Biomedical subjects

Y Ohe

Publications and source records attributed to Y Ohe.

At least 55 records · Page 3Linked to original sources

PubMed1998

Glutamine is involved in the dependency of brain neuron survival on cell plating density in culture.

The mechanism by which neuronal cell viability in culture is dependent on cell plating density is unclear. To address this question, dissociated cells from the neonatal rat cortex were cultured in a chemically defined medium. Medium conditioned with cortical cells plated at high density (2000 cells/mm2) promoted the survival of neurons grown at low cell density (100 cells/mm2) in a dose-dependent manner. Data obtained from molecular sieving suggested that the molecule(s) promoting the survival of neurons was smaller than 1000 Da. Amino acid analysis of the conditioned medium revealed the release of a mass of glutamine from cortical cells in culture. L-Glutamine mimicked the conditioned medium in action promoting the viability of neurons. These findings suggest that the effect of plating density on neuronal cell viability is mediated at least in part by glutamine released from cultured cells.

Amino Acids↗

PubMed1998

Prostaglandin-D-synthase (beta-trace protein) levels in rat cerebrospinal fluid.

The precise role of prostaglandin-D-synthase (beta-trace protein), the major constituent of cerebrospinal fluid, is unclear. In the present study, a sensitive and highly specific fluoroimmunoassay was developed. The measurement of the enzyme levels in rat CSF revealed a developmental change in the CSF levels with the highest value of 66 +/- 8 microg/ml at 7 days after birth. No significant difference in the levels was seen between different times of day. Subcutaneous injections of all-trans retinoic acid caused a dramatic decrease in the protein levels in a dose- and time-dependent manner. These findings may raise the possibility that prostaglandin-D-synthase in CSF is involved in retinoic acid action on the brain.

Aging↗

PubMed1998

Factors that influence the eligibility of cases for inclusion in clinical trials. The Lung Cancer Chemotherapy Study Group of the Japan Clinical Oncology Group.

BACKGROUND: It is important to minimize the incidence of ineligible cases to improve the quality of clinical trials. To determine factors which may influence the incidence of ineligible cases, the incidence of and reasons for ineligibility in clinical trials were retrospectively analyzed. METHODS: We retrospectively examined the incidence of and reasons for ineligibility for inclusion in eight clinical trials conducted by the Lung Cancer Chemotherapy Study Group of the Japan Clinical Oncology Group and four trials financed by trust funds from a pharmaceutical company. RESULTS: In these 12 clinical studies, the incidence of ineligibility was 4.2% (32/762) (range 0-10.6%). Specific factors that might influence the incidence of ineligible cases were then analyzed. There was a significant difference in the incidence of ineligibility between the methods of registration (P < 0.05). The incidences using a central registration and without using a central registration system were 2.8% (9/322) and 5.2% (23/440) respectively. We also analyzed ineligible cases in clinical studies published in the Journal of Clinical Oncology. In clinical studies published in the Journal of Clinical Oncology recently and 10 years ago, the incidences of ineligible cases were 5.0% (942/18 878) and 4.1% (206/4995) respectively. In clinical studies on lung cancer published in the Journal of Clinical Oncology from 1984 to 1995, the incidence of ineligible cases was 4.7% (900/19,116). There was no significant difference in the incidence of ineligible cases between our 12 studies and the Journal of Clinical Oncology clinical studies by the chi 2 test (P > 0.05). CONCLUSIONS: We conclude that the incidence of ineligible cases in our studies is similar to that in clinical trials published in the Journal of Clinical Oncology. Central registration systems are useful for checking for ineligibility, and to increase the quality of clinical trials.

Clinical Trials as Topic↗

PubMed1998

[Clinical trial of IL-12 for cancer patients].

Interleukin-12 (IL-12) is a cytokine that stimulates T cells and NK cells. It induces interferon-gamma and plays a unique role in promoting type 1 T helper cell responses. In various animal models, IL-12 has shown a therapeutic effect controlling growth of primary and metastatic tumors at nontoxic doses. On the basis of these findings, IL-12 is now under clinical trial. Fever, flu-like, general fatigue, arthralgia, myalgia, leukopenia, liver dysfunction and so on are the reported toxicities of IL-12. A dramatic decrease of IL-12 AUC after consecutive dosing of IL-12, production of IL-10 and temporal elevation of NK and LAK activities after IL-12 administration have also been observed. Several patients achieve PRs after the administration, but dramatic clinical responses have never been reported. Intensive research on the mechanisms of antitumor response of IL-12 in cancer patients should be very important to the successful development of IL-12 as an anti-cancer agent.

Clinical Trials as Topic↗

PubMed1997

Genetic immunotherapy by intrapleural, intraperitoneal and subcutaneous injection of IL-2 gene-modified Lewis lung carcinoma cells.

The induction and augmentation of tumor non-specific immunity and of tumor-specific immunity by intrapleural, intraperitoneal and subcutaneous injection of interleukin-2 (IL-2) gene-modified Lewis lung carcinoma (LLC) cells (LLC-IL2) was tested in C57BL/6 mice. Intrapleural injection of LLC cells induced lung tumors with a malignant effusion, intraperitoneal injection induced peritoneal tumors with ascites and subcutaneous injection induced subcutaneous tumors. Intrapleural injection of irradiated LLC-IL2 cured pre-existing lung LLC tumors and extended the survival of the mice but did not affect survival of mice with pre-existing peritoneal tumors nor did it affect the growth of s.c. tumors. Intraperitoneal injection of irradiated LLC-IL2 cured pre-existing LLC peritoneal tumors and extended the survival of the mice but did not affect survival of mice bearing lung tumors nor did it affect the growth of s.c. tumors. Subcutaneous injection of irradiated LLC-IL2 did not affect the growth of preexisting s.c. tumors and also did not improve survival of mice bearing the lung or peritoneal tumors. Injection with irradiated LLC-IL2 by all routes, i.e., intrapleural, intraperitoneal and s.c., protected against subsequent re-challenge with LLC. Eight days after the initial immunization (early stage of immunization), non-adherent mononuclear cells in the peritoneal cavity of the mice treated with intraperitoneal injection of irradiated LLC-IL2 displayed enhanced cytotoxicity against LLC, B16-F10 and P815 cells, while the cytotoxic activity of spleen cells in the same mice did not change. The efficiency of induction of tumor-specific immunity was the strongest after intraperitoneal immunization and weakest after s.c. immunization. In vitro analysis using the spleen cells of mice immunized with irradiated LLC-IL2 suggested that CD8+ T cells play a key role in tumor-specific immunity.

Animals↗

PubMed1997

Phase I study of sequentially administered topoisomerase I inhibitor (irinotecan) and topoisomerase II inhibitor (etoposide) for metastatic non-small-cell lung cancer.

We conducted a phase I study of irinotecan (CPT-11) and etoposide (VP-16) given sequentially to untreated patients with metastatic non-small-cell lung cancer. Arm A: CPT-11 was given over 90 min on days 1-3 and VP-16 was given over 60 min on days 4-6. Arm B: VP-16 was given on days 1-3 and CPT-11 on days 4-6. G-CSF was given to all patients daily on days 7-17. Twenty-seven patients were entered randomly at the two arms. The major dose-limiting toxicities in arms A and B were granulocytopenia and diarrhoea. Transient elevations of transaminases and bilirubin were observed in both arms. The degree of the toxicities did not differ between the two arms. The maximum tolerated doses (MTDs) were 60 mg m-2 CPT-11 and 60 mg m-2 VP-16 in both arms. Of the 13 patients who received more than two cycles, two out of five achieved partial response (PR) at the first level of arm A and one out of four achieved PR at the second level of arm B. We conclude that these schedules of sequential CPT-11 and VP-16 administration were inappropriate because of severe toxicities.

Adult↗

PubMed1997

Changes in distribution of cystatin C, apolipoprotein E and ferritin in rat hypothalamus after hypophysectomy.

To clarify the mechanism underlying the process of degeneration of injured CNS neurons, we have immunohistochemically examined the distribution of cystatin C, apolipoprotein E, IgG, transferrin and ferritin in the hypophysectomized rat hypothalamus. Stainings for ferritin revealed that reactive microglial cells massed in the paraventricular and supraoptic nuclei 14 days after hypophysectomy, when the degeneration of vasopressin neuronal cell bodies was apparent. Cystatin C-positive magnocellular neurons first appeared at 4 days and the number of intensely-stained cells increased rapidly up to the 7th day of hypophysectomy, followed by a decrease thereafter. Most of such cystatin C-positive neurons were simultaneously stained with anti-vasopressin serum. Accumulation of apolipoprotein E in extracellular spaces was obvious in the both hypothalamic magnocellular nuclei at 7 days. Several apolipoprotein E-positive cells were localized in the supraoptic nucleus, although the number of apolipoprotein E-positive cells was much smaller than that of cystatin C-positive cells. The experiments performed with the transferrin and IgG antibodies showed undetectable levels of such molecules in and around the degenerating magnocellular neurons during whole experimental periods. These findings suggest the importance of cystatin C and apolipoprotein E in the process of degeneration and/or regeneration of magnocellular neurons after hypophysectomy.

Animals↗

PubMed1997

Interferon-gamma-inducing factor gene transfection into Lewis lung carcinoma cells reduces tumorigenicity in vivo.

To investigate the immunoregulatory effect of murine interferon-gamma-inducing factor (mIGIF), we transfected Lewis lung carcinoma (LLC) cells with a mammalian expression vector containing the mIGIF complementary DNA. The culture medium of the transfectant cells stimulated interferon-gamma (IFN-gamma) production by spleen cells in vitro in the presence of anti-CD3 antibody and markedly potentiated the effect of interleukin-12 (IL-12) on IFN-gamma production by spleen cells. mIGIF transfectant cells showed reduction of tumorigenicity and induction of an in vivo immuno-protective effect against the parental LLC cells. To examine the combined effect of systemic administration of recombinant IL-12 (rIL-12) and local mIGIF on the tumorigenicity, mice were challenged with LLC or transfectant cells on day 0, and the tumor-bearing mice were injected with 50 ng of rIL-12 intraperitoneally from day 7 to 11. Systemic rIL-12 showed an anti-tumor effect. However, mIGIF gene expression did not potentiate this effect of systemic rIL-12 in vivo.

Animals↗

PubMed1997

[Importance of instructing anesthesiologists in handwashing against bacterial contamination].

The importance of handwashing in preventing the spread of nosocomial infection has been stressed. Using a modified glove juice method, we have already shown the efficacy of washing of anesthesiologists' hands with alcohol based antiseptic solutions against bacterial contamination. The efficacy of handwashing, however, varied because many anesthesiologists washed only the palm and the back. In the present study, we instructed them to wash their hands using rubbing method, from finger tip to the wrist until drying the solutions completely. We compared the efficacy of handwashing, by decrease of bacteria counts after general anesthesia, between the instructed method and the customary way which was done ordinarily in the ward. The instructed method was more effective on the decrease of bacteria counts than the customary way. In the instructed method, the efficacy of handwashing was not different between the antiseptic solutions. In conclusion, doctors not only should practice handwashing with the antiseptic solutions after each contact with the patient, but also wash their hands from the finger tip to the wrist until they become completely dry.

Anesthesia, General↗

PubMed1997

[Prophylactic cranial irradiation in small cell lung cancer].

The Brain is one of the common relapse sites in small cell lung cancer because of isolation from chemotherapeutic agents by the blood-brain barrier. Prophylactic cranial irradiation (PCI) is expected to reduce brain relapse and increase the survival rate. PCI prolonged the survival in only 10-20% of patients with small cell lung cancer after complete response. Most randomized trials demonstrated the significant reduction of brain relapse, however, none of them demonstrated an increase of survival rate because their sample sizes were relatively small to detect the difference of survival, such as 10% in 3-year survival. The results of ongoing meta-analysis should provide new findings on the survival benefits of PCI. No standard PCI dose and schedule are established, however, over 30Gy for total dose, over 3Gy per fraction. Concurrent use with chemotherapy is considered to induce central nerve toxicity. PCI should be proposed for patients with complete response as an optional treatment.

Brain Neoplasms↗

PubMed1997

Serum levels of pro-gastrin-releasing peptide for follow-up of patients with small cell lung cancer.

To assess the clinical usefulness of serum pro-gastrin-releasing peptide (Pro-GRP) as a tumor marker for small cell lung carcinoma (SCLC), we measured serum levels of Pro-GRP with a newly developed ELISA and measured serum levels of neuron-specific enolase (NSE) in 44 patients with untreated SCLC and 77 patients with untreated non-SCLC. We prospectively measured serum levels of Pro-GRP and NSE in SCLC patients after initial treatment until relapse. The sensitivity (70%) and specificity (91%) of Pro-GRP were similar to those of NSE (70 and 86%). Thirty-nine % of patients who had a partial response still had elevated serum levels of Pro-GRP at the time of restaging after initial treatment. In follow-up study, 94% of patients had elevated serum levels of Pro-GRP again at the time of relapse, whereas 37% of patients showed elevated levels of NSE. Levels of Pro-GRP increased a median of 35 (-95 to 151) days before clinical evidence of relapse was detected with successive physical examinations and imaging studies, whereas levels of NSE increased 20 (-85 to 124) days after relapse was detected (P < 0.05). Pro-GRP was helpful as a diagnostic aid and a marker for therapeutic effect and relapse in patients with SCLC, supplemented to serum NSE.

Adult↗

PubMed1996

Accumulation of apolipoprotein E and beta-amyloid-like protein in a trace of the hippocampal CA1 pyramidal cell layer after ischaemic delayed neuronal death.

We found that apolipoprotein E (apo E) accumulates in a trace of the hippocampal CA1 pyramidal cell layer within 6 months after 5 min ischaemia. Intense methenamine-silver (M-S) stainings were seen in the entire CA1 subfield 3 months after ischaemia. The M-S staining pattern may imply the appearance of soluble A beta-like proteins. The apo E-positive trace was also positively stained with anti-beta-amyloid (A beta) protein antibodies, but not with anti-beta-amyloid protein precursor (APP) antibodies. These results suggest that A beta-like protein accumulates in ischaemic brain after neuronal cell death. Adjacent reactive astrocytes showed both apo E- and A beta-immunoreactivities. These astrocytes may be involved in the clearance of apo E- and A beta-positive material. We presume that the coincident distribution pattern for apo E- and A beta-immunoreactivity implies formation of the insoluble and stable A beta-apo E complex which is known to exist in the brain of individuals with Alzheimer's disease. The ischaemic model may be useful in studying apo E and A beta deposition in the brain.

Amyloid beta-Peptides↗

PubMed1996

Hypersensitivity of NIH3T3 cells transformed by H-ras gene to DNA-topoisomerase-I inhibitors.

We examined the effects of the introduction of H-ras oncogene into murine cell line NIH3T3 on growth inhibition by topoisomerase-I (topo-I) inhibitors. The H-ras-transformed cells (pT22-3) showed approximately 12-fold increased sensitivity to a novel topo-I inhibitor, NB-506 [6-N-formylamino-12,13-dihydro-1,11-dihydroxy-13-(beta-D-glucopyranosyl) -5H-indolo(2,3-a)pyrrolo(3,4-c) carbazole-5,7(6H)-dione], compared with the parental NIH3T3 cells. pT22-3 also showed increased sensitivity to other topo-I inhibitors such as camptothecin (approx. 3.0-fold) and CPT-11 (irinotecan, approx. 3.0-fold). Transformation of NIH3T3 by another oncogene (erbB2) did not affect their sensitivity to these topo-I inhibitors. pT22-3 had approximately 32-fold higher topo-I activity than NIH3T3, but the same topo-I content. In a cell-free system, topo-I activity was increased 2-fold by addition of the H-ras protein precipitated from pT22-3 cells. Topo I in the nuclear extract of pT22-3 was eluted easily by low concentrations of NaCl compared with that of NIH3T3, suggesting a qualitative change in pT22-3 topo 1. Increased phosphorylation of topo I was observed in pT22-3. Furthermore, NB-506 decreased the amount of the GTP-bound form of the H-ras product in pT22-3 cells. These results suggest that the high growth-inhibitory effect of a topo-I inhibitor, NB-506, on H-ras-transformed NIH3T3 cells is due to the H-ras-mediated signal-transduction pathway.

3T3 Cells↗

PubMed1996

Diazepam binding inhibitor is a potent cholecystokinin-releasing peptide in the intestine.

Pancreatic proteases in the duodenum inhibit the release of cholecystokinin (CCK) and thus exert feedback control of pancreatic exocrine secretion. Exclusion of proteases from the duodenum either by the diversion of bile-pancreatic juice or by the addition of protease inhibitors stimulates exocrine pancreatic secretion. The mechanism by which pancreatic proteases in the duodenum regulate CCK secretion is unknown. In this study, we isolated a trypsin-sensitive peptide that is secreted intraduodenally, releases CCK, and stimulates pancreatic enzyme secretion in rats. This peptide was found to be identical to the porcine diazepam binding inhibitor by peptide sequencing and mass spectrometry analysis. Intraduodenal infusion of 200 ng of synthetic porcine diazepam binding inhibitor1-86 in rats significantly stimulated pancreatic amylase output. Infusion of the CCK antagonist MK-329 completely blocked the diazepam binding inhibitor-stimulated amylase secretion. Similarly, diazepam binding inhibitor33-52 [corrected] also stimulated CCK release and pancreatic secretion in a dose-dependent manner although it was 100 times less potent than the whole peptide. Using a perfusion system containing isolated mucosal cells from the proximal intestine of rats, porcine diazepam binding inhibitor 10(-12) M) dose dependently stimulated CCK secretion. In separate studies, it was demonstrated that luminal secretion of the diazepam binding inhibitor immunoreactivity (7.5 X 10(11) M) could be detected in rat's intestinal washing following the diversion of bile-pancreatic juice. The secretion of this peptide was inhibited by atropine. In conclusion, we have isolated and characterized a CCK-releasing peptide that has a sequence identical to the porcine diazepam binding inhibitor from pig intestinal mucosa and that stimulates CCK release when administered intraduodenally in rat. This peptide may mediate feedback regulation of pancreatic enzyme secretion.

Amino Acid Sequence↗

PubMed1996

Activation of iron handling system within the gerbil hippocampus after cerebral ischemia.

Analyzing the distribution pattern of transferrin (Tf) and ferritin, we investigated the changes in iron metabolism related proteins in the process of neuronal death induced by 5 min ischemia. In the control animals, Tf immunoreactivity was localized in the oligodendrocytes. Ferritin was distributed in both neurons and gliacytes, particularly microglia. In parallel with the delayed neuronal death, Tf-positive atrophied neurons and numerous ferritin-positive gliacytes appeared in the CA1 subfield of the hippocampus 4 days after ischemia, when glia fibrillary acidic protein (GFAP)-positive astrocytes also appeared throughout the hippocampal structure. A considerable number of ferritin-positive phagocytes (reactive microglia) appeared in the stratum pyramidale from the seventh day. Our data show clearly that the mobilization of Tf and ferritin-positive phagocytes are linked with the degeneration of neurons induced by cerebral ischemia. These events may suggest an activation of iron handling system under the postischemic condition.

Animals↗

PubMed1996

Cystatin C and apolipoprotein E immunoreactivities in CA1 neurons in ischemic gerbil hippocampus.

The distribution patterns of cystatin C and apolipoprotein E (apo E) were studied immunocytochemically in the gerbil hippocampus before and after 5 min ischemia. In the controls, cystatin C was distributed mainly in astrocytes. In addition, a large number of dots positive for cystatin C were observed around the outlines of neuronal perikarya in the CA1 subfields. One day after ischemia, cystatin C-positive stainings outlining neuronal cell bodies disappeared. On the fourth day, intense stainings for cystatin C appeared in atrophied pyramidal neurons and these stainings in neurons disappeared by the 14th day. A remarkable increase in the number of cystatin C-positive astrocytes occurred on the fourth day and thereafter these spread over the whole of the CA1 subfield. Apo E was also distributed in astrocytes in the control specimens. From the fourth day, extra- and/or intracellular distribution of apo E-immunoreactivities was noted in the stratum pyramidale. Apo E-positive astrocytes disappeared transiently on the fourth day and then reappeared and increased remarkably by the 14th day. These findings indicate that cystatin C and apo E are involved in the degeneration process of brain neuronal cells.

Animals↗

PubMed1996

Improvement by eicosanoids in cancer cachexia induced by LLC-IL6 transplantation.

Cachexia frequently occurs in the late stages of cancer, and is difficult to manage. We previously reported that interleukin-6 (IL-6) cDNA transfection into Lewis lung carcinoma (LLC-IL6) induced cachexia-like symptoms in C57BL/6 mice. This was thought to be a useful experimental model of cancer cachexia. We have examined the effects of two eicosanoids, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), in order to evaluate whether they could relieve cachexia. LLC-IL6-bearing animals were divided into three treatment groups receiving DHA, EPA or water as the control; 80-microliter samples of these compounds (purity > 95%) were administered orally by catheter daily starting 7 days after tumor transplantation. Tumor growth curves were similar in the three groups. There were no differences in water or food intake in the three groups. However, body weight, a marker of cachexia, was significantly higher in treated mice than in the control group. Sixteen days after tumor transplantation, the mean body weight was 17.45 g (P < 0.05), 17.2 g and 16.41 g in the groups receiving DHA, EPA and water respectively. The eicosanoids did not affect serum levels of IL-6. Ubiquitination of muscle protein, a marker of proteolysis coupled to cachexia, was compared in LLC-IL6- and LLC-transplanted mice. The eicosanoids prevented the ubiquitination of approximately 180 kDa protein. These results suggest that eicosanoids may prevent the cachexia mediated by IL-6.

Animals↗

PubMed1996

Expression of CD10/neutral endopeptidase in normal and malignant tissues of the human stomach and colon.

The expression of common acute lymphoblastic leukemia antigen (CALLA; CD10), which is identical to neutral endopeptidase (NEP, EC3.424.11), was examined in the malignant and adjacent noninvaded tissues of the human stomach and colon (n = 27). All of 27 normal and 18 well or moderately differentiated adenocarcioma tissue specimens were positive for monoclonal antibody (mAb) NL-1 against CD10/NEP, whereas the expression level was clearly decreased in all of 9 specimens of poorly differentiated adenocarcinoma. In addition, all of 7 gastric or colorectal carcinoma cell lines tested showed decreased expression of CD10/NEP. Sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analysis of the crude antigen J5 from the normal colon tissue lysate by mAb J5 detected a single band of approximately 100 kDa that was consistent with that of NALM-6 cells used as a positive control. These findings suggest that CD10/NEP is expressed in normal epithelial cells of the human stomach and colon, whereas the expression level is decreased in the poorly differentiated type of adenocarcinoma.

Adenocarcinoma↗