Biomedical subjects

T Hanawa

Publications and source records attributed to T Hanawa.

At least 73 records · Page 4Linked to original sources

PubMed1994

Induction of Yersinia enterocolitica stress proteins by phagocytosis with macrophage.

Yersinia enterocolitica is a facultative intracellular pathogen which invades to epithelial cells and survives in phagocytes. Since the internal environment of phagocytes should be stressful conditions for the phagocytosed Yersinia, the bacteria should respond to protect themselves from otherwise lethal results. We analyzed the stress-induced proteins which possibly contribute to survival of Yersinia within the phagocytes. Y. enterocolitica was radiolabeled during the growth in macrophage-like J774-1 cells, and the bacterial proteins were analyzed by two-dimensional gel electrophoresis. At least 16 proteins were selectively induced in response to phagocytosis, and several out of 16 proteins were also induced by heat shock at 42 C or oxidative stresses in vitro. Of those, two major stress proteins were identified to be homologues of DnaK and CRPA by immunoblotting analysis. These results have indicated that Y. enterocolitica exhibits a global stress response to the hostile environment in the phagocytosed macrophage.

Animals↗

PubMed1994

Release profiles of phenytoin from new oral dosage form for the elderly.

Utilization of the solid mass containing phenytoin, sodium caseinate and microcrystalline cellulose (MCC) as a new dosage form for the elderly was studied. The solid mass was prepared by treatment of the powder mixture with high pressure steam at 115 degrees C for 10 min. The stability of phenytoin in the solid mass was confirmed by infrared spectroscopy and high performance liquid chromatography. The extent of swelling of the solid mass containing phenytoin was investigated by water absorption test and gel strength test, and the swelling property was almost independent of the presence of phenytoin. The release profile of phenytoin from the solid mass was determined under various conditions, and was found to be influenced by the extent of swelling and the swollen state. It was observed that the protein adsorption to the phenytoin crystal surface and the addition of digestive enzyme also affected the release profile. In water, the solid mass prepared from a ground mixture of phenytoin and MCC showed remarkable improvement of release profile of phenytoin.

Absorption↗

PubMed1994

Diffusion of elements in porcelain into titanium oxide.

The diffusion of elements of commercial porcelain for titanium into titanium oxide during heating was investigated. Titanium was deposited on three kinds of disk-shaped porcelains by vacuum-vaporization and the porcelains were then heated. A thin titanium oxide film was formed on the porcelains by the heating. X-ray photoelectron spectroscopy was used to characterize the surfaces of the porcelains with and without titanium oxide. Only sodium, potassium, and barium diffused into titanium oxide during heating, where they formed a complex oxide with titanium. The diffusion of these elements may be involved in the bonding of porcelain to titanium.

Barium↗

PubMed1994

Preoperative mediastinoscopic assessment of N factors and the need for mediastinal lymph node dissection in T1 lung cancer.

The significance of preoperative N factor assessment in T1 lung cancer and the need for mediastinal node dissection in T1 N0 M0 cases were investigated. The results of mediastinoscopy were evaluated in patients with T1 adenocarcinoma or squamous cell carcinoma who underwent preoperative mediastinoscopy and thoracotomy from 1971 to 1991 (n = 164). Mediastinoscopy gave true negative results in 90% of patients, false negative in 1%, and true positive in 9%. The 5-year survival was 90% for patients with T1 N0 M0 disease who underwent nonradical dissection (n = 64) and 70% for those who underwent radical dissection (n = 61), indicating that the prognosis was significantly better (p < 0.05) with nonradical dissection. Distant metastasis was a common cause of death, and no death was related to local recurrence, whether nonradical or radical dissection had been performed. The results strongly suggest that preoperative mediastinoscopy and intraoperative node sampling are sufficient for assessment of N factors in T1 lung cancer. The possible relation between immunologic functional changes associated with mediastinal lymph node dissection and the prognosis in patients without evidence of positive lymph nodes should be clarified by a prospective randomized study.

Adenocarcinoma↗

PubMed1994

[A case of solitary plasmacytoma of the chest wall].

A 58-year-old man with a solitary plasmacytoma of the chest wall is reported. He was admitted because of a painless tumor on the right lateral chest wall. The chest CT scan showed a chest wall tumor surrounding the 7th and 8th ribs without rib destruction. A transcutaneous needle biopsy of the tumor with a Sure-Cut-Needle revealed a plasmacytoma. The bone marrow biopsy findings were normal. Under a diagnosis of solitary plasmacytoma, the chest wall tumor was resected. The tumor was an extramedullary plasmacytoma. Southern blot analysis of the immunoglobulin light chain gene of the tumor cells detected a rearrangement of genes in the lambda chain, while no rearrangements of immunoglobulin genes were detected in the bone marrow specimen. Seven months later another solitary plasmacytoma was found at the left radius, and was resected. Southern blot analysis of the immunoglobulin light chain gene was useful in the differential diagnosis from systemic myeloma and in determining the monoclonality of the tumor.

Blotting, Southern↗

PubMed1994

[DNA content analysis and detection of c-myc and p53 products using flow cytometry in resected lung cancer cases].

We quantitatively analyzed the c-myc and p53 products using flow cytometry in 28 cases of resected lung cancer and one case each of chorio-carcinoma, plasmacytoma, malignant mesothelioma and sclerosing hemangioma. In the lung cancer cases, c-myc and p53 products were detected in 10 cases (35%) and 7 cases (21%), respectively. These rates are higher than the DNA abnormal expression rates of the c-myc and p53 genes (15% and 12%, respectively) in our own data. In the adenocarcinoma of lung cancer cases, c-myc and p53 products were detected in 9 cases (53%) and 5 cases (29%), respectively. Among the squamous cell carcinoma cases, there were one case (11%) of c-myc expression and one case (11%) of p53 expression. DNA content analysis of the lung cancer patients revealed 7 cases of DNA diploidy and 21 cases of DNA aneuploidy. All 10 c-myc-positive cases showed DNA aneuploidy; thus the positive rate for c-myc products in the DNA aneuploidy cases was significantly different compared with the DNA diploidy cases (p < 0.05). In the sclerosing hemangioma case, we detected both c-myc and p53 products. Sclerosing hemangioma has been thought to be a benign tumor, but it may be a malignant tumor.

Adenocarcinoma↗

PubMed1994

[Preoperative staging in T1 and T2 lung cancers by mediastinoscopy and mediastinal lymph node dissection].

Between 1975 and 1992, mediastinoscopy and thoracotomy were performed on 184 T1 and 271 T2 lung cancer cases consisting of adenocarcinoma and squamous cell carcinoma. Mediastinoscopy gave true negative findings in 90.8% of the T1 patients, true positive findings in 7.6% and false negative findings in 1.6%. The comparable rates were 76.7%, 17.0% and 6.3% in T2 patients. The 5-year survival rate was 91.3% for T1N0M0 patients (n = 64) who underwent non-radical dissection (= NRD), and 69.4% for those (n = 70) who underwent radical dissection (= RD). The rate with NRD was significantly better (p < 0.006). The 5-year survival rate was 63.2% for T2N0M0 patients (n = 62) undergoing NRD, and 49.8% for those (n = 72) undergoing RD, but the difference was not significantly. Distant metastasis was a common cause of death, whereas there were no deaths due to local recurrence in the T1N0M0 patients, whether NRD or RD was performed. These results support our opinions that preoperative mediastinoscopy and intraoperative node staging are sufficient for assessment of the N factor in T1 and T2 lung cancer, and that mediastinal node dissection should not be performed in T1N0M0 patients.

Adenocarcinoma↗

PubMed1993

Early effects of sodium iodate injection on ERG in mice.

The electroretinogram (ERG) was recorded in 15 ICR albino mice before and 2, 4 and 24 h after injection of 40 mg/kg of NaIO3 and the results were compared with the corresponding ultrastructural findings. Both a- and b-wave amplitudes decreased at 2 h after injection and increased at 4 h to the levels before injection and further increased at 24 h after injection. The b-wave threshold intensity increased by 2.1 log units at 2 h after injection. Thereafter, it decreased once at 4 h and significantly increased at 24 h by 3.4 log units. Electron microscopic examination showed swollen cytoplasmic organelles of the retinal pigment epithelial cells at 4 h after injection. It was thus demonstrated that an early effect of NaIO3 on the electrical response of the mouse retina was more conspicuous than histopathological changes.

Animals↗

PubMed1993

Compositions of surface layers formed on amalgams in air, water, and saline.

The surface layers formed on both a zinc-free and a zinc-containing dental amalgam after polishing and aging in air, water, or saline, were characterized using x-ray photoelectron spectroscopy (XPS) to determine the compositions of the surface layers which might govern the release of mercury from amalgam. The XPS data revealed that the formation of the surface layer on the zinc-containing amalgam was affected by the environment in which the amalgam was polished and aged, whereas that on the zinc-free amalgam was not affected. In addition, among the elements contained in amalgam, zinc was the most reactive with the environment, and was preferentially dissolved from amalgam into water or saline. Mercury atoms existed in the metallic state in the surface layer.

Air↗

PubMed1993

[Correlation between DNA content and amplification of oncogenes (c-myc, L-myc, c-erbB-2) and correlation with prognosis in 143 cases of resected lung cancer].

DNA content analysis using flow cytometry and amplification of c-myc, L-myc, and c-erbB-2 oncogenes in 143 cases of resected lung cancer were analyzed using the same specimen, and we examined the correlation with prognosis of DNA content and amplification of oncogenes. There were 54 DNA diploid cases (38%), 81 DNA aneuploid cases (57%) and 8 DNA multiploid cases. Analysis of oncogene amplification revealed 22 cases of c-myc, 4 cases of L-myc, and 22 cases of c-erbB-2. In curatively resected cases, the 5-year survival rate was 65% in 31 DNA diploid cases, and 36% in 40 DNA aneuploid cases. There was a statistically significant difference between the two groups (p < 0.02). However, in non-curatively resected cases, the 5-year survival rate was 11% in 23 DNA diploid cases, and 33% in 49 DNA aneuploid cases. There were no statistically significant differences among these groups. The correlation between DNA content and amplification of oncogenes was as follows. In DNA diploid cases, there were 4 cases of c-myc, and 6 cases of c-erbB-2. In DNA aneuploid cases, there were 15 cases of c-myc, 4 cases of L-myc, and 15 cases of c-erbB-2. In DNA multiploid cases, there were 3 cases of c-myc, and 1 cases of c-erbB-2. Amplification of oncogenes was seen more frequently in DNA aneuploid and multiploid cases than in DNA diploid cases. In 71 curative resected cases, the 5-year survival rate for amplified cases of c-myc (10 cases) was 0%, and that of cases with no amplification was 61% (no statistically significant difference). The 5-year survival rate for amplified cases of c-erbB-2 (10 cases) was 40%, against 52% for cases with no amplification. DNA content analysis using flow cytometry was more convenient than analysis of amplification of oncogenes, and reflects the prognosis of resected lung cancer better than oncogenes. There was no relation between DNA content and gene amplification.

DNA, Neoplasm↗

PubMed1993

[A case of malignant thymoma associated with myasthenia gravis, pure red cell aplasia and high serum level of SCC antigen].

We present a case of 43-year-old man with pure red cell aplasia appearing 8 years after thymothymectomy. He underwent an operation and postoperative radiotherapy for malignant thymoma associated with myasthenia gravis in 1983. In 1991 high serum level of SCC antigen was noted and a metastatic tumor was found in the retroperitoneal region. After removal of the tumor pure red cell aplasia developed, which responded to steroid therapy. The serum level of SCC antigen is still abnormally high.

Adult↗

PubMed1993

[A case of neurinoma combined with testicular feminization syndrome].

A 23-year-old female was admitted to our hospital because of a mediastinal tumor. She complained of primary amenorrhea, and abdominal echosonography was therefore performed, revealing the absence of a uterus. Chromosome analysis revealed a 46 XY genotype, indicating the patient to be a male, not a female. Left renal venography demonstrated residual blood vessels originating in the Mullerian ducts. Thoracotomy and laparotomy were performed, and the mediastinal tumor and bilateral testes were resected. Postoperative pathology revealed that the mediastinal tumor was a neurinoma. There was no spermatogenesis, but hyperplasia of Sertoli cells in the testes was seen. Neither the neurinoma nor the testes were malignant. Bioassay of the testes showed no androgen receptors, leading to the diagnosis of testicular feminization syndrome with the complete form of androgen insensitivity. There have been many reports of an association between testicular feminization syndrome and malignant tumors of the testes, but few reports of an association between testicular feminization syndrome and benign tumors such as neurinoma. Accordingly, the present case was considered to be unusual and worth reporting.

Adult↗

PubMed1993

[Diagnosis of mediastinal neoplasms using mediastinoscopy and CT-guided needle biopsy supported by gene analysis].

Of 140 cases of mediastinal neoplasms in our hospital, histological diagnosis was confirmed in 129 cases. We examined the methods of preoperative biopsy with those 129 cases. Biopsy had been performed in 25 cases. Mediastinoscopy was performed in seven cases, needle biopsy in eight cases, lymph node biopsy in eight cases, esophageal biopsy using a gastrofiberscope in one case, transbronchial biopsy using a bronchoscope in one case. The true positive rates of those methods were 100% for both mediastinoscopy and lymph node biopsy, and 75% for needle biopsy. Preoperative misdiagnosis occurred in two cases of needle biopsy. The postoperative histological diagnosis was malignant lymphoma in both cases. We performed gene analysis of the immunoglobulin heavy chain gene, light chain kappa and lambda genes, and the T-cell receptor beta gene by use of biopsied specimens, and we found rearrangement bands of these genes in the cases of malignant lymphoma. Therefore, we summarize that gene analysis is a reliable method if malignant lymphoma is suspected. If a needle biopsy is performed under CT guidance, the needle is sure to puncture the tumor. We concluded, therefore, that if a tumor is located in the anterior mediastinum, CT-guided needle biopsy should be performed first of all. Mediastinoscopy is a useful method if the tumor is located in the mid-mediastinum.

Biopsy, Needle↗

PubMed1992

Purification and reconstitution of mu-opioid receptors in liposome.

Opioid receptors solubilized from rat brain membranes with digitonin were partially purified with a newly prepared affinity resin, AF-Amino Toyopearl, coupled with a mu-antagonist Tyr-Pro-Tyr-Tyr at the C-terminus of the peptide. The purified materials were reconstituted with an inhibitory GTP-binding protein (Gi) in liposome. From displacement analyses, two binding states, with a high and a low affinities for the mu-agonist [D-Ala2,Me-Phe4,Gly-ol5]enkephalin, were observed in the reconstituted system with Gi, only a low-affinity state was observed in the reconstituted system without Gi. The results suggested that the purified materials contained the mu-opioid receptors and could functionally couple with Gi as observed in the cell membranes.

Amino Acid Sequence↗

PubMed1992

Cytotoxicities of oxides, phosphates and sulphides of metals.

The cytotoxicities of oxides, phosphates and sulphides, which possibly form on dental alloys, were tested using the 'agar method'. The relative magnitudes of the cytotoxicities of these compounds exhibited tendencies similar to those of the metal components in the compounds. In correlation with dental amalgams, zinc oxide was the most cytotoxic, just as with metallic zinc, while tin oxides and mercury oxides exhibited no cytotoxicity. Zinc was the most influential element in the cytotoxicity of dental amalgams. On the other hand, in correlation with Ni-Cr alloys, Co-Cr alloys, and/or stainless steels a chromium oxide and a cobalt oxide showed serious cytotoxicity, whereas the iron oxides were non-cytotoxic. Sulphides, which possibly form on silver alloys, showed cytotoxicity. Oxides and phosphates of titanium and aluminium, and hydroxyapatite, were not cytotoxic, supporting the use of these materials for implants. Not only the valence of an element but also the chemical species combining with the element affect the cytotoxicity of the alloy containing it.

Biocompatible Materials↗

PubMed1992

Effectiveness of oxide films in reducing mercury release from amalgams.

The release of mercury from four freshly-triturated amalgams into air, argon, and moist air environments was quantitated at three different temperatures. Although a measurable amount of mercury was released from dental amalgam, the evaporation rate was immediately reduced by several phenomena, the most important being the formation of an oxide film on the surface. This hypothesis was supported by the fact that release rates were elevated in an inert argon environment, but declined dramatically once air was introduced and oxidation could occur. The further amalgamation of "free" mercury, as well as the presence of water vapor, also contributed to the reduced release rates observed during aging. Mercury release was reduced to a negligible level within three to four hours after trituration. Only one of the amalgams, Tytin, demonstrated a thermal dependence for mercury release in air. The results of this study suggest that the exposure to mercury vapor from a freshly placed amalgam restoration would be negligible in consideration of the normal estimated daily intake from all other sources.

Air↗

PubMed1992

Transient increase of b-wave in the mouse retina after sodium iodate injection.

Twenty C57 black mice received an injection of 40 mg/kg of sodium iodate through the caudal vein. The electroretinograms (ERGs) were recorded before and after injection. Flash stimuli with the maximum illuminance, 30,000 lux, were given at increasing levels of illuminance in 0.6 log U steps for 13 levels of intensity. The a- and b-wave amplitudes increased linearly with increased stimulus intensity for approximately 5.0 log U before being saturated. Twenty four hours after injection, the intensity-amplitude curve shifted toward the higher intensity region. It was calculated that the sensitivity loss of the b-wave after injection was 2.0 log U, although the maximum amplitude was larger and the peak latency was delayed. The same results were seen less obviously in the ERGs 48 hr after injection. After 96 hr, both waves were greatly attenuated and even abolished. At the time the increased ERGs were recorded, the histopathologic findings exhibited severe damage of the retina in the pigment epithelium and in the outer layer.

Animals↗

PubMed1992

[Diagnosis, incidence, clinicopathology and surgical treatment of acquired tracheobronchomalacia].

We report our recent findings on the diagnosis, incidence, appearance of the trachea at autopsy, and surgical treatment of acquired trachobronchomalacia. In the diagnosis of this disease, continuous dynamic CT scanning (1 slice/0.6 second) from inspiration to deep expiration was better than X-ray cine recording. It is difficult to observe the most collapsed airway on coughing using bronchofiberscopic recording, because its duration time was estimated to be 1/10 second by X-ray cine recording, whereas the findings at one instant were easily recorded by video-bronchoscopy on coughing. The degree of severity of this disease was classified into three groups. 1st degree 0-50% narrowing of airway caliber, 2nd degree 50-75%; and 3rd degree 75-100%. Severity of 2nd or 3rd degree was present in 542 (12.7%) of 4283 patients suffering from chest disease who underwent bronchoscopy. Seventy-two percent of patients were aged 50 to 80 years. Third degree tracheomalacia was found in 131 patients with an incidence of 3.1%, which increased from 2.2% at 50 years to 6.2% at 80 years. The autopsy findings of the trachea consisted of fragmentation of the tracheal cartilage and extension of the membranous portion. The pathogenesis may be varied with different types of collapse of the airway, including the saber sheath type and the crescent type. Surgical treatment consists of prevention of the airway collapse by wrapping the airway with Marlex mesh and bonding Lyodura (lyophilized dura mata) with fibrin glue, which is more reliable than the span plasty proposed by Nissen.

Adolescent↗