Nigel Lambert - Profile on Academia.edu (original) (raw)
Papers by Nigel Lambert
Norleg
Nutrition & Food Science, 1991
New Looks at Neglected Legumes
Nutrition & Food Science, 1989
Modified procedure for rapid purification of protein disulphide-isomerase from bovine liver
Biochemical Society Transactions, 1982
Chemical modification of essential residues in purified rat liver protein disulphide-isomerase
Biochemical Society Transactions, 1984
Assessing patients' preferences for treatments for angina using a modified repertory grid method
Soc Sci Med 60 2585 2595, Jun 1, 2005
A current popular theme in medicine concerns whether and how patients should be involved in treat... more A current popular theme in medicine concerns whether and how patients should be involved in treatment choice. Assuming patient involvement is desirable, how should one go about eliciting preferences? A variety of quantitative and qualitative methods exist that may be used for this purpose, one of which is the repertory grid method. This method involves eliciting constructs (reasons) for preferences through comparing sets of three options. This method allows the structured elicitation of the reasons behind individual preferences, but also, when used with generalised procrustes analysis (GPA), allows aggregation of individual data to reveal general preference patterns. In this study the repertory grid method was used to examine patient preferences for angina treatments with the goal of, first, gaining some understanding of general patterns of patient preference, and second, examining the likely utility of the technique in this setting. A sample of 21 patients with mild and stable angina from two general practices in Norfolk, UK was interviewed using the repertory grid method to elicit the constructs underlying their preferences amongst seven angina treatments (including 'no treatment'). Individualised questionnaires were then produced and sent to the patients for self-completion, which required rating the extent to which each construct was relevant for each treatment (scored on visual analogue rating scales). Analysis of the ratings, using GPA, showed that the constructs clustered around two dimensions: 'some treatment' versus 'no treatment', and drug treatment versus surgical treatment. While some treatment was generally preferred to no treatment, individuals varied in preference for drug treatments or surgical treatments. Although the latter were generally perceived as 'effective' they were also perceived, for example, as 'invasive', 'frightening', related to 'negative experiences', and being more appropriate for when symptoms are severe ('proportionate'). We consider the implications of these results for involving patients in choosing amongst treatments.
Treatment selection is now much more consumer driven than in the past. However, there is a need t... more Treatment selection is now much more consumer driven than in the past. However, there is a need to develop investigative methodological approaches that are sensitive to diVerences in patient preferences if full account is to be taken of what the patient sees as the best option in terms of diVerent possible treatments available for a particular condition. Previous attitude research has been criticised because it does not provide insight into reasons why people hold diVerent preferences or beliefs. A methodology is described which allows people to describe their concerns and values associated with diVerent treatment options in their own words. This is the repertory grid method of eliciting personal constructs used in conjunction with generalised Procrustes analysis (GPA). An example of the use of this methodology is provided, drawn from research directed towards understanding people's beliefs about genetic technologies. A possible application of the method to understanding treatment preferences related to type 2 diabetes is also discussed. It is concluded that the use of innovative methodologies is essential if our understanding of patient preferences regarding treatment options is to have a significant impact on patient quality of life. (Quality in Health Care 2001;10(Suppl I):i50-i54)
Health Expectations an International Journal of Public Participation in Health Care and Health Policy, Sep 1, 2010
Objective To use semi-structured interviews to ascertain patterns in patientsÕ expectations of he... more Objective To use semi-structured interviews to ascertain patterns in patientsÕ expectations of health care and the extent to which these expectations were met or not.
Food Chemistry, 1990
Cocosin, an 11S seed storage globulin flora coconut, has been purified and characterised by HPLC ... more Cocosin, an 11S seed storage globulin flora coconut, has been purified and characterised by HPLC gel filtration and anion-exchange chromatography. At least eight different subunit species have been identified. Despite this heterogeneity, cocosin crystallises very readily into forms typical of this class of protein. The molecular weight of the protein was in the range 250000-300 000. higher than the value of 208 000 previously ascribed. A subunit molecular weight of approximately 54000, together with the crystal symmetry, suggests that cocosin is a typical hexameric l l S globulin, and not a tetramer as was previously postulated.
Smoking cessation and vegetable consumption : reducing cancer through communication?
Biochemical Journal
1. Protein disulphide-isomerase from bovine liver was purified to homogeneity as judged by sodium... more 1. Protein disulphide-isomerase from bovine liver was purified to homogeneity as judged by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, twodimensional electrophoresis and N-terminal amino acid analysis. The preparative procedure, a modification of that of Carmichael, J. Biol. Chem. 252, 7163-71671, is much faster and higher-yielding than previous procedures, and the final purified material is of higher specific activity. 2. The enzyme has Mr 57000 as determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, both in the presence and in the absence of thiol compounds. Gel-filtration studies on Sephadex G-200 indicate an M, of 107000, suggesting that the native enzyme is a homodimer with no interchain disulphide bonds. Ultracentrifugation studies give a sedimentation coefficient of 3.5S, implying that the enzyme sediments as the monomer. 3. The isoelectric point, in the presence of 8 M-urea, is 4.2, and some microheterogeneity is detectable. 4. The amino acid composition is comparable with previous analyses of this enzyme from bovine liver and of other preparations of thiol: protein disulphide oxidoreductases whose relation to protein disulphide-isomerase has been controversial. The enzyme contains a very high proportion of Glx + Asx residues (27%). The N-terminal residue is His. 5. The pure enzyme has a very small carbohydrate content, determined as 0.5-1.0% by the phenol/H2SO4 assay. Unless specific steps are taken to remove it, the purified enzyme contains a small amount (5 mol/mol of enzyme) of Triton X-100 carried through the purification.
Poor diet and smoking : the big killers : comparing health education in two hazard domains
British Food Journal
Encouraging the UK public to quit smoking has been a public health feature for over a century to ... more Encouraging the UK public to quit smoking has been a public health feature for over a century to a greater or lesser degree. Persuading people to consume five or more portions of fruits and vegetables is a far newer health policy, with a history of only some ten years. The article compares the established anti-smoking campaign with that of the
The latency of rat liver microsomal protein disulfide-isomerase
Biochemical Journal
ABSTRACT
Protocol for purification of pea storage proteins and characterization of their aggregation state
Biochemical Society Transactions, 1986
The dissociation of pea 11S storage protein by salt, as measured by light scattering
Biochemical Society Transactions, 1987
Effect of ethoxyquin on glutathione levels and peroxidisability of rat liver membranes
Biochemical Society transactions, 1996
... of rat liver membranes. GEOFFREY W. PLUMB, NIGEL LAMBERT, STEPHEN J.CHAMBERS, HELEN L. CLARKE... more ... of rat liver membranes. GEOFFREY W. PLUMB, NIGEL LAMBERT, STEPHEN J.CHAMBERS, HELEN L. CLARKE, MARGARET M. MANSON, GORDON NEAL and GARY WILLIAMSON. Department of Food Molecular Biochemistry ...
Influence of phenolics on protein binding to the antioxidant responsive element (ARE)
Biochemical Society transactions, 1996
Purification of a cytosolic enzyme from human liver with phospholipid hydroperoxide glutathione peroxidase activity
The International journal of biochemistry
Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is a selenoprotein which inhibits perox... more Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is a selenoprotein which inhibits peroxidation of microsomes. The human enzyme, which may play an important role in protecting the cell from oxidative damage, has not been purified or characterized. PHGPx was isolated from human liver using ammonium sulphate fractionation, affinity chromatography on bromosulphophthalein-glutathione-agarose, gel filtration on Sephadex G-50, anion exchange chromatography on Mono Q resin and high resolution gel filtration on Superdex 75. The protein was purified about 112,000-fold, and 12 micrograms was obtained from 140 g of human liver with a 9% yield. PHGPx was active on hydrogen peroxide, cumene hydroperoxide, linoleic acid hydroperoxide and phosphatidylcholine hydroperoxide. The molecular weight, as estimated from non-denaturing gel filtration, was 16,100. The turnover number (37 degrees C, pH 7.6) on (beta-(13-hydroperoxy-cis-9, trans-11-octadecadienoyl)-gamma-palmitoyl)-L-alpha-phosphatid...
Evaluation of the antioxidant properties of food extracts
Biochemical Society transactions, 1995
The Biochemical journal, 1983
Protein disulphide-isomerase was purified to homogeneity from rat liver by a rapid high-yielding ... more Protein disulphide-isomerase was purified to homogeneity from rat liver by a rapid high-yielding procedure. Structural properties of the pure enzyme were very similar to those of the bovine liver enzyme purified by the same method. The purified rat liver enzyme was subjected to two-dimensional gel electrophoresis in the presence and in the absence of microsomal membranes, and shown to co-electrophorese with a major acidic polypeptide clearly identifiable in the two-dimensional electrophoretic profile of microsomal membranes. This identification was confirmed by peptide 'mapping' of the pure enzyme and of the defined spot from a two-dimensional electrophoresis gel.
The Biochemical journal, 1983
The protein disulphide-bond isomerization activity of highly active homogeneous protein disulphid... more The protein disulphide-bond isomerization activity of highly active homogeneous protein disulphide-isomerase (measured by re-activation of 'scrambled' ribonuclease) is enhanced by EDTA and by phosphate buffers. As shown for previous less-active preparations, the enzyme has a narrow pH optimum around pH 7.8 and requires the presence of either a dithiol or a thiol. The dithiol dithiothreitol is effective at concentrations 100-fold lower than the monothiols reduced glutathione and cysteamine. The enzyme follows Michaelis-Menten kinetics with respect to these substrates; Km values are 4,620 and 380 microM respectively. The enzyme shows apparent inhibition by high concentrations of thiol or dithiol compounds (greater than 10 X Km), but the effect is mainly on the extent of reaction, not the initial rate. This is interpreted as indicating the formation of significant amounts of reduced ribonuclease in these more reducing conditions. The purified enzyme will also catalyse net reduc...
Norleg
Nutrition & Food Science, 1991
New Looks at Neglected Legumes
Nutrition & Food Science, 1989
Modified procedure for rapid purification of protein disulphide-isomerase from bovine liver
Biochemical Society Transactions, 1982
Chemical modification of essential residues in purified rat liver protein disulphide-isomerase
Biochemical Society Transactions, 1984
Assessing patients' preferences for treatments for angina using a modified repertory grid method
Soc Sci Med 60 2585 2595, Jun 1, 2005
A current popular theme in medicine concerns whether and how patients should be involved in treat... more A current popular theme in medicine concerns whether and how patients should be involved in treatment choice. Assuming patient involvement is desirable, how should one go about eliciting preferences? A variety of quantitative and qualitative methods exist that may be used for this purpose, one of which is the repertory grid method. This method involves eliciting constructs (reasons) for preferences through comparing sets of three options. This method allows the structured elicitation of the reasons behind individual preferences, but also, when used with generalised procrustes analysis (GPA), allows aggregation of individual data to reveal general preference patterns. In this study the repertory grid method was used to examine patient preferences for angina treatments with the goal of, first, gaining some understanding of general patterns of patient preference, and second, examining the likely utility of the technique in this setting. A sample of 21 patients with mild and stable angina from two general practices in Norfolk, UK was interviewed using the repertory grid method to elicit the constructs underlying their preferences amongst seven angina treatments (including 'no treatment'). Individualised questionnaires were then produced and sent to the patients for self-completion, which required rating the extent to which each construct was relevant for each treatment (scored on visual analogue rating scales). Analysis of the ratings, using GPA, showed that the constructs clustered around two dimensions: 'some treatment' versus 'no treatment', and drug treatment versus surgical treatment. While some treatment was generally preferred to no treatment, individuals varied in preference for drug treatments or surgical treatments. Although the latter were generally perceived as 'effective' they were also perceived, for example, as 'invasive', 'frightening', related to 'negative experiences', and being more appropriate for when symptoms are severe ('proportionate'). We consider the implications of these results for involving patients in choosing amongst treatments.
Treatment selection is now much more consumer driven than in the past. However, there is a need t... more Treatment selection is now much more consumer driven than in the past. However, there is a need to develop investigative methodological approaches that are sensitive to diVerences in patient preferences if full account is to be taken of what the patient sees as the best option in terms of diVerent possible treatments available for a particular condition. Previous attitude research has been criticised because it does not provide insight into reasons why people hold diVerent preferences or beliefs. A methodology is described which allows people to describe their concerns and values associated with diVerent treatment options in their own words. This is the repertory grid method of eliciting personal constructs used in conjunction with generalised Procrustes analysis (GPA). An example of the use of this methodology is provided, drawn from research directed towards understanding people's beliefs about genetic technologies. A possible application of the method to understanding treatment preferences related to type 2 diabetes is also discussed. It is concluded that the use of innovative methodologies is essential if our understanding of patient preferences regarding treatment options is to have a significant impact on patient quality of life. (Quality in Health Care 2001;10(Suppl I):i50-i54)
Health Expectations an International Journal of Public Participation in Health Care and Health Policy, Sep 1, 2010
Objective To use semi-structured interviews to ascertain patterns in patientsÕ expectations of he... more Objective To use semi-structured interviews to ascertain patterns in patientsÕ expectations of health care and the extent to which these expectations were met or not.
Food Chemistry, 1990
Cocosin, an 11S seed storage globulin flora coconut, has been purified and characterised by HPLC ... more Cocosin, an 11S seed storage globulin flora coconut, has been purified and characterised by HPLC gel filtration and anion-exchange chromatography. At least eight different subunit species have been identified. Despite this heterogeneity, cocosin crystallises very readily into forms typical of this class of protein. The molecular weight of the protein was in the range 250000-300 000. higher than the value of 208 000 previously ascribed. A subunit molecular weight of approximately 54000, together with the crystal symmetry, suggests that cocosin is a typical hexameric l l S globulin, and not a tetramer as was previously postulated.
Smoking cessation and vegetable consumption : reducing cancer through communication?
Biochemical Journal
1. Protein disulphide-isomerase from bovine liver was purified to homogeneity as judged by sodium... more 1. Protein disulphide-isomerase from bovine liver was purified to homogeneity as judged by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, twodimensional electrophoresis and N-terminal amino acid analysis. The preparative procedure, a modification of that of Carmichael, J. Biol. Chem. 252, 7163-71671, is much faster and higher-yielding than previous procedures, and the final purified material is of higher specific activity. 2. The enzyme has Mr 57000 as determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, both in the presence and in the absence of thiol compounds. Gel-filtration studies on Sephadex G-200 indicate an M, of 107000, suggesting that the native enzyme is a homodimer with no interchain disulphide bonds. Ultracentrifugation studies give a sedimentation coefficient of 3.5S, implying that the enzyme sediments as the monomer. 3. The isoelectric point, in the presence of 8 M-urea, is 4.2, and some microheterogeneity is detectable. 4. The amino acid composition is comparable with previous analyses of this enzyme from bovine liver and of other preparations of thiol: protein disulphide oxidoreductases whose relation to protein disulphide-isomerase has been controversial. The enzyme contains a very high proportion of Glx + Asx residues (27%). The N-terminal residue is His. 5. The pure enzyme has a very small carbohydrate content, determined as 0.5-1.0% by the phenol/H2SO4 assay. Unless specific steps are taken to remove it, the purified enzyme contains a small amount (5 mol/mol of enzyme) of Triton X-100 carried through the purification.
Poor diet and smoking : the big killers : comparing health education in two hazard domains
British Food Journal
Encouraging the UK public to quit smoking has been a public health feature for over a century to ... more Encouraging the UK public to quit smoking has been a public health feature for over a century to a greater or lesser degree. Persuading people to consume five or more portions of fruits and vegetables is a far newer health policy, with a history of only some ten years. The article compares the established anti-smoking campaign with that of the
The latency of rat liver microsomal protein disulfide-isomerase
Biochemical Journal
ABSTRACT
Protocol for purification of pea storage proteins and characterization of their aggregation state
Biochemical Society Transactions, 1986
The dissociation of pea 11S storage protein by salt, as measured by light scattering
Biochemical Society Transactions, 1987
Effect of ethoxyquin on glutathione levels and peroxidisability of rat liver membranes
Biochemical Society transactions, 1996
... of rat liver membranes. GEOFFREY W. PLUMB, NIGEL LAMBERT, STEPHEN J.CHAMBERS, HELEN L. CLARKE... more ... of rat liver membranes. GEOFFREY W. PLUMB, NIGEL LAMBERT, STEPHEN J.CHAMBERS, HELEN L. CLARKE, MARGARET M. MANSON, GORDON NEAL and GARY WILLIAMSON. Department of Food Molecular Biochemistry ...
Influence of phenolics on protein binding to the antioxidant responsive element (ARE)
Biochemical Society transactions, 1996
Purification of a cytosolic enzyme from human liver with phospholipid hydroperoxide glutathione peroxidase activity
The International journal of biochemistry
Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is a selenoprotein which inhibits perox... more Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is a selenoprotein which inhibits peroxidation of microsomes. The human enzyme, which may play an important role in protecting the cell from oxidative damage, has not been purified or characterized. PHGPx was isolated from human liver using ammonium sulphate fractionation, affinity chromatography on bromosulphophthalein-glutathione-agarose, gel filtration on Sephadex G-50, anion exchange chromatography on Mono Q resin and high resolution gel filtration on Superdex 75. The protein was purified about 112,000-fold, and 12 micrograms was obtained from 140 g of human liver with a 9% yield. PHGPx was active on hydrogen peroxide, cumene hydroperoxide, linoleic acid hydroperoxide and phosphatidylcholine hydroperoxide. The molecular weight, as estimated from non-denaturing gel filtration, was 16,100. The turnover number (37 degrees C, pH 7.6) on (beta-(13-hydroperoxy-cis-9, trans-11-octadecadienoyl)-gamma-palmitoyl)-L-alpha-phosphatid...
Evaluation of the antioxidant properties of food extracts
Biochemical Society transactions, 1995
The Biochemical journal, 1983
Protein disulphide-isomerase was purified to homogeneity from rat liver by a rapid high-yielding ... more Protein disulphide-isomerase was purified to homogeneity from rat liver by a rapid high-yielding procedure. Structural properties of the pure enzyme were very similar to those of the bovine liver enzyme purified by the same method. The purified rat liver enzyme was subjected to two-dimensional gel electrophoresis in the presence and in the absence of microsomal membranes, and shown to co-electrophorese with a major acidic polypeptide clearly identifiable in the two-dimensional electrophoretic profile of microsomal membranes. This identification was confirmed by peptide 'mapping' of the pure enzyme and of the defined spot from a two-dimensional electrophoresis gel.
The Biochemical journal, 1983
The protein disulphide-bond isomerization activity of highly active homogeneous protein disulphid... more The protein disulphide-bond isomerization activity of highly active homogeneous protein disulphide-isomerase (measured by re-activation of 'scrambled' ribonuclease) is enhanced by EDTA and by phosphate buffers. As shown for previous less-active preparations, the enzyme has a narrow pH optimum around pH 7.8 and requires the presence of either a dithiol or a thiol. The dithiol dithiothreitol is effective at concentrations 100-fold lower than the monothiols reduced glutathione and cysteamine. The enzyme follows Michaelis-Menten kinetics with respect to these substrates; Km values are 4,620 and 380 microM respectively. The enzyme shows apparent inhibition by high concentrations of thiol or dithiol compounds (greater than 10 X Km), but the effect is mainly on the extent of reaction, not the initial rate. This is interpreted as indicating the formation of significant amounts of reduced ribonuclease in these more reducing conditions. The purified enzyme will also catalyse net reduc...