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Biomedical subjects

J Gunn

Publications and source records attributed to J Gunn.

At least 55 records · Page 3Linked to original sources
PubMed1999

The economic impact of mastitis-control procedures used in Scottish dairy herds with high bulk-tank somatic-cell counts.

We used multiple-regression analysis of field data to quantify the marginal impacts of various mastitis-control procedures on bulk-tank somatic-cell count (BTSCC). Estimates of milk-yield depression and the probability of herds paying a BTSCC penalty due to the presence of subclinical mastitis were made. An assessment of the economic efficiency of mastitis control by high BTSCC producers was also made using a loss-expenditure frontier. Significant interactions were detected between premilking udder-preparation methods (UP) and post-milking teat disinfection (PMTD), and also between the milking system of the herds and both the use of dry-cow therapy (DCT) and a regular milking-machine test (MMT). Udder preparation involving washing was associated with a higher SCC and had a detrimental effect on the efficacy of PMTD. Amongst herds facing a high-BTSCC problem (BTSCC >400,000 cells/ml), herds using PMTD without UP (regardless of the type of milking system), those using DCT (in parlour systems), and those with a parlour system having their milking machines tested obtained returns of Pound Sterling 1.4, Pound Sterling 3.9 and Pound Sterling 1.1, respectively, per Pound Sterling 1 investment in each of these procedures as a result of reductions in milk-yield losses and BTSCC penalties. The minimum total cost of disease within these herds was Pound Sterling 65.50/cow/year (due to Pound Sterling 41.40 revenue losses plus Pound Sterling 24.10 mastitis-control expenditure) attained by herds which had a parlour system and used DCT, MMT and PMTD (without UP). However, the average cost of subclinical mastitis for all high-BTSCC farms was Pound Sterling 100/cow/yr; hence, the difference (pound Sterling 34.50) could be saved by the more-efficient application of mastitis-control procedures.

Animal Husbandry↗
PubMed1999

Interleukin-1 receptor antagonist gene polymorphism and coronary artery disease.

BACKGROUND: Cytokine gene variations are contributory factors in inflammatory pathology. Allele frequencies of interleukin (IL)-1 cluster genes [IL-1A(-889), IL-1B(-511), IL-1B(+3953), IL-1RN Intron 2 VNTR] and tissue necrosis factor (TNF)-alpha gene [TNFA(-308)] were measured in healthy blood donors (healthy control subjects), patients with angiographically normal coronary arteries (patient control subjects), single-vessel coronary disease (SVD), and those with multivessel coronary disease (MVD). METHODS AND RESULTS: Five hundred fifty-six patients attending for coronary angiography in Sheffield were studied: 130 patient control subjects, 98 SVD, and 328 MVD. Significant associations were tested in an independent population (London) of 350: 57 SVD, 191 MVD, and 102 control subjects. IL-1RN*2 frequency in Sheffield patient control subjects was the same as in 827 healthy control subjects. IL-1RN*2 was significantly overrepresented in Sheffield SVD patients (34% vs 23% in patient control subjects); IL-1RN*2 homozygotes in the SVD population (chi2 carriage=8.490, 1 df, P=0.0036). This effect was present though not quite significant in the London population (P=0. 0603). A summary trend test of the IL-1RN SVD genotype data for Sheffield and London showed a significant association with *2 (P=0. 0024). No significant effect of genotype at IL-1RN was observed in the Sheffield or London MVD populations. Genotype distribution analysis comparing the SVD and MVD populations at IL-1RN showed a highly significant trend (P=0.0007) with the use of pooled data. No significant associations were seen for the other polymorphisms. CONCLUSIONS: IL-1RN*2 was significantly associated with SVD. A difference in genetic association between SVD and MVD was also apparent.

Coronary Disease↗
PubMed1999

Ashworth revisited

Explore the source record for details and available documents.

Journal Article↗
PubMed1999

Do routinely measured delivery variables predict anal sphincter outcome?

PURPOSE: Trauma to the anal sphincter is a recognized complication of primiparous childbirth. This damage may be compounded during subsequent deliveries leading to symptoms. Earlier work is inconclusive as to which delivery variables are associated with such damage and may prove useful in predicting its occurrence, thereby allowing the potential for intervention in these later deliveries to protect the traumatized anal sphincter. The purpose of the present study was to determine whether routinely recorded obstetric variables can be correlated to anal sphincter damage in a consecutive series of females. METHODS: A prospective study was undertaken in a single maternity unit. Patients delivering were assessed before discharge using a symptom questionnaire and endoanal ultrasound. Delivery data were collected prospectively and analyzed statistically to see if a significant difference existed in the presence of an anal sphincter defect. RESULTS: A total of 159 patients were assessed. Endosonography revealed sphincter injuries in 8.7 percent of the normal vaginal delivery group and 83 percent of the forceps delivery group. No correlation was found between head circumference, baby weight, maternal body mass index, epidurals, episiotomy, length of each stage of labor, and duration of active pushing. Forceps delivery was the only factor to be significantly associated with sphincter trauma. CONCLUSION: Besides forceps delivery, commonly measured delivery variables are not useful predictors of anal sphincter trauma. Normal vaginal deliveries do not warrant routine postnatal anorectal assessment, but this should be routine for all instrument deliveries.

Adult↗
PubMed1999

Obstetric anal sphincter injury: prospective evaluation of incidence.

PURPOSE: An obstetrically damaged anal sphincter is the principal cause of the development of fecal incontinence in otherwise healthy females. Reports suggest that such damage complicates as many as 35 percent of primiparous vaginal deliveries, with 13 percent of first-time mothers becoming symptomatic. In maternity units delivering 3,000 patients annually, it would follow that 390 symptomatic patients would develop new symptoms each year. This incidence of dysfunction does not reflect current clinical practice. We have investigated this discrepancy to establish the actual incidence of anal sphincter trauma associated with childbirth. METHODS: During a six-week period, 159 females (105 primiparous and 54 para-I) were prospectively assessed postnatally using a standardized symptom questionnaire, endoanal ultrasound, and anal manometry. This group constituted 84 percent of all eligible deliveries occurring in the unit during the study period. RESULTS: One patient developed fecal urgency after this delivery; there were no reports of fecal incontinence. Anal sphincter injuries were identified ultrasonically in 6.8 percent of primiparous patients, 12.2 percent of para-I patients having vaginal deliveries, and 83 percent of patients having forceps deliveries overall. Manometric data provided confirmatory evidence, with significantly reduced maximum squeeze pressures in patients with a disrupted anal sphincter (P<0.0005). CONCLUSIONS: A symptom questionnaire is inadequate to identify anal sphincter injuries. The incidence of sphincter injury in relation to vaginal delivery has been overestimated in previous published work. This study demonstrates that the true incidence is 8.7 percent overall and that symptoms of sphincter dysfunction are uncommon this is in keeping with current clinical practice.

Adolescent↗
PubMed1999

Temporal and spatial distribution of interleukin-1 beta in balloon injured porcine coronary arteries.

OBJECTIVE: Interleukin-1 beta (IL-1 beta) is a proinflammatory cytokine with a wide range of biological activities. We determined the distribution of IL-1 beta following percutaneous transluminal coronary angioplasty (PTCA) of porcine arteries, and the presence of caspase-1 (required for the activation of IL-1 beta). METHODS: Oversized balloon angioplasty was performed in Yorkshire White pigs and the vessels excised at selected intervals (1, 6, 18 h, 3, 7, and 14 days) post-PTCA. IL-1 beta and caspase-1 were then identified using reverse transcription polymerase chain reaction (RT-PCR), in situ RT-PCR, and immunohistochemistry. RESULTS: IL-1 beta protein was detected in the inflammatory infiltrate up to 3 days after PTCA. Luminal endothelial cells contained IL-1 beta at 1 h, with peak expression at 3-7 days. Adventitial capillaries were IL-1 beta-positive at all timepoints. IL-1 beta was detected in adventitial cells at 3 days, with reduced levels at 7 and 14 days. At 7 days, neointimal cells were also IL-1 beta positive. No IL-1 beta was detected in non-PTCA control arteries. RT-PCR demonstrated IL-1 beta mRNA expression to be induced at 1 h, and absent at 3 days. In situ RT-PCR revealed this expression to be distributed throughout the arterial layers at 6 h, but localized to the adventitia at 18 h, with a baseline expression in the adventitial layer of non-PTCA controls. Caspase-1 was detected in luminal endothelial cells from 6 h, in adventitial cells from 3 days, and in neointimal cells from 7 days post-PTCA. This expression colocalized with IL-1 beta, indicating the potential for the IL-1 beta present to become activated. CONCLUSIONS: We conclude that IL-1 beta is synthesised, in conjunction with caspase-1, by endothelial, inflammatory, and adventitial cells early (within 3 days) after PTCA, with decreased levels at later timepoints, suggesting that it has a key role to play in the early stages of healing following PTCA.

Angioplasty, Balloon, Coronary↗
PubMed1999

Analysis of potential markers for detection of submicroscopic lymph node metastases in breast cancer.

We have developed sensitive assays for cytokeratin (K) 8, 16, 19, stromelysin 3 (ST3), MUC1 and maspin mRNAs using reverse transcription polymerase chain reaction (RT-PCR) and used these to assess lymph node status in patients undergoing surgery for breast cancer. In addition the RT-PCR assays were tested against lymph nodes from non-cancer patients to determine their specificity. Despite high sensitivity RT-PCR assays for K8, K16, K19, ST3 and maspin were not found to be useful as markers of submicroscopic disease as transcripts of these genes were detected in the great majority of control lymph nodes tested. Expression of MUC1 was also not found to be useful as it was both insensitive and non-specific. The importance of assessing potential markers against an adequately sized control population is demonstrated, as failure to do so can lead to erroneous conclusions.

Biomarkers, Tumor↗
PubMed1999

Primer postcard improves postal survey response rates.

OBJECTIVE: This study measures the effect of an intervention to improve mailed survey response rates. METHOD: A randomised controlled trial of a 'primer' postcard was performed as part of a large survey in Victoria in 1997. Prior to the survey mailout, half the sample of 800 general practitioners supplied by the Health Insurance Commission was sent, at random, a primer card to request prompt return of the survey. RESULTS: The intervention resulted in a more rapid return of the survey and improved overall response rates from 60% to 66%. The increased cost per returned survey (40 cents) was largely offset by fewer non-responders requiring follow-up. CONCLUSIONS: A primer postcard is a time and cost-efficient method to increase response rates in general practitioner surveys. IMPLICATIONS: Public health researchers should consider implementing this intervention to improve response rates to postal surveys. Reports of other response maximising strategies should report the cost per returned survey to allow better comparison.

Attitude of Health Personnel↗
PubMed1999

Homicides by people with mental illness: myth and reality.

BACKGROUND: Tragic and high profile killings by people with mental illness have been used to suggest that the community care model for mental health services has failed. AIMS: To consider whether such homicides have become more frequent as psychiatric services have changed. METHOD: Data were extracted from Home Office-generated criminal statistics for England and Wales between 1957 and 1995 and subjected to trends analysis. RESULTS: There was little fluctuation in numbers of people with a mental illness committing criminal homicide over the 38 years studied, and a 3% annual decline in their contribution to the official statistics. CONCLUSIONS: There are many reasons for improving the resources and quality of care for people with a mental disorder, but there is no evidence that it is anything but stigmatising to claim that their living in the community is a dangerous experiment that should be reversed. There appears to be some case for specially focused improvement of services for people with a personality disorder and/or substance misuse.

Attitude to Health↗
PubMed1999

Outcome of admission to a medium secure psychiatric unit. I. Short- and long-term outcome.

BACKGROUND: This is the first long-term follow-up of patients discharged from a medium secure unit. AIMS: To describe the short- and long-term outcomes of admission for all patients discharged during a 14-year period. METHOD: A longitudinal cohort study of all 234 patients discharged from the Denis Hill Unit, Bethlem Royal Hospital, between 1980 and 1994, followed for an average 6.6 years. RESULTS: Although 48% of admissions were from prison, only 8% returned there, with most being transferred to another psychiatric bed. One-fifth of patients spent none of the follow-up time in the community; 75% of patients had at least one readmission; only 24% were convicted of further offences. CONCLUSIONS: Re-offending rates are comparable with those for patients discharged from high-security hospitals, and much lower than those for released prisoners. The high readmission rates indicate the need for a range of services to maintain former patients in the community.

Adolescent↗
PubMed1999

New Developments in Therapeutic Ultrasound-Assisted Coronary Angioplasty.

Ultrasound at high energy, as distinct from the low energy used in ultrasound imaging, has found many uses in varied branches of medicine and surgery. Clinical trials of catheter-delivered, high-energy, low-frequency (kHz) ultrasound over the past 6 years have shown the safety of this modality in the treatment of coronary artery disease and have identified a number of indications in which its use, as an adjunct to conventional percutaneous transluminal coronary angioplasty (PTCA) techniques, may offer therapeutic advantages. Thrombus-mediated conditions--such as myocardial infarction, chronic total occlusion, and atherosclerosis in small vessels--appear to derive particular benefit from ultrasound treatment. Recent developments in these fields are reviewed.

Journal Article↗
PubMed1998

Apoptosis and cell proliferation after porcine coronary angioplasty.

BACKGROUND: Angioplasty initiates a number of responses in the vessel wall including cellular migration, proliferation, and matrix accumulation, all of which contribute to neointima formation and restenosis. Cellular homeostasis within a tissue depends on the balance between cell proliferation and apoptosis. METHODS AND RESULTS: Profiles of apoptosis and proliferation were therefore examined in a porcine PTCA injury model over a 28-day period. Forty-two arteries from 21 pigs, harvested at the site of maximal injury at 1, 6, and 18 hours, and 3, 7, 14, and 28 days after PTCA, were examined (n=3 animals per time point). Uninjured arteries were used as controls. Apoptosis was demonstrated by the terminal uridine nick-end labeling (TUNEL) method, transmission electron microscopy (TEM), and DNA fragmentation. Cells traversing the cell cycle were identified by immunostaining for proliferating cell nuclear antigen (PCNA). Apoptosis was not detected in control vessels at all time points nor at 28 days after PTCA. Apoptotic cells were identified at all early time points with a peak at 6 hours (5.1+/-0.26%; compared to uninjured artery, P<0.001) and confirmed by characteristic DNA ladders and TEM findings. Regional analysis showed apoptosis within the media, adventitia, and neointima peaked at 18 hours, 6 hours, and 7 days after PTCA, respectively. In comparison, PCNA staining peaked at 3 days after PTCA (7.16+/-0.29%; compared to 1.78+/-0.08% PCNA-positive cells in the uninjured artery, P<0.001). Profiles of apoptosis and cell proliferation after PTCA were discordant in all layers of the artery except the neointima. These profiles also differed between traumatized and nontraumatized regions of the arterial wall. Immunostaining with cell-type specific markers and TEM analysis revealed that apoptotic cells included vascular smooth muscle cells (VSMCs), inflammatory cells, and adventitial fibroblasts. CONCLUSIONS: These results suggest that the profile of apoptosis and proliferation after PTCA is regional and cell specific, and attempts to modulate either of these events for therapeutic benefit requires recognition of these differences.

Actins↗
PubMed1998

Transforming growth factor-beta1 gene polymorphisms and coronary artery disease.

1. Transforming growth factor-beta1 is a cytokine with a very wide spectrum of biological activities. Previous studies have shown that it is involved in a number of physiological and pathological processes including heart disease. In our study we aimed to scan the transforming growth factor-beta1 locus for polymorphisms and to identify haplotypes significantly associated with a predisposition to coronary atherosclerosis.2. Two patient groups comprising 244 angiographically normal individuals and 655 patients with coronary artery disease were recruited from London and Sheffield. DNA samples from these subjects were screened for mutations in the transforming growth factor-beta1 locus and all subjects were genotyped by a coupled polymerase chain reaction-restriction enzyme digestion method.3. Five polymorphisms have been identified in the transforming growth factor-beta1 gene at positions G-800A, C-509T in the promoter region, Leu10-->Pro, Arg25-->Pro in exon 1 and Thr263-->Ile in exon 5. No significant difference in frequencies for any of the five polymorphisms was found between controls and patients with coronary artery disease. Similarly, there was no correlation between these polymorphisms and hypertension.4. The genotypes of all the individuals participating in the study were assigned to seven main haplotypes of the transforming growth factor-beta1 locus. Based on species comparison data we propose that GCCGC is the ancestral haplotype in humans.5. Our data suggest that these transforming growth factor-beta1 polymorphisms are not associated with coronary artery disease and therefore their presence alone would not be a genetic risk factor for predisposition to coronary artery disease.

Case-Control Studies↗
PubMed1998

Substance misusers remanded to prison--a treatment opportunity?

AIMS: To describe self-reported levels of substance misuse before arrest among remanded prisoners (unconvicted prisoners awaiting trial), to assess their degree of dependency on opiates and stimulants and to record their experiences of treatment in prison. DESIGN: Random selection of subjects from prisons chosen to give a geographical spread across England and Wales; self-report at semi-structured interview, plus examination of the prison medical record. SETTING: Thirteen male prisons, three Young Offenders' Institutions and three womens' prisons. PARTICIPANTS: Nine hundred and ninety-five consenting, unconvicted prisoners, randomly selected from all locations within the prisons: 750 men (9.4% sample) and 245 women (82.2% of all remanded women). MEASUREMENTS: CAGE Questionnaire, Severity of Dependence Scales (SDS) for daily users of opiates and/or stimulants. FINDINGS: Before arrest, 145 (19.3%) men and 72 (29.4%) women had been dependent on street drugs; 91 (12.1%) men and 16 (6.5%) women were solely dependent on alcohol. Seventeen (2.3%) men and four (1.6%) women reported injecting drugs during this imprisonment. Mean SDS scores were 10.6 for opiate and 7.7 for stimulant users. 244 (25%) of all subjects described withdrawal symptoms on reception into custody; 157 (16%) reported being prescribed some symptomatic relief; 235 (24%) requested treatment at interview. CONCLUSIONS: By extrapolation, 1905 people--23% of all unconvicted prisoners--want treatment for substance misuse. This apparent shortfall in provision must be addressed; the rapidity with which remanded prisoners return to the community dictates that prison and community services should be closely linked.

Adolescent↗