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Biomedical subjects

Y Fukutomi

Publications and source records attributed to Y Fukutomi.

At least 19 recordsLinked to original sources

Polymorphism of the 5' flanking region of the IL-12 receptor beta2 gene partially determines the clinical types of leprosy through impaired transcriptional activity.

BACKGROUND: Individual differences in T cell responsiveness to interleukin 12 (IL-12), resulting from inherited factors, may be responsible for differences in the intensity of cell mediated immune (CMI) responses in patients with leprosy, a disease with a wide clinical spectrum. AIM: Polymorphisms in the 5' flanking region of the IL12RB2 gene were analysed to determine potential immunogenetic factors affecting CMI responses, using leprosy as a model. METHODS: Polymorphisms in the 5' flanking region of IL12RB2 were examined using direct sequencing techniques, and allele frequencies between patients with lepromatous leprosy and patients with tuberculoid leprosy were compared. The effect of these single nucleotide polymorphisms (SNPs) on IL12RB2 expression was estimated using the dual luciferase reporter gene assay in Jurkat T cells. RESULTS: Several SNPs, including -1035A>G, -1023A>G, -650delG, and -465A>G, were detected within the 5' flanking region of IL12RB2. The frequency of haplotype 1 (-1035A, -1023A, -650G, -464A) was high in the general Japanese population, but was significantly lower in lepromatous patients compared with tuberculoid patients and healthy controls. Reporter gene assays using Jurkat T cells revealed that all haplotypes carrying one or more SNP exhibited a lower transcriptional activity compared with haplotype 1. CONCLUSION: SNPs within the 5' flanking region of IL12RB2 affect the degree of expression of this gene and may be implicated in individual differences in CMI responsiveness to mycobacterial antigens, leading to lepromatous or tuberculoid leprosy.

5' Flanking Region↗

Type II citrullinemia in an elderly patient treated with living related partial liver transplantation.

A 60-year-old woman was admitted to our hospital for repeated consciousness disturbance. Blood examination showed hyperammonemia, and plasma amino acid analysis revealed a marked increase in the citrulline level. To establish a diagnosis, a percutaneous needle biopsy of the liver was performed. The determination of the urea cycle enzyme activities revealed a selective marked decrease in argininosuccinate synthetase activity, indicating the final diagnosis of type II citrullinemia. The mean survival period of this disease after the appearance of symptoms has been reported as 26.4 months, and most conservative treatments are not effective. We performed a living related partial liver transplantation. Over the subsequent 13-month follow-up, the patient's condition has remained fairly good.

Biopsy, Needle↗

[Clinical evaluation in oral lichen planus with chronic hepatitis C: the role of interferon treatment].

Hepatitis C virus (HCV) infection induces a variety of extrahepatic manifestations such as oral lichen planus (OLP). To clarify the role of HCV in the development of OLP, we investigated the occurrence of OLP in patients with chronic hepatitis C treated with interferon (IFN). Of 275 patients with chronic hepatitis C, 6 developed OLP during the IFN treatment. However, OLP developed in none of 230 patients with chronic hepatitis C who did not undergo the IFN therapy. The IFN treatment in chronic hepatitis C patients developed OLP significantly, as compared with the non-treated group (p < 0.05). 4 of 6 patients who developed OLP during the IFN treatment had a complete response with normalization of ALT levels and undetectable HCV RNA after the treatment. There were no significant correlations between the effect of the IFN treatment and outcome of OLP. Furthermore, 3 of the 6 patients developed OLP, when serum HCV RNA became negative. These results suggest that direct viral factors may not be important in the pathogenesis of OLP in patients with chronic hepatitis C. Immunological changes caused by IFN may play a role in the development of OLP associated with HCV infection.

Adolescent↗

[Multiple myeloma presenting as massive ascites].

Ascites is a rare complication of multiple myeloma. We report a case of multiple myeloma with peritoneal involvement. An 80-year-old woman was admitted to our hospital because of massive ascites. Laboratory findings included an Hb of 7.8 g/dl, IgA of 2,160 mg/dl, and CA125 of 942 IU/ml. Immunoelectropheresis analysis detected a monoclonal component of IgA lambda in serum, and of BJP lambda in urine. Bone marrow aspirtion revealed normal cellularity with 32.7% atypical plasma cells. The ascites was characterized by an exudate with numerous atypical plasma cells and elevated IgA and CA125 levels. The IL-6 level was 22 pg/ml and 79 pg/ml in serum and ascites, respectively. A diagnosis of IgA lambda multiple myeloma with peritoneal involvement was made. Chemotherapy consisting of melphalan and prednisolone reduced the serum IgA and CA125 levels markedly, and alleviated the patient's ascites.

Aged↗

[Non-Hodgkin's lymphoma with Toxoplasma encephalitis].

A 62-year-old man was admitted to our hospital due to fever and systemic lymph-node swelling on June 9, 1998. He was given a diagnosis of non-Hodgkin's lymphoma (diffuse mixed T cell lymphoma) with involvement of mediastinum and para-aortic lymph nodes, pleura, peritoneum, and bone marrow. After diagnosis, combined chemotherapy (CHOP regimen) was started. On day 11, the patient's consciusness level suddenly deteriorated. A brain computed tomographic scan showed no abnormal findings. A cytospin smear of cerebrospinal fluid disclosed tachyzoides (Toxoplasmic bodies), thus yielding a diagnosis of Toxoplasma encephalitis. Oral sulfadoxine pyrimethamine rapidly alleviated the patient's consciousness disturbance. One month later, a cytospin smear and RT-PCR analysis of cerebrospinal fluid detected no tachyzoides. Complete remission of lymphoma was achieved after 2 courses of CHOP therapy. Toxoplasma encephalitis should be considered a potential cause of consciousness disturbance in immunocompromised hosts, such as patients with malignant lymphoma. Cytospin smears of cerebrospinal fluid are a useful tool for the early diagnosis of Toxoplasma encephalitis.

Animals↗

Antiproliferative effect of carotenoids on human colon cancer cells without conversion to retinoic acid.

The present study employed two human colon cancer cell lines, DLD-1 and Colo 320DM, to investigate whether the provitamin A activity of carotenoids is necessary for their antitumor effect on colon cancer. Carotenoids, including alpha- and beta-carotene and canthaxanthin, significantly suppressed cell viability [measured by tetrazolium (MTT) assay], DNA synthesis (measured by [3H]thymidine uptake), and cell proliferation (measured by cell counting) and thus showed growth-inhibitory effects on both cancer cell lines. Because canthaxanthin does not have provitamin A activity, these results suggest that the carotenoid directly inhibited the cell growth. Moreover, the effective dose of retinoic acid, an active metabolite of vitamin A, was much higher than that of alpha- or beta-carotene. A retinoic acid-inducible gene, retinoic acid receptor-beta, was not enhanced in either type of cancer cell by treatment with alpha- or beta-carotene. Therefore, like canthaxanthin, alpha- and beta-carotene might also exert their tumor-suppressing effects without being converted to retinoids. These results suggest that a certain antitumor activity of carotenoids may not necessarily require their provitamin A activity.

Carotenoids↗

Dharmendra antigen but not integral M. leprae is an efficient inducer of immunostimulant cytokine production by human monocytes, and M. leprae lipids inhibit the cytokine production.

Killed integral Mycobacterium leprae, Mitsuda antigen, and chloroform-treated M. leprae, Dharmendra antigen (Dh-Ag), have been used for the classification of leprosy patients based on cell-mediated immunity. Heat-killed M. leprae also were used as a component of the Convit vaccine. Human blood monocytes were stimulated with M. leprae or Dh-Ag and their cytokine-inducing ability was compared. Monocytes were cultured in the presence of fresh human serum because of the efficiency of cytokine induction and the phagocytosis of M. leprae have been shown to be optimal in the presence of fresh serum. M. leprae and Dh-Ag were equally phagocytosed by monocytes. Dh-Ag was more potent than M. leprae in the induction of immunostimulatory/proinflammatory cytokines, interleukin-1 (IL-1), IL-6 and tumor necrosis factor (TNF). In contrast, a comparable level of IL-1ra, an immunosuppressive cytokine, was induced by M. leprae and Dh-Ag. The lipids extracted from M. leprae induced none of these cytokines by monocytes. Nevertheless, when monocytes were pretreated with the lipids followed by stimulation with Dh-Ag, productions of IL-1, IL-6 and TNF were all inhibited in a dose-dependent manner. However, the lipids did not inhibit the cytokine production induced by other stimuli including BCG and lipopolysaccharide. Moreover the lipids did not affect the production of IL-1ra. These results suggest that the lipids from M. leprae are responsible for the poor cytokine-inducing ability of M. leprae, thus favoring their infection. These results also suggest that Dh-Ag rather than integral M. leprae may be useful as a vaccine candidate because Dh-Ag is able to induce a large amount of cytokines from monocytes.

Antigens, Bacterial↗

Positive and negative regulations of albumin gene expression by retinoids in human hepatoma cell lines.

All-trans-3,7,11,15-tetramethyl-2,4,6,10,14-hexadecapentaenoic acid (designated "acyclic retinoid") induced upregulation of the albumin gene expression at its transcriptional level, whereas all-trans-retinoic acid (RA) induced downregulation of the expression in both PLC/PRF/5 and HuH7 human hepatoma cell lines. These up- and down regulations of the albumin gene expression coordinated with high and low levels of mRNA for hepatocyte nuclear factor-1 (HNF-1), which is one of the most potent transcription factors for the albumin gene, implying that retinoids may regulate albumin gene expression through HNF-1 expression in opposite ways. The PLC/PRF/5 and HuH7 hepatoma cell lines expressed retinoid X receptor-alpha (RXR alpha) mRNA, whose expression was constitutive. Acyclic retinoid and all-trans-RA both induced upregulation of retinoic acid receptor-beta (RAR beta), and both suppressed cell proliferation-related phenotypic expressions by the alpha-fetoprotein gene and the c-myc oncogene. 9-cis-RA, whose receptor is known to be RXR alpha, also induced upregulation of albumin and HNF-1 expression. These results suggest that acyclic retinoid may act through both RXR alpha and RAR beta, whereas all-trans-RA conveys only RAR beta-mediated functions, at least in these two hepatoma cell lines.

Albumins↗

Inhibitory effects of (-)-epigallocatechin gallate on spontaneous hepatoma in C3H/HeNCrj mice and human hepatoma-derived PLC/PRF/5 cells.

The inhibitory effect of (-)-epigallocatechin gallate (EGCG), a main constituent of Japanese green tea, on spontaneous hepatoma in C3H/HeNCrj mice was investigated. A total of 72 mice were divided into three groups; the control group without EGCG, and two experimental groups receiving 0.05% (w/w) or 0.1% EGCG in drinking water. EGCG reduced the incidence of hepatoma-bearing mice from 83.3% (control) to 56.0% (0.05% EGCG) and 52.2% (0.1% EGCG), and also reduced the average number of hepatomas per mouse from 1.83 (control) to 0.72 (0.05% EGCG) and 0.91 (0.1% EGCG) at week 65. Ridit analysis of the distribution of the number of hepatomas in each group revealed that EGCG significantly increased the rate of mice without hepatoma in the two EGCG groups as compared to the control. EGCG did not affect body weight gain, food consumption or any serum biochemical parameter. EGCG inhibited the growth and secretion of alpha-fetoprotein by human hepatoma-derived PLC/PRF/5 cells without decreasing their viability. These results indicate that EGCG may be a practical, nontoxic preventive agent against human hepatoma.

Animals↗

Down regulation of Ia expression in macrophages following incubation with mycobacteria.

Macrophages are known to release cytokines in response to various kinds of stimulators. In the present study, peritoneal macrophages from C3H/He or C3H/HeJ mice were incubated in vitro with heat-killed M. lepraemurium, M. intracellulare or M. gordonare for 3 days followed by harvest culture supernatant to analyze cytokine activities. It, therefore, seems that macrophages phagocytizing these mycobacteria, released interleukin-1 (IL-1) and tumor necrosis factor (TNF) in culture media. The amount of release was dose dependent on mycobacteria employed. In addition, macrophages, as already have reported elsewhere, treated with IFN for 2 to 3 days showed enhanced expression of surface Ia; although the expression was inhibited if the cells phagocytized mycobacteria. Similarly, the reduced expression of Ia was observed in peritoneal macrophages from MRL/lpr mice after 3 day-culture with mycobacteria in vitro. More importantly, in the presence of the supernatant obtained from macrophages incubated with mycobacteria, IFN gamma-treated normal macrophages exhibited suppressed expression of Ia. These results demonstrate that cytokine release and reduced expression of surface Ia in macrophages are simultaneous phenomena after phagocytosis of mycobacteria. Suppression of Ia may be in part induced by Ia suppressive factor(s) released from mycobacterium-phagocytized macrophages.

Animals↗

Clofazimine-mediated augmentation of LPS-induced tumor necrosis factor production in macrophages.

Tumor necrosis factor (TNF) exerts multiple biological activities including immune response. It is also believed to play an important role in anti-bacterial response. In this study in vitro, we observed augmentation of LPS-induced TNF production from mouse macrophages by clofazimine treatment. Rifampicin, however, did not indicate such an activity. Clofazimine itself, on the other hand, did not have any TNF-inducing activity. Clofazimine is a well known anti-leprosy drug; in addition, from the results obtained here, this drug could induce anti-M. leprae response of host by way of the augmented immune response by enhanced cytokine production from macrophages.

Animals↗

Treatment of acute experimental toxoplasmosis with investigational poloxamers.

Because of the limited chemotherapeutic approaches available to treat reactivated latent Toxoplasma gondii infection manifested as toxoplasmic encephalitis in AIDS patients, investigation of novel chemotherapeutic agents is warranted. Several poloxamers (nonionic block copolymers composed of a central hydrophobic chain of polyoxypropylene flanked by two hydrophilic chains of polyoxyethylene) were tested for their abilities to alter the course of acute infection with a highly virulent T. gondii in mice. The effect varied markedly with the length of the constituent chains of the copolymers. The most effective preparations were highly effective when administered after infection and afforded remarkable protection against 10 to 1,000 100% lethal doses of T. gondii. Protection was dose dependent, and multiple treatments were more effective than single treatment. These preliminary findings warrant additional studies to determine whether this novel form of antitoxoplasma chemotherapy may prove promising in the treatment or prevention of acute toxoplasmic encephalitis in humans.

Acute Disease↗

Regulation of murine macrophage effector functions by lipoarabinomannan from mycobacterial strains with different degrees of virulence.

Lipoarabinomannan (LAM) is the major arabinose- and mannose-containing phosphorylated lipopolysaccharide (LPS) in mycobacterial cell walls. LAM preparations from a virulent strain (Erdman) (LAM(Erdman)) and an attenuated strain (H37Ra) (LAMH37Ra) of Mycobacterium tuberculosis, as well as from M. leprae (a virulent mycobacterium), were analyzed for their effects on various macrophage (M phi) effector functions. LAMH37Ra, like gram-negative LPS, exhibited a dose-dependent ability to induce tumor necrosis factor alpha (TNF-alpha) production in normal M phi, and gamma interferon (IFN-gamma) priming of the M phi greatly augmented the levels of TNF-alpha. However, the effects of LAMH37Ra were unaffected by polymyxin B, which totally abrogated the effects of LPS. LAM(Erdman) and LAM from M. leprae, on the other hand, induced virtually no TNF-alpha production. Analysis of M phi mRNA by reverse transcription-polymerase chain reaction revealed that the levels of production. Analysis of M phi mRNA by reverse transcription-polymerase chain reaction revealed that the levels of TNF-alpha mRNA induced by the various preparations correlated with the levels of TNF-alpha protein detected. Interestingly, both LAMH37Ra and LAM(Erdman) could block subsequent IFN-gamma- and LPS-induced M phi activation, a previously reported measure of the potent ability of LAM to down-regulate M phi effector functions. Two lines of evidence suggested, however, that M phi cyclooxygenase products did not play a role in this down-regulation. LAMH37Ra and LPS could induce the production of NO2- in both normal and IFN-gamma-primed M phi, whereas LAM(Erdman) could stimulate NO2- production only in primed M phi. Both LAMH37Ra and LAM(Erdman) could substitute for LPS as a triggering signal for IFN-gamma-primed M phi in a toxoplasma killing assay. The triggering ability of LAM(Erdman), however, was abrogated by an anti-TNF-alpha antibody, suggesting that sufficient TNF-alpha production was stimulated by LAM(Erdman) to drive a M phi function relevant in host resistance. Thus, mycobacterial LAM is a potent regulator of M phi functions, a fact that may have important consequences in mycobacterial disease.

Animals↗

Differential production of interleukin 1 (IL-1), IL-6, tumor necrosis factor, and IL-1 receptor antagonist by human monocytes stimulated with Mycobacterium leprae and M. bovis BCG.

Human blood monocytes cultured in various serum conditions were stimulated with Mycobacterium leprae or M. bovis BCG and their cytokine-inducing abilities were compared. BCG, either live or killed, induced production of interleukin 1 (IL-1), IL-6, tumor necrosis factor (TNF), and IL-1 receptor antagonist (IL-1ra). Live BCG at a lower bacterial number was more potent than killed BCG in the induction of IL-6 and TNF. In contrast to BCG, killed M. leprae induced few cytokines except for IL-1ra. Similar results were obtained when monocytes were cultured in the presence of untreated or heat-inactivated fetal bovine serum (FBS). When FBS and human serum (HS) were compared and the effect of heat inactivation was investigated, monocytes in HS produced the most cytokines, then those in FBS, irrespective of heat inactivation, and those in heat-inactivated HS produced the least cytokines. There were no differences between live and killed M. leprae, and BCG were far more potent than M. leprae in all of our experimental conditions, indicating that the poor cytokine (IL-1, IL-6 and TNF)-inducing ability of M. leprae was not due to their viability. Cytokine production was partially in parallel with the phagocytosis of the mycobacteria. These results suggest that M. leprae favor their infection by evoking little host reaction through the induction of only low levels of immunostimulatory or proinflammatory cytokines but a substantial amount of immunosuppressive cytokine.

Animals↗