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S Sekiguchi

Publications and source records attributed to S Sekiguchi.

At least 181 records · Page 10Linked to original sources
PubMed1990

[Steroid withdrawal in renal transplant recipients].

The clinically important side effects of long-term steroid use are well known. We report the results of complete steroid withdrawal in 7 living-related renal transplants in HLA-identical (3) or one-haplotype match (4) recipients initially treated with azathioprine (5) or cyclosporine (2), and steroids. After the end of the second year, steroids were stopped if renal function was normal (serum creatinine below 2.0 mg/dl) and if no alterations were seen on renal biopsy. In 1 patient steroid had to be discontinued because of the complications of steroid immunosuppression. The study population consisted of 7 patients with a mean age of 32.4 years. The sex distribution was 6 males and 1 female. All patients had received a minimum of 3 blood transfusions prior to transplantation. Steroid was discontinued 34.0 +/- 18.1 months posttransplant. Oral azathioprine or cyclosporine were employed for long-term maintenance immunosuppression. Six patients (86%) have remained continuously off steroids for 52.2 +/- 50.5 months (range 4-150) with stable renal function. The mean serum creatinine was 1.1 +/- 0.4 mg/dl at the most recent follow-up. Reinstitution of steroid was required in 1 patient (14%) for rejection (36 months after steroid withdrawal). Thus, steroid withdrawal was successful in 6 of 7 patients. In HLA-identical recipients, all are currently steroid-free. In haplo-matched patients, 75% are steroid independent. Discontinuation of steroid resulted in a decrease in serum cholesterol concentration from 246 +/- 41 to 204 +/- 25 mg/dl (P less than 0.003). We conclude that steroid withdrawal may be accomplished in selected patient without increasing the rate of graft loss.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Laboratory tests in primary care medicine: "essential laboratory tests" (1). Urinalysis].

Japan Society of Clinical Pathology has formed a committee dealing with "lab. tests in primary care medicine". As the first step, they made "Essential Lab. Tests" which were composed of simple qualitative bed-side tests such as urinalysis, Complete blood count (CBC: Hb, Ht, WBC, RBC), CRP, or ESR (Erythrocyte sedimental rate), A/G ratio and biochemical tests if necessary (Table 1). We have performed "Essential Lab. Tests" on 1,026 outpatients who visited General Medicine Clinic for the first time. They consisted of 456 male (age 13-81), and 526 female (age 10-85). This report is the result of urinalysis from "Essential Lab. Tests" of 1,026 patients. 1) The result showed that overall positivity of the urinalysis was 21.3% (when more than one item of the qualitative tests was positive). 2) There was distinctive difference in the positivity of the urinalysis between the sex; i.e. protein and glucose were about twice frequently positive in male, where as occult blood and WBC (Esterase reaction) were 2-3 times more positive in female. 3) Urine protein shows positive in the individual 10-20 yrs old and more than 50 yrs old in both sexes. 4) Glucose was positive in over 40 yrs in male, and occult blood, 40-50 yrs or older in male. 5) WBC shows positive in all age groups in female and 50 yrs or older in male. 6) Positive WBC patients did not necessarily reflect urinary infection in female but nitrites roughly corresponded with urinary WBC in male of 50 yrs or older, meaning probable urinary infection associated with prostatic hypertrophy. 7) Abnormality of urinary sediment corresponded to the positive occult blood and WBC Erastase. 8) Urinalysis is an useful method of screening in primary care medicine.

Adolescent↗
PubMed1990

Crohn's disease in the Japanese is associated with the HLA-DRw53.

The association of Crohn's disease (CD) with the HLA system was investigated in Japanese patients by serological and genomic methods. HLA antigens were typed in 30 unrelated Japanese patients with CD and 54 healthy controls. The frequencies of HLA-DR4, DRw53 and DQw3 antigens were increased in CD (76.7, 86.7 and 80.0%) compared with controls [37.0%, p corrected (pc) = 0.007; 52.9%, pc = 0.001; 52.0%, pc = 0.009]. DQw7 and DQw8 antigens, the new split antigens of DQw3 produced by the TA10 antibody and linked to the DR4 and DRw53 antigens, were not significantly different in the DQw3-positive CD and controls. Class I antigens were not significantly different in the CD and controls. HLA-DR-B and DQ-B probes were used to study PstI-generated restriction fragment length polymorphism (RFLP) in CD and controls. The DRw53-specific PstI DR-B 2.6-kb fragment was increased in CD (88.0%) compared with controls (37.5%, pc = 5.6 X 10(-4)). The PstI DR-B 3.2-kb fragment was also increased in CD (80.0%) compared with controls (35.0%, pc = 5.6 X 10(-3)). It is reasonable to infer that the DRw53 is the most important susceptibility antigen in Japanese CD. The subtypes of the DR4 were determined by the hybridization of the DQ-B probe. The DQ-B PstI fragment patterns were not different in CD and controls.

Biomarkers↗
PubMed1990

[Immunogenetic factors influencing HBV carrier state, the seroconversion and the development of chronic liver disease].

In order to investigate the immunogenetic factors associated with hepatitis B virus (HBV) carrier state, the HBe seroconversion and the development of chronic liver disease, HLA typing were performed in 278 asymptomatic HBV carriers (ASC) and 110 patients with chronic B type hepatitis (CH). HLA typing was also performed in 178 vaccinees who had received hepatitis B vaccine. The significantly decreased frequencies of DR1 and DRw13 were found in ASC, CH and non-responders to HB vaccine. This suggests that DR1 and DRw13 may be associated with the elimination of HBV. The frequency of DR4.2 was increased in ASC, but decreased in CH. The seroconversion rate of DR4.2 positive CH as well as ASC was high. Therefore DR4.2 may have relevance to the seroconversion from HBeAg to anti-HBe.

Carrier State↗
PubMed1990

[Proffered opinion forum medical decision making, impact on laboratory tests].

Raising medical expenditure is a universal problem. The Japanese government started taking measures not to increase medical expenses in the recent years. Laboratory tests are no exception. Therefore we as clinical pathologists have reevaluated laboratory tests from the primary care situations to more advanced stages of clinical medicine. As the first step, we formed a subcommittee to effective by utilize laboratory tests and agreed to establish the "essential lab tests". Essential lab tests are made of qualitative bed side tests (type I) and slightly advanced tests (type II) and these tests are to be done on every patient at their first clinic visit. These tests are also to be performed parallel to physical examination and history-taking. The results revealed 50% and 90% positivities on the type I and type II tests, which indicate rather effective means for making an initial impression.

Adolescent↗
PubMed1989

Evaluation of the human T-cell leukemia virus type I seropositivity of blood donors by the particle agglutination inhibition test.

In the HTLV-I seroscreening of blood donor sera by gelatin particle agglutination (PA), more than 50% (55.6%) of the PA-positive sera were negative by immunofluorescence assay (IF). However, when donors were divided into age groups, there were increasing numbers of IF-positive/PA-positive donors with age. Among the PA-positive donors in the 50-64 age group, 65.9% were IF-positive compared to 16.0% in the 16-19 age group. The serological specificities of the IF-negative/PA-positive specimens were tested by using a newly developed PA inhibition (PAI) test. The HTLV-I specificity of the PAI test was confirmed by the observation that agglutinations with anti-HTLV-I p19 and gp21 monoclonal antibodies as well as IF-positive sera were specifically inhibited with HTLV-I preparations or HTLV-I-positive cell extracts and not with HTLV-I-negative cell extracts. Sixty of the 104 specimens collected randomly from the IF-negative/PA-positive donors were PAI-positive. The majority (80%) of such PAI-positive sera showed more than two bands of HTLV-I gag-encoded polypeptide, p19, p24, p28 and p53 on Western blotting. Some of the PAI-positive sera were also positive by enzyme immunoassay. These results indicate that at least some of the IF-negative/PA-positive donors possess HTLV-I-specific antibody and may be potential HTLV-I carriers who will become IF-positive at a later age.

Adolescent↗
PubMed1989

A new platelet-specific antigen, Naka, involved in the refractoriness of HLA-matched platelet transfusion.

Serum from a thrombocytopenic patient who was refractory to the transfusions of HLA-matched platelets contained a platelet-specific alloantibody, anti-Naka. Immunofluorescence analyses revealed that the Naka antigen defined by the serum was expressed exclusively on platelets and its distribution was different from P1A1, Baka, Yuka or Yukb. Analysis by Dr. von dem Borne's group revealed the Naka was also different from Koa, Kob or Zwb. Family studies showed that the Naka antigen was inherited as an autosomal codominant trait. Its antigen frequency in the Japanese population was over 97%. The results of the enzyme immunoassay using monoclonal antibodies for antigen immobilization showed that the Naka epitope did not appear to reside on GPIIb/IIIa or Ib. The transfusions of Naka-compatible platelets improved the patient's thrombocytopenia.

Adult↗
PubMed1989

Synergistic enhancement of class I major histocompatibility complex antigen expression in K562 cells induced by recombinant human interferon-gamma and tumor necrosis factor in combination.

The effects of recombinant preparations of human interferon-gamma (rIFN-gamma) and tumor necrosis factor (rTNF), alone or in combination, on class I or class II major histocompatibility complex (MHC) antigen induction were studied using K562, a multipotent hematopoietic precursor cell line. Class I antigens were weakly induced by rIFN-gamma; however, rTNF at any concentration examined (1-1000 U/ml) showed no effect on the induction of class I or class II antigens in the cells. rIFN-gamma (600 U/ml) induced approximately 20% of the cells to express class I antigens after 72-h exposure, whereas 81% of the cells demonstrated class I antigens on their cell surfaces when the cells were simultaneously exposed to 600 U/ml of rIFN-gamma and 1000 U/ml of rTNF. The class II MHC antigens were not induced by the treatments with rIFN-gamma or rTNF, alone or in combination. A synergistic increase of mRNA for class I MHC molecules was demonstrated by treatments of the cells with rIFN-gamma and rTNF in combination. rTNF, but not rIFN-gamma, weakly induced granulocyte-monocyte antigens on the cell surface; however, no synergism was observed on the induction of these antigens by the combined treatments with rIFN-gamma and rTNF. These results indicate that class I MHC antigen expression on K562 cells can be induced by IFN-gamma in cooperation with TNF in a manner different from myeloid antigen expression.

Dose-Response Relationship, Drug↗
PubMed1988

A rapid method for the isolation of functional human T lymphocytes using hydroxyapatite column fractionation.

Passage of peripheral blood lymphocytes through a column of hydroxyapatite resulted in a 7-20-fold depletion of immunoglobulin-bearing cells, a 20-fold depletion of monocytes, and a 1.3-fold enrichment of T cells. The effluent population was virtually devoid of B lymphocyte precursors and monocytes, whereas helper cell and suppressor cell populations remained intact. This method will facilitate the rapid preparation of T-enriched cell populations.

B-Lymphocytes↗
PubMed1988

Phorbol ester enhances morphological differentiation of oligodendrocytes in culture.

The effects of phorbol esters have been attributed to the activation of the enzyme protein kinase C. While much has been described for the actions of phorbol esters on neurons and synaptic transmission, sparse data exist on the effects of phorbol esters on oligodendrocytes, the cells that make and maintain myelin in the central nervous system. In this report, we show that 10 and 100 nM of a phorbol ester, 4 beta-phorbol-12,13-dibutyrate, extensively enhanced process formation by cultured bovine oligodendrocytes. This effect was blocked by two inhibitors of protein kinase C, sodium heparin and polymixin B. We propose the hypothesis that activation of protein kinase C is an important process that leads to the differentiation of oligodendrocytes and the formation of myelin in vivo.

Animals↗
PubMed1988

Preparation of virus-free pyridoxylated hemoglobin from the blood of HBV or HTLV-I healthy carriers.

One of our major aims was to find ways to utilize outdated or virus-contaminated blood. Pyridoxylated hemoglobin (PLP-Hb), a possible substitute for red cells as an artificial oxygen carrier was prepared from outdated human blood. By conjugation with polyethylene glycol (PEG), the biological half life was increased about 3 folds at 82% blood replacement in rats without significant side effects in vivo or in vitro. We next tried to prepare virus-free PEG-PLP-Hb from HBV or HTLV-I positive blood. A considerable amount of HBV (Dane particles) could be removed from HBV-positive red cells by washing and during the preparation of PEG-PLP-Hb. When the hemoglobin preparations containing Dane particles were filtered through a porous cellulose filter, BMM-30 (30 nm pore size, Asahi Chemical Industry Co., Ltd., Osaka, Japan), HBV-DNA in the filtered fractions became less than 0.33% of the initial amount. More than 96% of blood leukocytes could be removed with a leukocyte removal filter, Sepacell R-500 (Asahi Medical Co., Ltd., Tokyo, Japan). The leukocytes collected from filtrated fractions of HTLV-I positive blood did not survive beyond 3 days. Since transmission of HTLV-I occurs by cell to cell contact and is rare in cell-Free condition, it is unlikely that the PLP-Hb prepared from HTLV-I positive blood which is deprived of leukocytes transmits HTLV-I infection.

Animals↗
PubMed1988

Effect of hypophysectomy on 17 alpha-hydroxylase activity in theca cells of the ovarian follicle in the Japanese quail.

The activity of 17 alpha-hydroxylase, a key enzyme for progesterone metabolism in avian follicles, was measured in cell-free homogenates of isolated theca cells of Japanese quail. Kinetic studies revealed that differences in enzyme activity in the largest and the second largest follicles were mainly due to differences in Vmax values. In order to investigate the mechanism of regulation of 17 alpha-hydroxylase activity, quail were hypophysectomized at various time periods during the ovulatory cycle, and 17 alpha-hydroxylase activity in theca homogenates was measured 4 h after surgery. Hypophysectomy at 8 h before the predicted time of ovulation, which is the time when the preovulatory luteinizing hormone (LH) surge is initiated, resulted in a significant decrease in enzyme activity. In contrast, activity was increased when the pituitary was removed 20 h before ovulation. Hypophysectomy 24 h before ovulation had no effect on enzyme activity.

Animals↗