bluuebunny/crossref_metadata_2025 huggingface dataset:
Low sleep quality and daytime sleepiness in obese patients without obstructive sleep apnoea syndrome
Authors: Resta O. , Foschino Barbaro M. P. , Bonfitto P. , Giliberti T. , Depalo A. , Pannacciulli N. , De Pergola G.
Published: December 2004

Abstract.  Resta O, Foschino‐Barbaro MP, Bonfitto P, Giliberti T, Depalo A, Pannacciulli N, De Pergola G (Respiratory Pathophysiology, University of Bari, School of Medicine, Bari, Italy; University of Foggia, School of Medicine, Foggia, Italy; and Internal Medicine, Endocrinology, and Metabolic Diseases, University of Bari, Bari, Italy). Low sleep quality and daytime sleepiness in obese patients without obstructive sleep apnoea syndrome. J Intern Med 2003; 253: 536–543.

Objectives.  To evaluate sleep quality, sleep‐related symptoms, and degree of excessive daytime sleepiness (EDS) in severe obesity, independently of obstructive sleep apnoea syndrome (OSAS).

Design.  A cross‐sectional study.

Setting.  Primary‐care setting.

Subjects, main outcome measures.  Anthropometric parameters, respiratory function data and sleep related symptoms were evaluated in 78 severely obese patients (aged 16–75 years) without OSAS and in 40 healthy sex‐ and age‐matched normal weight subjects, who underwent a full‐night polysomnography.

Results.  Obese patients and control subjects had similar sleep latency and rapid eye movement (REM) latency, but they showed lower percentage of REM (P < 0.01) and sleep efficiency (P < 0.05) than controls. All sleep‐related symptoms (observed or reported apnoea, awakenings, choking and unrefreshing sleep) were significantly more frequent in obese patients than in control subjects. Loud snoring was present in 46.7% of the obese patients and in 8.1% of the control individuals (P < 0.01). Excess daytime sleepiness was reported by 34.7% of the obese patients and by 2.7% of the normal weight subjects (P < 0.01). The Epworth Sleepiness Scale (ESS) was higher in the obese group than in the control group (P < 0.01), whereas arousals were not different between the two groups.

Conclusions.  This study clearly shows that severe obesity, even in the absence of OSAS, is associated with sleep‐related disorders and EDS. All these alterations may be partly responsible for a lower quality of life, a higher prevalence of medical complications, an increased risk of occupational injury, and both social and family problems characterizing obese patients, independently of the presence of OSAS.
Experience with lamivudine therapy for hepatitis B virus infection before and after liver transplantation, and review of the literature
Authors: Ben‐Ari Z. , Mor E. , Tur‐Kaspa R.
Published: December 2004

Abstract. Ben‐Ari Z, Mor E, Tur‐Kaspa R (Beilinson Campus, Petah Tikva, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel). Experience with lamivudine therapy for hepatitis B virus infection before and after liver transplantation, and review of the literature.J Intern Med2003;253:544–552.

Objectives. To analyse the results of lamivudine therapy on suppression of hepatitis B virus (HBV) replication before transplantation and on preventing graft reinfection postoperatively.

Design. Long‐term clinical study.

Setting. Liver Institute and Department of Transplantation of a tertiary‐care university‐affiliated centre.

Subjects. (1) 14 candidates for liver transplantation with decompensated liver disease caused by active replication of HBV; (2) six patients with recurrent HBV infection after transplantation.

Intervention. Lamivudine 100 mg daily; administered in group 1 before surgery and continued after in nine patients who underwent transplantation; administered in group two postoperatively only. antihepatitis B surface antigen immunoglobulin (HBIg) was administered postoperatively in both groups.

Main outcome measures. Immunoassay evaluation of serum hepatitis B surface antigen, serum hepatitis Be antigen and serum HBV DNA (hybridization and PCR); sequencing through the tyrosine‐methionine‐aspartate‐aspartate locus of the HBV polymerase gene in patients with lamivudine breakthrough; inflammation and fibrosis scoring on liver biopsy before and at least 2 years after lamivudine therapy in group 2.

Results. Pretransplantation therapy (group 1) significantly suppressed HBV replication and enabled nine patients (64.2%) to undergo transplantation. Only one patient (7.1%) had lamivudine breakthrough, and one (7.1%) had recurrent HBV. Lamivudine administration begun after transplantation (mean 48.0 months, range 30–60 months) because of graft reinfection (group 2) was associated, over the long‐term, with the emergence of high mutation rates (83.3%), histological disease progression (66.6%), and hepatic failure (33.3%).

Conclusions. In patients with chronic HBV infection and active viral replication, lamivudine therapy is effective when started before transplantation. However, its long‐term administration after transplantation for recurrent HBV leads to high resistance rates. Combination therapy with lamivudine and HBIg immunoglobulin can substantially reduce the recurrence rate. Further studies on combination antiviral therapy are needed in this patient population.
Health economics in the Hypertension Optimal Treatment (HOT) study: costs and cost‐effectiveness of intensive blood pressure lowering and low‐dose aspirin in patients with hypertension
Authors: Jönsson B. , Hansson L. , Stålhammar N.‐O.
Published: December 2004

Abstract. Jönsson B, Hansson L, Stålhammar N‐O (Stockholm School of Economics, Stockholm; University of Uppsala, Uppsala, Sweden; and AstraZeneca Pharmaceuticals, DE, USA). Health economics in the Hypertension Optimal Treatment (HOT) study costs and cost‐effectiveness of intensive blood pressure lowering and low‐dose aspirin in patients with hypertension.J Intern Med2003;253:472–480.

Objectives. To investigate the marginal cost‐effectiveness of different targets for the reduction of blood pressure and the cost‐effectiveness of adding acetylsalicylic acid (ASA) to the treatment of hypertension.

Design. Patients with hypertension were randomized to three target groups for blood pressure; ≤90, ≤85 and ≤80 mmHg. Patients were also randomly assigned ASA and placebo. The average follow‐up time was 3.8 years. The direct costs for drugs, visits, hospitalizations, and side‐effects were calculated and related to clinical outcome.

Setting. Resource utilization data from all the 26 countries in the study were pooled, and Swedish unit costs were applied to the aggregated resource utilization.

Subjects. A total of 18 790 patients, 50–80 years of age (mean 61.5 years), with a diastolic blood pressure between 100 and 115 mmHg (mean 105 mmHg).

Interventions. Antihypertensive treatment with the long‐acting calcium antagonist felodipine was given to all patients. Additional therapy and dose increments in four further steps were prescribed to reach the randomized target blood pressure. Fifty per cent of the patients were randomized to a low dose, 75 mg daily, of acetylsalicylic acid.

Main outcome measures. Direct health care costs, major cardiovascular (CV) events (myocardial infarction and stroke) and CV death.

Results. The average cost of drugs and visits increased with more intensive treatment. The increase in treatment costs was partly but not fully offset by a nonsignificant reduction in the cost of CV hospitalizations. For patients with diabetes there were no significant differences in total cost between the target groups. The cost of avoiding a major CV event was negative in the base case analysis, SEK −10 360 (CI: −78 195, 75 630), and SEK 18 450 (CI: −88 789, 192 980) in a sensitivity analysis. For patients on ASA, costs were slightly but significantly higher than for patients on placebo. The estimates of the cost of avoiding a major CV event varied between SEK 41 600 and SEK 477 400, with very wide confidence intervals.

Conclusions. The treatment cost increases as the target for hypertension treatment is lowered. In patients with diabetes, intensive treatment to a lower target is cost‐effective. Because of the nonsignificant difference in events, no conclusion can be made for all patients in the study. Furthermore, no conclusive evidence was found regarding the cost‐effectiveness of adding ASA to the treatment of hypertension.
Prediction of coronary heart disease: a comparison between the Copenhagen risk score and the Framingham risk score applied to a Dutch population
Authors: De Visser C. L. , Bilo H. J. G. , Thomsen T. F. , Groenier K. H. , Meyboom‐De Jong B.
Published: December 2004

Abstract.  de Visser CL, Bilo HJG, Thomsen TF, Groenier KH, Meyboom‐de Jong B (University of Groningen, Groningen; Isala Clinics, Weezenlanden location, Zwolle, The Netherlands; Glostrup University Hospital, Glostup, Denmark). Prediction of coronary heart disease: a comparison between the Copenhagen risk score and the Framingham risk score applied to a Dutch population. J Intern Med 2003; 253: 553–562.

Objectives.  To compare the estimation of coronary heart disease (CHD) risk by the Framingham risk score (FRS) and the Copenhagen risk score (CRS) using Dutch population data.

Design.  Comparison of CHD risk estimates from FRS and CRS. CHD risk‐estimations for each separate risk factor.

Setting.  Urk, the Netherlands.

Subjects.  A total of 408 fishermen from Urk, aged 30–65 years, without pre‐existing cardiovascular disease.

Main outcome measures.  Absolute CHD risk estimates.

Results.  The average 10‐year risk for CHD was significantly different between the FRS (4.6%, SD 5.0) and the CRS (3.2%, SD 4.1). The correlation between the two estimates was 0.94 (P < 0.001). The Bland–Altman figure shows a large proportion of agreement, but with an increasing difference with increasing average risk. When examining the separate risk factors age, total cholesterol, HDL cholesterol and systolic blood pressure and smoking, there appear differences between the two risk functions.

Conclusion.  Using Dutch population data, differences were found for the calculation of CHD risk with the FRS and the CRS. Further research must be carried out to examine the validity of these risk functions in the Dutch population.
Lung function, insulin resistance and incidence of cardiovascular disease: a longitudinal cohort study
Authors: Engström G. , Hedblad B. , Nilsson P. , Wollmer P. , Berglund G. , Janzon L.
Published: December 2004

Abstract.  Engström G, Hedblad B, Nilsson P, Wollmer P, Berglund G, Janzon L (University of Lund, Malmö University Hospital, Malmö, Sweden). Lung function, insulin resistance and incidence of cardiovascular disease: a longitudinal cohort study. J Intern Med 2003; 253: 574–581.

Objectives.  To explore whether a reduced lung function is a risk factor for developing diabetes and insulin resistance (IR), and whether such relationship contributes to the largely unexplained association between lung function and incidence of cardiovascular disease (CVD).

Design.  Forced vital capacity (FVC) was assessed at baseline. Incidence of diabetes and IR [according to the homeostasis model assessment (HOMA) model] was assessed in a follow‐up examination after 13.9 ± 2.6 and 9.4 ± 3.6 years for men and women, respectively. After the follow‐up examination, incidence of CVD (stroke, myocardial infarction or cardiovascular death) was monitored over 7 years.

Setting.  Populations‐based cohort study.

Subjects.  Initially nondiabetic men (n = 1436, mean age 44.6 years) and women (n = 896, mean age 49.8 years).

Results.  Prevalence of IR at the follow‐up examination was 34, 26, 21 and 21%, respectively, for men in the first (lowest), second, third and fourth quartile of baseline FVC (P for trend <0.0001). The corresponding values for women were 30, 29, 25 and 17%, respectively (P for trend <0.001). Adjusted for potential confounders, the odds ratio (OR) for IR (per 10% increase in FVC) was 0.91 (CI: 0.84–0.99) for men and 0.89 (CI: 0.80–0.98) for women. FVC was similarly significantly associated with the incidence of diabetes (OR = 0.90, CI: 0.81–1.00), adjusted for sex and other confounders.

The incidence of CVD after the follow‐up examination was significantly increased only amongst subjects with low FVC who had developed IR (RR = 1.7, CI: 1.02–2.7).

Conclusion.  Subjects with a moderately reduced FVC have an increased risk of developing IR and diabetes. This relationship seems to contribute to the largely unexplained association between reduced lung function and incidence of CVD.
Prognosis of hepatocellular carcinoma in anti‐HCV positive cirrhotic patients: a single‐centre comparison amongst four different staging systems
Authors: Giannini E. , Risso D. , Botta F. , Romagnoli P. , Malfatti F. , Fumagalli A. , Testa E. , Podestà E. , Chiarbonello B. , Polegato S. , Testa R.
Published: December 2004

Background.  Epidemiological studies have foreseen an increase in the incidence of hepatocellular carcinoma (HCC) in the near future and it is estimated that this trend will mostly affect hepatitis C virus (HCV) positive cirrhotic patients. Therefore, accuracy of HCC staging is an important clinical issue.

Aim.  To investigate the prognostic usefulness of a series of newly proposed HCC prognostic systems such as the Cancer of the Liver Italian Program (CLIP) score, the Groupe d'Etude et de Traitement du Carcinome Hépatocellulaire (GRETCH) model and the Barcelona Clinic Liver Cancer (BCLC) staging classification when compared with the usefulness of a known staging system such as the Okuda staging system in a group of anti‐HCV positive cirrhotic patients with HCC seen at a single centre.

Methods.  Okuda stage, CLIP score, GRETCH model and BCLC stages were retrospectively computed in 81 anti‐HCV positive cirrhotic patients with HCC. We evaluated and compared the ability of these methods to assess survival prognosis.

Results.  As of December 2001, 51 patients had died and overall median survival was 18 months. All the staging systems were able to identify various patient subgroups with different survival. The CLIP score, the GRETCH model and the BCLC staging classification were better at characterizing the 1‐year prognosis of the patients when compared with the Okuda staging system, whilst the 3‐year prognostic evaluation was improved only by using the CLIP score or the BCLC staging classification.

Conclusions.  The prognostic value and usefulness of the CLIP score, the GRETCH model and the BCLC staging classification was reproduced in a single‐centre analysis of anti‐HCV positive HCC cirrhotic patients. These scores provided a prognostic assessment of our patients which is superior to what was obtained by the Okuda staging system.
Iontophoresis of dexamethasone‐phosphate into the equine tibiotarsal joint
Authors: BLACKFORD J. , DOHERTY T. J. , FERSLEW K. E. , PANUS P. C.
Published: December 2004

In human rehabilitation medicine, dexamethasone‐phosphate is theoretically iontophoresed to localized subcutaneous tissue where conversion to dexamethasone occurs. This delivery system has recently been introduced into veterinary medicine for the same purpose. However, the pharmacokinetic justification for parenteral delivery of this prodrug remains undocumented. Utilizing iontophoretic methods that are relevant to both human and veterinary clinical practice, the present investigation compared injection and iontophoresis of dexamethasone‐phosphate into the equine tibiotarsal joint, also known as the tarsocrual joint. The tibiotarsal joints of seven horses were injected with 4 mL of 6 mg/mL dexamethasone‐phosphate. With a similar drug concentration and over the same application site, six different horses underwent simultaneous cathodic iontophoresis (4 mA, 40 min) or passive application (0 mA, 40 min) on contralateral limbs. Following all applications, tibiotarsal joint synovium was collected. Local venous blood samples were also collected from the iontophoretic and passive application sites for analysis of plasma drug concentrations. Because of the potential for conversion of dexamethasone‐phosphate to dexamethasone, an extraction and analysis protocol was developed for both chemicals. The technique demonstrated a linear range of detection (0.39–12 μg/mL) and a capability for measuring both chemicals in plasma and synovium. Conversion of dexamethasone‐phosphate to dexamethasone occurred during synovial incubation (37 °C) and following freeze–thaw cycles. In contrast to the measurable synovial concentrations of dexamethasone‐phosphate (2.3±0.96 mg/mL) and dexamethasone (0.27±0.07 mg/mL) following injection, neither drug was detected in the synovium or the local venous blood following iontophoretic or passive applications. In conclusion, these results do not confirm iontophoretic or passive delivery of measurable dexamethasone‐phosphate into the tibiotarsal joint using current clinical methods.
Intratracheal clenbuterol in the horse: its pharmacological efficacy and analytical detection
Authors: HARKINS J. D. , ROBINSON N. E. , WOODS W. E. , LEHNER A.F. , SMITH M. D. , GATES R. S. , FISHER M. , TOBIN T.
Published: December 2004

Clenbuterol, a β2 agonist/antagonist, is the only bronchodilator approved by the US Food and Drug Administration for use in horses. The Association of Racing Commissioners International classifies clenbuterol as a class 3 agent, and, as such, its identification in post‐race samples may lead to sanctions. Anecdotal reports suggest that clenbuterol may have been administered by intratracheal (IT) injection to obtain beneficial effects and avoid post‐race detection. The objectives of this study were (1) to measure the pharmacological efficacy of IT dose of clenbuterol and (2) to determine the analytical findings in urine in the presence and absence of furosemide. When administered intratracheally (90 μg/horse) to horses suffering from chronic obstructive pulmonary disease (COPD), clenbuterol had effects that were not significantly different from those of saline. In parallel experiments using a behavior chamber, no significant effects of IT clenbuterol on heart rate or spontaneous locomotor activity were observed. Clenbuterol concentrations in the urine were also measured after IT dose in the presence and absence of furosemide. Four horses were administered i.v. furosemide (5 mg/kg), and four horses were administered saline (5 mL). Two hours later, all horses were administrated clenbuterol (IT, 90 μg), and the furosemide‐treated horses received a second dose of furosemide (2.5 mg/kg, i.v.). Three hours after clenbuterol dose (1 h after hypothetical ‘post‐time’), the mean specific gravity of urine samples from furosemide‐treated horses was 1.024, well above the 1.010 concentration at which furosemide is considered to interfere with drug detection. There was no interference by furosemide with ‘enhanced’ ELISA screening of clenbuterol equivalents in extracted and concentrated samples. Similarly, furosemide had no effect on mass spectral identification or quantification of clenbuterol in these samples. These results suggest that the IT dose of clenbuterol (90 μg) is, in pharmacological terms, indistinguishable from the dose of saline, and that, using extracted samples, clenbuterol dose is readily detectable at 3 h after dosing. Furthermore, concomitant dose of furosemide does not interfere with detection or confirmation of clenbuterol.
Pharmacokinetics and pharmacodynamics of clemastine in healthy horses
Authors: Törneke K. , Ingvast‐Larsson C. , Pettersson K. , Bergvall K. , Hedeland M , Bondesson U , BrostrÖm H.
Published: December 2004

Clemastine is an H1 antagonist used in certain allergic disorders in humans and tentatively also in horses, although the pharmacology of the drug in this species has not yet been investigated. In the present study we determined basic pharmacokinetic parameters and compared the effect of the drug measured as inhibition of histamine‐induced cutaneous wheal formation in six horses.

The most prominent feature of drug disposition after intravenous dose of 50 μg/kg bw was a very rapid initial decline in plasma concentration, followed by a terminal phase with a half‐life of 5.4 h. The volume of distribution was large, Vss = 3.8 L/kg, and the total body clearance 0.79 L/h kg. Notably, oral bioavailability was only 3.4%. There was a strong relationship between plasma concentrations and effect. The effect maximum (measured as reduction in histamine‐induced cutaneous wheal formation) was 65% (compared with controls where saline was injected) and the effect duration after i.v. dose was approximately 5 h. The effect after oral dose of 200 μg/kg was minor.

The results indicate that clemastine is not appropriate for oral administration to horses because of low bioavailability. When using repeated i.v. administration, the drug has to be administered at least three to four times daily to maintain therapeutic plasma concentrations because of the short half‐life. However, if sufficient plasma concentrations are maintained the drug is efficacious in reducing histamine‐induced wheal formations.
Influence of age and date of infection on distribution of hepatitis C virus genotypes and fibrosis stage
Authors: Serra M. A. , Rodríguez F. , Del Olmo J. A. , Escudero A. , Rodrigo J. M.
Published: December 2004

Summary.  The objective of this study was to assess the influence of age and date of acquisition of hepatitis C virus (HCV) infection on the distribution of genotypes and the progression of fibrosis in HCV‐infected patients who were born in Spain and had their habitual place of residence in this country. Genotypic analysis was performed in 375 patients in whom it was possible to establish the year of HCV infection because the mode of transmission was known (transfusion, injection drug use, blood donor, or epidemic outbreak). In 298 patients with liver biopsy, fibrosis stage was related to age at infection, duration of infection, alcohol consumption, and HCV genotype. HCV subtype 1b was almost exclusively detected among transfusion recipients, but the onset of intravenous drug addiction was associated with the introduction of HCV genotypes other than 1b among injecting users with subsequent spread to other exposure risk groups. Fibrosis progression was influenced by alcohol consumption, increased duration of infection, and older age at infection. In summary, spread of intravenous drug use determined HCV infection by genotypes other than 1b. The risk of fibrosis progression was influenced more by age at viral acquisition and alcohol consumption than by the infecting genotype.
Interferon α in the treatment of chronic hepatitis C in children: a metanalysis
Authors: Ciommo V. Di , Russo P. , Ravà L. , Caprino L.
Published: December 2004

Summary. Children with chronic hepatitis C may be ideal candidates for treatment with interferon alpha (IFNα) as they have liver disease at an early stage. However, adverse drug reactions need to be considered. The aim of this study was to conduct a systematic review of literature on interferon therapy of chronic hepatitis C in children, and to perform a metanalysis of pooled data. A computerized search gave 18 articles on IFNα therapy in children with chronic hepatitis C; after exclusion of uncontrolled trials and of trials including patients with comorbidities, data from two studies could be pooled (48 patients). The outcomes assessed were biochemical, defined as normalization of alanine transaminase, and virologic, defined as HCV‐RNA loss, both sustained at 24 months after enrolment. Results of the studies were homogenous. Risk difference was 37% (95%CI: 12.9–61) in favour of IFNα treated children for sustained biochemical response, and 36.8% (95%CI: 14.3–59.3) in favour of treated children for sustained HCV clearance, respectively. The differences were highly significant (P = 0.007 and P = 0.004, respectively). The histological end‐point, as well as side‐effects, could not be analysed, due to lack of data. This review identifies the poor methodology of the majority of the published trials. The study provides support for the efficacy of IFNα in improving both biochemical and virologic outcomes in chronic hepatitis C in children, but evidence is confined to these surrogate end‐points.
Chronic hepatitis C patients with a post‐treatment virological relapse re‐treated with an induction dose of 18 MU interferon‐α in combination with ribavirin and amantadine: a two‐arm randomized pilot study
Authors: Weegink C. J. , Sentjens R. E. , Beld M. G. , Dijkgraaf M. G. W. , Reesink H. W.
Published: December 2004

Summary. Thirty‐seven chronic hepatitis C patients with virological relapse (VR) after previous interferon‐α (IFN) or IFN/ribavirin (Riba) therapy, were re‐treated. Patients were randomized for either IFN/Riba and amantadine (Ama) including a 2‐week initial high IFN induction course (18 MU IFN daily) (group A) or the same 2‐week IFN induction course combined with Riba/Ama, followed by Riba/Ama without IFN (group B). Treatment duration for both groups was 24 weeks with a 24‐week follow‐up thereafter. The inclusion in group B was prematurely stopped because all patients (n = 10) relapsed within 2 weeks after stopping IFN. Therefore, all subsequent patients were included in group A (n = 27). In group A, 44% achieved a sustained virological response (SVR) and 29% of the patients with an end‐of‐treatment virological response had a VR again. Of all pretreatment characteristics, only genotype non‐1 patients had a significantly higher chance of achieving SVR (P < 0.001). Of the characteristics during treatment only a negative hepatitis C virus (HCV)‐RNA test result in transcription‐mediated amplification (TMA) at week 6 had a high predictive value for SVR, 80% in all patients and 92% in genotype non‐1 patients. In conclusion, hepatitis C patients with a VR to previous antiviral treatment can be succesfully re‐treated with IFN induction combined with Riba/Ama for only 6 months, when they have genotype non‐1 and a negative HCV‐RNA test result in TMA 6 weeks after the start of therapy. Riba/Ama combination therapy without IFN does not prevent VR after 2 weeks high IFN induction.
YSDD: a novel mutation in HBV DNA polymerase confers clinical resistance to lamivudine
Authors: Bozdayi̇ A. M. , Uzunalimoğlu Ö. , Türkyi̇lmaz A. R. , Aslan N. , Sezgin O. , Sahin T. , Bozdayi̇ G. , Çi̇nar K. , Pai S. B. , Pai R. , Bozkaya H. , Karayalçi̇n S. , Yurdaydi̇n C. , Schinazi R. F.
Published: December 2004

Summary.  The emergence of drug‐resistant virus in hepatitis B virus (HBV) patients treated with lamivudine is well documented. In this study, we determined the mutations occurring in the tyrosine–methionine–aspartate–aspartate (YMDD) amino acid motif of the HBV DNA polymerase gene, as well as upstream and downstream of this region, in patients with breakthrough virus during lamivudine therapy. Thirty‐one Turkish patients (20 patients HBeAg positive, 11 patients HBeAg negative and anti‐HBe positive) with chronic HBV infection who completed at least 104 weeks of lamivudine treatment were investigated. All patients received lamivudine, (150 mg/day), for 104 weeks, with or without 4 months of interferon (IFN) combination. HBV‐specific sequences were amplified by polymerase chain reaction (PCR) from sera of patients with breakthrough virus, and the PCR products were directly analysed by sequencing. Breakthrough virus was detected in seven of the 31 patients (22.6%) between 9 and 18 months of therapy. Of the seven patients, six were HBeAg positive at baseline, and four had a double mutation consisting of rtM204V and rtL180M, while two had an rtM204I change. In one patient, two base substitutions at rt204 (ATG → AGT; T to G and G to T) lead to a methionine to serine change (YMDD → YSDD). This novel DNA pol mutation was detected at month 18 of lamivudine treatment. In addition, this new variant had the rtL180M mutation and a 12 base pair deletion in the pre‐S1 region between nucleotides 43–54. The YSDD mutation was still present 6 months after lamivudine discontinuation.In vitro transfection studies also confirmed that the YSDD strain is resistant to lamivudine. In conclusion, the results indicate that, in addition to a Met → Val and Met → Ile change in YMDD, a Met → Ser change at rt204 (YMDD → YSDD) associated with the rtL180M change can also emerge during lamivudine treatment, which confers lamivudine resistance in vivo and in vitro, leading to virological breakthrough and ALT increases.
Factors affecting the distribution of small mammals in an urban area
Authors: BAKER PHILIP J. , ANSELL RACHEL J. , DODDS PHILLIPPA A. A. , WEBBER CLAIRE E. , HARRIS STEPHEN
Published: December 2004

We investigated the distribution of a range of small mammal species in five urban habitats in north‐west Bristol: residential gardens, woodlands, allotment gardens, scrub and a cemetery. Wood mouse Apodemus sylvaticus abundance in residential gardens was negatively related to the abundance of cats and the distance to the nearest patch of natural or seminatural vegetation. These results suggest that urban small mammal populations may be limited by predation and habitat fragmentation, although the effects of the latter may be offset by the availability of good quality gardens.
The distribution and status of the polecat Mustela putorius in Luxembourg
Authors: BAGHLI ADIL , VERHAGEN RONALD
Published: December 2004

1. The presence and distribution of the polecat Mustela putorius in Luxembourg was studied for the first time. Postal surveys were conducted among all the tenants of the hunting areas and all the farmers in the country.

2. Except for the otter Lutra lutra, the polecat appears to be the least common mustelid in Luxembourg. Farmers and hunters perceived the polecat differently according to their interests. Farmers had a more tolerant attitude towards the species but 17% still considered it a pest.

3. Live trapping of polecats was carried out for 3 years: 16 individuals were caught. This suggests a very low population density. Hunting records of this mustelid were examined for the period 1955–2000. There has been a very strong decrease in the number of polecats killed, giving rise to concerns that its population may be dramatically declining. Moreover, hunting data from neighbouring Germany confirm that this is a regional situation.
The distribution of mountain haresLepus timidusin Europe: a challenge from brown haresL. europaeus?
Authors: THULIN CARL‐GUSTAF
Published: December 2004

1. Throughout the most recent glacial period (Weichsel), the mountain hareLepus timidushad a continuous distribution in the tundra habitat south of the ice‐rim. When the ice retreated, mountain hares colonized deglaciated land, and spread over northern Europe.

2. Since the Weichsel, the mountain hare's distribution in Europe has been gradually reduced and at present comprises Ireland and the Scottish Highlands, high altitudes in the Alps, isolated forests in eastern Poland, most of Fennoscandia and from the Baltic countries eastwards through Russia. Declines during the last century have been observed in Sweden and Russia.

3. This review defines and evaluates causes for this gradual reduction and fragmentation of the mountain hare's distribution, with special focus on interactions with brown haresLepus europaeus. The relative importance of diseases, predation, cultivation and interactions with other herbivores than brown hares are discussed.

4. A plausible cause of the possible permanent disappearance of mountain hares in Europe appears to be exclusion by interspecific competition and hybridization with, and/or epidemic diseases mediated by, the congeneric brown hare.
Diet of wild boar Sus scrofa in Western Europe, with particular reference to consumption of agricultural crops
Authors: SCHLEY LAURENT , ROPER TIMOTHY J.
Published: December 2004

1. The diet of wild boar Sus scrofa in Western Europe is reviewed, paying particular attention to the consumption of agricultural crops and the implications of this from the point of view of crop damage. Data were taken mainly from 11 studies that provide quantitative information about the consumption of different food types, but we also list all the foods reported as being eaten by wild boar in a total of 21 studies.

2. Vegetable foods occurred more frequently in the diet than animal foods, and also constituted the bulk of the food ingested. Overall, there were four major vegetable food categories: mast, roots, green plant matter and agricultural crops. Depending on the study area, wild boar always consumed at least one energy‐rich plant food such as acorns, beechnuts, chestnuts, pine seeds, olives, cereal grains or other crops. The number and types of agricultural crops consumed varied between study areas but crops represent an important component of wild boar diet throughout its Western European range. Among animal foods, insects, earthworms, birds and mammals were eaten most consistently but the diet also included amphibians, reptiles, gastropods and myriapods.

3. Seasonal, interannual and regional differences in the diet, together with its striking overall breadth, indicate that wild boar are opportunistic omnivores whose diet, in any particular instance, is largely determined by the relative availability of different food types. Dependence on energy‐rich plant material as a major component of the diet, coupled with large body size and a propensity to trample crops as well as consume them, means that wild boar cause significant agricultural damage.
Contrasting selection pressures on components of the Ras‐mediated signal transduction pathway in Drosophila
Authors: Riley Rebecca M. , Jin WeI , Gibson Greg
Published: December 2004

The molecular genetics of several signal transduction pathways is well characterized, providing an opportunity to address the nature of the population genetic forces acting on functionally related suites of pleiotropic regulatory genes. Signal transduction is the process by which signals are transmitted from the cell surface to the nucleus or other cellular structures. It plays a fundamental role in regulating a wide range of developmental and physiological processes, many of which are likely to be subject to buffering mechanisms. Here we infer that contrasting selection pressures act on six components of the Ras signal transduction pathway by comparing sequences obtained from 25 alleles of Drosophila melanogaster with one allele of the sibling species D. simulans. The three most upstream components of the cascade, Ras, Drk and polehole, experience strong purifying selection, as they show no fixed amino acid differences between the species and just a handful of rare replacement polymorphisms within D. melanogaster. This portion of the pathway is likely to act as a control point in signal transduction, because the more downstream components Dsor1, corkscrew and Ksr, each show several amino acid replacements between the species. Furthermore, Ksr is nearly monomorphic within D. melanogaster, and application of the HKA and McDonald and Kreitman tests indicate that this gene may have experienced a recent selective sweep, suggesting that modifiers of Ras kinase signalling are the most likely source of quantitative variation associated with this core regulatory pathway.
Effect of heat shock, pretreatment and hsp70 copy number on wing development in Drosophila melanogaster
Authors: Williams Karen D. , Helin Amanda B. , Posluszny Joseph , Roberts Stephen P. , Feder Martin E.
Published: December 2004

Naturally occurring heat shock (HS) during pupation induces abnormal wing development in Drosophila; we examined factors affecting the severity of this induction. The proportion of HS‐surviving adults with abnormal wings varied with HS duration and intensity, and with the pupal age or stage at HS administration. Pretreatment (PT), mild hyperthermia delivered before HS, usually protected development against HS. Gradual heating resembling natural thermal regimes also protected wing development against thermal disruption. Because of the roles of the wings in flight and courtship and in view of natural thermal regimes that Drosophila experience, both HS‐induction of wing abnormalities and its abatement by PT may have marked effects on Drosophila fitness in nature. Because PT is associated with expression of heat‐inducible molecular chaperones such as Hsp70 in Drosophila, we compared thermal disruption of wing development among hsp70 mutants as well as among strains naturally varying in Hsp70 levels. Contrary to expectations, lines or strains with increased Hsp70 levels were no more resistant to HS‐disruption of wing development than counterparts with lower Hsp70 levels. In fact, wing development was more resistant to HS in hsp70 deletion strains than control strains. We suggest that, while high Hsp70 levels may aid cells in surviving hyperthermia, high levels may also overly stimulate or inhibit numerous signalling pathways involved in cell proliferation, maturation and programmed death, resulting in developmental failure.
Nuclear gene sequences and DNA variation of Cryptomeria japonica samples from the postglacial period
Authors: Tani Naoki , Tsumura Yoshihiko , Sato Hitoshi
Published: December 2004

Genomic DNA was extracted from heartwood blocks of six Cryptomeria japonica individuals that had been buried (in an area now covered by rice fields) for about 3600 years. Attempts were made to determine the sequences of five nuclear genes following polymerase chain reaction amplification, using previously obtained C. japonica expressed sequence tag (EST) information. We detected 15 nucleotide substitutions and four insertion/deletions (indels) in a partial GapC gene sequence among 13 individuals of the buried and an extant population, which allowed us to estimate the extent of DNA variation within the buried populations, and the level of genetic differentiation between the buried population and the extant population growing in a neighbouring area. For the entire haplotypes of the GapC region, π and θ nucleotide diversity estimates were 0.0063 and 0.0010, respectively, when both populations were included, while corresponding figures for the buried population alone were 0.0009 and 0.0017. Estimates of DNA divergence statistics (dXY = 0.0062, dA = 0.0005, FST = 0.0832 and KST = 0.0935) suggest that differentiation between the two populations was not great. However, permutation tests gave FST and KST values rejecting the null hypothesis (that populations were not differentiated) at the 5% and 1% probability levels, respectively. The significant genetic differentiation between the two populations was mainly caused by differences in haplotype diversity. The significant level of haplotype diversity in the extant population compared to the buried population might be the result of gene flow from neighbouring artificial forests. Alternatively, it is possible that we failed to detect all the DNA variation in the buried population because of clonal growth in the buried population.
Side‐stepping secondary symbionts: widespread horizontal transfer across and beyond the Aphidoidea
Authors: Russell J. A. , Latorre A. , Sabater‐Muñoz B. , Moya A. , Moran N. A.
Published: December 2004

To elucidate the co‐evolutionary relationships between phloem‐feeding insects and their secondary, or facultative, bacterial symbionts, we explore the distributions of three such microbes — provisionally named the R‐type (or PASS, or S‐sym), T‐type (or PABS), and U‐type — across a number of aphid and psyllid hosts through the use of diagnostic molecular screening techniques and DNA sequencing. Although typically maternally transmitted, phylogenetic and pairwise divergence analyses reveal that these bacteria have been independently acquired by a variety of unrelated insect hosts, indicating that horizontal transfer has helped to shape their distributions. Based on the high genetic similarity between symbionts in different hosts, we argue that transfer events have occurred recently on an evolutionary timescale. In several instances, however, closely related symbionts associate with related hosts, suggesting that horizontal transfer between distant relatives may be rarer than transmission between close relatives. Our findings on the prevalence of these symbionts within many aphid taxa, along with published observations concerning their effects on host fitness, imply a significant role of facultative symbiosis in aphid ecology and evolution.
Analysis of a chalcone synthase mutant in Ipomoea purpurea reveals a novel function for flavonoids: amelioration of heat stress
Authors: Coberly L. C. , Rausher M. D.
Published: December 2004

Flavonoids are thought to function in the plant stress response and male fertility in some, but not all, species. We examined the effects of a self‐fertile chalcone synthase null allele, a, for the effects of heat and light stress on fertilization success and flower production in Ipomoea purpurea. Pollen recipients and pollen donors of both homozygous genotypes exhibit reduced fertilization success at high temperatures, indicating that high temperature acts as a stress‐lowering fertilization success. Homozygous aa individuals exhibit reduced male and female fertilization success, compared to AA individuals, at high temperatures but not at low temperatures. In addition, aa individuals produce fewer flowers than AA individuals at low temperatures, but not at high temperatures. These results suggest that flavonoids alleviate heat stress on fertilization success. They also suggest that pleiotropic effects at the A locus may explain the low frequency of the a allele in natural populations.
Different genes underlie adaptive melanism in different populations of rock pocket mice
Authors: Hoekstra H. E. , Nachman M. W.
Published: December 2004

Identifying the genes responsible for adaptation has been an elusive goal in evolutionary biology. Rock pocket mice (Chaetodipus intermedius) provide a useful system for studying the genetics of adaptation: mostC. intermediusare light‐coloured and live on light‐coloured rocks, but in several different geographical regions,C. intermediusare melanic and live on dark‐coloured basalt lava, presumably as an adaptation for crypsis. Previous work demonstrated that mutations at the melanocortin‐1 receptor gene (Mc1r) are responsible for the dark/light difference in mice from one population in Arizona. Here, we investigate whether melanism has evolved independently in populations of darkC. intermediusfrom New Mexico, and whether the same or different genes underlie the dark phenotype in mice from these populations compared with the dark mice from Arizona. Seventy‐six mice were collected from pairs of dark and light localities representing four different lava flows and adjacent light‐coloured rocks; lava flows were separated by 70–750 km. Spectrophotometric analysis of mouse pelage and of rock samples revealed a strong positive association between coat colour and substrate colour. No significant differences were observed in the colour of rocks among the four lava flows, suggesting that mice in these separate populations have experienced similar selection for crypsis. Despite this similarity in environment, melanic mice from the three New Mexico populations were slightly, but significantly, darker than melanic mice from Arizona. The entireMc1rgene was sequenced in all mice. The previously identified mutations responsible for the light/dark difference in mice from Arizona were absent in all melanic mice from three different populations in New Mexico. Five newMc1rpolymorphisms were observed among mice from New Mexico, but none showed any association with coat colour. These results indicate that adaptive melanism has arisen at least twice inC. intermediusand that these similar phenotypic changes have a different genetic basis.
Prospects for inferring pairwise relationships with single nucleotide polymorphisms
Authors: Glaubitz Jeffrey C. , Rhodes O. Eugene , Dewoody J. Andrew
Published: December 2004

An extraordinarily large number of single nucleotide polymorphisms (SNPs) are now available in humans as well as in other model organisms. Technological advancements may soon make it feasible to assay hundreds of SNPs in virtually any organism of interest. One potential application of SNPs is the determination of pairwise genetic relationships in populations without known pedigrees. Although microsatellites are currently the marker of choice for this purpose, the number of independently segregating microsatellite markers that can be feasibly assayed is limited. Thus, it can be difficult to distinguish reliably some classes of relationship (e.g. full‐sibs from half‐sibs) with microsatellite data alone. We assess, via Monte Carlo computer simulation, the potential for using a large panel of independently segregating SNPs to infer genetic relationships, following the analytical approach of Blouin et al. (1996). We have explored a ‘best case scenario’ in which 100 independently segregating SNPs are available. For discrimination among single‐generation relationships or for the identification of parent–offspring pairs, it appears that such a panel of moderately polymorphic SNPs (minor allele frequency of 0.20) will provide discrimination power equivalent to only 16–20 independently segregating microsatellites. Although newly available analytical methods that can account for tight genetic linkage between markers will, in theory, allow improved estimation of relationships using thousands of SNPs in highly dense genomic scans, in practice such studies will only be feasible in a handful of model organisms. Given the comparable amount of effort required for the development of both types of markers, it seems that microsatellites will remain the marker of choice for relationship estimation in nonmodel organisms, at least for the foreseeable future.
Clonal diversity and genetic differentiation in Ilex leucoclada M. patches in an old‐growth beech forest
Authors: Torimaru T. , Tomaru N. , Nishimura N. , Yamamoto S.
Published: December 2004

We investigated clonal diversity within patches of Ilex leucoclada and genetic variation within and among patches using random amplified polymorphic DNA (RAPD) markers in a 1‐ha plot within an old‐growth beech forest. We found 38 patches that exhibited a clumped distribution in the middle of the plot. We identified a total of 166 RAPD phenotypes among the 215 stems sampled from 27 patches that were completely within the plot. The population showed high clonal diversity within patches (mean number of genets relative to number of stems = 0.79; mean Simpson's D= 0.89). Variation in RAPD phenotypes among patches was highly significant (ΦST in the molecular variance analysis = 0.316, P < 0.001), indicating genetic differentiation among patches. Pairwise genetic distances, ΦST, among patches did not correlate with geographical distances among patches. The cluster analysis based on the genetic distances showed few clear clusters of patches, indicating no spatial genetic structure among patches. High levels of clonal diversity both within patches and within the population may be explained by multiple founders, seedling recruitment during patch‐formation, and somatic mutation. The significant genetic differentiation among patches may be caused by separate founding events and/or kin structuring within patches.