bluuebunny/crossref_metadata_2025_split huggingface dataset:
Demographic expansion of parasitic nematodes of livestock based on mitochondrial DNA regions that conflict with the infinite‐sites model
Authors: Mes T. H. M. 
Published: May 2003

AbstractMitochondrial ND4 sequences of populations of four species of parasitic nematodes of livestock were subjected to demographic analyses. Deviation from selective neutrality was detectable using the frequency spectrum of segregating sites and highly negative neutrality statistics. However, the mitochondrial data sets do not comply with the infinite‐sites model that underlies these tests, and as a consequence, it was not established whether these features are solely a result of population expansion, or whether aspects of the molecular evolution of these mitochondrial regions are also involved. Coalescent analyses based on Fu's Fs neutrality test, which incorporated estimates of rate heterogeneity, the transition–transversion ratio and nucleotide bias, as well as analyses that are fairly robust to deviations from the infinite‐sites model supported population expansion. Also analyses that do not depend on the infinite‐sites model suggested historical population expansion of these nematodes. The very similar time since expansion, the absence of signatures of positive selection in ND4 and the logical association with human demography imply that selective sweeps of mitochondrial variants are less probable, and that expansion is the most likely scenario for the parasitic nematodes of livestock. The methods used to characterize the expansion have different assumptions and emphasize different aspects of expansions. The resulting restrictions on the interpretation of expansions are outlined.
Evidence for interspecies transmission of viruses in natural populations of filamentous fungi in the genus Cryphonectria
Authors: Liu Y.‐C. , Linder‐Basso D. , Hillman B. I. , Kaneko S. , Milgroom M. G. 
Published: May 2003

AbstractInterspecies transmission is a significant evolutionary event that has allowed a variety of pathogens to invade new host species. We investigated interspecies transmission of viruses between the chestnut blight fungus, Cryphonectria parasitica, and a sympatric unidentified Cryphonectria species in Japan. Two isolates of Cryphonectria sp. were found to contain Cryphonectria hypovirus 1 (CHV‐1), which has been typically found in C. parasitica. Three lines of evidence support the hypothesis of interspecies transmission of CHV‐1. First, host species occur sympatrically and therefore have the opportunity to come into physical contact. Second, we transmitted CHV‐1 between species experimentally in the laboratory. Third, phylogenetic analysis of 476 bp of the ORF B region of CHV‐1 showed that sequences from Cryphonectria sp. were more closely related to those from C. parasitica than to each other. Local geographical subdivision of virus sequences from both host species argues against the alternative hypothesis of independent evolution of CHV‐1 since speciation of their hosts. Based on these findings, we rule out the hypotheses that CHV‐1 diverged from viruses in a common ancestor of the hosts, or that ancestral polymorphisms in CHV‐1 persisted in the two host taxa. Estimating the direction and frequency of interspecies transmission in nature will require more extensive samples of CHV‐1 from both host species.
Reliable microsatellite genotyping of the Eurasian badger (Meles meles) using faecal DNA
Authors: Frantz A. C. , Pope L. C. , Carpenter P. J. , Roper T. J. , Wilson G. J. , Delahay R. J. , Burke T. 
Published: May 2003

AbstractThe potential link between badgers and bovine tuberculosis has made it vital to develop accurate techniques to census badgers. Here we investigate the potential of using genetic profiles obtained from faecal DNA as a basis for population size estimation. After trialling several methods we obtained a high amplification success rate (89%) by storing faeces in 70% ethanol and using the guanidine thiocyanate/silica method for extraction. Using 70% ethanol as a storage agent had the advantage of it being an antiseptic. In order to obtain reliable genotypes with fewer amplification reactions than the standard multiple‐tubes approach, we devised a comparative approach in which genetic profiles were compared and replication directed at similar, but not identical, genotypes. This modified method achieved a reduction in polymerase chain reactions comparable with the maximum‐likelihood model when just using reliability criteria, and was slightly better when using reliability criteria with the additional proviso that alleles must be observed twice to be considered reliable. Our comparative approach would be best suited for studies that include multiple faeces from each individual. We utilized our approach in a well‐studied population of badgers from which individuals had been sampled and reliable genotypes obtained. In a study of 53 faeces sampled from three social groups over 10 days, we found that direct enumeration could not be used to estimate population size, but that the application of mark–recapture models has the potential to provide more accurate results.
The practice of antenatal care: comparing four study sites in different parts of the world participating in the WHO Antenatal Care Randomised Controlled Trial
Authors: Piaggio G. , Ba’aqeel H. , Bergsjø P. , Carroli G. , Farnot U. , Lumbiganon P. , Pinol A. , Villar J. 
Published: May 2003

In the preparation of a randomised controlled trial to evaluate a new programme of antenatal care (ANC) in different parts of the world, we conducted a baseline survey of the ANC procedures in all 53 clinics participating in the trial. There were two components of this survey: (1) description of clinic characteristics and services offered: the staff of each clinic was interviewed and direct observation was made by field supervisors, and (2) the actual use of services by pregnant women attending these clinics: we reviewed a random sample of 2913 clinical histories.  The clinical units surveyed were offering most of the activities, screening, laboratory tests and interventions recommended as effective according to the Cochrane Pregnancy and Childbirth Database (PCD), although some of these were not available in some sites. On the other hand, some tests and interventions that are considered not effective according to these criteria are reportedly offered. There was a difference across sites in the availability and offer to low‐risk women of vaginal examination, evaluation of pelvic size, dental examination, external version for breech presentation and formal risk score classification, and a notable difference in the type of principal provider of ANC. There was a large variation in the actual use of screening and laboratory tests and interventions that should be offered to all women according to Cochrane PCD criteria: some of these are simply not available in a site; others are available, but only a fraction of women attending the clinics are receiving them. The participating sites all purport to follow the traditional ‘Western’ schedule for ANC, but in three sites we found that a high percentage of women initiate their ANC after the first trimester, and therefore do not have either the recommended minimum number of visits during pregnancy or the minimum first trimester evaluation. It is concluded that the variability and heterogeneity of ANC services provided in the four study sites are disturbing to the profession and cast doubts on the rationale of routine ANC.
Managing data for a randomised controlled clinical trial: experience from the WHO Antenatal Care Trial
Authors: Pinol A. , Bergel E. , Chaisiri K. , Diaz E. , Gandeh M. 
Published: May 2003

The World Health Organisation, in collaboration with four developing countries, is conducting a randomised controlled clinical trial to evaluate a new programme of antenatal care. In a city or region in Argentina, Cuba, Saudi Arabia and Thailand, 53 clinical units were randomly allocated to provide either the new programme or the programme currently in use. This paper describes the organisation of the data management system used to collect the data.  Each woman participating in the trial is uniquely identified, and information such as her name, address and expected delivery date is recorded in the trial ‘subject number list’. If the clinic belongs to the intervention group, information about the woman's eligibility is recorded on the classification form. Details of the outcome of the pregnancy are indicated on two additional case report forms: the antenatal hospital admission form and the summary form. When forms are completed by the investigators, they are submitted to the country data coordinating centre (CDCC).  The CDCCs are responsible for the processing of the country study forms. This includes verification of the batch of forms, data capture into computer files, data verification, data validation, production of query sheets for data problems, maintenance and updating of study master files. All operations on data such as additions or modifications are performed using transaction processing. At monthly intervals, recruitment reports and transaction files are sent to the trial coordinating centre in Geneva. All transaction files are processed to accumulate data on the trial's consolidated master files. A monthly report including number of women recruited in the trial, adverse events reported by the countries, recruitment charts by clinic and analyses on eligible women in the intervention group is prepared and submitted to the data safety and monitoring committee.  A workshop was organised in 1995, before the start of the trial, to introduce the data management system to the four participating countries. Annual site visits were made to each CDCC to monitor progress. Additional visits were made when major or critical problems could not be solved by the CDCC. At the closure of data collection, a visit is made to review and assess all data management procedures including form filling, maintenance of registers, computer files, query sheets, data modifications. In addition, final cleaning of the data is performed, and an analysis file is produced for inclusion in the centralised trial analyses and in the country‐specific analyses.  Based on the experience gained in this trial, the decentralised data management model can be advocated only if CDCCs that will be involved in the trial are already in place with competent and experienced staff. Uniformity of the data management system and of standard operating procedures across countries is also a crucial issue for the effective management of the data collection phase.
The WHO Antenatal Care Randomised Controlled Trial: rationale and study design
Authors: Villar J. , Bakketeig L. , Donner A. , Al‐Mazrou Y. , Ba’aqeel H. , Belizán J.M. , Carroli G. , Farnot U. , Lumbiganon P. , Piaggio G. , Berendes H. 
Published: May 2003

The World Health Organisation and collaborating institutions in developing countries are conducting a multicentre randomised controlled trial to evaluate a new antenatal care (ANC) programme, consisting of tests, clinical procedures and follow‐up actions scientifically demonstrated to be effective in improving maternal and newborn outcomes. These activities are distributed, for practical reasons, over four visits during the course of pregnancy and are aimed at achieving predetermined goals. The study is taking place in four countries, Argentina, Cuba, Saudi Arabia and Thailand. Recruitment of study subjects started on 1 May 1996. All 53 ANC clinical units had been enrolled by December 1996. Clinics in each country were randomly allocated (cluster randomisation) to provide either the new programme or the traditional programme currently in use. Approximately 24 000 women presenting for ANC at these clinics over an average period of 18 months will have been recruited. As women attending the control clinics receive the ‘best standard treatment’ as currently offered in these clinics, individual informed consent is requested only from women attending the intervention clinics. Authorities of the corresponding health districts and all participating clinics have provided written institutional informed consent before randomisation.  The primary outcome of the trial in relation to maternal conditions is the rate of a morbidity indicator index, defined as the presence of at least one of the following conditions for which ANC is relevant: (a) pre‐eclampsia or eclampsia during pregnancy or within 24 h of delivery; (b) postpartum anaemia (haemoglobin < 90 g/L); or (c) severe urinary tract infection/pyelonephritis, defined as an episode requiring antibiotic treatment and/or hospitalisation. The primary fetal outcome is the rate of low birthweight (< 2500 g). Adverse maternal and fetal outcomes are expected for ≈ 10% of the control group. Several maternal and perinatal secondary outcomes are also considered. A comprehensive cost‐effective‐ness analysis and women's and providers’ satisfaction evaluation are performed concurrently with the trial. Health‐care programmes should be rigorously evaluated by randomised controlled trials, which are feasible in developing countries and should be conducted before introducing new treatments or health interventions.
Prenatal and perinatal antecedents of febrile convulsions and afebrile seizures: data from a national cohort study
Authors: Greenwood Rosemary , Golding Jean , Ross Euan , Verity Chris 
Published: May 2003

The assumption is often made that brain damage during the perinatal period is likely to result in neurological abnormalities such as epilepsy and cerebral palsy. However, there has been accumulating evidence that cerebral palsy is rarely, if ever, a result of intrapartum events, but few studies of other neurological abnormalities have been undertaken.  We analysed data on 16 163 children from the 1970 British national cohort study and followed to age 10, focusing on the 378 who developed febrile convulsions (FCs) and 63 children with idiopathic afebrile seizures (IAS). Children with IAS were significantly more likely not to have been breast fed (P < 0.001), and this was independent of features such as birthweight and maternal disorder. A similar finding was apparent for FCs (P < 0.05). Although children with low birthweight were at increased risk of both conditions, there was no association with maternal smoking in pregnancy. No associations were found between indications of fetal distress during labour and later febrile convulsions or afebrile seizures. There was no evidence that intervention during labour would have improved these outcomes. However, associations were found with abnormalities earlier in pregnancy, suggesting a prenatal rather than an intrapartum aetiology.
Minimal residual marrow disease: Detection and significance of isolated tumour cells in bone marrow
Authors: Iorgulescu Dragos G. , Kiroff George K. 
Published: May 2003

Background: Detection of malignant cells in bone marrow and peripheral blood of patients with solid tumours at the time of surgery is increasingly emerging as a prognostic factor for disease progression and a way of monitoring adjuvant therapies. Furthermore, isolation and characterization of these cells provide insight into the early metastatic process, with potential therapeutic implications. This article reviews the current knowledge about the clinical significance of minimal residual marrow disease (MRMD) and its methods of detection, outlining some of their specific technical problems. Methods: A comprehensive review of articles cited in the largest medical databases was conducted. Results: The sensitivity of the methods of detecting MRMD has improved substantially in the past decade, resulting in higher detection rates. In many solid tumours MRMD has been found to correlate with disease‐free and overall survival; however, the importance of this as an independent prognostic variable remains contentious. Conclusions: There is a need for a standardized approach to the detection of these cells before they become integrated into the current staging systems. The challenge remains to establish which of these tumour cells have the capacity to progress and develop metastatic disease, what are the early genetic and molecular mechanisms underlying this process and to apply novel, better targeted therapies against them.
Fine‐needle aspiration cytology of parotid tumours: Is it useful?
Authors: Hee Christopher G. Que , Perry Christopher F. 
Published: May 2003

Background: The efficacy of fine‐needle aspiration cytology (FNAC) in the diagnosis of parotid tumours remains a controversial subject. Studies within small departments utilizing experienced pathologists have shown FNAC to have high sensitivity and specificity for parotid tumours. The present study was performed to assess the accuracy and utility of FNAC of parotid tumours within a teaching hospital environment. Methods: One hundred and sixty‐nine patients underwent both FNAC and subsequent surgery to the parotid between 1995 and 1999. The results of the FNAC were compared to the histopathological diagnosis obtained from the surgical specimen. Results: Fine‐needle aspiration cytology had an overall accuracy of 56%. Approximately 10% of the FNAC results were non‐diagnostic. The sensitivity and specificity for the following diagnoses were, respectively: benign 86% and 61%; malignant 57% and 100%; pleomorphic adenoma 78% and 95%; squamous cell carcinoma 52% and 99%; mucoepidermoid carcinoma 14% and 99% and adenocarcinoma 20% and 100%. Six non‐neoplastic conditions were misdiagnosed and all six patients underwent surgery. Conclusions: Fine‐needle aspiration cytology was found to be highly specific for malignancy but its sensitivity for malignancy was poor. The results show that although FNAC is relatively inexpensive and minimally invasive, it cannot be relied upon to provide an accurate tissue diagnosis, may fail to identify malignancy and does not prevent patients undergoing surgery for non‐neoplastic conditions.
Long‐term prognosis of femoropopliteal bypass: An analysis of 349 consecutive revascularizations
Authors: Lau Hung , Cheng Stephen W. K. 
Published: May 2003

Background: Femoropopliteal bypass is the commonest procedure for lower limb revascularization. The aim of the present study was to determine the long‐term outcomes of femoropopliteal bypass and evaluate the prognostic significance of various clinical factors on the long‐term results. Methods: From 1976 to 1998, 349 consecutive primary femoropopliteal bypass operations were performed on 314 patients at the University of Hong Kong Medical Centre. Indications for operation included claudication (n = 85) and limb‐threatening ischaemia (n = 264). Univariate and multivariate analyses of 14 clinical variables were undertaken to identify significant prognostic factors affecting the graft patency, limb salvage and patient survival rates. Results: The overall primary patency rates of femoropopliteal bypass were 88%, 79% and 76% at 1, 3 and 5 years, respectively. Type of graft material and age of patient were independent prognostic factors of graft patency. The cumulative limb salvage rates were 90%, 86% and 86% at 1, 3 and 5 years, respectively. No clinical factor was found to be predictive of ultimate limb loss. The overall survival rates were 89%, 85% and 78% at 1, 3 and 5 years, respectively. Coronary artery disease was the main cause of late death. Gender and indication for operation were the significant predictive factors of long‐term survival. Conclusions: Femoropopliteal bypass using reversed long saphenous vein provided the most durable long‐term patency. Autologous saphenous vein should be the choice of vascular conduit if available. Male gender and limb‐threatening ischaemia were associated with a poor survival.
Nephron‐sparing surgery for small incidental renal cell carcinoma
Authors: Sullivan Mark , Frydenberg Mark 
Published: May 2003

Background: Nephron‐sparing surgery is currently an accepted treatment for renal cell carcinomas in patients with bilateral tumours, solitary kidneys and when overall renal function is impaired or at risk from medical disease. Its role in patients with a normal contralateral kidney remains controversial. Methods: The authors’ experience in 23 patients undergoing partial nephrectomy for small peripheral lesions between 1995 and 2000 is reported here. Results: Twenty‐three patients (13 men and 10 women) with a mean age of 56 years underwent partial nephrectomy. All but three of these patients had a normal contralateral kidney. Mean operating time was 141 min with a mean reduction of haemoglobin of 28 g/dL. Three patients required transfusion. Serum creatinine did not change significantly between preoperative and postoperative values. Two JJ stents were placed prophylactically during surgery to minimize urinary leak. There were no intraoperative or early postoperative deaths and at mean follow up of 16 months there was no evidence of recurrent tumour in 23 patients. Seventeen per cent of lesions removed were benign. Conclusions: Partial nephrectomy for small peripheral lesions is a safe procedure with low morbidity. No definite recurrences are evident at an early stage of follow up, although longer review (probably more than 10 years) will be required to assess cancer‐specific survival following this procedure.
Ruptured abdominal aortic aneurysms: Clinical presentation in Auckland 1993–1997
Authors: Rose Johanna , Civil Ian , Koelmeyer Timothy , Haydock David , Adams Dave 
Published: May 2003

Background: Rupture of an abdominal aortic aneurysm (RAAA) carries a reported mortality rate in the range of 32–95%. Survival requires prompt diagnosis and surgical management. The presenting features, however, are varied, often insidious and potentially misleading with Osler noting nearly 100 years ago that a correct premortem diagnosis was achieved in only 33% of cases. The present study aims to review our present accuracy in diagnosing this condition and outline demographic and presenting features of patients with RAAA. Methods: A review was undertaken of hospital and Coroner’s files of all patients residing in the Auckland Coronial region who had RAAA between 1 January 1993 and 31 December 1997. Results: Three hundred and twenty‐nine cases of RAAA were identified, and they occurred most commonly in the 8th decade. The male:female ratio was 3:1 and at least 73% of patients were Caucasian. The overall mortality was 71%. Nearly half underwent surgery and the hospital averaged mortality rate was 46%. No patient survived without surgery. Classic presenting features of RAAA were absent in many cases. Abdominal pain, back pain and a palpable mass occurred in only 49%, 36% and 18% of patients, respectively. Other common presenting symptoms included vomiting, general malaise and pelvic or hip pain. Forty‐three patients (16%) were initially misdiagnosed. Conclusions: Although our ability to correctly diagnose a RAAA has improved since Osler’s time, the initial misdiagnosis rate of 16% leaves no room for complacency. Ruptured abdominal aortic aneurysms must be included in the differential diagnosis of any patient over the age of 55 years who presents with shock, even if the pain is non‐specific or atypical.