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Biomedical subjects

K Niiya

Publications and source records attributed to K Niiya.

At least 37 records · Page 2Linked to original sources

Effects of perilla seed oil supplementation on leukotriene generation by leucocytes in patients with asthma associated with lipometabolism.

BACKGROUND: Dietary sources of alpha-linolenic acid, such as perilla seed oil, may have the capacity to inhibit the generation of leukotrienes (LTs) by leucocytes in patients with asthma, as has been reported with the consumption of other long-chain n-3 fatty acids. METHODS: The factors affecting the suppression of leukotriene (LT) C4 generation by leucocytes were examined by comparing the clinical features of patients with asthma who had been given dietary perilla seed oil (n-3 fatty acids). Group A consisted of patients in whom the leucocyte generation of LTC4 was suppressed by dietary perilla seed oil. Group B consisted of those in whom LTC4 generation was not suppressed. RESULTS: LTC4 generation by leucocytes decreased significantly in group A after 2 (p < 0.05) and 4 weeks (p < 0.05); conversely, it increased significantly in group B after 4 weeks (p < 0.05). The two study groups differed significantly in terms of LTC4 generation by leucocytes after 4 weeks of dietary supplementation (p < 0.05). Ventilatory parameters such as peak expiratory flow (PEF), forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV(1)) increased significantly after 4 weeks of dietary supplementation in group A (p < 0.05). Values of PEF, FVC, FEV(1) and maximum expiratory flow at 25% of the forced vital capacity (V(25)) differed significantly between groups A and B prior to dietary supplementation. Serum levels of total cholesterol, low-density lipoprotein (LDL) cholesterol and phospholipid were significantly decreased by dietary supplementation in group A after 4 weeks. Serum levels of total cholesterol, triglyceride, high-density lipoprotein cholesterol, LDL cholesterol and phospholipid differed significantly between the two study groups prior to dietary supplementation. Serum levels of triglyceride and LDL cholesterol differed significantly between the two study groups after 4 weeks of dietary supplementation. CONCLUSIONS: Dietary supplementation with perilla seed oil in selected patients with asthma suppresses the generation of LTC4 and is associated with clinical features such as respiratory function and lipometabolism.

Adult↗

Granulocyte colony-stimulating factor and lineage-independent modulation of VLA-4 expression on circulating CD34+ cells.

Although the use of allogeneic transplants of peripheral blood stem/progenitor cells (PBSCs) is increasing, the precise mechanism of PBSC mobilization has not yet been fully clarified. We examined the expression of some adhesion molecules on CD34+ cells from steady-state bone marrow (BM), granulocyte colony-stimulating factor (G-CSF)-mobilized PBSCs, and cytotoxic drugs plus G-CSF-mobilized PBSCs. Irrespective of mobilization method, very late antigen (VLA)-4 expression on circulating CD34+ cells was significantly lower than on steady-state BM CD34+ cells. To elucidate the influence of lineage commitment on VLA-4 expression of circulating CD34+ cells, we analyzed VLA-4 expression on different subsets of CD34+ cells with or without CD33, CD38, CD5, or CD10 antigens, or Glycophorin A in G-CSF-mobilized PBSCs and steady-state BM from related donors, using 3-color flow cytometry. VLA-4 on circulating CD34+ subsets was less expressed than on each corresponding subset of steady-state BM CD34+ cells. Furthermore, VLA-4 positive rates showed no significant difference among the CD34+ subsets. Finally, the data comparing CD34+ cells from steady-state and G-CSF-mobilized PBSCs revealed no differences in terms of VLA-4 expression. These data suggest that reduced expression of VLA-4 may be a result of peripheralization of CD34+ cells from bone marrow, which occurs in a G-CSF- and lineage-independent fashion.

Anti-Allergic Agents↗

[Development of factor VIII inhibitor in three non-hemophiliac patients].

Infrequently, inhibitors against factor VIII can develop in non-hemophiliac patients and cause serious bleeding. In the last year, we have experienced 3 non-hemophiliac patients who developed factor VIII inhibitors. Here, we describe the clinical courses of the three patients and the characteristics of the inhibitors. Case 1: A 69-year-old man underwent a partial gastrectomy because of early gastric cancer, and one month later developed signs of a bleeding tendency such as hematemesis, tarry stools and intramuscular hemorrhage. Blood coagulation tests revealed prolongation of the activated partial thromboplastin time (aPTT), which had been normal on admission. Case 2: A 78-year-old woman with no previous disease history developed generalized subcutaneous purpura. Blood coagulation tests performed on admission revealed a prolonged aPTT. Case 3: A 30-year-old man was admitted to an emergency hospital because of left intrapleural hemorrhage and liver injury caused by a traffic accident. Two months later, a hematoma developed at the site of drainage in the left chest, and blood coagulation tests revealed prolongation of the aPTT, which had been normal on admission. Plasma factor VIII procoagulant activities in cases 1, 2 and 3 were 3%, 1% and 5%, respectively. The respective factor VIII inhibitor titers were 78, 870 and 0.5 Bethesda units/ml. The immunoglobulin class and subclass of the inhibitors examined by an ELISA method were: case 1, IgG1 and 4; case 2, IgG2 and 4 (dominant); case 3, IgG4. In cases 1 and 3, the patients recovered after glucocorticoid therapy, but in case 2 the patient died of intraperitoneal hemorrhage despite receiving two courses of methylprednisolone pulse therapy. The above clinical experience suggests that patients, who develop high titers of inhibitors may be refractory to ordinary immunosuppressive therapy, and therefore more aggressive therapy such as plasma exchange and/or bypass therapy using activated prothrombin complex concentrates or an activated factor VII preparation should be considered.

Adult↗

Successful engraftment of allogeneic peripheral blood stem cell transplant after nonmyeloablative preparative regimen with cytarabine and cyclophosphamide: report of 2 cases.

We report our experience with allogeneic peripheral blood stem cell transplantation (allo-PBSCT) following a nonmyeloablative conditioning regimen consisting of cytarabine (8 g/m2) and cyclophosphamide (120 mg/kg) in the treatment of 2 patients aged 50 and 55 years with refractory chronic myelomonocytic leukemia and chronic myeloid leukemia in accelerated phase, respectively. Our nonmyeloablative regimen was well tolerated by older patients at high risk of regimen-related toxicity by the conventional conditioning regimen but was immunosuppressive enough to achieve mixed chimerism. After allo-PBSCT, we monitored chimerism in these patients by fluorescence in situ hybridization using X- and Y-specific probes and polymerase chain reaction-based analysis of a variable number of tandem repeats. We found that full chimerism and graft-versus-leukemia (GVL) effects could be induced in these patients by donor lymphocyte infusions and withdrawal of posttransplantation immunosuppressive therapy. Our observations suggest that a nonmyeloablative conditioning regimen can establish mixed chimerism and that donor lymphocyte infusion may induce GVL effects in older patients at high risk of regimen-related toxicity.

Cyclophosphamide↗

Transient factor VIII inhibitor in a hemophilia patient after staphylococcal septic shock syndrome.

We report a transient type I factor VIII inhibitor that arose in a 30-year-old hemophilia patient just after staphylococcal septicemia. This situation usually occurs early in the course of substitution therapy with factor VIII concentrate in hemophilia patients. Although disseminated intravascular coagulation and acute respiratory distress syndrome developed after septic shock, the patient recovered following intravenous administration of antibiotics (meropenem and gentamycin), an antithrombin preparation, high-dose methylprednisolone, and recombinant factor VIII concentrate (rFVIII). During this therapy, however, activated partial thromboplastin time gradually lengthened. On the seventh day of hospitalization, intracranial hemorrhage occurred with right hemiplegia, even though the substitution therapy had continued at the same dosage (30 U/kg per day) of rFVIII. At that point, 4 Bethesda units of the type I inhibitor against factor VIII were detected in the plasma. Increased amounts (46 U/kg per day) of rFVIII and prednisolone were administered, and hypothermic therapy was initiated. Following these treatments, the patient's general condition gradually improved, and within 25 days the inhibitor titer dropped to undetectable levels and did not recur during treatment. These clinical findings suggest that the staphylococcal septic shock may have acted as a trigger in the development of transient factor VIII inhibitor in this patient.

Adult↗

Nutritional therapy of chronic hepatitis by whey protein (non-heated).

In an open study the clinical efficacy of milk serum (whey) protein (Immunocal; cysteine content: 7.6-fold higher than that of casein) isolated from fresh milk and purified without heating was evaluated in 25 patients with chronic hepatitis B or C. Immunocal (12 g as protein) food (mousse) was given twice a day, in the morning and evening, for 12 weeks (test period). Casein (12 g as protein) food (mousse) was similarly given for two weeks prior to the start of the supplement with Immunocal food (induction period) and for four weeks after the end of the supplement with Immunocal food (follow-up period). Serum alanine aminotransferase (ALT) activity was reduced, and plasma glutathione (GSH) levels increased in six and five of eight patients with chronic hepatitis B, respectively, 12 weeks after the start of the supplement with Immunocal food. Serum lipid peroxide levels significantly decreased, and interleukin (IL)-2 levels and natural killer (NK) activity significantly increased. However, there were no significant Immunocal-related changes in 17 patients with chronic hepatitis C. These findings suggest that the long-term supplement with Immunocal alone may be effective for improving liver dysfunctions in patients with chronic hepatitis B.

Adult↗

Molecular characterization of total kininogen deficiency in Japanese patients.

Kininogens are multifunctional plasma glycoproteins. There are two forms of human kininogen: low molecular weight kininogen (LK) and high molecular weight kininogen (HK). Both are derived from the same gene by alternative splicing. Some patients with kininogen deficiency have been reported to be deficient only in HK while others are deficient in both HK and LK (total kininogen deficiency). We analyzed three Japanese patients with total kininogen deficiency by the Csp45I digestion study of exon 5 as previously reported in Williams trait and found that two had the same point mutation of C to T at base 22 of exon 5, resulting in a transition of CGA (Arg) codon to TGA (Stop) codon. This is the first report of molecular characterization of total kininogen deficiency in the Japanese population.

Codon↗

Monitoring of human herpesviruses after allogeneic peripheral blood stem cell transplantation and bone marrow transplantation.

Herpesviruses frequently cause serious complications after allogeneic bone marrow transplantation (allo-BMT). Recent studies have shown more rapid immune reconstitution after allogeneic peripheral blood stem cell transplantation (allo-PBSCT) compared with allo-BMT. However, it has not been clarified whether the improved immune reconstitution after allo-PBSCT is associated with a lower incidence of herpesvirus infections. We monitored the emergence of Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpesvirus 6 (HHV-6) and HHV-7 DNA by a nested-double polymerase chain reaction in peripheral blood leucocytes from 22 allo-BMT and 16 allo-PBSCT patients. Each virus had an unique temporal profile of detection. HHV-6 DNA was detected most frequently at 3 weeks after transplantation, whereas CMV and EBV DNA were detected later (2-3 months). Detection rates of HHV-6 DNA at 3 and 4 weeks after allo-BMT were significantly higher than those after allo-PBSCT (9/16 v 2/13 at 3 weeks, P < 0.01; 10/21 v 1/15 at 4 weeks, P < 0.01). Detection rates of the other three herpesviruses after the two types of allogeneic transplantation were not significantly different throughout observation period. Furthermore, detection of HHV-6 DNA within the first 4 weeks was associated with delayed platelet engraftment after both allo-BMT and allo-PBSCT (P < 0.01). These results suggest an advantage for allo-PBSCT over allo-BMT in terms of suppression of HHV-6 reactivation and prevention of subsequent complications.

Adolescent↗

Analysis of circulating hematopoietic progenitor cells after peripheral blood stem cell transplantation.

We investigated the kinetics of posttransplant circulating progenitor cells (PTCPC) in the early phase after autologous (auto-) and allogeneic (allo-) peripheral blood stem cell transplantation (PBSCT). We analyzed the number of myeloid progenitor cells (CFU-GM) per 10 ml of peripheral blood (PB) on days 0 (just prior to transplantation), 1 (12-15 hours after completion of first transplantation), 2, 3, 5, 7, 10, 14, 17, 21 and 28 (after auto-PBSCT), and also additionally on day 35 after allo-PBSCT. A standard methylcellulose colony assay was used for analysing the number of CFU-GGM and BFU-E on all of the days. In addition, high proliferative potential-colony forming cells (HPP-CFC) of the harvested PBSC from donors and day 1 PB from recipients were assayed in 5 allo-PBSCT patients. Furthermore, a proportion of CD38- cells among CD34+ cells in the harvested PBSC and day 1 PB was evaluated by two-color flow cytometric analysis in 5 allo-PBSCT patients. The number of CFU-GM on day 1 ranged from 7 to 119 per 10 ml PB after auto-PBSCT, and from 15 to 61 per 10 ml PB after allo-PBSCT. After these transient increases, PTCPC diminished rapidly. Then, PTCPC emerged again on day 7 after auto-PBSCT and on day 10 or 14 after allo-PBSCT along with neutrophil recovery. A proportion of HPP-CFC among myeloid colonies from day 1 PB of recipients was significantly higher than that from the harvested PBSC from donors (65.6 +/- 12.7% vs. 17.4 +/- 13.0%, respectively, n = 5, P = 0.0013). In addition, two-color flow cytometric analysis revealed that the proportion of CD34+CD38- cells was significantly higher in day 1 PB of recipients than in the harvested PBSC from donors (57.5 +/- 17.6% vs. 11.7 +/- 4.9%, n = 5, P = 0.005). These observations suggest that both primitive and committed transplanted myeloid progenitor cells may circulate in the very early period following PBSCT.

Adult↗

Factor VII Morioka (FVII L-26P): a homozygous missense mutation in the signal sequence identified in a patient with factor VII deficiency.

We investigated the molecular basis of factor VII deficiency in a Japanese patient and identified a novel missense mutation in the signal sequence of the gene. Factor VII activity and antigen level measured in the patient were 10.7% and 11% of normal, respectively. All exons except 1B and the 5'-flanking region containing promoter region were amplified by polymerase chain reaction (PCR) from genomic DNA. Sequencing analysis of the PCR fragments revealed that the patient was a homozygote for a T to C substitution at nucleotide position 38. This mutation predicts an amino acid replacement of leucine to proline at codon -26 in the hydrophobic core of the signal peptide, which probably affects translocation of the protein into endoplasmic reticulum and subsequently causes reduction in plasma factor VII level.

Aged↗

Transcriptional regulation of urokinase-type plasminogen activator receptor by cyclic AMP in PL-21 human myeloid leukemia cells: comparison with the regulation by phorbol myristate acetate.

We investigated the effect of dibutyryl cyclic AMP (Bt2-cAMP) on urokinase-type plasminogen activator receptor (uPAR) expression in human PL-21 myeloid leukemia cells and compared it with the effect of phorbol myristate acetate (PMA). Flow cytometric analysis clearly demonstrated that Bt2-cAMP and PMA both induced the cell surface expression of uPAR. Northern analysis and nuclear run-on assay revealed that cAMP and PMA activated the uPAR gene transcription and both additively increased the uPAR mRNA level. However, actinomycin-D decay experiment showed that PMA, but not cAMP, prolonged the uPAR mRNA half-life. Furthermore, inhibition of the ongoing protein synthesis with cycloheximide abrogated completely the PMA-induced uPAR mRNA accumulation but only partially the induction by PMA plus cAMP, whereas the induction by cAMP alone was rather amplified, indicating that the de novo protein synthesis is necessary in the induction by PMA but not in the induction by cAMP and that the cAMP pathway may be dominant in uPAR gene expression in the PL-21 cells as compared to the PMA pathway. These results suggest that cAMP induces the uPAR expression exclusively through activating the gene transcription in which a preexisting transcriptional factor may be involved, whereas PMA transcriptionally and posttranscriptionally regulates the uPAR gene expression.

Carcinogens↗

[Inter-institute variations in International Normalized Ratio and thrombotest].

Oral anticoagulant therapy is effective for reducing the risk of thromboembolic events in patients with atrial fibrillation or other heart diseases. However, the intensity of oral anticoagulation therapy required in high risk patients, especially in Japanese patients, to achieve the best balance between the prevention of thromboembolic events and bleeding complications remains unclear. The multicenter study of Toyama Warfarin Rational Dosage (TOWARD) was started in 1996 to determine the optimal level of anticoagulant therapy. This study investigated the relationship between values of thrombotest (TT) and International Normalized Ratio (INR) measured from the same samples to clarify inter-institute variations. The relationship between TT and INR was not linear but hyperbolic. Changes of INR to TT are relatively small in the TT range of more than 20% as compared with the range of 20% or less. There were considerable inter-institute variations of TT, and the coefficient of variation (CV) was 0.16 and 0.24 in the low level and high level anticoagulation samples, respectively. However, the variations became significantly small when the same reference was used. The CV of INR was 0.12 and 0.08 in the high level and low level anticoagulation samples, respectively, and very similar with the control samples without anticoagulation (0.11). The variation was small when INR was obtained from the international sensitivity index (ISI) of thromboplastin less than 1.5. TT is widely used for monitoring oral anticoagulant therapy in Japan, and is an excellent system with little inter-institute variation when a standard reference is offered. Since INR has been established as an international monitoring system, the use of INR measured with thromboplastin of small ISI is recommended for monitoring.

Anticoagulants↗

Calcium spirulan as an inducer of tissue-type plasminogen activator in human fetal lung fibroblasts.

Calcium spirulan (Ca-SP), a novel sulfated polysaccharide isolated from the blue-green alga Spirulina platensis, has been found to have antiviral and heparin cofactor II-dependent antithrombin activities. We have obtained evidence that Ca-SP is a potent inducer of tissue-type plasminogen activator (t-PA) production. The addition of Ca-SP to a culture of IMR-90 human fetal lung fibroblasts increased t-PA concentrations in the conditioned medium, in a dose- and time-dependent manner, but in the cell lysate, t-PA concentrations were unchanged, suggesting that t-PA induced by Ca-SP is easily secreted into the conditioned medium. The amount of newly synthesized t-PA in IMR-90 cells, as measured by labeling with [35S]methionine and subsequent immunoprecipitation of t-PA from conditioned medium, was significantly increased by Ca-SP-stimulation. However, Ca-SP did not increase the t-PA mRNA levels. As previously reported, thrombin stimulated t-PA gene transcription in IMR-90 cells, and the simultaneous treatment with Ca-SP and thrombin caused further enhancement of t-PA production, in a synergistic manner. It would thus appear that Ca-SP increases t-PA production through post-transcriptional processes. IMR-90 cells also produce plasminogen activator inhibitor type-1 (PAI-1), but Ca-SP showed little effect on the PAI-1 production. H-SP, which was obtained by removing the calcium from Ca-SP, had no effect on the t-PA production. Na-SP, which was prepared by replacement of the calcium with sodium, stimulated the t-PA production similarly to Ca-SP. Thus, Ca-SP specifically induces t-PA production, and the molecular conformation of Ca-SP maintained by Ca or Na may be essential for the stimulation of t-PA synthesis.

Blotting, Northern↗

[A comparative study of the ELISA and IF methods for antinuclear antibody test].

A new ELISA method for antinuclear antibody(ANA) test was investigated for its clinical usefulness by comparison with a widely used IF method. Both methods used Hep 2 cells as a substrate. ELISA method showed good reproducibility in both within-run(CV = 5.1 approximately 8.7%) and between-run(CV = 8.1 approximately 9.6%) assays. ROC analysis revealed that ELISA method had a higher sensitivity and an equal specificity as compared to IF method. Application of an auto analyzing system to ELISA method could induce the improvement of efficacy and labor saving. The coincidence rate between ELISA and IF methods was 78.6% on the samples from 887 patients with various disorders. In patients with drug induced lupus or connective tissue diseases except for rheumatoid arthritis, the discrepancies were caused mainly by the higher sensitivity of ELISA method. However, the ELISA test was less sensitive for the ANAs showing granular, nuclear membrane, or anti-PCNA antibody like staining patterns by IF method. In conclusion, ELISA method is useful for detecting ANAs because of its high sensitivity and efficiency, though it still has some points to be improved.

Antibodies, Antinuclear↗