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Biomedical subjects

Y Ohmoto

Publications and source records attributed to Y Ohmoto.

At least 109 records · Page 6Linked to original sources

[Prevention of MRSA spread in the neurosurgical field].

We investigated the distribution of MRSA (methicillin-resistant Staphylococcus aureus) on and around six patients with MRSA infection in our neurosurgical ward. All patients had a disturbance of consciousness and had sputum colonization of MRSA. Samples were obtained from 11 sites (patients' hands, attendances' hands, floors, sidetables, bedclothes, chairs, walls, curtains, door knobs, faucets and disposable gloves) in the patients' rooms by the wiping method. High counts of MRSA were detected on horizontal planes such as floors, sidetables and chairs, but MRSA was not detected on vertical planes such as curtains and walls. The reason why MRSA was detected on the horizontal planes was due to a fall of MRSA spread from sputum in the air. These findings indicate that the disinfection of horizontal planes is important for preventing the spread of MRSA. We also evaluated what disinfectant was useful for floor disinfection and concluded that 0.5% chlorhexidine digluconate (Hibitane) and 0.5% benzalkonium chloride (Osvan) were more effective than the other usually-used disinfectants such as alkyldiaminoethyl glycine (Tego-51).

Adult↗

Systemic chemotherapy alters interleukin-1 beta and its receptor antagonist production by human alveolar macrophages in lung cancer patients.

The purpose of this study was to determine whether cytotoxic chemotherapy influences the number and function of alveolar macrophages (AM) in patients with lung cancer. AM were obtained by bronchoalveolar lavage from 24 patients with lung cancer and 17 control patients. The functional integrity of AM was determined by their ability to produce interleukin-1 beta (IL-1 beta) and interleukin-1 receptor antagonist (IL-1ra) before and after platinum-containing systemic chemotherapy. The productions of IL-1 beta and IL-1ra were quantitated by enzyme immunoassays. The proportions of multinucleated cells among AM were significantly decreased after systemic chemotherapy in lung cancer patients. No significant difference in spontaneous and lipopolysaccharide (LPS)-stimulated IL-1 beta or IL-1ra production by AM was observed between lung cancer patients and control patients. Significant increase of IL-1 beta and significant decrease of IL-1ra production by AM were demonstrated in patients with small cell lung cancer who experienced response to systemic chemotherapy. These results suggest that systemic chemotherapy may influence functional roles of AM in the lung, and consideration of influence of systemic chemotherapy on host functions is important in cancer treatment.

Adult↗

The correlation of thymidine phosphorylase activity with the expression of interleukin 1 alpha, interferon alpha and interferon gamma in human colorectal carcinoma.

Thymidine phosphorylase (dThdPase) is an angiogenic enzyme and seems to be related to an angiogenesis in human colorectal carcinoma. The incidence of dThdPase-positive cells was significantly correlated with microvessel count in 21 human colorectal carcinomas. Interleukin 1 alpha (IL-1 alpha), tumor necrosis factor alpha (TNF-alpha), interferon alpha (IFN-alpha) interferon gamma (IFN-gamma) induce dThdPase activity in human cancer cell lines. To study whether this phenomenon occurs in the human colorectal carcinomas, we examined the correlation between dThdPase activity and the expression levels of IL-1 alpha, TNF-alpha, IFN-alpha and IFN-gamma in colorectal carcinoma tissues. dThdPase activity was assayed by the methods of Friedkin and Robert, and the expression level of IL-1 alpha, TNF-alpha, IFN-alpha and IFN-gamma was determined by ELISA. dThdPase activity was significantly correlated with the amount of IL-1 alpha (n = 19, r = 0.347, P = 0.0001), INF-alpha (n = 18, r = 0.717, P = 0.008), and IFN-gamma (n = 4, r = 0.9777, P = 0.0234) in human colorectal carcinomas. However, the dThdPase activity was not correlated with the amount of TNF-alpha (n = 21, r = 0.235, P = 0.2682). These results suggested that the expression levels of IL-1 alpha, IFN-alpha and IFN-gamma are correlated with dThdPase activity in human colorectal carcinomas and that these cytokines may cause angiogenesis by inducing the expression of dThdPase.

Carcinoma↗

Contrasting effect of interleukin-13 on interleukin-1 receptor antagonist and proinflammatory cytokine production by human alveolar macrophages.

We investigated the effect of interleukin-13 (IL-13) on production of IL-1 receptor antagonist (IL-1ra) and proinflammatory cytokines by human alveolar macrophages (AM). AM were obtained by bronchoalveolar lavage from healthy donors. The production of IL-1ra and proinflammatory cytokines, such as IL-1 beta, IL-6, and tumor necrosis factor-alpha (TNF-alpha), were quantitated by enzyme immunoassays. AM spontaneously produced IL-1ra, and this production was significantly augmented by IL-13. On the other hand, IL-13 alone did not affect production of proinflammatory cytokines by freshly isolated AM. Upon stimulation with lipopolysaccharide (LPS), AM produced a significantly amount of proinflammatory cytokines as well as IL-1ra, but this production was suppressed by IL-13 in a dose-dependent manner. In contrast, IL-13 caused a small but reproducible increase in LPS-induced IL-1ra production. These regulatory effects of IL-13 were also observed in blood monocytes and macrophages generated in vitro by maturation of blood monocytes with granulocyte/macrophage colony-stimulating factor. These observations suggest that IL-13 may act as an anti-inflammatory cytokine through regulation of cytokine production by AM in the lung.

Adult↗

Serum autoantibody against interleukin-1 alpha is unrelated to the etiology or activity of liver disease but can be raised by interferon treatment.

OBJECTIVE: To clarify the clinical significance of serum levels of interleukin-1 alpha autoantibody in liver disease and their change during interferon therapy for chronic hepatitis. METHODS: By radioimmunoassay, we studied the incidence of serum interleukin-1 alpha autoantibody in 838 healthy controls and 180 patients with liver disease and monitored the change in antibody titer during the interferon therapy for chronic hepatitis. RESULTS: We detected the interleukin-1 alpha autoantibody in 12.6% (106/838) of healthy controls. In patients with liver disease, we found the antibody in 15.6% (5/32) in patients with acute hepatitis, 16.3% (13/80) in patients with chronic hepatitis, 18.8% (9/48) in patients with liver cirrhosis, and 15% (3/20) in patients with autoimmune liver disease. The incidence was not related to either etiology or inflammatory activity of liver disease. Two of three chronic hepatitis patients with initially high serum levels of the antibody (> 2000 ng/ml) showed transient increase in antibody titers during interferon therapy. CONCLUSION: The serum level of interleukin-1 alpha autoantibody was unrelated to the etiology or activity of liver disease. Interferon therapy can cause transient elevation of serum interleukin-1 alpha autoantibody levels.

Adult↗

Cytokine-mediated antitumor effect of bacillus Calmette-Guérin on tumor cells in vitro.

Intravesical instillation therapy of bacillus Calmette-Guérin (BCG) is a useful modality for recurrent superficial transitional-cell carcinoma (TCC) of the urinary bladder. The mechanism of BCG effect has not yet been well characterized. BCG was tested in vitro for cytokine-mediated antiproliferative activity against T24 and KK47 cells (cell lines established from human TCC of the urinary bladder), and ACHN cells (cell line established from human renal cell carcinoma) using a modified human tumor clonogenic assay. Continuous exposure of cells to BCG at concentrations of more than 5 micrograms/ml in the presence of peripheral blood mononuclear cells (PBMC) consisting of a mixture of 5 x 10(4) monocytes/dish and 5 x 10(5) lymphocytes/dish, obtained from healthy donors, significantly inhibited colony formation of T24 and ACHN cells in comparison with growth inhibition in the absence of PBMC (P < 0.05). Slightly inhibited colony formation was observed with KK47 cells under the same conditions. At the same time various cytokines were measured in supernatants when BCG and the same conditioned PBMC were co-cultured. Tumor necrosis factor alpha (TNF alpha) and interleukin-1 beta (IL-1 beta) were detected at markedly high levels at 24 h, and interferon gamma (IFN gamma) was detected at 120 h. IL-2 and macrophage-colony-stimulating factor were not detected. Neutralizing anti-TNF alpha monoclonal antibody significantly reduced the anti-proliferative activity of ACHN cells, and anti-IFN gamma antibody reduced that of T24 cells. The results obtained suggest that cytokines mediated by BCG play an important role in the antitumor activity of BCG and that the sensitivity of bladder cancer cells to the cytokines induced by BCG may differ considerably.

Antibodies, Monoclonal↗

Serum levels of macrophage colony stimulating factor (M-CSF) in liver disease.

We investigated the serum level of macrophage colony stimulating factor in acute and chronic liver disease. Levels of macrophage colony stimulating factor (mean +/- SD, ng/ml) were significantly higher in acute hepatitis (5.67 +/- 1.01, p < 0.01) and chronic active hepatitis (3.34 +/- 1.19, p < 0.01) than in healthy volunteers (1.90 +/- 0.25), asymptomatic hepatitis B virus carriers (1.98 +/- 0.40), and chronic persistent hepatitis (2.34 +/- 0.43). Levels of macrophage colony stimulating factor showed a highly significant correlation with the serum alanine aminotransferase levels in acute hepatitis (p < 0.01, rs = 0.903) and in chronic active hepatis (p < 0.01, rs = 0.672). Levels of macrophage colony stimulating factor in patients with cirrhosis (cirrhosis; 3.11 +/- 0.93 and hepatocellular carcinoma; 3.30 +/- 0.74) were significantly higher than in patients with chronic persistent hepatitis although the alanine aminotransferase levels were not significantly different. In cirrhosis, levels of macrophage colony stimulating factor correlated positively with the serum alanine aminotransferase levels (p < 0.05), total bilirubin levels (p < 0.05), and indocyanine green clearance (p < 0.05). An immunohistochemical study showed an increased number of macrophage colony stimulating factor positive mononuclear cells in portal areas in acute hepatitis. Our findings suggest that; (a) the serum levels of macrophage colony stimulating factor represent ongoing hepatocellular necrosis in acute and chronic liver disease, (b) the source of the increase in the serum macrophage colony stimulating factor levels in hepatic inflammation may be, in part, its production by infiltrating mononuclear cells in the liver, and (c) cirrhosis also causes elevated serum levels of macrophage colony stimulating factor.

Acute Disease↗

Effect of interleukin 1 receptor antagonist on the blood-aqueous barrier after intraocular lens implantation.

Interleukin 1 (IL-1) possesses as an intercellular signal a wide spectrum of inflammatory, metabolic, haematopoetic, immunological, and reparative properties and can be a mediator not only of host defence but also of disease. Reduction of IL-1 can decrease the inflammatory host response. A human recombinant IL-1 receptor antagonist (IL-1ra) was used to block IL-1 after intraocular lens implantation in rabbits. Seventeen rabbits underwent intercapsular phacoemulsification and posterior chamber lens implantation. A 100 micrograms dose (0.1 ml) of IL-1ra (1 mg/ml) was injected into the anterior chamber at the end of surgery in seven rabbits. The 10 rabbits serving as the controls received no IL-1ra. Postoperatively, all rabbits were observed with a slit-lamp, and the aqueous flare intensity was measured with a laser flare cell meter at 12 hours, 1, 2, 3, and 4 days and thereafter at 1, 2, 3, and 4 weeks. Aqueous flare intensity was significantly lower on days 2 and 3, and fibrin deposition much less marked in the eyes treated with IL-1ra, compared with the controls. The results suggest that IL-1 is involved in the postoperative inflammation that occurs after intraocular lens implantation and the use of the IL-1ra would be valuable for reducing this problem.

Animals↗

Effect of IL-1 receptor antagonist and antiserum to TNF-alpha on LPS-induced plasma ACTH and corticosterone rise in rats.

Using an antiserum against tumor necrosis factor (TNF)-alpha and an interleukin (IL-1) receptor antagonist, we studied putative roles of these cytokines in mediating the endotoxin-induced elevation of plasma adrenocorticotropic hormone (ACTH) and corticosterone levels in freely moving rats. Intravenous administration of Escherichia coli lipopolysaccharide (LPS) increased plasma ACTH and corticosterone levels in a dose-dependent manner. The plasma corticosterone reached to its highest level among a series of experiments after the administration of even the smallest dose (0.03 microgram/kg) tested. Plasma ACTH and corticosterone levels in these rats were completely inhibited by the intravenous administration of anti-murine TNF-alpha-rabbit antiserum (anti-TNFAS) after the administration of LPS but not by the intravenous administration of IL-1 receptor antagonist (IL-1RA). On the other hand, both recombinant human IL-1RA and anti-TNFAS significantly inhibited plasma ACTH increase stimulated with 10 micrograms/kg LPS. These findings indicate that 1) when the plasma corticosterone increase induced by intravenous LPS remains below its maximum, the effect is exclusively mediated by TNF-alpha, and 2) when a larger amount of LPS is administered, both IL-1 beta and TNF-alpha participate at least in part in the hypothalamic-pituitary-adrenal axis activation.

Adrenocorticotropic Hormone↗

Increased plasma M-CSF concentration in patients with adult T cell leukemia: clinical correlation.

Plasma concentration of M-CSF was measured in 35 patients with adult T cell leukemia (ATL), using a radioimmunoassay (RIA). ATL patients showed elevated levels of plasma M-CSF concentration when compared with healthy adult volunteers. Higher M-CSF levels were observed in acute ATL patients than in patients with chronic or smouldering ATL (P < 0.0001). There was a significant positive correlation of M-CSF concentration with serum lactic dehydrogenase (LDL) level, a reliable marker for assessing the grade of malignancy in ATL (P = 0.0003). There was, however, no correlation of M-CSF concentration with total counts of peripheral blood ATL cells, neutrophils or monocytes, or with serum calcium levels. Although there was a significant positive correlation of M-CSF concentration with body temperature (P = 0.003), there was not a significant correlation of M-CSF concentration with C-reactive protein (CRP), a protein indicative of the severity of inflammation (P = 0.063). These results indicate that plasma M-CSF concentration reflects the disease activity of ATL, and can thus serve as a marker in the clinical subclassification of ATL patients.

Adult↗

Detection of immunoglobulin binding factor by enzyme-linked immunosorbent assay using two monoclonal antibodies.

Immunoglobulin binding factor (IgBF) found in human seminal plasma may be involved in suppressing antibody production against sperm in the female and male genital tracts. In the present study an enzyme-linked immunosorbent assay (ELISA) for IgBF was developed using monoclonal anti-IgBF antibodies. The sensitivity of the method was 20 pg/ml. The method was used to quantify IgBF in sera from women. In addition high levels of IgBF was found in cervical mucus of the uterus and in bronchial washings. The present results suggest that IgBF is found in tissues that are exposed to the external environment and may be a component of the local immunity system.

Adult↗

[Development of immunoassay for cytokines and its clinical significance].

As measurement systems of cytokines have recently been developed, there are many reports indicating the relationship between cytokines and various diseases. We have also developed various new measurement systems using gene technology and hybridoma technology. The measurement system is composed of the following 5 steps. (1) Cloning of cytokines, (2) Expression of cytokines, (3) Purification of cytokines, (4) Preparation of antibodies (monoclonal and polyclonal antibodies), (5) Development of immunoassay. Cytokines are measured not only in the cytokine itself but also in the receptor, receptor antagonist, and autoantibody. We established the measurement system of cytokines using ELISA (antibody is labeled by enzyme.) for the cytokine itself and RIA (antigen is labeled by isotope.) for the autoantibody to cytokines. The blood concentration of cytokines is low because cytokines are utilized immediately after production and excreted into the urine. Therefore, the immunological responses of individuals can be determined by an ex vivo measurement of the production of cytokines by stimulation of whole blood with LPS not by simply measuring the cytokine itself in plasma. We call this method "Whole Blood Induction Method". This method is positioned as one of the methods which shows the immunological response of cytokines to the outer body at the time of infection using a low volume of human blood. Finally, studies of cytokines have been carried out not only in immunological systems but also in hormone systems which are closely related to cytokines. Studies have also expanded to fields which, to date, have not been thought to be related by investigating adherence factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Direct and indirect effects of human interferon alpha on renal cell carcinoma: a new in vitro assay system for evaluating cytokine-mediated antitumor effects.

A highly purified natural alpha-interferon (nIFN alpha) was tested in vitro for direct and indirect antiproliferative activity against renal cell carcinoma (RCC), using a modified human tumor clonogenic assay and clinically achievable concentrations. In preclinical experiments, the indirect (cytokine-mediated) antiproliferative activity of nIFN alpha was investigated using ACHN cells (established human RCC cell line). Continuous exposure to nIFN alpha at concentrations of more than 5 IU/ml in the presence of feeder cells (a mixture of 5 x 10(4) monocytes/dish and 5 x 10(5) lymphocytes/dish, obtained from healthy donors) significantly inhibited colony formation of ACHN cells in comparison with growth inhibition in the absence of feeder cells (P < 0.05). Various cytokines were measured in the supernatants lying over the medium on the feeder-layer agarose containing the same conditioned feeder cells. With IFN alpha at 500 IU/ml, tumor necrosis factor alpha (TNF alpha) and IFN gamma were detected at markedly high levels for 2-24 h. Neutralizing anti-TNF alpha monoclonal antibody significantly reduced the indirect antiproliferative activity. Using our modified human tumor clonogenic assay technique, sufficient numbers of colonies for drug testing were observed in 19 of 31 surgical specimens (61.3%). In these clinical materials, nIFN alpha at a clinically achievable concentration (50 IU/ml) significantly inhibited colony growth in the presence of feeder cells consisting of 5 x 10(4) monocytes/dish and 5 x 10(5) lymphocytes/dish, obtained from the patient whose tumor was examined (P < 0.05). In colony-forming cases, a significant correlation between the percentage colony survival and TNF alpha concentration in the supernatant was observed (r = -0.95, P < 0.01). These results suggest that this assay system may be an appropriate technique for evaluating the antiproliferative activities of nIFN alpha involving cytokine-mediated action, and that TNF alpha may play an important role in this cytokine-mediated activity.

Carcinoma, Renal Cell↗

The structure of recombinant human carboxy-terminal-truncated macrophage colony-stimulating factor derived from mammalian cells.

The structure of recombinant human carboxy-terminal-truncated macrophage colony-stimulating factor expressed in CHO cells was investigated. The bioactive protein ([-32-153]M-CSF), expressed from a nucleotide sequence that encoded a signal peptide of 32 amino acids and N-terminal amino acids numbers 1-153, was heterogeneous in terms of molecular mass, as analyzed by SDS-PAGE, because of the presence of N-linked sugar moieties. The primary structure of the polypeptide was determined by sequence analysis and amino acid analysis of the fragments obtained from lysylendopeptidase digests of reduced and alkylated M-CSF, and from pepsin digests of the intact molecule. A sugar chain was located only at Asn-122 of the two putative sites of N-glycosylation that were present per subunit. The homodimeric structure appeared to have seven disulfide bonds, formed by inter- or intra-molecular linkages, since there were no free thiol groups in the molecule. The assignment of disulfide bonds by sequence analysis using peptide fragments indicated the combinations of Cys7-Cys90, Cys48-Cys139, and Cys102-Cys146. Gel-filtration analysis of Ser31[-32-153]M-CSF, in which the remaining Cys31 was replaced by Ser and which was expressed in COS cells, suggested that the mutein existed as a monomer. Our study shows that the disulfide-bond pairings of [-32-153]M-CSF that is expressed and post-translationally modified in mammalian cells are identical to those of Escherichia coli-derived [3-153]M-CSF with only one intermolecular disulfide bond, namely, Cys31-Cys31.

Alkylation↗

Predominant production of amniotic interleukin-1 alpha in cases with premature rupture of the membranes.

PROBLEM: The physiological significances of the two known subtypes of interleukin-1 (IL-1) in amniotic fluid (AF) were examined by measurements of their concentrations and detection of their location. METHOD: Each IL-1 subtype in AF collected from 61 patients were examined by newly developed enzyme-linked immunosorbent assay with high sensitivity. Placenta and umbilical cord from 17 patients were examined immunohistochemically for localization of IL-1. RESULTS: Different types of IL-1 were predominant in AF; the mean (+/- SE) concentration of IL-1 beta (412.8 +/- 105.4 pg/ml) was significantly higher (P < 0.01) than that of IL-1 alpha (116.4 +/- 26.7 pg/ml) in cases with spontaneous vaginal delivery, whereas the concentration of IL-1 alpha (243.1 +/- 81.4 pg/ml) was significantly higher (P < 0.01) than that of IL-1 beta (139.7 +/- 59.4 pg/ml) in cases with premature rupture of the membranes (PROM) without intrauterine infection. In these cases, immunohistochemical studies revealed the presence of IL-1 alpha in the trophoblastic layer of the placenta and epithelium of the umbilical cord. CONCLUSION: Amniotic IL-1 alpha was detected predominantly in cases with PROM, and it is thought to be produced in placenta and fetal skin keratinocyte.

Adult↗

Establishment of radioimmunoassay for human macrophage colony-stimulating factor using recombinant human macrophage colony-stimulating factor as tracer and immunogen.

A sensitive and reliable radioimmunoassay (RIA) for human macrophage colony-stimulating factor (M-CSF) was developed using recombinant human M-CSF (rhM-CSF) as tracer and immunogen. The assay was quantitative over the range of 50 pg/ml and 5.0 ng/ml for M-CSF in human urine and serum, and more sensitive and specific than the murine bone marrow assay. The average level of human M-CSF in urine from normal males (N = 71) and females (N = 46) was 3.94 +/- 1.78 ng/ml (2.85 +/- 1.15 micrograms/g creatinine), and 3.53 +/- 1.70 ng/ml (3.31 +/- 1.12 micrograms/g creatinine), respectively. The serum levels were 1.95 +/- 0.38 ng/ml for males (N = 117), and 1.93 +/- 0.49 ng/ml for females, (N = 16). The results with the urine and sera showed that there was no difference in the M-CSF levels due to age or gender.

Blotting, Western↗