Biomedical subjects

S Yoshimura

Publications and source records attributed to S Yoshimura.

At least 19 recordsLinked to original sources

PubMed2025

Impact of Chewing Behavior Change on Cognition and Cerebral Hemodynamics.

BACKGROUND: Impaired chewing ability is a recognized risk factor for cognitive decline in older adults, potentially due to reduced neural stimulation in cognition-related brain regions. While short-term studies have demonstrated transient increases in neural activity from chewing, the sustained cognitive and neurophysiological effects of encouraging thorough chewing habits in daily life remain unclear. OBJECTIVE: This randomized controlled trial investigated whether promoting thorough chewing during meals could improve cognitive function and cerebral hemodynamics in older adults. METHODS: Fifty participants aged 65 y or older were randomly assigned to either a 1-mo intervention group, which used a wearable device to monitor and increase chewing strokes during meals, or a control group that maintained usual chewing habits. Chewing behavior, cognitive performance (including memory and executive function via the color Stroop test), and cerebral hemodynamics in the dorsolateral prefrontal cortex (DLPFC) were measured at baseline and after 1 mo. Statistical analyses included t tests, chi-square tests, 2-way analysis of variance with post hoc tests, Pearson correlations, and generalized linear models to evaluate group differences and associations between chewing and cognitive outcomes. RESULTS: Significant time-by-group interactions were observed for memory, F(1, 48) = 6.24, P = 0.043, and hemodynamic responses in the left DLPFC, F(1, 48) = 6.19, P = 0.013. The intervention group showed increased chewing frequency (P = 0.017), improved memory performance, and reduced left DLPFC responses compared with controls. Chewing frequency was positively correlated with Stroop test scores (r = 0.53, P = 0.010) and negatively with hemodynamic changes in the left DLPFC (r = -0.30, P = 0.040). Although improvements in other cognitive outcomes and hemodynamic measures favored the intervention group, these differences did not reach statistical significance. CONCLUSIONS: Promoting intentional chewing habits for 1 mo may enhance memory-related cognitive performance and neural efficiency in the DLPFC during working memory tasks in older adults. This nonpharmacologic, low-burden strategy warrants further research with longer interventions to support cognitive health and dementia prevention. TRIAL REGISTRATION ID: UMIN000044280Knowledge Transfer Statement:This study demonstrates that promoting thorough chewing habits in older adults can improve memory and enhance neural efficiency in the brain. Encouraging intentional mastication is a simple, nonpharmacologic approach that may help maintain cognitive health and prevent dementia, providing a practical strategy for clinicians and policymakers to support healthy aging.

Humans↗

PubMed1992

Effect of tumor size on the enhancement by gamma interferon of the localization of radiolabeled F(ab')2 fragments of anti-intercellular adhesion molecule-1 monoclonal antibodies in human colon carcinoma cells grafted in nude mice.

Because tumor size has been shown to influence the specific accumulation of radiolabeled anti-tumor-associated antigen monoclonal antibodies (mAb), the present study has investigated the effect of the tumor size on the enhancement by gamma interferon (IFN-gamma) of the accumulation of radiolabeled mAb in malignant lesions. Intercellular adhesion molecule-1 (ICAM-1) has been used as a marker because of its high susceptibility to modulation by IFN-gamma. F(ab')2 fragments of anti-ICAM-1 mAb CL207.14 have been selected to visualize malignant lesions, because they had been shown to be more sensitive probes for our experiments than whole IgG. Administration of IFN-gamma to human colon carcinoma-bearing nude mice increased the expression of ICAM-1 in the xenografts and the specific accumulation of 125I-F(ab')2 fragments of anti-ICAM-1 mAb CL207.14. The latter effect is influenced by the size of the lesions, because it was observed only in tumors with an approximate diameter of 8 mm and an approximate weight of 250 mg. If these results obtained in an animal model system are applicable to patients with malignant diseases, the present investigation suggests that administration of IFN-gamma enhances the sensitivity of immunoscintigraphy and the efficacy of immunotherapy with radiolabeled mAb which recognize tumor-associated antigens that are susceptible to modulation by IFN-gamma. However, the effect of IFN-gamma is not a general phenomenon but is influenced by the size of the malignant lesions.

Animals↗

PubMed1992

Clinical significance of the epidermal growth factor receptor gene in squamous cell carcinomas of the nasal cavities and paranasal sinuses.

The authors retrospectively analyzed epidermal growth factor receptor (EGFR) gene amplification in 49 cases of squamous cell carcinoma (SCC) arising from the nasal cavities (NC) and paranasal sinuses (PS) by using slot-blot analysis of DNA extracted from formalin-fixed, paraffin-embedded tissues. Also, the relationship between the results of gene analysis and the clinical features of the patients was studied to investigate the clinical significance of the EGFR in SCC of the NC and PS. Amplification of the EGFR gene was detected in 5 of the 49 cases (10%). No significant difference was observed between EGFR gene amplification and the presence of lymph node metastases, local recurrence, or prognosis. This suggests that EGFR gene amplification is not related to the local progression or metastasis of the SCC in the NC and PS. In addition, it appears that amplification of the EGFR gene is not a prognostic indicator for SCC in the NC and PS.

Adult↗

PubMed1992

The postoperative recurrence of Crohn's disease: an analysis of 37 patients with Crohn's disease who underwent endoscopy during initial surgery.

A total 37 patients with Crohn's disease who underwent intraoperative endoscopy during resection of the affected intestine were evaluated in this study. The average age of the patients at surgery was 23.2 years. The residual lesions in the remaining intestine identified by intraoperative endoscopy were classified according to their pathologic profiles into three groups: A, B and C. In group A, comprising patients with longitudinal ulcers and/or a cobblestone appearance, 10 of 12 patients had recurrence. In 5 of these 10, the residual lesions were exacerbated and 2 required a further operation. The remaining 5 patients showed recurrence at the site of previous anastomosis and 2 of these 5 required additional surgery. In group B, comprising patients with small ulcers, aphthoid ulcers, or scars, and group C, comprising patients with no residual lesions, recurrence was observed in 13 of 16, and 3 of 9 patients, respectively. The recurrent lesions were all found proximal to, or at the site of previous anastomosis. Additional operations were performed on 3 of the group B patients. The findings of this study revealed that recurrence requiring additional surgery is more frequent at the site of anastomosis, regardless of the endoscopic appearance of the residual lesions.

Adolescent↗

PubMed1992

Central neurocytoma presenting with gigantism: case report.

We report a case of central neurocytoma presenting with gigantism. The patient was a 19-year-old man with a 2-year history of rapid growth. Computed tomography revealed a round, slightly enhancing calcified tumor in the septal region. This lesion was resected, and postoperative radiotherapy was given. The preoperative serum growth hormone level was 20.7 ng/mL, and postoperatively this fell to 0.9 ng/mL. Pituitary dysfunction was not noted either before or after the operation. A low level of production of growth hormone releasing factor was detected when tumor cells obtained during surgery were cultured.

Adult↗

PubMed1992

Production and characterization of two monoclonal antibodies to human glutathione peroxidase.

Glutathione peroxidase (GSH-Px) is an important selenium-containing enzyme which protects cells from oxidative damage. Two hybridoma clones (GPX-121 and GPX-347), producing mouse IgG1 monoclonal antibodies specific for GSH-Px, were established. Immunoblot analysis revealed that GPX-347 was specific for human GSH-Px, while GPX-121 cross-reacted with human, rat, mouse and rabbit GSH-Px. Correlation between GSH-Px content and its enzymatic activity was investigated in erythrocytes of 76 humans and in human lung adenocarcinoma PC-9 cells by using a sandwich type ELISA. The results indicated that GSH-Px activity was expressed higher than expected from GSH-Px content especially in the range of low GSH-Px concentration. PC-9 cells selenium depleted medium did not stain but the cytoplasm of PC-9 cells grown in medium supplemented with selenium stained strongly.

Adenocarcinoma↗

PubMed1992

The inhibitory effect of the combination of antineoplaston A-10 injection with a small dose of cis-diamminedichloroplatinum on cell and tumor growth of human hepatocellular carcinoma.

The inhibitory effects of a combination of Antineoplaston A-10 Injection with a small dose of cis-diamminedichloroplatinum (CDDP) on cell and tumor growth was tested in vitro and in vivo settings. A human hepatocellular carcinoma cell line (KIM-1) was used for the cell growth and transplanted tumor growth studies. In the cell growth study, one-hour exposure of KIM-1 cells to CDDP in the medium at concentrations of 0.5, 1.0, and 2.0 micrograms/ml inhibited cell growth dose-dependently. Continuous exposure of cultured cells to Antineoplaston A-10 Injection at concentrations of 4, 6, and 8 mg/ml also inhibited tumor growth dose-dependently. The combination of 0.5 microgram/ml CDDP and 6 mg/ml A-10 Injection inhibited cell growth more than did each agent individually. Electron microscopic study showed well-maintained organelle structures in Antineoplaston A-10 Injection-treated cells compared to CDDP-treated cells. alpha-Fetoprotein (AFP) production by 10(4) cells in 48 h increased in the A-10 Injection-treated and A-10 Injection+CDDP-treated groups as the concentration of these agents increased. In the tumor growth study, daily administration of Antineoplaston A-10 Injection 75 mg with once a week administration of 20 micrograms of CDDP for 5 weeks inhibited transplanted tumor growth in athymic mice after 33 days of treatment, while administration of 75 mg of A-10 Injection or 20 or 60 micrograms of CDDP alone showed no significant inhibition of tumor growth.

Animals↗

PubMed1992

Analysis of urinary protein by immunoblot method using unconcentrated urine in preeclampsia.

In order to investigate the renal change in preeclampsia, molecular weight and specific protein analyses in unconcentrated urine were performed by the immunoblot method. Urine samples were taken from 34 preeclamptic cases (pure type), including 20 severe cases. Polypeptide profiles of urine consisted of four patterns: low MW (L) pattern (tubular damage), high MW (H) pattern (glomerular damage), high and low MW (HL) pattern, and middle MW (M) pattern. The incidences of the HL, H, L, and M patterns were 26.5%, 14.7%, 11.8%, and 47.1%, respectively. The HL pattern was found more frequently in severe proteinuria than in mild proteinuria. High incidences of the HL and H patterns were found in the hypertensive group. Larger amounts of IgM, fibronectin, IgG, and beta 2 microglobulin in urine were confirmed using specific antibodies. Our results suggest that the immunoblot method makes it possible to differentiate glomerular and tubular damages and to evaluate the severity of renal damage in preeclampsia using unconcentrated urine.

Female↗

PubMed1992

[A fifty two-week oral repeated dose toxicity study of suplatast tosilate (IPD-1151T) in dogs].

A 52-week oral repeated dose toxicity study of suplatast tosilate (IPD-1151T), a newly developed anti-allergic agent, was carried out in beagles by oral administration of 30, 90, 270 and 810 mg/kg/day for 52 weeks. The recovery study was carried out by the withdrawal for 5 weeks using control and the 810 mg/kg groups. The results are as follows: 1. Observation of general conditions revealed soft feces, mucous feces, and diarrhea in both sexes of the 270 and 810 mg/kg groups during the administration period, and these findings disappeared during the withdrawal period. One female of the 810 mg/kg group exhibited tremors in the legs and neck, staggering, a decrease of spontaneous motor activity, and clonic convulsions in Week 17 of administration and died on Day 118. One male of the same group exhibited whole body tremors and staggering from Week 32 to Week 52. 2. Body weight gain tended to be inhibited in males of the 810 mg/kg group during the administration period. The body weight of the female that died decreased rapidly after the appearance of neurological symptoms. The body weight of the male that exhibited neurological symptoms decreased after their appearance but later increased. 3. There were no abnormal changes in food consumption in all of the sacrificed dogs. The female that died did not eat at all after the appearance of neurological symptoms. The male that exhibited neurological symptoms did not eat at all for 1 week after their appearance, but the food consumption returned to normal thereafter. 4. Prothrombin times were prolonged in males of the 270 and 810 mg/kg groups at Week 26, and activated partial thromboplastin times were prolonged in males of the 810 mg/kg group at Week 52. 5. Plasma levels of alkaline phosphatase, GPT and LDH were elevated in some males and females of the 810 mg/kg groups. 6. No abnormalities due to IPD-1151T administration were found in urinalysis, opthalmological examination, electrocardiography, and fecal occult blood examination, or organ weights. 7. Autopsies including histopathological and electron microscopic examinations on the sacrificed dogs revealed no abnormalities. Subserosal hemorrhage in the base of the heart, congestion in the lungs, congestion and vacuolation in the liver and slight cell infiltration around vessels of the brain were found in the female that died.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗

PubMed1992

Suprasellar malignant teratoma with 11-year survival--case report.

Long-term survival of malignant teratoma is rare. A 16-year-old female with a suprasellar malignant teratoma survived for 11 years before succumbing to embryonal carcinoma. A suprasellar immature teratoma with increased serum alpha-fetoprotein level was verified histologically. Radiation therapy and combined chemotherapy were given after partial removal. Eleven years later, the primary lesion recurred as embryonal carcinoma.

Adolescent↗

PubMed1992

Quantification of the c-myc gene in gastric carcinomas by the triplex polymerase chain reaction and high performance liquid chromatography.

The triplex polymerase chain reaction (PCR) and high performance liquid chromatography (HPLC) techniques were used to examine the state of amplification of the c-myc gene in gastric carcinomas. Sequences from the c-myc gene and from the two control genes were coamplified by PCR. The coamplified PCR products were separated and quantified by HPLC and the copy numbers of the c-myc gene were calculated by comparing the peak areas generated by PCR products. Increased copy numbers of the c-myc gene were found in 2 of 5 patients.

Chromatography, High Pressure Liquid↗

PubMed1992

Isolation of a new human pseudogene for proliferating cell nuclear antigen.

A new gene, which cross-hybridized with a rat PCNA cDNA probe, has been isolated from a human genomic cosmid library. A comparison of the gene with the human PCNA cDNA revealed 71% homology for the nucleotide sequences. This gene completely lacks introns and has traces of a polyA tail which the messenger RNA of the active gene retains. These facts indicate that this gene was generated by the reverse-transcription of a processed RNA for PCNA and exists as a PCNA pseudogene in the human genome.

Animals↗

PubMed1992

[Brief counting method of airborne Cryptomeria japonica pollen by a combination of fluorescence antibody staining and flow cytometry].

Airborne pollens collected in a pollen collector (Virtual Impactor) was treated with a fluorescein isothiocyanate-labeled monoclonal antibody (KW-S10) which was strictly specific to Japanese cedar pollen antigen (Cry j I). Flow cytometric analysis revealed that the intensity of fluorescence of the pollen samples treated with the antibody was greater than that of non-treated reference pollen or the antibody treated Hinoki-cypress pollen. By use of this method, it may be possible to display the airborne pollen concentration within 20 min after sampling.

Air↗

PubMed1992

[Clinical studies on tosufloxacin (TFLX) in urology].

We clinically evaluated the usefulness of a new oral antimicrobial agent, TFLX, in the field of urology. The dose administered was 150 mg t.i.d and the duration of administration was 3 days. The clinical effect was evaluated according to the criteria of the Japanese UTI committee. The clinical response obtained on 164 female patients with acute simple cystitis was excellent in 118, moderate in 44 and poor in 2 patients. The efficacy rate was 98.78%. The clinical response obtained on 4 male patients with acute simple cystitis was excellent in 2 and moderate in 2 patients. The efficacy rate was 100%. The clinical response obtained on 3 female patients with simple pyelonephritis was excellent in 2 and moderate in 1 patient. The efficacy rate was 100%. The clinical response obtained on one patient with non-gonococcal urethritis was excellent by doctor's evaluation. The clinical response obtained on 7 patients with complicated UTI was excellent in 3 and moderate in 4 patients. The efficacy rate was 100%. Three patients complained of stomach distress or malaise and 2 patients developed rash. No abnormal laboratory data were observed. Thus, TFLX appears to be safe and suitable for use in the field of urology.

4-Quinolones↗

PubMed1992

[Peripheral aneurysms of the posterior inferior cerebellar artery; analysis of 15 cases].

Peripheral aneurysms of the posterior inferior cerebellar artery (PICA) are rare. The authors report 15 cases of peripheral PICA aneurysms. Twelve of the aneurysms were discovered after their rupture and two were discovered after rupture of concomitant AVM, and one was detected incidentally. As to the location of aneurysms, more than half of the aneurysms arose at the telovelotonsillar segment. One patient had 2 aneurysms on the same peripheral PICA, which were not obvious on preoperative angiography because the ruptured one was partially thrombosed. Another rare case with aneurysm located at the internal auditory meatus is also reported. The findings of CT were characteristic, namely hemorrhage in the fourth ventricle without obvious hemorrhage in the basal cisterns, or only within the cerebellar vermian cistern. This phenomenon strongly suggested the possibility of rupture of peripheral PICA aneurysms. As to the surgical results, 10 patients (71%) of the 14 patients had a good recovery, and 1 patient (7%) with nonrupture aneurysm had a fair result due to pre-existing pontine hemorrhage. Three patients (21%) died. Rebleeding occurred in 3 patients, but cerebral vasospasm occurred in only 1 patient. Consequently, as peripheral PICA aneurysms are likely to be missed, and rebleeding is an unfavorable factor, one should try to demonstrate aneurysms with angiography, by using various methods such as subtraction or magnification.

Adolescent↗

PubMed1991

Effects of various mucosal protective drugs on diethyldithiocarbamate-induced antral ulcer in rats.

This study was designed to determine the effects of exogenous Cu,Zn-superoxide dismutase (SOD) and various mucosal protective agents against antral ulcer induced by diethyldithiocarbamate (DDC), inhibitor of Cu,Zn-SOD. Exogenous Cu,Zn-SOD reduced ulcer formation and prevented a decrease in SOD activity in gastric mucosa. This result indicates that maintenance of mucosal SOD activity is essential to prevent the ulcerogenicity of DDC. Many mucosal protective drugs that increase blood flow, mucus secretion, and endogenous prostaglandin failed to prevent ulcer formation and decrease of mucosal SOD activity. Rebamipide, however, significantly reduced ulcerogenesis and maintained mucosal SOD activity. This suggests that rebamipide has new protective effects on gastric mucosa.

Alanine↗

PubMed1991

Hydrogen peroxide generation by eosinophils in allergic rhinitis.

It was the aim to study the hydrogen peroxide (H2O2) generation by eosinophils in allergic rhinitis caused by house dust which was examined in nasal secretion and peripheral blood. The concentration of H2O2 in nasal secretions was increased after nasal challenge with house dust, and subsided gradually by the increase of peroxidase activity. The population of eosinophils and H2O2 generation which was morphologically detected on the plasma membrane of eosinophils in nasal secretion, were increased with the release of eosinophil chemotactic activity after nasal challenge. Also, in peripheral blood, the number and phagocytic activity of eosinophils in extremely high density 1.102 g/ml were increased after nasal challenge. A high number of eosinophils was found in a density of 1.097 g/ml in the high IgE group, but showed less phagocytic activity than in the lower IgE group. Considering from these findings, H2O2 generation by eosinophils appeared to be an important event in tissue injury and augmentation of allergic reaction.

Adolescent↗

PubMed1991

Tissue specific expression of the plasma glutathione peroxidase gene in rat kidney.

Rat plasma glutathione peroxidase (GSH-Px) was purified 1,400-fold from rat serum by a combination of phenyl Sepharose, DEAE Sephacel, blue Sepharose and Sephacryl S-200 column chromatographies. The purified GSH-Px migrated as a single band corresponding to a molecular weight of 22,500 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme was used for the immunization of chickens to obtain a specific antibody and for determination of its amino acid sequence. Two overlapping cDNA clones for rat plasma GSH-Px were isolated from a placental cDNA library. The composite nucleotide sequence is 1,529 base-pairs long and encodes 226 amino acids. The deduced amino acid sequence completely coincided with the sequences of five individual peptide fragments derived from the purified plasma GSH-Px on digestion with lysyl endopeptidase. In order to identify the tissue(s) generating this plasma GSH-Px, immunoblot analysis was performed on homogenates prepared from 13 tissues. A single immunoreactive band of 22.5 kDa, corresponding to plasma GSH-Px, was detected for the kidney homogenate. A much fainter band was observed for the lung preparation, but liver, spleen, bone marrow, and other tissues examined were negative. Northern blot analysis further revealed that the expression level of the plasma GSH-Px gene was high in kidney and low in lung. No transcript was detected in liver or spleen. These results indicate that plasma GSH-Px is predominantly synthesized and secreted by renal cells.

Amino Acid Sequence↗