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N Kanda

Publications and source records attributed to N Kanda.

At least 37 records · Page 2Linked to original sources
PubMed1999

Anti-alpha-fodrin antibodies in Sjögren syndrome and lupus erythematosus.

OBJECTIVES: To investigate the prevalence of anti-alphafodrin antibody in patients with Sjogren syndrome (SS), lupus erythematosus (LE), or both and the association of this antibody with other clinical manifestations. DESIGN: A study of screening and diagnostic tests. Mean follow-up was 152 months (range, 4-572 months). SETTING: A university hospital associated with a research laboratory in Tokyo, Japan. PATIENTS: Nine patients with primary SS, 15 patients with SS secondary to LE, and 44 patients with LE alone. MAIN OUTCOME MEASURES: Frequencies of clinical and laboratory findings, including anti-alpha-fodrin antibody. RESULTS: Anti-alpha-fodrin antibody was more commonly detected in patients with primary (7/9; P<.001) and secondary (9/15; P<.001) SS than in those with LE alone (3/44). When patients with primary and secondary SS were combined and compared with those with LE alone, the sensitivity of anti-alpha-fodrin antibody was 67%, specificity was 93%, and both positive and negative predictive values were 84%. The presence of anti-alpha-fodrin antibody was associated with pernio, hyperglobulinemia, rheumatoid factor positivity, and the presence of anti-SS-B (La) antibody (P<.01) but not with annular erythema, photosensitivity, vasculitis, or renal disorder. CONCLUSIONS: Although anti-alpha-fodrin antibody was detected in patients with SS and in those with LE, it seemed to be more valuable for the diagnosis of SS than was anti-SS-A (Ro) because anti-alpha-fodrin was much less prevalent in patients with LE alone. It may be possible to consider this novel autoantibody as pathophysiologically associated with some extraglandular manifestations characteristically seen in patients with SS.

Adolescent↗
PubMed1999

Estrogen enhancement of anti-double-stranded DNA antibody and immunoglobulin G production in peripheral blood mononuclear cells from patients with systemic lupus erythematosus.

OBJECTIVE: To study the in vitro effect of estrogen on IgG anti-double-stranded DNA (anti-dsDNA) antibody and total IgG production in peripheral blood mononuclear cells (PBMC) from patients with systemic lupus erythematosus (SLE), in order to elucidate its regulatory role in SLE. METHODS: PBMC from SLE patients and normal donors were cultured with 17beta-estradiol (E2). IgG anti-dsDNA antibodies, total IgG, and cytokine activity in the culture supernatants were measured by enzyme-linked immunosorbent assay. RESULTS: E2 enhanced production of IgG anti-dsDNA antibodies as well as total IgG in PBMC from SLE patients. Anti-dsDNA production in patients with inactive disease was less responsive to E2 than that in patients with active disease. E2 also enhanced total IgG, but not anti-dsDNA, production in the PBMC of normal donors. Antibody production was increased by E2 to a lesser extent in patients' B cells than in their PBMC. Anti-interleukin-10 (anti-IL-10) antibodies partially blocked the E2-induced increase in antibody production in patients' PBMC, but anti-IL-10 had no effect on B cells. E2 increased IL-10 production by patients' monocytes. Exogenous IL-10 acted additively with E2 in increasing antibody production in patients' B cells. CONCLUSION: These results suggest that E2 may polyclonally increase the production of IgG, including IgG anti-dsDNA, in SLE patients' PBMC by enhancing B cell activity and by promoting IL-10 production in monocytes. These findings support the involvement of E2 in the pathogenesis of SLE.

Adult↗
PubMed1999

Estrogen enhances immunoglobulin production by human PBMCs.

BACKGROUND: It has been suggested that estrogen may enhance humoral immune responses and may be involved in the pathogenesis of autoimmune diseases. OBJECTIVE: We studied the in vitro effects of 17beta-estradiol (E2 ) on spontaneous immunoglobulin production by human PBMCs. METHODS: PBMCs from healthy human volunteers were cultured with E2. Levels of IgG and IgM and cytokine activity were measured by ELISA. Proliferation was determined by [3H]-thymidine uptake. The cell viability was assessed by a trypan blue exclusion test. RESULTS: E2 enhanced IgG and IgM production of PBMCs both from men and women without altering cell viability and proliferation. The stimulatory effect of E2 was revealed at 10(-10) mol/L, increased in a dose-dependent fashion, and was maximized at 10(-8) mol/L. IgG production of PBMCs in the presence of E2 (10(-8) mol/L) was 220% of control cells, and that of IgM was 211%. Immunoglobulin production of E2 -treated B cells was slightly higher than that of control cells; IgG production was 161% of control cells, and that of IgM was 157%. Anti-IL-10 antibody partially blocked the E2 effect on immunoglobulin production of PBMCs; anti-IL-10 reduced IgG production in the presence of E2 from 206% to 154% of control cells, and that of IgM from 206% to 152%. E2 increased IL-10 production of monocytes up to 250% of control level, but it did not affect that of T cells or B cells. Exogenous IL-10 (1 U/mL) further enhanced E2 -induced increase of immunoglobulin production by B cells, although this level of IL-10 alone was ineffective for B cells. CONCLUSION: These results suggest that E2 may increase immunoglobulin production of human PBMCs mainly by increasing IL-10 production of monocytes. The results also support that E2 may act as an important stimulator for human humoral immunity.

Adjuvants, Immunologic↗
PubMed1999

Ganglioside GD1b supresses immunoglobulin production by human peripheral blood mononuclear cells.

Gangliosides are sialic acid-containing glycolipids, that have various immunomodulatory effects. We previously reported that various gangliosides in vitro either inhibited or enhanced spontaneous immunoglobulin (Ig) production by human peripheral blood mononuclear cells (PBMC). GD1b was one of the inhibitory gangliosides. In this study, we further examined the mechanism for the inhibitory effect of GD1b. The inhibitory effect of GD1b was revealed at 0.1 microM, increased dose dependently, and was maximized at 10 microM, which reduced spontaneous IgG, IgM, and IgA production of human PBMC by 50.5%, 52.0%, and 48.3% compared with controls, respectively. GD1b did not affect the proliferation and viability of PBMC. GD1b did not alter Ig production of B cells alone. Interleukin 6 (IL-6) and IL-10 each partially reversed the GD1b-induced inhibition of Ig production by PBMC, and the addition of both cytokines completely reversed the inhibition. When endogenous IL-6 and IL-10 were neutralized by specific antibodies, GD1b did not reveal inhibitory effects on the Ig production. GD1b inhibited IL-6 and IL-10 production of CD4+ T cells, without affecting those of CD8+ T cells, monocytes, or B cells. When CD4+ T cells were preincubated with GD1b and washed and cultured with B cells and monocytes, Ig production was also suppressed. These results suggest that GD1b may indirectly suppress Ig production of B cells in whole PBMC by reducing IL-6 and IL-10 production of CD4+ T cells. GD1b may act as an important inhibitor of human humoral immune responses.

Adult↗
PubMed1999

Ganglioside GT1b suppresses immunoglobulin production by human peripheral blood mononuclear cells.

Gangliosides are sialic acid-containing glycolipids and have various immunomodulatory effects. We previously reported that various gangliosides in vitro either inhibited or enhanced spontaneous immunoglobulin production by human peripheral blood mononuclear cells (PBMC). Among them, GT1b was the most inhibitory. In this study, we further examined the mechanism for the inhibitory effect of GT1b. The inhibitory effect of GT1b was apparent at 0.1 micrometers, increased dose dependently, and was maximal at 10 micrometers. In the presence of 10 micrometers GT1b, spontaneous production of immunoglobulin (Ig)G, IgM and IgA in human PBMC was reduced by 60%, 59.5% and 58%, respectively, compared with controls. GT1b did not affect the proliferation and viability of PBMC, and did not enhance their apoptosis. GT1b did not alter immunoglobulin production of B cells alone. Interleukin (IL)-6 and IL-10 each partially reversed the GT1b-induced inhibition of immunoglobulin production by PBMC, and the presence of both cytokines completely reversed the inhibition. GT1b inhibited IL-6 and IL-10 production in monocytes, without affecting that in T or B cells. When monocytes were preincubated with GT1b, washed and then cultured with B and T cells, the immunoglobulin production was also suppressed. These results suggest that GT1b may indirectly suppress immunoglobulin production of B cells in whole PBMC via reducing the production of IL-6 and IL-10 in monocytes. It is thus indicated that GT1b may act as an important inhibitor for human humoral immune responses.

Cell Culture Techniques↗
PubMed1998

Inhibition of P-glycoprotein and recovery of drug sensitivity of human acute leukemic blast cells by multidrug resistance gene (mdr1) antisense oligonucleotides.

To overcome the problem of multidrug resistance, we investigated the effectiveness of phosphrothioate antisense oligonucleotides (MDR1-AS) in suppressing multidrug resistance gene (mdr1) expression in drug-resistant acute myelogenous leukemia (AML) blast cells and the K562 adriamycin-resistant cell line K562/ADM. The percentage of cells with the mdr1 gene product P-glycoprotein (P-gp) was decreased from 100% to 26% by 20 micromol/L MDR1-AS in the K562/ADM cells, and from 48.1% to 10.2% by 2.5 micromol/L MDR1-AS in the AML blast cells. Western blot analysis also showed a decrease in the amount of P-gp in the MDR1-AS-treated K562/ADM cells. This effect was specific to MDR1-AS, and not observed with sense or random control oligonucleotides. The expression of mdr1 mRNA in K562/ADM and AML blast cells treated with MDR1-AS was decreased compared with the random control. Intracellular rhodamine retention and [3H]daunorubicin also increased after antisense treatment. Chemosensitivity to daunorubicin increased in MDR1-AS-treated blast cells up to 5.9-fold in the K562/ADM cells and 3.0- to 6.4-fold in the AML blast cells. The expression of mdr1 mRNA derived from colony cells decreased in the MDR1-AS-treated groups. No inhibitory effect of the oligonucleotides on normal bone marrow progenitors was observed. These findings suggest that MDR1-AS is useful to overcome multidrug resistance in the treatment of leukemia.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1998

Ganglioside GQ1b enhances Ig production by human PBMCs.

BACKGROUND: Gangliosides are glycosphingolipids that contain sialic acid and have various immunomodulatory effects. OBJECTIVE: We studied in vitro effects of gangliosides on human humoral immune responses. METHODS: PBMCs from healthy volunteers were cultured with gangliosides GM1, GM2, GM3, GD1a, GD1b, GD2, GD3, GT1b, and GQ1b. The amounts of IgG, IgM, and IgA and cytokine activity in the culture supernatants were measured with use of an ELISA. Proliferation was determined by [3H] thymidine uptake. RESULTS: Among the various gangliosides tested, GQ1b most strongly enhanced spontaneous IgG, IgM, and IgA production by human PBMCs. The effect of GQ1b was revealed at 0.1 micromol/L, increased dose dependently, and was maximized at 10 micromol/L. Weaker but significant stimulatory effects on the Ig production were manifested by GM2 and GD1a, whereas GT1b and GD1b were inhibitory. None of the gangliosides examined affected the proliferation of PBMCs. GQ1b did not enhance Ig production of B cells alone. Anti-IL-6 and anti-IL-10 antibody each partially blocked GQ1b-induced enhancement of the Ig production by PBMCs, and the addition of both antibodies completely blocked the enhancement. GQ1b enhanced both IL-6 and IL-10 production of T cells without affecting those of monocytes or B cells. GQ1b enhanced Ig production of T and B cell culture without monocytes. When T cells were preincubated with GQ1b, washed and added to B cells and monocytes, and then cultured together, the Ig production was also enhanced, although to a lesser extent than the whole time incubation. Exogenous IL-6 and IL-10 each enhanced Ig production of B cells alone, and the addition of both gave additive effects. CONCLUSION: These results suggest that GQ1b may indirectly enhance Ig production of B cells by promoting IL-6 and IL-10 production of T cells in whole PBMC culture. That GQ1b may act as an important immunostimulator is also indicated.

Antibodies, Anti-Idiotypic↗
PubMed1998

A functional thyrotropin- and growth hormone-secreting pituitary adenoma with a ultrastructurally monomorphic feature: a case study.

A 38-yr-old female with a TSH- and GH-secreting pituitary adenoma is described, who had both overt symptoms, hyperthyroidism and acromegaly. Her serum TSH was not suppressed despite high concentrations of free T3 and free T4, and her alpha-subunit/TSH molar ratio was high. Her serum GH was consistently high, and was not suppressed by an oral glucose tolerance test. Preoperative testing revealed that, although the TSH response was impaired, TSH, alpha-subunit and GH were increased by TRH injection, and that these hormones were reduced by bromocriptine or somatostatin analog. Although she did not have hyperprolactinemia, the in vitro culture and immunohistochemical studies revealed that the adenoma cells produced and released PRL, in addition to TSH, alpha-subunit and GH. Immunohistochemical studies showed the presence of GH in the cytoplasm of many adenoma cells. TSH beta-positive adenoma cells were less frequently seen than GH-positive adenoma cells. No cells showed the coexistence of GH and TSH beta, and a few cells were positive for PRL. By electron microscopy, the adenoma was found to be composed of a single cell type resembling thyrotrophs, and did not have any characteristics of somatotrophs. This case was considered to be of interest, because the adenoma was ultrastructurally monomorphous, but immunohistochemically polymorphous.

Acromegaly↗
PubMed1998

[Right-to-left shunt and atrial septal aneurysm in stroke patients: a contrast transesophageal echocardiographic study].

BACKGROUND: Transesophageal echocardiography (TEE) has been used to detect cardiac abnormalities including right-to-left shunt (RLS) and atrial septal aneurysm (ASA). The aim of this study was to elucidate frequency of RLS and ASA detected by contrast-TEE, and to evaluate the role of these abnormalities in stroke patients. METHODS AND RESULTS: We investigated prevalence of RLS and ASA in 504 patients suspected of stroke by using TEE. (mean age 62 +/- 12 y.o., stroke 491, non-stroke 13). The RLS was detected in 64 patients (12.7%), in whom 49 patients (9.7%) had the patent foramen ovale (PFO). The ASA was demonstrated in 10 patients (2.0%), and accompanied well with the RLS (six of the 10, 60%). The prevalent ratios of the RLS (33.8%), the PFO (26.8%), and the ASA (11.3%) in 71 patients with embolic stroke (brain embolism or TIA) of unknown cause were significantly higher than those in the other 433 patients (9.2%, 6.9%, 0.5%, respectively, p < 0.0001). Multiple logistic regression analysis showed that both the PFO and the ASA were independent risk factors (odds ratio: 3.8: p = 0.0002 and 16.6: p = 0.0008, respectively) for embolic stroke of unknown cause. CONCLUSION: It seems that the RLS, PFO and the ASA play a roll in developing embolic stroke of unknown cause.

Adult↗
PubMed1997

Enrichment of oligo(dG).oligo(dC)-containing fragments from human genomic DNA by Mg 2+-dependent triplex affinity capture.

Oligo(dG).oligo(dC)- or short poly(dG).poly(dC)-containing fragments were enriched and cloned by means of Mg2+-dependent triplex affinity capture and subsequent cloning procedures. A library constructed after three cycles of enrichment showed that approximately 80% of the clones in the supercoiled form formed a complex with labeled oligonucleotide (dG)34. However, while the rest of the clones retained the ability to form a complex (type I clones), 90.9% failed to form a complex when they were linearized. This group of DNA was abundant in the genomic DNA, although it showed only approximately 3-fold enrichment by one cycle of affinity capture. This group was further classified into two species (types II and III) based on complex formation ability after phenol extraction. Type II clones retained the complex formation ability after treatment, while the human telomere [(TTAGGG)n] and telomere-like [(TGGAA)n] or [(TGGAG)n] sequences belonging to type III clones did not. Serial deletion experiments and the binding assays using oligonucleotides confirmed that the repetitive units containing T(G)nT ( n = 3-5) tracts or (G)n-motifs (n >/= 3) were the sites of complex formation for type II and III clones. On the other hand, type I clones contained poly(dG).poly(dC) tracts at least 10 nt long, and DNase I-footprinting analysis indicated that these tracts were the sites of complex formation.

Cloning, Molecular↗
PubMed1997

Autosomal dominant early onset dementia and leukoencephalopathy in a Japanese family: clinical, neuroimaging and genetic studies.

We report here the results of clinical, neuroimaging and genetic studies of autosomal dominant dementia and leukoencephalopathy in a Japanese family. Twenty-two individuals in this family were examined clinically (17 living, 5 deceased), neuroradiologically and genetically (16 of 17 living members). Ten (5 deceased) of 22 individuals had early onset dementia (age of onset: 45.2 +/- 12.1 years on average) and four of them had multiple white matter lesions and brain atrophy on brain MRI without history of brain ischemic attack. Another four individuals had abnormal white matter lesions on brain MRI without dementia. Linkage studies for chromosome 1q31-42, 14q24.3 and 21q21 responsible for Alzheimer's disease, chromosome 19p13.1-13.2 for cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and chromosome 3 for familial non-specific dementia suggested no specific haplotypes cosegregated with the disease. Apo E genotypes were E2/2 and E2/3 in this family. Clinical, neuroimaging and genetic studies revealed that the disease in this family was distinguished from known familial dementia. This is the first report of a large Japanese family with autosomal dominant early onset dementia and leukoencephalopathy.

Adult↗
PubMed1997

Cell cycle-dependent activation of telomerase in naturally synchronized culture of a true slime mold, Physarum polycephalum.

Telomeres of Physarum plasmodia did not shorten with numerous repeats of nuclear division, and an apparent activity of telomerase was detected in this organism. In naturally synchronized culture of Physarum plasmodia, an evident activation of telomerase was observed at the late S-phase, just prior to the completion of in vivo DNA replication, and the low telomerase activity was detected throughout the cell cycle. In the nuclei isolated from different phases of synchronized plasmodia, a higher activity of telomerase was also observed at late S-phase. These results clearly show the existence of a cell cycle-dependent regulatory mechanism of telomerase activity in growing, naturally synchronized cells.

Animals↗
PubMed1997

Testosterone suppresses anti-DNA antibody production in peripheral blood mononuclear cells from patients with systemic lupus erythematosus.

OBJECTIVE: To study the in vitro effect of testosterone on anti-DNA antibody production in peripheral blood mononuclear cells (PBMC) from patients with systemic lupus erythematosus (SLE) in order to elucidate its regulatory role in SLE. METHODS: PBMC from SLE patients were cultured with testosterone. IgG anti-double-stranded DNA (anti-dsDNA) antibody, total IgG, and cytokine activity in the supernatants were measured by enzyme-linked immunosorbent assay. RESULTS: Testosterone suppressed both IgG anti-dsDNA antibody and total IgG production in PBMC from SLE patients. Antibody production in B cells was also suppressed by testosterone, although the magnitude of its effect on B cells was lower than that on PBMC. Interleukin-6 (IL-6) partially restored the testosterone-induced decrease in antibody levels in PBMC. Testosterone reduced IL-6 production in monocytes. CONCLUSION: These results suggest that testosterone may directly suppress anti-DNA antibody production in PBMC from SLE patients by inhibiting B cell hyperactivity and, indirectly, by down-regulating IL-6 production in monocytes. These results support the therapeutic effects of testosterone on SLE.

Adult↗
PubMed1997

Annular erythema associated with lupus erythematosus/Sjögren's syndrome.

BACKGROUND: Annular-polycyclic and papulosquamous lesions are associated with subacute cutaneous lupus erythematosus (SCLE). In some Asian cases, annular erythema has been associated with Sjögren's syndrome (SS). However, the relation between the two is unclear. OBJECTIVE: Our purpose was to clarify the clinical manifestations and immunologic features of patients with annular erythema. METHODS: This study included 15 patients with annular erythema. Systemic, serologic, and genetic findings were analyzed. RESULTS: Histologic examination showed perivascular and periappendageal lymphocytic infiltrates in all patients. However, LE-specific epidermal changes were observed in only three (20%). Although all patients at least partially demonstrated features of LE or SS, eight (53%) fulfilled the American Rheumatism Association criteria for systemic LE (SLE) and five (33%) were diagnosed with SS. Renal (20%) and central nervous system (7%) involvement was observed. Anti-Ro(SS-A) and anti-La(SS-B) antibodies were detected in nine (60%) and seven (47%) patients, respectively. There were no histocompatibility antigen (HLA) haplotype differences. CONCLUSION: Annular erythema in Asian patients is the counterpart of subacute skin lesions of LE in whites, except for the paucity of LE-specific histopathologic findings and HLA-DR3 tissue type.

Adolescent↗
PubMed1997

Identification and characterization of a major lysosomal membrane glycoprotein, LGP85/LIMP II in mouse liver.

We previously have purified and characterized a major lysosomal membrane glycoprotein termed LGP85 (LIMP II) in rat liver lysosomes. In this study, LGP85 in mouse liver lysosomes was identified and characterized by biochemical and molecular biological methods. Lysosomal membranes were isolated from murine liver by differential centrifugation. LGP85 was present in the lysosomal membrane fraction from mouse liver in a comparable amount to another lysosomal membrane glycoprotein, lamp-2. Mouse LGP85 (M-LGP85) from liver lysosomal membranes exhibited an Mr of 80,000 on SDS-PAGE, which is smaller by 5,000 than that of rat LGP85 (R-LGP85). M-LGP85 was immunochemically detected in the extracts of brain, heart, lung, liver, and kidney. A cDNA encoding M-LGP85 was cloned from mouse liver cDNA library. The primary protein structure deduced from a nucleotide sequence of M-LGP85 cDNA indicated that M-LGP85 consists of 478 amino acids with Mr of 54,069. M-LGP85 showed 93.3 and 86.0% sequence similarities to its rat and human counterparts in amino acids, respectively. M-LGP85 contains 11 potential N-glycosylation sites which are heavily glycosylated, resulting in the increased Mr of M-LGP85 present in the mouse liver lysosomes. It is likely that M-LGP85 traverses the lysosomal membrane twice, with an NH2-terminal transmembrane domain, and another hydrophobic domain near the COOH-terminus. M-LGP85 has a protruding COOH-terminal cytoplasmic tail consisting of amino acid residues including the leucine-isoleucine sequence shown to be the lysosomal targeting signal of R-LGP85 and human LGP85 (H-LGP85). The high level of expression of M-LGP85 in the lysosomal membrane, the high structural similarities among M-, R-, and H-LGP85, and the occurrence of M-LGP85 in all the mouse tissues examined suggest the essential and constitutive function of LGP85 in lysosomes.

Amino Acid Sequence↗
PubMed1997

Cutaneous lupus mucinosis: a review of our cases and the possible pathogenesis.

Cutaneous lupus mucinosis (CLM) is a rare variant of lupus erythematosus eruptions. Our 5 cases with CLM were reviewed. All were men with systemic lupus erythematosus (SLE). CLM occurred as asymptomatic cutaneous papules, nodules, or plaques on the trunk, upper and lower extremities, and face. Histopathology of CLM mainly revealed abundant mucin deposits among splayed collagen bundles throughout the dermis. However, some CLM lesions showed discoid lupus erythematosus-like epidermal and dermal changes and/or lupus profundus. Vasculitis was also revealed in the CLM lesions of 2 cases. The pathogenesis of CLM may be closely related to its two important features, the male preponderance and the association with SLE. Vasculopathy may also be involved in the development of CLM.

Adult↗