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Biomedical subjects

Y Nagashima

Publications and source records attributed to Y Nagashima.

At least 145 records · Page 8Linked to original sources
PubMed1996

Development of an ultra high sensitive tissue biosensor for determination of swellfish poisoning, tetrodotoxin.

A simple tissue biosensor for measuring Na+ channel blockers such as tetrodotoxin (TTX) and saxitoxin (STX) has been developed. The membrane of frog bladder has Na+ channels which control the passage of Na+. It is well known that TTX blocks Na+ channels. The tissue biosensor consists of a Na+ electrode integrated within a flow cell. The tip of the electrode was covered with frog bladder membrane sandwiched between two sheets of cellulose acetate membrane, and the electrode was set in a flow cell. A solution of 8% NaCl was carried in the cell and the output of the electrode allowed to stabilize. TTX was injected into the sensor system and measured from the inhibition ratio of the sensor peak output. One assay took approximately 5 min. The lower limit of detection was 86 fg. The continuous determination of TTX was feasible for 250 h in the presence of 0.003% NaN3. A Linear correlation was obtained between TTX activities of F-niphobles and F-parudale determined by the methods of TTX sensor and mouse assay.

Animals↗
PubMed1996

Negative chronotropic and inotropic effects of U-92032, a novel T-type Ca2+ channel blocker, on the isolated, blood-perfused dog atrium.

We investigated the effects of U-92032 ((7-((bis-4-fluorophenyl) methyl)-1-piperazinyl)-2-2(2-hydroxyethylamino)-4-(1-methylethyl)- 2,4, 6-cycloheptatrien-1-one), a novel T-type Ca2+ channel blocker, on sinus rate and atrial contractile force in the isolated, blood-perfused atrium of the dog. U-92032 (1 to 300 nmol) induced negative chronotropic and inotropic responses in a dose-dependent manner, and the percentage decrease in sinus rate was less than that in atrial contractile force. Atropine did not affect the negative responses to U-92032. These results suggest that U-92032, a T-type Ca2+ channel blocker, simultaneously decreases the sinus rate and atrial force as do L-type Ca2+ channel blockers in the isolated dog atrium.

Analysis of Variance↗
PubMed1996

A rare case of ectopic antidiuretic hormone-producing pancreatic adenocarcinoma: new diagnostic approach.

We describe a 73-year old man with the syndrome of inappropriate antidiuretic hormone secretion (SIADH) due to an ectopic ADH-producing pancreatic adenocarcinoma. His laboratory findings showed marked hyponatremia, and the water load test showed uncontrolled ADH secretion. The imaging studies revealed pancreatic body cancer. Histological examination revealed an adenocarcinoma of the pancreas, which was positive for ADH immuno-staining. The ADH in the tumor extract was 53.3 pg/g wet weight. In attempt to diagnose ADH-production from the tumor, the ADH in his pancreatic juice was measured and found to be 2.1 pg/ml. We conclude that it is valid to measure the ADH in pancreatic juice to diagnose ectopic ADH production by tumors.

Adenocarcinoma↗
PubMed1996

[A case of alpha-fetoprotein producing mediastinal germ cell tumor treated with preoperative chemotherapy].

A 20-year-old male was treated with 3 courses of cisplatin combined chemotherapy, with a clinical diagnosis of mediastinal germ cell tumor. Although alpha-fetoprotein (AFP), which alone had been high (893 ng/ml on admission) among tumor markers examined, normalized after chemotherapy, the size of the tumor remained unchanged. The patient underwent total resection of the tumor and has been followed with no evidence of recurrence for 18 months. Pathological examination suggested that the tumor was an immature teratoma with extensive proliferation of fibrous element. Neither other elements of germ cell tumor nor AFP producing cells were found. Preoperative chemotherapy is usually effective in treatment of germ cell tumors. However, it is important to recall that measurements of tumor volume occasionally do not provide information on the tumor's response.

Adult↗
PubMed1996

[Limited operation and simple lobectomy for primary lung cancer in poor risk patients].

During the years 1990 to 1994, 54 poor risk patients were performed relative noncurative operation for primary lung cancer, such as limited operation or lobectomy without mediastinal lymphnodal dissection. The indication for lesser resection were mainly cardiopulmonary diseases and the elderly over 75 years old. 3 were bilobectomies, 32 were lobectomies, 1 was lobectomy and segmentectomy, 10 were segmentectomies, 8 were wedge resections. The number of cases with stage I were 41 (75.9%). Postoperative complications occurred in 13 patients (24.1%). The overall 5-year survival rate was 63.5%. The 5-year survial rate of p 0 approximately p 1, pN 0 cases was 73.9%. Relative noncurative cases undergoing lesser resection showed relatively good result compared to standard lobectomy. It was considered that lesser resection for such poor risk patients with stage I can be a beneficial therapeutic modality.

Adenocarcinoma↗
PubMed1996

[Unilateral and synchronous occurrence of renal cell carcinoma and ureteral tumor: a case report].

An 81-year-old woman was admitted to our hospital with left flank pain. Excretory urography revealed left hydronephrosis. Abdominal computed tomography (CT) revealed a large heterogenous tumor in the upper pole and marked hydronephrosis and hydroureter in the lower portion of the left kidney. Left total nephroureterectomy was performed under the diagnosis of renal pelvic and ureter tumor. The pathological diagnosis was of renal cell carcinoma (spindle type, grade 3) in the kidney and transitional cell carcinoma (grade 2) in the ureter. Postoperative chemotherapy was not given. Convalescence was uneventful and fifteen months after the operation she is alive with no recurrence or metastasis.

Aged↗
PubMed1995

Trypsinogen expression in human ovarian carcinomas.

Increased secretion of matrix metalloproteinases and serine proteinases is well known to be associated with cancer invasion and metastasis. We aimed to elucidate the implication of trypsin, a serine proteinase and a representative digestive enzyme in invasion and metastasis of human carcinomas. Northern blot, RT-PCR and Western blot analyses and immunohistochemical studies were performed to detect and analyze trypsinogen expression in 5 ovarian carcinoma cell lines and 10 human ovarian carcinoma tissues using a DNA probe for trypsinogen I, and monoclonal and polyclonal antibodies to human trypsin I. Among the 5 ovarian carcinoma cell lines, only the MCAS (mucinous cystadenocarcinoma) cell line showed a high level of trypsinogen production and mRNA expression by Western and Northern blot analyses, respectively. However, Southern blot analysis of RT-PCR products could detect considerable levels of trypsinogen mRNA in all ovarian cancer cell lines. In Northern analysis of ovarian cancer tissues, all advanced cancer samples showed trypsinogen gene expression. Serous cystadenocarcinomas exhibited particularly high levels of gene expression. Immunohistochemical staining also detected trypsin in ovarian carcinoma tissues. In contrast, normal ovaries and tumors with low malignant potential did not show trypsinogen expression. Our results demonstrate the extra-pancreatic production and distribution of trypsinogen in human ovarian carcinomas.

Adenocarcinoma↗
PubMed1995

A novel insertion sequence (IS)-like element of the thermophilic bacterium PS3 promotes expression of the alanine carrier protein-encoding gene.

A novel insertion sequence (IS)-like element was found in the 5'-upstream region of the alanine carrier protein-encoding gene (acp) in the thermophilic bacterium PS3 chromosomal DNA. The sequence contained an open reading frame (ORF) encoding a polypeptide of 369 amino acids which revealed high similarity with ORFs from IS891 from the cyanobacterium Anabaena and IS1136 from Saccharopolyspora erythraea. The direction of transcription was the same as that of acp, and typical inverted and direct repeats characteristic of IS were found in both the 5' and 3' region of the ORF. Southern hybridization analysis of the chromosomal DNA revealed that multiple copies of the ORF sequence were contained in the PS3 genome. This element might well be a member of a new IS family including IS891 and IS1136, and we have designated this element IS1341. The analysis of acp expression in Escherichia coli cells indicated that IS1341 promotes the expression of acp.

Amino Acid Sequence↗
PubMed1995

Establishment and characterization of two human ovarian clear cell adenocarcinoma lines from metastatic lesions with different properties.

Two permanent human ovarian clear cell adenocarcinoma lines (OVISE and OVTOKO) were established from metastatic tumors of two patients who were treated with five to six courses of CAP chemotherapy. The two cell lines grow on monolayers and showed a variety in both size and shape: small or moderately sized cuboidal cells, columnar cells, spindle-shaped cells, and malignant tumor giant cells. The cell lines have been in culture for 4 to 6 years, the passage number varying from 160 to 220. The mean population-doubling time of the two cells was 60 to 70 hr. The OVISE cells shed tumor-associated antigens CA19-9, CA125, and TPA in the culture medium, whereas the OVTOKO cells did not secrete them at detectable levels. Immunohistochemical analysis showed that coexpression of cytokeratins and vimentin was preserved in the two cell lines, which is a feature of cultured epithelial origin. Cytokeratin polypeptides 7, 8, 18, and 19 were expressed in both cell lines. The EGF receptor was more intensely expressed in the OVTOKO cells than in the OVISE cells. The estrogen and progesterone receptors were negative in both cell lines. The two cell lines showed no chemosensitivity to anticancer drugs including cisplatin, doxorubicin, cyclophosphamide, and etoposide. Heterotransplantation of the two cell lines reflected the origin of cells. Intraperitoneal transplantation of the OVTOKO cells yielded peritoneal implantation and distant metastasis, whereas that of the OVISE cells showed no dissemination and metastasis. These new ovarian clear cell adenocarcinoma lines will provide a relevant experimental system for further investigations into the intrinsic alterations responsible for malignant progression and chemoresistance.

Adenocarcinoma, Clear Cell↗
PubMed1995

Marked induction of gelatinases, especially type B, in host fibroblasts by human ovarian cancer cells in athymic mice.

Two human ovarian adenocarcinoma cell lines, MCAS-3 and OVISE-3 were found to secrete little of any type of gelatinase in tissue culture. However, when these cell lines were implanted subcutaneously into nude mice the cyst fluids from the resultant tumors contained gelatinase A and/or B. The enzyme activities, especially of gelatinase B, were much higher in the malignant MCAS-3 tumors than in those of the less malignant OVISE-3 tumor cells. To elucidate the origin of gelatinase B in cyst fluids of the MCAS-3 tumors, murine skin fibroblasts (MSF) were isolated from a subcutaneous tumor in a nude mouse and tested for their proteinase secretion in culture. MSF cells, which secreted some gelatinase A and gelatinase B, were induced to secrete high levels of both enzymes, especially gelatinase B, by co-cultivation with MCAS-3 cells. In addition, gelatinase A activity was induced by incubation of MSF cells with the conditioned medium of either MCAS-3 or OVISE-3 cells, whereas gelatinase B was induced only with that of MCAS-3. Although cytokines or growth factors such as IL-1 beta, TGF-beta 1, TNF-alpha or EGF stimulated the secretion of gelatinases A and B from MSF cells, their effects on gelatinase B activity were far less than that of the MCAS-3 conditioned medium. These results indicate that the major part of gelatinase B activity in the cyst fluids of the ovarian tumors is secreted by host interstitial cells stimulated by tumor-derived humoral factors. Similar tumor cell-host cell interactions may be important in the production of various proteinases in other tumor types.

Animals↗
PubMed1995

Detection of a proteinaceous toxin in the brackishwater clam (Corbicula japonica).

Water extracts from the brackishwater clam (Corbicula japonica) were found to be lethal to mice upon i.v. injection. Muscular tissues (foot muscle, adductor muscle, mantle muscle, mantle and siphon) were all toxic while gill and viscera (mid-gut gland, testis and ovary) were nontoxic; the highest toxicity was observed with foot muscle. The toxin was judged to be a thermolabile, basic protein with a mol. wt. of about 13,000.

Animals↗
PubMed1995

Establishment of two rat osteosarcoma cell lines (YROS-1 and YROS-2) induced by radioactive phosphorus.

Two rat osteosarcoma cell lines, YROS-1 and YROS-2, were established from two experimental osteosarcomas and induced by internal irradiation with radioactive phosphorus. Both cell lines formed a monolayer cell sheet in vitro with focal piling. The YROS-1 cells were refractile and spindle or polygonal in shape, whereas the YROS-2 cells were flat, spread and polygonal in shape. Ultrastructurally, the YROS-1 cells had well-developed rough-surfaced endoplasmic reticulum with focal pericellular deposition of calcified matrix, whereas YROS-2 had abundant polysomes and intracytoplasmic filaments. Both cell lines grew stably with population doubling times of 23 and 39 h, respectively. Flow cytometry revealed that YROS-1 was rich in proliferating cells compared to YROS-2, with a higher colony-forming efficiency. YROS-1 showed high alkaline phosphatase activity, while YROS-2 possessed low activity. When subcutaneously transplanted into lumbodorsal area of athymic nude mice, only YROS-1 formed tumors with frequent lung metastasis.

Animals↗
PubMed1995

Renal oncocytoma containing "chromophobe" cells.

We report a rare case of renal oncocytoma containing occasional "chromophobe" cells. This case suggests an intimate relationship between oncocytoma and "chromophobe" renal cell carcinoma.

Adenoma, Oxyphilic↗
PubMed1995

[Clinico-pathological aspect of HIV-sero positive inpatients].

To describe the clinico-pathological aspect of HIV/AIDS inpatients, we reviewed HIV/AIDS inpatients in our hospital since 1988. We evaluated risk factors, CD4 counts, CD4/8 ratio, cause of death and the survival time after diagnosis of AIDS. A total of 13 HIV sero-positive subjects were admitted to our hospital, including 11 cases (85%) with AIDS. One patient was a foreigner. All cases were male; age range 18-70 years. Hemophiliacs and sexually transmitted patients account for 62% and 38% of cases, respectively. There were no cases of intravenous drug users. In all cases with AIDS, CD4+ cells and CD4/8 ratio significantly decreased with median value of 73/microns and 0.18, respectively. Six cases (54%) were decreased and autopsy were done in four cases. Findings of autopsy revealed HIV encephalopathy and systemic various infection, including Pneumocystis carinii, cytomegalovirus, papilloma virus and pox virus. Cytomegalovirus infection was found in all cases; one had innumerable inclusion bodies in lung, adrenal gland and intestines. The median survival time after diagnosis of AIDS were 26 months.

AIDS-Related Opportunistic Infections↗
PubMed1995

Localization and activity of adrenal carbonyl reductase during the estrous cycle.

Changes in carbonyl reductase (CR) activity towards seven substrates in adrenal glands of female rats were investigated during estrous cycle and the circadian patterns of adrenal CR activity towards seven substrates in male rats were examined. The localization of the enzyme protein in the adrenal gland was carried out by immunohistochemistry. In female rats, adrenal CR activity was lowest between 1200 and 2000 h on the day of proestrus, the phase in which a large, significant increase in ovarian steroids, gonadotropins and prolactin is observed. Immunoreactivity in the zona reticularis of the adrenal cortex to anti-adrenal CR, CR-K2, antibody on the day of proestrus was faint or negative compared with that on other days of the estrous cycle. In male rats, no major changes in adrenal CR activity were observed compared with females, although these were slight changes in all the enzyme activities. These results suggest that adrenal CR may be negatively regulated by the pituitary-adrenal axis in female rats and, in particular, on the day of proestrus.

Adrenal Glands↗