bluuebunny/crossref_metadata_2025 huggingface dataset:
Non‐endothelial KDR/flk‐1 expression is associated with increased survival of patients with urothelial bladder carcinomas
Authors: Gakiopoulou‐Givalou H , Nakopoulou L , Panayotopoulou E G , Zervas A , Mavrommatis J , Giannopoulos A
Published: December 2004

Aims:  To investigate the immunohistochemical expression of KDR/flk‐1 in a series of 114 urothelial bladder carcinomas in relation to clinicopathological parameters, Ki67, p53 and Bcl‐2 protein expression and patient survival. KDR/flk‐1 is a high‐affinity tyrosine kinase receptor for vascular endothelial growth factor (VEGF), on vascular endothelium. However, there is increasing evidence that KDR/flk‐1 is also expressed by normal non‐endothelial and tumour cells.

Methods and results:  Immunohistochemistry was performed on paraffin sections using monoclonal and polyclonal antibodies. Statistical analysis was univariate (χ2 log rank test) and multivariate (Cox's model). KDR/flk‐1 expression was observed in the cytoplasm of cancerous cells in 68.4% of cases. No statistically significant associations were observed between KDR/flk‐1 expression and grade or stage of urothelial carcinomas, Ki67, p53 or Bcl‐2 expression. In contrast, widespread KDR/flk‐1 expression in more than 50% of cancerous cells was associated with increased survival, on univariate and multivariate analysis (P = 0.0119 and P = 0.042, respectively).

Conclusions:  Although the biological significance of non‐endothelial KDR/flk‐1 expression has not yet been elucidated, its association with better patient survival may be related to the failure of non‐endothelial KDR/flk‐1 to mediate angiogenic and mitogenic effects.
Loss of oestrogen receptor β, high PCNA and p53 expression and aneuploidy as markers of worse prognosis in ovarian granulosa cell tumours
Authors: Staibano S , Franco R , Mezza E , Chieffi P , Sinisi A , Pasquali D , Errico M E , Nappi C , Tremolaterra F , Somma P , Mansueto G , De Rosa G
Published: December 2004

Aims:  Ovarian granulosa cell tumour (OGCT) is a sex‐cord stromal tumour with a general trend toward late relapse and/or metastasis. However, mortality rate corrected for long‐term follow‐up shows that about 50% of patients die within 20 years of diagnosis. Classical clinicopathological parameters are unable to predict the biological behaviour of OGCT. The involvement of a recently characterized subtype of oestrogen receptor, ERβ, in ovarian carcinogenesis has been hypothesized.

Methods and results:  We examined by immunohistochemistry the expression of ERβ, proliferating cell nuclear antigen (PCNA) and p53 in a selected series of 30 OGCT, to evaluate their role in the prognostic evaluation of this tumour. Immunohistochemistry was performed on formalin‐fixed paraffin‐embedded sections. Results were compared with the DNA‐ploidy of the tumours (evaluated by image analysis) and with the follow‐up data of the patients.

Conclusions:  Loss of ERβ expression, high PCNA expression and aneuploidy, characterized a subgroup of OGCT with a worse outcome. The identification of a high‐risk subclass of OGCT may be of primary importance in addressing appropriate therapeutic strategies, offering the chance to prevent relapses and metastases by using adjunctive, specifically targetted, more aggressive therapies.
Bone marrow histopathology following cytoreductive therapy in chronic idiopathic myelofibrosis
Authors: Thiele J , Kvasnicka H M , Schmitt‐Graeff A , Diehl V
Published: December 2004

Aims: To analyse systematically therapy‐induced lesions of haematopoiesis in chronic idiopathic myelofibrosis (IMF).

Methods and results: A total of 759 sequential bone marrow (BM) biopsies (median interval 32 months) were performed in 261 patients with IMF. Besides a control group (symptomatic treatment), monotherapies included busulfan, hydroxyurea and interferon. In all therapy groups hypoplasia of varying degree was a frequent finding and often accompanied by a patchy distribution of haematopoiesis. Most conspicuous was gelatinous oedema showing a tendency to develop discrete reticulin fibrosis (scleroedema). Minimal to moderate maturation defects of megakaryopoiesis and erythroid precursors occurred, but overt myelodysplastic features were most prominent following hydroxyurea and busulfan therapy. Acceleration and blastic crisis were characterized by the appearance of immature and CD34+ progenitor cells. Concerning the dynamics of fibrosis, no differences were observed between controls and the various therapy groups. In 143 patients (55%) without or with little reticulin at onset, an increase in myelofibrosis was detectable that progressed to overt collagen fibrosis.

Conclusions: Therapy‐related bone marrow lesions in IMF comprise a strikingly variable spectrum that may include aplasia with scleroedema and a patchy distribution of myelodysplastic haematopoiesis associated with progressive myelofibrosis.
A CR1 polymorphism associated with constitutive erythrocyte CR1 levels affects binding to C4b but not C3b
Authors: Birmingham Daniel J. , Chen Wei , Liang Grace , Schmitt Holly C. , Gavit Katie , Nagaraja Haikady N.
Published: December 2004

The erythrocyte type one complement receptor (E‐CR1) mediates erythrocyte binding of complement‐opsonized immune complexes (IC), and helps protect against random deposition of circulating IC. Two linked CR1 polymorphisms occur in binding domains, at I643T and Q981H. In Caucasians, the variant alleles (643T, 981H) are associated with low constitutive E‐CR1 expression levels. This study was conducted to determine if these polymorphisms affect ligand binding, and if so, represent risk factors for the autoimmune IC disease, systemic lupus erythematosus (SLE). In an ELISA comparing relative ligand binding differences, E‐CR1 from individuals homozygous for the variant residues (643TT/981HH) exhibited greater binding to C4b, but not C3b, than homozygous wild‐type E‐CR1. Analysis of single‐binding domain CR1 constructs demonstrated that the 981H residue imparted this enhanced C4b binding. No differences were observed in the 981H allele frequency between Caucasian controls (0·170, n = 100) and SLE patients (0·130, n = 150, P = 0·133), or between African American controls (0·169, n = 71) and SLE patients (0·157, n = 67). In a subset of individuals assessed for CR1 size, excluding from this analysis those expressing at least one B allele revealed a trend for over‐representation of the 981H allele in Caucasian controls (0·231 frequency, n = 26) versus SLE patients (0·139, n = 83, P = 0·089), but again no difference between African American controls (0·188, n = 24) and SLE patients (0·191, n = 34). These data suggest that the 981H residue compensates for low constitutive expression of E‐CR1 in Caucasians by enhancing C4b binding. This may contribute protection against SLE.
B‐lymphocyte subpopulations are equally susceptible to Epstein–Barr virus infection, irrespective of immunoglobulin isotype expression
Authors: Ehlin‐Henriksson Barbro , Gordon John , Klein George
Published: December 2004

While Epstein–Barr virus (EBV) is known to establish latency in the memory B‐cell compartment, there is controversy as to whether the memory or the naïve B cell is the initial target for infection. Here we have explored the infectability of the B‐cell subsets contained in peripheral blood and tonsils, as distinguished by their surface expression of the immunoglobulin isotypes that help to define naïve and memory pools. First we show that both CD21 and major histocompatibility complex (MHC) class II molecules – respectively, the major receptor and co‐receptor for EBV on B cells – are expressed at similar levels on blood and tonsillar B cells, irrespective of surface immunoglobulin class, indicating that each of the subsets demonstrate an equal potential, at least for infection. Then, following in vitro infection of total tonsillar B cells, we found that the relative frequencies of immunoglobulin (Ig)M‐, IgG‐ and IgA‐positive cells containing EBV‐encoded Epstein–Barr virus nuclear antigen 5 (EBNA5) protein at 48 hr were similar to those of the starting population. However, IgD expression was uniformly decreased, probably as a consequence of cellular activation. These data indicate that recirculating B cells have both the potential for, and susceptibility to, initial infection by EBV, irrespective of the immunoglobulin isotype expressed.
Transmembrane T‐cell receptor peptides inhibit B‐ and natural killer‐cell function
Authors: Huynh Nghi T. , Ffrench Rosemary A. , Boadle Ross A. , Manolios Nicholas
Published: December 2004

A synthetic hydrophobic peptide (core peptide; CP) containing two positively charged amino acids, lysine and arginine was derived from the transmembrane sequence of the T‐cell receptor (TCR) α chain and has been shown to inhibit T‐cell‐mediated inflammation. In this study, we investigated the specificity of CP (10 μm) on lymphocyte function and found that it significantly inhibited interleukin‐2 production in T cells and natural killer cytotoxicity by 46–58% compared to positive control. CP had no effects on B‐cell proliferative responses when used at these concentrations; however, it suppressed B‐cell proliferation at higher concentrations (50 μm). Inhibition by CP was not the result of membrane pore formation or cytotoxicity when examined by trypan blue, propidium iodide staining or transmission electron microscopy. CP analogues, with both lysine and arginine replaced by neutral or negatively charged amino acids, or by randomly distributing charges in the peptide sequence, had no effect on lymphocyte function. These results suggest that peptide inhibition is affected by its structure and charge interactions, and may involve common signalling molecules in T, B and natural killer cells. The potential of the immuno‐inhibitory effects of CP as a novel anti‐inflammatory peptide in therapy should be further explored.
The CAG repeat polymorphism within the androgen receptor gene and maleness1
Authors: Zitzmann Michael , Nieschlag Eberhard
Published: December 2004

The androgen testosterone and its metabolite dihydrotestosterone exert their effects on gene expression and thus effect maleness via the androgen receptor (AR). A diverse range of clinical conditions starting with complete androgen insensitivity has been correlated with mutations in the AR. Subtle modulations of the transcriptional activity induced by the AR have also been observed and frequently assigned to a polyglutamine stretch of variable length within the N‐terminal domain of the receptor. This stretch is encoded by a variable number of CAG triplets in exon 1 of the AR gene located on the X chromosome. First observations of pathologically elongated AR CAG repeats in patients with X‐linked spino‐bulbar muscular atrophy showing marked hypoandrogenic traits were supplemented by partially conflicting findings of statistical significance also within the normal range of CAG repeat length: an involvement of prostate tissue, spermatogenesis, bone density, hair growth, cardiovascular risk factors and psychological factors has been demonstrated. The highly polymorphic nature of glutamine residues within the AR protein implies a subtle gradation of androgenicity among individuals within an environment of normal testosterone levels providing relevant ligand binding to ARs. This modulation of androgen effects may be small but continuously present during a man's lifetime and, hence, exerts effects that are measurable in many tissues as various degrees of androgenicity and represents a relevant effector of maleness. It remains to be elucidated whether these insights are important enough to become part of individually useful laboratory assessments.
Effects of NCX 4050, a new NO donor, in rabbit and human corpus cavernosum
Authors: Filippi S. , Crescioli C. , Vannelli G. B. , Fazzini A. , Natali A. , Riffaud J. P. , Maggi M. , Ledda F.
Published: December 2004

The effects of NCX 4050, a drug belonging to a new class of NO donors, was investigated in isolated preparations of human and rabbit corpus cavernosum (CC) and in human foetal corpora cavernosa (hfCC) smooth muscle cells. In strips of rabbit CC, NCX 4050 (0.001–100 μM) induced a concentration‐dependent relaxation which was influenced neither by Nw‐nitro‐l‐arginine‐methyl‐ester (l‐NAME; 100 μm) nor by endothelium deprivation. The NCX 4050‐induced relaxation was significantly reduced by the guanylate cyclase inhibitor 1H‐[1,2,4]‐oxadiazolo[4,3‐a]quinoxalin‐1‐one (ODQ; 1 μm) and enhanced by a specific phosphodiesterase 5 inhibitor, sildenafil (300 nm). Moreover, NCX 4050 (0.01–1 μm), induced a concentration‐dependent potentiation of the relaxant response induced by electrical field stimulation (EFS) in rabbit preparations pre‐treated with guanethidine and indomethacin. The relaxant effect of NCX 4050 was similar to that obtained by increasing concentrations (0.001–100 μm) of sodium nitroprusside (SNP) in either rabbit or human preparations. To further investigate the activity of NCX 4050 on human corpora cavernosa, we exposed cultured hfCC smooth muscle cells to increasing concentrations of NCX 4050 and SNP. We found that both compounds dose‐dependently reduced cell proliferation. The antiproliferative effect of all the concentration tested of NCX 4050 was completely blocked by ODQ (1 μm). These results suggest that in rabbit and human corpora cavernosa NCX 4050 acts by activating guanylate cyclase activity, induces smooth muscle relaxation and quiescence. Our results provide a rationale for a possible future use of NCX 4050 in the pharmacotherapy of erectile dysfunction linked to an impaired release of NO from the endothelium.
A novel animal model of thymic tumour: Development of epithelial thymoma in transgenic rats carrying human T lymphocyte virus type I pX gene
Authors: Kikuchi Kazunori , Ikeda Hitoshi , Tsuchikawa Takahiro , Tsuji Takahiro , Tanaka Satoshi , Fugo Kazunori , Sugaya Toshiaki , Tanaka Yuetsu , Tateno Masatoshi , Maruyama Naoki , Yoshiki Takashi
Published: December 2004

The pX region encodes a major product of human T lymphocyte virus type I (HTLV‐I) that has been implicated previously in tumour formation. To investigate the pathogenesis of pX gene in lymphoid tissues, we established a series of novel transgenic rats carrying the pX gene under the control of a rat lymphocyte‐specific protein tyrosine kinase (p56lck) proximal promoter.

The transgene was constructed with the −269 to +26 region of a rat p56lck proximal promoter and the pX cDNA, and was microinjected into fertilized ova of Fischer 344/jcl female rats. Six transgenic lines from 114 pups were established. Integration and expression of the transgene were detected by polymerase chain reaction (PCR) and Southern hybridization or by reverse transcriptase‐PCR, northern hybridization, and immunostaining.

 Thymic tumours with lethal expansion occurred in 4 of 6 transgenic lines. The tumour consisted of spindle shaped cells. Immunohistochemical and ultra‐structural analysis characterized the tumour cells to as epithelial cell type, and in the tumour arose in the medulla. Therefore, the tumour is classified into predominantly epithelial and spindle cell of medullary thymoma (type A of the new World Health Organization classification), as based on the human classification. Tumor occurrence increased in proportion to levels of the pX transcription in the thymus, for each line, and sex distinction was evident regarding rates related to tumour expansion. The transgenic rat model described here is suitable as a model for analysing tumorigenesis in epithelial thymoma occurring in humans.
Quality and sensory acceptance of fish sauce partially substituting sodium chloride or natural salt with potassium chloride during the fermentation process
Authors: Sanceda N. , Suzuki E. , Kurata T.
Published: December 2004

Fish sauce was prepared with sodium chloride or natural salt partially replaced by potassium chloride at three ratios, 90 : 10, 75 : 25 and 60 : 40. Volatile acids were collected by steam distillation under reduced pressure and measured. The sensory property of the products was evaluated. The amino acid content was also measured. Most of the volatile acids in all the samples with added KCl were higher than in the controls, suggesting a role for KCl in the formation of volatile acids in fish sauce manufacture. Sensory evaluation showed slight differences in odour between the samples with added KCl and the controls, but the differences did not affect the acceptability of the product. However, acceptance of taste terminated at a 75 : 25 NaCl or natural salt : KCl ratio. Almost all the amino acids in the control and in the fish sauces with added KCl were comparable to those of commercial fish sauce. Partial substitution of NaCl or natural salt with KCl up to a ratio of 75 : 25 seems feasible.
Population dynamics of the pipistrelle bat: effects of sex, age and winter weather on seasonal survival
Authors: Sendor Thomas , Simon Matthias
Published: December 2004

Life‐history theory assumes increased mortality at certain stages such as hibernation. However, seasonal variation of survival rates of hibernating mammals has rarely been estimated. In this study, apparent survival of pipistrelle bats (Pipistrellus pipistrellus) hibernating and performing summer swarming at a large hibernaculum (Marburg Castle, Hesse, Germany), was modelled using seasonal (summer/winter) capture–recapture data for the years 1996–2000. The spring survival interval includes the period of arousal at the end of hibernation and therefore validly measures survival associated with hibernation.

In five summers and four winters, 15 839 bats were captured and released (13 082 individuals) and 3403 recaptures recorded. Analysis was complicated by transience and trap‐dependence. Recapture rates varied seasonally and by group. The autumnal survival estimates were negatively biased due to transience effects that could not be taken into account.

Survival could be modelled using two age‐classes, with reduced first‐year juvenile survival. The age effect persisted over the first autumn and spring. There was virtually no evidence for sex‐specific survival rates; male and female survival were found to be almost equal. In the best‐fitting models, survival rates varied over time and differed among sexes and age‐classes by a constant amount. Between years, there was only a small variation in spring survival, which could not be explained by winter severity.

Adult spring survival was surprisingly high, averaging 0·892 (= 0·028). No evidence for increased mortality during hibernation could be found. This contradicted the expectation of reduced over‐winter survival due to depleted fat reserves at the end of hibernation. Thus, hibernation does apparently not entail a survival cost for the pipistrelle bat. Rough estimates of annual adult survival averaged 0·799 ( = 0·051), which considerably exceeds previous estimates; annual juvenile survival was estimated at 0·527 ( = 0·095). Hence, previous studies have substantially underestimated pipistrelle bat survival. Possible consequences of these findings for various aspects of life histories are discussed.
Teaching and learning about skills in minor surgery
Authors: Nestel Debra , Kneebone Roger , Kidd Jane
Published: December 2004

• The aim of this study was to assess the feasibility of a scenario‐based approach to learning minor surgery skills.

• After learning component technical skills for ellipse excision and wound closure, nurses were provided with an opportunity to integrate these skills with communication skills and contextual factors in a quasi‐clinical environment.

• Feasibility was assessed using observation of procedures and a group interview with participants, simulated patients and tutors.

• The scenario‐based approach to teaching and learning about technical and communication skills proved feasible and was valued by participants in this course on minor surgery.

• Although all participants expressed anxiety about integrating skills in the quasi‐clinical setting, they valued the opportunity to undergo a formative assessment prior to working in supervised settings with real patients.

• Learners valued highly the opportunity to reflect on their performance and to receive feedback on technical and communication skills.

• Future courses should include focused teaching on communication skills prior to the scenario‐based exercise.

• Limitations of the study centre on the small numbers of participants and the novelty of the course. Repeating the evaluations on a subsequent course will provide insight into the ways in which nurses acquire and integrate new skills.
Bridging the divide: a survey of nurses’ opinions regarding barriers to, and facilitators of, research utilization in the practice setting
Authors: Hutchinson Alison Margaret , Johnston Linda
Published: December 2004

Background.  Many researchers have explored the barriers to research uptake in order to overcome them and identify strategies to facilitate research utilization. However, the research–practice gap remains a persistent issue for the nursing profession.

Aims and objectives.  The aim of this study was to gain an understanding of perceived influences on nurses’ utilization of research, and explore what differences or commonalities exist between the findings of this research and those of studies that have been conducted in various countries during the past 10 years.

Design.  Nurses were surveyed to elicit their opinions regarding barriers to, and facilitators of, research utilization. The instrument comprised a 29‐item validated questionnaire, titled Barriers to Research Utilisation Scale (BARRIERS Scale), an eight‐item scale of facilitators, provision for respondents to record additional barriers and/or facilitators and a series of demographic questions.

Method.  The questionnaire was administered in 2001 to all nurses (n = 761) working at a major teaching hospital in Melbourne, Australia. A 45% response rate was achieved.

Results.  Greatest barriers to research utilization reported included time constraints, lack of awareness of available research literature, insufficient authority to change practice, inadequate skills in critical appraisal and lack of support for implementation of research findings. Greatest facilitators to research utilization reported included availability of more time to review and implement research findings, availability of more relevant research and colleague support.

Conclusion.  One of the most striking features of the findings of the present study is that perceptions of Australian nurses are remarkably consistent with reported perceptions of nurses in the US, UK and Northern Ireland during the past decade.

Relevance to clinical practice.  If the use of research evidence in practice results in better outcomes for our patients, this behoves us, as a profession, to address issues surrounding support for implementation of research findings, authority to change practice, time constraints and ability to critically appraise research with conviction and a sense of urgency.
Controlled clinical trial of two weight reducing diets in a NHS hospital dietetic outpatient clinic – a pilot study
Authors: Taylor F. C. , Irons L. J. , Finn P. , Summerbell C. D.
Published: December 2004

Background  Outpatient dietary weight reduction for obesity is unsatisfactory. The objective of this study was to compare the efficacy of an energy prescription diet with usual care (a healthy eating diet) in adult overweight patients referred to a NHS hospital dietetic outpatient clinic, in terms of weight change over 12 weeks.

Methods  Controlled clinical trial (systematic allocation).

Results  Of the 53 patients who attended their first appointment, 27 completed the trial. Mean weight loss (kg) after 12 weeks was 4.2 (sd 3.8) on the energy prescription diet (n = 16) and 6.0 (sd 2.8) on the healthy eating diet (n = 11).

Conclusions  Patients on a weight reducing diet based on energy prescription or healthy eating lost, on average, clinically significant amounts of body weight by 12 weeks. Mean weight loss was greater by about 50% in the energy prescription group and supports the development of a larger trial to estimate true effect.
Effectiveness of dietary advice given by community dietitians to men with elevated blood cholesterol in a clinical setting: a pilot study
Authors: Drummond S. , Kirk T. , Jackson J. , Hendry J. , Panton S. , Gray F.
Published: December 2004

Objective  To compare the effect of two types of dietary advice given by community dietitians on subsequent dietary intake in Scottish men, over 8 weeks.

Design  A parallel design intervention study was employed. Twenty‐five men with elevated blood cholesterol levels were randomly assigned to Group 1 (advice to reduce dietary fat only) or Group 2 (advice to reduce dietary fat and sugar).

Results  Neither group significantly reduced fat intakes, yet both groups self‐rated their fat intake as being lower at the end than at the start of the study. Group 2 reduced per cent energy from sugar and increased per cent energy from starch without significantly changing per cent energy from total carbohydrate. No significant change in blood cholesterol levels were observed.

Conclusions  Advice to reduce dietary fat was not effective in this group of subjects. Advice to reduce both fat and sugar resulted in a decrease in sugar intake only. Both groups wrongly rated their fat intake to be lower at the end of the study. This may be a barrier to further dietary advice.
Pharmacokinetic and pharmacodynamic properties of metomidate in turbot (Scophthalmus maximus) and halibut (Hippoglossus hippoglossus)
Authors: Hansen M. K. , Nymoen U. , Horsberg T. E.
Published: December 2004

Metomidate was administered to halibut (Hippoglossus hippoglossus) and turbot (Scophthalmus maximus) intravenously at a dose of 3 mg/kg bodyweight, as a bath treatment at a dose of 9 mg/L water for 5 min to study the disposition of metomidate, and as bath treatment (9 mg/L) for 10 min to study the absorption and effect of metomidate on respiration and balance/motor control. Additionally, turbot were given metomidate orally at a dose of 7 mg/kg. The studies were performed in seawater at a temperature of 10.3 ± 0.4 °C (halibut) and 18.0 ± 0.3 °C (turbot). Pharmacokinetic modeling of the data showed that metomidate had shorter elimination half‐life and higher plasma concentrations in turbot compared with halibut, both species displaying a rapid uptake, distribution and excretion. Following intravenous administration, the volumes of distribution at steady state (Vd(ss)) were 0.21 L/kg (halibut) and 0.44 L/kg (turbot). Plasma clearances (Cl) were 0.099 L/h·kg in halibut and 0.26 L/h·kg in turbot and the elimination half‐lives (t½λz) were calculated to be 5.8 h and 2.2 h in halibut and turbot, respectively. Mean residence times (MRT) were 2.2 h in halibut and 1.7 h in turbot. Following oral administration, the t½λz was 3.5 h in turbot. The maximum plasma concentration (Cmax) was 7.8 mg/L in turbot 1 h after administration. The oral bioavailability (F) was calculated to 100% in turbot. Following 5 min bath the maximum plasma concentrations (Cmax), which were observed immediately after end of the bath, were 9.5 mg/L and 13.3 mg/L in halibut and turbot, respectively. Metomidate rapidly immobilized the fish, with respiratory depression, reduced heart rate, and loss of balance/motor control within 1 min (mean). Recovery was slow, with resumed balance/motor control after 26.4 min. Opercular respiration movements were resumed more rapidly with a recorded mean of 1.7 min. Oral administration was demonstrated to be a way of immobilizing fish, for example in large aquariums, without exposing them to unwanted stress.
Increasing serum levels of IgM anti‐HCV are diagnostic of recurrent hepatitis C in liver transplant patients with ALT flares
Authors: Ciccorossi P. , Filipponi F. , Oliveri F. , Campani D. , Colombatto P. , Bonino F. , Campa M. , Maltinti G. , Mosca F. , Brunetto M. R.
Published: December 2004

Summary.  Recurrent hepatitis and acute rejection share common features which make difficult for diagnosis in liver transplant hepatitis C virus (HCV) positive patients. We studied the usefulness of quantitative monitoring of HCV RNA and immunoglobulin (Ig)M anti‐HCV in the differential diagnosis between recurrent hepatitis and acute rejection in 98 consecutive anti‐HCV positive liver transplant patients. Aminotransferase levels, serum HCV RNA and IgM anti‐HCV were measured at the time of transplantation and monthly thereafter. A liver biopsy (LB) was obtained when serum aminotransferase levels increased to twice or more than normal. During a mean follow‐up of 16 months 86 aminotransferase flares were observed. Histology was compatible with recurrent hepatitis C in 44 cases and with acute rejection in 28, doubtful in 14. The fluctuations of HCV RNA serum levels were not significantly different in the three groups. Serum IgM anti‐HCV levels increased (from negative to positive or with value variations ≥ 0.18) in 36 of 44 cases with recurrent hepatitis C at the time of alanine aminotransferase (ALT) flare. IgM anti‐HCV remained unchanged in all rejection cases (P < 0.001), but increased in 10 of 11 histologically doubtful cases that were diagnosed as hepatitis at the second LB. Increasing serum levels of IgM anti‐HCV at the time of ALT flares are significantly associated with recurrent hepatitis C in liver transplant patients. The quantitative monitoring of IgM anti‐HCV appears to be an additional diagnostic tool for distinguishing recurrent hepatitis C from acute graft rejection with a 100% specificity; 100% positive predictive value and 88.9% diagnostic accuracy.
Modulation of endothelial cell inflammatory integrins and stress markers with rh‐factor VIIa in patients with advanced chronic hepatitis C
Authors: Van Thiel D. H. , Anantharaju A. , Mindikoglu A. L. , Shah N. , Leone N. , Bejna J. , Tarasuk G. , Todo A. , Mobarhan S. , George M.
Published: December 2004

Summary. Individuals with chronic hepatitis C (CHC) progress to cirrhosis and hepatic cancer. Individuals with advanced CHC are coagulopathic and can manifest fibrinolysis. The coagulopathy is a consequence of hepatocytic dysfunction. The fibrinolysis represents a response to local endothelial cell injury, and is of a low‐grade. Based upon this hypothesis, the effect of the infusion of recombinant human factor VIIa (rh‐FVIIa) on endothelial cell inflammatory integrins and measures of endothelial stress were determined in 17 individuals with advanced CHC. Immediately prior to the infusion of rh‐FVIIa, the plasma levels of tissue factor (TF), Thrombomodulin (TM), human soluble ICAM‐1 (hs‐ICAM‐1), human soluble VCAM‐1 (hs‐VCAM‐1), human soluble L‐Selectin (hs‐L‐Selectin), the prothrombin time and the activated partial thromboplastin time were determined. The same parameters were assayed at 5, 10, 30, 120, 240 and 360 min after infusion. TF and TM levels were very high at baseline consistent with a vascular endothelial stress response. Similarly hs‐ICAM‐1, hs‐VCAM‐1 as well as L‐Selectin levels were increased. Thirty minutes after the infusion, a marked reduction in ICAM‐1 and VCAM‐1 and to a lesser degree L‐Selectin levels was observed. This reduction persisted for 360 min. No change in measures of fibrinolysis [plasminogen activator inhibitor‐1 (PAI‐1), total tissue factor pathway inhibitor (t‐TFPI), activated tissue factor pathway inhibitor (TFPIa), d‐dimers (DD), FSP and fibrinogen levels] occurred. In addition, no change in plasma Annexin‐V was observed. Based upon these data it can be concluded that: (1) rh‐FVIIa corrects the coagulopathy seen in advanced CHC; (2) reduces endothelial cell injury and/or stress as evidenced by the TF, TM, hs‐ICAM‐1 and hs‐VCAM‐1 levels in plasma; (3) these changes in coagulation occurred without inducing a propagated vascular thrombosis.
Predicting progression to cirrhosis in chronic hepatitis C virus infection
Authors: Freeman A. J. , Law M. G. , Kaldor J. M. , Dore G. J.
Published: December 2004

Summary. A systematic evaluation of published studies was undertaken to identify factors associated with accelerated fibrosis progression in patients with chronic hepatitis C virus (HCV) infection. An ecologic analysis was used to estimate relative risk (RR) of cirrhosis across four study methodologies: liver clinic series, post‐transfusion cohorts, community‐based studies and blood donor series. In each study category, the following factors were independently associated with disease progression: male sex (RR = 1.08); heavy alcohol consumption (RR = 1.61); elevated serum ALT levels (RR = 1.23) and histology demonstrating high‐grade necro‐inflammatory activity. After adjusting for these cofactors, older age at HCV infection and acquisition of HCV through blood transfusion were not implicated in influencing disease outcome. Although not able to be examined in this study,co‐infection with HIV, and to a lesser extent HBV, is also likely to result in worse outcomes for patients with chronic HCV infection. Virological factors such as HCV genotype, viral load and quasispecies diversity are less likely to be important. A Weibull distribution was used to model disease progression at a population level. The influence of cofactors on individual prognosis was examined and an algorithm to predict the risk of subsequently developing cirrhosis is presented.
Twice‐weekly administration of peginterferon‐α‐2b improves viral kinetics in patients with chronic hepatitis C genotype 1
Authors: Formann E. , Jessner W. , Bennett L. , Ferenci P.
Published: December 2004

Summary.  The decline in hepatitis C viral load on treatment with peginterferon‐α‐2b is not continuous. The aim of this study was to investigate whether twice weekly dosing of peginterferon‐α‐2b may improve viral kinetics. Ten interferon‐naïve patients with chronic hepatitis C (genotype 1a or b) were randomized to receive either 1.0 μg/kg peginterferon‐α‐2b once (group A) or twice weekly (group B) for 4 weeks. Viral load and serum concentrations of peginterferon‐α‐2b were measured. Peginterferon‐α‐2b reached maximal blood concentrations 24 h after the first dose, followed by a linear decline during the subsequent days. On the day before administration of the next dose, peginterferon‐α‐2b was undetectable in nine patients in group A (once weekly dosing). The same pattern was observed during the next 3 weeks of therapy. In group B (twice weekly dosing) peginterferon‐α‐2b was detectable at any given time point and higher than in group A (P between 0.01 and <0.0001). Viral load decreased in all patients within 2 days after the first dose of peginterferon‐α‐2b, but increased again on day 3. In group A, it further increased until day 7. A similar pattern was observed in the second week. In contrast, in group B, viral load decreased again on day 4 and remained lower until the end of the study (P < 0.001). To achieve continuous drug exposure and to improve initial viral clearance, peginterferon‐α‐2b has to be given at least two times weekly.
Distribution and diversity of rhizobia nodulating agroforestry legumes in soils from three continents in the tropics
Authors: Bala Abdullah , Murphy Phillip , Giller Ken E.
Published: December 2004

The natural rhizobial populations of Calliandra calothyrsus, Gliricidia sepium, Leucaena leucocephala and Sesbania sesban were assessed in soils from nine sites across tropical areas of three continents. The rhizobial population size varied from undetectable numbers to 1.8 × 104 cells/g of soil depending on the trap host and the soil. Calliandra calothyrsus was the most promiscuous legume, nodulating in eight soils, while S. sesban nodulated in only one of the soils. Polymerase chain reaction restriction fragment length polymorphism (PCR‐RFLP) analyses of the 16S rRNA gene and the internally transcribed spacer (ITS) region between the 16S and 23S rRNA genes were used to assess the diversity and relative abundance of rhizobia trapped from seven of the soils by C. calothyrsus, G. sepium and L. leucocephala. Representatives of the 16S rRNA RFLP groups were also subjected to sequence analysis of the first 950 base pairs of the 16S rRNA gene. Eighty ITS groups were obtained, with none of the ITS types being sampled in more than one soil. RFLP analysis of the 16S rRNA yielded 23 ‘species’ groups distributed among the Rhizobium, Mesorhizobium, Sinorhizobium and Agrobacterium branches of the rhizobial phylogenetic tree. The phylogeny of the isolates was independent of the site or host of isolation, with different rhizobial groups associated with each host across the soils from widely separated geographical regions. Although rhizobial populations in soils sampled from the centre of diversity of the host legumes were the most genetically diverse, soil acidity was highly correlated with the diversity of ITS types. Our results support the hypothesis that the success of these tree legumes in soils throughout the tropics is the result of their relative promiscuity (permissiveness) allowing nodulation with diverse indigenous rhizobial types.
Combining genetic markers and stable isotopes to reveal population connectivity and migration patterns in a Neotropical migrant, Wilson's warbler (Wilsonia pusilla)
Authors: Clegg Sonya M. , Kelly Jeffrey F. , Kimura Mari , Smith Thomas B.
Published: December 2004

We used results from the analysis of microsatellite DNA variation and hydrogen stable‐isotope ratios to characterize the population structure of a neotropical migrant passerine, the Wilson's warbler (Wilsonia pusilla). The resulting information was then used to infer migration patterns and population connectivity between breeding grounds in North America and overwintering areas in Mexico and Central America. The microsatellite data revealed genetic structure across the North American continent; populations in the west were found to significantly differ from the east. Minimal genetic structure was observed among western sites. The lack of isolation by distance and low variance inFSTvalues suggests that gene flow could play an ongoing role in limiting genetic differentiation among sites in the western part of the distribution. However, additional information including estimates of effective population size and the proximity of the population to equilibrium is required before the role of gene flow can be assessed fully. Analysis of isotope data showed a negative relationship between latitude and hydrogen isotope ratios in breeding ground individuals. There was a positive relationship between wintering ground latitude and hydrogen isotope ratios for individuals that were genetically western in origin. This is consistent with a leapfrog pattern of migration, in which genetically western birds from the northernmost breeding areas overwinter at the most southerly locations in Central America. Additionally, isotopic ratios of western birds suggest that coastal breeders overwinter in western Mexico, while western birds from further inland and at high elevations overwinter in eastern Mexico. Using information from both genetic an isotopic approaches will probably be useful for identifying patterns of migration and population connectivity between breeding and overwintering areas, both important issues for conservation efforts, and may also contribute to investigation of the evolution of migration.
Low and homogeneous copy number of plasmid‐borne symbiont genes affecting host nutrition in Buchnera aphidicola of the aphid Uroleucon ambrosiae
Authors: Plague Gordon R. , Dale Colin , Moran Nancy A.
Published: December 2004

The bacterial endosymbiont of aphids, Buchnera aphidicola, often provides amino acids to its hosts. Plasmid amplification of leucine (leuABCD) and tryptophan (trpEG) biosynthesis genes may be a mechanism by which some Buchnera over‐produce these nutrients. We used quantitative polymerase chain reaction to assess the leuABCD/trpEG copy variability within Uroleucon ambrosiae, an aphid with a wide diet breadth and range. Both leuABCD and trpEG abundances are: (i) similar for aphids across 15 populations, and (ii) low compared to Buchnera from other aphid species (particularly trpEG). Consequently, the plasmid location of trpEG combined with Buchnera's chromosomal polyploidy may functionally limit, rather than increase, tryptophan production within Uroleucon ambrosiae.
A test for deviation from island‐model population structure
Authors: Porter Adam H.
Published: December 2004

The neutral island model forms the basis for several estimation models that relate patterns of genetic structure to microevolutionary processes. Estimates of gene flow are often based on this model and may be biased when the model's assumptions are violated. An appropriate test for violations is to compare FST scores for individual loci to a null distribution based on the average FST taken over multiple loci. A parametric bootstrap method is described here based on Wright's β‐distribution to generate null distributions of FST for each locus. These null distributions account for error introduced by sampling populations, individuals and loci, and also biological sources of error, including variable alleles/locus and inbreeding. Confidence limits can be obtained directly from these distributions. Significant deviations from the island model may be the result of selection, deviations from the island model's migration pattern, nonequilibrium conditions, or other deviations from island‐model assumptions. Only strong biases are likely to be detected because of the inherently large sampling variation of FST. Nevertheless, a coefficient, Nb, describing bias in the spread of the β‐distribution in units comparable to the gene flow parameter, Nm, can be obtained for each locus. In samples from populations of the butterfly Coenonympha tullia, the loci Idh‐1, Mdh‐1, Pgi and Pgm showed significantly lower FST than expected.
Molecular phylogeography of the Amazonian Chagas disease vectors Rhodnius prolixus and R. robustus
Authors: Monteiro Fernando A. , Barrett Toby V. , Fitzpatrick Sinead , Cordon‐Rosales Celia , Feliciangeli Dora , Beard Charles B.
Published: December 2004

The phylogeographical structure of the closely related species Rhodnius prolixus and R. robustus is presented based on a 663‐base pair (bp) fragment of the mitochondrial cytochrome b gene. Twenty haplotypes were recovered from 84 samples examined, representing 26 populations from seven Latin American countries. The resulting phylogenetic tree is composed of five major reciprocally monophyletic clades, one representing R. prolixus and four representing R. robustus. While R. prolixus is a very homogeneous assemblage, R. robustus has deeper clades and is paraphyletic, with the clade comprising R. robustus from Venezuela (Orinoco region) more closely related to the R. prolixus clade than to the other R. robustus populations from the Amazon region. The R. robustus paraphyly was supported further by the analysis of a nuclear gene (D2 region of the 28S RNA) for a subset of specimens. The data support the view that R. robustus represents a species complex. Levels of sequence divergence between clades within each region are compatible with a Pleistocene origin. Nucleotide diversity (π) for all R. prolixus populations was extremely low (0.0008), suggesting that this species went through a recent bottleneck, and was subsequently dispersed by man.
Patterns of nuclear DNA degeneration over time — a case study in historic teeth samples
Authors: Wandeler P. , Smith S. , Morin P. A. , Pettifor R. A. , Funk S. M.
Published: December 2004

The amount of nuclear DNA extracted from teeth of 279 individual red fox Vulpes vulpes collected over a period spanning the last three decades was determined by quantitative polymerase chain reaction (PCR). Although teeth were autoclaved during initial collection, 73.8% of extracts contained sufficient DNA concentration (> 5 pg/µL) suitable for reliable microsatellite genotyping but the quantity of nuclear DNA decayed significantly over time in a nonlinear pattern. The success of PCR amplification across four examined canine microsatellites over time was dependent on fragment size. By including data from two different tests for human contamination and from frequencies of allelic dropout and false alleles, the methodological constraints of population genetic studies using microsatellite loci amplified from historic DNA are discussed.
Matrilineal genetic structure within and among populations of the cooperatively breeding common marmoset,Callithrix jacchus
Authors: Faulkes C. G. , Arruda M. F. , Monteiro Da Cruz M. A. O.
Published: December 2004

Common marmosets are members of the family Callitrichidae, South American primates characterized by highly social group living and cooperative breeding. In this study we analysed 1112 base pairs (bp) of the mitochondrial control region in 59Callithrix jacchusindividuals, sampled mainly from two geographically distinct field sites in N.E. Brazil. Analysis of molecular variation revealed a highly significant genetic structuring of haplotypes between social groups and between populations. Examination of matrilineal genetic structure within social groups revealed that seven of nine recorded breeding pairs were from different maternal lineages, indicating assortative mating and outbreeding. In addition to the breeders, at least six of 10 groups contained adult individuals from different matrilines, with five haplotypes present in one social group of nine animals. Groups of mixed lineages raise questions about potential reproductive conflicts of interest, and the extent of kin‐selected altruism in the evolution and maintenance of cooperative breeding in this species.
Clines and adaptive evolution in the methuselah gene region in Drosophila melanogaster
Authors: Duvernell David D. , Schmidt Paul S. , Eanes Walter F.
Published: December 2004

In an effort to characterize further the patterns of selection and adaptive evolution at the methuselah locus in Drosophila species, we extended an analysis of geographical variation to include single nucleotide polymorphisms (SNPs) in adjacent genes on either side of the mth locus, and examined the molecular variation in a neighbouring methuselah paralogue (mth2). An analysis of 13 SNPs spanning a region of nearly 19 kilobases surrounding the mth locus demonstrated that a clinal pattern associated with the most common mth haplotype does not extend to adjacent gene loci, providing compelling evidence that the clinal pattern results from selection on as yet unidentified sites associated with the functional mth locus. mth2 exhibited a significant pattern of adaptive divergence among D. melanogaster, D. simulans and D. yakuba similar to that seen at mth. However, Ka : Ks ratios indicate a difference in levels of functional constraint at the two methuselah, loci with mth2 exhibiting a five‐ to six‐fold reduction in levels of amino acid divergence relative to mth.
The distribution of the ancestral haplotype in finite stepping‐stone models with population expansion
Authors: Satta Y. , Takahata N.
Published: December 2004

Recent extensive analyses of human DNA polymorphism reveal that the ancestral haplotype at various genetic loci occurs almost exclusively in African samples. We develop a coalescence‐based simulation method in stepping‐stone models with population expansion and examine the probability (PA) that the ancestral haplotype is found in African samples and the probability (QA) that the most recent common ancestor of sampled genes occurs in Africa. These probabilities and other summary statistics are used to infer the human demographic history. It is shown that the high observed PA value cannot be explained simply by sampling bias. Rather, it suggests that the African population has been more strongly subdivided and isolated from each other than the non‐African population and that there must have been some African populations which were not directly involved in the Out‐of‐Africa expansion in the late Pleistocene.