorptions which were successfully treated by additional autografts. Other complications were a septic fistula formation and two cases of breakage in internal securing metals due to non-union. They also healed without further problem. Bone healings of the grafts were evaluated on X-ray and one case was histologically examined. All of the primary segmental allografts after the wide resection of the tumor failed in the primary bone healing. However, additional autogenous bone graft led to healing within two years. Functional evaluation according to Enneking proved good in four and fair in three cases. Reconstructive surgery with massive bone grafts represents a successful alternative to prosthetic implant in young adults with long life expectancy.

Bone Neoplasms↗
PubMed1989

[Testicular metastasis of multiple myeloma: a case report].

A 49-year-old man was admitted to our department with the complaint of right scrotal painless swelling in May 1986. The patient had been treated for multiple myeloma since November 1985. Right orchiectomy was performed under the diagnosis of malignant testicular tumor. The right scrotal mass was 5 x 7.5 x 3.5 cm in size. Histological diagnosis was testicular metastasis of multiple myeloma. Testicular metastasis of multiple myeloma is very rare and only 5 cases have been reported in the Japanese literature. The 6 cases including our case with testicular metastasis of multiple myeloma in Japan are reviewed.

Humans↗
PubMed1989

Prosthetic replacement due to giant-cell tumor in the proximal humerus. A case report.

A 45-year-old woman with an extensive giant-cell tumor of the right proximal humerus was treated by segmental resection and shoulder reconstruction. A Neer prosthesis and allogeneic bone grafts were used to reconstruct the shoulder joint. Autogeneic iliac bone was placed at the host-graft junction. The rotator cuff was reattached to the bone after making a semicircular trough. The long head of the biceps was reattached with stay sutures after making a trough between reattachments of the supraspinatus and the subscapularis. The patient regained almost full range of motion and excellent muscle power of the shoulder 60 months after operation. She did not have any difficulty with daily tasks of living. The prosthesis articulated with the glenoid well. There has been no evidence of tumor recurrence or metastasis.

Bone Neoplasms↗
PubMed1988

Killing of antigen-reactive B cells by class II-restricted, soluble antigen-specific CD8+ cytolytic T lymphocytes.

Cytolytic T lymphocytes (CTLs) are generally thought to recognize cellular antigens presented by class I MHC molecules. A number of studies, however, have revealed responses of considerable magnitude involving both CD8+ and CD4+ CTLs with class II restriction, suggesting that class II-restricted CTLs recognizing exogeneous protein antigens may exist. As class II antigens are normally expressed on limited types of cells such as B cells and macrophages, such CTLs might be expected to exert a suppressive effect on antibody responses. Here we report that stimulation of mouse lymphocytes with a soluble antigen induced CD8+ and CD4+ CTLs specific for the antigen with class II restriction. The specific lysis was far more efficient when target B cells specifically recognized the antigen than when they did not, indicating that the primary targets for these CTLs are probably B cells expressing immunoglobulin receptors reactive for the same antigen molecule. These results suggest that the natural occurrence of such CTLs during immune responses may explain antigen-specific suppression on antibody responses by T cells.

Animals↗
PubMed1988

Class II antigen-specific murine cytolytic T lymphocytes (CTL). II. Genuine class II specificity of Lyt-2+ CTL clones.

Class II-specific allogeneic cytolytic T lymphocytes (CTL) consist of two types of cells, i.e., Lyt-2+L3T4- and Lyt-2-L3T4 T cells. The Lyt-2+L3T4- class II-specific CTL population constitutes a conspicuous exception to the general correlation observed between the class of major histocompatibility complex antigen recognized and the type of accessory molecules expressed by T cells. In order to examine the specificity of such an exceptional T cell population, CTL clones were established by limiting dilution of a bulk CTL line developed in an I region incompatible combination of mouse strains, B10.QBR anti-B10.MBR. These CTL lines showed single genetic specificity indicating their clonal nature with respect to CTL activities. Lyt-2+L3T4- (2+4-), Lyt-2-L3T4+ (2-4+) and Lyt-2-L3T4- (2-4-) clones were obtained. Among many CTL clones showing a spectrum of genetic specificities, 2+4- and 2-4+ clones with apparent I-Ak-specificity, were studied further and four lines of evidence confirmed their class II specificity: 1) genes encoding the target antigen for these CTL clones were mapped within the I-A subregion by simple genetics; 2) an I-Ak-specific monoclonal antibody readily blocked specific cytolysis by these clones; 3) the clones failed to react with cells expressing mutated I-Ak antigens; and 4) a B cell tumor transfected with alpha- and beta-chain genes of I-Ak was specifically lysed by these CTL clones. These data therefore establish the existence of Lyt-2+ CTL with genuine class II specificity. All 2-4+ CTL were sensitive to the blocking effect of an antibody to L3T4, whereas none of the 2+4- class II-specific CTL were sensitive to blocking by an anti-Lyt-2 antibody, indicating that class II-specific CTL with "wrong phenotype" is not dependent on the function of the accessory molecule. Besides true class II-specific CTL clones, 2+4- clones with a spectrum of genetic specificities were obtained, including clones recognizing a combination of an I-Ak product and the Kb molecule. Two 2-4- clones were also specific for the combination of Kb + I-Ak. These clones most likely recognize an allogeneic class II antigen in the context of a class I antigen and therefore would more appropriately be included in the class I-restricted T cell population.

Animals↗
PubMed1988

Topological analysis of the three-dimensional structure of the human renal glomerulus using a computer-aided reconstruction system.

A quantitative topological analysis of human renal glomerular capillaries reconstructed from serial sections was performed with the aid of a computer system. The peripheral portions of five glomeruli from each of the subcapsular, midcortical, and juxtamedullary zones were reconstructed, each portion corresponding to about one-sixth the diameter of a glomerulus. Statistically, there was no significant difference in the cycle rank (number of independent cycles) of the glomerular capillary network per unit volume of glomerular capillaries or Bowman's capsule among the three renal zones. It was proved that, irrespective of the location of the glomerulus, the glomerular capillary network possessed a larger cycle rank as the volume of the glomerular capillaries or Bowman's capsule increased. This finding strongly suggests that the mean cycle rank per single glomerulus is largest in the juxtamedullary zone.

Capillaries↗
PubMed1988

Osseous xanthomatosis and a pathologic fracture in a patient with hyperlipidemia. A case report.

Osseous xanthomatosis and a pathologic fracture of the femoral neck associated with hyperlipoproteinemia occurred in a 48-year-old woman. Widely distributed skeletal lesions suggested a primary neoplasm such as malignant lymphoma or multiple myeloma; however, needle aspiration cytology of the fracture site, cutaneous manifestations, and abnormally high concentrations of lipoproteins established a diagnosis of intraosseous xanthomatosis associated with hyperlipidemia. Histologically, the excised femoral head showed a dense aggregate of lipid-laden macrophages and depletion of normal bone trabeculae. The hyperlipidemia is classified as Type IIb hyperlipoproteinemia.

Bone Diseases↗
PubMed1988

[Evaluation of adjuvant chemotherapy of osteosarcoma with special reference to adriamycin (final report)].

Adjuvant chemotherapy mainly with ADR performed in 117 patients (pts) with primary osteosarcoma of the extremity for the purpose of preventing pulmonary metastasis after radical ablative surgery. The mean follow-up period for 117 pts was 51.7 months (range: 3 to 137), for 53 survivors, 90.1 months (range: 60 to 137) and for 64 decreased, 20.5 months (range: 3 to 73). ADR was administered intravenously with 0.6-0.8 mg/kg/day for 3 consecutive days at monthly intervals after surgery until reaching 600 or 500 mg/m2 of the total cumulative dose. Five-year overall and disease-free survival rate of all pts was 50.2% and 39.4%, respectively. Thirty-seven pts (multi-drug group) with the combination of ADR and HDMTX had a higher survival rate (63.1% in 5-year overall survival rate and 47.8% in 5-year disease-free survival rate) than that of 80 pts with ADR alone (ADR group) (44.4% in 5-year overall survival rate and 35.6% in 5-year disease-free survival rate). Five-year survival rate for 65 pts administered the greater than 500 mg of ADR was 59.3% compared to 36.9% for 52 pts the less than 500 mg (p less than 0.05). In 65 pts administered the greater than 500 mg of ADR, 5-year survival rate (76.5%) of the multidrug group (17 pts) showed superiority to that 52.1%) of the ADR group (48 pts) (p less than 0.01). Even in the multi-drug group, 5-year survival rate (76.5%) of 17 pts administered the greater than 500 mg of ADR was higher than that (41.3%) of 20 pts given the less than 500 mg (p less than 0.01). Distant metastases were recognized at lung in 52 pts (lung group), lung + extrapulmonary organs in 14 (+ extragroup), and only extrapulmonary organs in 3 (extra group). Five-year survival rate of 66 pts with pulmonary metastasis was 17.1% and 21.2% in the lung group compared with 0% of the extra group (P less than 0.01). Five-year survival rate for 23 pts treated with thoracotomy was 43.5% compared to 2.6% for 43 without it (p less than 0.01).

Adolescent↗
PubMed1987

Role of accessory molecules in signal transduction of cytolytic T lymphocyte by anti-T cell receptor and anti-Ly-6.2C monoclonal antibodies.

Accessory molecules present on the cell surface of cytolytic T lymphocytes (CTL) play an important role in their activation. Antigen-specific recognition by CTL is inhibited by antibodies against Lyt-2, L3T4, or LFA-1 molecules. Presently it is not known whether these molecules function by binding a ligand such as class I or class II on the target cell or by delivering a signal that down-regulates T cell activation. In the present study we utilized anti-T cell antibodies including anti-T3 and anti-T cell receptor (alpha/beta) as well as an anti-Ly-6.2C monoclonal antibody to activate CTL clones to kill irrelevant targets or secrete BLT esterase. The redirected lysis assay system utilizes the fact that heteroconjugates between anti-T3, and anti-T cell receptor, or anti-Ly-6.2C and anti-trinitrophenyl can trigger CTL lysis of trinitrophenyl-coupled targets that did not express antigen. In this system anti-Lyt-2 antibodies as well as anti-LFA-1 antibodies inhibited triggering via T cell receptor-related molecules but not via the anti-Ly-6.2C heteroconjugate. In addition, the anti-Lyt-2 was shown to inhibit conjugate formation in the heteroaggregate assay system suggesting that the anti-Lyt-2 antibodies acted early in inhibiting CTL activity. Similar results were observed in a system in which the CTL clones were triggered to secrete a BLT-esterase-like activity in the absence of target cells. Anti-T3 coated on plastic was shown to activate BLT-esterase secretion. This secretion was inhibited by anti-Lyt-2 and anti-LFA-1. Thus, it would appear that both the Lyt-2 molecule and the LFA-1 molecule act as signal-transducing elements involved in CTL activation. In particular, the Lyt-2 molecule appears to preferentially function in receptor-mediated T cell activation.

Animals↗
PubMed1987

Class II antigen-specific murine cytolytic T lymphocytes (CTL). I. Analysis of bulk populations and establishment of Lyt-2+L3T4- and Lyt-2-L3T4+ bulk CTL lines.

Murine allogeneic cytolytic T lymphocytes (CTLs), including long-term bulk CTL lines, were induced in I-region-incompatible combinations of strains in vitro in order to study the phenotypes of class II major histocompatibility complex (MHC) antigen-specific CTLs, as well as the possible functional involvement of accessory cell interaction molecules such as Lyt-2 and L3T4. This report shows that class II-specific allogeneic CTL populations consist of two types of T cells. Lyt-2+L3T4- (2+4-) and Lyt-2-L3T4+ (2-4+), in variable proportions depending on the strain combination, that in vitro bulk CTL lines with each of these phenotypes can be established, that the killing function of 2-4+ CTL is sensitive to the blocking effect of anti-L3T4 antibodies, suggesting functional involvement of this molecule in the CTL-target interaction, that anti-Lyt-2 antibodies fail to block killing by 2+4- cells, suggesting that such CTLs do not utilize this molecule in their killing function, and that while I-A-specific CTLs of both phenotypes are detectable, 2-4+ cells could not be detected among I-E-specific CTL populations.

Animals↗
PubMed1987

[Treatment of malignant fibrous histiocytoma of soft tissues].

Thirty-six patients with soft tissue malignant fibrous histiocytoma were followed up. At the time of this study, 14 of the 36 patients were alive and the average follow-up period was 59.3 months. The average age at initial diagnosis was 62.1 years. Of the 36 patients, 13 were initially treated by us. All of the marginal excision cases (17) showed recurrence. Five of 8 additional excision cases had residual tumor and three of these showed recurrence. Those cases given primary wide excision (5) showed no local recurrence. One out of 3 amputation cases showed recurrence five years after the operation. Thus, the total recurrence rate was 64%. The average period of recurrence was 9.3 months (n = 21). Radiotherapy was effective in four patients among 11 irradiated cases. Chemotherapy is difficult to apply, since patients are generally too old to tolerate intensive chemotherapy and also the drug-sensitivity is low. For this reason, we have insufficient clinical experience to make an evaluation. Five-year survival rate was 45% and 10-year survival, 30%. Early detection of the tumor and adequate initial surgery are the best ways of improving the results of treatment for MFH. Chemotherapy and radiotherapy might achieve adjuvant effects and produce better results.

Adult↗