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Y Tomooka

Publications and source records attributed to Y Tomooka.

At least 37 records · Page 2Linked to original sources

DRG: a novel developmentally regulated GTP-binding protein.

Using a subtraction cloning approach we had previously isolated a series of murine cDNA clones representing the genes predominantly expressed in the embryonic brain and down-regulated during development. We now report that one of these cDNA clones encodes a novel type of GTP-binding protein. The predicted protein of 40.5 kD, named DRG, contains five structural motifs characteristic of the GTP-binding proteins. Consistently, bacterially expressed and cellular DRG proteins are capable of binding GTP in vitro. Sequences closely related to the DRG protein are found in other species including Drosophila and Halobacterium. Based on these observations, we propose that DRG represents an evolutionarily conserved novel class of GTP-binding protein which may play an important role in cell physiology.

Aging↗

Expression of DRG during murine embryonic development.

We had previously characterised a cDNA which encodes a novel GTP-binding protein DRG. The expression of drg gene is down-regulated during the embryonic development of murine central nervous system. Further analysis of drg mRNA and protein in adult mouse tissues and various cell lines of different origins indicated that it is expressed widely, albeit at low and variable levels. In situ hybridisation analysis of mRNA expression in sections of mouse embryos indicated that drg is expressed strongly in various embryonic tissues. The expression of drg mRNA is greatly reduced in newborn animals. At cellular level, DRG protein can be detected in the cytoplasm. These observations suggest that DRG may play multiple roles in development and normal cell metabolism.

3T3 Cells↗

Identification of a developmentally regulated gene in the mouse central nervous system which encodes a novel proline rich protein.

A full length cDNA whose corresponding mRNA is down-regulated during the mouse embryonic brain development was isolated. The cDNA contains a single long open reading frame which could encode a protein with relative molecular mass of 41 kDa. The predicted gene product contains long stretches of prolines towards the NH2-terminus, followed by a leucine/proline rich region. The cDNA probe detected a number of mRNA species in Northern blot analysis. The reverse transcriptase-polymerase chain reaction analysis of mRNA from adult mouse tissues indicated that heart and testis expressed this gene (named NDPP-1) at relatively high levels, while lower levels of mRNA were detected in a number of other tissues. Expression of NDPP-1 was also detected in embryonic carcinoma and pheochromocytoma cell lines, but not in fibroblasts. The cDNA hybridized to genomic DNA from several vertebrates species in Southern blot analysis indicating interspecies conservation of this gene. The interesting pattern of expression of the NDPP-1 gene during mouse brain development and the structure of its putative protein product indicate that this gene may play an important biological role in the development of mouse central nervous system.

Animals↗

Identification of a set of genes with developmentally down-regulated expression in the mouse brain.

Using a subtraction cloning approach, we have isolated a set of cDNA clones from mouse neural precursor cells whose respective mRNA levels are down-regulated during the development of mouse brain. Single stranded DNA prepared from neuronal precursor cell cDNA library in lambda Zap vector was subtracted with poly (A)+ RNA prepared from postnatal and adult mouse brain to obtain several clones which show developmental down-regulation of expression. Their patterns of expression indicate that these genes may play important roles during the embryonic development and differentiation of central nervous system.

Aging↗

[Spontaneous peripelvic extravasation associated with primary ureteral tumor: a case report].

A case of spontaneous peripelvic extravasation associated with primary ureteral tumor is reported. A 56-year-old woman presented with left flank pain. Excretory urogram and abdominal computed tomographic (CT) scan demonstrated left hydronephrosis with extravasation of contrast materials around the renal pelvis. Retrograde pyelogram showed the filling defect in the left upper ureter. Under diagnosis of ureteral tumor, total nephroureterectomy was performed. Histological findings revealed transitional cell carcinoma. 80 cases of spontaneous peripelvic extravasation in Japan were reviewed and discussed briefly.

Carcinoma, Transitional Cell↗

Secretion of polypeptides related to epidermal growth factor and insulinlike growth factor I by a human teratocarcinoma cell line.

To identify polypeptide growth factors for human teratocarcinoma cells, we studied the malignant ovarian teratoma-derived cell line, PA-1, that grew autonomously in serum-free medium. Medium conditioned by undifferentiated PA-1 cells strongly stimulated proliferation of the mouse mammary tumor cell line, GR 2H6, which is responsive to epidermal growth factor (EGF) and insulinlike growth factor-I (IGF-I). After ammonium sulfate precipitation, PA-1 conditioned medium was analyzed by anion exchange chromatography and bioassay of elution fractions on GR 2H6 cells that were grown in medium deficient in either EGF or insulin. The results demonstrated that PA-1 CM contained factors that can substitute for EGF and IGF-I in stimulating growth of GR 2H6 cells. Western blots of peak mitogenic fractions revealed low molecular weight polypeptides that were immunoreactive with either anti-EGF or anti-IGF-I antibodies. Indirect immunofluorescence staining of PA-1 cells with monoclonal antibodies localized receptors for each growth factor, and binding of human EGF and IGF-I to these cells was quantified by radioreceptor assays. Secretion of factors closely related to EGF and IGF-I by PA-1 cells under serum-free conditions may provide a novel model system to study molecular mechanisms of autocrine growth stimulation in teratocarcinomas.

Animals↗

Isolation and characterization of mouse neural precursor cells in primary culture.

Primary cultures of mouse neural precursor cells were established by enzymatic dissociation of embryonic Day 10 fetal heads followed by negative selection of non-neural contaminating cells. The latter were allowed to attach and spread on a plastic substrate under conditions that permitted neural precursor cells to remain suspended in the culture medium. The resulting neuroepithelial cell enriched suspension then was plated on dishes coated with poly-D-lysine. Growth of fibroblastic cells was inhibited in a selective medium. Cell proliferation was measured by immunoperoxidase staining of nuclei after bromodeoxyuridine labeling. The proportion of labeled cells declined from 50% on Day 1 until Day 5 when it approached zero, and after 7 days in culture a fourfold increase in cell number was achieved in medium containing 1% fetal bovine serum, transferrin, insulin, cholera toxin, and sodium selenite. Differentiation of neural precursor cells was studied by indirect immunofluorescence microscopy for the appearance of neuron- and astrocyte-specific cytoskeletal proteins at successive intervals in culture. Cells bearing neuritic processes and expressing neurofilaments as well as microtubule-associated protein 2 were present in low numbers on Day 1, increasing through Day 14. Stellate cells with morphologic features of astrocytes and immunoreactive for glial fibrillary acidic protein were not detected until Day 5 and did not become abundant until Day 11. No differences in morphology or immunocytochemical staining characteristics were found between neural precursor cells processed by enzymatic dissociation of whole fetal heads and those recovered by manual dissection of fetal neuroepithelia. The large number of neural precursor cells obtained by this rapid, simple method makes possible the production of mass cultures for molecular analysis of the regulatory factors that control proliferation and differentiation during early development of the mouse central nervous system.

Animals↗

[Rectal metastasis of prostatic cancer causing annular stricture: a case report].

A 61-year-old man diagnosed with poorly differentiated adenocarcinoma of the prostate (T4 NxM0, stage C) underwent endocrine therapy. The reduction of the tumor was recognized but soon annular rectal stricture appeared. In spite of the subsequent chemotherapy, symptoms aggravated. Then total pelvic exenteration and colostomy were performed. Prostate was easily separated from the rectal wall and the tumor continuity was not proved. Immunohistochemical inspection indicated that the origin of the tumor cells of the rectum was the prostate. Histopathological examination of the rectum using the step section method showed no trace of cancer invasion but many cancer cells in the intramural lymphatic duct. We concluded that adenocarcinoma of the prostate metastasized to the rectum by way of lymphatic flow and caused the annular stricture of the rectum.

Adenocarcinoma↗

[Upper urinary tract tumors following bladder cancer].

We treated in total 795 patients with primary transitional cell carcinoma of the urinary bladder between April, 1964 and December, 1988. Eighteen patients of them had upper urothelial cancer during the follow-up period. Thirteen of the 18 patients had received transurethral resection for the initial bladder cancer, while 3 total cystectomy and 2 segmental resection. The over-all incidence of bladder cancer patients who subsequently developed upper urinary tract tumors was 2.3 per cent. The interval between initial treatment of the bladder cancer and treatment for the upper urinary tract tumor ranged from 2 to 74 months (median 20 months). The five-year survival rate after treatment for the upper urinary tract tumor was 31.7 per cent. We conclude that the following are high risk patients for development of upper urinary tract recurrences: 1) patients with bladder cancer near orifices, 2) patients with recurrent bladder cancer under bladder preserving treatment for a long time, 3) patients with G2 multifocal bladder cancer.

Aged↗

[Production of monoclonal antibodies against human bladder cancer cells and application to immunohistochemical analysis of bladder cancer].

Two hybridomas secreting two monoclonal antibodies IgG1 B1.4 and IgG2a B1.6 were obtained by immunizing BALB/c mice with human bladder cancer cell line EJ-1. In immunohistochemical staining of cryopreserved tissues, B1.4 reacted with 0 of 9 grade 1 TCC, 6 of 11 grade 2, all of 6 grade 3 and five metastatic specimens. The antigen recognized by B1.4 was not expressed by normal urothelial cells but were expressed by vascular endothelial cells and muscle of tunica media. The target antigen of B1.6 was expressed by normal urothelial cells and all grade of TCC. In this study, it was demonstrated that poorly differentiated bladder cancer and metastatic specimens of bladder cancer express a vascular carbohydrate antigen. Taking the escape mechanism of immune surveillance, into consideration, it is possible that the antigen recognized by B1.4 is an indicator of metastatic potential of bladder cancer.

Animals↗

[VM-26 and VP-16 salvage therapy for refractory germinal testicular cancers].

Thirteen evaluable patients with germinal testicular cancers failing to be cured with first-line therapy (refractory) were treated by salvage chemotherapy. Ten patients received salvage chemotherapy with VM-26 (50 mg/m2, twice a week X 6 weeks) and cisplatin (CDDP, 20 mg/m2 for 5 consecutive days every 3 weeks for 3-4 times) (P-VM), 3 patients were also treated by radiation therapy, and 3 patients received VP-16 (100 mg/m2) and CDDP (20 mg/m2) (P-VP), all given daily for 5 consecutive days every 3-4 weeks for 4-5 courses. Of 13 evaluable patients, 6 (46%) had complete response (CR) (three cases were also treated with radiation therapy), 4 (31%) achieved partial response (PR), and 3 (23%) had no response. Limited to 7 patients treated with only P-VM therapy, there were 3 (43%) CR and 4 (57%) PR. Nine patients (69%) remained alive and were continuously disease free 18 to 84 months (median 48 months). Hematologic toxicity was severe, but with no death related to sepsis. Salvage chemotherapy with VM-26 or VP-16 and cisplatin offers potentially curative treatment to patients with refractory testicular cancer. The addition of radiation therapy to salvage chemotherapy was also effective.

Adult↗

Ultrasonography of benign gastric ulcers. Characteristic features and sequential follow-ups.

Ultrasonography was performed for 15 patients with gastric ulcers, after tap water ingestion using 5-MHz and/or 7.5-MHz transducers. Sonographic signs of gastric ulcer were classified as gastric wall edema associated with ulcer crater (six cases) and gastric wall edema only (nine cases). The latter nine included two cases of perforation of gastric ulcers that were depicted as gastric wall edema associated with fluid collection. Ultrasonography proved useful for detecting benign ulcerations and can be used to supplement follow-up examinations, but it cannot replace endoscopy and contrast radiography.

Adult↗

[A case of exohepatic pedunculated hepatocellular carcinoma suspected of adrenal tumor].

A case of exohepatic pedunculated hepatocellular carcinoma that was clinically diagnosed as nonfunctioning adrenal tumor is reported. A 66-year-old man was admitted to our hospital for further examination of unstable angina pectoris. Abdominal echogram and CT scan revealed a large tumor in the right retroperitoneal space. Selective right renal arteriography demonstrated that the tumor was fed by the capsular branch of right renal artery and the right adrenal artery. Adrenal function was normal. Preoperative diagnosis of right nonfunctioning adrenal tumor was made. On operation we found that the tumor was pedunculated from the liver and adhered massively to both right kidney and vena cava. The tumor and right kidney were removed. A histopathological examination demonstrated well differentiated hepatocellular carcinoma (Edmondson's grade II type).

Adrenal Gland Neoplasms↗

[Clinical statistics on inpatients and operations at the Department of Urology, the Center for Adult Diseases, Osaka, 1984-1988].

Statistical observation on inpatients and operations at our department between January 1984 and December 1988 revealed the following results: 1) The total number of inpatients was 1962 (male: 1658, female: 304). The most frequent diseases were bladder cancer (30.0%), benign prostatic hypertrophy (19.2%), prostatic cancer (10.6%) and renal cancer (6.7%). 2) The total number of operations was 1699. The most frequent operations were transurethral resection (TUR) of bladder tumor (22.8%), TUR prostate (20.7%), TUR biopsy (6.5%) and total cystectomy (5.4%).

Female↗

Symptomatic accessory lobe of the liver associated with hyperthyroidism.

A case of symptomatic accessory lobe of the liver occurred in a 15-year-old Japanese girl with hyperthyroidism. The patient presented with acute abdominal distress; at operation, a twisted necrotic mass of the accessory lobe of the liver was found. A review of the literature failed to show a previously reported instance in a child.

Adolescent↗

Immunodetection of estrogen receptor in epithelial and stromal tissues of neonatal mouse uterus.

The tissue distribution and levels of estrogen receptor in neonatal mouse uterine tissue were determined in epithelial and stromal fractions separated by mild enzymatic treatment. Proteins of the isolated fractions were separated by gel electrophoresis and receptor was detected on immunoblots with monoclonal antibody H-222. Estrogen receptor protein was detectable in samples of reproductive tract tissue from 5- and 10-day-old mice. The level of receptor in 5-day-old animals was lower per unit DNA in epithelial cells than in stroma. Receptor levels were increased in both tissue types after treatment with diethylstilbestrol, but not with progesterone. Receptor protein present in these neonatal tissues was able to bind steroid as evidenced by affinity labeling with tamoxifen aziridine. Immunohistochemistry on sections of uteri from 4- and 10-day-old mice confirmed the biochemical results and indicated lower nuclear straining in epithelial cells than in stromal cells of uteri of 4-day-old mice. These results demonstrated that estrogen receptor protein is present in both epithelium and stroma of the neonatal mouse uterus, but at a higher level in stromal cells.

Animals↗