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Biomedical subjects

T Harada

Publications and source records attributed to T Harada.

At least 469 records · Page 26Linked to original sources

Optic neuropathy and acute transverse myelopathy in primary Sjögren's syndrome.

A case of Sjögren's syndrome with optic neuropathy and acute transverse myelopathy mimicking multiple sclerosis is described. The patient suddenly lost her visual acuity resulting in a permanent visual deficit in spite of the massive steroid therapy given. During the treatment the patient showed dry eye symptoms and was finally diagnosed as having primary Sjögren's syndrome. It is suggested that primary Sjögren's syndrome should be considered in the differential diagnosis of neurologic disorders that resemble multiple sclerosis.

Acute Disease↗

Expression and function of fibronectin receptors on peripheral mononuclear cells in IgA nephropathy.

The beta 1 integrin family, major adhesive receptors for the extracellular matrix (ECM), have been reported to be present in normal and diseased kidneys. Attachment of glomerular cells to ECM is mediated by beta 1 integrins. Several members of the beta 1 integrins are referred to as VLA (very late activation) antigens. Peripheral mononuclear cells also express VLA antigens in both resting and activated states. We examined the expression and function of VLA antigens on peripheral lymphocytes and monocytes in patients with IgA nephropathy using monoclonal antibodies (mAbs) specific for VLA alpha-chains. Peripheral lymphocytes from patients with IgA nephropathy expressed VLA-4 alpha and 5 alpha, but not VLA-1 alpha, 2 alpha or 3 alpha. Peripheral monocytes from patients with IgA nephropathy expressed VLA-2 alpha, 4 alpha and 5 alpha, but not VLA-1 alpha or 3 alpha. The expression of VLA adhesive receptors was observed in healthy individuals. Adhesion assay to fibronectin revealed augmented adhesion of mononuclear cells in IgA nephropathy (P < 0.05), and this increased adhesion was inhibited by mAbs to VLA-4 alpha and 5 alpha. The expression of beta 1 integrins in IgA nephropathy was similar to that of healthy individuals, but the function of these molecules in terms of adhesion to fibronectin though VLA-4 and VLA-5 is increased in these patients. These findings suggest that the activation of fibronectin receptors on peripheral mononuclear cells plays an important role in the pathogenic process of IgA nephropathy.

Adolescent↗

Visual function in patients with optic neuritis associated with acute transverse myelopathy in multiple sclerosis.

The authors reviewed the records of 20 patients with optic neuritis, all of whom were diagnosed as having clinically definite multiple sclerosis (MS). They were classified into two subgroups: Group A, consisting of 9 patients who had shown acute transverse myelopathy (ATM); and Group B, 11 patients without ATM. Four patients (44%) in Group A had complete visual loss, but none in Group B. Six patients (67%) in Group A had less than 0.1 visual acuity in the affected eye, but only 2 patients (18%) in Group B. Four patients in Group A showed evidence of anticardiolipin antibodies. While both groups were diagnosed as having clinically definite MS, there were differences between them in the clinical features. We assume that the patients with ATM may constitute a different subgroup among MS patients.

Acute Disease↗

Regulation of neutral cholesterol esterase activity by phospholipids containing negative charges in substrate liposome.

The effect of phospholipids on cholesteryl ester hydrolysis by neutral cholesterol esterase in alveolar macrophages was studied. Among the phospholipids used as emulsifiers, those with a negative charge, such as phosphatidylserine, phosphatidic acid, phosphatidylinositol, and cardiolipin, gave a higher level of hydrolysis by neutral cholesterol esterase than other less negatively charged phospholipids, such as phosphatidylcholine, lysophosphatidylcholine, phosphatidylethanolamine, and sphingomyelin. Phospholipase D treatment of liposomes emulsified with phosphatidylcholine produced phosphatidic acid and enhanced cholesteryl ester hydrolysis. Phospholipase A2 treatment produced lysophosphatidylcholine and decreased the hydrolysis. The hydrolysis of cholesteryl ester in lipid droplets obtained from cholesterol-laden macrophages elicited by thioglycollate in the rat peritoneal cavity was low compared to artificial liposomes emulsified with phosphatidylcholine. The reason for this was speculated to be that lipid droplets were low in total phospholipids and poor in phospholipids with strong negative charges but rich in phosphatidylethanolamine and sphingomyelin. These results suggest that the polar heads of phospholipids may play an important role in cholesteryl ester hydrolysis by neutral cholesterolesterase.

Animals↗

[A case of rhabdomyolysis with administration of intravenous vasopressin].

A 73-year-old man with alcoholic liver cirrhosis was admitted to our hospital because of massive hematemesis. He was treated with continuous intravenous infusion of vasopressin of 0.2 U/min. 22 hours after the infusion, he complained of myalgia, muscle weakness and skin mottling in the extremities. The skin lesion extended to the back. The serum CK and myoglobin levels were elevated to 52,280 IU/L and 84,400 ng/ml respectively. The urinary myoglobin level was elevated to 732,000 ng/ml. On the fifth hospital, he died of bleeding from the esophageal varices. Autopsy examination demonstrated necrosis of the skeletal muscle cells and myoglobin casts in the renal tubules. Our patient was probably hypersensitive to vasopressin because of underlying liver dysfunction. The massive myonecrosis might be induced from the following conditions; overreactive vasopressin-induced vasoconstriction resulted in ischemic muscle damage, and hypersensitive sarcoplasmic reticulum released excessive Ca2+ followed by muscle hypercontraction as seen in malignant syndrome or malignant hyperthermia.

Aged↗

Murine fibroblast growth factor receptor 1 gene generates multiple messenger RNAs containing two open reading frames via alternative splicing.

The arrangement of exons and introns encoding 5'-side of murine fibroblast growth factor (FGF) receptor 1 (FGFR-1) gene was mapped. A large intron with a size of 14 kb was identified between exon 1 and exon 2. In addition, all FGFR-1 subtypes including a unique variant form with 12 amino acids insertion and two amino acids deletion were observed to be able to be generated through alternative splicing. Furthermore, complete sequencing of the 5'-region of FGFR-1 mRNA revealed that a relatively large open reading frame precedes the major open reading frame encoding FGFR-1. These results indicate that FGFR-1 mRNAs are uniquely translated from an internal translation start site.

3T3 Cells↗

Usage of a novel class of germ-line Ig variable region gene for cationic anti-DNA autoantibodies in human lupus nephritis and its role for the development of the disease.

It has been shown that cationic anti-DNA autoantibodies have nephritogenic potential in murine models of lupus nephritis. We have recently reported the close relationship between the presence of cationic anti-DNA Abs and the development of lupus nephritis in humans. To investigate underlining mechanisms responsible for the production of pathogenic autoantibodies, we have isolated a cDNA clone (SC17) encoding cationic anti-DNA Ab of human systemic lupus erythematosus with severe nephritis that was present at the onset of disease but disappeared after disease remission with corticosteroids. We have also cloned a counterpart Ig VL germ-line gene (SG3) from purified neutrophils of the patient and found the presence of replacement mutations only in the CDR of SC17. Surprisingly, predicted isoelectric point (pI) of deduced protein encoded by SG3 was the most cationic one among those encoded by previously reported human V kappa germ-line genes in the DNA database. These results raise the possibility that the use of specific germ-line genes may confer a cationic charge on the anti-DNA Ab, whereas somatic mutations induce affinity maturation of anti-DNA Ab in human lupus nephritis. Anti-DNA Ab-secreting B cells, but not DNA nonbinding B cells of the same patient, constitutively expressed SC17 mRNA. This mRNA is also expressed by B cells from a vast majority of patients at the onset of disease or exacerbation of lupus nephritis. However, the mRNA is absent in B cells from patients with lupus nephritis during disease remission, systemic lupus erythematosus patients without renal involvements, and normal individuals. It is suggested that the SC17 mRNA expression of B cells is rather restricted to systemic lupus erythematosus patients with active renal involvements.

Adolescent↗

Simultaneous high-performance liquid chromatographic determination of 6 beta-hydroxycortisol and cortisol in urine with fluorescence detection and its application for estimating hepatic drug-metabolizing enzyme induction.

A simple and sensitive high-performance liquid chromatographic method is described for the simultaneous determination of 6 beta-hydroxycortisol (6 beta-OHF) and cortisol (F) in urine. Urine (1 ml) containing fludrocortisone as the internal standard is extracted with ethyl acetate. The extract is washed successively with sodium hydroxide solution and water, and subsequently dried under a stream of nitrogen. The residue is redissolved in methanol. The 6 beta-OHF, F and fludrocortisone in the methanol solution are oxidized by cupric acetate and the resulting glyoxal compounds are converted into fluorescent derivatives with 1,2-diamino-4,5-methylenedioxybenzene (DMB). The DMB derivatives of the corticosteroids are separated within 70 min on a reversed-phase column, L-Column ODS, using stepwise elution with methanol-acetonitrile-0.5 M ammonium acetate and detected fluorimetrically at 350 nm (excitation) and 390 nm (emission). The lower limits of detection for 6 beta-OHF and F are 1.8 pmol (680 pg) and 2.4 pmol (950 pg)/ml urine (0.6 pmol and 0.8 pmol/100 microliters injection volume), respectively, at a signal-to-noise ratio of 3. This method can be applied to the determination of urinary 6 beta-OHF, and the ratio of 6 beta-OHF to F in humans and in rhesus monkeys treated orally with phenobarbital as a hepatic drug-metabolizing enzyme inducer.

Administration, Oral↗

Mapping of a transcription element critical for expression of the fibroblast growth factor receptor 1 gene.

The fibroblast growth factor receptor 1 (FGFR1) gene has no TATA or CCAAT-elements. To examine its mechanism of expression, we characterized the transcription element of this gene. The basal promoter element was mapped to the 5'-flanking region from -89 to -43. The DNase I protection assay and gel shift analysis revealed that a nuclear protein extracted from FGFR1-expressing cells (NIH3T3 and SC-3), but not from FGFR1-nonexpressing cells (P3U1), could bind to the nucleotide sequence from -62 to -42. The molecular weight of this protein was approximately 100 kDa by Southwestern analysis. In addition, both the promoter activity and the nuclear protein binding activity were markedly impaired by the substitution of two bases within this footprint site. Interestingly, this footprint site appeared to lack the consensus sequence of the currently reported transcription factors. These results indicate that the 5'-flanking region from -62 to -42 plays a pivotal role in FGFR1 gene expression.

3T3 Cells↗

Acute low-tone sensorineural hearing loss without vertigo.

OBJECTIVE: To study the pathophysiological features of acute low-tone sensorineural hearing loss without vertigo (ALHL) and its correlation with Meniere's disease. DESIGN: Retrospective review of medical charts of patients with ALHL. SETTING: University hospital clinic. PARTICIPANTS: Eighty consecutive patients with ALHL, including 45 patients whose conditions were followed up for more than 3 years (average, 5 years 2 months; range, 3 years 3 months to 8 years). OUTCOME MEASURES: Age and sex distributions and results of audiological and neuro-otological tests, initial outcome, recurrence rates, and differences between patients with and without recurrence. RESULTS: About 75% (62/80) of the patients were between the ages of 30 and 60 years and the female-male ratio was 2:6. Positive glycerol test results were found in 74% (26/35) of patients and abnormally increased negative summating potential/action potential ratio in 63% (50/80). No abnormalities were found on neuro-otological tests. Hearing loss improved within 3 months in 84% (67/80) of the patients. Of 45 patients followed up for more than 3 years, 28 (62%) showed no evidence of recurrence, 12 (27%) developed cochlear Meniere's disease, and five (11%) developed classic Meniere's disease. No significant differences were found at the first examination between patients with and without recurrence. CONCLUSIONS: These results suggest that ALHL may be caused by endolymphatic hydrops confined to the cochlea and that ALHL does not always lead to cochlear or classic Meniere's disease.

Acute Disease↗

Fine antigen specificity of human gamma delta T cell lines (V gamma 9+) established by repetitive stimulation with a serotype (KTH-1) of a gram-positive bacterium, Streptococcus sanguis.

We have established human gamma delta T cell lines specific for Streptococcus sanguis (S. sanguis) KTH-1 present in normal oral cavity flora. The CD4-CD8-CD3+V gamma 9+V delta 1-CD45RO+ CD25+ T cell lines showed a proliferative response to the streptococcal antigen (Ag) in the presence of autologous antigen-presenting cells without apparent evidence of HLA restriction. The proliferative response of the gamma delta T cell lines was completely blocked by anti-TcR gamma delta monoclonal antibody (mAb) and anti-HLA class I mAb (W6/32), whereas anti-HLA classical class Ia mAb (B-H9; anti-HLA-A,B,C), anti-HLA class II mAb (anti-DR, anti-DQ, and anti-DP) and anti-CD4 mAb did not have any inhibitory effects. Surprisingly, the gamma delta T cell lines showed the proliferative response against the original bacterial Ag KTH-1 exclusively, and exhibited no cross-reactivity with nominal Ag such as purified protein derivative of tuberculin, tetanus toxoid and Mycobacterium tuberculosis, or the same species but different strain of S. sanguis, American Type Culture Collection (ATCC) standard strain (10556), or even with the same strain but different serotype of S. sanguis, KTH-3. Moreover, cytokine production of the gamma delta T cell lines was similar to the Th1 pattern [interferon-gamma, tumor necrosis factor (TNF)-alpha and TNF-beta]. They also produced interleukin-8 that functions as one of chemoattractants for polymorphonuclear cells. Using direct sequencing technique of the polymerase chain reaction products, we found that junctional diversity of the T cell receptor (TcR) used by the parental KTH-1 specific gamma delta T cell line and its subclones is rather limited. It is suggested that gamma delta T cells with canonical TcR could preferentially respond to KTH-1 Ag. Thus, in addition to a broad or cross-reactivity of gamma delta T cells against phylogenetically conserved stress/heat-shock protein, which is well characterized by others, some peripheral blood gamma delta T cells could recognize and kill exogenous agents with fine antigenic specificity to protect the body against them.

Antigens, Bacterial↗

Reactive oxygen metabolite-induced toxicity to cultured bovine endothelial cells: status of cellular iron in mediating injury.

We aimed to determine the status of iron in mediating oxidant-induced damage to cultured bovine aortic endothelial cells. Chromium-51-labeled cells were exposed to reaction mixtures of xanthine oxidase/hypoxanthine and glucose oxidase/glucose; these produce superoxide and hydrogen peroxide, or hydrogen peroxide, respectively. Xanthine oxidase caused a dose dependent increase of 51Cr release. Damage was prevented by allopurinol, oxypurinol, and extracellular catalase, but not by superoxide dismutase. Prevention of xanthine oxidase-induced damage by catalase was blocked by an inhibitor of catalase, aminotriazole. Glucose oxidase also caused a dose-dependent increase of 51Ci release. Glucose oxidase-induced injury, which was catalase-inhibitable, was not prevented by extracellular superoxide dismutase. Both addition of and pretreatment with deferoxamine (a chelator of Fe3+) prevented glucose oxidase-induced injury. The presence of phenanthroline (a chelator of divalent Fe2+) prevented glucose oxidase-induced 51Cr release, whereas pretreatment with the agent did not. Apotransferrin (a membrane impermeable iron binding protein) failed to influence damage. Neither deferoxamine nor phenanthroline influenced cellular antioxidant defenses, or inhibited lysis by non-oxidant toxic agents. Treatment with allopurinol and oxypurinol, which inhibited cellular xanthine oxidase, failed to prevent glucose oxidase injury. We conclude that (1) among the oxygen species extracellularly generated by xanthine oxidase/hypoxanthine, hydrogen peroxide induces damage via a reaction on cellular iron; (2) deferoxamine and phenanthroline protect cells by chelating Fe3+ and Fe2+, respectively; and (3) reduction of cellular stored iron (Fe3+) to Fe2+ may be prerequisite for mediation of oxidant-induced injury, but this occurs independently of extracellular superoxide or cellular xanthine oxidase-derived superoxide.

Allopurinol↗

The synergistic antitumor effect of recombinant interleukin-1 and low-dose of cyclophosphamide in tumor-bearing mice.

Intraperitoneal (i.p.) treatment of MOPC104E ascitic tumor-bearing BALB/c mice with interleukin-1 (IL-1) followed by a low dose of cyclophosphamide (CPA) resulted in synergistic prolongation of their survival time. This antitumor effect was abolished when administration of CPA preceded that of IL-1. The combined i.p. therapy also eradicated subcutaneous (s.c.) tumors, indicating a systemically operating antitumor mechanism. In Winn assay, splenocytes from MOPC104E-bearing mice treated with the combined therapy completely suppressed the growth of MOPC104E cells, but not that of another syngeneic tumor cell line, RL female-8 cells. This tumor-neutralizing activity was completely abrogated by treatment with anti-asialo-GM1 or anti-Thy1.2 and complement, and reduced by treatment with anti-Lyt2.2 and complement. Treatment of splenocytes with 1-leucine methyl ester (Leu0Me), which depletes natural killer (NK) cells and macrophages in vitro, did not affect the neutralizing activity.

Animals↗

In situ localization of type III and type IV collagen-expressing cells in human diabetic nephropathy.

Nodular intercapillary glomerulosclerosis is the most typical lesion of diabetic nephropathy (DN) and is characterized by increased extracellular matrix (ECM) and amorphous masses of mesangial matrix. The local exaggeration of these deposits results in the formation of the typical diabetic nodule. To clarify the composition of the ECM of sclerotic lesions in DN, we investigated the distribution of type III and type IV collagens and their mRNAs by immunohistochemistry and in situ hybridization, respectively. In normal renal tissues, there was no intraglomerular immunostaining for type III collagen, while strongly positive staining was found in the extraglomerular interstitium. Positive immunostaining for type IV collagen was also present in the mesangium, glomerular basement membrane (GBM), Bowman's capsule, and the vascular pole of the normal glomerulus. In DN, the nodular lesions were negative for type III collagen and strongly positive for type IV collagen. On the other hand, in the late stage of global sclerosis, both type III and type IV collagens were diffusely present in the sclerotic matrix. To determine the origins of these type III and type IV collagens in the sclerotic matrix, in situ hybridization was performed, utilizing thymine-thymine (T-T) dimerized synthetic oligonucleotides complementary to either pro alpha 1(III) chain or pro alpha 1(IV) chain mRNAs as probes. The signals were detected by enzyme immunohistochemistry using an anti-T-T antibody. Intraglomerular cells (glomerular epithelial and mesangial cells) containing type III collagen mRNA were found in DN with sclerotic lesions, but not in normal glomeruli.(ABSTRACT TRUNCATED AT 250 WORDS)

Collagen↗

An immunohistochemical study of the extracellular matrix in oral squamous cell carcinoma and its association with invasive and metastatic potential.

The expression of extracellular matrices (ECMs) laminin (LN), type IV collagen (IV C), heparan-sulphate proteoglycan (HS-PG), fibronectin (FN), tenascin (TN), decorin and vitronectin (VN) was examined immunohistochemically in 112 primary tumours and 29 metastatic cervical lymph nodes in oral squamous cell carcinoma (OSCC). In highly invasive primary tumours, the expression of LN, IV C and HS-PG in the basement membrane along the tumour-stroma borderline and the expression of decorin and VN in the tumour stroma at the invasive site were all significantly decreased. The expression of FN and TN in the tumour stroma at the same site was markedly increased. In peritumour stroma in metastatic lymph nodes, LN, IV C, HS-PG, decorin and VN were weakly expressed, while FN and TN were strongly expressed. Thus, the staining pattern of the ECMs in the metastatic lymph nodes was similar to that in highly invasive primary tumours. Furthermore, in primary tumours of metastatic cases, the expression of LN, IV C, HS-PG, decorin and VN obviously decreased, while the expression of FN and TN increased when compared with those of the non-metastatic cases. The investigation of ECMs in OSCC was valuable in predicting tumour behaviour.

Carcinoma, Squamous Cell↗

OK-432-combined adoptive immunotherapy as a prognostic factor in peritoneal metastasis from gastric cancer.

Prognostic factors, such as preoperative status, intraoperative findings, and postoperative treatments, were evaluated in 61 patients with peritoneal metastasis from gastric cancer treated in our facility between 1979 and 1991. Since 1986, 23 patients have been treated with OK-432-combined adoptive immunotherapy (AIT). OK-432-combined AIT is a sequential treatment via a catheter inserted into the abdominal cavity, using a streptococcal preparation, OK-432, followed by the transfer of lymphocytes cultured with T cell growth factor and sonicated tumor extract. A univariate analysis showed that six factors consisting of: (1) age, (2) resection of primary lesion, (3) grade of peritoneal metastasis or serosal invasion, (4) chemotherapy, (5) OK-432, and (6) OK-432-combined AIT influenced survival. The survival of the patients given OK-432-combined AIT (median survival time; MST = 7.5 months) was significantly (P = 0.0267) longer than that of those not receiving OK-432-combined AIT (MST = 4.3 months). A multivariate analysis showed that the most significant factors associated with survival were chemotherapy, resection of the primary lesion, and OK-432-combined AIT. Since these three factors are all therapeutic procedures, the use of combination therapy including OK-432-combined AIT is thus expected to prolong the survival of gastric cancer patients with peritoneal metastasis.

Adult↗