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1.
Phys Chem Chem Phys ; 17(32): 20830-9, 2015 Aug 28.
Article in English | MEDLINE | ID: mdl-26214614

ABSTRACT

Relative strengths of surface interaction for individual carbon atoms in acyclic and cyclic hydrocarbons adsorbed on alumina surfaces are determined using chemically resolved (13)C nuclear magnetic resonance (NMR) T1 relaxation times. The ratio of relaxation times for the adsorbed atoms T1,ads to the bulk liquid relaxation time T1,bulk provides an indication of the mobility of the atom. Hence a low T1,ads/T1,bulk ratio indicates a stronger surface interaction. The carbon atoms associated with unsaturated bonds in the molecules are seen to exhibit a larger reduction in T1 on adsorption relative to the aliphatic carbons, consistent with adsorption occurring through the carbon-carbon multiple bonds. The relaxation data are interpreted in terms of proximity of individual carbon atoms to the alumina surface and adsorption conformations are inferred. Furthermore, variations of interaction strength and molecular configuration have been explored as a function of adsorbate coverage, temperature, surface pre-treatment, and in the presence of co-adsorbates. This relaxation time analysis is appropriate for studying the behaviour of hydrocarbons adsorbed on a wide range of catalyst support and supported-metal catalyst surfaces, and offers the potential to explore such systems under realistic operating conditions when multiple chemical components are present at the surface.

2.
Meat Sci ; 103: 68-74, 2015 May.
Article in English | MEDLINE | ID: mdl-25625941

ABSTRACT

The objective of this study was to evaluate the use of blood lactate concentration as an objective measure of beef cattle temperament and determine if the temperament of steers affected growth rate and tenderness of beef steaks. Angus×Simmental steers (n=154) were evaluated for blood lactate (BL), exit velocity (EV) and chute score (CS), and humanely harvested. Carcass characteristics were assessed and loin samples were obtained for tenderness evaluation. All measures of the temperament were significantly correlated to each other (r=0.14-0.47; P≤0.04). Steaks from steers in the medium BL classification were significantly more tender than steaks from steers from the high BL classification. The steers with faster EV tended to result in steaks with higher shear force values (P=0.07). The steers classified as fast growing resulted in steaks with lower shear force values (P=0.02) compared to steaks from steers classified as slow growing. Results suggest that the temperament contributes to variations in growth rate, blood lactate, and tenderness.


Subject(s)
Abattoirs , Behavior, Animal , Growth , Lactic Acid/blood , Red Meat/analysis , Stress, Mechanical , Temperament , Animal Welfare , Animals , Breeding , Cattle , Humans , Male , Movement
3.
Microbes Infect ; 17(4): 304-10, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25522934

ABSTRACT

Inflammatory bowel disease (IBD) is characterised by an inappropriate chronic immune response against resident gut microbes. This may be on account of distinct changes in the gut microbiota termed as dysbiosis. The role of fungi in this altered luminal environment has been scarcely reported. We studied the fungal microbiome in de-novo paediatric IBD patients utilising next generation sequencing and compared with adult disease and normal controls. We report a distinct difference in fungal species with Ascomycota predominating in control subjects compared to Basidiomycota dominance in children with IBD, which could be as a result of altered tolerance in these patients.


Subject(s)
Fungi/pathogenicity , Inflammatory Bowel Diseases/microbiology , Intestinal Mucosa/microbiology , Microbiota/genetics , Adult , Child , Child, Preschool , Fungi/classification , Fungi/genetics , Humans , Inflammatory Bowel Diseases/genetics
4.
J Dairy Sci ; 94(1): 361-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21183046

ABSTRACT

Adipose tissue metabolism is an essential factor in establishment of a successful lactation, and we have a good understanding of changes in metabolic flux in relation to lactation, parity, and diet. However, the mechanisms of control of flux are less well understood. To continue our investigations into the control of adipose tissue metabolism, we conducted a transcriptomic analysis of adipose tissue of dairy cattle in late pregnancy and early lactation. Our objective was to determine the changes in gene expression in adipose tissue between 30 d prepartum and 14 d in milk in first-lactation animals, and to determine if changes in expression were related to practical production variables. Animals were Holstein heifers fed the same diet to National Research Council requirements, and adipose tissue was biopsied at 30 d prepartum and 14 DIM. Total RNA was extracted and used to determine gene expression on a bovine gene array. Genes that code for proteins controlling fatty acid transport were highly expressed including fatty acid binding proteins (FABP4 and FABP5) and lipoprotein lipase. Among those genes increasing in expression were those controlling lipolysis, including ADRB2 (52%) and LIPE (23%). Many genes coding for enzymes controlling lipogenesis decreased, including SREBP (-25%), TSHSP14 (-30.8%), LPL (-48.4%), and ACACA (-63.9%). This gene expression array analysis in adipose tissue of lactating dairy cattle identifies several key genes that are components of the adaptation to lactation that can be incorporated into models of nutritional efficiency and may be amenable to genetic or dietary manipulation.


Subject(s)
Adipose Tissue/metabolism , Cattle/physiology , Gene Expression Regulation , Lactation/physiology , Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Animals , Cattle/metabolism , Diet/veterinary , Fatty Acid Transport Proteins/genetics , Female , Gene Expression Profiling/veterinary , Lipogenesis/genetics , Lipolysis/genetics , Lipoprotein Lipase/genetics , Pregnancy
5.
Australas Radiol ; 45(3): 291-7, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11531751

ABSTRACT

The equivalent sensitivity of non-contrast computed tomography (NCCT) and intravenous urography (IVU) in the diagnosis of suspected ureteric colic has been established. Approximately 50% of patients with suspected ureteric colic do not have a nephro-urological cause for pain. Because many such patients require further imaging studies, NCCT may obviate the need for these studies and, in so doing, be more cost effective and involve less overall radiation exposure. The present study compares the total imaging cost and radiation dose of NCCT versus IVU in the diagnosis of acute flank pain. Two hundred and twenty-four patients (157 men; mean age 45 years; age range 19-79 years) with suspected renal colic were randomized either to NCCT or IVU. The number of additional diagnostic imaging studies, cost (IVU A$136; CTU A$173), radiation exposure and imaging times were compared. Of 119 (53%) patients with renal obstruction, 105 had no nephro-urological causes of pain. For 21 (20%) of these patients an alternative diagnosis was made at the initial imaging, 10 of which were significant. Of 118 IVU patients, 28 (24%) required 32 additional imaging tests to reach a diagnosis, whereas seven of 106 (6%) NCCT patients required seven additional imaging studies. The average total diagnostic imaging cost for the NCCT group was A$181.94 and A$175.46 for the IVU group (P < 0.43). Mean radiation dose to diagnosis was 5.00 mSv (NCCT) versus 3.50 mSv (IVU) (P < 0.001). Mean imaging time was 30 min (NCCT) versus 75 min (IVU) (P < 0.001). Diagnostic imaging costs were remarkably similar. Although NCCT involves a higher radiation dose than IVU, its advantages of faster diagnosis, the avoidance of additional diagnostic imaging tests and its ability to diagnose other causes makes it the study of choice for acute flank pain at Christchurch Hospital.


Subject(s)
Flank Pain/etiology , Tomography, X-Ray Computed , Urinary Calculi/diagnostic imaging , Urography , Adult , Aged , Costs and Cost Analysis , Female , Flank Pain/diagnostic imaging , Humans , Male , Middle Aged , Radiation Dosage , Tomography, X-Ray Computed/economics , Urography/economics
6.
Apoptosis ; 6(4): 299-314, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11445672

ABSTRACT

During the course of a screening procedure designed to isolate gene products that mediate avian lymphocyte apoptosis, a 1070 bp cDNA encoding a 242 amino acid protein, cThy28 (GenBank accession number U34350), was isolated. Based on the deduced amino acid sequence, cThy28 is a conserved protein that shares greater than 90% amino acid similarity with several putative mammalian homologues. A structural analysis of the protein suggests that is a nuclear-localized, phosphoprotein with potential glycosylation and myristolation sites. Compared to other non-lymphoid tissues, the cThy28 protein and its transcript are present in immune organs at elevated levels. When the expression of cThy28 was analyzed in cultured bursal lymphocytes undergoing apoptosis, the cellular levels of this protein and its transcript declined and underwent degradative processes as a function of the apoptotic process. Treatment of lymphocytes with phorbol esters inhibited apoptosis and protected the cellular levels of the cThy28 protein and its transcript from undergoing this degradative process; however, analysis of transcripts of a "housekeeping" gene, GAPDH (glyceraldehyde phosphate dehydrogenase), revealed a similar response to this apoptosis treatment regimen. Thus, the apoptotic-mediated alterations in cThy28 expression and its role in lymphocyte function remain undefined; however, the potential task of this gene in apoptosis may be related to the putative functions of the cThy28 mammalian homologues identified in this report.


Subject(s)
Lymphocytes/metabolism , Nuclear Proteins/biosynthesis , Amino Acid Sequence , Animals , Apoptosis , Avian Proteins , Blotting, Northern , Blotting, Western , Bursa of Fabricius/metabolism , Cells, Cultured , Chickens , Densitometry , Gene Expression , Humans , In Situ Nick-End Labeling , Molecular Sequence Data , Nuclear Proteins/genetics , Phorbol Esters/pharmacology , Sequence Homology, Amino Acid
7.
J Biol Chem ; 276(36): 33952-63, 2001 Sep 07.
Article in English | MEDLINE | ID: mdl-11423539

ABSTRACT

Skp1 is a subunit of the SCF-E3 ubiquitin ligase that targets cell cycle and other regulatory factors for degradation. In Dictyostelium, Skp1 is modified by a pentasaccharide containing the type 1 blood group H trisaccharide at its core. To address how the third sugar, fucose alpha1,2-linked to galactose, is attached, a proteomics strategy was applied to determine the primary structure of FT85, previously shown to copurify with the GDP-Fuc:Skp1 alpha 1,2-fucosyltransferase. Tryptic-generated peptides of FT85 were sequenced de novo using Q-TOF tandem mass spectrometry. Degenerate primers were used to amplify FT85 genomic DNA, which was further extended by a novel linker polymerase chain reaction method to yield an intronless open reading frame of 768 amino acids. Disruption of the FT85 gene by homologous recombination resulted in viable cells, which had altered light scattering properties as revealed by flow cytometry. FT85 was necessary and sufficient for Skp1 fucosylation, based on biochemical analysis of FT85 mutant cells and Escherichia coli that express FT85 recombinantly. FT85 lacks sequence motifs that characterize all other known alpha 1,2-fucosyltransferases and lacks the signal-anchor sequence that targets them to the secretory pathway. The C-terminal region of FT85 harbors motifs found in inverting Family 2 glycosyltransferase domains, and its expression in FT85 mutant cells restores fucosyltransferase activity toward a simple disaccharide substrate. Whereas most prokaryote and eukaryote Family 2 glycosyltransferases are membrane-bound and oriented toward the cytoplasm where they glycosylate lipid-linked or polysaccharide precursors prior to membrane translocation, the soluble, eukaryotic Skp1-fucosyltransferase modifies a protein that resides in the cytoplasm and nucleus.


Subject(s)
Cell Cycle Proteins/metabolism , Cytoplasm/enzymology , Dictyostelium/enzymology , Fucosyltransferases/chemistry , Golgi Apparatus/enzymology , Amino Acid Sequence , Animals , Base Sequence , Blotting, Western , Cell Nucleus/metabolism , Chromatography, Gel , Cytoplasm/metabolism , Electrophoresis, Polyacrylamide Gel , Escherichia coli/metabolism , Flow Cytometry , Fucosyltransferases/genetics , Introns , Light , Mass Spectrometry , Models, Genetic , Molecular Sequence Data , Mutation , Open Reading Frames , Polymerase Chain Reaction , Protein Structure, Tertiary , Recombinant Proteins/metabolism , S-Phase Kinase-Associated Proteins , Scattering, Radiation , Sequence Homology, Amino Acid , Galactoside 2-alpha-L-fucosyltransferase
8.
Clin Nutr ; 19(3): 191-5, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10895110

ABSTRACT

AIMS: The primary objective was to estimate prevalence of malnutrition on admission to four hospitals. Secondary objectives included assessing the relationship between nutritional status and length of hospital stay, numbers of new prescriptions, new infections and disease severity. METHODS: We entered eligible patients according to predefined quotas for elective and emergency admissions to 23 specialties. We measured height, weight, Body Mass Index and anthropometrics, and recorded history of unintentional weight loss. Patients who had lost > or = 10% of their body weight, had a Body Mass Index <20, or had a Body Mass Index <20 with one anthropometric measurement <15th centile were considered malnourished. RESULTS: Of 1611 eligible patients, 761 did not participate; 269 were too ill; 256 could not be weighed; and 236 refused consent. Eight hundred and fifty were subsequently evaluated. Prevalence of malnutrition on admission was 20%. Length of stay, new prescriptions and infections and disease severity were significantly higher in the malnourished. CONCLUSIONS: One patient in every five admitted to hospital is malnourished. Although this figure is unacceptably high, it may underestimate true prevalence. Malnutrition was associated with increased length of stay, new prescriptions and infections. Malnutrition may also have contributed to disease severity.


Subject(s)
Length of Stay , Nutrition Assessment , Nutrition Disorders/epidemiology , Patient Admission , Adolescent , Adult , Aged , Aged, 80 and over , Cross Infection/complications , Cross Infection/metabolism , England/epidemiology , Female , Hospitals, General , Humans , Male , Middle Aged , Nutrition Disorders/complications , Nutrition Disorders/diagnosis , Nutritional Status , Prevalence , Severity of Illness Index
9.
Hum Genet ; 105(6): 567-76, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10647891

ABSTRACT

We have used a new method for binning minisatellite alleles (semi-automated allele aggregation) and report the extent of population diversity detectable by eleven minisatellite loci in 2,689 individuals from 19 human populations distributed widely throughout the world. Whereas population relationships are consistent with those found in other studies, our estimate of genetic differentiation (F(st)) between populations is less than 8%, which is lower than comparative estimates of between 10%-15% obtained by using other sources of polymorphism data. We infer that mutational processes are involved in reducing F(st) estimates from minisatellite data because, first, the lowest F(st) estimates are found at loci showing autocorrelated frequencies among alleles of similar size and, second, F(st) declines with heterozygosity but by more than predicted assuming simple models of mutation. These conclusions are consistent with the view that minisatellites are subject to selective or mutational constraints in addition to those expected under simple step-wise mutation models.


Subject(s)
Genetics, Population , Minisatellite Repeats/genetics , Mutation , Alleles , Heterozygote , Homozygote , Humans , Models, Genetic
10.
Aliment Pharmacol Ther ; 12(2): 135-40, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9692687

ABSTRACT

AIM: To investigate the efficacy of omeprazole 20 mg o.m. as primary prophylaxis against non-steroidal anti-inflammatory drug (NSAID)-associated ulcer disease or dyspeptic symptoms. METHODS: A parallel group study compared patients randomized to receive omeprazole 20 mg o.m. or placebo as co-therapy with on-going NSAID treatment, over 6 months, in 19 specialist centres in Ireland, Hungary, France, the UK and the USA. One hundred and sixty-nine patients taking NSAIDs regularly, chronically and above defined minimum doses entered the trial. The main outcome measure was the development of gastric or duodenal ulcers detected endoscopically, the development of multiple erosions in the stomach or duodenum, or the onset of moderate or severe dyspeptic symptoms. RESULTS: The estimated probability of remaining free of these end-points for 6 months for patients taking omeprazole was 0.78 compared to 0.53 for placebo (P = 0.004). Fourteen patients receiving placebo (16.5%) developed 15 ulcers, comprising nine gastric and six duodenal ulcers, compared to three patients (3.6%) receiving omeprazole (all gastric ulcers). Logistic regression analysis showed that older patients were less likely, whilst those with rheumatoid arthritis were more likely, to remain free of NSAID-associated problems. CONCLUSIONS: Omeprazole is an effective agent for gastroduodenal prophylaxis in patients taking NSAIDs. Its main effect is to reduce the rate of development of gastric and duodenal ulcers.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Anti-Ulcer Agents/therapeutic use , Duodenal Ulcer/prevention & control , Dyspepsia/prevention & control , Omeprazole/therapeutic use , Stomach Ulcer/prevention & control , Adolescent , Adult , Aged , Aged, 80 and over , Double-Blind Method , Duodenal Ulcer/chemically induced , Dyspepsia/chemically induced , Female , France , Humans , Hungary , Ireland , Logistic Models , Male , Middle Aged , Stomach Ulcer/chemically induced , United Kingdom , United States
13.
Thromb Haemost ; 79(2): 328-30, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9493585

ABSTRACT

A longitudinal study of 21 pregnant women has been undertaken using a variety of factor VII assays, including factor VIIa, to investigate the increase of factor VIIc. All assays demonstrated significant rises (p <0.001), most marked for factor VIIa (82%) and factor VIIc rabbit (81%). Smaller rises were seen for factor VIIc bovine (50%) and VII antigen (40%). Three indirect measures of activity state, factor VIIc rabbit:antigen, bovine:antigen and bovine:rabbit, provided conflicting data. Factor VIIa:antigen showed a significant increase of 36% (p <0.001). Within individual pregnancies the change in factor VIIc rabbit and antigen correlated with maternal weight gain (p < 0.05). Two activity state measures, bovine:rabbit and bovine:antigen, showed negative correlation with birthweight. The increases in both zymogen and in activity state appear to contribute to the factor VIIc rise. The extent of this rise appears to be influenced by maternal weight gain. Increased factor VII activation is associated with reduced foetal growth.


Subject(s)
Factor VII/analysis , Pregnancy/blood , Adult , Animals , Birth Weight , Body Weight , Cattle , Factor VIIa/analysis , Female , Humans , Infant, Newborn , Rabbits
14.
Dev Comp Immunol ; 21(5): 413-24, 1997.
Article in English | MEDLINE | ID: mdl-9397347

ABSTRACT

To further elucidate the cellular mechanisms that mediate programmed cell death in avian immune cells, differential display analysis was employed to identify differentially expressed genes in chicken thymocytes undergoing apoptosis. Primary cultures of thymocytes were treated with dexamethasone to activate apoptosis and RNA was isolated for differential display analysis. A differential display product designated A1 (479 bp) was identified. This display product was subcloned and induced expression of the genes was confirmed by ribonuclease protection analysis. Nucleotide sequence analysis of A1 revealed a putative 82 amino acid open reading frame that demonstrated limited homology with Bad, an apoptotic regulatory protein. Thus, A1 may represent the avian homolog of Bad.


Subject(s)
Apoptosis/genetics , Gene Expression Regulation , Amino Acid Sequence , Animals , Base Sequence , Cells, Cultured , Chickens , DNA, Complementary , Humans , Molecular Sequence Data , Ribonucleases/metabolism , Thymus Gland/cytology
15.
Thromb Res ; 85(6): 455-64, 1997 Mar 15.
Article in English | MEDLINE | ID: mdl-9101638

ABSTRACT

Although hormone replacement therapy (HRT) appears to protect women from ischaemic heart disease (IHD), its use is associated with increased factor clotting activity (VIIc), an independent risk factor for IHD. The nature of this factor VII rise was therefore examined in a cross-sectional study of 279 women aged between 40 and 65 years. Ninety-four were pre-menopausal, 44 were post-menopausal and taking HRT, whilst 141 were post-menopausal non-users. For those women on oestrogen-only HRT, the mean factor VIIc was 144%, compared to 130% for post-menopausal non-users, and 116% for those on combined HRT. These differences were significant (p = 0.01). Oestrogen-only users also had significantly higher mean levels of factor VIIa (3.3 ng/ml) compared to non-users (2.2 ng/ml) and those on oestrogen-progestogen HRT (2.2 ng/ml-p = 0.015). In contrast for factor VII antigen the mean values of the three groups were similar. Analysis of the age-regression slopes showed a significant age-related rise in factor VIIc of 1.2% per annum (p < 0.01) for post-menopausal non-users. There was a similar increase in factor VII antigen (2.1%) but no rise in factor VIIa. For all HRT users there was no change with age for any of the factor VII measures. Thus the age-related rise in factor VIIc appears to be due to an increase in factor VII zymogen alone, and taking HRT seems to abolish such a rise. In contrast, the increased factor VIIc seen with oestrogen-only HRT appears to be secondary to factor VII activation.


Subject(s)
Aging/metabolism , Antigens/metabolism , Estrogen Replacement Therapy , Factor VII/metabolism , Adult , Aged , Body Mass Index , Drug Therapy, Combination , Estrogens/administration & dosage , Estrogens/therapeutic use , Factor VIIa/metabolism , Female , Humans , Mass Screening , Menopause , Middle Aged , Myocardial Ischemia/epidemiology , Progestins/administration & dosage , Progestins/therapeutic use , Risk Factors
16.
Am J Hum Genet ; 58(5): 1017-24, 1996 May.
Article in English | MEDLINE | ID: mdl-8651262

ABSTRACT

The origins of aboriginal Australians and their relationship with New Guineans and neighboring Southeast Asians remains controversial. We have studied the alpha-globin haplotype composition of an aboriginal tribe from central Australia, to address some of the ambiguities of previous studies. Australians have a haplotype repertoire that is shared with New Guinea highlanders, a fact that strongly supports a common origin of these two populations. Further, Australians and New Guinea highlanders have a different set of alpha haplotypes from Southeast Asians and a lower genetic diversity. This, coupled with the presence of many locally specific central Australian haplotypes, suggests that much of the original diversity was lost in a population bottleneck prior to or during the early colonization of Sahul and that subsequent recovery of diversity has been accompanied by the generation of new haplotypes. These conclusions contrast with some previous genetic studies suggesting links between Australians, coastal New Guineans, and present-day Southeast Asians. Much of this discrepancy appears to be due to more recent Southeast Asian admixture on the north coast of Australia.


Subject(s)
Globins/genetics , Native Hawaiian or Other Pacific Islander/genetics , Australia , Genetics, Population , Haplotypes , Humans , New Guinea
17.
Thromb Haemost ; 72(5): 682-4, 1994 Nov.
Article in English | MEDLINE | ID: mdl-7900074

ABSTRACT

Long-term stability studies on the WHO second primary International Reference Preparation (IRP) for thromboplastin (human plain BCT/253) stored at -20 degrees C have been conducted for ten years. Three centres took part in the exercise using frozen normal and coumarinised plasma samples which were tested throughout. There has been no measurable change in the prothrombin time performance of the human plain IRP over the ten-year period. It can therefore be concluded that new IRP may continue to be calibrated against this preparation in accord with WHO recommendations.


Subject(s)
Thromboplastin/chemistry , Analysis of Variance , Calibration , Drug Stability , Humans , Prothrombin Time , Reference Standards , World Health Organization
18.
Can J Appl Physiol ; 19(1): 75-90, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8186764

ABSTRACT

The purpose of the study was to develop a minimum physical fitness standard for Canadian Forces personnel, 35 years and older, based on common criteria for physically demanding tasks. A random sample of 100 men and 76 women performed the Exercise Prescription (EXPRES) test and five physically demanding tasks that simulate common military tasks, while restricted, for safety reasons, to 90% maximal predicted heart rate. Results indicated poor predictive power, as variances ranged from 5 to 55% between EXPRES fitness scores and task performance. With approval from an expert panel, the 75th percentile score for each task was selected as the cutting criterion. The passing-group data were converted to Z-scores in order to determine the 5th percentile from each EXPRES item: these scores became the EXPRES fitness standard. The minimum fitness standard had a greater impact on women than on men but was representative of the passing groups for both sexes.


Subject(s)
Military Personnel , Physical Fitness , Adult , Age Factors , Canada , Discriminant Analysis , Exercise Tolerance/physiology , Female , Heart Rate/physiology , Humans , Male , Middle Aged , Muscle Contraction/physiology , Oxygen Consumption/physiology , Physical Fitness/physiology , Reference Standards , Regression Analysis , Reproducibility of Results , Sex Factors , Task Performance and Analysis
19.
Br J Haematol ; 86(1): 112-7, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8011518

ABSTRACT

One hundred and twenty-nine centres in the U.K. participated in a study to test the reliability of the three methods of correction for coagulometer effects on international normalized ratios (INR). Results from 37 centres which tested three warfarinized plasmas by the manual method were taken as the 'true' INR for the assessment of coagulometers. 63 centres (11 manual and 52 using coagulometers) determined their local International Sensitivity Index (ISI) in a calibration exercise. This was performed with a set of 20 lyophilized plasma calibrants with certified manual prothrombin times for the thromboplastin used in the study. The following methods of INR derivation were compared by assessing the percentage deviation from the three INR values established by 37 manual users: I. No coagulometer correction, i.e. (local PT/reference manual normal PT)manual ISI II. Coagulometer ratio correction, i.e. (local coagulometer PT/local coagulometer MNPT)manual ISI III. Local system ISI, i.e. (local coagulometer PT/local coagulometer MNPT)local system ISI IV. System ISI, i.e. (local coagulometer PT/local coagulometer MNPT)system ISI The local system ISI with the plasma calibrants (method III) gave the most reliable correction (mean deviation from 'true' INR 4.87%). The method which gave the least was with the coagulometer ratio correction, i.e. the manual ISI and local coagulometer MNPT (mean 11.25%). The system ISI tested with ACL coagulometers gave less correction than the local ISI calibration. The local system calibration with lyophilized plasmas also avoids some of the constraints on conventional thromboplastin calibrations.


Subject(s)
Prothrombin Time , Warfarin/administration & dosage , Calibration , Humans , Reference Values , Reproducibility of Results
20.
Br J Haematol ; 85(2): 348-51, 1993 Oct.
Article in English | MEDLINE | ID: mdl-8280607

ABSTRACT

A close inter-relationship between raised factor VII clotting activity and elevated blood lipids, particularly serum triglycerides, is well established. A study of factor VII, its activation state and of plasma lipids has been undertaken in two groups of healthy middle-aged males to elucidate this mechanism. A control group with normal factor VII levels were closely matched for age and body-mass index with a second group with elevated levels. Factor VII assays, using rabbit and bovine thromboplastin and a factor VII Ag method, were employed. Triglycerides correlated with the rabbit factor VII thromboplastin assay and factor VII Ag (P < 0.05) but not with the bovine thromboplastin method. Higher HDL-cholesterol and apolipoprotein A-I levels were found in subjects with increased factor VII (P < 0.001) and appeared to be due to differences in alcohol consumption. Cholesterol levels were significantly higher with elevated factor VII. Differential testing suggests that higher factor VII is predominantly mediated through a rise in total VII, rather than an increase in its activity state.


Subject(s)
Factor VII/analysis , Lipids/blood , Adult , Antigens/analysis , Apolipoproteins/analysis , Cholesterol/blood , Factor VII/immunology , Factor VIIa/analysis , Humans , Male , Middle Aged , Triglycerides/blood
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