bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differences in Serum Luteinizing Hormone Measurements by Immunoradiometric Assay Induced by Kinetic Manipulation of Assay Conditions are Dependent on the Endocrine Milieu of Serum
Authors: Olukoga A O , Mitchell R , Walton L , Robertson W R , Laing I 
Published: February 2014

Divergent estimates for luteinizing hormone (LH) in individual serum samples may be given by different immunoassays. In order to investigate this phenomenom further, we have studied the effect of differences in assay kinetics within the same immunoradiometric assay (IRMA) configuration on LH measurement in sera from different endocrine states. Three pairs of monoclonal/polyclonal two-site IRMA systems for LH were developed from three LH monoclonal antibodies and a common polyclonal anti-human chorionic gonadotrophin. For IRMA systems a short and long assay, which were different only with respect to the incubation time (1/2 h and overnight respectively), of the labelled monoclonal first antibody were performed. The IRMAs were all standardized against the LH international reference preparation 68/40. LH concentrations were measured by all the IRMAs in sera obtained from normal men ( n = 11) and from women with polycystic ovarian syndrome (PCO; n = 13). In normal men, there were no differences in LH estimates between the short and the long assays of the three IRMA systems, and the ratios of long to short assays were similar for all the systems. However, in PCO there were significant differences between short and long assays and the ratios of long to short assays were different for the IRMA systems. These results indicate that kinetic differences between IRMAs of the same antibody configuration can be associated with differences in measured LH concentrations, depending on the endocrine status of the sera studied. As LH glycoform patterns are known to differ between normal men and PCO, the observed changes in LH estimates may be due to the different glycoform composition.
The Entero-Insular Axis in Polycystic Ovarian Syndrome
Authors: Garaa R , Norris F , Wright J , Morgan L , Hampton S , Watkins K , Marks V 
Published: February 2014

We investigated the contributions made by the entero-insular axis, proinsulin and the fractional hepatic extraction of insulin to the hyperinsulinaemia characteristic of polycystic ovarian syndrome (PCOS). We measured plasma glucose, gastric inhibitory polypeptide (GIP), glucagon-like peptide-1 (7–36 amide) (GLP-17–36 amide), immunoreactive insulin (IRI), intact proinsulin (IPI), and C-peptide concentrations during a 75 g oral glucose tolerance test in seven normal weight women with PCOS and eight healthy women. Women with PCOS had higher fasting ( P = 0·05) and integrated ( P < 0·01) IRI concentrations than controls. Fasting C-peptide levels were similar in both groups but integrated C-peptide ( P < 0·05) concentrations were greater in PCOS subjects than controls. Fasting and integrated concentrations of glucose, GIP and GLP-17–36 amide were similar in subjects with PCOS and controls. Although fasting IPI concentrations were similar in both groups, integrated IPI concentrations were higher ( P = 0·05) in patients with PCOS. Women with PCOS had similar fasting but higher ( P <0·05) integrated IRI: C-peptide molar ratios than controls. Fasting and integrated IPI: IRI molar ratios were similar in both groups. These results confirm that lean women with PCOS have peripheral hyperinsulinaemia. The mild fasting hyperinsulinaemia is due to increased pancreatic secretion, whereas the stimulated hyperinsulinaemia is due to both pancreatic hypersecretion and reduced fractional hepatic extraction of insulin. Hyperproinsulinaemia is modest and appropriate in PCOS. GIP and GLP-17–36 amide do not contribute to the stimulated hyperinsulinaemia in PCOS.
Serum Osteocalcin, Total and Bone-Specific Alkaline Phosphatase following Isolated Tibial Shaft Fracture
Authors: Bowles Shirley A , Kurdy Nazeer , Davis Alison M , France Michael W , Marsh David R 
Published: February 2014

We report the changes in osteocalcin concentrations and in total and bone specific alkaline phosphatase activity occurring in the twenty week period following tibial shaft fracture in 20 subjects. Bone formation during the healing process is reflected by progressive increases in the concentration of osteocalcin and bone specific alkaline phosphatase after week 5 and the latter correlated with the height and weight of the subject. In the early post injury period, total alkaline phosphatase activity increased whereas that of the bone isoenzyme initially fell, starting to rise again during the second week. After an immediate post injury rise, osteocalcin concentration also decreased, reaching a nadir by week 5. As only three of our subjects demonstrated delayed union, we have not been able to demonstrate that biochemical monitoring of the healing process can provide an indication of prognosis in tibial shaft fracture.
Steroid Sulphatase Deficiency: Identification of Heterozygotes Using Hydrolysis of Dehydroepiandrosterone Sulphate by Peripheral Leucocytes
Authors: Lowis E I , Oakey R E 
Published: February 2014

Diagnosis of X-linked recessive ichthyosis, which is expressed only in males, can readily be made by measurement of leucocyte steroid sulphatase activity. However, because the gene for steroid sulphatase activity partly escapes from the process of X-chromosome inactivation associated with gene dosage compensation, identification of heterozygotes (females) is more difficult. We have measured the steroid sulphatase (by hydrolysis of dehydroepiandrosterone sulphate) and β-glucuronidase (by hydrolysis of methylumbelliferyl glucuronide) activities in leucocytes from 18 heterozygotes, 100 normal females, 100 normal males and 11 affected subjects. When the ratio of the activities of steroid sulphatase and β-glucuronidase in mixed leucocytes was plotted as a function of the steroid sulphatase activity, 85% heterozygotes were distinguished from normal females. Measurement of steroid sulphatase activity alone with these cells enabled identification of 78% heterozygotes. Measurements on mononuclear leucocytes were much less effective. Thrombocytes showed 1% of the steroid sulphatase activity of leucocytes. In females, leucocyte steroid sulphatase activity was independent of the stage of the ovarian cycle at which the cells were collected.
The Effect of Eccentric Exercise on Serum Creatine Kinase Activity in Different Ethnic Groups
Authors: Sherwood R A , Lambert A , Newham D J , Wassif W S , Peters T J 
Published: February 2014

Eccentric exercise causes release of muscle creatine kinase (CK) 3–4 days after exercise. Racial variation in basal serum CK has been reported but the reasons for this are unknown. We studied 30 subjects of different ethnic origin (Caucasian, Afro-Caribbean, Asian) before and after eccentric exercise. Basal serum CK was significantly higher in the Afro-Caribbean group (201 ± 134IU/L, median ± SD) compared to Caucasians (81 ± 57 IU/L). The Asian group had intermediate CK values (144 ± 93 IU/L). The intra-individual range of peak post-exercise CK values obtained was very wide (95–30 200 IU/L) with little difference in median CK between the Afro-Caribbean (8450 ± 9020 IU/L) and Caucasian groups (7600 ± 8800 IU/L). The median value for the Asian group was lower (594 ± 5410 IU/L). A sub-group of 15 individuals undertook a second bout of exercise 2 weeks later and all subjects demonstrated a training effect resulting in a marked attenuation of enzyme efflux. The variation in CK between the ethnic groups was not related to measurements of muscle strength or body mass, although the torque: body mass ratio followed the same order as the basal CK, i.e. the Afro-Caribbeans had the highest values. These results highlight the importance of considering ethnic origin and previous exercise history when interpreting serum CK assay results.
Benzodiazepine Misuse by Drug Addicts
Authors: Garretty Deborah J , Wolff Kim , Hay Alastair W M , Raistrick Duncan 
Published: February 2014

Using a high-performance liquid chromatography method, we measured seven commonly prescribed benzodiazepines (chlordiazepoxide, nitrazepam, nordiazepam, oxazepam, lorazepam, temazepam and diazepam) in 100 urine samples obtained from patients attending the Leeds Addiction Unit. All of the urines selected for investigation were positive for benzodiazepines using an EMIT (Enzyme Immunoassay) screen. Forty-four of the urines contained a range of benzodiazepines, none of which had been prescribed. Nitrazepam was detected most frequently (61 urine samples), but had not been prescribed to any of the patients in this study. Chlordiazepoxide was detected in 49 urine samples, although it had been prescribed to only five patients. Temazepam was detected in 28 urine samples. Fourteen patients providing 21 urine samples had been prescribed temazepam for treatment. However, temazepam was detected in only 14 of these samples. Multiple benzodiazepine abuse was evident from the high rate of detection of unrelated benzodiazepines.
Ovarian Steroids Regulate the Expression of Basic Fibroblast Growth Factor and its mRNA in Fibroblasts Derived from Uterine Endometrium
Authors: Fujimoto Jiro , Hori Masashi , Ichigo Satoshi , Tamaya Teruhiko 
Published: February 2014

The role of stromal cells in basic fibroblast growth factor (FGF) supply for endometrial neovascularization during the menstrual cycle was investigated. The concentrations of intracellular and secreted FGF, and FGF mRNA expression were determined in fibroblasts derived from uterine endometrium as a substitute for stromal cells. The influence of sex steroids on protein and mRNA expression was investigated. The concentration of FGF and its mRNA expression in the fibroblasts was significantly increased by oestradiol, and these increased concentrations were diminished by progesterone. It is suggested that oestrogen stimulates FGF secretion from the stromal cells, an effect which is inhibited by progesterone. Therefore, endometrial neovascularization might be partially regulated by stromal-derived FGF under the influence of sex steroids, through a paracrine cell-to-cell interaction.
Kinetic Analysis and Tissue Distribution of Human D-Glycerate Dehydrogenase/Glyoxylate Reductase and its Relevance to the Diagnosis of Primary Hyperoxaluria Type 2
Authors: Giafi C F , Rumsby G 
Published: February 2014

The enzyme D-glycerate dehydrogenase (D-GDH; EC 1.1.1.29), which is also believed to have glyoxylate reductase (GR; EC 1.1.1.26/79) activity, plays a role in serine catabolism and glyoxylate metabolism and deficiency of this enzyme is believed to be the cause of primary hyperoxaluria type 2 (PH2). The pH optima and kinetic parameters of D-GDH and GR in human liver have been determined and assays developed for their measurement. Maximal activities were observed at pH 6.0, 8.0 and 7.6 for the D-GDH forward, D-GDH reverse and GR reactions, respectively. The apparent Km values for the substrates in these reactions were as follows: D-GDH forward reaction, 0.5 mmol/L hydroxypyruvate and 0.08 mmol/L NADPH; D-GDH reverse reaction, 20 mmol/L D-glycerate and 0.03 mmol/L NADP and for the GR reaction 1.25 mmol/L glyoxylate and 0.33 mmol/L NADPH. The forward D-GDH and GR assays were adopted for routine use, the low activity of the reverse D-GDH reaction being of little use for routine analyses. D-GDH and GR activity in 13 normal livers ranged from 350–940 nmol per min per mg protein (median 547) and 129–209 nmol per min per mg protein (median 145), respectively. D-GDH activity in kidney, lymphocytes and fibroblasts fell within the range of values seen in the liver but GR activity was approximately 30% in the kidney and barely detectable in lymphocytes and fibroblasts. Analysis of liver and lymphocyte samples from patients with PH2 showed that GR activity was either very low or undetectable while D-GDH activity was reduced in liver but within the normal range in lymphocytes. These results suggest that there is more than one enzyme with D-GDH activity in human tissues but only one of these has significant GR activity. We conclude that a definitive diagnosis of PH2 requires measurement of GR and D-GDH in a liver biopsy.
Serum Sialic Acid, a Reputed Cardiovascular Risk Factor, is Elevated in South Asian Men Compared to European Men
Authors: Crook M , Kerai P , Andrews V , Lumb P , Swaminathan R 
Published: February 2014

Serum total sialic acid (TSA) has recently been reported as a cardiovascular risk factor, but whether there are racial differences is not known. One hundred and twenty-four healthy young subjects (62 women and 62 men) were studied. Their age was 20.7 [0.9] years and they were matched for body mass index (BMI). Sixty-eight were of South Asian origin (37 women and 31 men) and 56 (25 women and 31 men) were European. Mean (SD) serum TSA was significantly higher in the South Asian men than the age-matched European men (74.3 [12.3]mg/dL versus 68.2 [13.0]mg/dL, P = 0.0198). In addition, serum TSA was significantly higher in South Asian women compared with European men (71.6 [8.9]mg/dL versus 68.2 [13.0]mg/dL, P = 0.0352). Finally, serum TSA was significantly higher in European women compared with European men (76.0 [13.1]mg/dL versus 69.2 [130]mg/dL, P = 0008). We conclude that serum TSA may be worth measuring in different racial groups and also may be useful to assess individuals at risk of cardiovascular disease. Large prospective studies may help to explain why serum TSA is a reputed cardiovascular risk factor and shows racial differences.
Clinical and Biochemical Determinants of Plasma Lipid Peroxide Levels in Type 2 Diabetes
Authors: Lawrence J R , Campbell G R , Barrington H , Malcolm E A , Brennan G , Wiles D H , Paterson J R 
Published: February 2014

The enhanced risk and increased severity of atheroma in diabetes is well recognized but, as yet, incompletely explained. A cross-sectional study of vascular disease risk factors in a group of type 2 diabetic patients from South West Scotland has revealed an association between glycaemic control, assessed by HbA1 level and plasma lipid peroxides measured by a specific high-performance liquid chromatography method. Duration of diabetes appeared to be a subsidiary contributor to lipid peroxidation. We suggest this evidence supports the importance of glycaemic control in modulating glyco-oxidative mechanisms probably crucial to production of diabetic complications. Atherosclerosis prevention in diabetes may hinge on exemplary simultaneous control of both hyperglycaemia and hyperlipidaemia.
Clinical Usefulness of Bone Alkaline Phosphatase in Osteoporosis
Authors: Kyd P A , De Vooght K , Kerkhoff F , Thomas E , Fairney A 
Published: February 2014

We have evaluated two commercial assays for serum bone specific alkaline phosphatase (bALP) as a marker of bone turnover in a group of 35 postmenopausal women with osteoporosis during their first year of treatment with the anti-resorptive drug, alendronate. The immunoradiometric assay (bALP-I) measured protein mass, whereas the immunocapture assay (bALP-E) measured activity. Before treatment, bALP values with both methods were within the postmenopausal reference ranges. Treatment with alendronate produced a decrease in bALP after 3 months, reaching a plateau after 6 months: for bALP-I a mean change of −34%, ( P < 00001), bALP-E, −19% ( P < 0·001), and total ALP, −19% ( P < 00001). The decrease was significant in 53% (bALP-I) and 31% (bALP-E) of patients. The ratio of serum bALP-E/bALP-I in patients was not constant but rose after therapy with alendronate. Neither baseline bALP, nor the per cent change in bALP after 6 months, correlated with bone mineral density (BMD) change after 1 year at either lumbar spine or femoral neck. We conclude that bALP-I appeared to be a more sensitive marker of the suppression of bone turnover by alendronate than did bALP-E, but that neither was useful in the detection of osteoporosis, nor the prediction of individual BMD response to alendronate therapy.
Influence of Anti-Insulin Antibodies on Insulin Immunoassays in the Autoimmune Insulin Syndrome
Authors: Casesnoves Adela , Mauri Montserrat , Dominguez José R , Alfayate Rocío , Picó Antonio M 
Published: February 2014

The autoimmune insulin syndrome (AIS) is a rare, benign syndrome characterized by hyperinsulinaemia and hypoglycaemia associated with the presence of autoantibodies to insulin in patients who have not been treated with insulin. We report here the case of a 52-year-old patient with recurrent attacks of severe postprandial hypoglycaemia and we also present the effect of anti-insulin antibodies on insulin immunoassays. The patient was submitted to the following diagnostic tests: 5-h oral glucose tolerance test (OGTT), a prolonged 72-h fast and an insulin tolerance test (ITT). Serum glucose, total and free insulin, C-peptide, proinsulin, insulin antibodies and other autoantibodies were measured. Insulin concentrations were measured by two methods: a double antibody radioimmunoassay (RIA) and an immunoradiometric assay (IRMA). Insulin concentration measured by RIA was extremely high in the OGTT and 72-h fast. In contrast, insulin concentrations measured by IRMA were between 120 and 888 pmol/L in the OGTT and between 37 and 133 pmol/L during the 72-h fast. Fasting free-insulin concentrations measured by RIA were between 2224 and 2669 pmol/L, whereas free-insulin concentrations measured by IRMA ranged between 93 and 237 pmol/L. Total insulin concentrations measured by RIA and IRMA were 57615 and 94021 pmol/L, respectively. The C-peptide concentrations were moderately high in the three tests. Serum insulin antibody concentrations were extremely high (62–71%), compared with less than 3% in normal serum samples. In conclusion, the high insulin concentrations measured by RIA were caused by insulin autoantibodies. However, insulin concentrations measured by IRMA were not influenced by them. We conclude that IRMA is the more accurate method for measuring insulin concentrations in such cases.
Hypocholesterolaemia in a Hospital Population
Authors: Crook M A , Velauthar U , Moran L , Griffiths W 
Published: February 2014

The purpose of this study was to observe the prevalence of hypocholesterolaemia in a hospital population and also the causes and clinical outcome of this condition. Fifty-seven patients were found with a plasma cholesterol of ≤3·0 mmol/L, which was less than 0·50% of all plasma cholesterol requests; there were 39 men and 18 women ( P<0·05, Chi-squared test). The mean age was 53·8 [21·3] (range 3–83 years). The mean plasma cholesterol concentration was 2·28 [0·56] mmol/L (1·16–3·0) and the mean triglyceride concentration was 1·58 [1·09] mmol/L (0·49–7·35). There was a significant correlation between plasma cholesterol concentration and plasma albumin (Rs = 0·48, P < 0·01) and between plasma total protein concentration (Rs = 0·49, P < 0·01). However, there was no relationship between the concentrations of plasma cholesterol and triglyceride (Rs = −0·10, P > 0·05). Eighteen per cent of patients with hypocholesterolaemia died during their hospitalization. Thirty-nine per cent of those who had a plasma cholesterol of ≤2·0 mmol/L died whereas 71% of those who had a plasma cholesterol concentration of < 1·5 mmol/L died. Hypocholesterolaemia was more commonly seen in the intensive care unit and in post-operative patients, those with malignancy, sepsis, acute myocardial infarction, those who had inflammatory bowel disease and diabetics on insulin. Hypocholesterolaemia may be a useful predictor of mortality in hospital patients.
Faecal Elastase 1: A Marker of Exocrine Pancreatic Insufficiency in Cystic Fibrosis
Authors: Phillips I J , Rowe D J , Dewar P , Connett G J 
Published: February 2014

Pancreatic elastase 1 (E1), a digestive protease, is synthesized by the acinar cells of the pancreas. Using an enzyme-linked immunosorbent assay, we evaluated stool E1 levels in the following groups of patients: Specimens submitted for occult blood examination from 20 adults, over 3 consecutive days, to assess the inter-day variability in E1 excretion. There were no symptoms suggestive of pancreatic insufficiency in this group. The mean E1 concentration over all samples was 457 μg E1/g stool (range 124–1683). The intra-assay variation was 6·4% ( n = 14) and the inter-assay variation was 8·8% ( n = 12). The mean intra-patient variation was 17%. Cystic fibrosis (CF) patients. Eight patients had E1 levels in the reference range (>200 μg E1/g stool). The remaining 25 patients had undetectable E1 levels. A control group of children presenting with unexplained bronchiectasis and/or recurrent respiratory infections and no symptoms of pancreatic dysfunction. The mean E1 concentration in the group was 519 μg E1/g stool (range 139–1941). There was no significant difference in E1 concentrations between the two non-CF groups, nor between the pancreatic-sufficient CF patients when compared with both non-CF groups. There was a significant difference between the pancreatic-sufficient and -insufficient CF groups ( P < 0·001) using the Mann—Whitney U test. All fifteen CF patients who were ΔF508 homozygotes had undetectable E1. It may be possible to relate CF genotype to the presence or absence of E1 and to the degree of pancreatic insufficiency. Measurement of faecal E1 in children with CF appears to differentiate them into a group of children with normal pancreatic function and a larger group with severe insufficiency.
Post-partum hemorrhage and malpractice claims: What can we learn from the findings of placental examination and endometrial curettage? A retrospective analysis of surgical pathology reports
Authors: Marchetti Daniela , Vellone Valerio , Dhimitri Ollga , Fulcheri Ezio 
Published: February 2014

Objective This study reviews the surgical pathology reports of post-partum hemorrhages to support clinicians in malpractice litigation and, potentially, to enhance pregnancy-related diagnoses. Study design This work is a retrospective study of surgical pathology reports of term pregnancies between January 2000 and January 2012 selected from the Surgical Pathology database of the I.R.C.C.S Azienda Ospedaliera Universitaria San Martino-IST (Istituto Nazionale per la Ricerca sul Cancro, Genoa). Results Ninety-five revision reports were identified (0.22% “placenta accrete,” 0.46% “non-accreta placental tissue retention,” and 0.31% “no placental fragments retention”). Secondary post-partum hemorrhages occurred in 0.3%, and primary PPH occurred in 0.05%, regardless of the group examined. Both types of PPH were most often associated with vaginal deliveries (58%). The most frequent endometrial finding was post-partum endometritis (43%). The entire placenta was submitted to the pathologist in 22/95 cases (23%). Hypermaturity and/or villous immaturity were the main histological patterns. Conclusions This review supports the hypothesis that the pathological placenta abnormalities observed, rather than underlying myometrium abnormalities, may underlie the contractile failure and the incomplete removal of the placenta. For these reasons, the authors emphasized the importance of investigating the placenta in cases of complicated deliveries not associated with PPH to support clinicians in malpractice claims.