bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Intra-Erythrocytic Low Molecular Weight Lead-Binding Protein in Acute and Chronic Lead Exposure and its Possible Protective Role in Lead Toxicity
Authors: Lolin Yvette , O'Gorman Patrick 
Published: February 2014

A low-molecular-weight protein was measured in erythrocytes from workers with chronic and recent lead exposure, with and without clinical lead toxicity, and from a group of control subjects not exposed to undue environmental lead. The protein was detected in all the workers, but in significantly smaller amounts in those with symptoms, and was absent from controls. The synthesis of the protein is induced at blood lead concentrations above 1·9 μmol/L, but is reduced in workers susceptible to clinical lead toxicity at blood lead concentrations below 4·0 μmol/L. The activity of the red blood cell dithiothreitol (DTT)—activated 5-aminolaevulinate dehydratase (ALA-D) was correlated with the concentration of the low-molecular-weight protein, with both being particularly low in the symptomatic workers. Previous studies have shown that the protein binds lead. By sequestrating excess lead into a non-toxic form, the protein may have a protective role in preventing clinical, and reducing biochemical, lead toxicity.
Serum Angiotensin Converting Enzyme in Sarcoidosis—Its Value in Present Clinical Practice
Authors: Studdy P R , Bird R 
Published: February 2014

Angiotensin converting enzyme (ACE) has a central role in blood pressure homeostasis. It is present in low and fairly constant concentration in the serum and in high concentration in the pulomonary capillary bed. Unusually high serum angiotensin converting enzyme (SACE) activity is present in active sarcoidosis, an observation now confirmed by many investigators. In spite of its lack of specificity as a test for sarcoidoisis, SACE provides a good monitor of disease activity which clinicians find useful in the management of patients with sarcoidosis. There continues to be considerable interest in SACE in sarcoidosis and with the recent development of simpler assays, more centres may be expected to offer SACE measurements as a service. In this paper we discuss the indications for estimating SACE in sarcoidosis and its relevance to current clinical practice.
Interference of Plasma Fluorophores on the Red Blood Cell Zinc Protoporphyrin : Haemoglobin Ratio as Determined on a Haematofluorimeter
Authors: Bartels P C , Helleman P W , Soons J B J 
Published: February 2014

Direct measurement of the zinc protoporphyrin:haemoglobin ratio (ZPP: Hb ratio) in blood samples is performed by using a haematofluorimeter. Interference by non-specific fluorophores can be eliminated by removing the plasma and making the measurement on washed red blood cells (RBCs). After re-suspending RBCs in isotonic saline, haematofluorimeter readings for the ZPP: Hb ratios revealed higher stability in the course of time whereas a good relationship was found with results obtained by application of an extraction method. Separate reference ranges were established for adult male and female subjects. After washing, the mean values calculated for ZPP: Hb ratios of subjects belonging to the reference groups demonstrated a reduction of 0·04 μmol ZPP mol Hb, corresponding with approximately 30%. In the patients' group, application of washing resulted in a variable decrease of ZPP: Hb ratios.
Serum Thyroglobulin—Its Measurement and Clinical Use
Authors: Wilson R , McKillop J H , Jenkins C , Beastall G H , Thomson J A 
Published: February 2014

Radioimmunoassays (RIA) have been shown to be unreliable in measuring serum thyroglobulin levels in patients with antithyroglobulin antibodies. The aim of this study was twofold. Firstly to compare the abilities of two immunoradiometric assays (IRMA), one commercially available, the other an ‘in house’ assay, with a conventional RIA. In addition the prognostic value of serum thyroglobulin levels in patients likely to relapse following a course of antithyroid drugs for Graves' disease was examined. The results obtained showed both of the IRMA methods to be unaffected by the presence of antithyroglobulin antibodies. Serum thyroglobulin levels were found to be poor predictors of relapse or remission following a 12 month course of antithyroid drugs.
Enzyme Immunoassay of Lactoferrin in Newborn Term Infants: Reference Values and Influence of Diet
Authors: Scott P H 
Published: February 2014

Plasma lactoferrin is an acute phase protein which may have a variety of roles in the anti-infective process. As the diagnosis of infection in infants is particularly difficult, measurement of this protein could make a useful contribution, however previous reference values for infants were unsatisfactory. A solid phase enzyme immunoassay for plasma lactoferrin which required only a small specimen of blood was established. It was linear up to 800 μg/L, with a recovery of between 96 and 99%, and had a between batch precision of between 10 and 15%. Using this method we have determined the level of circulating lactoferrin in term infants during the first three weeks of life to be (mean ± SD) 385 ± 113 μg/L which is significantly (P < 0·005) higher than that found in adults (venous plasma 122± 40 μg/ L; capillary plasma 107± 73 Jμg/L). Plasma lactoferrin levels were still significantly higher than those in adults at weeks 7 and 11 (267 ± 176 μg/L and 269±163 μg/L respectively) but not at week 15 (176± 165 μg/L). There were no differences between infants fed breastmilk and those fed on infant formulas. These findings are discussed in terms of the possible origin and role of lactoferrin in the newborn.
Urinary Aluminium Excretion following Renal Transplantation and the Effect of Pulse Steroid Therapy
Authors: Davenport A , Davison A M , Newton K E , Will E J , Gilest G R , Toothill C 
Published: February 2014

Urinary aluminium was measured in 48 patients with primary graft function for 14 days following renal transplantation. The plasma aluminium prior to transplantation was greater in those prescribed aluminium-containing phosphate binders (1·7 ± 0·2 vs 0·6 ± 0·2 μmol/L, P < 0·05) and correlated with the duration of dialysis therapy ( r = 0·42, P < 0·008). After an initial reduction the plasma aluminium returned to pre-transplant values by the fifth day. The 24h urinary aluminium excretion, aluminium clearance and fractional aluminium excretion all increased during the first week to a maximum around the sixth postoperative day, thereafter returning to values obtained during the first postoperative days, suggesting an early ‘wash-out’ of a readily accessible aluminium pool followed by a lower steady state determined by the rate of release of aluminium from tissue stores. For the whole group, aluminium excretion, at this steady state, was five times that of urinary aluminium excretion in normal subjects. Acute allograft rejection was diagnosed in 25 patients, who were treated with pulsed methyl prednisolone. Apart from improving graft function, no additional effect was observed on aluminium excretion, suggesting that the readily accessible aluminium pool does not come from lysosomal release, but probably from aluminium bound to small molecular weight protein.
Syringe Injection Pressure: A Neglected Factor in Blood Po2 Determination
Authors: Gosling P , Dickson G 
Published: February 2014

The mean arterial blood Po2 values of 20 patients' samples taken into Sarstedt 2 mL Monovette™ syringes were found to be initially 0·43 kPa higher and after 15 min storage 0–93 kPa higher than the mean values using Corning 3 mL Blood Gas Kit™ syringes. The Sarstedt syringe allowed entry of small air bubbles and the plunger was noted to be stiff. We speculated that high injection pressures might increase measured Po2 Using each type of syringe, 20 ITU staff injected saline into a Corning 178 pH/blood analyser linked to a pressure transducer via a three-way connector. Mean injection pressures for Sarstedt and Corning syringes were 17·15 and 6·42 kPa, respectively ( P < 0·005). Following injection at pressures between 2·8 and 26·6 kPa, the mean Po2 of equilibrated saline containing an air bubble was 0·80 kPa higher than the mean value obtained at injection pressures of < 2·8 kPa. However, with no air bubble the mean Po2 of equilibrated saline was still 0·45 kPa higher when injected at pressures between 2·8 and 26·6 kPa than the mean value obtained with injection pressures of 2·8 kPa. We suggest that for optimal Po2 determinations syringes should not only allow minimal air contamination but also have plungers that reduce injection pressure to a minimum.
Cerebrospinal Fluid Oligoclonal IgM in Multiple Sclerosis: Analytical Problems and Clinical Limitations
Authors: Giles P D , Wroe S J 
Published: February 2014

A method for detecting cerebrospinal fluid (CSF) oligoclonal IgM is described. Concentrated CSF was separated by agarose isoelectric-focusing and blotted with poly(vinyldifluoride). A double-antibody immunoperoxidase technique with avidin-biotin amplification was used to stain IgM. Special conditions were required to avoid cross-reaction with IgG. The method was applied to 99 patients on whom oligoclonal IgG analysis was performed. Positive IgM results occurred in 17 of the 27 patients positive for oligoclonal IgG, and in two patients negative for oligoclonal IgG, neither of whom had multiple sclerosis (MS). Fifteen of the patients positive for oligoclonal IgM had some IgM bands in their sera. Oligoclonal IgM was not found in the CSF of suspected MS patients without oligoclonal IgG, but occurred in several patients with oligoclonal IgG due to other diseases. ***As a test for MS, oligoclonal IgM was less sensitive than oligoclonal IgG and did not improve specificity.
The Development of Computer Programs to Predict and Minimise the Effect of Sample Pyruvate on Aspartate Aminotransferase Assays
Authors: Davidson D F 
Published: February 2014

Some NADH-linked aspartate aminotransferase (AST) assay systems may produce significant errors due to endogenous pyruvate because the pre-incubation time employed is too short and/or because the reagent lactate dehydrogenase (LD) activity is inadequate. Such errors in patient specimens may go unnoticed if quality control materials themselves contain a low pyruvate concentration. A theory of pyruvate interference in AST assay is formulated and calculation programs are described which will allow a laboratory to assess whether their particular AST methods are likely to be subject to such interference and also to predict a way of removing any error thus identified.
Measurement of Conjugated Diene Lipids by Derivative Spectroscopy in Heptane Extracts of Plasma
Authors: Situnayake R D , Crump B J , Zezulka A V , Davis M , McConkey B , Thurnham D I 
Published: February 2014

A series of experiments are described which show that second derivative spectroscopy can be used to quantify conjugated lipid dienes as markers of lipid peroxidation in heptane extracts of plasma from patients with rheumatoid arthritis, osteoarthritis, and healthy controls. Results obtained by this method gave reasonable agreement with those derived from the measurement of simple absorbance in chloroform/methanol extracts. Two minima were observed in the derivative spectrum of plasma lipid extracts. These minima occurred at 233 and 241 nm and corresponded to absorbance maxima in the conventional UV spectrum. Using a combination of phospholipase hydrolysis, reverse phase high performance liquid chromatography (HPLC) and second derivative spectroscopy we confirmed that these two minima can be attributed to a single fatty acid (9 cis-, 11 trans-linoleic acid) shown previously to account for greater than 90% of diene conjugation in human plasma samples. When the biological isomer 9 cis-, 11 trans-linoleic acid was separated by reverse phase HPLC from the mixture of other plasma phospholipid-2-esterified fatty acids we observed a change in derivative spectroscopy minima from 233 and 241 nm to 228 and 237 nm. Minima at the latter two wavelengths were also seen with pure preparations of the Paint Research Isomer (9 trans-, 11 trans-linoleic acid) which eluted later than biological 9 cis-, 11 trans-linoleic acid using reverse phase HPLC, suggesting that the absorbtion spectra of these pure cis-, trans and trans, trans dienes are similar but can be altered by the presence of other fatty acids in the extract.
Breast Cancer-Associated Hypercalcaemia: A Reassessment of Renal Calcium and Phosphate Handling
Authors: Gallacher Stephen J , Fraser William D , Patel Uday , Logue Fraser C , Soukop Michael , Boyle Iain T , Ralston Stuart H 
Published: February 2014

The mechanisms of hypercalcaemia were assessed in 20 hypercalcaemic patients with breast cancer. Abnormalities suggestive of a PTH-related peptide (PTHrP) mechanism were observed in up to 60% of cases; urinary cyclic adenosine monophosphate (UcAMP) was elevated in nine patients (45%), renal tubular reabsorption of calcium (RTRCa) was elevated in nine (45%) and the renal tubular threshold for phosphate reabsorption (TmPO4) depressed in 12 (60%). While TmPO4 was lower in patients with high UcAMP, there was no consistent relationship between RTRCa and UcAMP or UcAMP and the extent of bone metastases. In a control group of nine normocalcaemic breast cancer patients, bone resorption as assessed by urinary calcium/creatinine ratio was slightly increased but UcAMP, RTRCa and TmPO4 were generally normal. These observations indicate that a PTHrP-mediated mechanism of hypercalcaemia may be operative in up to 60% of patients with breast cancer, irrespective of the presence or extent of bone metastases.
Cytochemical Determination of Intracellular Polymorphonuclear Leukocyte Elastase Content in Patients with Severe Bacterial Infection and Septicaemia Correlated with Coagulation Parameters
Authors: Eldanasouri N , Seitz R , Wolf M , Egbring R , Elden A Shams , Havemann K 
Published: February 2014

Haemorrhagic disorders are known to occur during septicaemia. We studied the role of elastase-like protease (ELP) of human granulocytes in the activation and consumption of clotting factors and their specific inhibitors. Patients with septicaemia and severe bacterial infection were examined for ELP content in polymorphonuclear leukocytes (PNL), as well as plasma levels of ELP complexed to α-1 protease inhibitor, total α-1 protease inhibitor (α-1 PI), clotting factor VII and partial thromboplastin time (PTT). In all patients, a decrease in ELP content of PNL was accompanied by an increase in plasma ELP complexes. The degree to which ELP content of PNL was lowered was related both to the clinical diagnosis and the course of illness. The ELP content of PNL showed a significant positive correlation with plasma factor VII and significant negative correlations with PTT and α-1 PI. These data suggest that ELP release is accompanied by stimulation of the production of α-1 PI, and may contribute in vivo to the consumption of coagulation factors. The correlation with PTT might point to an activation of Hageman factor, which may activate both intrinsic coagulation and ELP release. The estimation of ELP content in PNL in patients with septicaemia is likely to represent intravascular ELP release during the inflammatory process. It appears to be useful in combination with the assay of ELP complex in plasma the level of which is influenced by the capacity of the reticuloendothelial system for clearance.
Feedback of Laboratory Usage and Cost Data to Clinicians: Does it Alter Requesting Behaviour?
Authors: Gama R , Nightingale P G , Broughton P M G , Peters M , Bradby G V H , Berg J , Ratcliffe J G 
Published: February 2014

In a 1 year prospective study we evaluated the effect of feedback of laboratory data on the requesting behaviour of physicians in general medicine. Data on within-hours and out-of-hours clinical chemistry laboratory usage and revenue expenditure for inpatients and outpatients, expressed in terms of clinical workload, were supplied monthly to a group of three consultant physicians in general medicine. With these data the physician could monitor his performance over a period of time and compare it with that of his peers. Two consultants in general medicine who received no information served as controls. Over a period of 6 months, there was a 25%, 13% and 18% decrease in tests ( P < 0·01), requests ( P < 0·05) and revenue expenditure ( P < 0·01) per outpatient visit, respectively, in the intervention group of physicians following the introduction of feedback when compared to their baseline period and to the control group. The decrease ( P < 0·01) was in the commonly requested and ‘seemingly cheap’ tests. There was no significant change in laboratory use and expenditure on inpatients. The feedback of laboratory data was acceptable to the physicians, raised their awareness of laboratory usage and costs and decreased laboratory workload and expenditure.
Increased Urinary Transferrin Excretion in Exercising Normoalbuminuric Insulin-Dependent Diabetic Patients
Authors: O'Donnell M J , Martin P , Cavan D , Parkes A , Chapman J , Chapman C , Barnett A H 
Published: February 2014

The median rate of urinary transferrin excretion is greatly increased by exercise in subjects with uncomplicated type 1 (insulin-dependent) diabetes. This increase is proportionally far greater than that seen in urinary albumin excretion rate after the same exercise. Non-diabetic control subjects showed no rise in urinary transferrin excretion rate following exercise. N-acetyl-β-D-glucosaminidase excretion rate was higher in diabetic than control groups but did not rise with exercise. Our results suggest that patients with apparently uncomplicated diabetes have abnormal renal function. In this group an elevated urinary transferrin excretion rate appears to be a more sensitive indicator of altered renal function than is elevated albumin excretion rate. The mechanism underlying exercise-induced urinary loss of transferrin remains to be elucidated.
Properties of Serum Alcohol Dehydrogenase in Nigerians with Primary Hepatoma
Authors: Ogunleye I O , Olusi S O 
Published: February 2014

The serum activity of alcohol dehydrogenase was determined in healthy controls and in patients with liver diseases. The mean activity in hepatoma (6·4 ± 1·0U/L) was significantly higher (P<0·05) than the mean values in liver cirrhosis (2·7 ± 0·5U/L); hepatitis (4·3 ± 1·OU/L), obstructive jaundice (2·9 ± 0·5U/L) and healthy controls (0·7 ± 0·1U/L). Alcohol dehydrogenase purified by CM-cellulose chromatography from the sera of patients with hepatoma had a higher affinity for butanol long chain saturated and unsaturated alcohols than the purified enzyme from healthy controls. Similarly, hepatoma alcohol dehydrogenase oxidized ethanol very poorly ( KM = 154μM) when compared with that from healthy controls ( KM = 40·2μM). Hepatoma alcohol dehydrogenase was inhibited by pyrazole while those of other liver diseases and the healthy controls were not. These properties of serum alcohol dehydrogenase may prove useful in the early diagnosis of hepatoma since biochemical changes occur before morphological changes in the development of cancer.
Circulating Levels of Tartrate-Resistant Acid Phosphatase in Macrophage-Activated Lung Disease
Authors: Kehely Anne , Moss Donald W 
Published: February 2014

Tartrate-resistant acid phosphatase (TrACP) is abundant in alveolar macrophages, suggesting that these cells might contribute to the activity of this isoenzyme in sera of patients with conditions characterized by activation of alveolar macrophages. TrACP was therefore measured in patients with pulmonary sarcoidosis and cryptogenic fibrosing alveolitis and compared with values in controls. Since osteoclasts are known to be the main source of TrACP in serum several indices of bone-turnover were also measured: Serum bone-specific alkaline phosphatase and urine hydroxyproline: Creatinine ratios. Patients with Paget's disease of bone constituted a reference group presenting increased bone turnover. TrACP was not significantly higher in the lung-disease groups than in controls, although there was a strong positive correlation with angiotensin-converting enzyme in pulmonary sarcoidosis. As expected, TrACP activity was elevated together with the other indices of bone turnover in Paget's disease. It is unlikely that TrACP from alveolar macrophages contributes significantly to serum acid phosphatase activity in lung disease.
Role of Reactive Oxygen Species in the Generation of Fluorescence by Glycation
Authors: Le Guen C A , Jones A F , Barnett A H , Lunec J 
Published: February 2014

Fluorescence (excitation 360 nm, emission 454 nm) generation in glycated albumin was investigated. Antioxidants and the metal chelator desferrioxamine (DFX) were used to study the mechanism of fluorescence generation. Delipidation studies, reverse phase chromatography and scanning fluorimetry were performed to examine the nature of this fluorescence. The mechanism of action of aminoguanidine, a compound which has been shown to inhibit the formation of visible fluorescence in proteins in vitro and in vivo was investigated in relation to glycation and by comparison with compounds with structural similarities. We conclude that hydrogen peroxide, metal ions and hydroxyl radicals are involved in fluorescence generation in glycated albumin, which is largely lipid in nature, and arises through glycation, amino acid oxidation and changes in bound lipid. Our results suggest that the action of aminoguanidine is not specifically related to blocking of ketoamine groups on glycated proteins as previously suggested.
Laboratory Diagnosis of Phaeochromocytoma: Which Analytes Should We Measure?
Authors: Graham P E , Smythe G A , Edwards G A , Lazarus L 
Published: February 2014

There is a diversity of advice in the literature as to which biochemical assays are best suited to the investigation of patients with a suspected phaeochromocytoma. The challenge for the clinical laboratory is to select those assays which detect all phaeochromocytomas, whilst having the lowest incidence of false positive diagnoses. We compared the sensitivity and specificity of a wide range of assays currently used for the biochemical diagnosis of phaeochromocytoma using either specific gas chromatographic-mass spectrometric (GC/MS) or high performance liquid chromatography-electrochemical detection (HPLC/ED) techniques. Noradrenaline (NA), adrenaline (ADR), dopamine (DA), 3,4-dihydroxyphenylglycol (DHPG), hydroxymethoxymandelic acid (HMMA), normetanephrine (NMET) and metanephrine (MET) were measured in 24 h urine specimens from 20 patients with histologically proven phaeochromocytoma and a large group of patients referred for investigation but subsequently found not to have a phaeochromocytoma. Because phaeochromocytomas are a heterogeneous group of hormone secreting tumours, no single analyte could achieve 100% sensitivity; 100% sensitivity was achieved only when the combination of both NA and ADR or NMET and MET was used. DA, DHPG and HMMA all had poor sensitivities. HMMA had a sensitivity of 70% when using the upper 95% confidence level (48μmol/24 h) of the non-tumour patients as the cut-off. By lowering the cut-off to 35μmol/24 h the sensitivity could be increased to 100% but at the expense of the specificity which was decreased from 98 to 92%. On the basis of this study we recommend the specific measurement of either NA and ADR or NMET and MET as the most suitable analytes for the detection of phaeochromocytoma, and further that, due to its poor specificity, HMMA be abandoned as a suitable analyte.