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Biomedical subjects

T Isobe

Publications and source records attributed to T Isobe.

At least 73 records · Page 4Linked to original sources
PubMed2000

Cyclosporin A, but not bursectomy, abolishes the protective immunity of chickens against Leucocytozoon caulleryi.

Chickens that survive primary infection with Leucocytozoon caulleryi show strong resistance to reinfection. Using bursectomized (BX) or cyclosporin A (CsA)-treated chickens, we performed experiments to determine which type of immunity, humoral or cellular immunity, plays an important role in the resistance of chickens against reinfection with L. caulleryi. BX chickens were inoculated with 2, 20 or 200 sporozoites of L. caulleryi intravenously at 3 weeks of age. Some BX chickens which were inoculated with 2 or 20 sporozoites survived the primary infection. These birds had no parasites in their peripheral blood after challenge infection with 5 x 10(3) sporozoites, even though they had no antibody to L. caulleryi. In contrast, CsA-treated chickens had parasitemia, serum-soluble antigen and antibodies, as did untreated chickens during primary infection. After secondary infection, CsA-treated chickens had parasitemia and serum-soluble antigen, even though they had specific antibodies to L. caulleryi whereas untreated chickens showed no parasitemia. The number of CD4(+), CD8(+), T cell receptor (TCR) alpha ss-bearing cells and TCRgamma delta-bearing cells decreased markedly in the peripheral blood of CsA-treated chickens compared to those of untreated chickens. Lymphocyte proliferation in response to concanavalin A, and T cell growth factor production, were also markedly suppressed in CsA-treated chickens. These results suggest that cell-mediated immunity plays an important role in the development of resistance of chickens against reinfection with L. caulleryi.

Animals↗
PubMed2000

Allelotype and loss of heterozygosity around the L-myc gene locus in primary lung cancers.

L-myc S-allele was reported to be associated with metastasis of lung cancer, indicating the existence of a putative tumor suppressor gene around the L-myc locus, in linkage disequilibrium. The relationship between the S-allele and inactivation of some tumor suppressor gene should be indicated by allelic loss. Therefore, we examined the association between the L-myc S-allele and loss of heterozygosity at 11 loci around the L-myc locus (1p34.3) in primary lesions or other biological characteristics in lung cancer. No associations between the S-allele and allelic loss around the L-myc locus or other characteristics were found. According to the deletion map, three shortest regions of overlap between D1S230 and D1S76 were identified. While loss of heterozygosity at SRO1, between D1S2797 and MYCL1, showed no relationship with the pathological stage, it was more frequently observed in squamous cell carcinoma than adenocarcinoma (P=0.019), and associated with high telomerase activity (P=0.046), an indicator of cellular immortality. In conclusion, we found three shortest regions of overlap (SROs) from D1S2797 to pter, and a tumor suppressor gene, which might be associated with suppression of lung cancer development but not with L-myc S-allele, may exist in SRO1.

Adult↗
PubMed2000

Identification of surface proteins and antigens from larval stages of Ascaris suum by two-dimensional electrophoresis.

An understanding of the biology of the cuticle in the larval stages of Ascariodea is of importance since the cuticle molecules not only possess a variety of functions related to survival but also have a potential role as a target for immunoprophylaxis. Thus, we made a preliminary characterization of surface proteins and antigens from 3rd-stage larvae (L3) and lung-stage larvae of Ascaris suum using two biotin-derivatives and two-dimen sional polyacrylamide gel electrophoresis (2D-PAGE). The proteins labelled with biotin comprised a total of 37 and 32 spots, with molecular weights (Air) ranging from 15 to 101 kDa and isoelectric points (pI) from 3.8 to 7.6, in L3 and lung-stage larvae, respectively. The profiles revealed that the individual spots bound to one or both biotin derivatives. In addition, stage-common and stage-specific spots were found in L3 and lung-stage larvae. 2D-PAGE/immunoblotting analysis was performed with antisera from rabbits repeatedly inoculated with A. suum L3. Nineteen spots were recognized as surface antigens, with Mr ranging from 32 to 66 kDa and pI from 4.9 to 7.6, from L3 and lung-stage larvae after alignment of the immunoblots with the profile of the surface proteins. These spots were found to include stage-common and stage-specific antigens. Identification of surface proteins by biotin labelling combined with 2D-PAGE allows a substantial shortening of sample preparation time for the target proteins, and will be a viable method for protein analysis of surface proteins and antigens of A. suum L3 and lung-stage larvae.

Amino Acid Sequence↗
PubMed2000

Biotin-labeled proteins of Eimeria tenella sporozoite.

To identify surface proteins of eimerian sporozoite, Eimeria tenella sporozoites were labeled with biotin-LC-hydrazide, and analyzed by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and Western blotting. More than 200 sporozoite proteins were recognized with silver staining after 2D-PAGE. Among them, 7 biotin-labeled proteins were detected as surface molecules after Western blotting and reaction with horseradish peroxidase conjugated streptavidin. Their molecular masses ranged from 23 to 117 kilo daltons and their isoelectric points from 4.3 to 6.3. It appears that the biotin-labeling technique can be used to analyze of surface proteins of eimerian parasites.

Animals↗
PubMed2000

[Study on health awareness of home helper for dependent elderly].

The purpose of this study was to investigate the level of oral health awareness and oral health care activities of home helper for dependent elderly. A questionnaire was mailed to persons who took the profession course of care worker training and education (second and third grade) for home helper and short term course (special subject) at care worker support center foundation (33 branches). Responses were obtained from 220 persons qualified as home helpers. Of 220 home helpers, 104 (47.3%) had worked as a home helper for fewer than six years. One hundred forty two (64.5%) were trained and educated for a home helper as a second grade. The results were as follows: 1. One hundred eleven (50.5%) had used a dental floss and an interdental brush. 2. Two hundred eighteen (99.1%) thought it was necessary to perform oral cleaning of dependent elderly. 3. Two hundred fifteen (97.7%) hoped to perform the oral cleaning of dependent elderly. 4. Two hundred nine (95.0%) considered oral cleaning distasteful. 5. Two hundred three (92.3%) recognized food debris between natural teeth and the denture of dependent elderly who could perform oral cleaning themselves. 6. Two hundred three (92.3%) recognized food debris between natural teeth and the denture of dependent elderly who could not perform oral cleaning themselves. 7. One hundred twenty (54.5%) had been trained in oral cleaning for dependent elderly. 8. Two hundred twelve (96.4%) hoped to receive training in oral cleaning for dependent elderly.

Adult↗
PubMed2000

A case of eosinophilic pleural effusion induced by pancreatothoracic fistula.

A 49-year-old man was admitted for evaluation of a left pleural effusion. Thoracenthesis yielded a hemorrhagic pleural effusion with a high percentage of eosinophils (15.9%). Although there were no significant abdominal signs, serological examinations demonstrated a marked increase of pancreatic enzyme activity. Moreover, abdominal CT demonstrated cystic changes between the tail of the pancreas and the spleen. Accordingly ERP was performed under pressure, and contrast medium draining from the pancreas was observed. Pancreatic pleural effusion in this patient consisted of pancreatic juice retained in the thoracic cavity, which resulted from intrapancreatic fistulation connecting to the thoracic cavity due to a pancreatic cyst caused by chronic pancreatitis. The present report indicates that we should investigate the retention of eosinophilic pleural effusion considering not only the possibility of thoracic disease, but also the possibility of a pleural effusion derived from abdominal diseases.

Eosinophilia↗
PubMed2000

[Pilot study of dose intensive weekly chemotherapy followed by cisplatin plus etoposide with concurrent thoracic irradiation for limited-disease small-cell lung cancer. West Japan Thoracic Oncology Group].

It was reported from a previous randomized trial (NEJM 329: 1848, 1993) that a moderate increase in the initial dose of cyclophosphamide and cisplatin improves the survival of patients with LDSCLC. Rapid administration of several active agents over a short treatment period, such as the CODE regimen, is a potentially usefully strategy for increasing the initial dose intensity. Based on these findings, we conducted a pilot study of CODE (C: 25 mg/m2, day 1, weeks 1-4, O: 1 mg/m2, day 1, weeks 2, 4, D: 40 mg/m2, day 1, weeks 1, 3, E: 80 mg/m2, days 1-3, weeks 1, 3) chemotherapy for the first 4 weeks followed by PE therapy (P: 80 mg/m2, day 1, E: 100 mg/m2, days 1-3, for 3 cycles) with concurrent TRT (1.5 Gy bid x 30 fr., total 45 Gy) to treat LDSCLC. From June 1996 through September 1996, 23 patients (pts) were enrolled, among whom 22 were eligible. The patients' characteristics were as follows: median age 65; M/F, 15/7; PS, 0/1/2,9/9/4; Stage II/IIIA/IIIB, 3/8/11. The relative dose intensities in the CODE phase for patients who received this treatment were 107% for P and 156% for E, compared with standard PE therapy. No treatment related death occurred in this series. Myelosuppression was the most frequent toxicity in both treatments. Grade 3 and 4 leukopenia and neutropenia occurred in 73% and 86% of patients in the CODE phase, and in 83% and 91% in the PE phase, respectively. Thrombocytopenia occurred in 14% of the patients in the CODE phase and in 37% in the cisplatin-etoposide phase. Other non-hematological toxicities were mild. There was no severe esophagitis or pneumonitis following radiation therapy. CR was observed in 13 (59%) of the 22 patients, and 9 (41%) patients showed PR, giving an overall response rate of 100%. A median survival time has not yet been ascertained. Our preliminary results indicate that CODE therapy followed by PE therapy with concurrent TRT has very high activity with acceptable toxicities. This treatment regimen should be compared with PE therapy and concurrent TRT in a randomized trial.

Adult↗
PubMed2000

[CPT-11 (irinotecan)--evidence from molecular and pharmacological studies and clinical applications].

Irinotecan (CPT-11) is a derivative of the chemotherapeutic agent Camptothecin. CPT-11 inhibits the nuclear enzyme topoisomerase I. It has demonstrated a broad spectrum of antitumor activity in preclinical tumor model systems. Significant advances have been made toward the understanding of the pharmacokinetics and schedule dependency of this agent. The principal dose limiting toxicities are diarrhea and leukopenia. CPT-11 has been evaluated using a variety of dosing schedules. Two main schedules have been studied and produce similar activity and side-effects: the "Japanese-North American" one where CPT-11 is given at a weekly dose of 100-150 mg/m2 for 4 consecutive weeks followed by a 2 week rest period, and the "European" one-350 mg/m2 every 21 days. CPT-11 has demonstrated significant clinical activity in the treatment of patients with gastrointestinal, pulmonary, gynecologic, and lymphoid malignancies. A recent randomized trial demonstrated a survival advantage in metastatic non-small cell lung cancer and previously untreated metastatic colorectal cancer. Further study of this agent to determine its role in combination chemotherapeutic regimens is currently underway.

Antineoplastic Agents, Phytogenic↗
PubMed1999

Stimulus-coupled interaction of tyrosine hydroxylase with 14-3-3 proteins.

Tyrosine hydroxylase (TH) is phosphorylated by CaM kinase II and is activated in situ in response to a variety of stimuli that increase intracellular Ca(2+). We report here, using baculovirus-expressed TH, that the 14-3-3 protein binds and activates the expressed TH when the enzyme is phosphorylated at Ser-19, a site of CaM kinase II-dependent phosphorylation located in the regulatory domain of TH. Site-directed mutagenesis showed that a TH mutant in which Ser-19 was substituted by Ala retained enzymatic activity at the same level as the non-mutated enzyme, but was a poor substrate for CaM kinase II and did not bind the 14-3-3 protein. Likewise, a synthetic phosphopeptide (FRRAVpSELDA) corresponding to the part of the TH sequence, including phosphoSer-19, inhibited the interaction between the expressed TH and 14-3-3, while the phosphopeptide (GRRQpSLIED) corresponding to the site of cAMP-dependent phosphorylation (Ser-40) had little effect on complex formation. The complex was very stable with a dissociation constant of 3 nM. Furthermore, analysis of PC12nnr5 cells transfected with myc-tagged 14-3-3 showed that 14-3-3 formed a complex with endogenous TH when the cultured cells were exposed to a high K(+) concentration that increases intracellular Ca(2+) and phosphorylation of Ser-19 in TH. These findings suggest that the 14-3-3 protein participates in the stimulus-coupled regulation of catecholamine synthesis that occurs in response to depolarization-evoked, Ca(2+)-dependent phosphorylation of TH.

14-3-3 Proteins↗
PubMed1999

A new boronated porphyrin (STA-BX909) for neutron capture therapy: an in vitro survival assay and in vivo tissue uptake study.

A new boronated porphyrin compound (STA-BX909) was developed as a possible agent for boron neutron capture therapy. The boron concentration was measured by an in vivo rat experimental brain tumor model and an in vitro cell culture study. This agent was compared to sodium borocaptate (BSH) which has been used in clinical trials of boron neutron capture therapy. In the 9L rat brain tumor model, STA-BX909 achieved a higher boron tumor/blood ratio 24 h after injection in comparison to BSH. A boron concentration study in cultured glioma cell lines (U-251, U-87, 9L) demonstrated an increased boron concentration as a function of exposure time to STA-BX909, while the boron concentration remained stable with increasing exposure time to BSH. Use of a colony forming assay with thermal neutron irradiation revealed more cytotoxicity with STA-BX909 than BSH when the same concentration of 10B was administered. We concluded that STA-BX909 may be an effective drug for use in boron neutron capture therapy and that it merits further investigation.

Animals↗
PubMed1999

Activity-independent cell adhesion to tissue-type transglutaminase is mediated by alpha4beta1 integrin.

Transglutaminases (TGases) are enzymes which catalyze cross-link formation between glutamine residues and lysine residues in substrate proteins. We have previously reported that one of the TGases, blood coagulation factor XIIIa (FXIIIa), is capable of mediating adhesion of various cells. In this paper, we report for the first time that tissue-type transglutaminase (TGc) also has cell adhesion activity. TGc-coated plastic surface promoted adhesion and spreading of cells in a TGc concentration-dependent manner. However, there are some obvious differences between cell adhesion mediated by TGc and FXIIIa. As was reported previously, the adhesion to FXIIIa is dependent on its TGase activity. In contrast, the TGc-mediated cell adhesion is independent of its TGase activity: 1) The modification of the active center cysteine with iodoacetamide blocked the enzyme activity without any effect on cell adhesion; 2) the addition of Mg2+ did not induce the enzyme activity, but it was as effective as Ca2+ for cell adhesion; 3) the addition of NH4+ inhibited the enzyme activity but did not affect the cell adhesion significantly. The integrins involved in these cell adhesions are quite different. In the case of FXIIIa, alpha vbeta3 and alpha5beta1 integrins are involved and consequently the RGD peptide substantially inhibited the adhesion. On the other hand, the cell adhesion to TGc is mediated by alpha4beta1 integrin but not alpha5beta1; a CS-1 peptide, which represents the binding site of fibronectin to alpha4beta1 integrin, completely inhibited the cell adhesion to TGc. It is possible that TGc and FXIIIa may mediate cell adhesion under different physiological and pathological situations.

Animals↗
PubMed1999

Clinical features of isolated noncompaction of the ventricular myocardium: long-term clinical course, hemodynamic properties, and genetic background.

OBJECTIVES: A nationwide survey was conducted to clarify the clinical features of isolated noncompaction of the ventricular myocardium (INVM) in Japanese children in comparison with features previously described in patients with INVM. BACKGROUND: Isolated noncompaction of the ventricular myocardium is a rare disorder characterized by an excessively prominent trabecular meshwork. It is accompanied by depressed ventricular function, systemic embolism and ventricular arrhythmia. METHODS: A questionnaire specifically designed for this study was sent to 150 hospitals in Japan where a pediatric cardiology division exists. RESULTS: Twenty-seven patients were diagnosed by two-dimensional echocardiography, their ages ranging from one week to 15 years at presentation, with follow-up lasting as long as 17 years. The gross anatomical appearance and the extension of noncompacted myocardium predominantly at the apex observed on two-dimensional echocardiograms were similar to observations reported previously. Dissimilarities included a greater number of asymptomatic patients at initial presentation, a longer clinical course with gradually depressed left ventricular function, no systemic embolism, and rare ventricular tachycardia in the Japanese children. Cardiac catheterization disclosed normal left ventricular end-diastolic volume and increased left ventricular end-diastolic pressure in most cases, consistent with restrictive hemodynamics. A higher incidence of Wolff-Parkinson-White syndrome was found in the children, whereas left bundle branch block was rarer than reported in adults. Familial recurrence was high (44%) and included many women. CONCLUSIONS: In Japanese children, INVM can be found by screening examinations at asymptomatic stage, and it might have a longer dinical course with gradually depressed left ventricular function and restrictive hemodynamics. The pattern of familial recurrence we observed implies that INVM is a distinctive clinical entity with a heterogeneous genetic background.

Adolescent↗
PubMed1999

Induction of gamma-glutamylcysteine synthetase gene expression by platinum drugs in peripheral mononuclear cells of lung cancer patients.

BACKGROUND: To investigate in vivo the roles of gamma-glutamylcysteine synthetase (gamma-GCS), multidrug resistance-associated protein (MRP), human canalicular multispecific organic anion transporter (cMOAT) and DNA topoisomerase I (topo I) in relation to platinum drug resistance, we monitored the changes of the steady-state levels of the mRNAs for these factors in peripheral mononuclear cells (PMN) after completing platinum drug administration. PATIENTS AND METHODS: PMN from 46 subjects were studied. We obtained PMN from 14 previously untreated lung cancer patients and 14 normal volunteers to measure the baseline gene expression levels. We then obtained PMN from 18 patients with previously untreated advanced lung cancer before and after they received platinum drug treatment. We analyzed the gene expression levels by using the quantitative reverse transcription polymerase chain reaction (RT-PCR). RESULTS: There were no differences in the baseline expression levels between normal volunteers and lung cancer patients in any of the genes. After platinum drug administration, the heavy subunit of gamma-GCS (gamma-GCSh) expression level increased 2.5-fold within 24 hours and the increase persisted for a month, whereas the light subunit of gamma-GCS (gamma-GCSl) expression level did not show an early response but had increased after a month. By contrast, the MRP, cMOAT and topo I expression levels were similar before, during and after chemotherapy. CONCLUSIONS: These results suggest that the gene expression levels of both subunits of gamma-GCS play an important in vivo role in platinum drug resistance.

Adenocarcinoma↗
PubMed1999

Levels of soluble FasL and FasL gene expression during the development of graft-versus-host disease in DLT-treated patients.

Three patients with different clinical symptoms of graft-versus-host disease (GVHD) who had received donor lymphocyte transfusion (DLT) for the treatment of relapsed leukaemia after an allogeneic bone marrow transplantation (BMT) from HLA-matched sibling donors were analysed for the presence of soluble FasL (sFasL) in the sera and for the expression of the Fas ligand (FasL) gene in the peripheral blood mononuclear cells (PBMNC). Two patients who demonstrated liver damage with increased levels of serum bilirubin showed significantly increased levels of serum sFasL. The increase in the sFasL level was observed prior to the increase in the bilirubin during the clinical courses of both patients. The high dose of methyl predonisolone administered to one of these patients greatly reduced the levels of sFasL in the serum. The bilirubin levels were also reduced thereafter. The third patient (without liver damage) did not show any increase in the serum sFasL level. The expression of the FasL gene in the PBMNC of these three patients was examined. All three patients showed increased levels of the FasL gene expression during their clinical courses. However, only one patient showed a parallel alteration of FasL gene expression with sFasL in the serum. These cases provide evidence that the Fas/FasL system is closely associated with human GVHD, especially in the development of liver GVHD.

Adult↗
PubMed1999

Molecular shape and ATP binding activity of rat p50, a putative mammalian homologue of RuvB DNA helicase.

Based on partial amino acid sequences of p50 purified from a high-salt buffer extract of a rat liver nuclear matrix fraction, p50 cDNA was cloned and sequenced, and its amino acid sequence was predicted. The sequence contained helicase motifs, and showed homology with RuvB DNA helicase of Thermus thermophilus and an open reading frame for an unknown 50.5 k protein of Saccharomyces cerevisiae. p50 was expressed as a GST-fusion protein and antiserum against the protein was generated. p50 was localized to the nuclear matrix by cell fractionation and immunoblotting. p50 bound to ATP-Sepharose beads. Ultracentrifugation and gel filtration analyses showed that p50 in rat liver and Xenopus egg mitotic extracts exists as large complexes corresponding to 697 k and 447 k, respectively. A 50 k protein reactive with p50 antibodies was detected not only in rat liver nuclei, but also in a Xenopus egg cytoplasm fraction and a S. cerevisiae extract. This suggests that this putative DNA helicase is present in a wide variety of species ranging from yeast to mammals.

ATPases Associated with Diverse Cellular Activitie↗
PubMed1999

Differential expression of facilitative glucose transporter (GLUT) genes in primary lung cancers and their liver metastases.

Glucose uptake is mediated by members of the facilitative glucose transporter (GLUT) family. Malignant cells take up more glucose than their normal counterparts. The aim of this study was to investigate the gene expression levels of the GLUT family, especially GLUT1, GLUT3, and GLUT5 in primary lung cancer, metastatic liver tumors, and normal lung tissues, and to compare the expression levels of primary and metastatic tumors with those of normal tissues. We analyzed 105 autopsy samples (35 primary lung tumors, 35 corresponding normal lung tissues, 25 normal liver tissues, and 10 metastatic liver tumors) from 35 patients using the quantitative reverse transcription polymerase chain reaction. The GLUT1 gene expression levels in primary lung tumors were significantly higher than those in normal lung tissues. In liver metastatic lesions, the GLUT3 and GLUT5 gene expression levels were significantly higher than those in primary lung tumors, but there were no differences in GLUT1 expression levels between primary and metastatic liver tumors. Our results show that the gene expression pattern of the GLUT family is different between primary and metastatic liver tumors and suggest that the energy transporters in metastatic tumors may be different from those in primary tumors.

Actins↗
PubMed1999

Cyclooxygenase-2 (COX-2) mRNA expression levels in normal lung tissues and non-small cell lung cancers.

One of the cyclooxygenase (COX) isoforms, COX-2, is overexpressed in various human cancers. In this study, we examined the gene expression levels of COX-2 in primary non-small cell lung cancers (NSCLC), metastatic lymph nodes, and normal lung tissues. The expression levels of the COX-2 gene were assessed by means of the reverse transcription polymerase chain reaction in 76 autopsy samples (29 primary NSCLC, 29 corresponding normal lung tissues, and 9 metastatic lymph nodes). The expression levels in NSCLC (both adenocarcinomas and squamous cell carcinomas) were significantly higher than in normal lung tissues and were significantly higher in adenocarcinomas than in squamous cell carcinomas. Differences between the levels of expression of COX-2 in primary tumors and their corresponding metastatic lymph nodes in 9 adenocarcinoma patients were not significant. Our results indicate that COX-2 may be associated with carcinogenesis of NSCLC, and that it may be a target for the treatment of NSCLC.

Adenocarcinoma↗