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Biomedical subjects

T Oishi

Publications and source records attributed to T Oishi.

At least 55 records · Page 3Linked to original sources

Differentiation of pinopsin-immunoreactive cells in the developing quail pineal organ: an in-vivo and in-vitro immunohistochemical study.

The avian pineal organ contains several types of photoreceptors with different photopigments: rhodopsin, iodopsin, and pinopsin. We have previously examined the differentiation of both rhodopsin-like and iodopsin-like immunoreactive cells during pineal development in quail embryos to determine the onset of synthesis of specific proteins and their cellular localization. In the present study, we have performed pinopsin immunohistochemistry on in-vivo developing and in-vitro cultured pineal organs of quail embryos. The results were compared with those obtained with rhodopsin and iodopsin immunohistochemistry. In the developing pineal organs, pinopsin immunoreactivity was detected at embryonic day 8, i.e. five days earlier than rhodopsin-like and iodopsin-like immunoreactivities. It was localized exclusively in the protrusions extending into the lumen throughout development, whereas rhodopsin-like and iodopsin-like immunoreactivities were usually found both in cell bodies and processes. These differences were also observed under two different types of culture conditions (dissociated cell culture and organ culture) indicating that, in the avian pineal organ, the expression pattern of the pinopsin gene is basically different from those of the other two pineal photopigments. The present study suggests that pineal cells have a mechanism for the polarized transport of pinopsin molecules.

Animals↗

Quantitative non-radioactive in situ hybridization study of GAP-43 and SCG10 mRNAs in the cerebral cortex of adult and infant macaque monkeys.

We performed non-radioactive in situ hybridization histochemistry in several areas that include both the association areas and the lower sensory areas of monkey cerebral cortex, and investigated the localization of neurons expressing two growth-associated proteins: GAP-43 and SCG10. Both GAP-43 and SCG10 mRNAs were observed in both pyramidal and non-pyramidal neurons. Prominent hybridization signals for GAP-43 mRNA were observed in layers II-VI of the adult association areas: the prefrontal areas (FD), the temporal (TE) and the parietal (PG) association areas. The signals for GAP-43 mRNA were weak in layers I-III of the adult primary somatosensory area (PB) and primary (OC) and secondary (OB) visual areas, and cells with prominent signals were observed in layers IV-VI. The prominent signals for SCG10 mRNA were observed in layers IV-VI of all areas examined. These results suggest that the expression pattern of GAP-43 mRNA, but not that of SCG10 mRNA, may be related to the functional difference between association and lower sensory areas of adult cortex. In the infant cortex (postnatal days 2, 8 and 31), the signals for both mRNAs were intense in layers II-VI of all areas. Therefore, layer-specific expressions of GAP-43 and SCG10 mRNAs are established after the first postnatal month.

Aging↗

Treatment with a Ca(2+) channel blocker, barnidipine, reduces platelet-derived growth factor B-chain mRNA in glomeruli of spontaneously hypertensive rats.

We investigated the effect of barnidipine hydrochloride, a Ca(2+) channel blocker, on the glomerular level of mRNA expression of platelet-derived growth factor (PDGF) B-chain and transforming growth factor (TGF)-beta(1) in spontaneously hypertensive rats (SHR) with reverse transcription and polymerase chain reaction. Thirteen-week-old SHR were provided with food containing barnidipine (0.6 mg/g of food, average dose during treatment: 53 mg/kg of body mass/day) for 3 weeks. A stable reduction in systolic blood pressure relative to that of age-matched control SHR was recorded after week 1 of therapy. Although no renal histological changes were observed after 3 weeks of treatment with barnidipine, the level of expression of PDGF B-chain mRNA in glomeruli was significantly reduced relative to that in control SHR. The glomerular level of TGF-beta(1) mRNA expression was not affected by the treatment. Treatment with barnidipine significantly reduced the excretion of urinary protein. Thus, the stable reduction in systemic blood pressure by barnidipine is associated with a reduction in PDGF B-chain mRNA expression in the glomerulus and reduction in urinary protein excretion in SHR.

Animals↗

Development of GAP-43 mRNA in the macaque cerebral cortex.

To estimate the extent of axonal growth in various areas of the cerebral cortex, we measured the amount of GAP-43 mRNA in the cerebral cortex of developing macaque monkeys. In four areas, i.e., the prefrontal area (FD delta), the temporal association area (TE), the primary somatosensory area (PC), and the primary visual area (OC), the amount of GAP-43 mRNA was measured from the intermediate fetal period [embryonic day 120 (E120)] to the adult stage. In two other areas, i.e., the parietal association area (PG) and the secondary visual area (OB), the amount of GAP-43 mRNA was measured during the postnatal period. The amount of GAP-43 mRNA was highest at E120, decreased roughly exponentially, and approached the asymptote by postnatal day 70 (P70). The amount of GAP-43 mRNA was higher in the association areas (FD delta, TE, and PG) than in the primary sensory areas (PC and OC) during development and at the adult stage. These findings suggest that axonal growth in the cerebral cortex is most exuberant before or during the intermediate fetal period and approximately ends by P70. Furthermore, axonal growth is evidently more intensive in the association areas than in the primary sensory areas during the stage following the intermediate fetal period.

Aging↗

Effect of continuous infusion of vasopressin on glomerular growth response in spontaneously hypertensive rats.

Vasopressin (VP) is thought to play an important role in the pressor and proliferative responses of renal glomeruli. We have utilized the spontaneously hypertensive rat (SHR) model to determine if glomerular proliferation is induced by chronic infusion of exogenous VP. SHR were continuously infused with 0.1 ng/kg/min VP (H-VP group), 1.0 ng/kg/min (H-VP group), or vehicle alone (control group) for fifteen days using osmotic minipumps, and the histological alterations and level of expression of platelet-derived growth factor B-chain (PDGF-B) and transforming growth factor (TGF)-beta1 mRNA were determined. We observed no significant differences in systolic blood pressure, heart rate, serum electrolytes, protein and creatinine among the three groups of rats, but urine volume was found to be significantly decreased, and urine osmolality significantly increased, in the H-VP group. Kidney weight was significantly higher in the H-VP and L-VP groups than in the control group, and glomerular diameter was higher in the H-VP group. When we measured mesangial injury score and cellularity in the glomeruli of these animals, we observed VP dose-dependent proliferative changes. In the immunofluorescence study, although we did not find an obvious difference in depositions of collagen types III, IV and VI, alpha-smooth muscle actin and PDGF-B among the groups, the collagen type I and TGF-beta1 increased in several glomeruli in the H-VP group. Reverse transcription polymerase chain reaction (RT-PCR) revealed no significant differences in the glomerular levels of PDGF-B mRNA among the three groups of rats, but the level of expression of TGF-beta1 mRNA was significantly higher in the L-VP and H-VP groups than in the control group. These findings suggest that VP may contribute to glomerular proliferation, and that VP may exert its effects in part through the induction of TGF-beta1 expression. These results also raise the possibility that blockade of VP receptors may be useful in the treatment of some forms of glomerular disease.

Animals↗

A deep brain photoreceptive molecule in the toad hypothalamus.

We have isolated a cDNA clone encoding a deep brain photoreceptive molecule from the hypothalamic cDNA library of the toad, Bufo japonicus. The deduced amino acid sequence showed the highest similarity to that of pinopsin (75-76%) among vertebrate retinal opsins, indicating the expression of toad pinopsin in the deep brain. Antibodies raised against the C-terminal tail of toad pinopsin stained cell bodies and the knob-like structures of the cerebrospinal fluid-contacting neurons in the anterior preoptic nucleus. This region is known to play an important role in breeding behavior, suggesting that toad pinopsin acts as a photosensor for the photoperiodic gonadal response.

Amino Acid Sequence↗

Glutathione concentration may be a useful predictor of response to second-line chemotherapy in patients with ovarian cancer.

BACKGROUND: No useful predictor of resistance or sensitivity to second-line chemotherapy is known for ovarian cancer. The objective of this prospective study was to determine the utility of tumor glutathione S-transferase-pi (GST-pi) expression or glutathione (GSH) concentration in predicting ovarian cancer patients' responses to second-line chemotherapy. METHODS: Tumor samples were obtained from 26 patients with relapsed epithelial ovarian cancer 3-4 weeks before the initiation of second-line chemotherapy with etoposide (daily on Days 1-5) and cisplatin (on Day 5). The expression of GST-pi in tumor samples was determined by immunohistochemical staining and Western blot analysis. GSH concentration was measured by an enzymatic assay. RESULTS: The response rate was 38.4%. The estimated 3-year survival rate for the responders (66.7%) significantly exceeded that for the nonresponders (9.1%). Expression of GST-pi by immunohistochemical staining was more frequently observed in nonresponders (2 of 10 responders vs. 11 of 16 nonresponders). Western blot analysis detected GST-pi in all cases. There was no significant difference in the relative density values of the GST-pi Western blot analysis between the two groups. The mean value of GSH concentration in nonresponders was significantly higher than in responders (18.4 +/- 9.7 vs. 7.5 +/- 8.2 microg/mg protein). GSH concentration was below the cutoff point (10.3 microg/mg protein) in all responders except one. CONCLUSIONS: Second-line chemotherapy consisting of etoposide and cisplatin is effective in the treatment of relapsed epithelial ovarian cancer. In addition, tumor concentration of GSH may be a useful predictor of the response to this therapy.

Adult↗

Gene expression of growth-associated proteins, GAP-43 and SCG10, in the hippocampal formation of the macaque monkey: nonradioactive in situ hybridization study.

We performed nonradioactive in situ hybridization histochemistry in the monkey hippocampal formation that includes the hippocampus, the subicular complex, and the entorhinal cortex to detect the expression of mRNA for two growth-associated proteins: GAP-43 and SCG10. Overall, the distribution patterns overlapped but were partially distinct. In the hippocampus, the intense hybridization signals for both GAP-43 and SCG10 mRNAs were observed in the pyramidal cell layer of Ammon's horn, especially in CA3 subfields. The intense hybridization signals were also observed in the stratum oriens of Ammon's horn and the polymorphic layer of the dentate gyrus. In the granule cell layer of the dentate gyrus, many GAP-43 mRNA-positive cells were observed, whereas a few positive cells with weak signals were observed for SCG10 mRNA. Throughout the subicular complex, the hybridization signals for both mRNAs were weak. In the entorhinal cortex, both mRNAs were abundant in the caudal field. These subregion-specific expression of the growth-associated proteins may reflect the functional specialization regarding plasticity in each region of the monkey hippocampal formation.

Animals↗

Indication and efficacy of radiation therapy following radical surgery in patients with stage IB to IIB cervical cancer.

OBJECTIVE: To determine the role of radiation therapy following radical surgery in patients with cervical cancer. METHOD: A total of 104 patients with International Federation of Gynecology and Obstetrics stage IB to IIB cervical cancer who underwent radical hysterectomy and pelvic lymph node dissection at Tottori University Hospital between 1988 and 1994 were entered in this study. The criteria for postoperative radiotherapy included positive lymph node involvement, compromised surgical margin, parametrial extension, or deep stromal invasion of cervix with less than 3 mm of distance from serosa. Postoperative radiotherapy consisted of 10-20 Gy whole pelvis and an additional parametrial dose with a midline block to deliver a total of 44-50 Gy to the pelvic side wall. RESULTS: Sixty-two patients (59.6%) who met the criteria received postoperative radiotherapy. Lymph node metastasis was most frequent in stage IIB followed by stage IIA and then stage IB (36.7, 22.2, and 10.7%, respectively). Parametrial extension was observed 8.7% of patients with stage IB and 27.7% of those with stage IIA. The estimated 5-year survival rate for patients undergoing surgery alone was 97.6% and that for patients receiving postoperative radiotherapy was 82.7% (P = 0.038). Multivariate analysis showed that lymph node metastasis and parametrial extension were major prognostic factor, but the survival rate did not relate to depth of stromal invasion. CONCLUSION: Postoperative radiotherapy may improve the survival of patients with cervical cancer exhibiting lymph node metastasis or parametrial extension.

Adult↗

Alteration of telomerase activity associated with development and extension of epithelial ovarian cancer.

OBJECTIVE: To assess telomerase activity associated with the development and extension of epithelial ovarian cancer and to investigate the relationship between p53 gene status and telomerase activity. METHODS: A total of 53 samples (41 epithelial ovarian cancers, five borderline epithelial tumors, four benign adenomas, and three surface epithelia) were examined for telomerase activity by the polymerase chain reaction (PCR) -based telomeric repeat amplification protocol assay. Mutations in the p53 gene were determined by PCR-single strand conformation polymorphism analysis. RESULTS: Telomerase activity was detected in 33 of 41 epithelial ovarian cancers and in three of five borderline malignancies but was not detectable in either benign tumors or normal surface epithelium. The mean (+/-standard deviation [SD]) intensity of telomerase activity in cancers was significantly higher than that in borderline malignancies (10.6+/-8.2 versus 3.6 4+/-1.3). The positivity of telomerase activity did not correlate with any clinical findings, but the intensity (+/-SD) of telomerase activity was significantly higher in tumors with lymph node involvement (12.2+/-8.3 versus 3.8+/-1.1). Mutations of the p53 gene were observed in 44% of ovarian cancers; p53 gene status did not relate to telomerase activity. Multivariate analysis showed that the intensity of telomerase activity was not an independent factor for prognosis of patients with ovarian cancer. CONCLUSION: Telomerase activity may be associated with development and extension of epithelial ovarian cancer.

Adenocarcinoma, Mucinous↗

A newly developed adenovirus-mediated transfer of a wild-type p53 gene increases sensitivity to cis-diamminedichloroplatinum (II) in p53-deleted ovarian cancer cells.

A new recombinant adenovirus carrying a wild-type p53 gene (AxCAp53) was developed and the combination effect of p53 gene transfer and cis-diamminedichloroplatinum (II) (CDDP) was examined in an ovarian cancer cell line, SK-OV-3, with deletion of the p53 gene. AxCAp53 showed a high efficiency of gene transduction and increased sensitivity to CDDP in the SK-OV-3 cells. It was found that the sensitivity of the cells to CDDP correlated with the amount of infectious units of virus per cell of AxCAp53 which correlated with p53 protein expression. The results suggest that the combination of CDDP and AxCAp53 may be a potential strategy for the therapy of CDDP-resistant ovarian cancer.

Adenocarcinoma↗

An evaluation of infants' growth in the Kingdom of Nepal.

BACKGROUND: The His Majesty's Government/Japan International Cooperation Agency Primary Health Care Project began in April 1993 in collaboration with the Saitama Prefectural Government, for the purpose of improving the health status of the people in model districts of the Kingdom of Nepal. Growth monitoring is one of the basic methods that defines the health and nutritional status of children. METHODS: Anthropometric indices were measured in 759 children in the Bhaktapur district. We used the World Health Organization prototype growth chart and national growth standard for Japanese children (1990) to analyze the growth data. RESULTS: We found that the average bodyweight growth curve of children up to 4 months of age followed the 50th percentile reference curve. For children of 5-12 months of age, there was a delay in bodyweight gain and the growth curve reached the 3rd percentile curve. For children more than 1 year old, the growth curve moved below the third percentile curve. Catch-up growth did not occur before the children reached 5 years of age. The main causes of catch-up growth being hampered were chronic undernutrition and inadequate nutritional balance. CONCLUSIONS: As this was the first opportunity to evaluate infant growth in this district, the first important consequence of the results was to analyze the causes of growth faltering and failure-to-thrive in Nepalese children. Even more important, was the need to give appropriate counseling on improving feeding and other health-related practices, and the most important consequence of all was to instruct Nepalese health workers that utilizing the growth charts is an integral part of health care.

Anthropometry↗

[Twelve cases of systemic lupus erythematosus in boys].

We compared clinical findings in 12 cases of systemic lupus erythematosus (SLE) in boys with those in 49 cases in girls. The age at which SLE developed in boys was consistent with that of infantile SLE and there was no age specificity. Momy cases in boys were diagnosed earlier as compared with cases in girls. Symptoms of infantile SLE, such as fever, arthalgia, butterfly rash, and urinary abnormalities, did not differ between boys and girls. However, a higher percentage of boys (58.3%) had central nervous system complications at onset than did girls (30.6%). Platelet counts tended to be higher in boys than in girls, a finding that suggests SLE tends to be more severe in boys than in girls. The incidence in the appiarance of LE cells, anti-Sm antibodies and immune complexes was higher in boys than in girls. Type IV or V renal pathologic changes (World Health Organization Histologic Classification) were present in 70% of boys. Our findings suggest that SLE in boys is more severe than that in girls and is more likely to be associated with central nervous system complications and severe renal complications.

Adolescent↗

Effects of OPC-21268, a vasopressin V1-receptor antagonist, on expression of growth factors from glomeruli in spontaneously hypertensive rats.

To assess the chronic in vivo effects of OPC-21268, a vasopressin-V1 receptor antagonist, on renal injury, we investigated the mRNA expressions of platelet-derived growth factor (PDGF) B-chain, transforming growth factor (TGF)-beta1 and proliferating cell nuclear antigen (PCNA) in the glomeruli of spontaneously hypertensive rats (SHR) treated with OPC-21268 for 3 weeks. SHR aged 10 weeks were given 2% NaCl in drinking water for 3 weeks. The OPC group was fed a 0.5% OPC-21268-containing diet for 3 weeks and the control group was given a normal diet. There were no significant changes in the time course of systolic blood pressure, heart rate, urine volume, or urinary sodium, protein and N-acetyl-beta-glucosaminidase (NAG) excretion between the two groups. Serum electrolytes, protein and creatinine levels also did not differ between the groups. The mRNA expressions of PDGF B-chain, TGF-beta1 and PCNA in the glomerulus were examined using reverse transcriptase-polymerase chain reaction (RT-PCR) methods. The mRNA expressions of PDGF B-chain and PCNA among these were significantly suppressed in the OPC group. No significant differences in renal histology including the organ weights were found between the two groups; however, the glomerular size tended to be enlarged in the OPC group. These findings suggest that chronic V1-receptor blockade directly inhibits the glomerular proliferative injury of salt-loaded SHR at the established hypertension stage.

Acetylglucosaminidase↗