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N Wood

Publications and source records attributed to N Wood.

At least 19 recordsLinked to original sources
PubMed1995

Optimisation and properties of a UHG for genotyping of hemoglobins S and C.

The use of universal heteroduplex generators (UHG) as an effective means of screening for specific mutations has been previously reported. Here, we report the optimisation of a UHG system used for the rapid and simple detection of sickle cell hemoglobinopathies, HbS and HbC. The test involves heteroduplex formation between between polymerase chain reaction (PCR)-amplified beta-globin gene first exon sequences, and a UHG. The UHG is a synthetic DNA molecule homologous to HbA but which contains a small deletion adjacent to the HbS and HbC mutation sites in codons 5 and 6. Heteroduplexes are resolved on nondenaturing polyacrylamide minigels and are diagnostic of HbS and HbC in homozygous and heterozygous individuals. A blind trial of UHG genotyping involving eleven previously sequenced DNAs showed complete concordance between methods. In addition, we identified a characteristic heteroduplex banding pattern for the H2H silent mutation (CAC-->CAT) in codon 2.

Anemia, Sickle Cell↗
PubMed1995

The cocktail party phenomenon revisited: how frequent are attention shifts to one's name in an irrelevant auditory channel?

N. Moray's (1959) well-known study of the "cocktail party phenomenon" suggested that participants sometimes notice their name embedded in an ignored auditory channel. However, the empirical finding was preliminary in nature and never has been directly replicated. This was done with improved methodological controls, and the relationship between on-line attention shifts to one's name and subsequent recollection of the name in a sample of 34 undergraduates was examined. Similar to N. Moray, only 34.6% of the participants recalled hearing their name in the channel to be ignored. Only those participants showed on-line evidence of attention shifts, and those shifts occurred only for the two items following the name. The results suggest that participants who detected their name monitored the irrelevant channel for a short time afterward.

Affect↗
PubMed1995

Rapid genotype analysis in type 2B von Willebrand's disease using a universal heteroduplex generator.

A new diagnostic technique based on DNA heteroduplex analysis has been used to identify specific point mutations in the von Willebrand's factor (vWF) gene of patients with von Willebrand's disease type 2B. Molecular analysis in these patients has shown previously that their mutations are clustered in a short region of sequence in exon 28 of the vWF gene. The principle of the method involves heteroduplex formation between amplified genomic sequence containing the defect and an exon 28 vWF gene universal heteroduplex generator (UHG). The UHG is a synthetic vWF gene exon 28 homologue which contains a number of sequence mismatches designed to generate allele specific heteroduplexes for each type 2B mutation. Individual mutant genotypes are identified by characteristic banding patterns following polyacrylamide minigel electrophoresis. The technique is rapid, simple, inexpensive, and is ideally suited for adoption by non-specialist haematology laboratories for screening purposes.

Base Sequence↗
PubMed1994

A review of primary health-care organization.

A contract for the provision of community nursing and associated services was drawn up between the Plymouth Community Unit and general practitioners associated with a fundholding practice at a health centre in Devon in October 1991. This project, which aimed at applying purchaser/provider principles, contained some novel features and was subject to evaluation and review after 6 months. An evaluation which had four main aspects was carried out, consisting of interviews and questionnaire assessment of staff attitudes, patients' views of the effectiveness of aspects of the practice health-promotion activity, an analysis of staff activity data before and during the pilot phase and an examination of the documentation concerned with critical issues which had arisen. Questionnaire data indicated that staff motivation and enthusiasm for the project was high and that patients' views on the practice facilities were generally positive. The role of the Macmillan nursing service at this practice was greatly enhanced during the pilot project with a fourfold increase in the number of visits carried out. Over 120 h were spent by health visiting and district nursing staff on issues surrounding the pilot project including attending additional meetings. The results are discussed in relation to service benefits to patients, the effect on the cohesion of the primary health-care team and issues of fundholding and are considered in the context of models put forward for the future development of community-based nursing care.

Adult↗
PubMed1994

Multiple sclerosis.

Differences in the risk of multiple sclerosis depending on racial background, and the high clinical concordance rates in monozygotic compared with dizygotic twins, have stimulated attempts to identify and locate genes that confer susceptibility to the disease. The risk of multiple sclerosis is increased from 1 in 800 in northern European Caucasians to 1 in 3 in the monozygotic co-twins of affected individuals, with intermediate rates for siblings, offspring and more distant relatives. Concordance rates in monozygotic and dizygotic co-twins of affected individuals rise to 35% and 15%, respectively when magnetic resonance imaging is used to supplement clinical evidence for disease status. The increased recurrence risk in relatives of patients with multiple sclerosis is consistent with a model in which more than one gene contributes to susceptibility. Population studies have demonstrated an association with the class 2 major histocompatibility complex (MHC) phenotypes DR15 and DQw6 and their corresponding genotypes DRB1.1501, DRB5.0101 and DQA1.0102, DQB2.0602. An extensive search, using population studies, for other polymorphic alleles involved in restriction of the immune response may have yielded an additional candidate gene in the VH2-5 immunoglobulin heavy-chain variable region. Identity by descent analysis of candidate genes encoded within the alpha-chain of the T-cell receptor and the gene for myelin basic protein has failed to demonstrate linkage; paradoxically, this is also true for the MHC class 2 region, despite the population association. However, studies involving a large number of sibling pairs have reported a bias in the distribution of T-cell receptor beta-chain variable region haplotype sharing, favouring linkage. This becomes more marked when stratification is made for the presence of DR2 in both affected siblings, suggesting an interaction between genetic polymorphisms encoded within the MHC and T-cell receptor genes, as expected from their known functional co-operation in antigen presentation. The same is true for the immunoglobulin heavy chain, providing provisional evidence for linkage to a gene encoded within the immunoglobulin heavy-chain variable region in families reported from the UK. Taken together, these findings demonstrate the importance of family studies in elucidating the genetic basis of multiple sclerosis, and confirm that several genes are involved, one or more of which regulates genetic restriction of the immune response. The contribution made by the susceptibility genes that have provisionally been identified, occurring in isolation or together, can account for only a proportion of the increased risk of multiple sclerosis implicated by family studies.(ABSTRACT TRUNCATED AT 250 WORDS)

Genes↗
PubMed1993

Rapid classification of phenylketonuria genotypes by analysis of heteroduplexes generated by PCR-amplifiable synthetic DNA.

We describe a rapid and simple method for phenylketonuria genotyping which identifies five point mutations within exon 12 of the human phenylalanine hydroxylase gene. The method involves PCR amplification of the target exon and hybridization with a PCR-amplifiable synthetic DNA (universal heteroduplex generator, UHG). The UHG contains identifiers consisting of nucleotide substitutions and/or deletions, contiguous with known mutation sites within the target exon. DNA heteroduplexes are resolved by nondenaturing polyacrylamide minigel electrophoresis. Individual mutant genotypes are identified by characteristic banding patterns, in either homozygous or heterozygous states. The method may potentially be applied to rapid genotyping of any mutation or series of mutations within PCR-amplifiable genetic material.

Base Sequence↗
PubMed1993

Perceptions and reactions of the public to diarrhoea.

A questionnaire about diarrhoea and how people react to it was answered by 400 people aged 16-70 years, most of whom were in employment (77% of respondents). There was wide variation in perceptions and reactions. Older persons and people in skilled trades were more likely to consider any increased bowel looseness or frequency of their usual bowel habit as diarrhoea, compared to younger persons and people in professional and managerial positions. Over half the respondents rated a single soft stool as diarrhoea, and almost a third accepted likewise an increased frequency of defaecation. The most unpleasant aspect of diarrhoea was considered to be incontinence with soiling of underclothes. At the onset of diarrhoea, 16% of respondents would not wait even a day or two but would go straight to a pharmacist, and 8% would go direct to a doctor. Persons in professional and managerial positions were less likely to attend their doctor straight away than people in other occupational groups. The findings show that for improved clinical management and public health surveillance, health professionals should not accept the term when it is used by patients, but seek details of their defaecation patterns and the form of their stools. Improved public education is needed as to self-help, appropriate treatment and when to seek pharmaceutical and medical advice.

Adolescent↗
PubMed1993

Cholesteryl ester transfer protein and high density lipoprotein responses to cholesterol feeding in men: relationship to apolipoprotein E genotype.

The apolipoprotein (apo) E isoform is an important determinant of the plasma lipoprotein distribution of apoE and of the metabolism of apoE-containing lipoproteins. We have determined the effects of apoE genotype on the plasma lipoprotein response to cholesterol feeding in 30 young normal male subjects (5 E3/2, 11 E3/3, 14 E4/3) under rigorously controlled dietary conditions. Two diets, differing only in cholesterol content (low cholesterol (LC): 80 mg cholesterol/1000 kcal and high cholesterol (HC): 320 mg cholesterol/1000 kcal), were compared using a random crossover design. At the end of the HC as compared to the LC period, total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), and HDL2-C increased by an average of 15%, 21%, 7%, and 23%, respectively, for the three genotype groups combined (P < 0.001 for each). The LDL-C response to dietary cholesterol did not differ among the apoE genotypes. However, the increase in HDL-C varied significantly according to the apoE genotype (E3/2: 0 change, E3/3: +4%, E4/3: +12%; P < 0.05). The plasma cholesteryl ester transfer protein (CETP) response to cholesterol feeding also differed amongst the three apoE genotype groups (E3/2: +37%, E3/3: +18%, E4/3: +9%) (P < 0.05). ApoE genotype has significant and opposite effects on plasma CETP and HDL-C responses to dietary cholesterol in men.

Adipose Tissue↗
PubMed1992

Differences in neurokinin receptor pharmacology between rat and guinea-pig superior cervical ganglia.

1. The depolarizations elicited by seven neurokinin receptor agonists were examined in both rat and guinea-pig superior cervical ganglia by use of grease-gap methodology in the presence of tetrodotoxin (0.1 microM). Responses were normalised with respect to 1 microM eledoisin. 2. The rank order of agonist potency in the rat ganglia was senktide greater than substance P greater than substance P methyl ester = eleidosin = Sar-Met-substance P greater than neurokinin B greater than neurokinin A, whereas in guinea-pig superior cervical ganglion (SCG) the rank order was senktide greater than Sar-Met-substance P greater than neurokinin B = eledoisin = substance P methyl ester. The concentration-effect curves for substance P and neurokinin A in guinea-pig ganglia were biphasic which precluded the determination of meaningful potency values. 3. The maximal depolarization achieved by subtype selective ligands was different between these two species. On rat and guinea-pig SCG, the NK3-selective ligand, senktide, produced a maximal depolarization of 27% and 274% respectively, whereas the NK1-selective ligand, substance P methyl ester, produced depolarizations of 77% and 64% respectively. 4. The depolarizations induced by substance P methyl ester and senktide in either species were unaffected by atropine (1 microM), suggesting a lack of involvement of presynaptic neurokinin receptors in the generation of the response. 5. The potency of substance P methyl ester, senktide, and neurokinin A were unaffected by pretreating ganglia with the peptidase inhibitors bacitracin (40 micrograms ml-1), leupeptin (4 micrograms ml-1), and chymostatin (2 micrograms ml-1). Similarly, these peptidase inhibitors had no effect on the maximal depolarizations achieved by any of these agonists.6. It is evident that rat and guinea-pig superior cervical ganglia possess both NK, and NK3 receptors, but that their net contribution to depolarizations are different between the two species. The depolarizations in guinea-pig SCG are mediated predominantly by an NK3 subtype and in rat SCG by an NK, receptor subtype.

Animals↗
PubMed1992

Nucleotide sequencing of HLA-DQ gene second exons in Chinese homozygous cells.

Six HLA class I and class II-homozygous Chinese cell lines with unique HLA-Dw types were studied. Since the majority of HLA class II nucleotide sequence polymorphism is localized within the second exons of the genes, we used the polymerase chain reaction (PCR) to amplify these regions in HLA-DQA and DQB genes and subsequently determined the nucleotide sequences. No unique DQA1 or DQB1 alleles were found. However, a new haplotype of DQA1*0601-DQB1*0301-DRB1*1202 was found in two cells; and DQA1*03011 was found in association with DR9 in another two cells. This indicates that new DR-DQ associations may explain the observed new HLA-Dw types. The DQB2 sequences were identical in all six cells and were identical to a sequence previously reported in a DR6 haplotype. The DQA2 sequences from two clones obtained from two cells differed from each other and from previously reported sequences. The results show that the DQA1 and DQB1 alleles in the Chinese individuals studied are as previously reported in Caucasian populations and as such may be typed by restriction fragment-length polymorphism (RFLP) or PCR-sequence-specific oligonucleotide typing (PCR-SSO) or PCR-RFLP using conventional probe or restriction enzyme sets.

Base Sequence↗
PubMed1992

Which way for housing and human settlements?

In order to clarify the housing and settlements component of the European health-for-all programme and to identify perceived priorities with a view to the preparation of training materials, members of WHO's Rural and Urban Development and Housing Network were invited to complete a questionnaire. The results are reported below. The questionnaire can be used in identifying local development priorities, comparing attitudes, and studying perceived needs. Intended as a tool for policy-makers, course organizers and public health professionals, it is available from the authors of the present article.

City Planning↗
PubMed1991

Identifying research interests within the association of schools of public health in the European region: a pilot study.

A questionnaire survey of individuals working within schools of public health in Europe was carried out in order to identify research interests, the use of computer facilities and research collaborations being conducted. One hundred and sixteen replies were received. Just under one quarter of respondents had conducted research into health care systems or policy within the past five years and about 10% had conducted research into new educational methodologies and their evaluation. A total of 371 research collaborations were identified. The results are discussed in relation to the methodology employed and the objectives of the World Federation for Education and Research in Public Health.

Academies and Institutes↗
PubMed1991

Elevation of a gamma delta T cell subset in peripheral blood and synovial fluid of patients with rheumatoid arthritis.

We examined the levels of TcR delta 1+ T cells (total gamma delta T cell) and delta TCS1+ (gamma delta T cell subset) T cells in the peripheral blood (PB) and synovial fluid (SF) of 16 patients with rheumatoid arthritis (RA) and compared them to the levels in PB of patients with Felty's syndrome (FS) and 21 healthy control subjects (NML). Synovial fluid from eight patients with seronegative spondyloarthropathies (SSA) was also examined. The results demonstrated elevated levels of the delta TCS1+ subset in the PB of RA and FS patients relative to NML (P less than 0.05). No such differences were observed in the levels of PB TcR delta 1+ T cells. The results did not appear to reflect a non-specific inflammatory response since delta TCS1 T cells were elevated in the SF of RA patients relative to SSA SF and NML PB. delta TCS1 T cells in SSA PB and SSA SF were comparable to NML PB. TcR delta 1+ T cells levels in RA SF were higher than SSA SF levels but were comparable to those of NML PB. Taken together, the results support a pathogenic role for delta TCS1+ T cells in RA.

Antibodies, Monoclonal↗