Search PubMed⌕ Search

Biomedical subjects

D Nash

Publications and source records attributed to D Nash.

At least 37 records · Page 2Linked to original sources
PubMed1998

Coping and parental history of cardiovascular disorders influence blood pressure in women tested during different phases of their menstrual cycles.

An anger-provocation paradigm was used to assess coping and stress reactivity in 20 women with a positive parental history of cardiovascular disorders and 14 women whose parents had no cardiovascular disease. Frequency of seeking social support in the natural environment was assessed, as were systolic and diastolic blood pressures, while the women performed anger-inducing arithmetic and speech-stressor tasks during the premenstrual and postmenstrual phases. Premenstrually, the women with a positive cardiac history sought support less frequently than those with a negative history. No differences were found between the groups postmenstrually. When the women were identified according to the frequency with which they sought social support, those who more often sought support registered lower baseline blood pressure levels than those women who less often sought support during both cycle phases. Extending the stress-buffering effects of social support to include efforts at seeking support is discussed.

Adaptation, Psychological↗
PubMed1998

Health surveillance using an occupational medical database.

This pilot study sought associations between liver function tests (LFTs) and membership in homogeneous exposure groups (HEGs) at a target plant as pre-clinical indications of possible future occupational health problems. A large company database yielded linear models for each of six LFTs (total bilirubin, alkaline phosphatase, gammaglutamyl transferase, lactate dehydrogenase, aspartate transaminase, and alanine transaminase) in terms of sex, body mass index, age, race (white/non-white), alcohol and cigarette consumption, and production/non-production (P/NP) job, permitting control for these in analyses of LFTs vs HEGs at the plant. These analyses, with HEG substituted for P/NP in the large group model, resulted in loosely "suspect" associations significant at P < 0.10. Collapsed HEG variable (containing "suspects" separately and all other non-significant HEG levels pooled) yielded "confirmed suspects" at P < 0.05 in the analysis of an independent LFT set taken at the plant approximately one year later.

Data Interpretation, Statistical↗
PubMed1998

The role of pharmacoeconomic evaluations in disease management.

Disease management is a systematic approach to a health condition or a healthcare intervention that organises preventative, interventional and care approaches throughout the continuum of care and which measures outcomes in terms of populations, not individuals. Disease management's advantage over the current component system is that it stresses prevention over acute treatment of a chronic disease. Patients with better control of their chronic diseases will likely have a decrease in the use of emergency room and inpatient hospitalisation services, thereby improving clinical outcomes of patients. To achieve these goals, disease management uses pharmacoeconomic evaluations and outcomes measures to provide information that helps build formularies and clinical practice guidelines. Several problems exist in integrating pharmacoeconomic studies in disease management models, such as the need for more integrated information systems, standardisation and who should perform these evaluations. Some possible solutions will be addressed in this article. With greater emphasis being placed on controlling costs, the need for pharmacoeconomic evaluations in the design of disease management models will continue to increase in the future.

Cost Control↗
PubMed1997

An epidemic of lung cancer due to chloromethyl ethers. 30 years of observation.

A cohort of 125 chemical workers was established in 1963 to investigate an epidemic of lung cancer caused by industrial exposure to chloromethyl ethers (CME). Ninety-three of the men were exposed to CME, and approximate estimates of exposure were made. Standardized mortality ratios (SMRs) were calculated for lung cancer, based on Philadelphia city rates. Over 30 years of observation, 25 of 67 deaths were due to lung cancer, with a dose-response relationship. SMRs were elevated only among 59 moderately and heavily exposed workers, peaked at 23.1 in the first decade, and then declined to 7.4 and 7.9 in later decades. The mean latency period from onset of exposure to death was 21 to 25 years and was inversely related to cumulative exposure. Three of 12 heavily exposed cases occurred in nonsmokers. Small cell carcinoma accounted for 80% of the moderately and heavily exposed cases.

Adult↗
PubMed1996

Hydrogen-exchange kinetics in the cold denatured state of ribonuclease A.

Ribonuclease A (RNase A) exhibits a well-defined cold denaturation transition when examined at high pressure (3 kbar) and low temperatures (below -10 degrees C). Our main interest in this study was to investigate the pressure-assisted cold denatured state of RNase A by hydrogen exchange techniques. The protection factors obtained from the kinetic data are similar to those obtained previously for RNase A denatured by exposure to high pressure near its temperature of maximum stability, but differ markedly from those in thermally denatured RNase A. A qualitative analysis of the hydrogen-exchange rates suggests that cold denatured RNase A behaves markedly differently from a random coil, probably due to patches of residual secondary structure.

Amides↗
PubMed1996

Cross-screening: a new method to assemble clones rapidly and unambiguously into contigs.

We have developed a new procedure that relies on an array of cross-hybridization tests to order a set of random clones into a contig. The method, called cross-screening, uses each clone as a target and its end sequences as probes, in a matrix of reciprocal cross-hybridization tests performed on a single blot. The relationships among the clones are determined rapidly from the pairwise tests, allowing clone order to be determined directly. We have applied this technique to DNAs from a set of overlapping lambda clones from Drosophila chromosome 4. The location and orientation of each clone derived from the cross-screening data was that expected from the map assembled from overlapping restriction sites and chromosomal walking. The procedure provided additional information on a previously unknown, internally repeated DNA sequence. To demonstrate the general utility of the procedure, we have applied it to a previously described clone set within a contig in region 22q12 of human chromosome 22. The correct relative position and orientation of these clones were derived from the cross-screening data without knowledge of, or reference to, any nucleotide sequence or restriction site analysis of the DNA concerned. The cross-screening procedure is fast, economical, and robust and allows clone overlaps to be determined efficiently, with minimal interference from repeated DNA sequences. This new procedure is specifically designed for small groups of overlapping clones (tens to hundreds) and should facilitate the ordering of subclone libraries derived from small chromosomes or the large cloned inserts carried in YAC, BAC, and P1 vectors.

Animals↗
PubMed1995

Dorsal wing, a locus that affects dorsoventral wing patterning in Drosophila.

The wing imaginal disc is subdivided into a dorsal and a ventral compartments. A new dominant homeotic mutation, Dorsal wing1 (Dlw1), transforms ventral into dorsal compartment in heterozygotes. This phenotype is similar to one of the dominant phenotypes of Polycomb (Pc) mutants. In Pc Dlw+/Pc+ Dlw1 double mutants, the transformation is greatly enhanced. The recessive phenotype of Dlw1 is the opposite to the dominant phenotype. Dlw1/Dlw1 somatic clones induced at any larval stage differentiate only ventral pattern on both wing surfaces. This effect is one of the somatic clone phenotypes of trithorax (trx) lethals. A similar dorsal-to-ventral transformation is observed in Pc Dlw/Dlw clones. Dlw1/Dlw1 clones have no effect elsewhere, except in the dorsal notum, which may differentiate extra macrochaetes. We propose that: (1) Dlw+ is required for the specification of dorsal compartment; (2) some genes of the Polycomb group act as negative regulators of Dlw+, while some genes of the trithorax group act as positive regulators.

Animals↗
PubMed1994

Two solutions to the problem of noise exposure for motorcyclists.

Two solutions to the problem of excessive noise exposure and consequent hearing loss in motorcyclists were investigated and are described. One was an antecedent behaviour-modifying 'prompting' strategy, where a set of earplugs and an advice sheet were provided at the point of sale to consecutive purchasers of new motorcycle crash helmets. Forty-eight riders were recruited but data for analysis were only available in 41. The earplug usage rate was significantly increased from 27% to 83% by this intervention. The second solution involves various aerodynamics and sound-proofing helmet modifications made in an effort to reduce interior noise levels. The only modification which achieved a significant reduction from previously reported average sound levels was the incorporation of a pair of 'standard' earmuffs under the helmet shell. This gave noise levels of 84 dB(A) at 22 m/s (50 mph) and 93 dB(A) at 36 m/s (80 mph), compared to known average values of 95 dB(A) and 107 dB(A), respectively. Both solutions are eminently feasible and desirable, and we hope that the motorcycle industry will act on them.

Adult↗
PubMed1994

The raspberry locus of Drosophila melanogaster includes an inosine monophosphate dehydrogenase like coding sequence.

DNA from the raspberry gene of Drosophila melanogaster has been cloned through P-element tagging of a dysgenically induced lethal allele. A transcribed DNA segment adjacent to the P insert encodes an amino acid sequence that is similar to known inosine monophosphate dehydrogenase (IMPDH) sequences. Further dysgenically induced lethals and all four known spontaneous ras eye-colour mutations have changes in the DNA either within or just upstream from the transcribed region. Identification of IMPDH as a probable product of the ras gene is compatible with the finding of an allele that requires dietary guanosine (GR), since the enzyme mediates the first of two biosynthetic steps leading from inosine monophosphate (IMP) to guanosine monophosphate (GMP). However, other auxotrophic mutants at the locus remain unexplained by the finding. The results further suggest that GMP synthesis from IMP is an essential process, despite the capacity of the fly for salvage synthesis of GMP from GR. Consideration of the phenotypes associated with mutants at the ras locus suggests that IMPDH activity is regulated in a tissue-specific manner.

Alleles↗