bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cost analysis of video-assisted thoracic surgeryversusthoracotomy: critical review
Authors: Van Schil P. 
Published: October 2003

Cost containment has become an important issue in thoracic surgery. Applying the principles of evidence-based medicine a literature search was performed to determine whether video-assisted thoracic surgery (VATS) has an advantage over thoracotomy concerning total cost.Only eight studies specifically looked at cost; all but one were retrospective. Lung biopsy by VATS yielded higher operating room costs compared with limited thoracotomy. The cost of VATS wedge resection of lung nodules was competitive with open techniques. In a prospective study regarding the treatment of pneumothorax by VATS, no advantages were demonstrated compared with axillary minithoracotomy. In two retrospective studies the total economic cost of VATS was lower but not all relevant factors were considered. Lung volume reduction surgery by VATS had a lower total inpatient cost compared with sternotomy but no specific details were provided. Finally, VATS treatment of lung cancer yielded conflicting results regarding total hospital charges.From these studies it is clear that video-assisted thoracic surgery has a higher initial cost. Whether this is offset by a more rapid discharge remains to be proven. There is a definite need for high-quality prospective randomised studies.
Angiotensin-converting enzyme genotype and the ventilatory responseto exertional hypoxia
Authors: Patel S. , Woods D.R. , Macleod N.J. , Brown A. , Patel K.R. , Montgomery H.E. , Peacock A.J. 
Published: October 2003

The “insertion” (I) rather than “deletion” (D) variant of the human angiotensin-converting enzyme (ACE) gene is associated with both lower tissue ACE activity and elite performance at high altitude. Three genotypes, II, ID and DD, are thus represented in the population. The authors examined whether an improved ventilatory response to hypoxic exercise may contribute to this effect.Subjects (n=60; 37 male, mean±sem age 23.6±0.6 yrs, 14 II, 30 ID, 16 DD) underwent incremental cardiopulmonary exercise testing to establish maximal oxygen uptake and ventilatory threshold (VT). Four hours later, subjects exercised for 6 mins at 50% of the workload at VT. The protocol was repeated 15 mins later while breathing 12.5±0.5% oxygen in nitrogen.All subject characteristics were independent of genotype, as were data during normoxic exercise. However, the hypoxia-induced rise in minute ventilation was significantly greater among those of II genotype (39.6±4.1%versus27.9±2.0%versus28.4±2.2% for IIversusIDversusDD, respectively). These data are supported by a significantly greater decrease in end tidal carbon dioxide (consistent with an increase in alveolar ventilation) among those homozygous for the I allele (II −18.7±1.3%, ID −15.7±0.4%, DD −15.1%±1.1).The ventilatory response to hypoxic exercise is influenced by angiotensin-converting enzyme genotype. Potential implications concern high altitude performance and the pathogenesis and management of hypoxic lung disease.
Health consequences associated with frequent wheezing in adolescents without asthma diagnosis
Authors: Yeatts K. , Johnston Davis K. , Peden D. , Shy C. 
Published: October 2003

Using questions from the International Study of Asthma and Allergies in Childhood, this study evaluated the association between undiagnosed frequent wheezing and health consequences in adolescents.The North Carolina School Asthma Survey provided self-reported questionnaire data on respiratory health from 122,829 children aged 12–14 yrs. The frequency of health consequences were compared among undiagnosed frequent wheezers, diagnosed asthmatics, and children with no wheezing symptoms or diagnosed asthma.The odds of wheezing-related sleep disturbances, limited activities, and missed school were higher among undiagnosed frequent wheezers, relative to diagnosed asthmatics. The frequency of emergency room visits and hospitalisations did not differ substantially between the undiagnosed wheezing and diagnosed asthma groups, though the undiagnosed group was less likely to have visited a physician for wheezing in the past year.Children with frequent wheezing symptoms but no asthma diagnosis experience substantial illness-related morbidity similar to that of diagnosed asthmatics. Undiagnosed frequent wheezers require more recognition from primary care physicians and need active disease management to reduce health consequences.
Effect of age and asthma duration upon elastase and α1-antitrypsin levels in adult asthmatics
Authors: Vignola A.M. , Bonanno A. , Profita M. , Riccobono L. , Scichilone N. , Spatafora M. , Bousquet J. , Bonsignore G. , Bellia V. 
Published: October 2003

In asthmatic subjects an imbalance between elastase and α1‐antitrypsin (α1‐PI) exists. This study aims to evaluate whether ageingper seaffects the levels of elastase.Both young and elderly asthmatics with comparable severity and duration of disease, as well as young and elderly healthy subjects, underwent an induced sputum procedure to measure levels of elastase and α1‐PI.The percentage of sputum neutrophils and eosinophils was higher in young and elderly asthmatics than in young and elderly controls. The levels of both total and active elastase were significantly higher in young and elderly asthmatics than in young and elderly controls, and directly correlated with the percentage of neutrophils. In addition, in both young and elderly asthmatics the levels of total and active elastase were negatively correlated with forced expiratory volume in one second values, but positively correlated with the duration of the disease.This study indicates that ageingper sedoes not necessarily lead to a progressive elastase/α1‐antitrypsin imbalance in asthma, and suggests that an important variable in the development of airway remodelling in both young and elderly asthmatics is represented by the duration of the disease.
The prevention of occupational asthma
Authors: Cullinan P. , Tarlo S. , Nemery B. 
Published: October 2003

There is sufficient understanding of the causation of occupational asthma for preventive action to be appropriate. To date, attempts appear to have been largely unsuccessful and this appears to be largely due to nonscientific/technical obstacles. These include the fragmented nature of the disease, its low public and industrial profile, and its comparative rarity in single workplaces. Nonetheless the disease has high individual and societal costs.Prevention strategies should be concentrated on workplace-exposure controls, accompanied by intense educational and managerial improvements. Methods of secondary prevention appear to be successful but require considerable refinement. Screening (out) of potential new employees is inefficient and likely to remain so; and in any case is beset by difficult ethical and legal issues.There are only a handful of published studies reporting evaluations of preventive programmes. None is entirely rigorous but each suggests that primary and secondary prevention are both feasible and highly effective. The evaluation of preventive strategies is difficult, not only because of the low incidence of the disease in individual workplaces but also because of the failure of many epidemiologists to engage in this work. Considerably more cooperation between scientists in the field, regulatory authorities and industry is required.
Internal quality control: planning and implementation strategies
Authors: Westgard James O 
Published: October 2003

The first essential in setting up internal quality control (IQC) of a test procedure in the clinical laboratory is to select the proper IQC procedure to implement, i.e. choosing the statistical criteria or control rules, and the number of control measurements, according to the quality required for the test and the observed performance of the method. Then the right IQC procedure must be properly implemented. This review focuses on strategies for planning and implementing IQC procedures in order to improve the quality of the IQC. A quantitative planning process is described that can be implemented with graphical tools such as power function or critical-error graphs and charts of operating specifications. Finally, a total QC strategy is formulated to minimize cost and maximize quality. A general strategy for IQC implementation is recommended that employs a three-stage design in which the first stage provides high error detection, the second stage low false rejection and the third stage prescribes the length of the analytical run, making use of an algorithm involving the average of normal patients' data.
The spectrum of carcinoid tumours and carcinoid syndromes
Authors: Lips Cornelis JM , Lentjes Eef GWM , Höppener Jo WM 
Published: October 2003

Carcinoids are neuroendocrine tumours of the gut which may also be found in the bronchus, pancreatic islets and retroperitoneum. They probably arise from gastrointestinal or bronchopulmonary pluripotential stem cells. Carcinoid tumours derived from these cells are potentially malignant; the strength of the tendency for aggressive growth correlates with the site of origin, depth of local penetration and the size of the tumour. Carcinoids occur sporadically or result from specific hereditary tumour syndromes. Mutations and/or aberrant expression of specific genes induce and promote tumour growth. Clinical features include local symptoms due to angulation or obstruction and hepatomegaly due to liver metastases. The carcinoid syndrome commonly involves flushing, diarrhoea, bronchospasm and hypotension. Other distinct syndromes may be caused by tumour release of products that may also be used as biochemical markers in diagnosis and follow-up. Scanning using radiolabelled octreotide, an analogue of somatostatin, sensitively identifies occult primary and metastatic deposits. Localized carcinoid tumours should be resected. Some patients benefit from hepatic resection. Palliation of symptoms is best achieved with octreotide. Hepatic artery chemoembolization may produce long-acting palliation. Further genetic characterization of the different types and stages of carcinoid development as well as assessment of gene expression profiles may improve differential diagnosis, prognosis and treatment.
Tumour markers: their use and misuse by clinicians
Authors: McGinley Peter J , Kilpatrick Eric S 
Published: October 2003

Background: Several guidelines exist on the appropriate use of serum tumour markers in the management of patients with cancer. This study audited tumour marker requesting against these guidelines in a busy teaching hospital over a 12-month period. Methods: All marker requests from 1 April 2001 to 31 March 2002 were collected using the laboratory computer. From one 24-h period, the case notes from all hospital requests [excluding prostate-specific antigen (PSA)] were examined. Results: Tumour marker workload increased by 125% from 1997-98 to 2001-02. Of 27 323 tumour marker requests, 7166 were from general practice, 2312 were requested on hospital admission before further investigation, 612/3636 of CA125 and 98/374 of CA15.3 requests were on men and 12/11585 PSA requests on women. Of 34 case notes examined, 18 had tumour markers measured before biopsy and only nine after. Of 19 patients with 'normal' markers, one had malignancy on biopsy and, of 15 with one or more raised markers, four had normal biopsies. Conclusions: Tumour marker workload is rapidly increasing. Tumour markers are frequently and inappropriately requested, either because they are on patients of the wrong sex, or because they are taken before a cancer diagnosis is reached. Results from these tests can be falsely reassuring or unduly alarming.
Cystatin C improves the detection of mild renal dysfunction in older patients
Authors: O'Riordan Shelagh E , Webb Michelle C , Stowe Helen J , Simpson David E , Kandarpa Madhu , Coakley Anthony J , Newman David J , Saunders Jean A , Lamb Edmund J 
Published: October 2003

Background: Conventional estimates of glomerular dysfunction, including serum creatinine and creatinine clearance, are inadequate in older people. In this study we have compared the diagnostic accuracy of a novel test of kidney disease, cystatin C, against these markers in older patients with a range of renal function. Methods: Fifty-three patients (mean age 79.6 years, range 69-92 years) with a variety of medical diagnoses were recruited via outpatient clinics. Exclusion criteria included active rheumatoid disease, known current malignancy, renal replacement therapy/renal transplantation and cognitive impairment. 51Cr-EDTA was used as the reference method against which the other markers of glomerular filtration rate were compared using regression analyses. Results: The best fit with glomerular filtration rate was given by Cockcroft and Gault calculated clearance ( R2 = 0.83), followed by serum cystatin C ( R2 = 0.79), serum creatinine ( R2 = 0.76) and creatinine clearance ( R2 = 0.73). The accuracy for glomerular filtration rate prediction was poor for all markers. Serum cystatin C detected nearly all patients with mild renal impairment whereas serum creatinine only detected half of these cases. Regression modelling predicted that the upper limit of normal for serum cystatin C would be exceeded as glomerular filtration rate fell below 64 mL/min/1.73 m2, compared with 44 mL/min/1.73 m2 for serum creatinine. Conclusion: Serum cystatin C is a simple and sensitive screening test for kidney dysfunction in older people.
Measurement of renal function in kidney donors using serum cystatin C and β2-microglobulin
Authors: John George T , Fleming Jude Joseph , Talaulikar Girish S , Selvakumar R , Thomas Paaulose P , Jacob Chakko K 
Published: October 2003

Background: The usefulness of serum cystatin C and serum β2-microglobulin (B2M) as markers of glomerular filtration rate (GFR) were compared in kidney donors before and after nephrectomy. Methods: Blood samples were taken from 28 donors (15 women and 13 men) for serum creatinine, urea, cystatin C and B2M estimation a median of 7 days before and 10 days after nephrectomy. Results: Estimated GFR decreased from a median of 86.2 mL/min/1.73 m2 to 60.3 mL/min/1.73 m2, a median decrease of 28.6%. Serum creatinine increased by 40% and urea by 30.4%; serum cystatin C increased by 31.2% and serum B2M increased by 65.6%. Using published data on biological variation, critical values were calculated. An increase in serum creatinine above 18 µmol/L detected the decline in renal function in 26/28 (92.9%) subjects. Increases in serum B2M greater than a critical value of 0.94 mg/L detected 24/28 (85.7%) of these subjects, but the critical value of 0.59 mg/L for cystatin C detected only 8/28 (28.6%). Conclusion: Using critical values, serial measurement of serum creatinine was better than serum B2M in detecting reduced renal function. Because of its large intraindividual variation, serial serum cystatin C estimation was very poor in detecting reduced renal function.
Clinical and technical evaluation of the ACS:OV serum assay and comparison with three other CA125-detecting assays
Authors: Davelaar Elvira M , Schutter Eltjo MJ , von Mensdorff-Pouilly Silvia , van Kamp Gerard J , Verstraeten Rob A , Kenemans Peter 
Published: October 2003

Background: In this study the clinical and technical performance of the CA125- detecting Bayer ACS:OV immunoluminometric serum assay was compared with three other well-established CA125-detecting assays. Methods: A total of 1112 serum samples was included in this evaluation: 462 from apparently healthy women, 153 from patients with benign ovarian disease, 163 from patients with malignant ovarian disease, 10 from patients with borderline ovarian malignancies and 78 samples from 12 ovarian cancer patients during monitoring of disease. Serum samples from women with malignant endometrial ( n = 68) and colon ( n = 32) diseases were also included. Moreover, serum samples from women with benign uterine disease and endometriosis ( n = 136) plus 10 serum samples from men ( n = 7) and women ( n = 3) with human anti-mouse antibodies (HAMA) after immunoscintigraphy were included. All samples were tested in duplicate with the Bayer ACS:OV, the Centocor CA125 II, the Abbott IMx CA125 and the Roche (formerly Boehringer Mannheim) Enzymun-Test® CA125 II assays. Results: The clinical performance of the Bayer ACS:OV assay, assessed in various patient groups, was similar to that of the two other automated assays. In serum from patients with benign diseases the highest values were found in patients with benign ovarian tumours. In the ovarian cancer patients followed during the course of disease we found similar marker patterns with all four assays. In contrast to the Roche Enzymun-CA125 II assay and to a lesser extent the Centocor CA125 II assay, the Bayer ACS:OV assay was less sensitive to interference from HAMA. Conclusion: The Bayer ACS:OV assay is a precise and reliable test for the quantification of CA125 in serum.
Feedback from a point-of-care test for nicotine intake to reduce smoking during pregnancy
Authors: Cope Graham F , Nayyar Pamela , Holder Roger 
Published: October 2003

Background: Smoking is the most important modifiable risk factor for adverse pregnancy outcome in the UK. New tools are needed to improve smoking cessation advice. The aim was to investigate a point-of-care urine test for smoking, to provide feedback to women, to improve awareness about the effects of smoking during pregnancy and to relate the test results to pregnancy outcome. Methods: A cross-sectional randomized controlled trial involving 856 pregnant women. All intervention patients were interviewed at their initial visit and tested for smoking. The test provided visual and numerical feedback. Smokers were followed up and retested at subsequent visits. The control group received anti-smoking counselling as part of routine care, but their smoking was monitored using the test. Both groups were interviewed and retested at 36 weeks' gestation. Results: Self-reported cigarette consumption fell significantly ( P < 0.001) in the intervention group, with 16.2% giving up and 33.3% significantly reducing their cigarette consumption. There was a significant fall in test results from 'booking' to 36 weeks' gestation ( P < 0.0001). In the control group, only 8% reported stopping and 23% reducing their cigarette consumption. Combined smoking test results at 36 weeks correlated significantly with birth weight ( P = 0.006) and body length ( P = 0.011). Conclusions: Point-of-care testing and feedback coupled with counselling can significantly reduce smoking during pregnancy and increase birthweight.
Use of fluorescence polarization immunoassay for salicylate to avoid positive/negative interference by bilirubin in the Trinder salicylate assay
Authors: Dasgupta Amitava , Zaidi Syed , Johnson Myrtle , Chow Loretta , Wells Alice 
Published: October 2003

Background: Significant positive bias of bilirubin in the Trinder salicylate method on automated analysers has been reported. Because the fluorescence polarization immunoassay (FPIA) for salicylate is also widely used in the clinical laboratory, we studied the potential interference of bilirubin in the salicylate FPIA. Methods: Salicylate serum pools (three different pools) were prepared from patients receiving salicylate. We also prepared a normal serum pool containing no salicylate and serum pools containing no salicylate but elevated bilirubin. Aliquots of one salicylate pool were supplemented with various concentrations of bilirubin (42.8- 427.5 µmol/L) and salicylate concentrations were measured by the salicylate FPIA (TDxFLx and AxSYM analysers). We also assayed these specimens with the Trinder salicylate method, using both Synchron LX and Hitachi 917 analysers for comparison with the results obtained by the FPIA method. In another experiment, aliquots of the two other salicylate pools were supplemented with various concentrations of bilirubin (42.8-684.0 µmol/L) in order to further study the effect of very high bilirubin concentrations on the salicylate FPIA. We also added known amounts of salicylate to serum pools containing elevated bilirubin but no salicylate and measured salicylate using the FPIA in order to study the recovery of salicylate in the presence of elevated bilirubin concentrations. Results: The FPIA showed minimal interference from bilirubin. We also observed good recovery of salicylate when specimens high in bilirubin but containing no salicylate were supplemented with known amounts of salicylate and the FPIA was used for the measurement of salicylate concentration. However, we observed falsely low salicylate concentrations with the Trinder method using the Synchron LX (primary wavelength 560 nm, secondary wavelength 700 nm) analyser and falsely increased salicylate concentrations using the same reagent but the Hitachi 917 (primary wavelength 546 nm, no secondary wavelength) analyser in the presence of elevated bilirubin levels compared with the FPIA results. Conclusion: We conclude that the FPIA for salicylate is not affected by high bilirubin concentrations up to 427.5 µmol/L.
Insulinoma: how reliable is the biochemical evidence?
Authors: Chammas NK , Teale JD , Quin JD 
Published: October 2003

Background and methods: We report a case of insulinoma in which the diagnosis was very challenging as some of the biochemical data were consistently equivocal. In order to assess the relative reliability of the analytical tests, retrospective biochemical data on 45 other cases of histologically confirmed insulinoma were evaluated, enabling the most secure diagnostic process to be identified. Results: The data showed that insulin concentrations alone, although measurable, were equivocal in 17% of cases. The addition of C-peptide values clarified the diagnosis in about 50% of the borderline cases, whilst ketone ( β-hydroxybutyrate) concentrations were low during the prevailing hypoglycaemia in all cases. Conclusion: The combination of these three tests is suggested as the most effective method for the biochemical diagnosis of hypoglycaemia due to insulinoma.
Evaluation of the Dade Behring Syva® EMIT 2000 tacrolimus assay on the Bayer Advia 1650
Authors: Stephen DWS , Rooke P , Clark S , Coutts M , Crowe L , Docherty D 
Published: October 2003

Background: The Dade Behring Syva® EMIT (enzyme multiplied immunoassay technique) method for the measurement of tacrolimus in whole blood was evaluated against the Abbott IMx® microparticle enzyme immunoassay (MEIA) method. EMIT measures tacrolimus colorimetrically, whereas MEIA measures the analyte using fluorimetry. Both methods incorporate a protein precipitation step prior to measurement. Method: Whole blood specimens were treated by two types of precipitation technique followed by analysis for tacrolimus by either MEIA or EMIT on the Bayer Advia 1650. Linearity and precision were assessed and correlation analysis performed to evaluate the EMIT assay on the Bayer Advia 1650. Results: The EMIT tacrolimus assay was linear over the concentration range 0.0-22.0 µg/L; the limit of detection was 1.2 µg/L. Correlation between the Syva EMIT and IMx tacrolimus assays was excellent ( r = 0.959) and no significant bias existed between the two methods (mean difference, δ = 0.221 µg/L). Calibration data for the EMIT assay was stable for a period of 24-48 h on the Advia between runs. Conclusion: The Syva EMIT assay for the measurement of tacrolimus in whole blood is suited for daily routine use on the Bayer Advia 1650.