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Biomedical subjects

T Tsuzuki

Publications and source records attributed to T Tsuzuki.

212 records · Page 12Linked to original sources

Response of the human larynx to silicone.

This report is concerned with tissue reaction to silicone and, in particular, long-term foreign body reaction. A histopathologic study was done on the larynx of a patient who had been injected 12 years before in the right vocal fold with room temperature vulcanizing silicone. The examination revealed particles of silicone encapsulated by thin fibrous tissue. There were few giant cells of the foreign body type and little cell infiltration. In addition, a questionnaire was returned by 54 of 90 patients who had vocal fold injected with less than 1.5 mL of either silicone fluid or room temperature vulcanizing silicone in the vocal fold from 1977 to 1984. Of these 54 patients, there was no occurrence of laryngeal disease, carcinoma, and/or connective tissue disease after the silicone injection. These findings attest to the safety of silicone in the small amounts used to treat vocal cord paralysis.

Foreign-Body Reaction↗

Voice prognosis after liquid and solid silicone injection.

A study was undertaken to determine the voice prognosis in 51 of the 408 patients with unilateral recurrent laryngeal nerve paralysis who had visited the Department of Ear, Nose and Throat at Keio University between 1977 and 1984. The 51 patients were divided into three groups: 18 patients without silicone injection, 15 with a silicone liquid implant, and 18 with a silicone solid implant. Data are provided to show that (1) both types of silicone implant are tolerated by the body and effective in improving voice and that (2) the liquid implant is ultimately absorbed and therefore useful for temporary voice improvement in patients in whom the prognosis for vocal fold paralysis is not known, whereas the solid implant is not absorbed and is therefore effective in the long term when recovery can be ruled out.

Adult↗

Photostable chlorophyll a conjugated with poly(vinylpyrrolidone)-smectite catalyzes photoreduction and hydrogen gas evolution by visible light.

Chlorophyll a was adsorbed to a synthetic smectite intercalated by poly(vinylpyrrolidone) (PVP) to form the chlorophyll-PVP-smectite conjugate (Chl-PVP-SME) having an absorption maximum at 677 nm. The conjugate was found to be stable toward light illumination in comparison with chlorophyll-smectite, chlorophyll-PVP, and free chlorophyll a. Chl-PVP-SME had a photoinduced activity for catalyzing the reduction of methyl viologen. Furthermore, the evolution of hydrogen gas was observed when an aqueous suspension containing Chl-PVP-SME, methyl viologen (an electron carrier), 2-mercaptoethanol (an electron donor), and hydrogenase was illuminated by visible light.

Bacterial Proteins↗

Effects of low lead exposure on neuro-behavioral function in the rat.

Small doses (45-180 micrograms/g) of lead acetate were administered to male rats by gavage every day during the first 3 wk of life. A blood concentration of approximately 59 micrograms/100 ml blood produced signs of disturbances in reflex development and some changes in emotional behavior. Larger doses resulted in subtle changes in the neuromotor coordination function. The effect of low levels of lead exposure on the cognitive function in operant conditioning could not clearly be observed. Brain lead concentration tended to be higher than in other tissues examined. At approximately 10 months following cessation of lead acetate administration, the brain lead concentration had decreased to almost the same level found in control rats, and no distinguishable differences were observed between the lead-treated rats and controls in emotional behavior and neuromotor coordination.

Animals↗

A phase II multicentric trial of S-1 combined with 24 h-infusion of cisplatin in patients with advanced gastric cancer.

BACKGROUND: The aim of this multicentric trial was to determine the clinical toxicities and antitumor effects of a chemotherapy regimen of S-1 combined with cisplatin in patients with inoperable locally or metastatic advanced gastric cancer. PATIENTS AND METHODS: Forty-two patients were entered into the study. S-1 (80 mg/m2) was administered orally daily for 14 consecutive days and 24-h infusion of cisplatin (70 mg/m2) was administered on day 8 of every 28-day cycle. RESULTS: The overall response rate was 50% and complete response rate was 5%. The most common adverse event was leucopenia, which occurred with grade 3 in 7 patients (16.6%) and grade 4 in 2 patients (4.8%). Non-hematological adverse events were generally mild. The median survival time was 342 days. The 2-year survival rate was 22.9%. CONCLUSION: This combination chemotherapy is active, convenient and well tolerated in patients with high-grade advanced gastric cancer.

Adult↗

Pathological study of lead poisoning in whooper swans (Cygnus cygnus) in Japan.

During spring 1989, thirty-three whooper swans (Cygnus cygnus) died at Lake Miyajima in Hokkaido, Japan; 15 were examined. The birds were diagnosed as having subacute lead poisoning due to ingestion of spent lead shot. The main gross findings were bile-stained liver, edematous or gelatinous bone marrow, bile-stained lining with hyperkeratosis and lead pellets in the gizzard, and proventricular impaction. Histopathologically, there was lead-hemolytic jaundice of the liver, hemosiderosis in the liver and spleen, and hypoplasia of the bone marrow with increased numbers of polychromatic erythroblasts. Acid-fast intranuclear inclusion bodies were seen in kidneys of seven swans. Under electron microscopy, inclusion bodies had frayed contours and consisted of high-electron-dense fine granules. The lead concentration of the liver ranged from 5.5 to 44.3 mg/kg wet weight. It was suggested that these changes resulted from excess breakdown of erythrocytes, inhibition of heme synthesis, and impaired erythropoiesis caused by lead shot.

Animals↗

Marked induction of HSP47, a collagen-binding stress protein, during solid tumor formation of ascitic Sarcoma 180 in vivo.

HSP47, a heat shock-inducible glycoprotein of Mr = 47,000, is assumed to be a molecular chaperone specific for collagen. In addition to its stress inducibility, HSP47 has transformation-sensitivity; that is, the synthesis of HSP47 decreases after malignant transformation. We developed a rat monoclonal antibody against mouse HSP47, which we then used to examine the amounts of HSP47 in transplanted tumors. HSC70 (HSP73) was expressed constitutively in these ascites as well as solid tumors. While HSP47 was not expressed in ascitic form of Sarcoma 180, its expression was markedly induced during solid tumor formation of ascitic Sarcoma 180 cells after subcutaneous transplantation. The average survival period of ascites Sarcoma 180-bearing mice was 20.3 +/- 3.6 days (mean +/- SD), and was much shorter than that of solid Sarcoma 180-bearing mice. These findings suggest an important role of HSP47 in solid tumor formation as well as a possible marker for tumor malignancy.

Animals↗

Inhibition of HSP47 during the transition from solid to ascitic form of Sarcoma 180 in vivo.

HSP47, a collagen-binding stress protein, has transformation-sensitivity; that is, the synthesis of HSP47 decreases after malignant transformation. We examined the expression of HSP47 in transplanted tumours by Western blotting. While HSP47 was not detected in ascites tumours including Ehrlich, P388 and Sarcoma 180, marked expression of HSP47 was observed in solid tumours such as B16, B16-BL6 and Sarcoma 180. The expression of HSP47 in Sarcoma 180 cells disappeared completely after these solid tumour cells were dispersed and inoculated intraperitoneally. These findings suggested an important role of HSP47 as a marker for tumour malignancy.

Animals↗

Decreased expression of HSP47 in highly malignant mouse fibrosarcoma.

HSP47, a heat shock-inducible glycoprotein of M(r) = 47,000, is assumed to be a molecular chaperone specific for collagen. In addition to its stress inducibility, HSP47 has transformation-sensitivity; that is, the synthesis of HSP47 decreases after malignant transformation. The expression of several HSPs in mouse fibrosarcoma, QRsP-1 and QRsP-4 were examined. HSP47 expression was weaker in the highly malignant QRsP-4 than in the weakly malignant QRsP-1, whilst HSC70 expression was similar in both cell lines. These findings suggested an important role of HSP47 as a marker of tumour malignancy of QRsP cell lines.

Animals↗

Specific expression of HSP47 in human tumor cell lines in vitro.

HSP47 is a stress-inducible glycoprotein of 47 kd molecular weight, and is assumed to be a collagen specific molecular chaperone. The expression of HSP47 is closely related to that of collagen, which is the main component of the extracellular matrix. We investigated the expression level of HSP47 in human tumor cell lines to elucidate collagen biosynthesis in tumor cells. Western blot analysis showed higher levels of HSP47 in solid tumor cell lines than in leukemia cell lines. Tumor cell lines which were derived from metastatic carcinomas and were still metastatic in animals, synthesized higher levels of HSP47. These results suggested that HSP47 may play an important role in tumor metastasis and can be a prognostic marker for the metastatic activity of human tumor cells.

Animals↗

Specific expression of HSP27 in human tumor cell lines in vitro.

The cells of all organisms respond to environmental stress by synthesizing a specific group of proteins called heat shock proteins (HSPs). While the protective role of HSPs has been observed against cellular stress, recent reports have suggested a number of functions of HSPs in various cellular processes in normal and pathological conditions. HSP27 is an important low molecular weight HSP (Mr: 27,000) found in human cells. HSP27 appears to be involved in intracellular signaling and drug resistance in addition to thermotolerance. In human breast tumors, a striking association between HSP27 overexpression and a shorter disease-free survival period was reported. In this paper, we evaluated the expression levels of HSP27 in the cell lines of human breast and other tumors. Western blotting of HSP27 has shown the correlation of HSP27 expression and metastasis and tumorigenicity of mammary and prostate tumors. Thus the biological significance of HSP27 in aggressive mammary and prostate tumors was indicated. HSP27 is suggested to be a prognostic marker for the malignancy of mammary and prostate tumors.

Animals↗

Specific regulation of HSPs in human tumor cell lines by PSK.

Substantial progress has been make in elucidating the biochemical properties of HSPs (Heat Shock Proteins) as molecular chaperones in protein biogenesis and their roles in thermoprotection and cytoprotection against cellular insults. Recently, besides advantageous cellular functions, the detrimental role of HSPs has been implicated in a variety of diseases. HSP47 is assumed to be a collagen specific molecular chaperone and its involvement in the progression of fibrosis was observed. There have been a number of reports that suggest the role of HSP60 as an autoantigen in a variety of autoimmune diseases. PSK, a protein-bound polysaccharide, is a biological response modifier that is clinically used for the treatment of cancer patients in Japan. PSK shows a broad range of biological effects in addition to the antitumor activity. In this study, we evaluated the effect of PSK on the expression of HSPs in human tumor strains at the protein and mRNA levels. PSK was observed to suppress the expression of HSP47 and HSP60 but not HSP72/73 in human tumor cell lines. Thus, the novel pharmacological potential of PSK was suggested in the diseases derived from the aberrant expression of HSPs.

Animals↗

Specific regulation of HSPs in human tumor cell lines by flavonoids.

While the protective role HSPs (Heat Shock Proteins) has been recognized against physiological stress such as heat shock, heavy metals and glucose starvation, recent progress has revealed another aspect of HSPs in various diseases. HSP27 has been shown to be involved in the acquired resistance of tumor cells hyperthermic and chemotherapeutic treatment. In human breast tumors, overexpression of HSP27 is associated with a shorter disease-free survival period. HSP47 is thought to be a collagen specific molecular chaperone. The involvement of HSP47 in the progression of fibrosis has been reported. Aberrant expression of HSP could cause various autoimmune diseases. Manipulation of HSP expression, therefore, could be a therapeutic target to reduce HSP-derived detrimental cellular effects. Flavonoids are a widely distributed group of plant substances, universally present in vascular plants. Although the flavonoids have been known as natural plant products as long as the alkaloids, their pharmacological effects and potential medicinal uses have been little studied by comparison. Today, the picture has changed and the biological and pharmacological activities of plant flavonoids look promising. We investigated the effect of flavonoids on the expression of HSPs in human tumor cell lines. Flavonoids inhibited the expression of HSP27, HSP47, HSP60 and HSP72/73. The results suggested the pharmacological possibilities of flavonoids in diseases derived from abnormal expression of HSPs.

Animals↗