Serum proinflammatory cytokines and adhesion molecules in ulcerative colitis

BACKGROUND/AIMS: The aim of this study was to define the correlation between serum markers, such as proinflammatory cytokines and adhesion molecules, and disease activity in ulcerative colitis (UC). METHODOLOGY: Nineteen patients with UC treated in our hospital from April 2003 to June 2004, were enrolled into this study. We measured serum interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-alpha), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule (VCAM-1) from a blood sample. We investigated the correlation between these cytokine molecules and clinical activity. RESULTS: Serum levels of IL-6 after treatment were significantly decreased proportionately as disease activity improved. Serum levels of IL-8 also significantly correlated with disease activity. On the other hand, serum levels of TNF-alpha were within the normal range in most of cases despite being in the active phase. There were also no significant differences between before and after treatment in serum levels of ICAM-1 or VCAM-1. CONCLUSIONS: Serum IL-6 and IL-8 significantly reflected disease activity in patients with UC.     

Rapid induction of OX40 ligand on primary T cells activated under DNA-damaging conditions

We have previously demonstrated that normal human T cells either long-term repeatedly stimulated or freshly activated in vitro in the presence of TGF-beta express the cell surface T-cell costimulating molecule OX40 ligand (OX40L). To further elucidate the kinetics of OX40L expression by human T cells, we have examined whether cell proliferation was required for the expression of OX40L. Thus, normal fresh peripheral blood mononuclear cells were stimulated with immobilized anti-CD3 antibody in the presence of the DNA synthesis-blocking agents such as mitomycin C, 5-fluorouracil, or X-ray irradiation. Flow cytometric analyses demonstrated that a significant frequency of these DNA-damaged activated primary CD4(+) and CD8(+) T cells became OX40L(+) as early as 1 hour after treatment. The OX40L induction on the DNA-damaged activated T cells was inhibited by treatment with either RNA or protein synthesis inhibitors, actinomycin D, or cycloheximide, respectively. Induced OX40L on T cells was functional because it bound recombinant OX40. These data indicate that human primary T cells are programmed to rapidly express functional OX40L molecules after stimulation under DNA-damaging conditions, demonstrating that the induction of OX40L by T cells is independent of cell proliferation. The clinical implications of these new findings are discussed.     

A sleep disordered breathing as the lifestyle-related diseases

Lifestyle related disease is a generic term for diseases such as cardiovascular diseases, diabetes mellitus and cancer caused by life style or life habit, and one of its fundamental causes is obesity. The reason why most people put on weight after their middle age is mainly because of the increase of visceral fat by the decrease in basal metabolism and the amount of momentum despite of unchanging appetite. Due to this sequence of weight gain, after middle age upper respiratory tract becomes narrower, and it worsens obstructive sleep apnea syndrome (OSAS). Since mastication is to provoke and maintain arousal, OSAS patients, who especially feel strong sleepiness, tend to encourage them to be obesity by frequent mastication that leads them to the tendency to overeat. Two main symptoms of OSAS are snoring and sleepiness; however, the essence of sleepiness is the worse quality of sleep due to apnea. In addition, a vicious circle is eventually generated because sleep deprivation and sleep disorders affects hypertension and glucose intolerance, and those worsen lifestyle disease. In order to break this off, it is necessary to review life style and habit, and improve not only on diet and exercise therapy but also on sleep.     

Differences in sensitivity to DNA-damaging Agents between XRCC4- and Artemis-deficient human cells

Non-homologous end-joining (NHEJ) is the predominant pathway for the repair of DNA double-strand breaks (DSBs) in human cells. XRCC4 is indispensable to NHEJ and functions together with DNA ligase IV in the rejoining of broken DNA ends. Artemis is a nuclease required for trimming of some, but not all, types of broken DNA ends prior to rejoining by the DNA ligase IV/XRCC4 complex. To better understand the roles of these factors, we generated XRCC4- and Artemis-deficient cells from the human colon adenocarcinoma cell line HCT116 by gene targeting and examined their cellular responses to several DNA-damaging agents including X-rays. As anticipated, kinetic analyses of γ-H2AX foci and chromosomal aberrations after ionizing radiation (IR) demonstrated a serious incompetence of DSB repair in the XRCC4-deficient cells, and relatively moderate impairment in the Artemis-deficient cells. The XRCC4-deficient cells were highly sensitive to etoposide and 5-fluoro-2'-deoxyuridine as well as IR, and moderately sensitive to camptothecin, methyl methanesulfonate, cisplatin, mitomycin C, aphidicolin and hydroxyurea, compared to the parental HCT116 cells. The Artemis-deficient cells were not as sensitive as the XRCC4-deficient cells, except to cisplatin and mitomycin C. By contrast, the Artemis-deficient cells were significantly more resistant to hydroxyurea than the parental cells. These observations suggest that Artemis also functions in some DNA damage response pathways other than NHEJ in human cells.     

MACROGLOBULINEMIA WALDENSTRUM COMPLICATED BY AUTOIMMUNE HEMOLYTIC ANEMIA, MENINGEAL SIGN AND FEMORAL LYSIS

A necropsied case of macroglobulinemia Waldenström with unusual complications was presented; the patient was found to have autoimmune hemolytic anemia, first. During the course of its treatment, he developed monoclonal immunoglobulin M in serum together with lytic osseous lesion in both femurs, and died of meningeal involvement by tumor cells. Clinically, he had hepatosplenomegaly and generalized lymphadenopathy. The macroglobulin was kappa type of light chain, ultracentrifugation showed a sharp spike of 21S in 18.6%, and myelogram revealed increased lymphocytoid series of 29.6%. It was proved that autoantibody causing autoimmue hemolytic anemia was composed of IgG and macroglobulin itself had no activity as an anti-red cell antibody. An emphasis was made that autoimmune hemolytic anemia followed by macroglobulinemia is based on the state of immunodeficiency of this patient.     

The reconstituted human Chl12-RFC complex functions as a second PCNA loader

The sister chromatid cohesion factor Chl12 shares amino acid sequence similarity with RFC1, the largest subunit of replication factor C (RFC), and forms a clamp loader complex in association with the RFC small subunits RFCs2-5. It has been shown that the human Chl12-RFC complex, reconstituted with a baculovirus expression system, specifically interacts with human proliferating cell nuclear antigen (PCNA). The purified Chl12-RFC complex is structurally indistinguishable from RFC, as shown by electron microscopy, and it exhibits DNA-stimulated ATPase activity that is further enhanced by PCNA, and by DNA binding activity on specific primer/template DNA structures. Furthermore, the complex loads PCNA onto a circular DNA substrate, and stimulates DNA polymerase delta DNA synthesis on a primed M13 single-stranded template in the presence of purified replication proteins. However, it cannot substitute for RFC in promoting simian virus 40 DNA replication in vitro with crude fractions. These results demonstrate that the human Chl12-RFC complex is a second PCNA loader and that its roles in replication are clearly distinguishable from those of RFC.     

TT virus infection in patients with chronic liver disease of unknown etiology

The role of a novel virus, designated as TT virus (TTV), as a cause of chronic liver disease has not been well defined. We investigated the prevalence of TTV among 69 patients with chronic liver disease of unknown etiology and 50 volunteer blood donors with normal transaminase levels. TTV DNA was amplified by polymerase chain reaction (PCR) by using two different sets of primers: one based on the sequence of the original N22 clone within the open reading frame 1 (set A) and the other derived from the untranslated region (set B). The prevalence of TTV detected by PCR primers set A only, set B only, and in total (by either set A or B) was 11 (31%), 31 (86%), and 31 (86%) of 36 patients with chronic hepatitis; 2 (40%), 4 (80%), and 4 (80%) of 5 with cirrhosis; 11 (39%), 17 (61%), and 22 (79%) of 28 with hepatocellular carcinoma; and 9 (18%), 39 (78%), and 40 (80%) of 50 volunteer blood donors, respectively. Of the interpretable 25 PCR products amplified with primers set A, 9 were classified as genotype 1a, 10 as genotype 1b, 4 as genotype 2, 1 as genotype 3, and 1 as genotype 4. Molecular evolutionary analysis did not suggest any particular strains of TTV that might be associated with chronic liver disease. The nucleotide sequences of the untranslated region on which PCR primers set B were designed were highly conserved, and the interpretable 22 PCR products amplified with primers set B were not clearly divisible into distinct genotypes. Our findings provided no evidence that TTV is a causative agent of chronic liver disease.