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I Kawase

Publications and source records attributed to I Kawase.

At least 19 recordsLinked to original sources
PubMed2006

A novel direct competitive repopulation assay for human hematopoietic stem cells using NOD/SCID mice.

BACKGROUND: The major problem in cord blood (CB) transplantation for adult patients is shortage of stem cell number. To overcome this disadvantage, several studies on ex vivo expansion have been performed. However, such efforts are always troubled by the lack of a reliable and simple assay system for stem cells. Our aim was to establish an in vivo assay system to compare the directly repopulating ability of two populations of human hematopoietic stem cells using a xenogeneic transplant system. METHODS: Thirty CB samples from infants of each sex were pooled and enriched for CD34(+) progenitor cells. Enriched CD34(+) cells were transplanted into irradiated NOD/SCID mice at different male to female ratios, and human hematopoietic cells recovered 7 weeks after transplantation were analyzed by a quantitative DNA sex test using competitive PCR for the amelogenin gene. Using this assay system, ex vivo cultured and non-cultured CB cells were compared for repopulating ability. RESULTS: The sex ratio of human CB cells transplanted was found to be maintained for 7 weeks in matured and progenitor cells. The competitive repopulation assay of cultured and non-cultured CB cells showed a marked defect in the repopulating ability of cultured cells, although the LTCIC count was maintained during cultivation. DISCUSSION: Our assay system is a simple and reliable quantitative method that permits direct comparison of two stem cell compartments. The assay system will be useful for the assessment of the functional abilities of various human hematopoietic stem cells.

Adult↗
PubMed2006

Development of WT1 peptide cancer vaccine against hematopoietic malignancies and solid cancers.

Wild-type Wilms' tumor gene WT1 is highly expressed not only in hematopoietic malignancies, including leukemia and myelodysplastic syndromes (MDS), but also in various kinds of solid tumors. Human cytotoxic T lymphocytes (CTLs) which could specifically lyse WT1-expressing tumor cells with HLA class I restriction were generated in vitro. We have also demonstrated that mice immunized with the WT1 peptide or WT1 cDNA rejected challenges by WT1-expressing tumor cells and survived with no signs of auto-aggression to normal organs which physiologically expressed WT1 in prophylactic and therapeutic models. Furthermore, we and others detected IgM and IgG WT1 antibodies in the patients with hematopoietic malignancies, indicating that WT1 protein was highly immunogenic, and that immunoglobulin class-switch-inducing WT1-specific cellular immune responses were elicited in the patients. CD8+ WT1-specific CTLs were also detected in peripheral blood or tumor-draining lymph nodes of cancer patients. These results provided us with the rationale for elicitation of CTL responses targeting the WT1 product for cancer immunotherapy. On the basis of the findings mentioned above, we performed a phase I clinical trial of WT1 peptide cancer vaccine for the patients with malignant neoplasms. These results strongly suggested that WT1 peptide cancer vaccine had efficacy in the clinical setting, because clinical responses, including reduction of leukemic blast cells or regression of tumor masses, were observed after the WT1 vaccination in patients with hematopoietic malignancies or solid cancers. The power of TAA-derived cancer vaccine may be enhanced by combination with stronger adjuvants, helper peptide, or conventional treatments such as molecular-target-based drugs.

Animals↗
PubMed2005

Th1-biased humoral immune responses against Wilms tumor gene WT1 product in the patients with hematopoietic malignancies.

The Wilms' tumor gene WT1 is highly expressed in leukemias and myelodysplastic syndrome (MDS), and WT1 expression levels increase along with the disease progression in chronic myeloid leukemia and MDS. We previously reported that IgM and IgG WT1 antibodies were detected with significantly higher detection rate and antibody titers in leukemias and MDS compared to those in healthy volunteers. In this study, whether IgG humoral immune responses against WT1 protein were Th1- or Th2-type were determined by measurement of four subclasses of IgG WT1 antibody, IgG1, IgG2, IgG3, and IgG4. In leukemias and MDS, Th1-type WT1 antibodies such as IgG1, IgG2, and IgG3 were significantly increased in both detection rate and antibody titers compared to those in healthy volunteers, whereas Th2-type WT1 antibody such as IgG4 did not increase. These results showed that Th1-biased humoral immune responses against WT1 protein were generated in leukemias and MDS. These results should allow us to consider that Th1-biased cellular immune responses against WT1 protein, which was essentially needed for cancer immunotherapy targeting WT1, should be elicited in patients with hematopoietic malignancies.

Antibody Formation↗
PubMed2005

HLA-haploidentical nonmyeloablative stem cell transplantation: induction to tolerance without passing through mixed chimaerism.

There are few reports of unmanipulated HLA-haploidentical nonmyeloablative stem cell transplantation (NST) using only pharmacological acute graft-vs.-host disease (GVHD) prophylaxis. We present here a successful case of unmanipulated HLA-haploidentical NST for mediastinal large B cell lymphoma that was resistant to autologous peripheral blood stem cell transplantation (PBSCT). The conditioning regimen consisted of fludarabine, busulfan and rabbit anti-T-lymphocyte globulin (ATG) in addition to rituximab. GVHD prophylaxis was performed using tacrolimus and methylprednisolone 1 mg/kg. The patient had rapid engraftment, with 100% donor chimaerism in the lineages of both T cells and granulocytes on day +12, but developed no GVHD clinically. The patient is still in complete remission past day +1020, with no sign of chronic GVHD without receiving immunosuppressive agents. HLA-haploidentical NST may be performed without utilizing mixed chimaerism.

Adult↗
PubMed2004

Identification of a gene element essential for leukemia-specific expression of transgenes.

Leukemia-specific promoters and enhancers for gene therapy had never been reported. Since the Wilms' tumor gene WT1 is overexpressed in almost all types of leukemia, WT1 is an ideal target of leukemia-specific therapy. To explore the possibility of gene therapy for leukemia using WT1 promoter and enhancer, their activities in several kinds of cells were analyzed by using the enhanced green fluorescent protein (EGFP) gene as a reporter. First, we identified the best combination (654P/EGFP/int3- enh/3'-enh vector) of the 654-bp WT1 promoter and the two WT1 enhancers located in intron 3 and at the 3' end of the WT1 gene for inducing EGFP expression in K562 cells, which endogenously expressed WT1. When this was transfected into WT1-expressing leukemia cells (K562, HEL), WT1-nonexpressing hematopoietic cells (Daudi, U937), and WT1-expressing nonhematopoietic cells (TYK-nu-CPr, SW480, 293 T), 19.8, 22.9, 1.47, 1.43, 4.50, 4.16, and 1.09 times EGFP expression was induced, respectively, compared to that by the promoter-less EGFP vector. These results showed that the 654P/EGFP/int3-enh/3'-enh vector specifically induced high levels of EGFP expression in WT1-expressing leukemia cells. 654P/int3- enh/3'-enh vector containing transgenes such as suicide genes might become useful tools for leukemia-specific gene therapy.

Enhancer Elements, Genetic↗
PubMed2004

Preferential expression of the vasoactive intestinal peptide (VIP) receptor VPAC1 in human cord blood-derived CD34+CD38- cells: possible role of VIP as a growth-promoting factor for hematopoietic stem/progenitor cells.

Primitive hematopoietic progenitor cells such as severe combined immunodeficiency- repopulating cells and long-term culture-initiating cells are enriched in CD34+CD38- cells derived from various stem cell sources. In this study, to elucidate the features of such primitive cells at the molecular level, we tried to isolate genes that were preferentially expressed in umbilical cord blood (CB)-derived CD34+CD38- cells by subtractive hybridization. The gene for VPAC1 receptor, a receptor for the neuropeptide vasoactive intestinal peptide (VIP), was thereby isolated and it was shown that this gene was expressed in both CD34+CD38- and CD34+CD38+ CB cells and that the expression levels were higher in CD34+CD38- CB cells. Next, we assessed the effects of VIP on the proliferation of CD34+ CB cells using in vitro culture systems. In serum-free single-cell suspension culture, VIP enhanced clonal growth of CD34+ CB cells in synergy with FLT3 ligand (FL), stem cell factor (SCF), and thrombopoietin (TPO). In serum-free clonogenic assays, VIP promoted myeloid (colony-forming unit-granulocyte/macrophage (CFU-GM)) and mixed (CFU-Mix) colony formations. Furthermore, in Dexter-type long-term cultures, VIP increased colony-forming cells at week 5 of culture. These results suggest that VIP functions as a growth-promoting factor of CB-derived hematopoetic progenitor cells.

ADP-ribosyl Cyclase↗
PubMed2004

Strong association of C-reactive protein with body mass index and 2-h post-challenge glucose in non-diabetic, non-smoker subjects without hypertension.

AIMS: Increases in C-reactive protein (CRP) levels have been shown to be associated with cardiovascular diseases as well as asymptomatic atherosclerosis and to be closely related to traditional cardiovascular risk factors. The aim of this study was to determine the clinical and biochemical characteristics associated with CRP in non-diabetic, non-smoker subjects without hypertension. METHODS: A 75-g oral glucose tolerance test was performed on 305 Japanese subjects aged 40-70 years who were undergoing health examinations. We recruited non-diabetic, non-smoker subjects without hypertension. Subjects with known cardiovascular diseases, chronic or acute inflammation, malignant diseases, or autoimmune disorders were excluded. Plasma high-sensitivity CRP was measured in 125 subjects who satisfied the admission criteria. RESULTS: Plasma CRP levels were significantly higher in the 28 subjects with impaired glucose tolerance (IGT) than that in the 97 subjects with normal glucose tolerance (NGT) (median 0.53, range 0.18-1.10 mg/l vs. median 0.32, range 0.17-0.49 mg/l; P = 0.032). There was a positive correlation of CRP with body mass index (BMI), triglycerides, uric acid, fasting glucose, oral glucose tolerance test (OGTT) 1-h glucose, OGTT 2-h glucose, and a negative correlation with HDL cholesterol. Multivariate regression analysis identified BMI (F = 8.57, P = 0.004) and OGTT 2-h glucose (F = 5.96, P = 0.016) as independent predictors for CRP. CONCLUSIONS: BMI and OGTT 2-h glucose are the most important predictors for plasma CRP in non-diabetic, non-smoker subjects without hypertension.

Adult↗
PubMed2004

Absence of mutations in the Wilms' tumor gene wt1 in de novo non-small cell lung cancers.

We recently demonstrated that the WT1 gene was overexpressed in the majority of de novo lung cancers regardless of cancer subtypes. Here, we examined WT1 genomic DNA in 38 cases of de novo non-small cell lung cancers (NSCLC) for mutations using direct sequencing. The sequencing analysis showed no mutations of WT1 genomic DNA in any of 38 de novo non-small cell lung cancers examined. These results indicated that the non-mutated, wild-type WT1 gene played an important role in de novo NSCLC.

Adult↗
PubMed2003

Risk factors for asymptomatic atherosclerosis in Japanese type 2 diabetic patients without diabetic microvascular complications.

Atherosclerotic vascular diseases are frequently associated with diabetes mellitus. There has been increasing evidence showing that the atherosclerotic diseases in diabetic patients are distinct from diabetic microvascular complications as to their pathophysiology and epidemiology. However, we have no information on the prevalence of asymptomatic atherosclerosis in diabetic patients before the onset of microvascular diseases. In the present investigation, we aimed to evaluate risk factors for the atherosclerosis in type 2 diabetic patients without the microvascular diseases. For this purpose, we evaluated atherosclerotic change of carotid arteries in 125 Japanese type 2 diabetic patients who had neither atherosclerotic vascular diseases nor diabetic microvascular complications. When atherosclerotic change was defined as the mean intima-media thickness (IMT) of >/= 1.1 mm and/or the presence of plaque lesion, 50% of patients had atherosclerosis of the carotid arteries. Risk factors for the carotid atherosclerosis were age, low-density lipoprotein (LDL)-cholesterol, hypertension, and diabetes treatment. Age and LDL-cholesterol were associated with mean IMT. Age, diabetes treatment, LDL-cholesterol, and hypertension were positively associated with plaque lesion, while high-density lipoprotein (HDL)-cholesterol was negatively associated with it. Fasting plasma glucose, glycosylated hemoglobin (HbA(1c)), and known diabetes duration remained unassociated with any parameters of asymptomatic atherosclerosis of the carotid arteries. These results indicate that glycemic control is unrelated with asymptomatic atherosclerosis in type 2 diabetic patients without diabetic microvascular complications. Conventional risk factors and diabetes treatment are independently associated with atherosclerosis of the carotid arteries in these patients.

Aged↗
PubMed2003

Successful treatment of bcr/abl-positive acute mixed lineage leukemia by unmanipulated bone marrow transplantation from an HLA-haploidentical (3-antigen-mismatched) cousin.

We describe a patient with bcr/abl-positive acute mixed lineage leukemia who successfully underwent transplantation in primary induction failure, using unmanipulated bone marrow from a human leukocyte antigen (HLA)-haploidentical cousin. The tumor burden was successfully reduced by the administration of imatinib mesylate (STI571) before transplantation. As graft-versus-host disease (GVHD) prophylaxis, a combination of tacrolimus and a short course of methotrexate, methylprednisolone, and mycophenolate mofetil was used. Hematopoietic reconstitution was rapid, and acute GVHD was limited to the skin (grade I). The patient is still in complete remission past day +400. This successful case suggests that HLA-haploidentical transplantation using unmanipulated marrow from a distantly related relative can be considered for patients in urgent situations who do not have HLA-identical donors.

Adult↗
PubMed2003

Administration of anti-interleukin 18 antibody fails to inhibit development of dermatitis in atopic dermatitis-model mice NC/Nga.

BACKGROUND: Interleukin (IL)-18 has been shown to activate basophils to produce histamine and IL-4 and to induce naive T cells to differentiate into T-helper (Th) 2 cells. However, when expressed together with IL-12, IL-18 induces Th1 cell development and inhibits IgE synthesis. Previously we reported that serum IL-18 levels were elevated in the sera from atopic dermatitis-model mice NC/Nga, prior to the onset and during the development of dermatitis. OBJECTIVES: We studied whether neutralization of IL-18 activity might affect dermatitis in NC/Nga mice, to investigate the role of IL-18 on dermatitis. METHODS: NC/Nga mice were given weekly anti-IL-18 antibody starting at 5 weeks of age to 13 weeks and development of dermatitis, scratching behaviour and serum IgE concentrations were evaluated. RESULTS: Continuous injections of anti-IL-18 antibody failed to inhibit the onset and development of dermatitis and IgE elevation. The treatment, rather, tended to lead to an exacerbation of dermatitis and scratching behaviour. In addition, the administration of anti-IL-18 antibody did not ameliorate the responsiveness of lymphocytes to IL-4, which was previously demonstrated as an immunological abnormality in the mouse. CONCLUSION: This study demonstrates that, at least in NC/Nga mice, IL-18, although excessively expressed before the onset of dermatitis, shows antiallergic actions.

Animals↗
PubMed2003

Association between interleukin-18 gene polymorphism 105A/C and asthma.

BACKGROUND: IL-18 has been shown to exert anti-allergic or allergy-promoting activities, but the existence of genetic polymorphisms in the coding regions of IL-18 gene has not been demonstrated. OBJECTIVE: The aim of this study was to investigate whether polymorphism is present in the coding regions of the IL-18 gene and, if so, to further analyse the association between polymorphism and asthma in a case-control study. METHODS: We screened the coding regions of the IL-18 gene for polymorphisms by using PCRsingle-stranded conformation polymorphism and direct sequencing of PCR products, followed by analysis of the association between polymorphism and asthma. RESULTS: We identified one polymorphism (105A/C) in the coding regions. The frequency of the 105A allele was significantly higher in asthmatic patients than in controls (P<0.01; odds ratio (OR)=1.83 (1.37-2.26)). Significant linkage disequilibrium was observed between the 105A/C and -137G/C polymorphisms in the 5' flanking region of the IL-18 gene (D=0.58, P<0.0001). However, in asthmatic patients the 105A allele was not associated with either total serum IgE or IL-18 levels. CONCLUSION: The 105A/C polymorphism of the IL-18 gene may be associated with the pathogenesis of asthma.

Adolescent↗
PubMed2000

Thickened intima of the aortic arch is a risk factor for stroke with coronary artery bypass grafting.

BACKGROUND: Perioperative stroke is one of the most serious complications of cardiac surgery. METHODS: Using transesophageal echocardiography, we estimated the intimal thickness of the thoracic aorta as an index of the severity of aortic atherosclerosis to determine the risk of stroke in coronary artery bypass grafting (CABG) patients. The study population comprised 315 consecutive patients who underwent isolated CABG with cardiopulmonary bypass. RESULTS: Five patients (1.6%) had perioperative cerebral stroke or systemic emboli. We compared the mean intimal thicknesses of the ascending aorta, aortic arch, and descending aorta. Mean thicknesses in patients without stroke were 2.07 +/- 0.76, 2.78 +/- 1.15, and 2.32 +/- 1.21 mm, respectively, and mean thicknesses in the stroke patients were 1.94 +/- 0.55, 6.94 +/- 3.79, and 3.39 +/- 1.85 mm, respectively. The patients with an intima of more than 5 mm at the aortic arch had a significantly greater incidence of perioperative stroke (p = 0.007). CONCLUSIONS: These results suggest that patients who have an aortic arch intima thickened to more than 5 mm are at a significantly high risk for perioperative stroke, and thus, the CABG procedure should be carefully evaluated to prevent such complications.

Aged↗
PubMed2000

Prognostic significance of hTERT expression in non-small cell lung cancer.

To investigate the prognostic role of hTERT expression in non-small cell lung cancer (NSCLC), we examined the expression of hTERT mRNA in tumor specimens from 68 patients with NSCLC using RT-PCR. The expression of hTERT was detected in 34 (50%) of 68 cancer tissues. There were no correlations between hTERT status and any common clinical features except age. Patients with hTERT expression had shorter survival than those without hTERT expression. Multivariate analysis showed that hTERT expression was an independent negative prognostic factor. These results suggest that expression of hTERT may be an independent prognostic factor for NSCLC patients.

Aged↗
PubMed1998

Lung cancer: intermittent irradiation synchronized with respiratory motion--results of a pilot study.

PURPOSE: To test the feasibility of a system for intermittent irradiation synchronized with respiratory motion in a clinical setting. MATERIALS AND METHODS: A newly developed gate pulse controller that starts and stops irradiation at a chosen phase of the respiratory cycle by controlling a linear accelerator was used in six patients with lung cancer. A laser displacement sensor was used for the detection of respiratory motion. Three patients underwent radiation therapy during the cycles between 50% expiration and 50% inspiration (step 1), and three patients underwent radiation therapy during the cycles between 70% expiration and 30% inspiration (step 2). RESULTS: The system functioned well; irradiation was verified with portal verification radiography in all six patients. The range of the tumor position during synchronized irradiation was detectable with fast portal localization radiography. The treatment times for steps 1 and 2 were 1.38-1.71 and 2.03-2.18 times longer, respectively, than those for conventional irradiation. CONCLUSION: Synchronized irradiation with the authors' system allowed convenient and reliable reduction of the target volume. Further study is needed to standardize the system for clinical use.

Clinical Protocols↗
PubMed1998

Limited-stage small cell lung cancer: local failure after chemotherapy and radiation therapy.

PURPOSE: To evaluate radiation therapy regimens for improvement in local control in patients with limited-stage small cell lung cancer. MATERIALS AND METHODS: Radical radiation therapy results in 117 patients with limited-stage small cell lung cancer were retrospectively reviewed. The protocols in 90 patients were 40 Gy in 20 fractions (n = 28), 50 Gy in 25 fractions (n = 32), and 45 Gy in 30 fractions (accelerated hyperfractionation, n = 30). The other 27 patients received thoracic irradiation (dose range, 20-60 Gy; median dose, 54 Gy). All patients underwent systemic chemotherapy. RESULTS: The 5-year Kaplan-Meier survival rates in the patients with N0, N1, N2, and N3 disease were 26%, 34%, 18%, and 0%, respectively; the rates of in-field relapse were 25%, 36%, 26%, and 25%, respectively; and the rates of marginal relapse were 0%, 9%, 15%, and 29%, respectively. In 56% of patients with marginal relapse, the relapse site was at the upper margin. The 4-year in-field control rates for the patients who underwent 40, 50, and 45 Gy were 51%, 70%, and 56%, respectively. CONCLUSION: Patients with N3 limited-stage small cell lung cancer should undergo a separate protocol, and the upper margin should be extended in patients with N2 or N3 disease.

Adult↗
PubMed1998

Combination of irinotecan and etoposide for treatment of refractory or relapsed small-cell lung cancer.

PURPOSE: To determine the response rate, survival, and toxicity of irinotecan (CPT-11), a topoisomerase I inhibitor, combined with etoposide, a topoisomerase II inhibitor, in refractory or relapsed small-cell lung cancer (SCLC). PATIENTS AND METHODS: Twenty-five patients with refractory or relapsed SCLC were entered onto the trial. All 25 patients had been pretreated with some form of cisplatin-based combination chemotherapy and had also received previous etoposide- or anthracyclinecontaining chemotherapy. The median time off chemotherapy was 6.7 months (range, 0.9 to 23.5). Patients were treated at 4-week intervals using CPT-11 (a starting dose of 70 mg/m2 intravenously on days 1, 8, and 15) plus etoposide (80 mg/m2 intravenously on days 1 to 3), with a subsequent dose based on toxicity. In addition, recombinant human granulocyte colony-stimulating factor (rhG-CSF; 2 microg/kg/d) was given from day 4 to day 21, except on the days of CPT-11 administration. RESULTS: All patients were assessable for toxicity and survival. Twenty-four patients were assessable for response. There were 14 partial responses (PRs) and three complete responses (CRs), for an overall response rate of 71% (95% confidence interval, 53% to 89%). The median response duration was 4.6 months. Median survival was 271 days. Major toxicities were myelosuppression (predominantly leukopenia) and diarrhea. Grade 3 to 4 neutropenia and thrombocytopenia occurred in 56% and 20% of patients, respectively. Grade 3 to 4 diarrhea was observed in 4%. There was one treatment-related death due to severe myelosuppression. CONCLUSION: A combination of CPT-11 and etoposide with rhG-CSF support is an active therapy against refractory or relapsed SCLC and deserves to be studied more extensively in a phase III trial.

Adult↗