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Biomedical subjects

Y Kawabata

Publications and source records attributed to Y Kawabata.

At least 37 records · Page 2Linked to original sources
PubMed2001

A clinical analysis of 52 adult patients with hemophagocytic syndrome: the prognostic significance of the underlying diseases.

We retrospectively analyzed 52 adult patients with hemophagocytic syndrome (HPS). The underlying diseases were heterogeneous, including malignant lymphoma (lymphoma-associated hemophagocytic syndrome [LAHS]) in 26 patients, systemic lupus erythematosus in 3 patients, viral infections in 7 patients, and bacteria] or fungal infections in 6 patients. More than 83% of patients received prednisolone as an initial treatment. Multiple-agent chemotherapies (cyclophosphamide, doxorubicin, and vincristine) were administered to 96% of LAHS patients after a histopathological diagnosis of lymphoma. HPSs were controllable and remissions were achieved except for those patients with LAHS, fulminant Epstein-Barr virus-associated HPS, and an immunosuppressive state. Twenty-one (81%) of the LAHS patients had uncontrollable HPS and died of multiple organ failure and disseminated intravascular coagulation. The median survival time of LAHS patients was 83 days. In contrast, 3 (12%) of the other HPS patients died of multiple organ failure within 44 days.The clinical manifestations and the laboratory findings of LAHS and the other HPSs were too variable to establish the prognosis based only on the findings at the onset of HPS. The prognostic factors of adult HPS were found to be the underlying diseases, notably malignant lymphoma and infections, accompanied by the immunosuppressive state.

Adult↗
PubMed2001

Advanced gallbladder carcinoma with biliobiliary fistula, resected by hepatopancreatoduodenectomy, in an aged patient.

We report a 78-year-old man with a gallbladder carcinoma and biliobiliary fistula, diagnosed by percutaneous transhepatic cholangioscopic biopsy through the fistula. The impacted stones in the common hepatic duct were crushed, and then selective cholangiography under percutaneous transhepatic cholangioscopy (PTCS) revealed a biliobiliary fistula. Cholangioscopic biopsy tissues taken from the gallbladder revealed adenocarcinoma, but biopsies taken from the fistula revealed no evidence of malignancy. Further investigations indicated that the gallbladder carcinoma involved the duodenum and the distal common bile duct. A hepatopancreatoduodenectomy, including both an extended right hepatic lobectomy with resection of the caudate lobe and a pancreatoduodenectomy, was performed. Despite the patient's advanced age, he made an unremarkable postoperative recovery and was able to enjoy an active social life for 8 months after the surgery. We discuss biliobiliary fistula associated with gallbladder carcinomas and the use of hepatopancreatoduodenectomy for advanced biliary cancer in aged patients.

Aged↗
PubMed2001

Polymorphism in gene for islet autoantigen, IA-2, and type 1 diabetes in Japanese subjects.

Autoantibodies against IA-2 have been detected in up to 86% of newly diagnosed patients with type 1 diabetes and appear to identify a subgroup of prediabetic subjects who rapidly progress to type 1 diabetes. We examined the association of IA-2 gene polymorphism with type 1 diabetes in Japanese subjects. A total of 276 Japanese subjects were studied for disease association and, in addition, another 53 patients were studied for association with the autoantibody status to IA-2. A microsatellite marker D2S1753E, located in the intron of the IA-2 gene, was used as a genetic marker in this study. In Japanese, two alleles (161mu and 165mu) were more frequent, and the 163mu allele was less frequent than in Caucasians (p = 0.0001). There was no significant difference in frequencies of alleles between diabetic patients and control subjects. The frequency of IA-2 gene polymorphism was not significantly different between patients stratified by age-at-onset, or between patients with and without susceptible HLA, DRB1*0405, DRB1*0802 and DRB1*0901. There was no significant difference in allele frequency of the IA-2 gene polymorphism between patients with and without autoantibody to IA-2. In conclusion, IA-2 gene polymorphism is not associated with either susceptibility to, or heterogeneity in type 1 diabetes in Japanese subjects.

Alleles↗
PubMed2001

Extensive clonal expansion of T lymphocytes causes contracted diversity of complementarity-determining region 3 and skewed T cell receptor repertoires after allogeneic hematopoietic cell transplantation.

We previously described skewed repertoires of the T cell receptor-beta chain variable region (TCRBV) and the TCR-alpha chain variable region (TCRAV) soon after allogeneic hematopoietic cell transplantation. To determine the characteristics of skewed TCRBV after transplantation, we examined the clonality of T lymphocytes carrying skewed TCRBV subfamilies and determined the CDR3 sequences of expanded T cell clones. In all 11 recipients examined, TCR repertoires were skewed, with an increase of certain TCRBV subfamilies that differed among individuals. In nine of 11 patients, clonal/oligoclonal T cell expansion was observed, although the expanded T cells were not necessarily oligoclonal. The extent of expansion after transplantation appeared to predict clonality. The arginine (R)-X-X-glycine (G) sequence was identified in clonally expanded T cells from four of five recipients examined, and glutamic acid (E), aspartic acid (D) and alanine (A) were frequently inserted between R and G. These results suggest that T lymphocyte expansion may result from the response to antigens widely existing in humans, and that the extensive clonal expansion of a limited number of T cells leads to contracted CDR3 diversity and post-transplant skewed TCR repertoires.

Clone Cells↗
PubMed2001

Identification of the T cell clones expanding within both CD8(+)CD28(+) and CD8(+)CD28(-) T cell subsets in recipients of allogeneic hematopoietic cell grafts and its implication in post-transplant skewing of T cell receptor repertoire.

We have previously reported that skewed repertoires of T cell receptor-beta chain variable region (TCRBV) and TCR-alpha chain variable region (TCRAV) are observed at an early period after allogeneic hematopoietic cell transplantation. Furthermore, we found that T lymphocytes using TCRBV24S1 were increased in 28% of the recipients of allogeneic grafts and an increase of TCRBV24S1 usage was shown to result from clonal expansions. Interestingly, the arginine residue was frequently present at the 3' terminal of BV24S1 segment and was followed by an acidic amino acid residue within the CDR3 region. These results suggest that these clonally expanded T cells are not randomly selected, but are expanded by stimulation with specific antigens. This study was undertaken to elucidate the mechanisms of the post-transplant skewing of TCR repertoires. Since the CD8(+)CD28(-)CD57(+) T cell subset has been reported to expand in the peripheral blood of patients receiving allogeneic hematopoietic cell grafts, we examined the TCRAV and TCRBV repertoires of the CD8(+)CD28(-) T cell and CD8(+)CD28(+) T cell subsets, and also determined the clonality of both T cell populations. In all three recipients examined, the CD8(+)CD28(-) T cell subset appeared to define the post-transplant TCR repertoire of circulating blood T cells. Moreover, the CDR3 length of TCRBV imposed constraints in both CD8(+)CD28(-) T cell and CD8(+)CD28(+) T cell subsets. The DNA sequences of the CDR3 region were determined, and the same clones were identified within both CD8(+)CD28(-) and CD8(+)CD28(+) T cell subsets in the same individuals. These results suggest that the clonally expanded CD8(+)CD28(-) T cells after allogeneic hematopoietic cell transplantation derive from the CD8(+)CD28(+) T cell subset, possibly by an antigen-driven mechanism, resulting in the skewed TCR repertoire.

Amino Acid Sequence↗
PubMed2001

Oligoclonal expansion of CD4(+)CD28(-) T lymphocytes in recipients of allogeneic hematopoietic cell grafts and identification of the same T cell clones within both CD4(+)CD28(+) and CD4(+)CD28(-) T cell subsets.

Recipients of allogeneic bone marrow grafts have clonally expanded CD8(+)CD28(-) T lymphocytes during the early period after transplantation, which leads to skewing of T cell receptor (TCR) repertoires. Here, we have addressed the question of whether clonal expansion of CD28(-) T cells is also observed in CD4(+) T lymphocytes after human allogeneic hematopoietic cell transplantation. We found that the fraction of T cells lacking CD28 expression in the CD4(+) subset was increased after transplantation, and expanded CD4(+)CD28(-) T lymphocytes carrying certain TCRBV subfamilies showed limited TCR diversity. In order to further study the ontogeny of CD4(+)CD28(-) T cells, we analyzed the complementarity-determining region 3 (CDR3) of the TCR-beta chain of CD4(+)CD28(+) and CD4(+)CD28(-) cells. We identified the same T cell clones within both CD4(+)CD28(-) and CD4(+)CD28(+) T cell subsets. These results suggest that both subsets are phenotypic variants of the same T cell lineage.

Amino Acid Sequence↗
PubMed2001

Scintigraphic evaluation of chronic osteomyelitis of the mandible in SAPHO syndrome.

A patient with SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis and osteitis) was evaluated by combined scintigraphy. (99m)Tc HMDP scintigraphy showed accumulation in the sternum and lumbar vertebrae as well as the right mandible, whereas (67)Ga citrate showed an accumulation in the right mandible, but not in the sternum or lumbar vertebrae. These results are consistent with chronic osteomyelitis in the mandible.

Acquired Hyperostosis Syndrome↗
PubMed2001

Two kinds of Hutchinson's sign, benign and malignant.

We examined 6 subungual melanomas in situ and 18 melanocytic nevi and compared pigmentation of the nail plates and hyponychium with the use of a dermatoscope. Hutchinson's sign on the hyponychium was not always evidence of subungual melanoma because it can be seen in both diseases. However, there was a wide difference in their dermatoscopic features. We believe that observation of pigmentation on the hyponychium with the use of a dermatoscope contributes to the precise diagnosis of subungual melanoma.

Adolescent↗
PubMed2001

Radiographic evaluation of malignant fibrous histiocytoma affecting maxillary alveolar bone: a report of 2 cases.

OBJECTIVE: The purpose of this study was to evaluate the radiographic findings of malignant fibrous histiocytoma (MFH) and to discuss the contribution of these findings to a differentiation of MFH from other malignant tumors of the head and neck. STUDY DESIGN: Two cases of MFH of the maxillary sinus affecting the alveolar bone were evaluated radiographically and scintigraphically. RESULTS: We reported the following findings, which have only seldom been described: the presence of fairly well-demarcated bone destruction in the intraoral radiograph; the relatively smooth surface, uniform density, or no necrotic area of the tumor; in computed tomograph images showing the clear separation of the tumor from surrounding soft tissues; bone scintigraphs reflecting the periosteal reaction to tumor invasion; and lymphoscintigraphy of the metastatic lymph nodes. CONCLUSION: We evaluated the radiographic findings from 2 cases of MFH and describe findings that may aid in the differentiation of MFH. These radiographic features may help dentists differentiate MFH from other malignant tumors in the head and neck, although MFH is a rare disease and there are no radiographic findings that would indicate a specific diagnosis of MFH.

Alveolar Process↗
PubMed2001

Dynamic scintigraphy with thallium-201 chloride (Tl-201) for the diagnosis of tumors of the head and neck.

OBJECTIVE: The purpose of this study was to differentiate between malignant tumors and benign tumors of the head and neck by means of thallium-201 chloride scintigraphy. STUDY DESIGN: Thallium-201 chloride (Tl-201) scintigraphy and Ga-67 citrate (Ga-67) scintigraphy were performed in 10 patients with a benign tumor and in 90 patients with a malignant tumor. The blood flow index and the tumor retention index were obtained by means of Tl-201 scintigraphy. The blood flow index = the count of tumor/the count of control in the early dynamic scan from 30 to 120 seconds after injection, and the tumor retention index = (the count of tumor/the count of control in the delayed dynamic scan 2.5 hours after injection)/(the count of tumor/the count of control in the early dynamic scan from 4 to 5 minutes after injection). RESULTS: The early and delayed scans with Tl-201 demonstrated a very high correlation with the blood flow index. The tumor retention index had a tendency to increase in malignant tumors, especially in the poorly differentiated tumors and the severely invasive tumors. Likewise, the tumor retention index decreased in benign tumors. These results proved to be statistically significant, and in turn Tl-201 scintigraphy was deemed superior to Ga-67 scintigraphy. Tl-201 scintigraphy was also useful in detecting small-size tumors. CONCLUSION: The tumor retention index of Tl-201 was useful for the differentiation of malignant tumors of the head and neck from benign tumors of the same areas.

Adenocarcinoma↗
PubMed2001

Inhibition of drug metabolism in human liver microsomes by nizatidine, cimetidine and omeprazole.

1. The inhibitory effects of cimetidine, nizatidine and omeprazole on the metabolic activity of CYP2C9, 2C19, 2D6 and 3A were investigated in human liver microsomes. Both cimetidine and omeprazole inhibited each of the CYP subfamily enzymes; in particular, omeprazole extensively inhibited the hydroxylation of S-mephenytoin (CYP2C19, Ki = 7.1 microM). Nizatidine exhibited no inhibition of any of the CYP isoforms examined. 2. Cimetidine inhibited the hydroxylation of tolbutamide but not of diclofenac, whereas omeprazole inhibited the hydroxylation of diclofenac but not that of tolbutamide. The ability to inhibit CYP2C9 varied with incubation time, as measured by the metabolic rate constant for the substrates. Therefore, suitable substrates and incubation times must be selected in inhibition studies examining metabolic clearance and the mechanism of inhibition of these drugs. 3. Nizatidine did not inhibit the metabolism of cisapride, glibenclamide, benidipine and simvastatin. Omeprazole inhibited the metabolism of cisapride (Ki = 0.4 microM), glibenclamide (11.7 microM) and benidipine (6.5 microM), whereas cimetidine inhibited the metabolism of glibenclamide (11.6 microM). To avoid drug-drug interactions, care needs to be taken to select suitable medicines for co-administration with anti-ulcer drugs.

Anti-Ulcer Agents↗
PubMed2001

Generation of cytotoxic T lymphocytes by MHC class I ligands fused to heat shock cognate protein 70.

Immunization with gp96 and heat shock cognate protein 70 (hsc70) purified with in vivo bound naturally occurring peptides or bound to synthetic peptides by in vitro reconstitution has been shown to induce peptide-specific cytotoxic T lymphocytes (CTL). In addition, mycobacterial heat shock protein 70 covalently fused to ovalbumin (OVA)-derived fragments has been shown to generate MHC class I-restricted CTL responses. Here, we genetically fused five different CTL epitopes, including peptides derived from Plasmodium yoelii circumsporozoite protein, tumor antigens, HY antigen and OVA, to either the N- or C-terminus of murine hsc70 and expressed the resulting proteins in Escherichia coli. Vaccination with all five fusion proteins induced peptide-specific CTL, indicating that no cognate flanking regions of CTL epitopes are necessary for the immune response. The point of injection was crucial for CTL induction. CD4(+) T cells were not required for the priming of CD8(+) T cells and vaccination with bone marrow-derived dendritic cells pulsed with hsc70 fusion proteins also elicited CTL responses. Furthermore, by using deletion mutants of hsc70, we identified amino acid residues 280-385 of hsc70 as the region most critical for inducing the CTL response.

Animals↗
PubMed2001

Induction of necrosis factor-alpha and interleukin-6 in mice in vivo and in murine peritoneal macrophages and human whole blood cells in vitro by Micrococcus luteus teichuronic acids.

Earlier studies showed that Micrococcus luteus cells and cell walls induced anaphylactoid reactions leading to death, in some instances within 1 h, in C3H/HeN mice primed with muramyl dipeptide (MDP). They also induced serum cytokines in the surviving mice. The present study investigated the structural components responsible for these activities. Teichuronic acids, a component of M. luteus cell walls, induced tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in MDP-primed C3H/HeN mice. Peptidoglycans had little effect on the cytokine-inducing activities. Reducing teichuronic acids, i.e., teichuronic acids whose carboxyl groups had been reduced, lost their cytokine-inducing activities. Neither peptidoglycans nor teichuronic acids induced anaphylactoid reactions in the MDP-primed mice. Purified teichuronic acids also induced TNF-alpha and IL-6 production in C3H/HeN murine peritoneal macrophages and human whole-blood cells in the culture, but reduced teichuronic acids did not. The purified teichuronic acids induced no TNF-alpha and only low levels of IL-6 in MDP-primed C3H/HeJ mice, and neither cytokine in peritoneal macrophage cultures from C3H/HeJ mice with a single point of mutation in Toll-like receptor 4 (TLR4) gene. These findings suggest that induction of cytokines by teichuronic acids is mainly TLR4-dependent.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed2001

Chronic bronchiolitis with associated eosinophilic lung disease (eosinophilic bronchiolitis).

We encountered an adult patient with dyspnea, eosinophilia and bronchiolitis. He was diagnosed as having diffuse panbronchiolitis, and was treated with erythromycin for 3 years, but his symptoms had gradually worsened. Bronchoalveolar lavage showed marked eosinophilia, and video-assisted thoracoscopic lung biopsy revealed chronic bronchiolitis with associated eosinophilic lung disease (eosinophilic bronchiolitis). To our knowledge, no case of eosinophilic bronchiolitis has been reported in the literature.

Bronchiolitis↗
PubMed2001

Activation of soil and chemical reagents exposed to the neutrons released by the JCO criticality accident in Tokai-mura.

Specific activities (Bq/g-element) of residual neutron-induced radionuclides by the JCO criticality accident were measured for soil, concrete block and chemical reagent samples collected in the JCO campus. Induced radionuclides such as 24Na, 46Sc, 54Mn, 59Fe, 60Co, 65Zn, 82Br, 122Sb, 134Cs and 140La were detected in the samples, depending on the ground distance from the accident point and the sampling date. Apparent thermal, epi-thermal and fast neutron fluences, which reached the sample at each point, were roughly estimated from the specific activities and cross sections of the target nuclides taken from a literature. The present data are believed to be important as validation data for a three-dimensional neutron transport model calculation.

Construction Materials↗
PubMed2001

Sequence analysis of candidate genes for common susceptibility to type 1 and type 2 diabetes in mice.

Although type 1 and type 2 diabetes are regarded as clinically distinct diseases, several lines of evidence have suggested common genetic factors between the two types of diabetes. The non-obese diabetic (NOD) mouse, an animal model of type 1 diabetes, and the Nagoya-Shibata-Yasuda (NSY) mouse, a model of type 2 diabetes, are derived from the same outbred colony, Jcl:HCR, suggesting a shared susceptibility between the two types of diabetes in mice. Genetic as well as functional studies have supported the possibility that Tcf2, which encodes the transcription factor, hepatocyte nuclear factor 1beta (HNF-1beta), is a candidate gene for the common susceptibility between NSY and NOD mice. Txn, encoding thioredoxin which is a redox (reduction/oxidation)-active protein, is also a positional and functional candidate for a common susceptibility gene. To investigate whether either of these two genes is a common susceptibility gene, the coding nucleotide sequences of these two genes were compared among the NSY, NOD and control C3H strains. The coding sequence of Tcf2 of the NOD mouse was identical to that of the C3H mouse, but was different from that of the NSY mouse. The coding sequence of Txn was identical in the three strains. These data suggest that neither of the two genes is a common susceptiblity gene between type 1 and type 2 diabetes in mice.

Animals↗
PubMed2001

[A case of drug-induced interstitial pneumonitis in rheumatoid arthritis treated with bucillamine].

We report a case of bucillamine-induced interstitial pneumonitis in a 57-year-old woman. Rheumatoid arthritis was diagnosed in May 1999, and she was treated with bucillamine from June 1999, with a favorable outcome. After complaining of cough, fever, and dyspnea in October, she was admitted to this hospital. Blood gas analysis showed severe hypoxemia. The chest CT revealed both bilateral diffuse ground-glass opacity along the bronchovascular bundles, and thickening of the interlobular septa. We suspected bucillamine-induced interstitial pneumonitis from the findings of the CT scan, BALF and TBLB, and also from the improvement of PaO2 after the withdrawal of bucillamine. We treated the patient with prednisolone, and a favorable response was noted. A lymphocyte stimulation test using bucillamine was positive. A video-assisted thoracic surgery lung biopsy showed findings compatible with acute interstitial pneumonia without the association of hyaline membrane formation. A focal fibrosis was also observed. We believe that this is the only reported case of pathologically proven bucillamine-induced interstitial pneumonitis, in which a surgical lung biopsy was performed.

Anti-Inflammatory Agents, Non-Steroidal↗