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T Horiuchi

Publications and source records attributed to T Horiuchi.

At least 19 recordsLinked to original sources
PubMed2006

Prevention of steroid-induced osteonecrosis of femoral head in systemic lupus erythematosus by anti-coagulant.

Although osteonecrosis of femoral head (ONF) is one of the serious complications in systemic lupus erythematosus (SLE) associated with corticosteroid therapy, there has been few trials of prevention of ONF described. We aimed to prevent ONF in steroid-treated SLE patients using anticoagulant, warfarin, conducting a multicenter prospective study. Sixty newly diagnosed SLE patients requiring 40 mg/day or more prednisolone were alternately assigned to either of two groups; a warfarin group and a control one. Warfarin (1 to approximately 5 mg/day) was started together with the beginning of steroid therapy and continued at least for three months. Patients were observed for the development of silent ONF by magnetic resonance imaging (MRI) and symptomatic ONF by plain radiography for over five years. The warfarin group consisted of 31 patients (62 hips) and the control one 29 patients (58 hips). Silent ONF developed in 13 hips (21%) and 19 hips (33%) in the warfarin group and the control group, respectively (P = 0.13). On the other hand, warfarin tended to prevent symptomatic ONF; only three hips of 62 (4.8 %) in the warfarin group and eight hips of 58 (14%) in the control group (P = 0.08) developed silent ONF. It was also found that silent ONF developed, if it did, very early; within three months in 16 of 18 patients (89%). Among risk factors for silent ONF, steroid pulse therapy was most outstanding and it seemed to overcome the effect of warfarin. Taken together, for the time being, anti-coagulant therapy, if not significantly sufficient, may be of use for the prevention of steroid-induced ONF in SLE. We consider that this study added to important evidence for the pathogenesis and prevention of ONF.

Adolescent↗
PubMed2005

A phase I-II trial of autologous peripheral blood stem cell transplantation in the treatment of refractory autoimmune disease.

OBJECTIVES: To carry out a phase I-II trial to elucidate the feasibility and efficacy of high dose cyclophosphamide (CY) supported by autologous peripheral blood stem cell transplantation (PBSCT) in the treatment of severe and refractory autoimmune disease (AD). METHODS: Peripheral blood stem cells (PBSCs) were mobilised during haematological recovery after relatively high dose CY (2 g/m2) for 2 days, followed by administration of granulocyte colony stimulating factor. After collecting PBSCs--more than 2x10(6) CD34+ cells/kg--by apheresis, CD34+ cells were immunologically selected and cryopreserved. Eight patients were enrolled--five had systemic sclerosis (SSc) alone, one had SSc with systemic lupus erythematosus, one amyopathic dermatomyositis (ADM), and one Wegener's granulomatosis (WG). All of the patients were treated with high dose CY (50 mg/kg) for 4 days and autologous PBSCT. RESULTS: Haematopoietic reconstitution was rapid and sustained. Toxicity due to the regimen included various infections such as pneumonia, sepsis, cystitis, herpes zoster, and acute heart failure. However, there was no treatment related mortality. Encouraging results were obtained after autologous PBSCT. Sclerosis of the skin was markedly improved in all of the patients with SSc. Interstitial pneumonia (IP), evaluated by PaO2, serum KL-6 levels, and pulmonary high resolution computed tomography, improved significantly. In a patient with ADM, severe and progressive IP also improved markedly. In a patient with WG, the size of the left orbital granuloma decreased substantially, resulting in reduction of the exophthalmos. CONCLUSIONS: These observations suggest that high dose CY with autologous PBSCT is feasible and may be effective in the treatment of severe and refractory AD.

Adult↗
PubMed2005

Evaluation of activation treatments for blastocyst production and birth of viable calves following bovine intracytoplasmic sperm injection.

The objective of this study was to compare the effectiveness of different methods of bovine oocyte activation following intracytoplasmic sperm injection (ICSI) in terms of oocyte cleavage and blastocyst rates, and calf production. Oocytes were harvested, post mortem, from the ovaries of Japanese Black heifers or cows. ICSI was carried out using a piezo-electric actuator. The injected or sham-injected oocytes that were assigned to three activation treatments, each replicated three times, were studied: (1) exposure to 5 microM ionomycin for 5 min (ionomycin); (2) exposure to 5 microM ionomycin for 5 min followed by culture in TCM199 for 3 h and a further 3h culture in 1.9 mM 6-dimethylaminopurine (DMAP-ionomycin+DMAP); (3) exposure to 7% ethanol in TCM199 for 5 min, 4 h after ICSI (ethanol). One or two blastocysts from the ionomycin+DMAP (8 recipients) and ethanol (17 recipients) oocyte activation treatments were non-surgically transferred into Holsteins for the study of calf production. The highest cleavage and blastocyst production rates were observed in the ionomycin+DMAP treatment (83.9% and 40.1%) by the ICSI. These rates were significantly (P<0.05) higher than those for the ionomycin oocyte activation treatment (57.6% and 18.2%) but did not differ from the ethanol treatment (75.6% and 29.4%). In the sham-injected, the highest blastocyst production rates were observed for the ionomycin+DMAP and ethanol treatments (10.7% and 11.3%). Pregnancy and birth rates for blastocysts derived from the ethanol oocyte activation treatment (58.8% and 47.4%) were significantly higher (P<0.05) than those of the ionomycin+DMAP treatment (12.5% and 9.2%). The results showed that post-ICSI oocyte activation with ethanol is more effective than activation with ionomycin alone or with ionomycin+DMAP for the production of viable blastocysts and calves.

Adenine↗
PubMed2005

Association of MBL gene polymorphisms with major bacterial infection in patients treated with high-dose chemotherapy and autologous PBSCT.

A growing body of evidence indicates that genetic factors are involved in an increased risk of infection. We investigated whether mannose-binding lectin (MBL) gene polymorphisms that cause low levels of MBL are associated with the occurrence of major infections in patients, mainly bearing hematological malignancies, after high-dose chemotherapy (HDT) rescued by autologous peripheral blood stem cell transplantation (auto-PBSCT). A retrospective evaluation of 113 patients treated with HDT and auto-PBSCT revealed that the low-producing genotypes, B/B and B/LXA, were associated with major bacterial infection (P=0.0016, OR 7.9). We next performed a nation-wide large-scale study to assess the allele frequency of the MBL coding mutation in a total of 2623 healthy individuals in Japan. The frequency of allele B was estimated to be approximately 0.2, almost the same in seven different areas of Japan. This common occurrence suggests that MBL deficiency may play an important role in the clinical settings of immunosuppression.

Alleles↗
PubMed2005

Very early development of steroid-associated osteonecrosis of femoral head in systemic lupus erythematosus: prospective study by MRI.

The objective of this study was to define prospectively the early development of corticosteroid-induced osteonecrosis of femoral head (ONF) in patients with systemic lupus erythematosus (SLE) and to identify the association of initial steroid treatment with the development of early (silent) ONE Forty-five patients who were newly diagnosed as having SLE and required 40 mg/day or more prednisolone were enrolled. To detect silent ONF, examinations using magnetic resonance imaging (MRI) were done three months after starting steroid therapy, followed by every year's MRI and plain radiography for over five years. Clinical and laboratory data were compared between silent ONF and non-ONF groups. Of 45 patients, 15 (33%) developed silent ONF and five (11%) symptomatic ONE It was of interest that MRI detected silent ONF very early (by three months) in 14 patients (93%). It should be noted that pulse therapy with 1000 mg/day methylprednisolone was found to be done very frequently (13 of 15, 87%) in the silent ONF group compared to non-ONF group (11 of 30, 37%) (P < 0.01) although other clinical features were not significantly different between both groups. High dose corticosteroids caused elevation of serum levels of total cholesterol, albumin, and leukocyte count in most of patients. The degree of elevation of those parameters at one or three months was more prominent in the silent ONF group. In particular, the change ratio of total cholesterol at one month was outstanding in the silent ONF group compared to non-ONF group (0.551 versus 0.374, P < 0.05). In conclusion, pathological ONF develops very early in one-third of SLE patients who received high dose corticosteroids and steroid pulse therapy could be a significant risk factor. An abrupt elevation of serum total cholesterol and/or sensitivity to steroids seem to be associated with the pathogenesis of ONF.

Adolescent↗
PubMed2004

Raised serum APRIL levels in patients with systemic lupus erythematosus.

OBJECTIVE: To determine whether serum levels of a proliferation-inducing ligand (APRIL) are raised in patients with systemic lupus erythematosus (SLE) and correlate with autoantibody titres or disease activity, or both. METHODS: Serum samples from 48 patients with SLE, 41 normal healthy subjects, and 21 patients with rheumatoid arthritis (RA) were assayed for APRIL by enzyme linked immunosorbent assay. Medical charts were retrospectively reviewed for autoantibody titres and immunoglobulin levels. Disease activity was assessed using the British Isles Lupus Assessment Group (BILAG) index. RESULTS: The APRIL levels in the serum samples from patients with SLE were significantly higher than in those from healthy controls and those from patients with RA. Serum APRIL levels did not correlate with serum IgG and IgM levels, but had a tendency to correlate with anti-double stranded DNA antibody titres. Moreover, serum APRIL levels correlated significantly with musculoskeletal manifestations among patients with SLE when assessed by the BILAG index. CONCLUSION: APRIL may be an important factor in raised autoantibody titres and musculoskeletal disease in patients with SLE. Patients with raised serum APRIL levels may be ideal candidates for therapeutic targeting of APRIL.

Adult↗
PubMed2004

Review of combination of peritoneal dialysis and hemodialysis as a modality of treatment for end-stage renal disease.

Because the contribution of residual renal function (RRF) to total solute clearance is often significant in continuous ambulatory peritoneal dialysis (CAPD), loss of RRF over time can lead to inadequate dialysis if appropriate prescription management strategies are not pursued. Additionally, declines in ultrafiltration caused by increases in peritoneal permeability may limit continuation of CAPD therapy. Peritoneal dialysis and hemodialysis (PD + HD) combination therapy (complementary dialysis therapy) is an alternative method. This therapy allows the patient to maintain daily activities, as with CAPD, while undergoing once-a-week HD supplements for the insufficient removal of solutes and water. This therapy allows for the continuation of PD without shifting to total HD in PD patients who continue to have uremic symptoms even after individualization of the PD prescription. This treatment option is psychologically more acceptable to patients and may be expected to provide such accompanying beneficial effects as peritoneal resting, improvement of QOL and reduction in medical cost.

Combined Modality Therapy↗
PubMed2003

A novel polymorphism of the human APRIL gene is associated with systemic lupus erythematosus.

OBJECTIVE: We investigated the association of gene polymorphisms in APRIL, a new member of the TNF family, with systemic lupus erythematosus. METHODS: To detect polymorphisms of the human APRIL gene by exon-specific polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) analysis, we first determined the structure of the human APRIL gene. We designed exon-specific oligonucleotide primers according to the genomic DNA sequence of APRIL. All of the coding regions in exons of the APRIL gene were analysed by exon-specific PCR-SSCP in 148 SLE patients and 146 unaffected controls, then the nucleotide sequences of exons that displayed aberrant bands were determined. RESULTS: The human APRIL gene comprised at least six exons with five introns, spanning approximately 2.8 kilobases of the genomic DNA. By exon-specific PCR-SSCP, we identified two novel polymorphisms at codons 67 and 96. Both had amino acid substitutions: G67R and N96S respectively. Only the 67G allele was associated with SLE in 148 Japanese SLE patients, with allele frequency 0.662 compared with 0.575 for 146 unaffected controls (P=0.0302). The frequency of the individuals who possessed at least one 67G allele in SLE patients (91.9%) was significantly higher than that in the unaffected controls (80.1%) (P=0.0036). CONCLUSION: The 67G allele of APRIL may be a contributing factor in the pathogenesis of SLE.

Adolescent↗
PubMed2003

Sarcoplasmic reticulum Ca2+ release is not a dominating factor in sinoatrial node pacemaker activity.

Recent work on isolated sinoatrial node cells from rabbit has suggested that sarcoplasmic reticulum Ca2+ release plays a dominant role in the pacemaker potential, and ryanodine at a high concentration (30 micromol/L blocks sarcoplasmic reticulum Ca2+ release) abolishes pacemaking and at a lower concentration abolishes the chronotropic effect of beta-adrenergic stimulation. The aim of the present study was to test this hypothesis in the intact sinoatrial node of the rabbit. Spontaneous activity and the pattern of activation were recorded using a grid of 120 pairs of extracellular electrodes. Ryanodine 30 micromol/L did not abolish spontaneous activity or shift the position of the leading pacemaker site, although it slowed the spontaneous rate by 18.9+/-2.5% (n=6). After ryanodine treatment, beta-adrenergic stimulation still resulted in a substantial chronotropic effect (0.3 micromol/L isoproterenol increased spontaneous rate by 52.6+/-10.5%, n=5). In isolated sinoatrial node cells from rabbit, 30 micromol/L ryanodine slowed spontaneous rate by 21.5+/-2.6% (n=13). It is concluded that sarcoplasmic reticulum Ca2+ release does not play a dominating role in pacemaking in the sinoatrial node. The full text of this article is available at http://www.circresaha.org.

Action Potentials↗
PubMed2003

Aberrant HS1 molecule in a patient with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the activation of autoreactive B lymphocytes, which are supposed to carry aberrant signal transduction after the stimulation of B-cell receptor (BCR). To investigate abnormalities in BCR-mediated signaling pathway in lupus B lymphocytes, we analyzed HS1, a molecule downstream of BCR, in 80 Japanese SLE patients. We identified 37 amino acid deletion of HS1 in a 25-year-old female patient, and the aberrant HS1 lacked a part of a functional motif. Analysis of genomic DNA revealed that the aberrant HS1 was caused by exon skipping. Family study showed that the patient as well as her father and sister are heterozygous for the abnormality. WEHI-231 cell, a mouse B cell line, transfected with the aberrant HS1 displayed a significantly increased cell death upon cross-linking of BCR. Additionally, peripheral B lymphocytes from the patient exerted increased apoptosis after BCR stimulation compared to those from control SLE patients. These data suggest that the aberrant HS1 molecule may transmit an accelerated signal after BCR stimulation and may play a role in the activation of autoreactive B lymphocytes.

Adaptor Proteins, Signal Transducing↗
PubMed2003

Idiopathic gastric rupture in a 3-month-old girl.

UNLABELLED: This case reports on idiopathic gastric rupture in a 3-mo-old girl who had frequent episodes of vomiting and abdominal distension the day before admission to the clinic. Metabolic acidosis was detected and rotavirus antigen was identified in the stools. Abdominal X-rays and CT scans revealed free air and fluid in the abdominal cavity, leading to a diagnosis of gastrointestinal perforation. During surgery, idiopathic gastric rupture was detected and treated. The postoperative course was uneventful. CONCLUSION: Idiopathic gastric rupture is extremely rare in childhood beyond the neonatal period. Early diagnosis and surgery are mandatory if children with this condition are to be saved.

Female↗
PubMed2002

Study on social responses (encouraging public awareness) to sudden infant death syndrome: evaluation of SIDS prevention campaigns.

The sudden infant death syndrome (SIDS) prevention campaign promulgated by the SIDS Family Associations was initiated and directed to medical professionals in 1996 and to mothers in 1997. In mid-1998, the Ministry of Health and Welfare began to support this campaign. In parallel with these moves and with cooperation from the study group of the Ministry of Health and Welfare and the SIDS Family Associations of Japan, a Japanese segment of the International Child Care Practices Survey (ICCPS) was conducted in two phases--from 1996 to 1997 and from 1998 to 1999--to observe the trends in risk factors for SIDS that may exist in the child rearing environment in Japan. Consequently, after the SIDS prevention campaign, the risk factors for SIDS, such as the practice of placing infants in a prone posture, smoking, and formula feeding, were reduced. Correspondingly, it was shown that the incidence of SIDS in Japan and in Kanagawa Prefecture where the survey was carried out considerably decreased (0.42-0.24 per 1000 live births). These data indicate that this prevention campaign has been effective.

Health Education↗
PubMed2002

Distinct TCRAV and TCRBV repertoire and CDR3 sequence of T lymphocytes clonally expanded in blood and GVHD lesions after human allogeneic bone marrow transplantation.

Acute graft-versus-host disease (GVHD) is a disorder involving the skin, gut and liver that is caused by mismatches of major and/or minor histocompatibility antigens between the HLA-identical donor and recipient. If T lymphocytes infiltrating GVHD lesions recognize antigens expressed in these organs, T cell clones should expand in inflammatory tissues. We previously reported that recipients of allogeneic bone marrow grafts have clonally expanded TCRalphabeta(+) T lymphocytes soon after transplantation, which leads to a skew of TCR repertoires. To establish whether or not the same antigens cause clonal expansion of T lymphocytes in both blood and GVHD tissues, we examined the usage of TCR alpha and beta chain variable regions (TCRAV and TCRBV) and determined the complementarity-determining region 3 (CDR3) of T lymphocytes clonally expanded in circulating blood and GVHD lesions. We found that the repertoires and CDR3 diversity of TCRAV and TCRBV differed between the GVHD lesions and circulating blood, suggesting the selective recruitment of antigen-specific T cells into GVHD tissues. We also found that the usage of TCRAV and TCRBV by the clonally expanded T lymphocytes and their CDR3 sequences differed between the GVHD tissues and blood. These results suggest that the antigen specificity of TCRalphabeta(+) T lymphocytes clonally expanded in blood and GVHD lesions is different.

Acute Disease↗
PubMed2002

Analysis of the human sperm centrosomal function and the oocyte activation ability in a case of globozoospermia, by ICSI into bovine oocytes.

BACKGROUND: Centrosomal function and oocyte activation ability of human sperm from a case of globozoospermia was assayed by heterologous ICSI into bovine oocytes. METHODS: Microtubules and chromatin configuration in bovine oocytes were examined by immunofluorescence after heterologous ICSI with human sperm from two fertile donors and from a globozoospermic man. RESULTS: The microtubule array from the sperm centrosome, the 'sperm aster' and the male pronucleus were observed in bovine oocytes, following ICSI with round-headed sperm from a globozoospermic man. The rate of sperm aster formation and the rate of male pronuclear formation in the bovine oocytes injected with fertile donor sperm were 57.9 and 92.5% respectively; the respective values for oocytes injected with round-headed sperm without artificial oocyte activation were 15.8 and 31.0%. Ethanol activation after ICSI improved male pronuclear formation (84.9%) but not sperm aster formation rate (32.3%) of the globozoospermic patient. CONCLUSIONS: These data indicated that sperm from this patient with globozoospermia have centrosomal dysfunction and low ability for oocyte activation compared with fertile donor sperm. The centrosomal dysfunction may be one of the reasons for infertility in this patient.

Animals↗
PubMed2001

On-chip integration of sequential ion-sensing system based on intermittent reagent pumping and formation of two-layer flow.

A sequential ion-sensing system using a single microchip was successfully realized. The system developed here involves intermittent pumping of plural organic phases into a microchannel, followed by contact with a single aqueous phase to form a stable organic-aqueous two-layer flow inside the microchannel. Because the plural organic phases created by intermittent flow contain the same lipophilic pH indicator dye but different ion-selective neutral ionophores, different ions can be sequentially and selectively extracted into the different organic phases, where they can be determined by thermal lens microscopy (TLM). We used KD-A3 as the lipophilic pH indicator dye and valinomycin and DD16C5 as neutral ionophores to demonstrate sequential ion sensing of potassium and sodium ions by measuring the deprotonated dye caused by the ion extraction. The integrated microfluidic system proposed here allows multi-ion sensing, which is not easily demonstrated by conventional ion sensor technology using a solvent polymeric membrane. The minimum volume of single organic phase needed to obtain an equilibrium response without dilution by cross dispersion of two organic phases was ca. 500 nL in our system, indicating that the required amounts of expensive reagents in one measurement could be reduced to 1.7 ng and 2.8 ng for the dye and ionophore molecules, respectively.

Biosensing Techniques↗
PubMed2001

Microfluidic device for airborne BTEX detection.

We fabricated a microfluidic device for the optical detection of airborne benzene, toluene, ethylbenzene and xylenes (BTEX). The device consists of concentration and detection cells formed of 3 cm x 1 cm Pyrex plates. The concentration cell is composed of an adsorbent to concentrate the BTEX gases and a thin-film heater todesorb the concentrated gases from the adsorbent thermally. The collected gases are introduced into the detection cell, which is connected to optical fibers, to measure their absorption spectra. We optimized the device's operating conditions by studying the thermal characteristics of the concentration cell and the time profile of the gas concentration flowing in the detection cell. We used the device under optimized operating conditions to detect toluene gas as a typical example BTEX. The gas concentration amplification rate was approximately 2 orders of magnitude, and we successfully measured parts-per-million levels of toluene gas with this device.

Air Pollutants↗
PubMed2001

Enhanced homologous recombination caused by the non-transcribed spacer of the rDNA in Arabidopsis.

The problem of the low frequency of homologous recombination observed in higher plants has been approached in several ways. Here, we report a new strategy to enhance homologous recombination in Arabidopsis. In Escherichia coli and Saccharomyces cerevisiae, hotspots that enhance homologous recombination nearby have been identified in regions close to sites associated with the blocking of DNA replication forks or with intensive transcriptional activity. In yeast, a recombination hotspot (HOT1) was found in a region spanning two non-transcribed spacers (NTS) between ribosomal RNA genes (rDNA), which contains both a replication fork barrier ( RFB) and the promoter for transcription of the 35S rRNA gene. Since rDNA has a common structure among eukaryotes, we analyzed the effect of the endogenous NTS on homologous mitotic recombination in a higher plant. We constructed transgenic lines of Arabidopsis containing this NTS and a recombination substrate, in which two 3'- and 5'-deleted uidA (beta-glucuronidase) genes with partially overlapping sequences are separated by a Hyg(r) gene. Reconstitution of functional uidA genes by homologous recombination was monitored by histochemical GUS staining. We found that recombination occurred more frequently in all organs tested in F (Fork block) lines transgenic for the NTS than in C (Control) lines without the NTS. The average number of GUS+ spots on leaves in F lines was more than nine-fold higher than in C lines. Furthermore, by genomic Southern analysis, post-recombinational molecules were detected in a transgenic line, F43, which had an extremely high number of GUS+ blue spots. These results strongly suggest that NTS-dependent enhancement of homologous recombination may be a common feature of higher plants as well as yeast.

Arabidopsis↗