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Yoshihisa Nojima

Publications and source records attributed to Yoshihisa Nojima.

At least 19 recordsLinked to original sources
PubMed2005

Distinctive immunoglobulin VH gene usage in Japanese patients with chronic lymphocytic leukemia.

The incidence of chronic lymphocytic leukemia (CLL) is low in Asian countries including Japan, while CLL is the most common type of leukemia in the west. To elucidate which factors contribute to the low frequency of CLL in Japan, we investigated immunoglobulin (Ig) heavy chain gene usage and somatic hypermutation status in 44 Japanese patients with CLL. Only one of these patients used V(H)1-69. The finding is in striking contrast to data from western countries, where the frequency of CLL expressing V(H)1-69 ranges from 12 to 21%.

Adult↗
PubMed2005

SHPS-1 promotes the survival of circulating erythrocytes through inhibition of phagocytosis by splenic macrophages.

The lifespan of circulating red blood cells (RBCs) produced in bone marrow is determined by their elimination through phagocytosis by splenic macrophages. The mechanism by which RBC elimination is regulated has remained unclear, however. The surface glycoprotein SHPS-1, a member of the immunoglobulin superfamily, is abundant in macrophages. We have now examined the regulation of RBC turnover with the use of mice that express a mutant form of SHPS-1 lacking most of its cytoplasmic region. The mutant mice manifested mild anemia as well as splenomegaly characterized by expansion of the red pulp. The numbers of erythroid precursor cells in the spleen and of circulating reticulocytes were also increased in the mutant mice. In contrast, the half-life of circulating RBCs was reduced in these animals, and the rate of clearance of injected opsonized RBCs from the peripheral circulation was increased in association with their incorporation into splenic macrophages. Phagocytosis of opsonized RBCs by splenic macrophages from mutant mice in vitro was also increased compared with that observed with wild-type macrophages. These results suggest that SHPS-1 negatively regulates the phagocytosis of RBCs by splenic macrophages, thereby determining both the lifespan of individual RBCs and the number of circulating erythrocytes.

Anemia↗
PubMed2005

Involvement of renal progenitor tubular cells in epithelial-to-mesenchymal transition in fibrotic rat kidneys.

Renal progenitor tubular cells (label-retaining cells [LRC]) were recently identified in normal kidneys by in vivo bromodeoxyuridine (BrdU) labeling. This study was conducted to examine the behavior of LRC in renal fibrosis. BrdU was injected intraperitoneally into normal rats daily for 7 d. After a 2-wk chase period, unilateral ureteral obstruction (UUO) was induced in these rats. In normal and contralateral kidneys, LRC were observed scattering among tubular epithelial cells. After UUO, the number of the LRC significantly increased, and most of them were positive for proliferating cell nuclear antigen (PCNA). In contrast, PCNA+ cells lacking BrdU label were rarely observed. It is interesting that LRC were detected not only in tubules but also in the interstitium after UUO. Laminin staining showed that a number of the LRC were adjacent to the destroyed tubular basement membrane. Some tubules, including LRC, lost the expression of E-cadherin after UUO. A large number of cell populations expressed vimentin, heat shock protein 47, or alpha-smooth muscle actin in the UUO kidneys, and each population contained LRC. None of the LRC was positive for these fibroblastic markers in contralateral kidneys. When renal tubules from BrdU-treated rats were cultured in the gel, some cells protruded from the periphery of the tubules and migrated into the gel. Most of these cells were BrdU+. Neither the total content of BrdU in the kidneys nor the number of LRC in bone marrow significantly changed after UUO. Collectively, these results suggest that LRC is a cell population that proliferates, migrates, and transdifferentiates into fibroblast-like cells during renal fibrosis.

Animals↗
PubMed2005

Secretion of parathyroid hormone oscillates depending on the change in serum ionized calcium during hemodialysis and may affect bone metabolism.

BACKGROUND: The current study was undertaken to clarify the dynamic response of parathyroid hormone (PTH) during hemodialysis and to determine whether or not such dynamic change of PTH affects bone turnover. METHODS: Serum ionized calcium (iCa) and intact PTH (iPTH) were measured in 66 dialysis patients before (basal) and after each hemodialysis. The changes of iCa (DeltaiCa) and iPTH (DeltaiPTH) were defined as [postdialysis iCa -basal iCa] mM, and [(postdialysis iPTH - basal iPTH)/basal iPTH] x 100%, respectively. We also investigated the data of the patients divided into four groups based on their basal iPTH levels; group 1 (iPTH < 60 pg/ml, n = 17), 2 (> or = 60 to < 150, n = 20), 3 (> or = 150 to < 300, n = 15), and 4 (> or = 300, n = 14). RESULTS: While iCa and iPTH changed variably during each hemodialysis procedure, there was a highly significant inverse correlation between DeltaiCa and DeltaiPTH (r = -0.761, p < 0.0001). Regression coefficients between DeltaiPTH and DeltaiCa were -519.1, -311.2, -268.1, and -194.6%/mM in groups 1-4, respectively. The difference in the regression coefficient was statistically significant between group 1 and 2 (F = 3.69, p < 0.05, ANCOVA), group 1 and 3 (F = 5.599, p < 0.05), and group 1 and 4 (F = 10.853, p < 0.005). This suggested that patients with higher basal iPTH responded poorly to modulate serum PTH levels by sensing the change of iCa. However, after an intensified oral calcitriol therapy to reduce iPTH, the PTH response in group 4 patients was restored to levels comparable with those observed in patients having lower basal iPTH. We also demonstrate that the DeltaiPTH of patients of group 1 but not of other groups was significantly correlated with serum markers for bone metabolism; osteocalcin (r = 0.535, p < 0.05) and collagen type I C-terminal telopeptide (r = -0.575, p < 0.05). CONCLUSIONS: Our findings suggest that secretion of PTH is dynamically regulated by DeltaiCa during hemodialysis and such oscillated PTH secretion may affect bone metabolism in a subset of dialysis patients.

Adult↗
PubMed2005

Long-term persistence of host cells detected by X-chromosome gene-based assay in patients undergoing gender-mismatched hematopoietic stem cell transplantation.

Using our recently developed human androgen receptor (HUMARA) gene-based chimerism assay, long-term chimerism was investigated in female patients who underwent hematopoietic stem cell transplantation (HCT) with cells from male donors. After restriction digestion of samples, we detected a small number of female-derived cells within a large population of male-derived cells, with a sensitivity from 0.1% to 0.05%. Chimerism was examined in four patients with myeloid malignancies: two patients with acute myeloid leukemia (AML) from myelodysplastic syndrome (MDS), and one patient each with AML M3 and AML M4. All patients underwent myeloablative conditioning regimens and exhibited good clinical results during a median follow-up period of 6.6 years (range, 3.4-7.5 years). Female-derived cells were detected throughout the entire follow-up period in all bone marrow samples, but they became undetectable in the peripheral blood samples of 3 patients. Moreover, the HUMARA band pattern suggests that these residual host cells were normal cells. This study confirms the usefulness of the HUMARA gene-based assay, which showed that patients undergoing HCT frequently show mixed chimerism (MC) for a long period, especially in bone marrow, although the possibility of contamination by host stromal cells cannot be excluded.

Adult↗
PubMed2005

Expression of interleukin-22 in rheumatoid arthritis: potential role as a proinflammatory cytokine.

OBJECTIVE: Interleukin-22 (IL-22) is a novel cytokine of the IL-10 family. Although its pathophysiologic function is largely unknown, induction of acute-phase responses by IL-22 has suggested proinflammatory properties. In this study, we sought to examine whether IL-22 plays a role in the pathogenesis of rheumatoid arthritis (RA). METHODS: Expression of IL-22 and IL-22 receptor 1 (IL-22R1) was examined by reverse transcription-polymerase chain reaction (RT-PCR), Western blot, and immunohistochemical analysis. The effects of recombinant IL-22 (rIL-22) on cultured synovial fibroblasts derived from RA patients (RASF), with regard to the proliferation of synovial fibroblasts and production of monocyte chemoattractant protein 1 (MCP-1), were examined by alamer blue assay and enzyme-linked immunosorbent assay, respectively. RESULTS: IL-22 messenger RNA was detected by RT-PCR in RA synovial tissues and mononuclear cells isolated from RA synovial fluid samples. High levels of IL-22 were expressed both in the lining and the sublining layers of RA synovial tissues. Staining for vimentin and CD68, as markers of synovial fibroblasts and macrophages, respectively, showed that the majority of IL-22-positive cells were synovial fibroblasts and macrophages. IL-22R1 was also expressed in both the lining and the sublining layers of RA synovial tissues. The majority of cells expressing IL-22R1 were positive for vimentin, but not for CD68. Expression of IL-22 and IL-22R1 in RASF was confirmed by RT-PCR and Western blot analysis. In vitro, rIL-22 significantly increased proliferation of RASF and production of MCP-1 by RASF above the value of medium controls. Moreover, MAPK activation was induced in RASF in response to IL-22 stimulation. CONCLUSION: These data suggest that IL-22, produced by synovial fibroblasts and macrophages, promotes inflammatory responses in RA synovial tissues by inducing the proliferation and chemokine production of synovial fibroblasts.

Animals↗
PubMed2005

Comparison of the efficacy of an oral calcitriol pulse or intravenous 22-oxacalcitriol therapies in chronic hemodialysis patients.

BACKGROUND: 1,25-dihydroxy-22-ovavitamin D(3) (22-oxacalcitriol, OCT) was recently introduced commercially as an analogue of 1,25 (OH)(2) vitamin D(3), but one which has less pronounced calcemic activity. METHODS: To examine the efficacy and tolerability of OCT, 46 hemodialysis patients with secondary hyperparathyroidism were randomly assigned to receive either intravenous OCT or oral calcitriol pulse therapies. The patients were monitored for serum calcium, phosphate, intact parathyroid hormone (PTH), and bone alkaline phosphatase (BAP) for 24 weeks. The efficacy of intravenous OCT was also examined in 24 additional patients who were refractory to oral calcitriol pulse therapy. RESULTS: In the randomized trial, intact PTH levels were significantly suppressed within 4 weeks after the initiation of each therapy, and this effect was well maintained thereafter in both treatment groups. While intact PTH was significantly lower at 4 weeks in the calcitriol pulse group than in the OCT group (P = 0.02), no statistical differences were observed during later treatment periods. BAP was reduced equally by each treatment. At 4 weeks (P = 0.02) and thereafter (P = 0.06), serum calcium was higher among calcitriol-treated patients than among those who received OCT treatment. Eight of 24 patients who were refractory to oral calcitriol pulse therapy responded to intravenous OCT. The patients who responded tended to have lower serum intact PTH and phosphorus levels and smaller parathyroid glands at the start of OCT treatment than nonresponders. CONCLUSIONS: OCT is as effective as oral calcitriol pulse therapy in suppressing intact PTH and BAP in chronic hemodialysis patients. It was confirmed that OCT exhibits less calcemic activity than calcitriol. Moreover, under certain conditions, switching to OCT may help in the treatment of hyperparathyroidism, which is refractory to conventional oral calcitriol pulse therapy.

Administration, Oral↗
PubMed2005

High Th1/Th2 ratio in patients with multiple myeloma.

To determine the clinical significance of the T helper 1(Th1)/T helper 2 (Th2) ratio in multiple myeloma, the intracellular IFN-gamma and IL-4 were analyzed by flow cytometry in 56 patients with multiple myeloma. The mean Th1/Th2 ratio of cases in the initial diagnosis phase and the refractory phase were higher than that of the control group. The mean serum beta-2-microglobulin in the high Th1/Th2 subgroup was significantly higher than that in the normal Th1/Th2 subgroup (P < 0.05). In conclusion, the Th1/Th2 ratio was closely related to the disease status of multiple myeloma.

Adult↗
PubMed2005

Impact of brachial-ankle pulse wave velocity and ankle-brachial blood pressure index on mortality in hemodialysis patients.

BACKGROUND: Pulse wave velocity (PWV) and ankle-brachial blood pressure index (ABPI) are markers for atherosclerosis, and each predicts mortality in patients undergoing hemodialysis. However, there have been no studies in the past that compared head-to-head the clinical validity of these 2 parameters. Compared with conventional aortic PWV, brachial-ankle PWV (baPWV) is considered simple and thereby easily applicable to clinical use. METHODS: To clarify the relationship between baPWV and ABPI and assess their prognostic values, we analyzed 785 hemodialysis patients with a mean age of 60.2 +/- 12.5 (SD) years for whom ABPI and baPWV at baseline had been measured simultaneously and who were followed up for 33.8 +/- 10.8 months. RESULTS: Of 785 patients, 131 deaths were recorded. In Kaplan-Meier analysis, all-cause mortality was progressively and significantly greater from the lowest quartile of baPWV onward (log-rank test, 41.8; P < 0.001). However, in Cox proportional hazards analysis, the impact of baPWV was insignificant when ABPI was included as a covariate. ABPI maintained strong predictive power in this model. When patients who had advanced peripheral arterial occlusive disease (ABPI < 0.9) were excluded from analysis, patients with the highest quartile of baPWV had significantly increased hazard ratios of all-cause (hazard ratio, 4.08; 95% confidence interval, 1.46 to 11.43; P < 0.007) and cardiovascular (hazard ratio, 7.03; 95% confidence interval, 1.49 to 33.08; P < 0.014) mortality. The predictive power of baPWV in this population was independent from other covariates associated with atherosclerotic disorders. CONCLUSION: In a head-to-head comparison, ABPI, but not baPWV, showed strong power in predicting the mortality of hemodialysis patients. However, baPWV was useful to pick a high-risk population in patients with ABPI greater than 0.9. Thus, screening hemodialysis patients by means of baPWV and ABPI provides complementary information in identifying a high-risk population.

Adult↗
PubMed2005

Oxidative stress-dependent conversion of hydrogen sulfide to sulfite by activated neutrophils.

Sulfite, which is known as a major constituent of volcanic gas, is endogenously produced in mammals, and its concentration in serum is increased in patients with pneumonia. It has been reported that sulfite is produced by oxidation from hydrogen sulfide (H2S) as an intermediate in the mammalian body. The objective of this study was to investigate the ability of reactive oxygen species from neutrophils to produce sulfite from H2S. Sulfite production from activated neutrophils stimulated with N-formyl-methionyl-leucyl-phenylalanine gradually increased with an increased concentration of sodium hydrosulfide (NaHS) in the medium. The production of sulfite was markedly suppressed with an NADPH oxidase inhibitor, diphenyleneiodonium. When NaHS was added to the supernatant of activated neutrophils, a significant amount of sulfite was synthesized in the test tubes. Furthermore, when a medium containing NaHS was incubated with a water-soluble radical initiator, 2,2'-azobis-(amidinopropane) dihydrochloride, sulfite was formed in the solution and this increase was markedly suppressed by ascorbic acid. Finally, we determined serum concentrations of sulfite and H2S in an in vivo model of neutrophil activation induced by systemic injection of lipopolysaccharide (LPS) into rats. We found a significant increase in serum sulfite and H2S after LPS injection. Importantly, coadministration of ascorbic acid with LPS further increased serum H2S but suppressed sulfite levels. This finding implies that oxidative stress-dependent conversion of H2S to sulfite might occur in vivo. Thus, the oxidation of H2S is a novel sulfite production pathway in the inflammatory condition, and this chemical synthesis might be responsible for the upregulation of sulfite production in inflammatory conditions such as pneumonia.

Animals↗
PubMed2005

Pericardial graft vs. host disease in a patient with myelodysplastic syndrome following peripheral blood stem cell transplantation.

A patient with myelodysplastic syndrome developed pericardial effusion 20 month after allogenic peripheral blood stem cell transplantation. Sclerotic and erythematous skin lesions were observed over the face and extremities, and a diagnosis of chronic graft vs. host disease (GVHD) was made based on skin biopsy findings. Pericardial fluid contained numerous CD8+/HLA-DR+ lymphocytes, but no leukaemic cells. Tumour necrosis factor alpha (TNFalpha) and soluble Fas (sFas) levels were highly elevated in both the effusion and serum. The patient was treated with methylprednisolone and tacrolimus. Skin GVHD improved rapidly associated with resolution of pericardial effusion and reductions in cytokine levels. We concluded that pericardial effusion was due to pericarditis and was a manifestation of chronic GVHD in this patient, and that cytotoxic lymphocytes and specific cytokines played significant roles.

Adult↗
PubMed2005

Methylation status of fragile histidine triad (FHIT) gene and its clinical impact on prognosis of patients with multiple myeloma.

Aberrant methylation of tumor suppressor genes (TSG) has been studied in multiple myeloma (MM). We determined the methylation status of the FHIT (fragile histidine triad) gene, a putative TSG, in 48 patients with MM. Clinical association with its methylation status was then analyzed. The FHIT gene methylation was observed in 21 of the 48 patients (44%). No association between FHIT gene methylation and clinical variables such as age, gender and clinical stage was found. However, the estimated 50% survival time of the methylated group was significantly shorter than that of the unmethylated group (18.2 vs. 45.1 months, P < 0.05). Univariate analysis revealed adverse prognostic factors: FHIT gene methylation (P = 0.028), poor performance status (I to IV, P = 0.002), anemia (< or =8.5 g/dL, P = 0.007), hypoalbuminemia (< or =3.5 g/dL, P < 0.002), high serum C-reactive protein levels (>0.5 mg/dL, P = 0.002), elevated beta-2-microglobulin serum levels (>6.5 mg/L, P < 0.001), and treatments not including autologous peripheral blood stem cell transplantation (auto-PBSCT) (P = 0.007). Multivariate analysis identified FHIT gene methylation [hazard ratio (HR) 1.722, 95% confidence interval (CI) 1.150-2.603, P = 0.009], elevated beta-2-microglobulin serum levels (>6.5 mg/L, HR 2.005, 95% CI 1.035-3.937, P = 0.004), and treatments not including auto-PBSCT are independent predictive variables. These findings indicate that aberrant methylation of the FHIT gene is an independent adverse prognostic factor in MM.

Acid Anhydride Hydrolases↗
PubMed2005

Thiopurine methyltransferase genotype and phenotype status in Japanese patients with systemic lupus erythematosus.

We investigated the genotypic status of thiopurine methyltransferase (TPMT) polymorphism to evaluate the possible risk of the toxicity of azathioprine (AZA) in 68 patients with systemic lupus erythematosus (SLE). The allele frequency of TPMT mutation in the SLE group (2.9%) was higher than that in 174 Japanese healthy volunteers (1.1%), although it did not reach statistically significant difference (p=0.23). The mean value of TPMT activities in 51 subjects with TPMT*1/*1 was 40% higher than that of 4 subjects with TPMT*1/*3C in SLE group (18.1+/-6.1 nmol/h/ml packed red blood cells (pRBC) versus 13.2+/-3.2 nmol/h/ml pRBC; p=0.11). Two out of 4 SLE patients with TPMT*1/*3C had been treated with AZA, and one patient showed a leucopenia. The TPMT genotyping before AZA treatment is recommended for Japanese SLE patient group to avoid the AZA-induced adverse events, although detection of the patient with low TPMT activity by genotyping is still imperfect.

Adolescent↗
PubMed2005

Genotyping of thiopurine methyltransferase using pyrosequencing.

Thiopurine methyltransferase (TPMT) metabolizes thiopurine drugs which are used in the treatment of leukemia and some autoimmune diseases. Previously, 11 mutant alleles of TPMT gene (TPMT*1S, *2, *3A, *3B, *3C, *3D, *4, *5, *6, *7, and *8) have been reported. These mutant alleles may cause life-threatening toxicity in patients exposed to thiopurine drugs, 6-mercaptopurine and azathioprine. We have developed a rapid and accurate protocol for TPMT genotype determination using Pyrosequencing(TM) technology in 96 Japanese subjects. Five fragments of the TPMT gene (exon 4, 5, 7, 8, 10) were amplified by PCR, and the 10 single-nucleotide polymorphisms (SNPs) for TPMT*1S, *2, *3A, *3B, *3C, *3D, *4, *5, *6, *7, and *8 were sequenced. The results of this pyrosequencing method corresponded exactly with those of the DNA sequencing method using BigDye terminator chemistry. We have demonstrated that typing of 10 SNPs can be performed within 30 min. Pyrosequencing has a wide application in the large-scale identification of individual TPMT genotypes.

Adult↗
PubMed2005

X-linked lymphoproliferative disease in an adult.

X-linked lymphoproliferative disease (XLP) is an inherited immunodeficiency characterized by an extreme susceptibility to Epstein-Barr virus (EBV) infection. Patients with XLP mainly present with the 3 clinical manifestations of fulminant infectious mononucleosis, lymphoproliferative disorder, and dysgammaglobulinemia and in rare cases have aplastic anemia and lymphocytic vasculitis. The causative gene for XLP was identified as SH2D1A/DSHP/SLAM-associated protein (SAP) in 1998, and genetic analysis has been used for the definite diagnosis of XLP. Diagnosis for most patients occurs at ages younger than 10 years, and there are few adult patients. Here we describe a 23-year-old man with hypogammaglobulinemia and EBV-associated hemophagocytic lymphohistiocytosis and a diagnosis of XLP. In addition, the patient showed type 1 helper T-cell (Th1) skewing, as has been described in Sap knock-out mice. Th1/Th2 imbalance in humans, as well as in mice, may play an important role in the pathogenesis of XLP.

Adult↗
PubMed2005

[Cyclosporin].

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ATP Binding Cassette Transporter, Subfamily B, Mem↗