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Biomedical subjects

M Kawakami

Publications and source records attributed to M Kawakami.

At least 19 recordsLinked to original sources

Antiapoptotic function of 17AA(+)WT1 (Wilms' tumor gene) isoforms on the intrinsic apoptosis pathway.

The WT1 gene is overexpressed in human primary leukemia and a wide variety of solid cancers. The WT1 gene is alternatively spliced at two sites, yielding four isoforms: 17AA(+)KTS(+), 17AA(+)KTS(-), 17AA(-)KTS(+), and 17AA(-)KTS(-). Here, we showed that 17AA(+)WT1-specific siRNA induced apoptosis in three WT1-expressing leukemia cell lines (K562, HL-60, and Kasumi-1), but not in WT1-non-expressing lymphoma cell line (Daudi). 17AA(+)WT1-specific siRNA activated caspase-3 and -9 in the intrinsic apoptosis pathway but not caspase-8 in the extrinsic one. On the other hand, 17AA(-)WT1-specific siRNA did not induce apoptosis in the three WT1-expressing cell lines. The apoptosis was associated with activation of proapoptotic Bax, which was activated upstream of the mitochondria. Constitutive expression of 17AA(+)WT1 isoforms inhibited apoptosis of K562 leukemia cells induced by apoptosis-inducing agents, etoposide and doxorubicin, through the protection of mitochondrial membrane damages, and DNA-binding zinc-finger region of 17AA(+)WT1 isoform was essential for the antiapoptotic functions. We further studied the gene(s) whose expression was altered by the expression of 17AA(+)WT1 isoforms and showed that the expression of proapoptotic Bak was decreased by the expression of 17AA(+)KTS(-)WT1 isoform. Taken together, these results indicated that 17AA(+)WT1 isoforms played antiapoptotic roles at some points upstream of the mitochondria in the intrinsic apoptosis pathway.

Apoptosis↗

Posterior endoscopic surgery for lumbar disc herniation with contralateral symptoms - a report of two cases.

We report two cases of lumbar disc herniation with contralateral nerve root involvement, surgically treated with a microendoscopic disectomy system (METRx-MED system). The nerve root of the symptomatic side (contralateral to the side of the disc herniation) had been compressed to the superior facet by herniated disc from the opposite side. Endoscopic observation revealed inflammatory findings of the nerve root on the symptomatic side, such as fibrosis, adhesion, redness and swelling. In contrast, on the non-symptomatic side (ipsilateral side of the disc herniation), the nerve root had been merely compressed by the herniated disc but did not demonstrate any inflammatory findings. Excision of the herniated disc and decompression of the non-symptomatic nerve root should be done first, approaching from the disc herniation side. After that, through the same approach, the nerve root of the opposite (symptomatic) side should be decompressed.

Adolescent↗

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↗

Morphological differences in the temporomandibular joints in asymmetrical prognathism patients.

OBJECTIVE: To investigate the morphology of the temporomandibular joints (TMJ) in skeletal asymmetry with prognathism. DESIGN: Three-group observational clinical study. SETTING AND SAMPLE POPULATION: University setting. Thirty-five patients undergoing orthognathic surgery without signs and symptoms of TMJ disorder were assigned to three groups (right deviation, n = 11; left deviation, n = 14; and non-deviation; n = 10) based on anteroposterior cephalometric analysis. OUTCOME MEASURE: Positional and morphological differences of the TMJs were evaluated using a total of 70 bilateral sagittal TMJ magnetic resonance images. RESULTS: In both the right and left deviation groups, the TMJ on the deviated side showed a significantly steeper eminence than that on the non-deviated side (p < 0.05). The anterior joint space was narrower on the deviated side than on the non-deviated side whereas the posterior joint space did not differ markedly, indicating an anterior position of the condyle in the glenoid fossa of the TMJ on the deviated side. Disk displacement comparisons revealed no significant differences between left and right sides in the symmetry or asymmetry group. CONCLUSION: Asymmetrical prognathism patients exhibit significant morphological differences between the right and left TMJs concerning the slope of the articular eminence, which correspond to facial asymmetry.

Adolescent↗

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↗

Plasma level of a 5-fluorouracil metabolite, fluoro-beta-alanine correlates with dihydropyrimidine dehydrogenase activity of peripheral blood mononuclear cells in 5-fluorouracil treated patients.

5-fluorouracil (5-FU) is mostly metabolized after administration, and the metabolizing enzyme, dihydropyrimidine dehydrogenase (DPD), seems to be the rate-limiting factor. However, there are few reports on the final metabolite, fluoro-beta-alanine (FBAL). We report here the results of determination of the FBAL level in 5-FU treated patients and the correlation between the FBAL level and the DPD activity in peripheral blood mononuclear cells (PBMCs). Blood samples were collected from 20 patients, who had received continuous intravenous infusion (CIV) of 5-FU (320 mg/m2/24 hr) after resection of colorectal cancer, and the FBAL level was determined by high performance liquid chromatography (HPLC), after derivatizing into o-phthalaldehyde (OPA) and detecting fluorescence. DPD activity was measured in cytosol prepared from PBMCs using HPLC radioassay. The average FBAL plasma level during CIV of 5-FU was 911.0 ng/ml (521.0 to approximately 1834.6 ng/ml) and that of DPD activity in PBMCs was 282.6 pmol/min/mg-protein (145.0 to approximately 568.0 pmol/min/mg-protein). There was a significant correlation between the FBAL level and the DPD activity (r=0.805, p<0.0001). FBAL level in plasma may be useful in predicting the DPD activity in PBMCs, however, further studies are required considering the small number of cases in this study.

Aged↗

Neurovirulence of H7N7 influenza A virus: brain stem encephalitis accompanied with aspiration pneumonia in mice.

A mouse-adapted influenza A virus, A/equine/London/1416/73-MA (H7N7) caused viral pneumonia, ganglionitis and encephalitis after intranasal inoculation in mice. Virological and pathological data suggested that this virus spreads to the brain by both hematogenous and transneuronal routes, and produces encephalitic lesions similar to those seen in mice infected with H5 highly pathogenic avian influenza A viruses by intranasal infection. Some mice infected with this strain were affected by aspiration pneumonia, which may be caused by neurogenic dysfunction of the pharyngeal/laryngeal reflex due to brain stem encephalitis.

Animals↗

Enzyme replacement therapy in Japanese Fabry disease patients: the results of a phase 2 bridging study.

Fabry Disease (alpha-galactosidase A deficiency) is an X-linked hereditary disorder leading to the pathological accumulation of globotriaosylceramide (GL-3) in lysosomes, particularly in the vascular endothelium of the kidney, heart and brain. We report the results of an open-label phase 2 study that was undertaken to evaluate whether ethnic differences exist that would affect agalsidase beta (Fabrazyme) treatment of Fabry patients in the Japanese population, relative to safety and efficacy. The study design mirrored the design of the completed phase 3 clinical trial that led to approval of the product agalsidase beta. The 13 Japanese, male Fabry patients enrolled in the study received the enzyme replacement therapy over a period of 20 weeks as biweekly infusions. All selected efficacy end points showed improvements that were comparable with findings from the phase 3 study. These improvements included reductions of GL-3 accumulation in both kidney and skin capillary endothelial cells to (near) normal levels (92% of patients). Kidney and plasma GL-3 levels decreased by 51.9% and 100%, respectively, by ELISA. Renal function remained normal. Fabry-associated pain, and quality of life, showed improvement over baseline in multiple categories. Related adverse events were mild or moderate in intensity and mostly infusion-associated (fever and rigors). As expected, IgG antibody formation was observed in 85% of the patients, but had no effect on treatment response. These results suggest that treatment with agalsidase beta is safe and effective in Japanese patients with Fabry disease. With regard to safety and efficacy, no differences were observed as compared to the caucasian population.

Adult↗

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↗

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↗

Importance of transition zone prostate biopsies in patients with gray-zone PSA levels undergoing the ultrasound-guided systematic ten-biopsy regimen for the first time.

INTRODUCTION: We analyzed the efficacy of routine transition zone biopsies for patients undergoing ultrasound-guided systematic prostate biopsies for the first time because of an elevated serum prostate-specific antigen (PSA) level. PATIENTS AND METHODS: Using the systematic ten-biopsy regime, four additional transition zone biopsies were performed in 236 consecutive patients, because they showed an elevated PSA level (range 4.0- 9.9 ng/ml). RESULTS: The overall prostate cancer detection rate was 21.2% (50/236). In 24 patients (48.0%), cancers were detected only in the peripheral zone, in 4 (8.0%) only in the transition zone, and in 22 (44.0%) in both zones. No distinguishing characteristics could be determined for the cancers detected in the transition zone only. CONCLUSIONS: Although the cancer detection rate for the transition zone was significantly lower than for the peripheral zone, it was higher than that reported in most other studies which may have included biopsy specimens from patients with advanced prostate cancers. The usefulness of transition zone biopsies for the detection of early-stage prostate cancer, especially in patients with a PSA gray zone, can, therefore, not be denied.

Adult↗

The interplay between gastric cancer cell lines and PBMCs mediated by the CC chemokine RANTES plays an important role in tumor progression.

In the present study, we investigated the effect of the RANTES-mediated interaction between gastric carcinoma cell lines and peripheral blood mononuclear cells (PBMCs) in tumor progression. RANTES production in PBMCs stimulated by highly metastatic cancer cell line-conditioned supernatants was higher than in those stimulated by a less metastatic gastric cancer cell line-conditioned supernatant. RANTES receptors were expressed in PBMCs, but not in those cancer cell lines; therefore it was suggested that RANTES might affect PBMCs but not cancer cells. Matrix metalloproteinase (MMP)-9 expression in PBMCs was examined. Similar to RANTES production, MMP-9 expression in PBMCs stimulated by highly metastatic cell line-conditioned supernatants was higher than in that stimulated by a less metastatic cell line-conditioned supernatant. Invasion assays of gastric cancer cell lines were performed. Cancer cells cultured with PBMCs invaded into Matrigel more frequently than those without PBMCs. This invasive activity was highly inhibited by an anti-RANTES antibody. These results suggest that tumor cells can acquire the potential for invasion by cooperating with PBMCs and RANTES plays an important role in the interplay between tumor cells and PBMCs. It is thus thought that RANTES might be a candidate molecular target in the therapeutic strategy for gastric cancers.

Base Sequence↗

Usefulness of switching to cabergoline from other dopamine agonists in patients with advanced Parkinson's disease.

Problems associated with long-term treatment of advanced Parkinson's disease (PD) include motor complications and psychotic and autonomic symptoms. We switched patients from bromocriptine (BR) or pergolide (PER) to cabergoline (CB) therapy and investigated CB's usefulness in alleviating such problems. Subjects were 30 patients (mean age 68.2 years; 13 receiving BR, 17 PER) with PD complicated by effects of long-term treatment but in whom their dose of dopamine (DA) agonist was contraindicated due to adverse reactions. Patients were switched to CB over a 2-4-week period. Hoehn-Yahr and Unified Parkinson Disease Rating Scale (UPDRS) I-IV "on" and "off" scores improved in both the BR and PER groups. CB was not discontinued due to adverse reactions in any patient. In conclusion, switching to CB is useful in patients in whom it is problematic to increase their dose of DA agonist due to motor complications or psychotic symptoms of advanced PD.

Aged↗

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↗

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↗

A new form of retinopathy associated with myocardial infarction treated with percutaneous coronary intervention.

AIM: To report a new form of retinopathy that was observed in patients who had undergone percutaneous coronary intervention (PCI) following acute myocardial infarction (AMI). METHODS: Serial ophthalmological examinations were conducted in 40 patients who underwent PCI. Thirty patients were diagnosed with AMI, and another 10 had stable angina pectoris. RESULTS: Cotton wool spots developed in 17 (57%) patients from the group with AMI undergoing PCI (n = 30) within 2 months. Of these, 41% (seven patients) also developed superficial haemorrhages. Retinopathy was most prominent 1-2 months after AMI and then tended to become quiescent afterwards, without treatment. CONCLUSION: We have identified a new form of retinopathy in patients with AMI that spontaneously subsides without treatment.

Adult↗

Nicorandil versus isosorbide dinitrate as adjunctive treatment to direct balloon angioplasty in acute myocardial infarction.

OBJECTIVE: To compare the effects of nicorandil (a hybrid ATP sensitive potassium channel (K+(ATP) channel) opener/nitric oxide donor) with those of isosorbide dinitrate (ISDN) on myocardial microcirculation and cardiac function in patients with acute myocardial infarction (AMI) who had undergone reperfusion treatment by direct balloon angioplasty. DESIGN: Double blind randomised study. PATIENTS: 60 patients with AMI in Killip class I. INTERVENTIONS: Patients were assigned into two treatment groups: a nicorandil group (n = 30) and an ISDN group (n = 30). Each drug was infused intravenously at 6 mg/h for 72 hours starting at admission and was administered directly to the treated coronary artery immediately after angioplasty. RESULTS: Compared with ISDN, nicorandil more frequently caused recovery of ST segment elevation just after reperfusion (15 of 27 (55.5%) in the nicorandil group v 5 of 26 (19.2%) in the ISDN group, p = 0.006). The nicorandil group had higher values of averaged peak velocity 40 minutes after reperfusion (mean (SD) 24.8 (13.3) cm/s v 16.0 (11.1) cm/s, p = 0.045) and higher values of regional wall motion of the infarcted area three weeks after onset of AMI (-1.78 (1.11) v -2.50 (1.04) SD/chord, p = 0.046). CONCLUSIONS: A combination of nicorandil drip infusion starting before reperfusion and intracoronary injection immediately after reperfusion is more effective than a similarly performed infusion of ISDN in preserving myocardial microcirculation in the reperfused AMI area. The nicorandil regimen resulted in better left ventricular regional wall motion.

Angioplasty, Balloon↗