Biomedical subjects

Noriko Usui

Publications and source records attributed to Noriko Usui.

At least 37 records · Page 2Linked to original sources

PubMed2004

Intravenous administration of 2,7,8-trimethyl-2-(beta-carboxyethyl)-6-hydroxy chroman (gamma-CEHC) to rats and determination of its plasma concentration and urinary sodium excretion.

A natriuretic hormone, 2,7,8-trimethyl-2-(beta-carboxyethyl)-6-hydroxy chroman (gamma-CEHC) was administered intravenously to male Sprague-Dawley rats and the plasma concentration of gamma-CEHC along with urinary sodium (Na+) excretion was investigated. The plasma gamma-CEHC concentrations were fluorimetrically determined by a column-switching HPLC method consisting of both phenyl and octadecyl silica columns, following a pre-column fluorescence derivatization with a fluorescence reagent, 4-N,N-dimethylaminosulfonyl-7-piperazino-2,1,3-benzoxadiazole (DBD-PZ). In rats fed with a high-NaCl (8.0%) diet, plasma gamma-CEHC concentrations rapidly decreased by 20% in 15-45 min after the administration of gamma-CEHC, while Na+ excretion gradually increased with time. Considering these results, the Na+ excretion effect appeared not to be associated with plasma gamma-CEHC concentration. In addition, attempts were made to examine a main urinary metabolite of gamma-CEHC, a large amount of 6-O-sulfated gamma-CEHC found to be present in the urine using an HPLC-tandem mass spectrometry. Thus, it is plausible that gamma-CEHC was easily metabolized to 6-O-sulfated metabolite and excreted into urine in rats.

Animals↗

PubMed2004

An automated analyzer for vancomycin in plasma samples by column-switching high-performance liquid chromatography with UV detection.

An automated analyzer for vancomycin in rat plasma by column-switching high-performance liquid chromatography (HPLC) with UV detection was developed. The method includes in-line extraction of vancomycin by ion-exchange cartridge column and a separation on a reversed-phase column with UV detection at 215 nm. Plasma samples were diluted by mobile phase solution and directly injected to HPLC. Vancomycin was quantitatively recovered from rat plasma samples. The separation was completed within 15 min. The calibration curve was linear over the range from 0.5 to 100 microg/mL with the detection and quantification limits of 0.5 microg/mL (2.5 ng on column; signal-to-noise ratio = 3). The values of precision in intra- and inter-day assays (n = 3) were less than 1.92 and 3.69%, respectively. This method does not require time-consuming pre-treatment and is suitable for the routine assay of plasma samples.

Animals↗

PubMed2004

Successful combination therapy with trastuzumab and Paclitaxel for adriamycin- and docetaxel-resistant inflammatory breast cancer.

We present a case of adriamycin-and docetaxel-resistant inflammatory breast cancer (IBC) in which partial response was achieved with combination therapy using trastuzumab and paclitaxel. A 48-year old woman noticed a lump in her right breast. She was diagnosed with IBC and the disease was staged as T4d N1 M0, stage III B. The patient was started on neoadjuvant chemotherapy with adriamycin (50 mg/m2) and docetaxel (60 mg/m2) administered every three weeks. Six courses were performed and the response was evaluated as no change. After one month, contralateral breast swelling indicated bilateral IBC. Bilatera1 mastectomy using the Halsted method was performed. The immunohistochemical results of the Hercep Test was strongly positive (3+). After the mastectomy, right pleural effusion appeared, and cytological examination revealed the cells to be classV(adenocarcinoma). To treat the clinically advanced breast cancer, combination therapy with trastuzumab (initially 4 mg/kg followed by two or more cycles of 2 mg/kg) and paclitaxel (80 mg/m2) were given intravenously every week for eight cycles and then every two weeks thereafter. A total of 32 courses of therapy were performed, the pleural effusion completely disappeared and partial response was maintained for a duration of 482 days. The adverse reactions were mild, and it was possible for her to be treated as an outpatient with high quality of life. This report suggests that weekly combination therapy of trastuzumab and paclitaxel was useful for treatment of adriamycin-and docetaxel-resistant metastatic breast cancer.

Antibodies, Monoclonal↗

PubMed2004

Early cytomegalovirus (CMV) gastrointestinal disease that developed 19 days after bone marrow transplantation, with a high-level of CMV antigenemia, of up to 1120 cells/slide.

We report a 19-year-old male with acute myeloid leukemia who developed an early cytomegalovirus gastrointestinal disease with a high level of cytomegalovirus antigenemia after bone marrow transplantation. He underwent bone marrow transplantation from HLA-matched related donor. He developed acute graft-versus-host disease on day 15, and he immediately went on prednisolone. The graft-versus-host disease disappeared immediately, but he developed a severe epigastralgia on day 23. Although absolute neutrophil count was 0.5 x 10(9)/l, the pp65 cytomegalovirus antigenemia increased up to 1120 cells/slide. The endoscope examination was performed on day 29 and it showed erosive gastritis, and microscopical examination revealed nuclear inclusion bodies and positive cells of cytomegalovirus antigen. Ganciclovir treatment was started, and it continued until negative cytomegalovirus antigenemia was confirmed. He consequently discharged to outpatient without late phase CMV diseases or recurrence of AML. We assessed that the patient had two risk factors. First, he was the cytomegalovirus seropositive patient and received bone marrow from seronegative donor. Second, he was treated with prednisolone for acute graft-versus-host disease. The ganciclovir treatment turned out to be successful, but the cytomegalovirus disease developed too early to start the antigenemia guided preemptive treatment. The high-risk patients could develop the early cytomegalovirus disease even though under the status of myelosuppression after bone marrow transplantation.

Adult↗

PubMed2004

Increased QT dispersion in patients with alcoholic pancreatitis.

OBJECTIVES: Increased dispersion of the QT interval has been proposed to be a novel marker for increased risk of ventricular arrhythmia and sudden cardiac death. This study examined whether QT dispersion is affected in patients with alcoholic pancreatitis. METHODS: We measured the QT interval, corrected QT interval, activation recovery interval, activation time, recovery time, and their respective dispersions in 3 age- and gender-matched groups: patients with alcoholic pancreatitis [age, 58.9 +/- 11.8 years; male/female (M/F), 33/3], patients with alcohol dependence (age, 59.3 +/- 8.9 years; M/F, 33/4), and a healthy control group (age, 55.8 +/- 8.8 years; M/F, 33/3). RESULTS: The QT dispersions in patients with alcoholic pancreatitis (62.4 +/- 19.9 milliseconds; P < 0.001) or alcohol dependence (58.2 +/- 19.6 milliseconds; P < 0.001) were significantly greater than in the control group (41.4 +/- 13.3 milliseconds). Similarly, the corrected QT dispersions in patients with alcoholic pancreatitis (68.5 +/- 22.8 milliseconds; P < 0.001) or alcohol dependence (65.3 +/- 23.6 milliseconds; P < 0.001) were significantly greater than in the control group (42.8 +/- 13.2 milliseconds). Both QT dispersion and QTc dispersion were longer in patients with alcoholic pancreatitis than those with alcohol dependence (P = 0.011 and P = 0.039, respectively). Simple linear regression analysis of the relationship between the RR and QT intervals revealed that the regression lines for patients with alcoholic pancreatitis and alcohol dependence were almost parallel. However, the slope of the regression line for the control group was significantly greater (P < 0.05) than for the other 2 lines. CONCLUSION: The findings demonstrate increased QT and QTc dispersions in patients with either alcoholic pancreatitis or alcohol dependence. The QT dispersion and QTc dispersion were longer in patients with alcoholic pancreatitis than those with alcohol dependence.

Arrhythmias, Cardiac↗

PubMed2004

Multicenter prospective study of interferon alpha versus allogeneic stem cell transplantation for patients with new diagnoses of chronic myelogenous leukemia.

We compared interferon alpha (IFN-alpha) therapy with stem cell transplantation (SCT) for patients with chronic-phase chronic myelogenous leukemia in a multicenter prospective study to investigate the optimal indication and timing of SCT, especially from HLA-matched unrelated donors. Of 257 eligible patients, 145 patients who were younger than 50 years were assigned to the IFN-alpha cohort (n = 87) or the SCT cohort (n = 58), according to family donor availability. In the IFN-alpha cohort, 52 patients received IFN-alpha and chemotherapy (the IFN1 group), and 35 patients received an SCT from an unrelated donor (the U-SCT group). In the SCT cohort, 47 patients received an SCT from a related donor (the R-SCT group). In the IFN1 group, 88% of the patients achieved a complete hematologic response, and 33% achieved a complete cytogenetic response. At a median follow-up period of 53 months, the predicted 6-year survival rate was 72% in the IFN1 group, 81% in the R-SCT group, and 81% in the U-SCT group. When overall survival was evaluated for the IFN-alpha and R-SCT cohorts by intention to treat according to family donor availability, the 6-year survival rates were 76% and 84%, respectively. When the outcomes of the U-SCT and IFN1 groups were compared, the survival rate of U-SCT group patients was significantly better than for IFN1 group patients without a major cytogenetic response and seemed better for IFN1 group patients younger than 35 years. Therefore, U-SCT may be recommendable to patients who fail to achieve a major cytogenetic response in IFN-alpha therapy and to younger patients.

Adult↗

PubMed2004

[Molecular targeted treatment--new treatment strategy for patients with chronic myeloid leukemia].

Imatinib mesylate is a new drug that can inhibit the tyrosine kinase activity of Bcr-Abl, the receptors for platelet-derived growth factor receptor(PDGF) and stem cell factor, or c-kit. Chronic myeloid leukemia (CML) is distinguished by the presence of a reciprocal translocation between chromosomes 9 and 22 that results in a shortened chromosome 22, termed the Philadelphia(Ph) chromosome. As a result of the translocation, a fusion gene called the Bcr-Abl gene is created from two normal cellular genes, encoding a chimeric Bcr-Abl protein with a deregulated tyrosine kinase activity. The expression of Bcr-Abl tyrosine kinase has been shown to be necessary and sufficient for the transformed phenotype of CML cells. Imatinib can block the kinase activity of Bcr-Abl, thus inhibiting the proliferation of Ph-positive progenitors, and has shown activity against all phases of CML, though responses are most substantial and durable in patients in the chronic phase. An international phase III study which compared the efficacy of imatinib with that of interferon alpha combined with low-dose cytarabine in newly diagnosed chronic-phase CML showed the rate of major cytogenetic response at 24 months was 90%, including 82% of complete cytogenetic response. These results indicated that imatinib was superior to interferon-containing treatment as a first-line therapy. More than 10,000 patients worldwide, including those in Japan, have been treated with imatinib in clinical trials, and a lot of information has been accumulated on the use of this drug. The aim of this article is to review the use of this drug and the practical management of patients with chronic myeloid leukemia.

Antineoplastic Agents↗

PubMed2004

[Progressive outer retinal necrosis in a patient with malignant lymphoma].

A 29-year-old man with diffuse large B-cell lymphoma treated by radiotherapy for his relapsed lesion followed by 4 doses of weekly rituximab was admitted to our hospital with interstitial pneumonia. After steroid pulse therapy, he had contraction of the left visual field. He was diagnosed as having progressive outer retinal necrosis due to a varicella-zoster virus that was detected from the left vitreous sample. Systemic antiviral treatment failed to prevent rapid development of whole layer necrosis of the left retina. Vitrectomy with silicone oil tamponade saved his final visual acuity. This unusual event might be related to rituximab causing deterioration of humoral immunity.

Adult↗

PubMed2004

Th1/Th2 lymphocyte balance in patients with aplastic anemia.

Activated T cell plays an important role in the pathogenesis of aplastic anemia (AA). CD4+ T cells are divided into Th1 cells producing hematopoietic inhibitory cytokines like interferon-gamma and Th2 cells producing interleukin-4. We investigated the Th1/Th2 cell ratio in the peripheral blood of AA patients treated with immunosuppressive therapy (IST). There were 10 patients who responded well to IST (responders) and 3 patients who were refractory to IST (non-responders). Th1 cells were lower in responders than in non-responders (16.2+/-2.4% vs. 28.8+/-5.5%, respectively, p<0.05), whereas Th2 cells did not differ. The Th1/Th2 ratio was also significantly lower in responders than in non-responders, being 13.2+/-1.5 and 40.4+/-5.1 (p<0.001), respectively. In three responders, the Th1/Th2 ratio was declined according to the hematological recovery (from 10.6 to 8.3, 16.3 to 10.9 and 11.8 to 9.5). Our results suggest that Th1 lymphocytes are more predominant in AA, and it may be very useful to monitor the Th1/Th2 ratio during IST.

Adult↗

PubMed2003

Antibacterial and antiproliferative activity of cationic fullerene derivatives.

We examined the antibacterial and antiproliferative activities of alkylated C(60)-bis(N,N-dimethylpyrrolidinium iodide) derivatives. The fullerene derivatives inhibited bacteria and cancer cell growth effectively. However, the fullerene derivatives with a long alkyl chain did not show antibacterial activity.

Anti-Bacterial Agents↗

PubMed2003

Respiratory chain inhibition by fullerene derivatives: hydrogen peroxide production caused by fullerene derivatives and a respiratory chain system.

Fullerene is a new type of carbon allotrope. We have shown that the fullerene derivative C(60)-bis(N,N-dimethylpyrrolidinium iodide), a regio isomer mixture, inhibited Escherichia coli growth and dioxygen uptake caused by E. coli and glucose. This result indicates that the mechanism of the bacteriostatic effect is the inhibition of energy metabolism. In this study, we isolated two regio isomers of C(60)-bis(N,N-dimethylpyrrolidinium iodide) and studied their effect on E. coli growth and on respiratory chain activity. In dioxygen uptake caused by the inner-membrane and NADH, the effect of fullerene derivatives was biphasic. At low concentrations of both fullerene derivatives, dioxygen uptake was inhibited, whereas at high concentrations, it was increased. At high concentrations, consumed dioxygen was converted to H(2)O(2). An electrochemical study revealed that reduced fullerene derivatives react with dioxygen. This activity was closely related to a redox property of the isomers.

Catalase↗

PubMed2003

Recent progress in derivatization methods for LC and CE analysis.

The derivatization procedure with a suitable fluorescence or chemiluminescence reagent is performed for the purpose of increasing the detection sensitivity and selectivity, in high-performance liquid chromatography (HPLC) and/or capillary electrophoresis (CE). In this article, recent derivatization methods and their applications to biosamples are described. In HPLC, femto mol order of mass detection limits are obtained by derivatization. Regarding the fluorescence reagents, the use of water-soluble reagents has been effective to avoid an undesired adsorption in the process of determination of peptides. In CE, the advantages of having extremely low mass detection limits (ranging from atto to yocto mol level) and requiring only a very short analysis time (less than a few minutes) are made possible by using laser-induced fluorescence or near infra-red detections.

Chromatography, High Pressure Liquid↗

PubMed2003

[Successful induction of complete cytogenetic response with high-dose imatinib mesylate and subsequent allogeneic stem cell transplantation for CML blastic crisis].

A 29-year-old man was referred to our hospital with leukocytosis on March 7th, 2002. The white blood cell count was 132.9 x 10(3)/microliter with 42.0% blast cells. We diagnosed Philadelphia chromosome-positive chronic myelogenous leukemia (CML) in a blast crisis and started imatinib mesylate therapy at a dose of 800 mg/day on March 9th, 2002. The patient's peripheral blood blasts had disappeared by March 22nd, 2002, and the percentage of blasts in the bone marrow was 0.6% on May 2nd, 2002. The patient achieved a complete cytogenetic response on May 13th, 2002, and underwent allogeneic peripheral blood stem cell transplantation from his HLA-identical sibling donor on May 30th, 2002. Although adverse reactions such as grade 3/4 of hematological events (leukopenia, anemia, thrombocytopenia and neutropenia) and grade 1/2 of non-hematological events (hyperbilirubinemia, dermatitis and edema) were observed, these adverse reactions were clinically managed. This case suggested the usefulness of imatinib mesylate in the management of the CML-associated blast crisis.

Adult↗

PubMed2003

[Simultaneous detection of both non-Hodgkin's lymphoma cells and breast cancer cells in pleural effusion--a case report].

A 55-year-old woman underwent breast-conserving surgery with irradiation for Stage IIB (T2 N1 M0) breast cancer of her right breast. Thereafter, she was treated orally with oral UFT and tamoxifen. Three years following surgery, she was diagnosed as having a non-Hodgkin's lymphoma. She underwent 6 cycles of EPOCH-G (etoposide, vincristine, adriamycin, cyclophosphamide, prednisolone, G-CSF) therapy, and obtained complete remission. Two years later, her neck and inguinal lymph nodes were swollen. Biopsy confirmed the relapse of NHL. She underwent salvage chemotherapies of MST-16, carboplatin, IVAC, and CPT-11, but the disease was refractory. In May 2000, bilateral pleural effusion was detected. Cytomorphologically, the pleural fluid specimen showed both atypical lymphoid cells and adenocarcinoma cells simultaneously. Existence of double cancer in the pleural effusion has not been reported, suggesting that this case is rare.

Adenocarcinoma↗

PubMed2002

Successful immunosuppressive therapy with cyclosporine A for posthepatitis B-cell deficiency with activated cytoplasmic interferon--gamma-positive T-lymphocytes.

We describe a patient with transient disappearance of B-cells, hypogammaglobulinemia, and mild pancytopenia after acute hepatitis. Both HLA-DR+CD8+ and intracellular interferon-gamma+/interleukin-4- cell levels were markedly increased, resulting in an increase in the cytotoxic T-cell (T(C))1/Tc2 and helper T-cell (T(H))1/T(H)2 ratios. After immunosuppressive therapy with cyclosporine A, these parameters of T-cell activation were clearly decreased, and hematologic recovery, including an increase in B-lymphocytes and immunoglobulin concentration, was obtained. These results suggest that there had been suppression of B-cells by activated T-cells. Some patients with common variable immunodeficiency show similar activation of T-cell function, and the present findings suggest the possibility of immunosuppressive therapy for such patients.

Adult↗

PubMed2002

Intensified daunorubicin in induction therapy and autologous peripheral blood stem cell transplantation in postremission therapy (Double-7 protocol) for adult acute myeloid leukemia.

To investigate whether an intensified dose of daunorubicin (DNR) in induction therapy and autologous peripheral blood stem cell transplantation (PBSCT) in the postremission period are effective treatments, we used a Double-7 protocol to treat adult patients with de novo acute myeloid leukemia (excluding M0 and M3). Induction therapy consisted of 40 mg/m2 of DNR intravenous drip infusion for 7 days and 200 mg/m2 of ara-C by continuous infusion for 7 days (7 + 7 DC regimen). Patients who achieved complete remission (CR) were given high-dose chemotherapy with autologous PBSCT in postremission therapy. Of the 22 assessable patients, 16 attained CR (73%). Disease-free survival (DFS) and overall survival (OS) at 3 years were 61.2% and 48.1%, respectively. Nine of the CR patients underwent PBSCT without therapy-related mortality. Patients in a favorable cytogenetic group (n = 7) attained 100% CR and long-term survival (71.4% DFS and 85.7% OS at 3 years). Thus, intensified DNR administration of 280 mg/m2 (40 mg/m2 per day for 7 days) in induction therapy for adult patients younger than 60 years of age might be optimal or at least comparable with the new anthracyclines such as idarubicin. In addition, autologous PBSCT in postremission therapy might improve DFS and OS, at least for patients in a favorable cytogenetic group, such as those with a t(8;21) abnormality.

Acute Disease↗

PubMed2002

Ultrasonographic splanchnic arterial flow measurement in severe acute pancreatitis.

INTRODUCTION: Duplex ultrasonographic technology is now capable of detecting flow signals in the various splanchnic vessels and calculating the concomitant flow velocities using fast-Fourier transformation. AIM: To use Doppler sonography to investigate how splanchnic hemodynamics vary during the early stage of severe acute pancreatitis. METHODOLOGY: Six patients with severe acute pancreatitis (age, 59.0 +/- 6.57 years; four men, two women) and seven with mild to moderate acute pancreatitis (age, 60.1 +/- 7.41 years; five men, two women) were examined with Doppler sonography immediately after disease onset. The maximum velocity, minimum velocity, mean velocity, pulsatility index, and resistive index were determined from the Doppler spectra from the proper hepatic artery, celiac artery, and superior mesenteric artery. We also examined 15 healthy subjects (age, 59.3 +/- 4.60 years; 10 men, five women) as controls. RESULTS: The maximum velocity of the proper hepatic artery in patients with severe acute pancreatitis was significantly higher than that in patients with mild to moderate acute pancreatitis (p = 0.011) and in control subjects (p = 0.0047). Similarly, significant increases in both the minimum velocity and the mean velocity of the proper hepatic artery were observed in patients with severe acute pancreatitis. Neither pulsatility index nor resistive index of the proper hepatic artery showed a significant difference among the three groups. There were no significant differences among the three groups with respect to the flow velocity of the superior mesenteric artery. In contrast, the pulsatility index of the superior mesenteric artery in patients with severe acute pancreatitis was significantly lower than that in patients with mild to moderate acute pancreatitis (p = 0.0058) or in control subjects (p = 0.0024). For patients with acute pancreatitis, a significant inverse correlation was obtained between the maximum velocity of the proper hepatic artery and the pulsatility index of the superior mesenteric artery (r = -0.658, p = 0.0145). CONCLUSION: The increase in the hepatic arterial flow velocity and the decrease in the superior mesenteric arterial pulsatility index may represent early events of the severe type of acute pancreatitis.

Acute Disease↗

PubMed2002

Molecular cloning and characterization of chymopasin, a novel serine protease from rat pancreas.

INTRODUCTION: Pancreas secretes many enzymes for food digestion into the pancreatic juice. We cloned a novel serine protease, chymopasin, from rat pancreas. AIMS: To know the localization of this enzyme in the pancreas and to analyze the enzymatic characteristics. METHODOLOGY: We cloned chymopasin cDNA using 3' and 5' RACEs. Northern blot and in situ hybridization were used to study the expression of this enzyme. Recombinant chymopasin protein produced by was analyzed by Western blot using specific antibody, and its enzymatic characteristics were examined using commercially available synthetic substrates, fibrin and gelatin. RESULTS: The open reading frame of rat chymopasin consisted of 792 bp encoding 264 amino acid residues. The deduced amino acid sequence contained the essential catalytic triad characteristic of the serine protease family. There was no putative N-glycosylation site. The amino acid sequence of rat chymopasin showed 54.5% identity to rat chymotrypsin B. Northern blot analysis showed that the transcript was strongly expressed in the pancreas. In situ hybridization with digoxigenin-labeled cRNA probe showed that the positive signals were observed in the acinar cells, but not in the islet or duct cells. Chymopasin protein was detected in the pancreas homogenate and bile-pancreatic juice. Further, cerulein stimulated the secretion of rat chymopasin into bile-pancreatic juice. CONCLUSION: These results suggested that rat chymopasin might be a digestive enzyme secreted from the acinar cells. From the enzyme assay using synthetic substrates, the purified recombinant chymopasin expressed in showed chymotrypsin-like activity. In addition, rat recombinant chymopasin showed fibrinolytic and gelatinolytic activities. These results suggested a role in the pathogenesis of pancreatic damage.

Amino Acid Sequence↗