bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantitative monitoring of serum hepatitis B virus DNA and blood lymphocyte subsets during combined prednisolone and interferon‐α therapy in patients with chronic hepatitis B
Authors: Fei G. ‐Z. , Sylvan S. P. E. , Yao G. ‐B. , Hellström U. B.
Published: March 2003

Several investigators have reported a significantly reduced CD4/CD8 ratio, as defined by monoclonal antibodies, in the peripheral blood of Caucasian patients with chronic active hepatitis B (CAHB). In Asian patients with chronic hepatitis B, quantitative analyses of subpopulations of peripheral blood lymphocytes have not been able to confirm these findings. In this work, we analysed the frequency of peripheral blood lymphocyte subsets in 10 Chinese patients with histologically proven CAHB and seven healthy Chinese individuals. Four of the 10 CAHB patients received combined prednisolone/interferon‐α2b (IFN‐α2b) therapy. Peripheral blood samples were consecutively collected for analysis of lymphocyte subpopulations using an indirect immunofluorescence (IF) method, and hepatitis B virus (HBV) DNA was quantified by a chemiluminescent, molecular‐hybridization assay. Peripheral blood mononuclear cells from seven Chinese control individuals comprised 63 ± 3% CD3+ cells, of which 41 ± 4% were of CD4+ and 23 ± 2% of CD8+ subsets. The mean CD4/CD8 ratio in the healthy controls was 1.9 (95% confidence interval = 1.1–2.7). The CD4/CD8 ratios were significantly reduced (P < 0.01) in the 10 patients with chronic hepatitis B, compared with those of the controls, owing to a significant increase in the number of CD8+ cells (P < 0.005). During the treatment with prednisolone, a significant increase in the CD4/CD8 ratio was observed in all treated patients. This increase was mainly caused by a decrease in the number of CD8+ cells and was accompanied by an increase in serum HBV DNA levels, which peaked during the latter part of the prednisolone cycle. During the treatment with IFN‐α2b, a second increase in the CD4/CD8 ratio was observed, which was caused by an increase in CD4+ cells. A marked decrease in viral load was observed, during treatment with IFN‐α2b, in patients with HBV DNA levels below 10 000 pg ml–1. Our data indicate that the CD4/CD8 ratios in Chinese CAHB patients do not differ from those of Caucasian patients with CAHB, when analysed using similar methods for the enumeration of lymphocyte subsets. Profound effects on cellular distribution and viral replication were noted during the combined prednisolone/IFN‐α2b therapy. Additional studies of the modulatory effect of the combined therapy on the distribution of lymphocyte subsets and cytokine profiles in relation to the therapeutic outcome of HBV infection are warranted.
Prevalence of hepatitis viruses in an anti‐human immunodeficiency virus‐positive population from Argentina. Amulticentre study
Authors: Fainboim H. , GonzÃ¡lez J. , Fassio E. , MartÂ´ınez A. , Otegui L. , Eposto M. , Cahn P. , Marino R. , Landeira G. , Suaya G. , Gancedo E. , Castro R. , Brajterman L. , LaplumÃ© H.
Published: March 2003

The objectives of this study were to investigate the prevalence of infections with hepatotrophic viruses in an anti‐human immunodeficiency virus (HIV)‐positive population from Buenos Aires and to compare it among the main risk groups for HIV infection. Four hundred and eighty‐four consecutive patients attending the HIV outpatients clinic were studied: 359 men and 125 women, median age 29 years (range 16–67 years); 35.5% had presented acquired immune deficiency syndrome (AIDS)‐defining conditions. Two hundred and thirty‐four patients were intravenous drug users (IVDU), 99 had homosexual and 142 heterosexual preference, seven had received blood transfusions and two had no risk factors. Hepatitis B surface antigen (HBsAg), and antibodies to hepatitis B core antigen (HBcAb) and to hepatitis C virus (anti‐HCV) were investigated in all patients; antibodies to HBsAg (HBsAb) and IgG antibodies to hepatitis D virus (anti‐HDV) in all HBcAb‐positive patients; hepatitis B e antigen and antibodies to HBeAg (HBeAg) in all HBsAg‐positive patients; IgG antibodies to hepatitis A virus (anti‐HAV) in the first 307 patients; and IgG antibodies to hepatitis E virus (anti‐HEV) in the first 91 patients. As control groups, contemporary voluntary blood donors were studied for prevalence of HAV, HBV, HCV and HEV. The percentages of HBcAb, HBsAg, anti‐HCV and anti‐HEV (58.5, 14.5, 58.5 and 6.6%, respectively) were significantly higher in anti‐HIV‐positive patients than in control groups (3.2, 0.5, 1.0 and 1.8%, respectively) (P=0.000). The prevalence of HBcAb was significantly higher
in IVDU (72.6%) than in heterosexuals (33.8%) (P=0.0001)
and in homosexuals (59.6%) (P=0.0189). The percentage of HBsAg was
significantly higher in IVDU (19.2%) than in heterosexuals (6.3%)
(P=0.0004). Anti‐HCV was significantly higher in IVDU (92.3%) than
in homosexuals (14.1%) and in heterosexuals (33.1%) (P=0.000 in both cases). The prevalence of anti‐HDV was relatively low (1.9%). There was no difference in the percentage of anti‐HAV between HIV‐positive and negative subjects. In conclusion, there is a high prevalence of HBV and HCV infections in HIV‐positive patients from our area. Drug use is the main route of transmission, but prevalence of HCV in patients with, probably, sexually acquired HIV infection is also higher than in the control group. The increased prevalence of HEV infection in HIV‐positive individuals is another provocative finding that warrants further study.
Lamivudine, adefovir and tenofovir exhibit long‐lasting anti‐hepatitis B virus activity in cell culture
Authors: Ying  , De Clercq  , Neyts
Published: March 2003

In this work, we investigated the anti‐hepatitis B virus (HBV) activity of lamivudine, adefovir, tenofovir, penciclovir and lobucavir after short‐term (i.e. 24 or 48 h) or continuous (9 days) exposure of the HBV‐containing cell line, HepG2 2.2.15, to these drugs. Lamivudine maintained significant anti‐HBV activity when added for only 24 or 48 h to the cell cultures compared to when the drug was present for the whole period (9 days) on the cells, i.e. 50% effective concentration (EC50) values for the inhibition of HBV DNA synthesis were 0.07 ± 0.02 μg ml−1 after 24 h of incubation, 0.02 ± 0.01 μg ml−1 after 48 h of incubation and 0.0016 ± 0.001 μg ml−1 after 9 days of incubation. Similarly, the nucleoside phosphonate analogues, adefovir and tenofovir, retained significant anti‐HBV activity when added for only a short period of time to the cells. The EC50 values were 12 ± 1 μg ml−1 (24 h) and 1.0 ± 0.2 μg ml−1 (48 h) vs 0.003 ± 0.001 μg ml−1 (9 days) for adefovir, and 6.5 ± 1.1 μg ml−1 (24 h) and 0.8 ± 0.1 μg ml−1 (48 h) vs 0.03 ± 0.02 μg ml−1 (9 days) for tenofovir. In contrast, penciclovir and lobucavir lost most of their anti‐viral activity when present on the cells for 48 h or less.
Interferon plus ribavirin in chronic hepatitis C non‐responders to recombinant α‐interferon
Authors: Bresci  , Parisi  , Bertoni  , Scatena  , Capria
Published: March 2003

The aim of this study was to evaluate the most appropriate therapeutic protocol for patients with chronic hepatitis C not responding to a previous course of recombinant interferon α‐2b (rIFN). Sixty patients were randomly assigned to two groups of 30 subjects each: group A was treated with double dose of the same type of rIFN (6 MU t.i.w.) plus ribavirin for 6 months; group B was treated with the same rIFN dose and duration as group A, but without ribavirin. An end of treatment complete response (ETCR) was defined as alanine transaminase (ALT) normalization with undetectable serum HCV‐RNA at the end of the treatment, while an end of treatment biochemical response (ETBR) as ALT normalization with still detectable viraemia. The two groups were homogeneous. The patients with ETCR or ETBR were than followed‐up for at least 1 year. A sustained biochemical response (SBR) was defined as the persistence of normal ALT with still detectable viraemia after a 12‐month follow‐up, and a sustained complete response (SCR) as the persistence of normal ALT with undetectable viraemia. Side‐effects were only observed in patients treated with rIFN plus ribavirin: four cases (13%) discontinued the therapy owing to haemolytic anaemia. Combination therapy induced an ETCR in 11 patients (37%) and an ETBR in six (20%), while a SCR was observed in two subjects (7%) and a SBR in four (13%). The use of a double dose of rIFN alone obtained an ETCR in four cases (13%) and an ETBR in five (17%), with a SCR in two (7%) and a SBR in three (10%). Hence, both combination therapy and single treatment with higher rIFN doses were unable to show statistically significant long‐term benefits in patients with chronic hepatitis C resistant to a previous course of rIFN treatment.
Sensitivity and specificity of third‐generation hepatitis C virus antibody detection assays: an analysis of the literature
Authors: Colin C. , Lanoir D. , Touzet S. , Meyaud‐Kraemer L. , Bailly F. , Trepo C. ,   the HEPATIS Group
Published: March 2003

This study assessed the sensitivity and specificity of third‐generation serological hepatitis C diagnostic tests from an analysis of the literature. The literature analysis was run using criteria from McMaster University for the assessment of diagnostic tests. The selected studies were grouped according to the type of population at high and low risk for hepatitis C virus (HCV) infection and to the type of reference test. The homogeneity of the sensitivity and the specificity was tested in each group using a Fisher’s exact test. Of 132 studies, 10 were selected. When the estimates were homogeneous, summary point estimates and confidence intervals were computed; when the estimates were heterogeneous, subgroup analysis was performed.

The sensitivity of third‐generation enzyme‐linked immunosorbent assay (ELISA3) was estimated at 98.9% (95% CI: 94–100%) in patients with chronic liver disease and at 97.2% (95% CI: 92–99%) in panels of sera. ELISA3 specificity was found at 100% in patients with chronic liver disease. The sensitivity of the third generation recombinant immunoblot assay (RIBA3) was assessed at 78.8% (95% CI: 65–89%) in haemodialysed patients.

This analysis provides evidence for the good sensitivity and specificity of ELISA3 assays particularly in high risk patient groups and confirms their use for screening in these populations. Further studies are needed to assess properly RIBA3 in general population and in risk patients.
Effect of HLA class II genotype on T helper lymphocyte responses and viral control in hepatitis C virus infection
Authors: Harcourt G. , Hellier S. , Bunce M. , Satsangi J. , Collier J. , Chapman R. , Phillips R. , Klenerman P.
Published: March 2003

Hepatitis C virus (HCV) infection is very common worldwide, but has a broad range of outcomes. A minority of patients are able to clear infection spontaneously, and this is thought to be due to the emergence and maintenance of effective cell‐mediated immunity, particularly CD4+ T lymphocyte responses. Furthermore, genetic studies have indicated that HLA class II genotype strongly influences the outcome of infection. We have therefore investigated the influence of the protective HLA class II haplotype (DQB1*0301, which is in tight linkage disequilibrium with DRB1*1101) on the CD4+ T lymphocyte responses to HCV. We observe a strong association between this genotype and maintenance of a multispecific CD4+ T helper response. The effect on T helper responses was also maintained after combination interferon‐α/ribavirin therapy, although the latter influenced the pattern of viral antigens to which patients responded. This is the first disease in which an association of HLA genotype with clinical outcome has been linked to an alteration of the immunological phenotype. The selection of protective peptides in those with the favourable HLA class II genotype may point in the direction of suitable vaccine candidates.
Virological response to interferon therapy of chronic hepatitis B as measured by a highly sensitive assay
Authors: Lindh M. , Hannoun C. , Horal P. , Krogsgaard K. ,   the INTERPRED Study Group
Published: March 2003

In the interferon (IFN) treatment of chronic hepatitis B, there is no accepted definition of virological response as measured by highly sensitive HBV DNA assays. In the present study of 98 patients given IFN (10 MU/day for 1 week, then 10 MU TIW for 11 weeks) with or without prednisolone priming, a virological response was identified as log HBV DNA/mL below 6.0 (by Amplicor Monitor, Roche) 6 months post‐treatment. At this time, 92% (33/36) of the sustained responders (SR) still had detectable viraemia with log HBV DNA/mL at 4.30 ± 0.15 (± SEM), as compared with 8.69 ± 0.097 in nonsustained responders. Pretreatment viraemia below a threshold at 500 million copies/mL was associated with higher chance of response (P=0.023). Prednisolone enhanced the sustained response (53% vs. 30%, P=0.025), and in particular end‐of‐treatment response (ETR, 50% vs. 10%, P < 0.0001). ETR was predictive for SR (P < 0.0001), especially when log HBV DNA/mL was < 4.0 (PPV=92%). The potential value of differentiating the therapy of chronic hepatitis B on the basis of viraemia levels, as measured by highly sensitive assays, should be further investigated.
Enhanced antiviral effect in cell culture of type 1 interferon and ribozymes targeting HCV RNA
Authors: Macejak D. G. , Jensen K. L. , Pavco P. A. , Phipps K. M. , Heinz B. A. , Colacino J. M. , Blatt L. M.
Published: March 2003

We have recently shown that the replication of an HCV‐poliovirus (PV) chimera that is dependent upon the hepatitis C virus (HCV) 5′ untranslated region (UTR) can be inhibited by treatment with ribozymes targeting HCV RNA. To determine the antiviral effects of anti‐HCV ribozyme treatment in combination with type 1 interferon (IFN), we analysed the replication of this HCV‐PV chimera in HeLa cells treated with anti‐HCV ribozyme and/or IFN‐α2a, IFN‐α2b, or consensus IFN. The anti‐HCV ribozyme, or any of the IFNs alone have significant inhibitory effects on HCV‐PV replication compared to control treatment (≥ 85%, P < 0.01). The maximal inhibition due to IFN treatment (94%, P < 0.01) was achieved with ≥ 50 U/ml for either IFN‐α2a or IFN‐α2b compared to control treatment. A similar level of inhibition in viral replication could be achieved with a 5‐fold lower dose of IFN if ribozyme targeting the HCV 5′ UTR was given in combination. For consensus IFN, the dose could be reduced by > 12.5‐fold if ribozyme targeting the HCV 5′ UTR was given in combination. Conversely, the dose of ribozyme could be reduced 3‐fold if given in combination with any of the IFN preparations. Moreover, treatment with low doses (1–25 U/mL) of IFN‐α2a, IFN‐α2b, or consensus IFN in combination with anti‐HCV ribozyme resulted in > 98% inhibition of HCV‐PV replication compared to control treatment (P < 0.01). These results demonstrate that IFN and ribozyme each have a beneficial antiviral effect that is augmented when given in combination.
Effect of virological response on post‐treatment durability of lamivudine‐induced HBeAg seroconversion
Authors: Lee K. M. , Cho S. W. , Kim S. W. , Kim H. J. , Hahm K. B. , Kim J. H.
Published: March 2003

Lamivudine‐induced HBeAg seroconversion may not be durable in Korean patients with hepatitis B virus (HBV) infection. It is unknown whether virological response during lamivudine treatment affects the post‐treatment outcome. We retrospectively analysed 124 consecutive HBeAg‐positive chronic hepatitis B (CHB) patients treated with lamivudine. Lamivudine was given at a dose of 100 mg per day. HBV DNA levels in sera obtained before and during therapy were measured by the Digene Hybrid Capture II assay and Digene Ultrasensitive Hybrid Capture II assay, respectively. HBeAg seroconversion was achieved in 42 of the 124 patients (33.8%) treated with lamivudine. Mean duration of treatment in HBeAg seroconverters was 12.86 ± 4.44 months. During the follow‐up period, the cumulative relapse rates at 3 months and 6 months post‐treatment in 42 patients with HBeAg seroconversion were 40.5% and 57.4%, respectively. Among 31 seroconverted patients whose sera were available at the second month of treatment, HBV DNA remained at > 4.7 × 103 genomes/mL in 15 patients and decreased to < 4.7 × 103 genomes/mL in the remaining 16 patients. HBV DNA levels at the second month of treatment was not related with relapse after discontinuation of treatment (66.7% vs. 43.8%, P= 0.2). At the time of HBeAg seroconversion, HBV DNA remained at > 4.7 × 103 genomes/mL in five patients and decreased to < 4.7 × 103 genomes/mL in the remaining 37 patients. Relapse rates were increased in patients who remained at > 4.7 × 103 genomes/mL compared with patients with HBV DNA levels < 4.7 × 103 genomes/mL (100% vs. 51.4%, P < 0.001). Thus, monitoring of serum HBV DNA at the time of HBeAg seroconversion may be helpful for predicting relapse in patients with lamivudine‐induced HBeAg seroconversion.
Regulatory elements of hepatitis B virus transcription
Authors: Moolla Naazneen , Kew Michael , Arbuthnot Patrick
Published: March 2003

summary. The precise modulation of hepatitis B virus (HBV) gene expression is essential for replication of the virus. HBV sequences are transcribed under the control of the preC/pregenomic, S1, S2 and X promoters. With the exception of S1, all the HBV promoters lack the orthodox TATA box motifs required for the formation of the transcription initiation complex, and as such they represent a unique model of transcription initiation elements. The presence of two enhancer sequences and negative regulatoryelements in the HBV genome further augments thecontrolled synthesis of HBV‐ RNA. All these transcription cis‐elements are embedded within protein coding regions of the genome. This feature demonstrates the remarkable ability of the virus to maximize the function of its small genome. HBV transcription control elements also display a preference for liver‐specific or liver‐enriched trans‐factors, which contributes to the liver tropism of the virus. This review outlines the major HBV transcription regulatory elements and highlights the reliance of accurate HBV gene modulation on the complex interplay between several trans‐acting factors and their corresponding cis‐ motifs in the viral genome.
Targeted destruction of the polymerized human serum albumin binding site within the preS2 region of the HBV surface antigen while retaining full immunogenicity for this epitope
Authors: Park J.‐H. , Lee M.‐K. , Kim H.‐S. , Kim K. L. , Cho E.‐W.
Published: March 2003

summary.The 55‐amino acid (a.a.) preS2 region of the hepatitis B virus (HBV) envelope protein is highly immunogenic, and antibodies against this epitope confer seroprotection against HBV infections. Accordingly, various experimental and clinical studies for developing and evaluating HBV vaccines that include this particular epitope have been reported. However, a pitfall in using preS2 epitopes as part of a vaccinating antigen is that polymerized human serum albumin (pHSA), which is a normal constituent of the human serum, binds to and makes complexes with this particular region. Consequently, it is most likely that the antigen epitope is masked by serum pHSA and subsequently not detected by the immune system. To overcome these limitations, a novel single a.a substitute of the preS2 region was designed that corresponds to a tyrosine to serine exchange at position 140 of preS2. Competitive enzyme‐linked immunosorbent assay showed that this substitution completely abolishes pHSA‐binding activities in the mutated preS2 peptide, and CD spectra analysis revealed that this property might have been induced by slight conformational changes in its secondary structure. Nevertheless, the original B‐cell epitope was still preserved in the mutated preS2 as determined by experimental immunization in mice. In this regard, the preS2(120–145/Y140S) sequence may be an HBV vaccine where epitopes, with intrinsic properties have been deleted without affecting the immunogenicity of the epitope itself. It is expected that the inclusion of this point mutated preS2 epitope will improve the efficacy of conventional preS2‐containing HBV vaccines.
The impact of prior hepatitis B virus infection on liver histology and the response to interferon therapy in chronic hepatitis C
Authors: Myers R. P. , Thibault V. , Poynard T.
Published: March 2003

summary.  Patients with chronic hepatitis C frequently have antibodies to the hepatitis B core antigen (anti‐HBc), indicative of prior hepatitis B virus (HBV) infection. In these patients, persistence of HBV may exacerbate liver injury and diminish the response to treatment. The aim of this study was to evaluate the relationship between previous HBV infection and liver histology and the sustained virologic response (SVR) to interferon (IFN)‐based therapy in patients with chronic hepatitis C. A total of 132 HBsAg‐negative, treatment‐naive patients were evaluated. Using multiple logistic regression analysis, the impact of anti‐HBc‐positivity on the rate of SVR was determined. Progression to bridging fibrosis or cirrhosis was assessed using Cox proportional hazards regression and Kaplan–Meier survival analysis. The median age of the patients was 47 years (IQR, 37–60), 57% were male, and 73% had genotypes 1, 4, 5, or 6. Fifty‐one patients (39%) were anti‐HBc‐positive. The prevalence of moderate to severe necroinflammatory activity (P = 0.36) and progression to bridging fibrosis or cirrhosis (log‐rank P = 0.83) was similar between anti‐HBc‐positive and ‐negative patients. After a median of 48 weeks (IQR, 26–52) of therapy (IFN, n = 116; IFN and ribavirin, n = 16), 23 patients (17%) achieved a SVR; the rate of response was similar in anti‐HBc‐positive and ‐negative patients (18%vs 17%, P = 1.00). After controlling for age, gender, genotype, fibrosis, and treatment regimen, anti‐HBc status did not independently affect the rate of SVR (anti‐HBc‐positive vs negative: odds ratio, 1.36; 95% confidence interval, 0.45 to 4.06; P = 0.58). In conclusion, previous HBV infection does not affect liver histology or the response to IFN‐based therapy in patients with chronic hepatitis C.
Time on antiretroviral therapy is a protective factor for liver fibrosis in HIV and hepatitis C virus (HCV) co‐infected patients
Authors: Tural C. , Fuster D. , Tor J. , Ojanguren I. , Sirera G. , Ballesteros À. , Lasanta J. A. J. , Planas R. , Rey‐Joly C. , Clotet B.
Published: March 2003

summary. To assess the factors associated with liver fibrosis in human immunodeficiency virus and hepatitis C virus (HIV/HCV) co‐infected patients eligible for anti‐HCV therapy, we performed an observational, single‐centred, cross‐sectional study of 180 HIV/HCV co‐infected patients who underwent liver biopsy between May 1998 and November 2001. A total of 126 patients with a known date of HCV infection were evaluated. Liver fibrosis was defined as a Knodell stage of fibrosis 1–4. The mean age was 36.7 (3.8) years, 81% were male and had a mean age of 20.5 (3.8) years at HCV infection. Mean CD4 cell count and plasma HIV‐1 RNA load at the time of biopsy were 552 cell/mm3 (239) and 2.5 log10 (0.9), respectively; 118 patients had been on antiretroviral therapy (ART) for a median of 45 months (Q1–Q3: 21–75) and 84 on protease inhibitor for a median of 12.0 months (Q1–Q3: 0–29.5); 55 had an AIDS event or a CD4 cell count nadir < 200 cells/mm3 prior to biopsy. Median histological activity index was 6 and 27% had a Knodell stage of fibrosis 0. On the multivariate analysis time on ART (OR for 6 months extra: 0.954, 95% CI: 0.859–0.994), CD4 cell count at the time of liver biopsy (OR for 100 cells/mL increase: 0.740, 95% CI: 0.670–0.905), age at HCV infection acquisition (OR for 5 years extra: 2.594, 95% CI: 1.326–5.133) and alcohol intake (> 50 g/day) (OR: 2.73, 95% CI: 1.108–6.731) were associated with liver fibrosis. Hence ART should be a priority in HIV/HCV co‐infected patients eligible for anti‐HCV treatment as it is a protective factor for liver fibrosis.
An assessment of British farmers’ and gamekeepers’ experiences, attitudes and practices in relation to the European Polecat Mustela putorius
Authors: Packer James J. , Birks Johnny D. S.
Published: March 2003

Postal questionnaires were distributed to farmers and gamekeepers within the Polecat’s Mustela putorius main range in Britain. Only 11% of responding farmers had ever experienced damage by Polecats; 28% regarded the species as a threat to livestock. Conversely 53% of farmers believed Polecats control Rabbits Oryctolagus cuniculus, and 39% believed they control rodents on the farm. Two‐thirds of responding gamekeepers had experienced Polecat predation of penned game, with the commonest access routes via ‘pop‐holes’ and beneath the perimeter wire. Most gamekeepers (68%) regarded the Polecat as a minor pest, but ranked it as a less serious threat to game than predators such as the Fox Vulpes vulpes, Feral Cat Felis catus, Stoat Mustela erminea, corvids and Mink Mustela vison.

Majorities of both farmers and gamekeepers would be concerned about an increase in the numbers of Polecats, and most wished to be free to control the species. Trapping was regarded as the main defence against Polecat predation of game; 91% of gamekeepers had trapped Polecats over the preceding 5 years. A minority of farmers carried out Polecat control; this activity was more prevalent on farms near the fringe of the species’ range. Pest‐control practices likely to impact accidentally or indirectly upon Polecats, such as rodenticide use, fumigation (‘gassing’) of Rabbit burrows and ferreting, were also more prevalent on farms towards the fringe of the species’ range.

These findings are discussed in the light of the Polecat’s status as a Scheduled species recovering its range in Britain. In anticipation of the species’ further spread into areas where game shooting is prevalent, recommendations are made regarding the need to improve game husbandry and to modify trapping practice. In particular, the night‐time closure of pop‐holes and the effective exclusion of Polecats from tunnel traps are suggested as a means of promoting greater tolerance of Polecats and compliance with the law.
Review of the distribution ofMesoplodonspecies (order Cetacea, family Ziphiidae) in the North Atlantic
Authors: Macleod Colin D.
Published: March 2003

Four species of beaked whales of the genusMesoplodonregularly occur in the North Atlantic. These are Sowerby's Beaked WhaleMesoplodon bidens, Blainville's Beaked WhaleMesoplodon densirostris, Gervais Beaked WhaleMesoplodon europaeus andTrue's Beaked WhaleMesoplodon mirus. These four species differ in their distribution within this area.M. bidensis the most northerly recorded species followed byM. mirus.M. densirostris and M. europaeusboth generally occur further south and their distributions cross the equator. The distribution ofMesoplodonspecies may relate to variations in water temperature.
A reassessment of the distribution of the rareGenetta johnstoni(Viverridae, Carnivora) with some newly discovered specimens
Authors: GAUBERT P. , VERON G. , COLYN M. , DUNHAM A. , SHULTZ S. , TRANIER M.
Published: March 2003

The rare Johnston’s Genet (Genetta johnstoni) is one of the least known small carnivores inhabiting the West African rain forest. Some newly discovered specimens collected from the field (Guinea and Ivory Coast) and several rediscovered specimens resulting from reinvestigating collections, have permitted us to reconsider the distribution of the species. Coupled with a bibliographic review and a census of specimens kept in public collections, a reassessed distribution map is proposed, extending the previous estimated range 400 km to the West (Kolenté Plates, Guinea) and more than 600 km to the East (Tarkwa, Ghana). The majority of collected specimens have come from the inland forests of northern Liberia and south‐eastern Guinea, while the surroundings of Mt. Nimba also support numbers of this species. We suggest that the supposed restriction ofG. johnstonito rain forest be re‐evaluated because a specimen was collected in a region of moist woodlands and savannah (Kolenté Plateau). With regard to these new distributional data, conservation implications for the whole Upper Guinean block population are discussed.
Isolation of the spirochaete Borrelia afzelii from the mosquito Aedes vexans in the Czech Republic
Authors: HALOUZKA  , POSTIC  , HUBÁLEK
Published: March 2003

During the years 1993–1995, a total of 3580 culicine mosquitoes of six species were collected in South Moravia, Czech Republic, and examined by dark‐field microscopy for the presence of borreliae. Females of Aedes cantans, Ae. sticticus, Ae. vexans, Culex pipiens and Cx pipiens biotype molestus (but not Ae. geniculatus or Culiseta annulata) harboured spirochaetes, the frequencies ranging from 0.7% to 7.8%. One isolate (BR‐53) from Ae. vexans was identified as Borrelia afzelii genospecies. The potential role of mosquitoes in the epidemiology of Lyme borreliosis should be investigated.
GranulocyticEhrlichiainfection in Ixodid ticks and mammals in woodlands and uplands of the U.K.
Authors: Ogden N. H. , Bown K. , Horrocks B. K. , Woldehiwet Z. , Bennett M.
Published: March 2003

Abstract.The prevalence of infection with Ehrlichiae of the Ehrlichia phagocytophila genogroup (the granulocytic Ehrlichiae), in questing Ixodes ricinus ticks of U.K. upland and woodland habitats, was investigated by PCR. The prevalence of infection in the three feeding stages of I. ricinus indicated that granulocytic Ehrlichiae are transmitted transstadially with no, or inefficient, transovarial transmission. The presence of infected ticks in both habitats indicates that endemic cycles of granulocytic Ehrlichia (GE) infection are maintained by both domesticated sheep and by wild reservoirs, and coexist with endemic cycles of Borrelia burgdorferi infection. Moreover, demonstration, for the first time, of GE infection in engorged Ixodes trianguliceps ticks and blood collected from wild rodents, suggests that European wild rodents are competent reservoirs. GE infection prevalence in nymphal and adult I. ricinus was significantly greater in uplands than woodlands, which is consistent with ticks of all three feeding stages feeding on reservoir‐competent sheep in uplands. In one woodland studied, pheasants are important hosts for nymphal I. ricinus but are incompetent or inefficient reservoirs, so reducing GE infection prevalence in I. ricinus ticks in this habitat. 16S rRNA sequences of GE from ticks of these U.K. habitats, showed a high degree of homology with those of granulocytic Ehrlichiae isolated from humans, but also showed some evidence of genetic diversity of granulocytic ehrlichiae in the U.K. The implications of these findings, for the taxonomy of granulocytic ehrlichiae and the potential for human infections to occur in the U.K., is discussed.
Metaphase karyotypes and G‐banding in sandflies of the Lutzomyia longipalpis complex
Authors: Yin Huaizhi , Mutebi J. ‐P. , Marriott S. , Lanzaro G. C.
Published: March 2003

Abstract. Mitotic metaphase chromosomes (2n = 8) from brain cells of fourth instar sandfly larvae of four geographical strains of the Lutzomyia longipaplis complex were examined microscopically, with bright‐field illumination, after staining by a new G‐banding technique involving exposure of air‐dried chromosome preparations to quinacrine and ultraviolet light. Differences of G‐banding and/or position of the centromere on chromosome 4 (the smallest chromosome pair) distinguished four putative sibling species from Costa Rica, Colombia and Brazil (distinctive populations from Jacobina and Lapinha Caves). The karyotype of the population from Jacobina, Brazil, showed an apparently plesiomorphic pattern of G‐banding. On the basis of their recognizably different mitotic karyotypes, cytogenetic identification of separate taxa in the L. longipalpis complex should be useful for specific female vector competence and ecology studies.
Mixed infection by tick‐borne encephalitis virus and Borrelia in ticks
Authors: Korenberg E. I. , Kovalevskii Y. V. , Karavanov A. S. , Moskvitina G. G.
Published: March 2003

To investigate the relationships between tick‐borne encephalitis (TBE) virus and the bacterial spirochaete Borrelia burgdorferi sensu lato in vectors with mixed infections, unfed adult Ixodes persulcatus ticks were collected by flagging from vegetation in southern‐taiga forests of the Pre‐Urals region of Russia where both infections circulate sympatrically. Prevalences of TBE and Borrelia infections in a total of 4234 ticks were compared over 5 years. No significant differences were revealed between the prevalence of Borrelia infection in ticks with and without TBE virus (29.4 ± 7.8% vs 23 ± 3.6%), or between the prevalence of TBE virus infection in ticks with and without Borrelia (24.0 ± 6.6% vs 18.4 ± 3.4%). In ticks with mixed infection (40/689 = 5.8%), concentrations of TBE virus and Borrelia were not significantly correlated with one another. Field observations showed parallel trends in the prevalence of these pathogens in tick populations from year to year (1993–1997) indicating that, in I. persulcatus with mixed infection, Borrelia and TBE virus do not seem to interfere with each other and are apparently not involved in any antagonistic relationships.
Sugars in the gut of the sandfly Phlebotomus orientalis from Dinder National Park, Eastern Sudan
Authors: Hamilton J. G. C. , Naiem D. A. E.L.
Published: March 2003

The sandfly Phlebotomus orientalis Parrot (Diptera: Psychodidae) is the vector of visceral leishmaniasis in eastern and Upper Nile regions of Sudan, where vector infection rates of over 7% have been reported. Sugars are known to be important for development of the parasite and for increasing the survival and oviposition rates of several species of sandflies.

In the present study we have analysed the sugars present in the guts of individuals and groups of male and female P. orientalis and compared these with sugars from several potential local plant sources: Acacia seyal, Balanites aegyptiaca and Combretum kordofanum. The distribution of these trees in Sudan is closely correlated with that of P. orientalis.

Only 20% of individually analysed female sandflies had significant amounts of sugars present suggesting that P. orientalis either digest their sugar meal quickly or do not require regular sugar meals. Interestingly, the sugars present in the males were significantly different to those found in the females, indicating that they had fed on different sugar sources.

There was evidence that fruit sugars from Balanites aegyptiaca, Combretum kordofanum and aphid or coccid honeydew are utilized by male and female P. orientalis. There was evidence to indicate that female P. orientalis feeds directly on honeydew. There was no evidence to indicate that direct feeding on leaves is a typical source for the sugar meal. There was no melizitose and only a very small amount of turanose present in the male, suggesting that honeydew was not an important sugar source for males.
Cleptohaematophagy of the Triatomine bug Belminus herreri
Authors: Sandoval C. M. , Joya M. I. , Gutierez R. , Angulo V. M.
Published: March 2003

The Triatomine bug Belminus herreri, previously known only from Panama, is reported for the first time from Colombia. Three adult B. herreri were collected from a chicken coop and a viable egg was found on a Bactris palm at Carmen municipality in humid forest zone at 680 m altitude. From 44 eggs produced, five progeny were reared to adulthood. During early instars they were unable to take bloodmeals directly from vertebrate hosts, but they fed successfully by cleptohaematophagy on blood from replete Rhodnius prolixus.
Further evidence that deltamethrin‐impregnated collars protect domestic dogs from sandfly bites
Authors: Halbig P. , Hodjati M. H. , Mazloumi‐Gavgani A. S. , Mohite H. , Davies C. R.
Published: March 2003

In many foci of zoonotic visceral leishmaniasis (ZVL), domestic dogs are important reservoir hosts of the causativeLeishmaniaparasites transmitted by phlebotomine sandflies (Diptera: Psychodidae). We tested the protective value of impregnated dog collars (20 g plastic containing deltamethrin 800 mg ai) againstPhlebotomus papatasi(Scopoli) sandflies in Iran. For each assay, the dog was sedated and caged in a net with 70–100 wild‐caught sandflies overnight (23.30–06.30 hours). Dogs wearing the collars were bitten by ∼80% fewer sandflies than before collars were fitted, i.e. 51% vs. 11% of hungry female flies exposed. Sandfly mortality rates following 20 h exposure to dogs with collars (18%) or without collars (17%) were not significantly different. Effects of collars were tested when dogs had been wearing them for 8 days. A previous trial against the sandflyP. perniciosusNewstead in France, using smaller dogs, showed that effects of such collars were not fully realized until they had been worn for 2 weeks or more; they remained effective for at least 8 months and killed significant proportions of the sandflies exposed. Present results withP. papatasi, confirming that this simple device provides effective protection against sandflies, are considered sufficiently encouraging to justify a community‐wide field trial of deltamethrin‐impregnated dog collars against ZVL vector sandflies in Iran.
Environmental information systems for the control of arthropod vectors of disease
Authors: Thomson M. C. , Connor S. J.
Published: March 2003

Over the last decade, remote sensing technologies and geographical information systems have moved from the research arena into the hands of vector control specialists. This review explains remote sensing approaches and spatial information technologies used for investigations of arthropod pests and vectors of diseases affecting humans and livestock. Relevant applications are summarized with examples of studies on African horse sickness vector Culicoides midges (Diptera: Ceratopogonidae), malaria vector Anopheles and arbovirus vector culicine mosquitoes (Diptera: Culicidae), leishmaniasis vector Phlebotomus sandflies (Diptera: Psychodidae), trypanosomiasis vector tsetse (Diptera: Glossinidae), loaiasis vector Chrysops (Diptera: Tabanidae), Lyme disease vector Ixodes and other ticks (Acari: Ixodidae). Methods and their uses are tabulated and discussed with recommendations for efficiency, caution and progress in this burgeoning field.
Experimental skin lesions from larvae of the bot fly Dermatobia hominis
Authors: Pereira M. C. T. , Leite V. H. R. , Leite A. C. R.
Published: March 2003

Skin biopsies from larvae of Rattus norvegicus, experimentally infested with Dermatobia hominis (Linnaeus Jr) (Diptera: Cuterebridae), were processed for histopathological studies. Two days after infestation, the first‐stage larvae (L1) were located deep in the dermis, surrounded by an inflamed area infiltrated predominantly by neutrophils. On the fourth day a thin necrotic layer could be seen close to the larvae, surrounded by large numbers of neutrophils, lymphocytes, macrophages with a few eosinophils and mast cells. A small warble was formed after the fourth day, increasing in size until the seventh day, when the L1 moulted to the second‐stage larva (L2). The inflammatory process continued with increasing numbers of neutrophils, macrophages, lymphocytes, eosinophils and mast cells invading the area, as well as the proliferation of fibroblasts and endothelial cells and the appearance of a few localized haemorrhages. After 18–20 days, the L2 moulted to the third‐stage larva (L3), when a few plasma cells could be seen in the inflamed area. At 25–30 days there was a reduction in the necrotic layer, as well as in the number of neutrophils and lymphocytes, although large amounts of eosinophils, plasma cells, and collagen fibres were seen. The L3 usually left the host after 30 days. Two days later, the larval cavity was reduced, mast cells infiltrated the region and collagen fibre production were increased. After 7 days, an intense infiltration of plasma cells and scattered necrotic areas could be seen. A scar formed after 10 days. This study showed the laboratory rat to be a suitable model for studies of D. hominis infestation.
Temephos‐resistant larvae of Simulium sanctipauli associated with a distinctive new chromosome inversion in untreated rivers of south‐western Ghana
Authors: Osei‐Atweneboana M. Y. , Wilson M. D. , Post R. J. , Boakye D. A.
Published: March 2003

Larvae of the Simulium damnosum Theobald complex (Diptera: Simuliidae) were sampled in June 1996 from two sites in south‐west Ghana where larviciding has not been applied: Sutri Rapids on the Tano river (05°23′ N 02°38′ W) and Sekyere‐Heman on the Pra river (05°11′ N 01°35′ W). All specimens were identified as Simulium sanctipauli Vajime & Dunbar sensu stricto (Diptera: Simuliidae). Bioassays with temephos (organophosphorus larvicide employed by the Onchocerciasis Programme for systematic treatment of most rivers across West Africa since the 1970s) showed about five‐fold resistance in the Tano population (LC95 2.37–3.14 mg/L) and slight tolerance to temephos in the Pra population (LC95 0.67–0.76 mg/L), vs. the diagnostic concentration of 0.625 mg/L. Larval salivary polytene chromosomes of S. sanctipauli showed fixed inversions 1S‐24/24, standard IIL‐6 and a new inversion IL/36 polymorphism at Sutri on the Tano. These karyotype characteristics differ from those of temephos‐resistant S. sanctipauli in rivers of Côte d'Ivoire and other sites on the Tano in Ghana. Thus, temephos resistance in S. sanctipauli at Sutri is associated with distinct chromosomal configurations, showing that immigration was unlikely. This resistance could have been locally selected by exposure of S. sanctipauli larval populations to agrochemicals run‐off from cocoa, coffee and oil plantations flanking the rivers.
Characterization of the screwworm flies Cochliomyia hominivorax and Cochliomyia macellaria by PCR‐RFLP of mitochondrial DNA
Authors: Litjens P. , Lessinger A. C. , De Azeredo–espin A. M. Lima
Published: March 2003

The primary screwworm fly Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae) is one of the most important insect pests of livestock in neotropical regions, whereas Cochliomyia macellaria (Fabricius) (Diptera: Calliphoridae), the secondary screwworm, is of medical and sanitary importance because of its role in the dissemination of pathogens. These two species share morphological similarities and both may occur in the same myiasis, but in different developmental stages. In this work, the usefulness of PCR‐RFLP (polymerase chain reaction – restriction fragment length polymorphism) of mitochondrial DNA (mtDNA) for the unambiguous identification of C. hominivorax and C. macellaria was investigated. Two specific regions of mtDNA were amplified: 870 bp from Cytochrome oxidase subunit I and 2100 bp from the A + T rich/12S region from C. hominivorax and C. macellaria specimens from different areas of Brazil. Reliable species‐specific PCR‐RFLP results were obtained for the CO I region and the A + T rich/12S region using the restriction enzymes Dra I and Ssp I. These results confirm the conservation of CO I diagnostic restriction sites previously reported and demonstrate the usefulness of the control region sequences as an efficient marker for PCR‐RFLP identification of Brazilian screwworm flies. The occurrences of intraspecific polymorphic patterns are discussed based on frequencies and potential conflicts for species identification. PCR‐RFLP provides a potentially useful method for identifying samples from the areas where these species are monitored.
Pteridine concentrations differ between insectary‐reared and field‐collected Anopheles albimanus mosquitoes of the same physiological age
Authors: PENILLA R. P. , RODRÍGUEZ M. H. , LÓPEZ A. D. , VIADER‐SALVADÓ J. M. , SÁNCHEZ C. N.
Published: March 2003

Abstract Biopterin, isoxanthopterin and 6‐pterincarboxylic acid were identified in the head of the malaria vector mosquito Anopheles albimanus Weidemann (Diptera: Culicidae) by HPLC. Total pteridine concentrations (TPC) were estimated in heads, body parts (BP: abdomen, legs and wings) and whole bodies of insectary‐reared and field‐collected females, by spectrofluorometry, to investigate whether they could be used for age determination. Pteridine concentrations diminished with age in both mosquito groups. TPC correlated with chronological age in insectary‐reared sugar‐fed females (heads: r2 = 0.35, BP: r2 = 0.34, P < 0.001), but lower correlation occurred in blood‐fed females (heads: r2 = 0.22, BP: r2 = 0.27). TPC differed among females of the same age fed with blood at different times (P < 0.05), indicating that bloodmeals modify the diminution rate of pteridines with age. Nevertheless, a polynomial significant correlation was documented for TPC and the number of ovipositions (heads: r2 = 0.24, BP: r2 = 0.27, whole body: r2 = 0.52, P < 0.001) in insectary‐reared mosquitoes. This correlation was lower in field‐collected mosquitoes (heads: r2 = 0.14, BP: r2 = 0.10, P < 0.05), which showed a remarkable pteridine increase in one‐parous females. The correlation of TPC in whole body with physiological age was much less (r2 = 0.03). These observations indicate that TPC determination by spectrofluorometry is not a reliable method to estimate the age of An. albimanus females from the feral population.
Teaching problem‐solving and clinical reasoning: 20 years experience with video‐supported small‐group learning
Authors: Dequeker  , Jaspaert
Published: March 2003

In the context of a curriculum reform the Faculty of Medicine of the University of Leuven, Belgium, introduced a new teaching project: video‐supported small‐group learning on problem‐solving and clinical reasoning. The aim of this study is to reflect 20 years experience. The video‐supported sessions for sixth‐year medical students during their practical year in peripheral hospitals were constructed in four stages. The first stage is the video presentation of a case with history‐taking and physical examination. The students and three tutors of internal medicine make notes and can ask further questions and perform additional physical examination acts after the video presentation. The coordinator of the course, who knows the patient, then simulates the patient and the doctor to answer the questions. The second stage consists of making up individually a synoptic problem list, integrating history and physical examination; a differential diagnosis list with the most likely diagnosis fitting the problem list; and a list with investigations to be asked for confirming the diagnosis. The third stage consists of three small student groups discussing the three lists requested in stage 2. Each small group of students, passively assisted by a tutor, has to come to the consensus lists. The fourth stage is the confrontation of the consensus lists of the three groups with the aim of coming to an overall agreement. At this stage tutors are more actively involved in the discussion. Several learning processes are involved in this way of teaching. During the first stage the students learn the traditional teaching `see one, do one and teach one', a demonstration of a full history and physical examination. By asking for additional information they learn by a critical attitude and by developing a strategy of fact‐finding. During the second and third stages, by making their lists and during the consensus processes, they learn the significance of individual findings, problem‐framing and the synthesis of history and physical examination data in medical concepts. The third and fourth parts of the sessions bring up the process of clinical reasoning, formulation of a working hypothesis, the discussion of the pathophysiology of findings, clustering of problems and epidemiological considerations as incidence and prevalence. Finally, the exercise to select diagnostic tests gives the students the possibility of appreciating the value of sensitivity/specificity and risks, benefits and costs of diagnostic procedures. These video‐supported clinical problem‐solving and reasoning sessions were positively appraised by students, teachers and medical faculty over the years. Over 20 years, more than 90 cases have been recorded on video, with a widespread variation in diagnoses and clinical presentations. Small‐group teaching with the aid of a video case, as described in this paper, can promote enjoyable learning for students and teachers.