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Biomedical subjects

Y Hosaka

Publications and source records attributed to Y Hosaka.

At least 91 records · Page 5Linked to original sources
PubMed1995

Characterization of defectiveness in endogenous antigen presentation of novel murine cells established from methylcholanthrene-induced fibrosarcomas.

Three cell lines (4A1, 4C2 and 6D1 cells) derived from fibrosarcoma induced by the inoculation of 3-methylcholanthrene into C3H/HeN (H-2k) mice were examined for their ability to present antigens to CD8+ cytotoxic T lymphocytes (CTL). 6D1 and 4C2 cells were deficient in presenting endogenously synthesized influenza virus antigens to CTL, but they were able to present antigens when they were sensitized with a synthetic epitope peptide. The expression of the H-2 Kk gene in 4C2 and 6D1 cells was much reduced and was detectable only with Northern blot hybridization. The expression of two transporter genes (TAP1 and TAP2), examined by Northern hybridization, was also reduced in both cells, and negligible particularly in 4C2 cells. Interferon-gamma (IFN-gamma) treatment of these cells induced expression of Kk, TAP1 and TAP2 genes and rescued the defect of class I-restricted antigen presentation in 4C2 and 6D1 cells. Even after this treatment, however, antigen-presentation capability of 4C2 cells was still much lower than that of normal 4A1 cells. This finding suggests that 4C2 cells might have an additional defective gene(s), whose products are involved in the processing of class I-restricted antigen, besides the Kk and TAP genes, and this may explain the difficulty of 4C2 cells to induce tumour-specific immunity, as described previously. To our knowledge, the 4C2 cell is the first tumour cell postulated to have more than three defective genes involved in class I-restricted antigen presentation.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

Poisoning by the red alga 'ogonori' (Gracilaria verrucosa) on the Nojima Coast, Yokohama, Kanagawa Prefecture, Japan.

A food poisoning case due to the ingestion of 'ogonori', an edible red alga, occurred at Yokohama, Kanagawa Prefecture, Japan, in late October 1993, resulting in two victims, including one death (female). No causative agent present in the ogonori was found from a routine bioassay for marine toxins. From the production of increased amounts of prostaglandins (PGs), mainly PGE2, by the alga on stimulation by cutting or soaking in fresh water, and further increase of PGE2 by addition of arachidonic acid, it appeared that an enzyme, probably fatty acid cyclooxygenase, in the ogonori and the body of the victim, was acting on the highly unsaturated fatty acids in the oil of the ingested seafood and in the blood hemorrhaged from the stomach of the victim. This resulted in the production of over 30 mg of PGE2 and small amounts of other PGs in a comparatively short time. With this dosage the victim suffered from nausea, vomiting, and hypotension, and died of hypotensive shock. PGE2 seems to work more selectively on females. This type of poisoning is very unusual, and differs from the more familiar forms of poisoning occurring after ingestion of marine organisms.

Animals↗
PubMed1994

The effect of prostaglandin E1.alpha CD on vibratory threshold determined with the SMV-5 vibrometer in patients with diabetic neuropathy.

We studied the effect of prostaglandin E1.alpha CD (PGE1) on diabetic peripheral neuropathy by evaluating subjective symptoms and vibration sensation using a new vibrometer (SMV-5). Patients with diabetic neuropathy (n = 38) were divided into three groups; group A received no drugs (control), group B was treated with 1500 micrograms/day of oral methyl vitamin B12 (VB12) for four weeks, and group C received 1.2 micrograms/kg/day PGE1 intravenously for four weeks. There was a close relationship between symptom scores and vibratory threshold (VT). The effect of PGE1 on subjective symptoms and VT were compared with those in groups A and B. Patients who received PGE1 showed a significant improvement rate in pain and hypesthesia compared to patients in groups A and B, and in numbness compared to group A. During the study period, there was no significant change in VT in groups A and B, whereas VT was significantly improved at styloid process (P < 0.05) and at medial malleolus (P < 0.001) in group C. Our results confirmed that PGE1 significantly improved both subjective symptoms and VT, indicating that PGE1 therapy may be useful in diabetic neuropathy.

Administration, Oral↗
PubMed1994

Locally delivered minocycline and guided tissue regeneration to treat post-juvenile periodontitis. A case report.

A case of post-juvenile periodontitis in a 28-year-old female patient is described along with new periodontal treatment modalities. Administration of minocycline-HCl with local drug delivery system was introduced as a part of initial periodontal therapy following microbiological and immunological examinations. The lesions were subsequently treated by guided tissue regeneration, which resulted in considerable gain of attachment with minimal recession of marginal gingiva. This observation suggests that the local delivery of antibiotics and regenerative therapy may prove to be effective alternative modalities in treatment of post-juvenile periodontitis.

Administration, Topical↗
PubMed1994

[Two-color flow cytometric analysis of lymphocytic subsets in renal cell carcinoma].

The subsets of tumor infiltrating lymphocytes (TILs) in 17 patients with renal cell carcinoma were studied by two-color flow cytometry and immunohistochemistry. In grade 1 tumors, CD4-positive cells were significantly increased compared to grade 2 and 3 tumors (35 +/- 7% vs 25 +/- 10%) (p < 0.05). In 10 of 14 patients, CD8-positive cells were predominant over CD4-positive cells, resulting in less than one in CD4/CD8-ratio. Regarding CD4 cells in all 17 cases, the helper T-cells (CD4-positive and CD45RA-negative) were statistically predominant over the inducer T-cells (CD4-positive and CD45RA-positive) (p < 0.01). When CD8 cells were investigated in 16 out of the 17 cases, the cytotoxic T-cells (CD8-positive and CD11b-negative) were found also significantly predominant over the suppressor T-cells (CD8-positive and CD11b-positive) (p < 0.01). Immunohistochemically, the infiltrating pattern of TILs in the 17 patients was classified into cluster (N = 4), separate (N = 6), and mixed types (N = 7). The tumor in the cluster and mixed type had a tendency to be dominant in low grade tumors, and had the prominent CD8-positive cells (more than 90% were cytotoxic T-cells) over CD4-positive cells. However, no statistical significance was noted in this finding. The advanced tumor tended to show the single type of TIL infiltration. These results suggest that cytotoxic T-cells consisted of most of TILs in cluster and mixed types play an immunoreactive role against renal cell carcinoma.

Adult↗
PubMed1994

Clinical and flow cytometric analyses of renal cell carcinomas with reference to incidental or non-incidental detection.

In recent years renal cell carcinomas have been diagnosed as incidental findings. The tumors are usually associated with low stage and good prognosis. To find out if they might have a different malignant potential from suspected tumors, we retrospectively compared 56 cases of incidentally detected tumors with 84 cases of suspected tumors, with regard to tumor stage, nuclear grade, tumor size and DNA ploidy pattern as evaluated by flow cytometry. The incidentally detected tumors were lower in stage (P < 0.01), smaller in size (P < 0.01) and higher in probability of survival (P < 0.02) than the suspected tumors, as other studies have reported. Meanwhile, there was no difference in nuclear grade, DNA ploidy pattern and survival in stage I tumors between the two groups of renal cancers. The results suggest that the better prognosis in incidental renal cancer might be due to early detection rather than lower malignant potential of this specific type of renal cancer.

Adult↗
PubMed1994

Effect of initial therapy on dynamics of immunogloblin G levels to some periodontopathic bacteria in serum and gingival crevicular fluid.

Using enzyme-linked immunosorbent assay, the IgG antibody levels to specific gram-negative periodontopathic bacteria in serum of 21 adult periodontitis patients and the gingival crevicular fluid (GCF) from 42 sites with destructive lesions and 21 healthy sites were evaluated before and after initial preparation. Porphyromonas gingivalis, Bacteroides forsythus, Prevotella intermedia, Prevotella nigrescens, Campylobacter rectus, Treponema denticola and Actinobacillus actinomycetemcomitans in subgingival plaque samples from the patients were examined by indirect immunofluorescence microscopy. Subgingival plaque, GCF, and serum samples were taken at baseline and three weeks after initial preparation. For 14 patients, changes in clinical parameters due to the initial preparation were correlated with reduction of periodontopathogens and to IgG antibody levels in GCF and serum against them. P. gingivalis, T. denticola and C. rectus were found to be predominant in destructive sites. No significant differences were found in GCF IgG antibody levels between destructive and healthy sites. In destructive sites, the prevalence of P. gingivalis and C. rectus was significantly correlated with elevated IgG antibody against these microorganisms in GCF. The initial preparation resulted in significant reduction of serum IgG antibody levels against all microorganisms tested. No decrease in GCF IgG antibody was observed, but levels to P. gingivalis and C. rectus were significantly increased (p<0.05). The assessment of GCF IgG antibodies to specific periodontopathic bacteria may be of considerable value in reflecting the conditions of periodontitis.

Adult↗
PubMed1993

Aesthetic camouflage of bilateral cleft lip scars: technical revisions.

We have attempted to change the two scar lines of bilateral cleft lip repair into one zigzag scar line. The prolabium is used to push up the columella and the nasal tip. The donor site of the prolabium is closed by transposition of the nasolabial flap. The postoperative scar shows one zigzag line at the center of the lip. This method has many advantages including an inconspicuous scar, repair of the short columella and flat nasal tip, repair of a wide nose, and repair of the whistling deformity. Complications of this method are maxillary retardation, long lip deformity, and keloid formation. However, these can be avoided by modifying the method.

Adolescent↗
PubMed1993

Successful gonadotrophin treatment of hypogonadism in postoperative patients with macroprolactinoma and persistent hyperprolactinaemia.

We report on two males with prolactinoma in whom hyperprolactinaemia and hypogonadism persisted for several years postoperatively despite the administration of a dopamine agonist or bromocriptine. In these patients, a GnRH test revealed no response in the levels of serum LH or FSH. An hCG stimulation test provoked no response in the serum levels of testosterone. Case 1, who was 28 years old at the first visit, received parenteral testosterone and appreciable virilization of the genitalia was noted within a few months. When he married and desired to father a child, the treatment was switched to hCG/hMG combined therapy and spermatozoa appeared subsequently in the ejaculate, although their numbers were low. His wife conceived and delivered a healthy baby girl. Case 2 was a single young man who presented with hypogonadotrophic hypogonadism and hyperprolactinaemia. He was started on hCG injections three times per week and the maturation of his genitalia was advanced rapidly. Semen analyses showed sperm concentration and motility to be within the normal range. Post-treatment GnRH test revealed no improvement in gonadotrophin responses for LH or FSH. In both cases, the hCG test repeated after the gonadotrophin treatment showed normal basal and stimulated testosterone levels. During the course of gonadotrophin treatment in these cases, serum prolactin levels remained elevated, and it is suggested that, in the two cases, the hypothalamo-pituitary function was disturbed by the tumour or its manipulation and the capacity of the pituitary gland to secrete gonadotrophin was impaired. Under such circumstances with persisting hyperprolactinaemia, hCG and/or hCG/hMG combination treatment can induce normal virilization and advance spermatogenesis sufficiently to achieve fertility.

Adult↗
PubMed1993

Significance of serum antibody against surface antigens of Actinobacillus actinomycetemcomitans in patients with adult periodontitis.

This study was undertaken to examine the prevalence of Actinobacillus actinomycetemcomitans, its serotype distribution and the serum immune responses against its surface antigens in 41 Japanese patients with adult periodontitis. The dominant A. actinomycetemcomitans serotype isolated was serotype c. Immunoblot analysis of 3 serotypes of A. actinomycetemcomitans-sonicated antigens and the patient sera revealed that the reactivities with serotype c were the most frequent and that heat-stable surface serotype-specific antigen appeared to be immunodominant. Elevated serum immunoglobulin G titers to extracted lipopolysaccharide and fimbriae antigen of A. actinomycetemcomitans were noted for the patient sera by enzyme-linked immunosorbent assay. High serum immunoglobulin G titers to the fimbriae antigen detected in patients without cultivable A. actinomycetemcomitans suggested the possibility that the elicited antibody to the antigen played a role in eliminating A. actinomycetemcomitans from the periodontal lesions.

Adult↗
PubMed1993

Relative avidity of serum immunoglobulin G antibody for the fimbria antigen of Actinobacillus actinomycetemcomitans in patients with adult periodontitis.

The relative avidity of serum immunoglobulin G antibody for the fimbria antigen of Actinobacillus actinomycetemcomitans was assessed by diethylamine dissociation enzyme-linked immunosorbent assay in patients with adult periodontitis. High-titer sera from patients not harboring A. actinomycetemcomitans had significantly higher avidities for the fimbria antigen than did high-titer sera from patients with A. actinomycetemcomitans in their periodontal pockets. The elicited antibodies against the fimbria antigen may afford protection against A. actinomycetemcomitans infection.

Actinobacillus Infections↗
PubMed1993

Individual difference in toxic diffuse goiters assessed by heme-based specific activity and Km value.

Thyroid peroxidase (TPO) was purified from each thyroid of 10 patients (experiment 1) and 4 patients (experiment 2) with toxic diffuse goiter by a simplified method with monoclonal anti-TPO antibody-assisted immunoaffinity column chromatography. The final preparations were used to measure the heme concentration based on the cyanide difference spectrum, and to determine the Km and kcat values from double reciprocal plots in the assay employing guaiacol and iodide as the second substrates. The heme-based specific activities of TPO purified from thyroids in experiment 1 were higher than those in experiment 2, which were probably impaired by freezing-thawing, and those of porcine TPO previously reported. There were some differences in the kinetic properties between experiment 1 and experiment 2, but the individual differences within each group were relatively small, the values for CV (= SD/mean) being 0.16-0.48.

Adolescent↗
PubMed1993

Acute subdural hematoma: severity of injury, surgical intervention, and mortality.

Sixty patients with acute subdural hematoma were treated at Tokyo Metropolitan Hiroo Hospital between 1981 and 1989. The overall mortality was 55% and the functional recovery rate 30%. Thirteen (93%) of 14 patients with a Glasgow Coma Scale (GCS) score of 3 died, while all eight patients with a GCS score of 7 or more achieved functional recovery. The mortality of patients with GCS scores of 4-6 ranged from 45 to 67%. Patients with GCS scores of 4-6 over 65 years old had a mortality of 82%, compared to 50% mortality for those aged 19-40 years. The mortality for patients with GCS scores of 4-6 operated on within 4 hours of injury was 62% in contrast to 33% for those operated on from 4 to 10 hours. Patients with GCS scores of 4-6 who underwent craniotomy with evacuation of the hematoma achieved significantly better recovery than those treated by burr holes. Four patients with GCS scores of 4-6 died in spite of decompressive craniectomy or craniotomy with duroplasty. The mortality is only influenced by age and type of surgical intervention among patients with GCS scores of 4-6. Shorter time from injury to surgical evacuation does not affect mortality within 10 hours of injury.

Adolescent↗
PubMed1993

Immortalization of rabbit corneal epithelial cells by a recombinant SV40-adenovirus vector.

PURPOSE: Cultured corneal epithelial cell is detrimental because of its short life span and its heterogeneity. We have tried to establish an immortalized epithelial cell line. METHODS: Primary cultured rabbit corneal epithelial cells were infected with a recombinant SV40-adenovirus vector and were cloned three times. RESULTS: The immortalized cell continued to grow by more than 400 generations through 100 passages. SV40-associated large T antigen was demonstrable on the nuclear membrane of these immortalized cells by immunofluorescence technique. This cell line exhibited a similar cobblestone-like appearance as normal corneal epithelial cells. Transmission electron microscopy showed a line of evidence for stratification, including desmosome formation and microvilli development at the superficial cell layer. As the culture grew, these cells began to express cornea-specific 64 kD cytokeratins. In contrast to cultured normal corneal epithelial cells, this cell line had a good proliferative ability after a long-term storage in liquid nitrogen. CONCLUSIONS: Because this particular cell line shares properties consistent with normal corneal epithelial cells and is easy to handle in vitro, it may serve as a useful tool in corneal epithelial research.

Animals↗
PubMed1993

Immunoelectron microscopy of parainfluenza virion glycoproteins with polyclonal and monoclonal antibodies: movement of glycoprotein with monoclonal antibody.

Two glycoproteins (HN and F) of parainfluenza virus were immunogold-labeled with polyclonal and monoclonal antibodies, respectively, and their labeling patterns were compared. Both glycoproteins HN and F were efficiently and homogeneously labeled with polyclonal antibodies, whereas they were labeled much less and heterogeneously with monoclonal antibodies. When either protein was initially labeled with monoclonal antibody, and then the other one, with polyclonal antibody, immunolabels of two glycoproteins were almost completely segregated. Although this segregation deformed virion morphology, it supported the concept of monoclonal antibody-mediated movements of glycoproteins.

Animals↗
PubMed1993

Electron microscopy of influenza virus growth in a human lymphoblastic leukemia cell line, MOLT4 cells.

We studied the interaction of influenza virus and a human lymphoblastic line, MOLT4 cells, as a model for that of influenza virus and human T lymphocytes. Influenza virus was found to grow relatively poorly in MOLT4 cells in terms of yield of plaque forming units (PFU) in the presence of trypsin. However, electron microscopy of infected cells revealed that a lot of viral antigens were accumulated in the cytoplasm as well as in the nucleus, and a number of budding virions were on the cell surfaces. Consistently, gel electrophoresis of infected cells demonstrated that the synthesis of virus proteins was abundant. These findings indicated that MOLT4 cells were permissive to influenza virus growth, with production of a relatively smaller number of infectious particles in terms of PFU. Production of interferon (IFN)-alpha and -gamma were not detected in this system by ELISA.

Animals↗