Aim: Persistent hepatitis B virus (HBV) infection is characterized by a weak CD8(+) T cell response to HBV. Immunotherapeutic strategies that overcome tolerance and boost these suboptimal responses may facilitate viral clearance in chronically infected individuals. Therefore, we examined whether CD25(+)CD4(+) regulatory T (Treg) cells might be involved in a inhibition of CD8(+) T cell priming or in the modulation of the magnitude of the 'peak' antiviral CD8(+) T cell response primed by DNA immunization.
View Article and Find Full Text PDFIn an attempt to establish a thrombotic middle cerebral artery (MCA) occlusion model using cynomolgus monkeys, we measured the blood flow in the main MCA tract and cerebral cortex, brain damage, and neurological deficits, and compared them with those of mechanical MCA occlusion model. Thrombotic occlusion was induced photochemically by green light application on the MCA following rose bengal treatment; mechanical occlusion was induced by MCA clipping for 3h. Patency of the main MCA tract showed two patterns in the thrombotic model: permanent occlusion or cyclical flow reduction (CFR).
View Article and Find Full Text PDFA hot-water extract of adzuki was obtained by boiling beans of adzuki (Vigna angularis). This hot-water extract was fractionated using HP-20 column chromatography. Its distilled water fraction (WEx) was found to stimulate tyrosinase activity in cultured mouse B16 melanoma cells and hair color pigmentation in C3H mice.
View Article and Find Full Text PDFToll-like receptors (TLR) play a key role in innate immunity. To examine the ability of diverse TLRs to modulate hepatitis B virus (HBV) replication, HBV transgenic mice received a single intravenous injection of ligands specific for TLR2, TLR3, TLR4, TLR5, TLR7, and TLR9. All of the ligands except for TLR2 inhibited HBV replication in the liver noncytopathically within 24 h in a alpha/beta interferon-dependent manner.
View Article and Find Full Text PDFEach of the aromatic, acidic and basic amino acid residues in HM-1 were separately substituted with alanine by site-directed mutagenesis. The mutant genes were successfully expressed in HM-1 resistant Saccharomyces cerevisiae. HM-1 gene analogues corresponding to the aromatic substitutions resulted in lower production of HM-1 analogues.
View Article and Find Full Text PDFAn electrochemical DNA chip was constructed for simultaneous genotyping of single nucleotide polymorphisms (SNPs) using genomic DNA extracted from blood samples. This chip consisted of electrodes located on a single piece of substrate and allele-specific oligonucleotide probes on the electrodes. As a first application, the 4 SNPs (MxA[-88], MxA[-123], MBL[X/Y], and MBL[A/B]), which have association with the efficacy of interferon therapy for HCV patient, were genotyped on the new DNA chip.
View Article and Find Full Text PDFThe 40% ethanol eluent of the fraction of hot-water extract from adzuki beans (EtEx.40) adsorbed onto DIAION HP-20 resin has many biological activities, for example, antioxidant, antitumorigenesis, and intestinal alpha-glucosidase suppressing activities. This study examined the inhibitory effect of EtEx.
View Article and Find Full Text PDFJ Nutr Sci Vitaminol (Tokyo)
October 2004
We compared the effects of capsinoid, a non-pungent component, on serum and liver lipids, with that of synthetic capsaicin in hyperlipidemic rats. Male Wistar rats of 9 wk old were divided into 4 groups: a control group receiving a high-fat diet containing 1% cholesterol, and capsaicin, capsinoid-I and capsinoid-II groups supplemented with 0.1 mmol of N-pelargonylvanillylamide (synthetic capsaicin), and 0.
View Article and Find Full Text PDFRECQ4 is a member of the RecQ helicase family, which has been implicated in the regulation of DNA replication, recombination and repair. p53 modulates the functions of RecQ helicases including BLM and WRN. In this study, we demonstrate that p53 can regulate the transcription of RECQ4.
View Article and Find Full Text PDFWe developed a system that uses the single-molecule fluorescence detection system MF10S to assess quantitatively the activity of WRN helicase, the product of the causative gene of Werner syndrome that includes premature ageing. Double-strand DNA substrates labeled with the fluorescence dye TAMRA at the 5' end and with a quencher at the 3' end of the counter strand were incubated with a single trapper oligonucleotide and Werner helicase, and the resultant single DNA fragments labeled with TAMRA produced by the unwinding of WRN helicase were detected using the MF10S. The results using this system and those using polyacrylamide gel electrophoresis were well correlated.
View Article and Find Full Text PDFA hot water extract obtained by boiling adzuki beans (Vigna angularis) to produce bean paste for Japanese cake showed inhibitory activity against alpha-glucosidase, alpha-amylase, maltase, sucrase, and isomaltase after HP-20 column chromatography. The IC(50) values for each hydrolylase were 0.78 mg/ml (alpha-amylase), 2.
View Article and Find Full Text PDFTelomerase-negative immortal human cells maintained telomere length by a mechanism called alternative lengthening of telomeres (ALT mechanism). These cells (ALT cells) have two prominent characteristics of long telomere repeats at each chromosome end revealed by Southern blotting (terminal restriction fragments: TRF) and the presence extrachromosomal telomere repeat (ECTR) DNA. We report here that the TRF length of ALT cells revealed by the conventional unidirectional (UD) current or pulse-field (PF) current electrophoresis appeared to be over estimated.
View Article and Find Full Text PDFTreatment of human stomach cancer KATO III cells with hot-water extracts from adzuki beans led to their growth inhibition as well as apoptosis induction. There are morphological changes in the cultured cells treated with the extracts, by which DNA fragmentation characteristic of apoptosis was actualized both concentration- and time-dependently. In contrast, N-acetyl-L-cysteine suppressed such DNA fragmentation, implying that the extracts from adzuki beans might exert antitumorigenicity via active oxygen-induced apoptosis.
View Article and Find Full Text PDFHuman RecQ helicases, including the Werner syndrome helicase, participate in maintaining the integrity of the genome by suppressing illegitimate recombination or by repair of local DNA structural damage. Deterioration or loss of RecQ helicase associated with aging or genetic disorder results in genomic instability in tissues and organs where certain RecQ helicases are needed to correct aberrant DNA during proliferation. Such genomic instability, if not corrected, causes increased apoptotic cell death that would result in reduction of cell numbers in some tissues, leading to the deterioration of tissues and organs, the phenotypes of aging.
View Article and Find Full Text PDFThe immortalization of human B-lymphoblastoid cell lines (LCL) transformed by Epstein-Barr virus (EBV) is accompanied by two major events: increase in telomerase activity and change in karyotype from normal diploid to aneuploidy. We investigated the effect of genetic factors on the incidence of immortalization by putting old and new data together to collect enough samples for statistical analysis. Among 50 LCL from normal individuals, 5 LCL (10.
View Article and Find Full Text PDFWhile the immunosuppressant tacrolimus (FK506) is known to be neuroprotective following cerebral ischemia, the mechanisms underlying its neuroprotective properties are not fully understood. To determine the mode of action by which tacrolimus ameliorates neurodegeneration after transient focal ischemia, we therefore evaluated the effect of tacrolimus on DNA damage, release of cytochrome c, activation of microglia and infiltration of neutrophils following a 60-min occlusion of the middle cerebral artery (MCA) in rats. In this model, cortical brain damage gradually expanded until 24 h after reperfusion, whereas brain damage in the caudate putamen was fully developed within 5 h.
View Article and Find Full Text PDFThe effect and safety of combination prophylaxis for hepatic veno-occlusive disease (VOD) following stem cell transplantation (SCT) was retrospectively evaluated in a total of 53 children who survived until day 30. Prophylaxis was started on the day before conditioning, and heparin (10 unit/kg/hr) alone was used in 6 patients, PGE1 (5 ng/kg/min) plus heparin plus PTX (200 mg/day) in 17 patients, lipo-PGE1 (0.5 ng/kg/min) plus heparin plus PTX in 7 patients, and lipo-PGE1 plus heparin in 23 patients.
View Article and Find Full Text PDFEpstein-Barr virus (EBV) is closely associated with the generation of various tumors, including Burkitt's lymphoma. Human resting B cells from peripheral blood are easily transformed by EBV to actively proliferating B-lymphoblastoid cell lines (LCLs). These LCLs with normal diploid karyotypes have been believed to be "immortal", without becoming tumorigenic.
View Article and Find Full Text PDFTo establish a method for quantitative analysis of HM-1 killer toxin (HM-1), two purified mouse monoclonal antibodies, 1F1 and 4A2, and rabbit polyclonal antiserum against HM-1 were prepared. Both monoclonal antibodies were classified as IgG1(kappa) subtype, and did not neutralize the killing activity of HM-1. By SPOTs analysis, the epitope of 1F1 was found in the sequence of CDPNTG with a corresponding sequence of 11-16 from N-terminal amino acid residues of HM-1, but the epitope of 4A2 was not determined.
View Article and Find Full Text PDFBloom syndrome and ataxia-telangiectasia are autosomal recessive human disorders characterized by immunodeficiency, genome instability and predisposition to develop cancer. Recent data reveal that the products of these two genes, BLM and ATM, interact and function together in recognizing abnormal DNA structures. To investigate the function of these two molecules in DNA damage recognition, we generated double knockouts of ATM(-/-) BLM(-/-) in the DT40 chicken B-lymphocyte cell line.
View Article and Find Full Text PDFBackground: Threatened premature labor (TPL) often results in preterm birth (PB). The aim of the present study was to evaluate the associations of periodontal and general health conditions with TPL and PB in relation to serum cytokine levels and the composition of subgingival plaque.
Methods: Eighty-eight women were enrolled in the study.
We studied tumorigenic and phenotypic characteristics of pre- and postimmortal human B-lymphoblastoid cell lines (LCLs) transformed by Epstein-Barr virus (EBV): preimmortal LCLs showed low telomerase activity and a normal diploid karyotype while postimmortal LCLs showed much higher telomerase activity and maintained a clonal aneuploidic state. Among five postimmortal LCLs tested, LCLs N0005 and N6803 formed colonies in agar medium and showed marked aneuploidy, and N6803 was transplantable into nude mice indicating that it had a complete malignant phenotype, but all preimmortal LCLs and the remaining three postimmortal LCLs lacked these characteristics. The products of tumor suppresser genes, p16(INK4A) and pRb, were downregulated in these two LCLs, and the p53 gene was mutated in N0005 LCL.
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