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G Dusheiko

Publications and source records attributed to G Dusheiko.

At least 55 records · Page 3Linked to original sources
PubMed1994

The progression of HCV-associated liver disease in a cohort of haemophilic patients.

We have studied morbidity and mortality related to hepatitis C virus infection in haemophilic patients treated at our centre. 11/255 HCV seropositive patients have developed hepatic decompensation. 20 years after first exposure to lyophilized clotting factor concentrate the risk of hepatic decompensation is estimated to be 10.8% (95% CI 3.8-17.8%). There is a significantly increased risk associated with HIV infection, and also with increased age. For HIV seropositive patients the rates of decline in CD4 lymphocyte count and the development of p24 antigenaemia are significant risk factors for hepatic decompensation. Cirrhosis was seen in 9/19 HIV seropositive patients at post mortem. There was an association of cirrhosis with increased age but not with CD4 count, p24 antigenaemia, or AIDS. In conclusion, HCV infection is associated with serious liver disease in haemophilic patients, but so far this has been restricted to a minority of those at risk. HIV co-infection accelerates progression to hepatic decompensation, and we speculate that this is probably due to enhanced HCV replication in the presence of immune deficiency.

Adolescent↗
PubMed1994

Sequence variability of hepatitis C virus and its clinical relevance.

Chronic type C hepatitis is a potentially serious disease that can lead to cirrhosis and hepatocellular carcinoma. This complex disease is caused by the hepatitis C virus (HCV), a positive sense, single-stranded RNA virus. HCV has been assigned to a separate genus within the Flaviviridae, and shares a close relationship to the pestiviruses. Nucleotide sequence variation has been observed in genomes amplified from serum of patients with HCV infection, and cloning of RNA amplified from patients infected with HCV has confirmed the heterogeneity of the agent responsible for post-transfusion and sporadic hepatitis C. The variability of HCV is structured in a way that immediately suggests a two tiered classification: this nomenclature comprises 'types' corresponding to the major branches in a phylogenetic tree of sequences from genomic or subgenomic regions of the genome, and 'subtypes', corresponding to the more closely related sequences within some of the major groups. This genotyping designation has provided an epidemiological tool for studying geographical differences in hepatitis C infection. Clearly discernible patterns of genotype distribution have been found in those countries that have been studied so far. In many European countries genotype distributions vary with the age of patients, reflecting rapid changes in genotype distribution with time within a single geographical area. Unfortunately we know very little about modes of transmission within different communities. There is considerable interest in the clinical significance of different HCV genotypes, and the intriguing question of whether these differences may affect the spectrum of the disease associated with hepatitis C. These data also have implications for diagnosis and treatment of acute and chronic hepatitis C. A uniform typing scheme and nomenclature will facilitate our understanding of the disease caused by this virus worldwide.

Genotype↗
PubMed1994

Selective radionuclide localisation in primary liver tumours (pilot study).

The therapeutic potential of 131I-Lipiodol was investigated in 8 patients with cholangiocarcinoma (CCA) and 15 patients with hepatocellular carcinoma (HCC). Patients received one or two doses of 131I-Lipiodol via hepatic arterial injection. The mean total administered activity was 668 (SD 325) MBq in CCA and 953 (SD 477) MBq in HCC. One patient with CCA retained 131I-Lipiodol. The cumulative radiation dose was 9.6 Gy to tumour, 6.4 Gy to liver and 1.5 Gy to lung. The patient remained asymptomatic with no evidence of tumour 30 months from the start of treatment, whereas the remaining 7 patients exhibited tumour progression. The mean survival in CCA was 11.6 (SD 14.5) months. All 15 patients with HCC retained 131I with tumour: liver ratios of up to 30:1. The mean cumulative radiation dose was 34.7 (SD 32.4) Gy to tumour, 3.3 (SD 1.5) Gy to liver and 4.4 (SD 2.3) Gy to lung. The mean dose per administered activity was 3.8 (SD 4.1) cGy/MBq. Partial response (reduction in tumour size > 50%) was observed in 6 patients (40%). The mean survival was 7.1 (SD 6.0) months. 131I-Lipiodol can deliver highly selective internal irradiation to foci of HCC with evidence of objective response and may be the treatment of choice for patients with cirrhosis and a small tumour.

Adult↗
PubMed1994

Hepatitis C virus genotypes: an investigation of type-specific differences in geographic origin and disease.

Because of the nucleotide sequence diversity of different isolates of hepatitis C virus, it has become important to clarify whether distinct genotypes of hepatitis C virus vary with respect to pathogenicity, infectivity, response to antiviral therapy and geographic clustering. We assessed nucleotide sequence variability in the 5' noncoding region of hepatitis C virus, using restriction enzymes to analyze the distribution of hepatitis C virus genotypes, in 80 patients with chronic hepatitis C virus infection. Genotypes were correlated with demographic, clinical and histological features. Thirty-seven patients were infected with type 1, 10 had type 2 and 8 had type 3, and another 23 were infected with a new distinct hepatitis C virus type now classified as type 4. Two were infected with variants whose classification are uncertain. Types 1, 2 and 3 were found in patients from the United Kingdom, southern Europe, Asia, Africa and South America. Nineteen of 23 type 4 genotype isolates were from Middle Eastern patients, compared with 0 of 37 type 1 isolates (p < 0.001). Of 21 Middle Eastern patients, 19 (90.4%) had type 4 hepatitis C virus (p = 0.001, odds ratio = 9). We found no significant difference between the mean ages or mean serum aminotransferase concentrations between the various types. Types 1, 2, 3 and 4 were found in patients with mild-to-moderate disease or severe disease. However, 21 of 29 (72.4%) patients with type 1 who underwent liver biopsy had severe chronic hepatitis, cirrhosis or hepatocellular carcinoma histologically; 8 had mild or moderate chronic hepatitis without cirrhosis (p = 0.03, odds ratio = 2.6).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Sequence variability in the 5' non-coding region of hepatitis C virus: identification of a new virus type and restrictions on sequence diversity.

We have analysed the pattern of nucleotide sequence variability in the 5' non-coding region (5' NCR) of geographically dispersed variants of hepatitis C virus (HCV). Phylogenetic analysis of sequences in this region indicated the existence of a new virus type, provisionally termed type 4, the identity of which was confirmed by further analysis of the more variable part of the HCV core protein coding region. The geographical distribution of HCV type 4 was distinct from that of other HCV types, it being particularly widespread in Africa and absent or rare in Europe and the Far East. Much of the variability in the 5' NCR appears to be constrained by a requirement for specific secondary structures in the viral RNA. In one of the most variable regions of the 5' NCR (positions -169 to -114), most of the nucleotide changes that are characteristic of different HCV types were covariant, with complementary substitutions at other positions. According to the proposed secondary structure of the 5' NCR, such changes preserved base pairing within a stem-loop structure, whereas the nucleotide insertions found in a proportion of 5' NCR sequences, including those of type 4, localized exclusively to the non-base-paired terminal loop. The specific nucleotide substitutions in the 5' NCR that differentiate each of the four HCV types can be detected by restriction enzyme cleavage, providing a rapid and reliable method for virus typing.

Amino Acid Sequence↗
PubMed1993

Alpha interferon in the treatment of chronic hepatitis C infection in thalassaemia major.

Hepatitis C virus (HCV) is responsible for the majority of cases of post transfusion non-A non-B (NANB) hepatitis in thalassaemia major (TM). Twelve multi-transfused TM patients with serological, biochemical, histological and molecular biological evidence of HCV infection have been treated for 6 months with recombinant alpha-interferon (IFN). Ten (83%) responded as assessed by a fall of at least 50% of pre-treatment serum transaminase levels. Histological improvement was observed in 6/7 responders tested. Natural killer (NK) cell activity 24 h after the first dose of IFN was significantly increased in responders as compared to non-responders (P < 0.05). HCV RNA disappeared from serum in 5/12 and from liver tissue in 2/5 of the responders. The degree of induction of peripheral blood mononuclear cell 2'5' oligoadenylate synthetase messenger RNA (2-5 OAS mRNA), an enzyme induced by IFN, after the first dose of IFN did not correlate with response. IFN was generally well tolerated. We conclude that the response rate in multi-transfused TM patients infected with HCV and treated with IFN is similar to that in non-multi-transfused patients.

Adolescent↗
PubMed1993

Viral markers in the treatment of hepatitis B and C.

Acute hepatitis B virus (HBV) infection is typically distinguished from chronic disease by a positive IgM anti-hepatitis B core antigen (anti-HBc) test. Patients with chronic hepatitis B remain hepatitis B surface antigen (HBsAg) positive, often with raised serum alanine aminotransferase (ALT) activities, for more than six months. The presence of hepatitis B e antigen (HBeAg) and HBV-DNA correlates with infectivity (although patients infected with the pre-core mutated virus may be HBeAg negative). Immunity after HBV infection is characterised by the presence of anti-HBs and anti-HBc antibodies. Patients who respond to interferon alfa treatment lose HBV-DNA and HBeAg from serum and their ALT values return to normal; some also lose HBsAg and acquire anti-HBs. Diagnosis of acute hepatitis C virus (HCV) infection remains largely dependent on history and exclusion, as anti-HCV antibodies may appear late or never at all, although HCV-RNA may be detectable on polymerase chain reaction (PCR) within days of infection. Second generation ELISAs detect a range of anti-HCV antibodies in chronic infections, and confirmatory RIBAs have reduced the incidence of false-positive results. Direct tests for HCV antigens in serum are not yet available, although PCR testing for HCV-RNA can be used to confirm viraemia. Patients who respond to interferon alfa treatment show continuous normalisation of serum ALT values, and some lose HCV-RNA. Relapse occurs in about half of all those who respond.

Biomarkers↗
PubMed1993

Recombinant alpha 2B interferon (IFN) in the treatment of chronic hepatitis C disease in thalassaemia major (TM).

Hepatitis C virus (HCV) is responsible for the majority of cases of post transfusion non-A non-B (NANB) hepatitis in thalassaemia major (TM). Fifteen multi-transfused TM patients with serological, biochemical, histological and molecular biological evidence of HCV infection have been treated for six months with recombinant alpha interferon (IFN). Eleven (73%) responded, 8 (53%) had complete response (CR), 3 (20%) partial response (PR) and 4 (27%) did not respond (NR) to IFN. Natural killer (NK) cell activity 24 hours after the first dose of IFN was significantly increased in responders as compared to non-responders. Liver histology showed an overall reduction of portal inflammation and periportal necrosis in the responding patients. HCV RNA disappeared from serum in 8 (15) responders and partial responders. Non responders remained positive. HCV RNA was tested and found to be positive in liver tissue material in 7 patients, five of those were re-tested after IFN treatment. Two became negative (both CR) 3 remained positive despite biochemical response to IFN. The degree of induction of peripheral blood mononuclear cell 2'5' oligoadenylate synthetase messenger RNA (2-5 OAS mRNA), an enzyme induced by IFN, after the first dose of IFN did not correlate with response neither was any significant interaction with cytokines observed; tumour necrosis factor (TNF), interleukin-1. (IL-1) and CD4:CD8 ratios did not change. We conclude that IFN should be given to all TM patients with chronic active hepatitis due to HCV.

Adolescent↗
PubMed1992

Absence of hepatitis B virus precore mutants in patients with chronic hepatitis B responding to interferon-alpha.

Precore defective HBV mutants may gradually prevail because of immune selection and explain spontaneous seroconversion from HBeAg to anti-HBe in HBV carriers. We have analyzed whether the presence of precore HBV mutants is a determinant of responsiveness to interferon-alpha therapy. Fifteen carriers (nine responders and six nonresponders) who were treated with interferon-alpha were examined. Serum samples were collected before and after therapy. After extraction of DNA, the precore region was amplified by the polymerase chain reaction, and the product was identified by gel electrophoresis and ethidium bromide staining and then Southern blotting and molecular hybridization. The amplified products in all patients were asymmetrically amplified by a modified polymerase chain reaction, and the precore region was directly sequenced. All patients were HBV DNA positive initially. Circulating HBeAg-negative mutants were not identified before treatment in either responders or nonresponders. All nine responders were negative for HBV DNA in serum by dot blot during or after treatment, but seven remained positive by polymerase chain amplification and Southern-blot hybridization. All of the nonresponders remained positive for HBV DNA by dot blot. A silent mutation involving the substitution of an A for G at position 1888 was found in seven carriers; however, no HBeAg-negative mutants were detected in the follow-up of either responders or nonresponders to interferon-alpha.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Increased steady-state levels of alpha-fetoprotein mRNA in hepatocellular carcinoma: an analysis by in situ hybridization.

The molecular basis for the augmented production of alpha-fetoprotein is unknown. We have used in situ hybridization of alpha-fetoprotein cDNA to malignant hepatocytes to establish if increased serum alpha-fetoprotein concentrations are related to detectable steady-state levels of alpha-fetoprotein mRNA in hepatocytes. Tumor tissue from four patients with histologically confirmed hepatocellular carcinoma were examined, and the results compared to fetal liver. Northern blot hybridization for alpha-fetoprotein mRNA in tumor tissue was also analyzed. As expected a high number of grains was observed in fetal liver tissue, indicative of high levels of alpha-fetoprotein mRNA physiologically present during pre-natal development. Sections from all patients with high serum concentrations of alpha fetoprotein showed appreciable hybrid formation, which correlated semi-quantitatively with the serum concentrations. However, hybrids were not detected in a patient with a normal serum alpha-fetoprotein. The high alpha-fetoprotein mRNA levels in fetal and neoplastic liver suggest that gene transcription is the mechanism of alpha-fetoprotein production in malignancy, although the control of this mechanism remains speculative.

Adult↗
PubMed1992

Viral hepatitis.

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Acute Disease↗
PubMed1991

Hepatitis C virus.

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Blood Donors↗
PubMed1991

Selective regional chemotherapy of unresectable hepatic tumours using lipiodol.

Over a 30 month period from 1987 to 1990, selective hepatic cannulation under fluoroscopic control was performed in 57 consecutive patients with primary and secondary malignancies of the liver. Fifty-three patients were subsequently treated using intra-arterial Lipiodol emulsified with epirubicin. The tumours treated were hepatocellular carcinoma (n = 35), metastatic adenocarcinoma (n = 14), intrahepatic cholangiocarcinoma (n = 3) and leiomyosarcoma (n = 1). For hepatocellular carcinoma the cumulative survival was 38% at one year; the median survival was 12.2 months for Stage I, 6.3 months for Stage II and 0.9 months for Stage III tumours. In metastatic disease the cumulative survival was 63% at one year. These data suggest that targeted intra-arterial chemotherapy with Lipiodol-epirubicin is a useful palliative therapy for patients with Stage I and II HCC, and that a controlled trial of this treatment should be undertaken.

Adenocarcinoma↗
PubMed1991

Thyrotropin receptor antibodies following treatment with recombinant alpha-interferon in patients with hepatitis.

We measured thyrotropin receptor antibodies in serum obtained from 2 groups of patients participating in clinical trials of recombinant interferon-alpha 2b for viral hepatitis. Group I: Patients with hepatitis B (N = 8), received interferon 5 x 10(6) units thrice weekly for 4 months. Group II: Patients with non-A, non-B hepatitis (N = 16) were randomized to receive interferon in a dose of either 0.25 x 10(6) or 3 x 10(6) U thrice weekly for 6 months and then crossed over to receive the other dosage schedule for a further 6 months. None of the patients developed thyrotoxicosis. Thyrotropin receptor antibody activity was detectable within the "normal range" (less than 10 U/l) in 6 patients prior to treatment. In Group I, thyrotropin receptor antibodies became detectable in 6 patients on treatment, in 4 of whom it was 10 U/l. In Group II, thyrotropin receptor antibody activity was unchanged on low-dose interferon, but on the higher dose became detectable in 9 patients, in 7 of whom it was greater than 10 U/l. We conclude that treatment with interferon is associated with the development of thyrotropin receptor antibodies in a large proportion of patients. It is possible that in some patients treated with higher doses of interferon the increase in thyrotropin receptor antibody activity may be sufficient to induce hyperthyroidism.

Adult↗
PubMed1991

Liver transplantation for chronic viral hepatitis.

Liver transplantation remains a problem for end stage liver disease due to chronic viral hepatitis, in contrast to the success with fulminant hepatitis B, D and C in which recurrence of viraemia is relatively rare. Following transplantation for chronic HCV disease recurrence of hepatitis C is infrequent and does not appear to be an important clinical problem. The complete picture will only be described when a suitable HCV-RNA test becomes routinely available. Patients with cirrhosis due to hepatitis B, with low levels of viraemia, or patients with hepatitis D are less likely to develop reinfection than those with high levels of HBV viraemia. The use of hepatitis B immunoglobulin in high doses for prolonged periods delays rather than prevents recurrence. It is a very expensive ancillary treatment. Patients with chronic hepatitis D related cirrhosis in whom levels of hepatitis B replication are suppressed, have a low recurrence rate even without immunoglobulin prophylaxis although HDAg remains in the liver. Hepatitis only reoccurs with recurrence of HBV infection. Unfortunately transplantation of HBV DNA and HBeAg positive patients has many shortcomings, and reinfection of the engrafted liver and subsequent development of hepatitis B is common. Survival rates are reduced in this latter group. At present there are no firm recommendations that can be given to prevent recurrence: HBIG in large doses and for prolonged periods would appear to be insufficient to prevent reinfection and these patients often die of recurrent disease. A major challenge for transplant groups will be the prevention of viral reinfection particularly in this latter group.(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic Disease↗