Ribavirin and use of clotting factors in patients with hemophilia and chronic hepatitis C.
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Biomedical subjects
Publications and source records attributed to Junki Takamatsu.
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Thrombotic cardiovascular diseases increase in incidence in the elderly, a tendency dependent on the age-related changes in vascular and hemostatic systems that include platelets, coagulation, and fibrinolytic factors as well as in the endothelium. The hypercoagulability of and advanced sclerotic changes in the vascular wall may contribute to the increased incidence of thrombosis in the elderly. One of the important key genes for aging-associated thrombosis is plasminogen activator inhibitor-1 (PAI-1), a principal inhibitor of fibrinolysis. The expression of PAI-1 is not only elevated in the elderly but also significantly induced in a variety of pathologies associated with the process of aging. These conditions include obesity, insulin resistance, emotional stress, immune responses, and vascular sclerosis/remodeling. Several cytokines and hormones, including tumor necrosis factor-alpha, transforming growth factor-beta, angiotensin II, and insulin, positively regulate the gene expression of PAI-1. The recent epidemic in obesity with aging in the industrialized society may heighten the risk for thrombotic cardiovascular disease because adipose tissue is a primary source of PAI-1 and cytokines. Emotional or psychosocial stress and inflammation also cause the elevated expression of PAI-1 in an age-specific pattern. Thus, PAI-1 could play a key role in the progression of cardiovascular aging by promoting thrombosis and vascular (athero)sclerosis. Further studies on the genetic mechanism of aging-associated PAI-1 induction will be necessary to define the basis for cardiovascular aging in relation to thrombosis.
OBJECTIVE: Although some patients with limb ischemia have recently undergone therapeutic angiogenesis by cell transplantation, their angiogenic potential has not been well characterized. It is also important to evaluate endothelial progenitor cell (EPC) contents in different stem cell sources to choose the best material for therapeutic angiogenesis. METHODS AND RESULTS: We quantitated the mRNA expression of EPC-specific molecules (eg, Flk-1, Flt-1, CD133, VE-cadherin, etc) in bone marrow-derived or peripheral blood-derived mononuclear cells obtained from patients with ischemic limbs, using real-time reverse-transcription polymerase chain reaction technique. The mRNA expression level of EPC markers was significantly lower in the patients than in healthy controls, which was consistent with results of flow cytometric analysis. However, the implantation of autologous bone marrow mononuclear cells increased the circulating EPCs in the peripheral blood of patients. We furthermore revealed the different expression pattern of EPC markers in possible sources for stem cell transplantation, including normal bone marrow, peripheral blood obtained from recombinant granulocyte colony-stimulating factor-treated donor, and umbilical cord blood. CONCLUSIONS: Patients with peripheral obstructive arterial diseases may have lower angiogenic potential because of decreased expression of EPC specific molecules in their marrow and blood. Therapeutic angiogenesis by transplantation of autologous marrow mononuclear cells increased circulating EPCs in the patients and improved ischemic symptoms.
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The prevalence and clinical implications of occult hepatitis B virus (HBV) infection were investigated in the Japanese patients with hemophilia in whom a high prevalence of infection with transfusion-transmissible viruses has been reported. HBV DNA was detected in the sera of 22 of 43 (51.2%) patients with hemophilia who were negative for HBV surface antigen (HBs), indicating that these patients had occult HBV infection. No factor, including age, type or severity of hemophilia, presence of HBs or HBV core (HBc) antibody, or coinfection with hepatitis C virus (HCV) or human immunodeficiency virus (HIV) was associated with occult HBV infection, except for high anti-HBc titer and/or coinfection with HCV genotype 1 (1a or 1b). In general, occult HBV infection did not appear to have significant clinical implications. However, in patients in whom HBV was detected by PCR specific for the surface (S)-region, higher alanine aminotransferase levels were observed. The genotype of the occult HBV in the present study was exclusively the domestic type indigenous to Japan (genotype C), suggesting a different route of transmission for HBV in comparison to HCV and HIV in this population.
BACKGROUND: The association between Helicobacter pylori infection and idiopathic thrombocytopenic purpura (ITP) has been reported widely. We investigated the prevalence of H. pylori infection, its virulence profile and the effectiveness of its eradication in patients with ITP. MATERIALS AND METHODS: Twenty patients with ITP, 20 with peptic ulcer (10 gastric ulcer (GU), 10 duodenal ulcer (DU)) and 20 with NUD were studied. The virulence profile of the strains was assessed by genotyping for cagA, vacA, iceA, and hpyIIIR/hrgA and by assaying for IL-8 and DNA fragmentation after incubation with AGS cells. Infected patients and two uninfected ITP patients received triple therapy and platelets were counted before and 1 month, 6 months, 1 year, and 2 years after eradication therapy. RESULTS: H. pylori infection was found in 17 ITP (85%), 20 ulcer (100%) and 13 NUD (65%) patients. Biopsies and strains were collected from five ITP, 20 ulcer and 13 NUD patients. The ITP patients had a pangastritis or corpus-predominant gastritis pattern. All H. pylori isolates, from ITP, ulcer and NUD patients, were cagA(+) and vacA s1/m1, and did not differ in levels of IL-8 induction or DNA fragmentation. Fifteen ITP (88%) and 17 ulcer (85%) patients had successful eradication of H. pylori. Ten of these 15 (67%) H. pylori-eradicated ITP patients had platelet recovery. There was no significant change in platelet count in the two ITP patients in whom eradication failed or in the two originally H. pylori-uninfected ITP patients, or in the treated ulcer patients. Age at onset of ITP was the main determinant of platelet recovery: 100% of patients diagnosed after the age of 60 recovered compared with only 22% of those diagnosed before 50. CONCLUSIONS: H. pylori-infected ITP patients have a corpus-predominant pattern of gastritis but the virulence profile of their strains does not differ from that of ulcer or NUD patients. Eradication of H. pylori infection is a good therapeutic option for some patients with chronic ITP, especially for those who develop ITP in older age.
Eight distinct and potentially causative mutations were identified in eight unrelated Japanese patients with protein S (PS) deficiency, by direct DNA sequencing of the protein Salpha (PSalpha) gene-specific polymerase chain reaction products of all 15 exons and exon/intron boundaries. There were five missense mutations, including two novel mutations (Cys80Tyr and Arg314His), and three showed a major impact on the expected gene products: novel mutations of a 5-bp deletion (delCTCTG887:Cys206Stop) and a nonsense mutation (Glu208Stop), as well as a previously reported splice site (exon 10 +5 A-->G) mutation. One of the patients showed compound heterozygosity for delCTCTG887 and 732A-->G. Investigation for the cosegregation state of these two mutations with PS deficiency in the patient's family suggested that the delCTCTG887 mutation was responsible for the abnormal phenotype and that the 732A-->G (Lys155Glu) mutation did not appear to play a key role. However, we also identified the same 732A-->G (Lys155Glu) mutation in an unrelated patient with apparent PS deficiency with severe pulmonary embolism, and found that this mutation seemed to cosegregate with a PS-deficient state in her family members. These data implied that unknown factor(s) other than the 732A-->G mutation itself might influence phenotypic expression of PS status in different individuals.
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GB virus C (GBV-C) or hepatitis G virus (HGV) has been transmitted to Japanese patients with hemophilia through the frequent use of unheated blood products. Sequence analysis showed that most of the viruses isolated from these patients belonged to GBV-C/HGV genotype 1, which is usually found in persons from Africa. This may point to the origin of this virus in Japanese patients with hemophilia. The phylogeny of 11 GBV-C/HGV isolates from Japanese patients with hemophilia was investigated by a detailed analysis with a fragment spanning from the 5' non-coding region to part of the E1 gene. Except for one that belonged to the genotype 3 cluster, all isolates were GBV-C/HGV type 1. Five main clades exist within the GBV-C/HGV genotype 1 sequences. These isolates are grouped in 2 defined clades. Three of the isolates are clustered in subtype 1c clade whereas the other 7 strains formed a new statistically well-supported monophyletic group (named subtype 1e). Our results suggest that GBV-C/HGV type 1 can at present be classified into at least 5 clades and in this group a majority of Japanese patients with hemophilia was infected with a GBV-C/HGV of a unique and newly described subtype within genotype 1.
Hepatitis C virus (HCV) can be classified into six major genotypes, the prevalences of which differ around the world. In Japan, the main genotypes are HCV 1 and HCV 2; others are found only rarely. Little is known about the prevalence in Japan of HCV genotype 4 which, is found frequently in North and Central Africa and the Middle East. Thus, we conducted a study to clarify distribution of HCV genotype 4 and the clinical demographics of patients with HCV genotype 4 in Japan. We examined HCV genotypes in 899 Japanese individuals with HCV viremia living in Aichi Prefecture, including 63 hemophiliacs. Four patients (0.4%) were infected with HCV genotype 4. All four of these patients were male hemophiliacs who had received clotting factors from foreign countries. Three patients were co-infected with human immunodeficiency virus (HIV); none were co-infected with GB virus-C/hepatitis G virus. Phylogenetic analysis of the El region indicated that all four patients were infected with subtype 4a. This subtype is related genetically to a subtype previously reported in Japanese and Italian hemophiliacs. HCV genotype 4 is indeed rare in Japan and may be detected only among hemophiliacs who have received inactivated clotting factor concentrates from foreign countries.
A new method for hepatitis C virus (HCV) genotyping that analyzes products generated with the HCV Amplicor Monitor Test has been developed. One hundred and sixty-two Japanese patients with chronic hepatitis C, including 59 patients with hemophilia, were tested for HCV genotypes and viral loads with this new test, and the results were compared with those of a genotyping assay that involved direct sequencing of the E1 region. HCV genotypes and viral loads were also compared between patients with and without hemophilia. There were no discrepancies between the two methods in determining genotypes 2a, 2b, and 3a. However, two patients infected with 1a were mistyped as 1b with the new assay. One patient not classified by this assay was genotype 4. Genotypes found in patients without hemophilia were 1b, 2a, and 2b. Genotypes 1a, 3a, and 4, which were minor variants in Japan, were detected only in patients with hemophilia. In addition, J type, which is a subtype of 1b that originated in Japan, was found at low frequency in hemophiliacs. Thus, the HCV genotypes in patients with hemophilia are likely to be of foreign origin. Overall, this new assay was accurate except for genotype 1a and 4, and allowed simultaneous assessment of genotype and viral load.
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A randomized prospective double-blind trial was performed to compare the safety and efficacy of human activated protein C (APC) and unfractionated heparin for the treatment of disseminated intravascular coagulation (DIC). One hundred thirty-two patients with DIC were enrolled in this study: 63 patients received APC (12.5 U [2.5 microg]/kg body wt per hour) and 69 patients received heparin (8 U/kg body wt per hour) by intravenous infusion for 6 days. Forty-nine APC-treated patients and 55 heparin-treated patients were evaluated for efficacy, and 52 APC-treated patients and 55 heparin-treated patients were evaluated for safety. The 2 groups were similar with respect to sex, age, body weight, underlying diseases, and coagulation/fibrinolysis parameters before treatment. Aggravation of bleeding was seen after treatment in 8 patients receiving heparin, but in none of the patients receiving APC. The number of patients who showed alleviation of bleeding was significantly higher in the APC group than the heparin group (P = .009). The effects on DIC-related organ dysfunction were not significantly different between the 2 groups. Fibrinogen-fibrin degradation products, D-dimer, thrombin-antithrombin complex (TAT), and plasmin-plasmin inhibitor complex (PIC) were all significantly decreased by treatment in both groups. Fibrinogen, protein C, and antithrombin were significantly increased in the APC group, whereas only protein C was significantly increased in the heparin group. Platelet count in the nonleukemic group was significantly increased in those patients receiving APC but not increased in those patients receiving heparin. Improvement of coagulation/fibrinolysis was assessed by scoring 4 parameters (soluble fibrin monomers, D-dimer, TAT, and PIC), and the results indicated that the APC group showed significantly greater improvement than the heparin group (P = .046). There was, however, no significant difference in the rate of complete recovery from DIC between the 2 groups. The rate of death from any cause within 28 days after treatment was 20.4% in the APC group, significantly lower than the 40% death rate observed in the heparin group (P < .05). There were no severe adverse events in either group. These results suggest that APC in a relatively small dosage can improve DIC more efficiently than can heparin, without increasing bleeding, and may be a better alternative.
The hematopoietic toxicity of ethylene glycol monomethyl ether (EGME) and its metabolites, methoxy acetaldehyde (MALD) and methoxyacetic acid (MAA), was analyzed using human bone marrow cells from a lymphoma patient without bone marrow involvement and a human leukemia cell line, HL60. After 24-hour incubation, the concentrations of 50 percent inhibition (IC50) of human hematopoietic progenitor cells with MALD or MAA were 3 mM and 3.9 mM, respectively, and EGME (10 mM or more) did not show any cytotoxicity. IC50 (after 48-hour exposure) of MALD and MAA on HL60 cells were 2.45 mM and 5.6 mM, respectively, suggesting that both hematopoietic progenitor cells and HL60 have a similar sensitivity. DNA ladder formation, a characteristics of apoptosis, was observed in MALD- or MAA-treated HL60 cells, but not in EGME-treated samples. Caspase-3 enzyme activity, the effector of the apoptotic process, was greatly enhanced with MALD treatment. The inhibitor of caspase-3 repressed cell death induced with MALD as well as MAA.
To investigate influence of HIV co-infection on HCV, we examined 58 Japanese hemophiliacs with chronic hepatitis C(CHC) including 25 patients co-infected with HIV. HCV RNA levels and liver function were not affected statistically by the presence of HIV. Further studies are necessary to evaluate the impact of HIV on the prognosis of CHC in hemophiliacs. We were the first to report a beneficial effect of GBV-C/HGV infection on the course of HIV disease and many studies were confirmed our results. Discussions of these important issues such as impact of HIV on GBV-C/HGV and HBV have been performed in this paper.