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Biomedical subjects

Y Hosaka

Publications and source records attributed to Y Hosaka.

At least 73 records · Page 4Linked to original sources

Combined analysis with Bcl-2 and P53 immunostaining predicts poorer prognosis in prostatic carcinoma.

PURPOSE: The objective of the current study is to investigate the relationship between bcl-2 and p53 expression and prognosis in prostatic carcinoma. MATERIALS AND METHODS: One hundred and forty-six needle core biopsy specimens obtained before any treatment were used for immunohistochemical detection of bcl-2 and p53 positivity. The relationship between these proteins was assessed by serial sections. Associations with Gleason score, clinical stage and patient survival were studied. Additionally, multivariate analysis by Cox proportional hazard model was used to determine the prognostic significance of these proteins. RESULTS: Bcl-2 positivity was found in 20% and p53 in 27% of 146 prostatic carcinomas. Both bcl-2 and p53 positivity were found only in 5%. They were expressed almost reciprocally in the tumors. P53 positivity correlated with high Gleason grade tumors. Bcl-2 positivity correlated with high T stage. Both bcl-2 and p53 positivity correlated with poor survival and short progression-free period. Multivariate analysis revealed that bcl-2 positivity was an independent prognostic indicator (p = 0.001). CONCLUSIONS: Bcl-2 and p53 were almost independently expressed in prostatic cancer. Both correlated with malignant phenotypes of prostatic cancer. The combined data from this staining further improved the ability to predict the patient prognosis.

Disease Progression↗

A case of congenital ectopic nails on bilateral little fingers.

Congenital ectopic nails are a rare anomaly, but we observed a case of a 43-year-old woman with ectopic nails at the tips of her bilateral little fingers. On X-ray, the distal phalanx of the each little finger appeared depressed. We surgically removed the ectopic nails. One year and 6 months later, no relapse had occurred. The histopathological examination revealed undifferentiated nail tissue including nail, nail matrix, and nail epithelium.

Adult↗

[A case of hormone-refractory prostate cancer responsive to low-dose prednisolone therapy].

A 67-year-old man with hormone-refractory (stage D2) prostate cancer was admitted to the hospital because of general malaise and bone pain. The patient had been receiving hormonal therapy, which was discontinued after admission. Instead, 10 mg per day of prednisolone was administered orally. His symptoms improved, and the serum prostate specific antigen (PSA) level decreased markedly. After 18 weeks of treatment with prednisolone, the serum PSA level rose again, and bone pain worsened. The patient died of cancer one month later.

Aged↗

Detection of influenza virus RNA in peripheral blood mononuclear cells of influenza patients.

Gastroenteritis, arthralgaia and myalgia are frequently associated with influenza virus infections in humans. One explantation for these symptoms may be extrarespiratory transmission of virus by peripheral blood mononuclear cells (PBMC). We tried to detect genomic viral RNA of the nucleoprotein (NP) and H3 subtype hemagglutinin (HA) genes by the method of RT-PCR in PBMC of 18 children aged 1-14 who suffered from an influenza outbreak in the Kansai district of Japan between December 1992 and February 1993. Three of the 18 samples were RT-PCR positive. The NP gene sequence observed in one patient's PBMC was identical to that obtained from his throat swab fluid. The HA gene sequences observed in the two other PBMC differed from those of RT-PCR-amplified DNA from throat swabs by an order of 3-9 nucleotides. We believe these results suggest the presence of a PBMC-associated virus.

Adolescent↗

Human urinary soluble thrombomodulin (MR-33) improves disseminated intravascular coagulation without affecting bleeding time in rats: comparison with low molecular weight heparin.

We compared the antithrombotic and hemorrhagic effects of naturally existing human urinary soluble thrombomodulin (MR-33) with those of low molecular weight heparin (LMW-heparin) in rats. In in vitro experiments, MR-33 prolonged APTT in a dose-dependent fashion; its effect in this respect was as potent as that of LMW-heparin, but it was less potent than unfractionated heparin (UF-heparin). MR-33 was effective on endotoxin- or thromboplastin-induced disseminated intravascular coagulation (DIC) in rats. In both DIC models, infusion of MR-33 improved hematological abnormalities compatible with DIC in a dose-dependent, fashion without excessive prolongation effect on APTT. Although LMW-heparin and UF-heparin also improved both DIC models, excessive prolongation of APTT was observed at high doses. It is well-known that the excessive prolongation of APTT with antithrombotic drugs like heparins is an index for hemorrhage, which is a major side effect in the treatment of DIC. We therefore further compared the antithrombotic (Benefit: dose required for 50% inhibition of fibrinogen decrease: ED50) and hemorrhagic (Risk: minimum dose required for significant prolongation of bleeding time) effects of MR-33 and LMW-heparin in the thromboplastin-induced DIC model. As a result, Benefit-Risk ratio was 1:27 for MR-33 and 1:3 for LMW-heparin. These results indicate that MR-33 may be a clinically useful antithrombotic agent with reduced risk for hemorrhage compared with LMW-heparin.

Animals↗

[Structure and function of influenza virus nucleoprotein (NP)].

Influenza virus nucleoprotein (NP) is the major structural protein which interacts with the 8 segment RNAs, to make the panhandle structure of RNPs, nucleocapsids, together with 3 polymerase protein complex (PB2, PB1, and PA). The NP proteins (498 aminoacids, MW 56,000) self-polymerize to form the panhandle structure similarly as the nucleocapsids. The nucleocapsids ensure the base pairing RNA structure in the handle region corresponding to the complementary structure in the both ends of vRNAs. This handle structure is supposed to play roles in regulation of switch for transcription and replication, and encapsidation. The NP protein is one of the type-specific antigens distinguishing among influenza A, B, and C type, and a target of cross-reactive CTL.

Nucleocapsid↗

[Antigenic epitopes of influenza virus specific CTL].

CTLs play an essential role in the protection to influenza virus infection. Virus specific CTLs recognize the complex of class I molecule and epitope peptide derived from viral proteins on surfaces of virus infected cells. In these 10 years great progress has been made in understanding of the process of epitope peptide production and the structure of the peptide. It has been clearly shown that proteasome and TAP are involved in the class I restricted antigen processing and epitope peptides have motifs depending on class I allele. In this article topics concerning CTL epitopes of influenza viruses are described; especially prediction and identification of epitopes are mainly discussed.

Epitopes↗

[Viremia in influenza: detection by polymerase chain reaction].

Gastroenteritis, arthralgia and myalgia are frequently associated with influenza virus infections in humans. One explanation for these symptoms may be that they are due to extra respiratory transmission of virus by viremia. We tried to detect genomic viral RNA of the nucleoprotein (NP) and H3 subtype hemagglutinin (HA) genes by method of RT-PCR in peripheral blood mononuclear cells (PBMC) of 18 children aged 1-14 who suffered from an influenza outbreak in the Kansai district of Japan between December 1992 and February 1993. Three of the 18 samples were RT-PCR positive. The NP gene sequence observed in one patient's PBMC was identical to that obtained from his throat swab fluid. The HA gene sequences observed in the two other PBMC differed from those of RT-PCR amplified DNA from throat swabs by an order of 3-9 nucleotides. Moreover we tried to isolate virus by co-culture with MDCK cells and RBC or WBC of the patients from an influenza outbreak between December 1993 and March 1994. No virus was isolated from 9 patients suffering from H3 subtype but virus was isolated from 5 of 17 patients suffering from type B influenza virus. We believe these results suggest that the viremia on influenza infection is not so rare.

Adolescent↗

Responses of peri-implant tissues to undisturbed plaque formation in dogs: clinical, radiographic, and microbiological findings.

The present investigation evaluated the clinical and microbiological effects of long-term undisturbed plaque formation on peri-implant tissues. Four mongrel dogs were used in the study. The mandibular 3rd and 4th premolars were extracted. Three months later, four Brånemark implants (BR, n = 8) or Integral implants (IN, n = 8) were placed in the edentulous area of each dog. After another 3 months, an abutment connection was performed. Plaque control regiment was maintained for 30 days until the superstructure was placed (Day 0: baseline). Then the plaque control program was terminated to allow gross plaque accumulation. Clinical, radiographical and microbiological data were recorded at the baseline, and at 90 and 180 days after the termination of the plaque control. Values for the clinical indices such as probing depth, plaque index and bleeding on probing increased at day 90 on both the implant and tooth sites, and remained unchanged at day 180. Significantly more implant sites showed bleeding on probing than did tooth sites. Neither implants nor tooth sites showed clinically significant changes in mobility. No distinct bone resorption was observed over time by radiography. In microscopic morphological observations, cocci dominated at the baseline, and decreased by day 180, while the proportion of motile bacteria increased. In a culture study, black-pigmented anaerobic rods, which consisted predominantly of Porphyromonas gingivalis-like bacteria, were consistently found from the baseline to day 180. No Actinobacillus actinomycetemcomitans-like organisms were isolated. These results indicate that, although the long-term plaque accumulation did not cause marked periodontal destruction, the peri-implant tissue may be more susceptible to plaque accumulation than the periodontal tissue, and that teeth may serve as a reservoir for the bacterial colonization of the implant sulcus.

Alveolar Bone Loss↗

bl-2 [corrected] Expression on prostate cancer and its relationship to cell cycle and prognosis.

BACKGROUND: bcl-2 protein is an oncoprotein encoded by a protooncogene bcl-2 which is thought to be a key gene for the regulation of cell life and death. bcl-2 protein has been reported to be expressed in a subset of prostate cancers, and its biological role in this disease has not yet been elucidated. This present study focused on the cell cycle analysis of bcl-2 immunoreactivity in prostate tumor samples and correlated findings with the prognosis of the patients. METHODS: Archival tissues from 37 prostate cancers were submitted for immunohistochemistry and DNA analysis via flow cytometry. All tissues were obtained before the patients received any treatment. Immunohistochemistry was performed using streptavidin biotin procedures, and DNA flow cytometry was done by a combination of two methods. RESULTS: Fourteen of 37 prostate cancers (38%) exhibited bcl-2 immunoreactivity. bcl-2 positive prostate cancers significantly correlated with DNA aneuploidy and higher proliferation indices, but not with histological differentiation. Clinically, there was a poorer prognosis for patients with bcl-2 positive prostate cancer. CONCLUSIONS: Our data indicates that bcl-2 protein expression in prostate cancer is associated with cell proliferation and may serve as a predictive factor for the prognosis of prostate cancer.

Adenocarcinoma↗

Nuclear deoxyribonucleic acid ploidy of testicular tumors: peculiar features and clinical significance.

To verify the usefulness of testicular DNA ploidy measurement, we tried some approaches to tumorous and nontumorous testes. Separation of paraffin-embedded specimens into single dissociated nuclei was performed by Hedley's technique and nuclei were stained with propidium iodide. Control nontumorous testes were clearly separated into the three-peak type with a high G2M percentage and the two-peak type with a low G2M percentage. Among testicular tumors, 25% (8 of 32) had a normal DNA diploid pattern, 15.6% (5 of 32) had an increased DNA tetraploid pattern including DNA polyploidy, and 59.4% (19 of 32) were DNA aneuploid. In detail, 26.3% (5 of 19) of seminomas and 23.1% (3 of 13) of nonseminomas were DNA diploid. Interestingly, seminomas showed a variety of DNA histogram profiles. Among DNA aneuploid tumors, the DNA index of a seminoma was significantly higher than that of a nonseminoma. Among patients who received curative orchiectomy, postoperative metastases did not occur in any of the 8 DNA diploid or 5 tetraploid tumors, but did occur in 4 (21.1%) of 19 DNA aneuploid tumors during an at least 6-year follow-up. Clinicopathological findings were not as predictable as DNA ploidy. Flow cytometry appeared to be useful to characterize testicular tumors.

Adolescent↗

Identification of Kk-restricted T-cell epitope within influenza virus nucleoprotein.

In order to determine the epitope structure in peptide NP50-63, which has been reported to be the only Kk-restricted T-cell antigen within the influenza virus (A/PR/8/34) nucleoprotein, a series of 13 peptides truncated from C- and N-termini of NP50-63 were synthesized and their sensitizing activities against Kk-restricted nucleoprotein-specific cytotoxic T lymphocytes (CTLs) were examined. One of the 13 peptides, NP50-57, sensitized L929 cells at the nM level, which was 100-1000 times lower in concentration than that at which the other peptides sensitized these cells. The presence of NP50-57 in A/PR/8/34-infected L929 cells was also investigated. Acid extracts of virus-infected cells were separated on a reverse-phase HPLC column and then anion-exchange column. By both separations, only one peak of sensitizing activity against nucleoprotein-specific CTLs was observed. The position of the peak coincided with that of the elution of NP50-57. These results strongly suggest that NP50-57 is the natural epitope in the antigenic structure, NP50-63.

Amino Acid Sequence↗

Treatment of nevus Ota by liquid nitrogen cryotherapy.

Nevus Ota is a disfiguring facial dermal melanosis that is observed rarely in Caucasians but is common in Asians. Until recently, carbon dioxide snow cryotherapy had been used most frequently to treat this disorder, but the results were not always satisfactory and often left scarring after treatment. During the past 15 years, we have treated a total of 600 cases of dermal pigmentary facial disfiguration using CRYO-MINI, a liquid nitrogen cryogenic instrument with a removable disk-shaped copper tip. We have found this method to be simple and extremely effective in the treatment of nevus Ota and senile lentigines, and it is also useful for treatment of delayed nevus spilus and blue nevus. This report presents our techniques and experiences as well as the results achieved with four patients who have a deeply situated type of nevus Ota. Associated problems to be considered in future treatment are discussed also.

Adult↗

[Evaluation of reliability of IPSS by 24-hour uroflowmetry].

BACKGROUND: Although the international prostate symptom score (IPSS) is now often used to assess the symptoms of BPH, whether or not patients answer the questions correctly has not been validated objectively. METHODS: Reliability of IPSS was evaluated by 24-hour uroflowmetry in 20 hospitalized male patients. Six of them had prostatic hypertrophy or cancer, and the evaluation was performed before and after TURP or hormonal therapy in these six patients. The objective scores for frequency and nocturia were obtained from the time recorded on IC card. The objective score for intermittency was calculated from the uroflow curves. RESULTS: The answer about frequency was not correct compared with the objective scores for frequency. The answers about nocturia and intermittency were almost the same as the corresponding objective scores. The answer for weak stream correlated with the average of peak flow rate. However, the threshold of peak flow rate for "weak stream" fluctuated markedly before and after the treatment in the same individuals. The answer for hesitancy had no correlation with the hesitation time. Patients seemed to understand the question translated in Japanese as "have you need force to urinate?" CONCLUSION: Before wider use of IPSS in Japan, the correct translation of the questions and verification of the usefulness of the questions in large number of Japanese patients seem necessary.

Humans↗

Soluble thrombomodulin purified from human urine exhibits a potent anticoagulant effect in vitro and in vivo.

We examined the anticoagulant activity of two major molecules of soluble thrombomodulin purified from human urine. The apparent molecular weights of these urinary thrombomodulins (UTMs) were 72,000 and 79,000, respectively. Both UTMs showed more potent cofactor activity for protein C activation [specific activity > 5,000 thrombomodulin units (TMU)/mg] than human placental thrombomodulin (2,180 TMU/mg) and rabbit lung thrombomodulin (1,980 TMU/mg). The UTMs prolonged thrombin-induced fibrinogen clotting time (> 1 TMU /ml), APTT (> 5 TMU/ml), TT (> 5 TMU/ml) and PT (> 40 TMU/ ml) in a dose-dependent fashion. These effects appeared in the concentration range of soluble thrombomodulins present in human plasma and urine. In the rat DIC model induced by thromboplastin, administration of UTMs by infusion (300-3,000 TMU/kg) restored the hematological abnormalities derived from DIC in a dose-dependent fashion. These results demonstrate that UTMs exhibit potent anticoagulant and antithrombotic activities, and could play a physiologically important role in microcirculation.

Adult↗