bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biochemical Markers in Ovarian Cancer: Possibilities and Limitations
Authors: Haije W G 
Published: February 2014

Cancer of the ovary is the commonest cause of death from gynaecological neoplasms. As ovarian tumours are relatively inaccessible, there is a great need for methods to improve early diagnosis and to assist with the management of patients with this disease. In this presentation the state of the art is discussed with regard to the usefulness of the presently recognised ‘tumour antigens’ and other biochemical markers in ovarian cancer. Of the oncodevelopmental antigens, only alpha fetoprotein and chorionic gonadotropin are well established as good markers in tumours with, respectively, yolk sac and trophoblastic elements. Carcinoembryonic antigen seems from our own experience to be an unreliable marker in cancer of the ovary. In epithelial tumours, which constitute the majority of ovarian malignancies, mostly serous and mucinous cystadenocarcinomas, some tumour products have been described, which may have potential as a marker, for example, ovarian cancer associated antigens, some glycoprotein glycosyltransferases, and also carcinoplacental alkaline phosphatases (CPAP). Recently, in patients with epithelial ovarian tumours attending our institute, multiple biochemical markers have been studied, including CPAP, phosphohexose isomerase, and some acute phase reactant proteins. The preliminary results, which will be discussed, show that longitudinal studies of some of these markers could have clinical application in follow-up. It must be concluded that, in spite of all efforts so far, and although some markers may become useful, early detection of ovarian cancer is a goal still to be reached by clinical chemistry in the field of oncology.
Comparison of Routine Analytical Methods in the Netherlands for Seven Serum Constituents Using Pattern Recognition
Authors: Jansen Rob T P 
Published: February 2014

Routine analytical methods for seven serum analytes (calcium, chloride, cholesterol, glucose, inorganic phosphate, urate, and urea) are assessed using data from the Netherlands coupled external/internal quality control program. From the results of a trial each method can be described by four features: measures of bias, between-day precision, tendency to give erroneous results, interlaboratory variance. These four features of each trial determine a vectorpoint in the four-dimensional space for a particular method. From 12 trials a maximum of 12 vectorpoints per analytical method was obtained. Pattern recognition techniques allowed the detection of clusters of vectorpoints. Analytical methods having vectorpoints classified in different clusters perform differently. The mean feature values of the vectorpoints forming a cluster determine the quality of that cluster. A weighting procedure reveals the importance of the respective features for discriminating the clusters. For all of the seven analytes, clusters of vectorpoints were found. Different features appeared to contain discriminatory power for different analytes. For six analytes (calcium, chloride, cholesterol, glucose, inorganic phosphate, and urea) an analytical method was found to classify predominantly in the qualitative best cluster. One analytical method for the determination of chloride and one for glucose, inorganic phosphate, and urea did not cluster at all.
On the Reliability of the Henderson-Hasselbalch Equation in Routine Clinical Acid-Base Chemistry
Authors: Maas A H J , Rispens P , Siggaard-Andersen O , Zijlstra W G 
Published: February 2014

This paper deals with the variability of the practical coefficient of the first ionisation equilibrium of carbonic acid as related to the CO2 in the liquid phase (Henderson-Hasselbalch equation) [Formula: see text] and that of the practical coefficient of the first ionisation equilibrium of carbonic acid as related to the CO2 in the gas phase (modified Henderson-Hasselbalch equation) [Formula: see text]
Colorimetric Assay for N-Acetyl-β-D-glucosaminidase (NAG) in Pathological Urine Using the ω-Nitrostyryl Substrate: The Development of a Kit and the Comparison of Manual Procedure with the Automated Fluorimetric Method
Authors: Yuen C T , Kind Patricia R N , Price R G , Praill P F G , Richardson A C 
Published: February 2014

This paper describes a comparison of the recently developed substrate 2-methoxy-4-(2′-nitrovinyl)-phenyl-2-acetamido-2-deoxy-β-d-glucopyranoside (MNP-GlcNAc) and the corresponding 4-methylumbelliferyl substrate (4-MU-GlcNAc) for the determination of urinary NAG. A good correlation ( r = 0·977) was found between NAG activities in 366 urine samples from renal transplant patients determined by either the fluorimetric method or the colorimetric procedure. The colorimetric method may be used with confidence as an alternative to the fluorimetric assay and does have the advantage that colorimetry is widely used in clinical chemistry laboratories. Sample blanks are not normally required unless there is blood contamination in the urine which can easily be identified visually. The incorporation of the MNP-GlcNAc substrate into a kit suitable for the assay of urinary NAG using a simple battery-operated miniphotometer is also described. The presence of elevated NAG levels in urine can be detected rapidly and this procedure is suitable for routine monitoring of renal patients in the laboratory and may prove to be suitable for use by non-laboratory personnel in clinics or on the ward.
The Microheterogeneity of Human Liver and Serum Ferritins Measured on Minute Amounts of Ferritin in Crude Samples
Authors: Zuyderhoudt F M J , Linthorst C 
Published: February 2014

A method is presented to measure the microheterogeneity of ferritin in μg amounts, without purifying the samples extensively. Ferritin-containing samples such as serum and homogenized liver-biopsy specimens were mixed with Sephadex G-75 and ampholines. Isoelectric focussing was performed and the pH gradient in the Sephadex was measured. The Sephadex was divided into predetermined pH ranges and the ferritin eluted from these fractions. Ferritin concentration was measured by an enzyme-linked immunosorbent assay. The method proved to be reproducible. The isoferritin profiles of different human serum and liver tissue samples were quite variable. In most cases serum ferritins focussed between approximately pH 5·5 and pH 4·9 and liver ferritins between approximately pH 5·8 and pH 5·3. We examined whether there was a similarity in the isoferritin patterns of serum and liver of distinct patients. We also studied liver tissue and serum from a patient with haemochromatosis and from a child with iron overload of unknown origin. In the serum of our patients the isoferritin pattern had shifted to lower pI when compared with that found in liver tissue. Only in the case of a patient with transfusion iron overload were basic isoferritins measured in the serum. In this case no liver biopsy specimen was available for comparison.
Affinity Chromatography: A Precise Method for Glycosylated Albumin Estimation
Authors: John W G , Jones A E 
Published: February 2014

A method is described for the estimation, in plasma, of glycosylated albumin, using the commercially available affinity chromatographic material Glycogel B (immobilised m-aminophenylboronic acid on an agarose support) to separate the glycosylated and non-glycosylated albumin, followed by the analysis of albumin concentration using rocket Immunoelectrophoresis. Glycosylated albumin and glycosylated haemoglobin showed good correlation (r=0·91) when both are estimated by affinity chromatography. The glycosylated albumin method displays good within-batch (2·8–4·4% CV) and between-batch (2·9–5·4% CV) precision, and the method is not affected by haemolysis. Using this method a reference range of 2·0–5·4% was found for glycosylated albumin. Levels of glycosylated albumin in diabetics (10·06±3·23%) were found to be significantly higher ( P<0·001) than those in non-diabetics (3·72±0·85%). It was found that loading more than 3 mg of albumin on to a 1 mL affinity column must be avoided, as this appears to overload the column.
Performance of a Quality-Assessment Scheme for Blood Glucose Meters in General Practice
Authors: Burrin J M , Williams D R R , Price C P 
Published: February 2014

We describe our experience with a quality-assessment scheme for Glucometer users in General Practice based on simultaneous blood samples taken on filter paper strips and posted to the laboratory. The accuracy of results from these blood glucose meters outside the laboratory was below generally accepted laboratory standards; 30% of results fell outside ± 20% of the laboratory value. Only 58% of the filter paper strips sent out were returned for analysis, suggesting a lack of awareness of the benefits and importance of such a scheme by the G.P. Glucometer users.
Comparison of the Analytical Characteristics and Clinical Usefulness in Tumour Monitoring of Fifteen hCG(-β) Immunoassay Kits
Authors: Thomas C M G , Segers M F G , Whoux P C 
Published: February 2014

Fifteen immunoassay kits for serum hCG(-β) measurements have been compared for their analytical characteristics and clinical usefulness in tumour monitoring. Three out of 13 radioimmunoassays and two sandwich hCG immunoassays represent the ‘one-component’ techniques for intact hCG detection since they are based on antiserum raised against intact hCG. Within this group, method-comparison slopes ranged between 0·149 and 0·374. The remaining 10 radioimmunoassays all apply antiserum against hCG-β and are designated ‘two (or more)–component’ assays since they detect both intact hCG and the free β-subunit (‘total hCG’). For this reason these assays are of potential value for tumour monitoring. Additional criteria for this are: (1) the expression of assay results in terms of 1st IRP-hCG instead of the unstructured use of the 2nd IS or the 1st IRP-hCG-β; (2) documentation of cross-reactivities especially for the free β-subunits of hCG and hLH which are almost completely lacking; (3) establishment of the minimum detectable dose in the presence of normo-to-hypergonadotrophic hLH levels in serum (the ‘clinical sensitivity’) to allow the follow-up of tumour regression especially in the low-dose region. Method-comparison analysis for these assays revealed regression slopes between 0·001 and 0·873.
The Effects of Septic Complications upon the Serum Protein Changes Associated with Thermal Injury
Authors: Moody B J , Shakespeare P G , Batstone G F 
Published: February 2014

The levels of 12 serum proteins including ‘acute-phase reactants’, immunoglobulins and albumin were measured in 20 patients suffering from thermal burns. The acute-phase reactants: C-reactive protein, α-1 antitrypsin, α-1 antichymotrypsin, haptoglobin and orosomucoid, all increased in concentration. Highest levels, which showed significant correlations with injury severity, occurred at 6–8 days post-burn. The levels of albumin, α-1 lipoprotein and transferrin were decreased. The immunoglobulins IgG, IgA and IgM showed an initial decrease followed by a steady return to normal levels. Four patients, of whom three died, developed serious sepsis. The levels of α-1 antichymotrypsin and C-reactive protein were much higher in patients with sepsis than in those without sepsis. The highest levels occurred during and often before the episode of sepsis was clinically evident. The immunoglobulins especially IgG and IgA were lower in those patients who developed sepsis than in those who did not. The results suggest that the serum levels of either C-reactive protein or α-1 antichymotrypsin could be used both as an aid to diagnosis of sepsis and also to monitor the effect of therapy.
The Influence of Age and Sex on Tests of Thyroid Function
Authors: Franklyn J A , Ramsden D B , Sheppard M C 
Published: February 2014

Serum concentrations of total thyroid hormones, thyroid hormone binding proteins, free thyroid hormones and thyroid stimulating hormone (TSH) were measured in a large group of healthy normal subjects ( n = 218) to determine the influence of age and sex on tests of thyroid function. No effect of age on measurements of total thyroxine (T4), total triiodothyronine (T3) or reverse T3 was evident. Concentrations of free T4, free T3 and TSH were similarly unaffected, suggesting that increasing age alone does not significantly influence thyroid hormone measurements. There was, however, a rise in thyroxine-binding globulin (TBG) concentration with increasing age and a fall in thyroxine-binding prealbumin (TBPA). An influence of sex on tests of thyroid function was clearly evident. Levels of total T4, total T3, free T4 and the T4: TBG ratio were lower in women between 16 and 49 years than in men, despite an increase in TBG. Lower levels of free T3 were confined to the group of women aged 16–29 years. TSH values were unaffected by sex. These results suggest that sex hormone status in the pre-menopausal female subject may result in an increase in TBG concentration, and in addition may have an opposing effect on circulating thyroid hormone concentrations.
Clinical Value of a Sensitive Immunoradiometric Assay for TSH
Authors: Allen K R , Scott R D M , Hewitt J V , Watson D 
Published: February 2014

We have investigated a sensitive immunoradiometric assay for serum thyroid-stimulating hormone (TSH) in 45 thyrotoxic patients not on treatment, 464 euthyroid patients and 111 hypothyroid patients on replacement therapy. Forty-three thyrotoxic and seven euthyroid patients were found to have an undetectable TSH (less than 0·2 mlU/L). Previous work has shown a very clear separation of thyrotoxic and euthyroid patients using sensitive TSH assays. However, our extended study here has revealed that a significant number of euthyroid patients with undetectable TSH (1·5% in our study) are likely to be found if TSH becomes the initial test for thyroid function. Thirty of the hypothyroid patients on thyroxine were found to have undetectable TSH, but only one showed clinical signs of thyrotoxicosis. Most of the patients, although having raised serum free T4, had serum free T3 levels within the euthyroid range or just slightly elevated.
Intra-Individual Variation: Significant Changes in Parameters of Lipid and Carbohydrate Metabolism in the Individual and Intra-Individual Variation in Different Test Populations
Authors: Godsland IF 
Published: February 2014

Fasting serum triglyceride, cholesterol, HDL cholesterol, HDL2&3 cholesterol, fasting plasma glucose and insulin and haemoglobin A1 were measured under standardised conditions in a group of laboratory volunteers. Intra-individual variation was calculated for each parameter from weekly measurements on at least eleven successive occassions, and the minimum change in each parameter that would be significant at the level P < 0·05 was calculated. A further study compared intra-individual variation in different test populations. Data from the group of laboratory volunteers were taken to represent intra-individual variation under standard test conditions with an informed test population and data from a group of regularly monitored out-patients undergoing drug therapy for hypercholesterolaemia were taken to represent intra-individual variation under standard conditions in a typical test population. A group of inpatients under strict dietary control provided information on variation under extreme standardisation of test conditions. Intra-individual variation was greatest for all parameters in the outpatient population. Extreme standardisation of test condition reduced intra-individual variation beyond that of the laboratory volunteers only in the case of serum triglyceride.
Factors That Affect the Induction of Gamma Glutamyltransferase in Epileptic Patients Receiving Anti-Convulsant Drugs
Authors: Braide Solomon A , Davies T J 
Published: February 2014

Serum samples from 335 epileptic patients receiving one or more anticonvulsant drugs, phenobarbitone, primidone and phenytoin, have been analysed for biochemical liver profile (BLP) and serum drug concentration. The results show that the induction of serum gamma glutamyltransferase (GGT) is affected by the sex and age of the patient, type of anti-convulsant drug prescribed and duration of treatment. It is less affected by serum drug concentration. It is suggested that these factors must be considered when interpreting results involving serum GGT activity as the index of microsomal enzyme induction.
Evaluation and Clinical Application of a Two-Site Immunoradiometric Assay for Alpha-1-Foetoprotein Using Readily Available Reagents
Authors: Stevenson J D , Chapman R S , Perry B , Logue F C 
Published: February 2014

The development and evaluation in routine clinical practice of a simple, rapid, high-throughput, immunoradiometric assay (IRMA) for alpha-foetoprotein (AFP) in serum and amniotic fluid is described. The assay uses readily available reagents; a radioiodinated mouse monoclonal antibody produced by the authors and the immunoglobulin G (IgG) fraction of a polyclonal sheep anti-human-AFP serum covalently linked to Sepharose CL-4B. Both antibodies are distributed by the Scottish Antibody Production Unit (Law Hospital, Carluke). The results of an extensive comparative trial between the IRMA and a radioimmunoassay (RIA) are presented. A high-dose ‘hook’ effect is not a problem in this system. Quantitative recovery was obtained, independent of the assay diluent. The IRMA has high sensitivity and a wide working range. Improved assay precision allowed a clinically significant change in the intervention limits.
When is Serum Albumin Worth Measuring?
Authors: Whicher J , Spence C 
Published: February 2014

This paper critically examines the usefulness of serum albumin measurement in the light of current laboratory practice and knowledge of the pathophysiology of albumin metabolism. The main conclusions and recommendations are as follows: Albumin measurement forms a limited, but useful part of the investigation of liver disease; a normal serum albumin concentration makes the diagnosis of cirrhosis unlikely, while a low level in viral hepatitis suggests either severe hepatocellular damage or other complications. Albumin measurement is essential in selecting patients for, and in determining the amount and frequency of, albumin replacement. Serum albumin concentration provides a useful indication of prognosis in myeloma. In the long-term management of patients undergoing enteral or parenteral nutrition, serum albumin concentration is one of several parameters which, together, are useful in predicting the outcome of treatment. (v) The serum albumin concentration may provide a clue to the aetiology of unexplained oedema. Serum albumin measurement is useful in indicating the level of ionised calcium and of unbound unconjugated bilirubin.
An External Quality Assessment Scheme for Total Bilirubin
Authors: Johnson Keith R 
Published: February 2014

A regional quality assessment scheme for total bilirubin methods is described. The scheme provides liquid sera at three concentrations and allows method linearity to be assessed. The sera were shown to be adequately stable over the periods of assessment. An integral part of the scheme is quick feedback of comparative performance between and within participant laboratories. Data presentation has some novel aspects to it (a) the weekly report shows deviation from the weighed-in value and intra- and inter-laboratory variation (b) the 6-monthly summary gives the average performance of the best three laboratories as achievable precision. There is also dialogue with participants on all aspects of the scheme including the material provided.
Serum Aluminium Measurement by DC Plasma Emission Spectrometry
Authors: Roberts N B , Williams P 
Published: February 2014

A serum aluminium assay has been established using a DC plasma emission spectrometer and calibration with serum based standards. The assay is linear between 0·20 and 18·0 μmol/L aluminium. The procedure gives good analytical recovery and precision. The assay was validated by comparison(s) with an electrothermal atomic absorption (ETAAS) procedure which showed good agreement. Serum aluminium concentrations have been compared in normal individuals, in undialysed chronic renal failure patients with or without aluminium hydroxide treatment, and in dialysed patients treated with oral aluminium hydroxide. Non-dialysed patients had higher serum aluminium concentrations if treated with aluminium hydroxide. Haemodialysis patients had the highest serum aluminium concentrations whilst those on peritoneal dialysis had levels similar to those of the non-dialysed chronic renal failure group.
Essential Considerations in the Provision of Near-Patient Testing Facilities
Authors: Marks Vincent 
Published: February 2014

(1) Near-patient testing (NPT) is both practicable and in some situations desirable. (2) Like all new technologies its apparent simplicity often belies its complexity and masks the need for attention to detail in order to achieve optimum effects and avoid disasters. (3) Though technically unskilled individuals are capable of using it, they must undergo training in the elements of safety, sample collection, quality control, quantitation and documentation before being authorised to provide analytical services for patients. (4) Health Authorities should be encouraged to adopt a policy of integration of NPT and clinical laboratory services in order to reduce unplanned use and abuse of NPT facilities which is not only wasteful and divisive, but also dangerous. This has recently been emphasised in the United Kingdom by the release of a Hazard Notice (HN (Hazard) (87) 13) by the Department of Health and Social Security. The experienced clinical biochemist will, by virtue of training and experience, usually be the most suitable person in a Health District to advise on many of the issues involved in NPT. It should therefore, be the responsibility of laboratory staff to work with management, clinical, and nursing staff to: choose appropriate sites for the various levels of service to be provided to meet a clinical need; select the equipment and reagents to be employed; provide training in the use of the apparatus, quality control and safety; authorise accredited users and oversee the quality assurance programme. (5) Laboratory staff will need to involve themselves closely in the financial implications of NPT both for the laboratory's benefit and that of clinical practice within the hospital and/or community as a whole.
Serum Fructosamine Does Reflect Levels of Glycated Serum Albumin in Insulin-Dependent Diabetics
Authors: Lloyd D R , Marples J 
Published: February 2014

Fructosamine was measured in the serum of 62 patients with insulin-dependent diabetes (IDD) and 32 non-diabetics and the results compared with glycated albumin levels (GSA) measured using the affinity medium Cibarcron blue F3GA. Good correlations were found both for the IDD patients ( r=0·93) and the combined group of IDD plus non-diabetics ( r=0·95). We conclude, that fructosamine measurements accurately reflect GSA concentrations, and, therefore, provide a practical method for assessing intermediate term glycaemia in IDD.