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Biomedical subjects

M Shiba

Publications and source records attributed to M Shiba.

At least 91 records · Page 5Linked to original sources
PubMed1989

[Some observations of the interface of metal bonding porcelain by the electron probe surface shape analyzer].

The metal bonding porcelain has been widely used for having the excellent qualities of color tone, corrosive resistance, abrasion proof and so on as the dental restorative material. And the many studies on its bonding mechanism have been done. However, there still remains some problems in operation of technical work. The Problems are how to choose polishing instruments for finishing cast metal before filled porcelain, and how to thin the part of dental neck as much as possible so that cast metal is not transmitted. So, as a clue to elucidate these problems, the appearance of metal/porcelain interface has been investigated by using the Electron Probe Surface Shape (EPSS) Analyzer. In this paper, two precious metals (KIK and HARD 2 on the market) and one nonprecious metal (TALLADIUM on the market) were used as base metal, and porcelain powder of two kinds, which were come onto the larket as VITA and DUCELAM, were used respectively. As polishing instruments, diamond point, carbide bur and pink point were used. The uneven images of metal/porcelain interface at parts of tooth top and neck, and middle part of those parts were observed respectively by EPSS analyzer, and the dimensional curves in section at three parts were also measured. The results obtained are as follows. VITA fused to two precious metals was observed to be fully bonded to the surfaces finished by any polishing instruments, and VITA was estimated to be able to get good bonding comparing with DUCERAM. But, in case of nonprecious metal, it was observed from the uneven images that metal/porcelain interfaces of both porcelains were clearly divided, and then this result might be evaluated as by way of the simply mechanical bonding predicted to be lower adhesive strength. The dimensional curves in section at metal/porcelain interface made by skilled and inexperienced dental technicians were distinctly characterized. That of skilled one suddenly varied when shifted from metal location to porcelain location. But, that of inexperienced one did not varied in any parts. Therefore, by measuring the dimensional curve in section using EPSS analyzer, the improvement of new technology in technical work is expected in future.

Dental Alloys↗
PubMed1989

[Application of transbronchial brushing for histological diagnosis of lung cancer].

In order to improve the preoperative diagnostic rate of lung cancer, histological examination was performed by transbronchial brushing in 35 cases, and diagnostic contribution of brushing specimen was compared with that of transbronchial forceps biopsy (TBFB). Histological structures were well preserved in the histology section of brushing specimens, especially in cases of small cell lung cancer. The positive rate of brushing histology was 46%, which was the same as that of TBFB. The total histological diagnostic rate was 66% with simultaneous examination of bronchial brushing and TBFB specimens. Consequently, the use of brushing specimens for histologic evaluation made an additional contribution to the correct positive histology diagnostic rate. Brushing histology is indicated for all types of lung cancer, because in most TBFB-negative cases, biopsies were performed from inappropriate sites of tumors or their materials wer crushed by forceps. It was suggested that concomitant application of brushing specimen for histology examination, contributed to more accurate preoperative histology diagnosis for lung cancer.

Adenocarcinoma↗
PubMed1988

Effects of taxol and colchicine on platelet membrane properties.

The effects of the assembly-disassembly of microtubule on the membrane lipid fluidity, the fragmental motion of sulfhydryl groups of membrane proteins, and the functions of shape change and hypotonic shock response (shrinkage ratio) in human platelets were studied. We have employed electron spin resonance (ESR) utilizing spin labels for bilayer lipids or membrane proteins and microtubule reactive reagents to change microtubule assembly. Both, taxol, a microtubule stabilizing agent, and colchicine, a microtubule disrupting agent, did not affect the platelet membrane lipid fluidity detected by 5- or 16-doxylstearate. On the other hand, the mobility of sulfhydryl groups detected by 4-maleimide-tempo increased by taxol treatment and decreased by colchicine. Moreover, the temperature sensitivity of platelets below 20 degrees C decreased by taxol treatment, but unchanged by colchicine treatment. This behavior was similar to the shape change ability or the shrinkage ratio of platelets pre-treated with taxol, in which microtubule disassembly was inhibited due to taxol binding to microtubule. Therefore, it is confirmed that the assembly-disassembly state of microtubule which may control the ability of platelets to change shape, influences the mobility of sulfhydryl groups in platelet membrane proteins and its temperature sensitivity.

Adult↗
PubMed1988

A case of mediastinal germ cell tumor radically operated on after neoadjuvant chemotherapy-combined resection of the superior vena cava and reconstruction with expanded-PTFE graft.

A case of primary mediastinal germ cell tumor, which was radically treated with reconstruction of the superior vena cava (SVC) after neoadjuvant chemotherapy, is reported herein. This tumor, accompanied with SVC syndrome, was initially unresectably advanced and chemotherapy, using cis-dichlorodiamine-platinum, vindesine and bleomycin, was administered, resulting in a partial response with a 65 per cent tumor regression. The serum human chorionic gonadotropin, which originally had a high value, became reduced in parallel with the tumor regression to within the normal range. Complete tumor resection with reconstruction of the SVC using an expanded polytetrafluoroethylene (EPTFE) graft was successfully performed. The patient has now returned to productive employment and the graft is patent without any clinical symptoms of recurrence, 15 months post-operatively. Neoadjuvant chemotherapy is considered to be vitally important for the treatment of germ cell tumors originating in the anterior mediastinum and an EPTFE graft with external ring support seems to be acceptable as an artificial substitute for SVC replacement.

Adult↗
PubMed1988

[A sensitivity test of UFT and FT-207 against human pulmonary cancer using nude mice].

Transplanted tumors of human pulmonary adenocarcinoma subcutaneously into nude mice were used, to investigate the effect UFT and FT-207. Concentration of 5-FU and uracil in tumors, measured by the gas chromatographic-mass fragment graphic method, was followed. 5-FU concentration in UFT group were higher than other group, and uracil concentration show no significant difference. In one of the lines, tumor growth was stopped in UFT group and regression rate was 68% in comparison with control group, pathologically revealed grade II b in classification of Simosato-Oohoshi. It was also indicated in this experiment, anticancer effect is related with specific anticancer drug sensitivity.

Adenocarcinoma↗
PubMed1988

[A resected case of adenosquamous-carcinoma of the lung].

A resected case of an adenosquamous carcinoma of lung diagnosed from sputum and trans-bronchial-aspiration cytology is reported. The patient, a 39-year-old woman, was identified by mass screening testing for pulmonary cancer. Sputum cytology and trans-bronchial-aspiration cytology conducted by means of a bronchofiberscope revealed the presence of both an adenocarcinoma and squamous carcinoma cells. A histologic examination of the resected lung revealed the adenosquamous carcinoma. This case is very rare in having been diagnosed before surgery, and by sputum cytology which was very available.

Adenocarcinoma↗
PubMed1987

Pathological changes induced by formaldehyde in open-ended rat tracheal implants preexposed to benzo(a)pyrene.

The promotion effects of 0.1% formaldehyde (HCHO) in phosphate-buffered saline (PBS) were tested in rat tracheal implants preexposed to a minimal carcinogenic dose of 468 micrograms benzo(a)pyrene (BAP) released over one month from 865 micrograms BAP-beeswax pellets. At the time of pellet removal, the tracheas were made into open-ended, flow-through, tracheal implants (FTTI), and exposed twice/week to HCHO for 30 weeks. Morphological alterations in the FTTI were monitored biweekly by collection of exfoliated cells from the luminal washings for cytopathologic diagnosis, and periodically by sacrificing animals for histopathology. FTTI exposed to the BAP followed by 30 weeks of HCHO had extensive squamous metaplasia, a high proliferation index of 7.87 [3H]thymidine-labeled cells/mm basement membrane, and foci of moderate and marked atypia. Clear diagnosis of some of the lesions was difficult because of the acute toxic effects of the repeated exposures to HCHO. These effects were seen in the tissues as well as in the exfoliated cells, which attest to the latter as an efficient, non-destructive, method for determining the responses of the tracheas to exposure to toxic and carcinogenic agents. FTTI exposed to BAP followed by twice weekly PBS, had a mostly flattened epithelium, and a low proliferation index (0.39). FTTI exposed to beeswax pellets, followed by the HCHO had a relatively high proliferation index (4.20) in a mucociliary epithelium exhibiting some basal cell hyperplasia. Control FTTI had a normal mucociliary epithelium with a proliferation index of 1.52 [3H]thymidine labeled cells/mm basement membrane.

Animals↗
PubMed1986

Intratumoral ethanol injection for malignant tracheobronchial lesions: a new bronchofiberscopic procedure.

We performed intratumoral ethanol injection via a flexible bronchofiberscope in 13 patients with malignant tracheobronchial lesions in order to evaluate its effects on airway dilatation and hemostasis. The results obtained are described below. Immediately after intratumoral injection of ethanol, bronchofiberscopic findings revealed that the tumor turned faintly white, there was a little regression of tumor, and a promising effect was demonstrated on patients with bleeding from tumors. The injected tumor turned necrotic within several days, and histological examination revealed no viable tumor cells in necrotic tissues. The histological anti-tumor effect of ethanol was also demonstrated in experiments with nude mice. This endoscopic treatment was very effective in polypoid tumor protruding into the tracheobronchial lumen, but ineffective in the case of compressed stenosis or obstruction. In conclusion, intratumoral injection of ethanol is considered to be a promising endoscopic treatment for malignant tracheobronchial lesions.

Adult↗
PubMed1986

[Clinical evaluation of serum NSE and CEA in primary lung cancer patients].

The clinical value of serum neuron specific enolase (NSE) as a tumor marker was evaluated in comparison with simultaneously measured serum CEA, using 74 cases of lung cancers, 13 cases of non-tumorous and non-neurological disease and 28 normal volunteers. The results obtained were as follows: Thirty-five out of the 74 lung cancer cases showed positive serum NSE levels. However, none of the cases of non-tumorous, non-neurological disease and normal volunteers demonstrated more than 10ng/ml NSE which was significantly different from the results of lung cancer cases. We found a higher degree of NSE positiveness in cases of small cell carcinoma than in cases of other histological types. However, no obvious difference of CEA positiveness between any histological types was revealed. Both serum NSE and CEA showed an increase in positive rate in parallel with the progress of stages, including 80.4% of cases of stages III and IV disease which had positive serum levels of both or either of the two markers. However, we could not find any obvious correlation between serum NSE and CEA. The serum levels of both markers clearly decreased after surgery, serum CEA level being considered to be a better reflection of host tumor burden than NSE. In conclusion, the simultaneous testing of serum NSE and CEA is considered to be very useful for evaluating the clinical course or the effect of cancer therapy in lung cancer patients, with higher specificity and sensitivity.

Adenocarcinoma↗
PubMed1985

[Percutaneous fine needle biopsy for malignant mediastinal tumors].

Seventeen patients with mediastinal malignant tumors (four neurogenic tumors, four thymomas, three germ cell tumors, two malignant lymphomas and one each of carcinoid, malignant melanoma, multiple myeloma and carcinoma simplex) were examined for the evaluation of percutaneous fine needle biopsy. In 16 cases of them, adequate materials for cytodiagnosis were obtained. Fifteen of the 17 cases (88%) were positive for malignant cells, and 1 case was negative. As for the histological types, 9 cytological diagnoses (60%) were compatible and 4 diagnoses (27%) were not. Regarding complications of percutaneous fine needle biopsy, 1 case of subcutaneous needle tract implantation was noted. Percutaneous fine needle biopsy is strongly recommended for diagnosis of mediastinal tumors.

Aged↗
PubMed1984

Adjuvant immunotherapy of primary resected lung cancer with transfer factor.

One hundred seventy-one patients were studied in order to evaluate the clinical efficacy of the transfer factor (TF) for primary resected lung cancers under a randomized controlled trial. Eligible cases for evaluation were randomly chosen at 75 and 74 patients in TF and control groups, respectively. The same long-term intermittent adjuvant chemotherapy was administered to two groups as a standard therapy. The distribution of clinical features in both groups was very similar. The overall survival rates of the TF group at 2 and 4 years postoperatively were 69% and 53%, respectively, which was about 15% better than the control group, but this difference could not yet be considered statistically significant. The survival of the TF group was significantly better than that of the control group in patients with Stages I + II or curative resection (P less than 0.05 by Cox-Mantel test); however, there was no significant difference in patients with Stages III + IV, or noncurative resection. The recurrence rate of pulmonary and mediastinal regions was less in the TF group. In conclusion, TF seems to suppress postoperative recurrence and appears to be beneficial for primary resected lung cancer patients, especially at early stages, as postoperative adjuvant immunotherapy.

Adult↗