bluuebunny/crossref_metadata_2025 huggingface dataset:
Hepatitis C virus quasispecies and response to interferon therapy in patients with chronic hepatitis C: a prospective study
Authors: Hino  , Yamaguchi  , Fujiwara  , Katoh  , Korenaga  , Okazaki  , Okuda  , Okita  ,   the Yamaguchi Hepatitis C Research Group
Published: March 2003

We prospectively examined whether the complexity of hepatitis C virus (HCV) quasispecies is related to the response to interferon (IFN) therapy. Among 64 patients who had histologically proven chronic hepatitis and were treated with natural IFN‐α, 53 patients were analysed. The other 11 patients discontinued therapy because of adverse effects of IFN. The complexity of the hypervariable region 1 (HVR 1) in quasispecies was determined using both clone number determined by fluorescence single‐strand conformation polymorphism (SSCP) and nucleotide diversity determined by direct sequencing. These parameters were measured not only before treatment but also at completion and 6 months after therapy, if serum HCV RNA was detectable. This population of patients was different from the general Japanese population with regard to the high prevalence of patients infected with genotype 2a or 2b (49%), who had a higher viral load than those with genotype 1b (P = 0.021). Twenty‐two patients (41.5%) were sustained responders. Genotype non‐1b (P = 0.0009) and a smaller clone number (P = 0.008) were significantly associated with a sustained response. In multivariate analysis, these variables were independently associated with a sustained response (i.e. genotype: odds ratio 6.84, 95% CI 1.84–30.12; and clone number: odds ratio 1.26, 95% CI 0.99–1.68). The clone number and nucleotide diversity did not change significantly between pretreatment and at completion or 6 months after therapy. These results suggest that lower complexity of HVR 1 quasispecies predicts a preferable response to IFN therapy that is independent of viral load, especially in the population of the relatively high prevalence of patients infected with genotype 2.
Infections with hepatitis B and C viruses in patients on maintenance dialysis in Romania and in former communist countries: yellow spots on a blank map?
Authors: Vladutiu  , Cosa  , Neamtu  , State  , Braila  , Gherman  , Patiu  , Dulau‐Florea
Published: March 2003

We studied prospectively, between 1993 and 1998, the prevalence and incidence of markers against hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV), in 180 patients with chronic renal failure, dialysed in the Nephrological Clinic, Cluj. HBV and HCV markers were common in the patients who were already on haemodialysis in 1993 (antibodies to hepatitis B core antigen [HBcAb]: 57.9–88%; hepatitis B surface antigen [HBsAg]: 8.7–25%; antibodies to HCV [anti‐HCV]: 73.7–100%; simultaneous occurrence of HBsAg and anti‐HCV antibodies: 4.4–21%). These patients had the longest mean duration of haemodialysis therapy (6.79 ± 4.82 years). The lowest prevalence was found in 1996, in the groups of patients included in the haemodialysis programme between 1993 and 1996 (HBcAb: 2.2–3.3%; HBsAg: 0–2.2%; anti‐HCV antibodies: 0–2.2%; HBsAg and anti‐HCV antibodies: 0–2.2%). The patients included since 1996 had, again, a high prevalence of markers (HBsAg: 21.6%; anti‐HCV antibodies: 28.6%), despite the short duration of dialysis therapy (1.65 ± 1.18 years). The incidence of infection was high before 1993, fell markedly between 1993 and 1996 (zero for the HBsAg and 6.67% year−1 for the anti‐HCV antibodies) and rose sharply between 1996 and 1998 (10.2%, respectively 29% year−1). The prevalence of HBV and HCV infections did not correlate with the age of the patients and depended, but only up to 1993, on the quantity of transfused blood. The link between the duration of the haemodialysis and the prevalence of the HBV and/or HCV infection proved nosocomial transmission. The very high prevalence and incidence of HBV and HCV infections, surpassing not only Western countries, but even those of ‘developing’ countries that are endemic for these infections, is characteristic of some former communist countries. A radical reform of the medical system in these countries is required.
Comparison between three quantitative assays in patients with chronic hepatitis C and their relevance in the prediction of response to therapy
Authors: Pradat  , Chossegros  , Bailly  , Pontisso  , Saracco  , Sauleda  , Thursz  , Tillmann  , Vlassopoulou  , Alberti  , Braconier  , Esteban  , Hadziyannis  , Manns  , Rizzetto  , Thomas  , Trépo
Published: March 2003

To compare three quantitative assays measuring viral load in patients with chronic hepatitis C and to determine their value in predicting response to interferon (IFN) therapy, we analysed serum from 896 patients from eight European Centres using QUANTIPLEX™ bDNA, MONITOR AMPLICOR™ and SUPERQUANT™ assays. Analyses were performed on the same sample. Viral genotype was assessed using INNO‐LiPA HCV II kits. Intercentre variations were observed that were related to the handling of specimens not processed and stored within 6 h of blood sampling. Among sera with optimal handling, a stronger correlation was observed between bDNA and SUPERQUANT (0.806) than between bDNA and MONITOR (0.677) and between MONITOR and SUPERQUANT (0.632). These discrepancies were greatest with genotype 2 (bDNA/SUPERQUANT= 0.772; bDNA/MONITOR=0.456; SUPERQUANT/MONITOR= 0.299). This correlation was influenced by viraemia level and was better at lower viral loads. The proportion of sera with undetectable viral load was 15% with bDNA, 9.7% with MONITOR and 7.7% with SUPERQUANT. For the three measurements, the best cut‐offs of sustained response to IFN treatment were located at their detection threshold. Among patients with viral load below the detection level, a sustained response was observed in 35% tested with bDNA, 38% with MONITOR and 80% with SUPERQUANT. Hence a stronger correlation was observed between bDNA and SUPERQUANT than between either of these assays and MONITOR. SUPERQUANT was the most sensitive assay and this greater sensitivity was associated with a better predictive value of treatment response.
The stability of hepatitis C virus RNA after storage at +4 °C
Authors: Gessoni  , Barin  , Frigato  , Fezzi  , De Fusco  , Arreghini  , Galli  , Marchiori
Published: March 2003

One of the major issues in nucleic acid testing is how to store blood samples to obtain reliable results. We therefore studied hepatitis C virus (HCV) RNA concentration in samples after storage at +4 °C or freezing and thawing. Six HCV RNA‐positive, untreated subjects were studied. Blood samples were collected from these subjects in plasma preparation tubes. The HCV RNA concentration was analysed after storage at +4 °C for 168 h or after five freeze–thaw cycles. For HCV RNA quantification we used a qualitative and a quantitative commercial test. After 168 h of storage at +4 °C, the HCV RNA concentration was similar to that observed at time‐point 0 (5.025 log vs 5.492 log). In one sample we observed a significant fall in HCV RNA concentration. After five freeze–thaw cycles, the HCV RNA concentration was lower than that observed at time‐point 0 (4.454 log vs 5.492 log) and in four samples we observed a significant fall in HCV RNA concentration. Our data suggest that HCV RNA is stable in whole blood samples stored at +4 °C for 168 h. Based on our results, we conclude that the standard procedures for transport of blood samples (at room temperature for a maximum of 5 h) and storage schedules (+4 °C for a maximum of 48 h) can be maintained without compromising the quality of results.
Interferon‐α therapy in chronic hepatitis B: early monitoring of hepatitis B e antigen may help to decide whether to stop or to prolong therapy
Authors: Heijtink  , Janssen  , Hop  , Osterhaus  , Schalm
Published: March 2003

Hepatitis B e antigen (HBeAg) was quantified before, during and after interferon‐α administration in a trial of 162 chronic hepatitis B patients treated for 16 or 32 weeks. In 139 of these patients we examined the prognostic value of the pretreatment level of HBeAg and the reduction in HBeAg level at weeks 4 and 8 for response at week 16. Multivariate analysis showed that the HBeAg pretreatment level is a highly significant predictor of response (judged as HBeAg and hepatitis B virus [HBV] DNA negativity), followed by a decrease in HBeAg from the start of therapy to week 8. During the first 8 weeks of therapy, a decrease in HBeAg of less than 40%, as observed in 30% of the patients, consistently resulted in non‐response. After 16 weeks of treatment, non‐responding patients were randomly assigned to receive no further treatment (n=57) or prolonged treatment for another 16 weeks (n=61). In both groups, changes in the HBeAg level from the start of (the first) therapy to week 8, but not the pretreatment HBeAg level itself, were significantly related to the response at week 52 (the end of follow‐up). Changes in the HBV DNA level had no additional predictive value for response at weeks 16 or 52. Therefore, instead of sequential HBV DNA assessment, we recommend monthly monitoring of HBeAg during IFN‐α therapy.
Lamivudine–high dose interferon combination therapy for chronic hepatitis B patients co‐infected with the hepatitis D virus
Authors: Wolters L. M. M. , Van Nunen A. B. , Honkoop P. , Vossen A. C. T. M. , Niesters H. G. M. , Zondervan P. E. , De Man R. A.
Published: March 2003

Currently, the best option for patients with hepatitis delta is interferon alpha therapy for at least one year. To evaluate the effect of the combination lamivudine–high‐dose interferon alpha therapy, we first treated eight patients with chronic hepatitis delta infection with lamivudine for at least 24 weeks; then lamivudine was combined with a high dose of interferon alpha followed by a regular dose (9 MU tiw). Follow‐up was 12 weeks. Virological, biochemical and histological features were evaluated for response to therapy. At baseline, all patients were HBsAg positive in serum and HDV RNA‐(PCR)positive in plasma; HBV DNA was undetectable with the Digene Hybrid Capture assay (limit of detection 1.5 × 106 geq ml–1) in all cases. Transaminases were elevated in all patients; median ALT 68 (range 48–143) IU l–1. Seven of eight patients completed the course; one patient with a pre‐existing sickle cell trait was withdrawn from the trial due to the development of a nephrotic syndrome. The HBsAg‐concentration in serum decreased in two out of seven patients (29%). However, there was no significant decrease in the HBsAg‐concentration in serum during treatment (median 3654 PEU l–1 (range 548–7684) to 5300 PEU l–1 (range 168–19639)). The drop of HDV RNA in plasma from baseline during treatment was not significant. Decrease of HDV RNA was observed in three out of seven patients (43%) (median 105 geq ml–1; range 103–106 to median 103 geq ml–1; range 102–107). Serum ALT did not change as reflected by a median of 68 IU l–1 (range 48–143) at start of therapy to 63 IU l–1 (range 20–171) at the end of therapy. At the end of treatment transaminases had normalised in one patient and decreased in three other patients (improvement in 57%). However, three of these four patients showed a rebound after withdrawal of therapy. The Histology Activity Index (HAI) indicated a drop from a median score of 7 (range 5–9) at baseline to 5 (range 3–8) at the end of treatment, but an increase in fibrosis from a median grade of 2 (range 1–3) at baseline to 3 (range 1–4) at the end of treatment was observed. In conclusion, this study does not yield support for the combination of an HBVsuppressor and 16 weeks of high‐dose interferon for therapy aimed at eradicating the hepatitis delta virus.
Sequence variations of precore/core and precore promoter regions of hepatitis B virus in patients with or without viral reactivation during cytotoxic chemotherapy
Authors: Yeo W. , Zhong S. , Chan P. K. S. , Ho W. M. , Wong H. T. M. , Chan A. S. K. , Johnson P. J.
Published: March 2003

Reactivation of the hepatitis B virus (HBV) is a well‐described complication among cancer patients undergoing cytotoxic chemotherapy. Mutations in the preC/C and the preC promoter regions of HBV have been reported in some patients who developed this condition. A G‐to‐A mutation at nt 1896 in the preC/C region (HBeAg negative/anti‐HBe positive) has been associated with more severe liver disease than that caused by wild type virus. In addition, it has been suggested that patients with these mutations may be more likely to reactivate than those with the wild type virus. Whether or not such mutations were present before the commencement of or developed during the course of cytotoxic chemotherapy is not known. In this study, 28 cancer patients (consisting of 14 consecutive patients who developed HBV reactivation and another 14 who had no reactivation during cytotoxic chemotherapy) are reported. The objectives were firstly, to determine the prechemotherapy HBeAg status and nucleotide sequences of the preC/C and preC promoter regions of HBV in order to determine if these parameters affected the rate of reactivation, and secondly, for those who developed reactivation, to determine whether the mutations were present before chemotherapy or developed during, possibly as a result of, cytotoxic chemotherapy. HBV DNA was amplified by PCR and nucleotide sequencing performed on samples taken prior to chemotherapy and at the time of reactivation. Results revealed that 16 of the 28 patients were HBeAg negative/anti‐HBe positive. Of these 16, four (57%) of the seven patients who had nt 1896 mutation, but only one (17%) of the six who had the wild type HBV genome, developed reactivation. Three had no detectable HBV DNA. In the majority of cases, the type of virus, i.e. wild/mutant at preC/C, that was detected during the reactivation was identical to that detected in the pretreatment samples. With respect to the preC promoter region, the two commonest mutations detected were at nt 1762 (A to T) and nt 1764 (G to A). When this region was translated into amino acid sequences, stop codons leading to truncated X protein at carboxyl terminus were found in four patients, three of whom developed HBV reactivation. We conclude that chronic HBV carriers who are HBeAg negative/anti‐HBe positive with nt 1896 mutation (G to A) may be more likely to develop HBV reactivation during cytotoxic chemotherapy than those with the wild type virus. Cytotoxic chemotherapy does not appear to select out mutant HBV, or to be consistently mutagenic in patients who develop HBV reactivation. The occurrence of stop codons in the amino acid sequences of the X protein in three patients who developed HBV reactivation, including one who was detected only at the time of reactivation, is of particular interest, as such mutant viruses remain replication competent.
Randomized, placebo‐controlled, double‐blind trial with interferon‐α with and without amantadine sulphate in primary interferon‐α nonresponders with chronic hepatitis C
Authors: Teuber G. , Berg T. , Naumann U. , Raedle J. , Brinkmann S. , Hopf U. , Zeuzem S.
Published: March 2003

In primary interferon‐α (IFN‐α) nonresponders with chronic hepatitis C, retreatment with IFN‐α has only limited efficacy with sustained response rates below 10%. Therefore, the aims of the present study were to compare the efficacy and safety of IFN‐α alone or in combination with amantadine sulphate in nonresponders to previous IFN‐α monotherapy. Fifty‐five IFN‐α nonresponders with chronic hepatitis C (mean age: 46.6 years) received IFN‐α 6 MIU thrice weekly for 24 weeks followed by 3 MIU thrice weekly for additional 24 weeks. Amantadine sulphate (n=26) or a matched placebo (n=29) was given orally twice daily for 48 weeks. Because of a low initial response rate at week 12 (13/55 patients) and a high breakthrough rate (8/13 patients) after IFN‐α dose reduction in week 24, a virological end‐of‐treatment response with undetectable serum HCV‐RNA (< 1000 copies/mL) was achieved in only five patients (IFN‐α/amantadine sulphate, one patient; IFN‐α/placebo, four patients). After 24 weeks follow‐up a sustained virological response was observed in only two patients receiving IFN‐α and placebo. Health‐related quality‐of‐life analysis showed a substantial improvement of the Profile of Mood States (POMS) scale concerning the subscales fatigue (P < 0.05) and vigor (P < 0.05) in patients receiving combined IFN‐α/amantadine sulphate treatment compared with those treated with IFN‐α alone. IFN‐α/amantadine sulphate combination therapy was well tolerated without any serious adverse events. In conclusion, retreatment with IFN‐α and amantadine sulphate does not increase the low sustained virological response rates of IFN‐α therapy in primary IFN‐α nonresponders with chronic hepatitis C, but may lead to a sustained improvement of health‐related quality‐of‐life.
Ribavirin treatment in dialysis patients with chronic hepatitis C virus infection – a pilot study
Authors: Bruchfeld A. , Ståhle L. , Andersson J. , Schvarcz R.
Published: March 2003

Standard treatment for chronic hepatitis C is with interferon (IFN)‐α and ribavirin for 6–12 months. In dialysis patients only interferon therapy is currently used due to the lack of knowledge concerning ribavirin dosage and side‐effects. The aim of this study was to investigate if ribavirin can be added to interferon when treating dialysis patients with hepatitis C.

Five patients on haemodialysis and one patient on peritoneal dialysis with chronic hepatitis C, five with genotype 1 and one with genotype 4, were given interferon‐α2b 3 MU thrice weekly for 4 weeks, whereafter ribavirin 200–400 mg was added, for an intended total treatment period of 28 weeks. Ribavirin plasma concentrations were monitored, using HPLC.

Four patients completed the treatment. One patient suffered marked side‐effects from interferon and therapy was terminated. One patient developed heart failure and died after 14 weeks of treatment but the death was not considered treatment related. Based on plasma concentrations, ribavirin doses were frequently adjusted initially. The target concentration (10–15 μmol/L) was reached with average daily doses of 170–300 mg ribavirin. Ribavirin induced anaemia was managed with high doses of erytropoietin (20 000–30 000 IU/week). Five of six patients became hepatitis C virus (HCV)‐RNA negative during treatment, but four relapsed post‐treatment; one is HCV‐RNA negative.

Hence ribavirin, in combination with IFN‐α, can be used to treat dialysis patients with HCV. However, this requires reduced ribavirin doses and close monitoring of ribavirin plasma concentrations and haemoglobin. Ribavirin‐induced anaemia can be managed with high doses of erythropoeitin.
Management of hepatitis C patients by primary care physicians in the USA: results of a national survey
Authors: Shehab T. M. , Sonnad S. S. , Lok A. S. F.
Published: March 2003

Hepatitis C is a major health problem worldwide, yet very little research has been performed to assess the knowledge base and practice patterns of primary care physicians (PCPs) regarding hepatitis C. The aim of this study is to determine the knowledge base and practice patterns of a nationwide cohort of PCPs. A survey was developed to assess the knowledge of PCPs regarding risk factors for hepatitis C, management of hepatitis C patients and attitude regarding testing for hepatitis C. The survey was mailed to 4000 PCPs in the USA. A total of 1412 (39%) PCPs completed the survey. The vast majority, > 90%, of PCPs correctly identified the most common risk factors for hepatitis C. However, only 59% indicated they ask all patients about hepatitis C risk factors, 70% reported they test all patients with hepatitis C risk factors and 78% test all patients with elevated liver enzymes for hepatitis C. Most (72%) PCPs would refer an HCV‐positive patient with elevated aminotransferase but only 28% would refer an HCV‐positive patient with normal aminotransferase to a specialist. One‐fourth of the PCPs did not know what treatment to recommend for hepatitis C patients. Our data suggest that hepatitis C patients may be underdiagnosed and under‐referred. Specific educational initiatives and practice guidelines for PCPs are needed to optimize the recognition of patients at risk for hepatitis C and to ensure appropriate testing and referral.
Predicting response to initial therapy with interferon plus ribavirin in chronic hepatitis C using serum HCV RNA results during therapy
Authors: McHutchison J. G. , Shad J. A. , Gordon S. C. , Morgan T. R. , Ling M.‐H. , Garaud J.‐J. , Albrecht J. K. , Dienstag J. L.
Published: March 2003

In patients with chronic hepatitis C, 48 weeks of therapy with interferon (IFN) plus ribavirin results in a sustained virologic response of 40%. Preliminary analysis suggests that measuring HCV RNA at week 24, rather than week 12, might provide the best prediction of treatment response. To assess the clinical utility of serum HCV RNA determinations at different times during therapy as a predictor of a sustained virologic response we evaluated 912 treatment‐naïve patients. Patients were randomized to receive IFN‐α2b, 3 million units (MU) three times weekly (tiw), for 24 or 48 weeks with either ribavirin or placebo, and then followed for 24 weeks. Serum HCV RNA was measured at weeks 4 and 12 in patients treated for 24 weeks; at 4, 12, and 24 weeks during therapy in those treated for 48 weeks, and week 24 post‐therapy in all patients. Sustained response was defined as loss of serum HCV RNA at week 24 follow‐up. Other patients were considered virologic nonresponders. For patients receiving 48 weeks of combination therapy, detectable serum HCV RNA at week 24 predicted nonresponse (positive predictive value) in 99% of patients compared to 89% at week 12. In patients treated for 24 weeks, testing at week 12 was more predictive of nonresponse than testing at week 4 in the combination‐therapy group but not in the monotherapy group. Hence, for combination therapy, testing for serum HCV RNA as a predictor of nonresponse is most accurate at week 24 of therapy; a positive test correctly identified 99% of nonresponders.
Thymosin‐α1 and famciclovir combination therapy activates T‐cell response in patients with chronic hepatitis B virus infection in immune‐tolerant phase
Authors: Lau G. K. K. , Nanji A. , Hou J. , Fong D. Y. T. , Au W.‐S. , Yuen S.‐T. , Lin M. , Kung H.‐F. , Lam S.‐K.
Published: March 2003

summary. We examined whether combination therapy with thymosin‐α1 and famciclovir would induce hepatitis B e antigen seroconversion in patients with chronic hepatitis B infection in the immune‐tolerant phase without inducing significant hepatic necro‐inflammation. We studied 32 hepatitis B e antigen positive patients in the immune‐tolerant phase of infection, treated with 26‐weeks combination therapy of famciclovir and thymosin‐α1 (group 1). Thirty‐two patients who received 26‐weeks famciclovir monotherapy (group 2) and another 32 patients who received no treatment (group 3), served as controls. Peripheral blood mononuclear cell proliferation and cytokine secretion in response to recombinant HBV core and surface antigen andserial serum HBV‐DNA, were assayed. No significant difference in adverse events were observed among the three groups. By week 26, the median reduction in group 1 (0.94 log10 copies/mL) was greater than group 2 (0.70 log10 copies/mL, P < 0.001). Five (15.6%) patients in group 1 at 52 weeks (median range 13–78 weeks) and none in group 2 or 3 experienced hepatitis B e antigen seroconversion (P = 0.053). Sustained serological clearance of hepatitis B e antigen was associated with activation of CD4 positive HBV‐specific T‐cell reactivity and were of T‐helper 1. Hence combination therapy with immunomodulatory agents and nucleoside analogues should be explored.
Virus‐specific antibody titres in different phases of hepatitis C virus infection
Authors: Nikolaeva L. I. , Blokhina N. P. , Tsurikova N. N. , Voronkova N. V. , Miminoshvili M. I. , Braginsky D. M. , Yastrebova O. N. , Booynitskaya O. B. , Isaeva O. V. , Michailov M. I. , Archakov A. I.
Published: March 2003

summary. This study aimed to examine anti hepatitis C virus (HCV) antibody titres, their changes and differences in acute, chronic and past HCV infection and to examine them after IFN‐α‐therapy. Ninety five patients were studied in a cross‐sectional investigation and 18 of them were followed long‐term. Titres of IgM and IgG antibodies against core, NS3, NS4 (A + B), NS5A proteins were determined by the third generation enzyme immunoassays. Patients with acute hepatitis C developed IgG antibodies against core protein in titres 1/5–1/800 and against individual NS proteins at the same titres. During the first to second month of acute hepatitis C IgG antibody titres to HCV proteins were very low, but they had risen considerably by the fourth to sixth month. Anti‐HCV IgM antibodies were found in half the acute hepatitis serum samples, titres were 1/5–1/40. Sixty individuals with chronic hepatitis C showed IgG antibodies against core in titres 1/800–1/40000 and against individual NS proteins in titres 1/5–1/20000. Eight patients with chronic hepatitis C had invariable anti‐HCV IgG antibodies over 2–3 years. About 81.7% of chronically infected patients had anti‐HCV IgM antibodies in titres 1/5–1/160. Patients with resolution of HCV infection showed only anti‐core IgG antibodies (titres 1/5–1/200) or no virus‐specific antibodies. Individuals with different response to IFN‐α‐therapy showed two distinct patterns of anti‐HCV antibody titres. Acute and chronic HCV infection may be distinguished by anti‐core titres.
Characterization of the immune response against hepatitis C infection in recovered, and chronically infected chimpanzees
Authors: Shata M. T. , Anthony D. D. , Carlson N. L. , Andrus L. , Brotman B. , Tricoche N. , McCormack P. , Prince A.
Published: March 2003

summary. The immune response to hepatitis C virus (HCV) is believed to be critical in determining the outcome of the disease. In this study we have analysed epitope recognition, cytokine profile, and anti‐HCV antibody responses in chronically HCV‐infected and recovered chimpanzees. Quantitative measurement of anti‐HCV antibody in HCV‐infected chimpanzees revealed that the response in HCV‐ recovered chimpanzees peaked within 4–20 weeks. In contrast, the anti‐HCV antibody responses in chronically HCV infected chimpanzees did not peak until 100–200 weeks after infection, and decreased gradually thereafter. T cell proliferation assays measuring responses to pooled HCV proteins revealed significant increases in the 3H‐uptake during the early stages of infection in recovered chimpanzees in comparison to the chronically infected ones. Class I‐restricted epitopes of the core, and NS3 proteins of HCV were analysed using 9–10 mer overlapping peptides covering the core and NS3 proteins, and IFN‐γ ELISPOT technique. Our data indicated early and broad class‐I restricted core, and NS3 protein epitope recognitions in HCV‐recovered chimpanzees but not in chimpanzees that had been chronically infected. Additionally, dominant epitopes recognized early in infection (8 weeks) were no longer recognized later in infection (followed up to 64 weeks). Cytokines profiling revealed a 50‐fold increase in TNF‐α secretion in the supernatant of core‐specific CD8 memory cells of the chronically infected chimpanzees in comparison to the recovered ones. In summary, multiple parameters correlate with HCV recovery in chimpanzees.
Lower expression of CD81 B‐cell receptor in lymphoproliferative diseases associated with hepatitis C virus infection
Authors: Cacoub P. , Bourlière M. , Hausfater P. , Charlotte F. , Khiri H. , Toci S. , Piette J. C. , Poynard T. , Halfon P.
Published: March 2003

summary. Chronic hepatitis C virus (HCV) infection is frequently associated with type II mixed cryoglobulinaemia (MC), a benign lymphoproliferative disease (LPD). More recently, HCV has been implicated as a possible aetiologic factor of B‐cell non‐Hodgkin lymphoma (B‐NHL). CD81, a B‐cell surface receptor, has been proposed as a receptor for HCV binding and entry in circulating B cells. The stimulation of CD81 complex enables B cells to respond to lower concentrations of antigen and finally induces B‐cell proliferation. We studied the phenotypic expression of CD81, CD19 and CD5 on circulating B cells in HCV patients LPD‐positive or LPD‐negative. Sixty‐two patients were anti‐HCV antibody positive. Among HCV positive patients, 44 were HCV RNA positive with an histologically proven chronic active hepatitis of whom 10 had a B‐NHL, 14 an MC and 24 no extrahepatic manifestation. Eighteen patients were HCV RNA negative with evidence of resolved infection. A control group included 40 healthy subjects. Peripheral blood mononuclear cells (PBMC) were stained for surface expression of CD81, CD19 and CD5 using monoclonal antibodies, and were analyzed by flow cytometry. The percentage of PBMC expressing CD81, CD19 and CD5 receptors were compared between the groups by univariate analysis. Logistic regression model variables were then evaluated to correlate the presence of an LPD with HCV infection characteristics (i.e. age, gender, genotype, duration of infection, HCV RNA positivity, liver histological lesions), or phenotypic expression of CD81, CD19 and CD5 receptors on PBMC. HCV antibody‐positive compared with HCV‐negative subjects had a higher expression of CD19 receptor (23 ± 13 vs 13 ± 1%, P = 0.003). Among HCV RNA positive‐patients, LPD+ compared with LPD– patients had a lower expression of CD81 (58 ± 28 vs 82 ± 18%, P = 0.001) and CD5 receptor (66 ± 16 vs 74 ± 13%, P = 0.04). In multivariate analysis, the expression of CD81 receptor was a negative (OR = 0.15, 95% CI  = 0.04–0.64, P = 0.01) and CD19 receptor a positive (OR = 4.81, 95% CI  =1.29–17.88, P = 0.02) predictive factor for an LPD. We found two negative predictive factors for HCV RNA positivity, i.e. age (OR = 0.23, 95% CI. = 0.08–0.62, P = 0.003) and the expression of CD81 receptor (OR = 0.34, 95% CI  = 0.13–0.89, P = 0.02). In patients with a chronic active HCV infection, the presence of a lymphoproliferative disease, either MC or B‐NHL, is associated with lower expression of CD81 and higher expression of CD19 receptor on peripheral B cells.
Long‐term liver histology improvement in patients with chronic hepatitis C and sustained response to interferon
Authors: Toccaceli F. , Laghi V. , Capurso L. , Koch M. , Sereno S. , Scuderi M. ,   The Italian Hepanet Group
Published: March 2003

summary.  A retrospective multicentre survey was conducted to evaluate, in patients with chronic hepatitis C, the long‐term liver histological changes induced by interferon (IFN). A total of 112 patients (mean age 46.4 years) were studied. All patients had received a 6–12‐month IFN‐α course (6–18 MU/week) and had successively undergone clinical, biochemical and virological follow‐up for at least 36 months (range: 36–76). In each patient, two liver biopsies had been performed: 1–6 months before treatment and, 12–76 months after its completion. In 87 patients with biochemical and virological sustained response persisting for 12 months after therapy, post‐treatment liver necroinflammation and fibrosis mean(±SD) scores (Knodell index) were significantly lower than pretreatment scores (2.9 ± 2.2 vs 6.8 ± 2.9 and 0.8 ± 1.0 vs 1.2 ± 1.1, respectively; P < 0.01) . In 25 patients who relapsed within 1 year, necroinflammation and fibrosis post‐treatment mean scores were similar to pretreatment scores (7.4 ± 3.2 vs 6.9 ± 3.1 and 1.8 ± 1.3 vs 1.6 ± 1.2, respectively; P > 0.05). On an individual basis, necroinflammation decreased in 87% of sustained responders but only in 36% of relapsers (P < 0.001), whereas fibrosis decreased in 44% of sustained responders but only in 14% of relapsers (P < 0.001). In sustained responders with biopsies performed 12–23 months (n=34), 24–35 months (n=26) or more than 36 months (n=27) after treatment, a progressive decrease of mean necroinflammatory score was observed (−2.6 ± 2.1, −4.1 ± 3.4 and −5.2 ± 3.7 points, respectively; P < 0.01). A similar pattern was observed in fibrosis score (−0.3 ± 0.6, −0.3 ± 0.7 and −0.7 ± 0.9 points, respectively; P < 0.05). Hence, among chronic hepatitis C patients treated with IFN, those with a 12‐month sustained response, unlike those who relapse, have a long‐term progressive reduction and, in some cases, a complete regression of liver histological damage.
Hepatitis B in St Petersburg, Russia (1994–1999): incidence, prevalence and force of infection
Authors: Beutels Ph. , Shkedy Z. , Mukomolov S. , Aerts M. , Shargorodskaya E. , Plotnikova V. , Molenberghs G. , Van Damme P.
Published: March 2003

summary. Hepatitis B (HB) is thought to be an expanding health problem in Russia. The incidence of infection was estimated from mandatorily reported HB cases in St Petersburg. The two‐sided t‐test for independent samples and the LOESS (locally‐weighted regression) smoother were used to compare the age at infection for symptomatic, asymptomatic and chronic infections, by gender. The force of infection was estimated from seroprevalence data (907 sera taken in 1999) using a newly developed nonparametric method based on local polynomials, as well as an earlier method based on isotonic regression and kernel smoothers. With the local polynomial method, pointwise confidence intervals (95%) were constructed by bootstrapping. On average, men contracted HB infection at a significantly younger age than women (in 1999, 21.8 vs 22.7 years, respectively). The overall male to female ratio was 1.92. In 1999 the overall incidence almost doubled compared with the preceding years and tripled among the age groups with highest incidence (15–29‐year olds: 85% of cases in 1999). The incidence increase was associated with a lower average age at infection (24.1 years in 1994 vs 22.1 years in 1999). The age and gender‐specific force of infection estimates generally confirmed the incidence estimates and emphasized the usefulness of local polynomials to do this. Hence HB transmission in St Petersburg occurs mainly in young adults. The dramatic increase of infections in 1999 was probably due to injecting drug use. Without intervention, HB virus is expected to continue to spread rapidly with a greater proportion of female infections caused by sexual transmission. These trends may also provide an indication for HIV transmission.
Is there a future for elephants in West Africa?
Authors: Barnes R. F. W.
Published: March 2003

The elephants of West Africa have experienced a long history of human disturbance. Before 1800 they were much affected by the precolonial empires of the savanna and Sahelian zones, the trans‐Saharan trade routes, and the coastal trade established by the Europeans. During the 19th century, the increasing demand for ivory from Europe and North America, the European penetration of the region, and the evolution of breech‐loading rifles devastated the remaining elephants. The elephant population of West Africa collapsed before the outbreak of World War I because of intense hunting for ivory. This collapse pre‐empted the decline that would have occurred anyway due to the rapid growth of the human population and consequent loss of habitat. Elephants now find themselves in about 70 small isolated populations that cover only 5% of the region. These fragments are very vulnerable – whether in the arid lands or the humid forests – to poaching and general human disturbance. There are few data on numbers; most of the population estimates are guesses. Two‐thirds of the populations are thought to consist of fewer than 200 animals and therefore have a low probability of surviving the next century.

As more habitat is lost to human activities, West African elephants will soon remain only in protected areas. But many parks and reserves are managed poorly and cannot offer effective protection; they do not guarantee a future for elephants. In addition, their crop‐raiding habit makes elephants unpopular in rural communities surrounding protected areas. Human populations are expected to continue growing and resources for conservation are scarce. The future of West African elephants lies in a small network of well‐protected areas.
Permethrin‐impregnated bednet effects on resting and feeding behaviour of lymphatic filariasis vector mosquitoes in Kenya
Authors: BØGH CLAUS , PEDERSEN ERLING M. , MUKOKO DUNSTAN A. , OUMA JOHN H.
Published: March 2003

The impact of permethrin‐impregnated bednets on resting and feeding behaviour of mosquito vectors of Wuchereria bancrofti, causing human lymphatic filariasis was studied in six pairs of villages (treated and untreated) before and after intervention. The study villages were in Kwale District, near the coast of Kenya, where Bancroftian filariasis is highly endemic, transmitted by a combination of both anopheline and culicine mosquito vectors. Mosquitoes were collected weekly in each village, indoors (using pyrethrum spray catches) and outdoors (using pit traps) during 3–4 months following the long rainy season. Of the filariasis vector species of mosquitoes collected in 1994 before intervention, 33.6% were members of the Anopheles gambiae complex, 30% were An. funestus and 36.4% were Culex quinquefasciatus. PCR analysis of the An. gambiae complex species collected in 1995 demonstrated that 98.5% were An. gambiae sensu stricto, 1% An. arabiensis and 0.5% An. merus.

Introduction of impregnated bednets in 1995 significantly reduced the number of indoor‐resting An. gambiae s.l. by 94.6% and An. funestus by 96.7%, but there was no change in the number of Cx quinquefasciatus collected indoors. The number of outdoor‐resting An. gambiae s.l. was significantly reduced, whereas densities of An. funestus and Cx quinquefasciatus remained unaffected outdoors. ELISA analysis of mosquito bloodmeals showed a shift from human to animal feeding after the introduction of treated nets. The human blood index (HBI) for indoor resting Cx quinquefasciatus was reduced from 93.1% to 14.4%. Vector potential based on the HBI and mosquito density was estimated to be reduced by 99% for An. gambiae s.l., 98% for An. funestus and 97% for Cx quinquefasciatus and vectorial capacity would be suppressed even more by the impact on the vector survival rates (not measured). These results suggest that permethrin‐impregnated bednets give effective personal protection against transmission of W. bancrofti by An. gambiae, An. funestus and Cx quinquefasciatus in East Africa.
Visual and olfactory responses of haematophagous Diptera to host stimuli
Authors: Gibson G. , Torr S. J.
Published: March 2003

Key biotic and environmental constraints on the host‐orientated behaviour of haematophagous Diptera are summarized. For each major group of biting Diptera, responses to host stimuli are reviewed, including activation and ranging behaviour, long‐range and short‐range olfactory responses and visual responses. Limitations to the comparison of results between groups of species, and the practical problems of experimental method and equipment are discussed.
Expression of a functional antibody fragment in the gut of Rhodnius prolixus via transgenic bacterial symbiont Rhodococcus rhodnii
Authors: Durvasula R. V. , Gumbs A. , Panackal A. , Kruglov O. , Taneja J. , Kang A. S. , Cordon‐Rosales C. , Richards F. F. , Whitham R. G. , Beard C. B.
Published: March 2003

Expression within insects of foreign antiparasitic gene products via microbial symbionts could be used to prevent transmission of vector‐borne pathogens to vertebrate hosts. Genetically transformed symbiotic bacteria Rhodococcus rhodnii expressed functional antibody fragments (rDB3 encoding murine VH/K which binds progesterone) that were exported into the gut lumen of the triatomine bug Rhodnius prolixus (Hemiptera: Reduviidae), a vector of Chagas disease. Transgenic symbionts were maintained in successive nymphal instars and adults of Rhodnius prolixus despite competition with native untransformed Rhodococcus rhodnii. This is the first description of a functional mammalian antibody fragment expressed in an insect. Our system is a model for constructing paratransgenic insects (insects carrying transformed symbionts) with compromised ability to transmit pathogens.
The spatial distribution of larvae of Culicoides impunctatus biting midges
Authors: Blackwell A. , Lock K. A. , Marshall B. , Boag B. , Gordon S. C.
Published: March 2003

The spatial distribution of Culicoides impunctatus Goetghebuer (Diptera: Ceratopogonidae) larvae was sampled at a site in western Scotland, and geostatistical analyses were used to quantify spatial dependencies. Nested sampling and analysis indicated that most of the spatial variance occurred within distances of 160–640 cm, levelling off at distances > 640 cm. Semivariograms for transformed data from three 100 m × 100 m grids showed similar, isotropic patterns for larval counts, soil organic content, soil water content and the distribution of Juncus spp. rushes, with the variance increasing with separation distance. High levels of significance were associated with power models used to describe the semivariograms, which was indicative of the absence of a plateau (or ‘sill’) in the respective data. Correlation analysis of transformed data revealed significantly positive relationships between larval counts and soil pH, soil percentage organic content, soil percentage water content and also the distribution of Sphagnum spp., Juncus spp. and Myrica gale. There were also significantly negative relationships between larval counts and the distribution of Pteridium aquilinum and all mosses other than Sphagnum spp. The results suggest a far more structured and predictable pattern of C. impunctatus larval sites than previous studies and are discussed in relation to their application in localized Culicoides control and to studies of the mechanisms determining the spatial distribution of C. impunctatus larvae.
Isozyme evidence for three sibling species in the Anopheles sundaicus complex from Indonesia
Authors: Sukowati S. , Baimai V. , Harun S. , Dasuki Y. , Andris H. , Efriwati M.
Published: March 2003

Electrophoretic studies of isoenzymes in three chromosomally distinct forms (A, B and C) of the mosquito Anopheles sundaicus Theobald (Diptera: Culiciae) were undertaken on wild samples collected from six geographically isolated populations in Indonesia. Analyses of 12 enzyme systems comprising 15 loci revealed significant allelic variations, genetic polymorphism, within and among the populations of the An. sundaicus complex. Phylogenetic dendrograms produced by analysis using the Biosys‐1 program based on upgma methods show that all the populations of form A fall into one cluster, which is closely related to the form C cluster, whereas the populations of form B belong to a more distinct cluster. Allelic frequency and Wright’s F statistics of Mpi (mannose phosphate isomerase) are sufficient to identify individuals of each cytological form. This isozyme data correlates with our previous cytological evidence for the existence of three isomorphic species within the taxon An. sundaicus in Indonesia. These three species of the An. sundaicus complex were found together sympatrically at one locality, Asahan in North Sumatra.
Comparison of carbon dioxide‐baited trapping systems for sampling outdoor mosquito populations in Tanzania
Authors: Mboera L. E. G. , Knols B. G. J. , Braks M. A. H. , Takken W.
Published: March 2003

For collecting mosquitoes (Diptera: Culicidae) the outdoor catching efficiency of four types of trapping devices baited with carbon dioxide (CO2, 300 ml/min) was evaluated and compared in two areas of Tanzania. The types of traps employed were: the CDC miniature trap with the incandescent light bulb switched on or off; electric nets (ENT) and a Counterflow Geometry (CFG) trap. In Njage, south‐east Tanzania, Anopheles gambiae Giles sensu stricto was the most abundant of the seven mosquito species obtained, comprising of 74.3% of the total number caught (n = 2171). In Muheza, north‐east Tanzania, Culex quinquefasciatus Say was the predominant species (90.9%) among 1080 caught. At both localities the CFG trap was superior to the CDC trap with light‐on or light‐off for sampling both An. gambiae and Cx. quinquefasciatus. Efficiency of the CFG trap and ENT were similar for sampling these species of mosquitoes (P > 0.05). However, ENT was superior to the CDC trap with light‐off for collecting both species. Significantly more (P < 0.05) Cx. quinquefasciatus were obtained by the CDC trap with light‐off than with light‐on, especially outdoors. It is concluded that both ENT and the CFG are effective tools for sampling populations of An. gambiae and Cx. quinquefasciatus outdoors.
Salivary proteins and glycoproteins in phlebotomine sandflies of various species, sex and age
Authors: Volf P. , Tesařová P. , Nohýnkova E.
Published: March 2003

Salivary gland proteins were studied in sandflies (Diptera: Psychodidae: Phlebotominae) by electrophoretic techniques. In Phlebotomus duboscqi Neveu‐Lemaire the protein concentration was about 30 times higher in females than in males. SDS PAGE revealed eight major bands of 29–62 kDa in salivary gland extracts (SGE) from females, whereas only one band of 57 kDa was detected in males. The number of protein components in SGE gradually increased with the age of females. In P. papatasi (Scopoli) the typical electrophoretic pattern was reached in 3–5 days after imago emergence, depending on the temperature at which females were maintained. All major protein components of the female SGE were present in the content of glands. Female SGE were compared in seven colonies of five Phlebotomus and Lutzomyia species; electrophoretic profiles distinguished between species and even between colonies of different geographical origin. In general, the highest variability of major protein components was observed in the 38–48 kDa region. Four colonies of the subgenus Phlebotomus (P. duboscqi and P. papatasi) possessed common mobility polypeptides, the highest similarity was found between two colonies of P. papatasi. Other species tested significantly differed, specific prominent bands of 33, 35 and 38 kDa were found in P. halepensis Theodor, P. perniciosus Newstead and Lutzomyia longipalpis (Lutz & Neiva), respectively. Glycoproteins in SGE of Lu. longipalpis and P. duboscqi females were identified and analysed using blotting with five lectin conjugates. Specific reaction of lectins ConA and WGA revealed the complex type of N‐glycans in the 48 and 53–54 kDa glycoproteins present in both species. Similar glycosylation was detected in species‐specific bands of the 57–60 and 65–67 kDa in P. duboscqi and Lu. longipalpis, respectively. The high mannose type of glycosylation was found in the 20 and 39 kDa polypeptides of Lu. longipalpis and the 40–42 kDa polypeptides of P. duboscqi. Innate lectin activity specific for aminosugars was detected in SGE of P. duboscqi females using haemagglutination tests with rabbit erythrocytes.
Interactions between cattle and biting flies: effects on the feeding rate of tsetse
Authors: Torr S. J. , Mangwiro T. N. C.
Published: March 2003

In Zimbabwe, studies were made of the effect of host behaviour on the feeding success ofGlossina pallidipesAusten andG. morsitans morsitansWestwood (Diptera: Glossinidae) attracted to cattle of different age and sex. The mean feeding rates for male and femaleG. pallidipesattracted to oxen were 60% and 58%, respectively, compared to 33% and 53% for male and femaleG. m. morsitans. The feeding rate ofG. pallidipesvaried between oxen and was inversely correlated with a host's rate of defensive leg movements, which, in turn, was positively correlated with the density ofStomoxysspp. (Diptera: Muscidae) caught in the vicinity of the host. Tsetse were significantly less successful in feeding from young cattle. ForG. pallidipes, the feeding rate on calves (< 6 months) was 11%, whereas for male and femaleG. m. morsitansthe rates were 12% and 20%, respectively. Significantly lower feeding rates were apparent for cattle aged up to 2 years, when the feeding rate forG. pallidipes(31%) was still significantly less than that on mature oxen (68%). Feeding rates forG. pallidipeson adult female cattle were lower than those on oxen (45% vs. 61%). The lower feeding rates in young animals were attributed to higher rates of defensive movements. The results suggest that higher rates of defensive activities by young cattle reduce the risk of them contracting trypanosomiasis.