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T J Ryan

Publications and source records attributed to T J Ryan.

At least 19 recordsLinked to original sources
PubMed2007

What are subcutaneous adipocytes really good for?

Our acute awareness of the cosmetic, psychosocial and sexual importance of subcutaneous adipose tissue contrasts dramatically with how poorly we have understood the biology of this massive, enigmatic, often ignored and much-abused skin compartment. Therefore, it is timely to recall the exciting, steadily growing, yet underappreciated body of evidence that subcutaneous adipocytes are so much more than just 'fat guys', hanging around passively to conspire, at most, against your desperate attempts to maintain ideal weight. Although the subcutis, quantitatively, tends to represent the dominant architectural component of human skin, conventional wisdom confines its biological key functions to those of energy storage, physical buffer, thermoregulation and thermoinsulation. However, already the distribution of human superficial adipose tissue, by itself, questions how justified the popular belief is that 'skin fat' (which actually may be more diverse than often assumed) serves primarily thermoinsulatory purposes. And although the metabolic complications of obesity are well appreciated, our understanding of how exactly subcutaneous adipocytes contribute to extracutaneous disease - and even influence important immune and brain functions! - is far from complete. The increasing insights recently won into subcutaneous adipose tissue as a cytokine depot that regulates innate immunity and cell growth exemplarily serve to illustrate the vast open research expanses that remain to be fully explored in the subcutis. The following public debate carries you from the evolutionary origins and the key functional purposes of adipose tissue, via adipose-derived stem cells and adipokines straight to the neuroendocrine, immunomodulatory and central nervous effects of signals that originate in the subcutis - perhaps, the most underestimated tissue of the human body. The editors are confident that, at the end, you shall agree: No basic scientist and no doctor with a serious interest in skin, and hardly anyone else in the life sciences, can afford to ignore the subcutaneous adipocyte - beyond its ample impact on beauty, benessence and body mass.

Adipocytes↗
PubMed2005

Regionalization: a strategy that will assist with bovine tuberculosis control and facilitate trade.

It is expected that the revised chapter on bovine tuberculosis in the Terrestrial Animal Health Code of the Office Internationale des Epizooties (OIE) will embrace regionalization as a functional means of assisting countries, states or regions to meet the requirements for freedom from tuberculosis and to facilitate trade. The benefits and applications of regionalization, which comprises zoning and compartmentalisation, are discussed. Regionalization requires that a country's veterinary administration is able to implement transparent and auditable biosecurity measures that will ensure that the tuberculosis-free status of a subpopulation of cattle is maintained despite the presence of infection in another cattle subpopulation, or in other domestic or wild animal species. Zoning, which requires cattle subpopulations to be separated by geographic boundaries, provides a practical basis whereby countries, states or regions, can progress towards freedom from tuberculosis, regardless of the source of infection for defined cattle subpopulations. Compartmentalisation however, requires that husbandry or management practices will be used to prevent a tuberculosis-free cattle subpopulation from contacting interspecific and intraspecific sources of infection. This will be difficult to achieve except for specialised cases such as artificial breeding centers.

Animal Husbandry↗
PubMed2005

Advances in understanding disease epidemiology and implications for control and eradication of tuberculosis in livestock: the experience from New Zealand.

A deteriorating tuberculosis problem in cattle and deer in New Zealand has been halted and then reversed over the last decade. Mycobacterium bovis infection in both wild and domestic animal populations has been controlled. This has been achieved by applying a multi-faceted science-based programme. Key features of this have been a comprehensive understanding of the epidemiology of tuberculosis in animals, confidence in sampling wild animal populations, effective application of diagnostic tests in cattle and deer, and the ability to map M. bovis genotypes.

Animal Population Groups↗
PubMed2005

An analysis of nursing activity in a day care and inpatient dermatology service.

The nursing context within which dermatological treatments are provided has received limited investigation. This activity analysis survey examined how nursing time is organized (n=17 nurses) within in- and out-patient day care services in a hospital teaching dermatology department, using a newly developed standardized tool over a 24-week period. The setting was a day care and inpatient facility in a UK dermatology department. Patients (n=108) referred to these services for day care or inpatient care over 24 weeks, excluding emergencies, were recruited consecutively; 76% (n=82) were seen during this time. Most patients (>95%) were referred for clearance of an acute episode of a chronic skin condition and specifically education. The total mean time in contact with the nursing service (mean hours/case) was 43.1 for inpatient and 6.6 for day care. Time in day care was mainly spent (mean hours/case) on direct care (living activities and dermatological treatments) (4.3), followed by teaching (2) and support (1.6). The pattern of inpatient care was similar. A profile has been derived that is indicative of how dermatology nurses spend their time in day and inpatient care. There may be scope for day care nursing to make more effective use of education opportunities to support patient self-management.

Ambulatory Care Facilities↗
PubMed2004

Nurse-led education sets out to improve patient concordance and prevent recurrence of leg ulcers.

OBJECTIVE: This study evaluated the effects of a structured nurse-led education programme that aimed to improve patient concordance and prevent venous leg ulcer recurrence. METHOD: The design was quasi-experimental. Subjects (average age: 80) had venous leg ulceration that had healed within the previous two years, and were cared for at home by a district nurse. Data were available on 49 patients with 97 legs, 72 of which had had venous leg ulcers. Patients were divided into two groups: a control group, which received 'usual' care, and experimental group, which was exposed to the education programme. Recurrence rates, the effects of the education on patient behaviour and the effect on recurrence of having both ankle movement and general mobility were measured over one year. RESULTS: Patients in the experimental group experienced significantly less recurrence over the year (log rank test = 8.28, p = 0.004). To control for differences in mobility and ankle movement in the control and experimental groups at baseline, simultaneous logistic regression analysis was undertaken. This revealed a significant advantage for patients in the experimental group (p = 0.035; OR = 4.45, 95% CI = 1.11-17.74), who spent more time with their legs elevated each day. This difference was sustained throughout the 52 weeks (f = 2.88, p = 0.015). Those who had both full ankle movement (> 60 degrees) and full mobility (without aid) had significantly less recurrence (p = 0.042). Education had no significant effect on the amount of time patients wore compression hosiery (f = 2.1). CONCLUSION: A structured nurse-led patient concordance programme is effective in preventing venous leg ulcer recurrence and increasing the time patients spend with their legs elevated at heart level. Having both full ankle movement and full mobility reduces the risk of recurrence.

Activities of Daily Living↗
PubMed2004

How echographic image analysis of venous oedema reveals the benefits of leg elevation.

OBJECTIVE: Venous insufficiency, leading to venous oedema, is a key pathogenic factor for the non-healing of venous leg ulcers. This study aimed to evaluate the effects of leg elevation on venous oedema. METHOD: Ten patients aged 44-89 years (median: 61) with leg oedema had high-frequency B-mode ultrasound scanning and digital image analysis before and after three to four hours of leg elevation. The echographic image analysis system was used, where oedema is represented by the hypoechogenic part of the image--that is, the total number or density of low echogenic pixels (LEPs) in a particular area. RESULTS: Compared with pre-elevation, the volume of the lower leg decreased by 2.9% +/- 0.6 (138 cm3 +/- 39) after three to four hours' elevation (p < 0.05). After elevation, the LEPs in the upper, middle and lower sites of the limb decreased by 8.8%, 15.6% and 17.3% respectively, reaching statistical significance (p < 0.05) in the lower site. The ratio of LEPs in the upper and lower dermis in the upper, middle and lower sites decreased by 30.3%, 45.8% and 22.5% respectively. This was significant in both the middle and lower sites (p < 0.01). After elevation dermal thickness increased by 0.047 mm, 0.194 mm and 0.232 mm respectively. This change was statistically significant in the middle (p < 0.05) and lower sites of the limb (p < 0.01). CONCLUSION: LEPs are a sensitive marker of dermal oedema and its effects. Leg elevation is extremely effective in reducing oedema, even if only for three to four hours.

Adult↗
PubMed2003

Use of mycobacterial peptides and recombinant proteins for the diagnosis of bovine tuberculosis in skin test-positive cattle.

More accurate tests are required to test cattle which have reacted positively in the tuberculin skin test. For this purpose, a range of mycobacterial antigens, MPB59, MPB64, MPB70, MPB83, ESAT-6 and CFP10, were used either as recombinant proteins or as synthetic peptides in the whole blood interferon-gamma (IFN-gamma) test. Groups of uninfected cattle with typical 'non-specificity' problems were targeted, in particular animals with skin tuberculosis, animals vaccinated against Johne's disease and animals that were positive in the standard purified protein derivative (PPD)-based IFN-gamma test. The two study groups consisted of 74 Mycobacterium bovis-culture positive animals and 72 uninfected animals, all of which tested positive in the caudal fold tuberculin skin test eight to 28 days before the blood test. The use of combinations of ESAT-6 and CFP10 antigens, either as recombinant proteins or peptides, detected similar percentages of M bovis-infected animals as the PPD-based IFN-gamma test, but produced significantly fewer false positive reactions. The PPD-based IFN-gamma test was very effective in differentiating animals vaccinated against Johne's disease that were skin-test positive from those with bovine tuberculosis, and the use of PPD or specific mycobacterial antigens minimised the number of false positive reactions in animals with skin tuberculosis.

Amino Acid Sequence↗
PubMed2002

Lymphatics in leprosy: relationship to elastic fibres and observations following intra-lesional injections of colloidal carbon.

An investigation of skin lymphatics in leprosy has been undertaken. Examination of 62 skin biopsies from 31 patients with various classifications of leprosy has revealed dilated initial lymphatics within granulomas of lepromatous leprosy, but no significant abnormalities in non-lepromatous disease or in non-granulomatous skin. Colloidal carbon injected intra-lesionally failed to appear within granulomas, but could be seen in lymphatics in non-granulomatous dermis. Elastic fibres were also absent within granulomas. AFB were clearly identified within endothelial cells of initial lymphatics. We suggest lymphatic malfunction may be compartmental, existing only within the granulomas and not in the surrounding normal appearing dermis.

Carbon↗
PubMed2001

Use of ESAT-6 in the interferon-gamma test for diagnosis of bovine tuberculosis following skin testing.

The whole blood interferon-gamma (IFN-gamma) test has proven to be a practical ancillary test for re-testing cattle for bovine tuberculosis 8-28 days following tuberculin skin testing. An improvement in the specificity of the IFN-gamma test could further reduce culling of false positive animals. The primary aim of this study was to evaluate a single mycobacterial antigen, ESAT-6 in the IFN-gamma test for use in skin test-positive cattle. These skin test-positive cattle comprised 51 Mycobacterium bovis-infected animals from tuberculosis-infected herds and 85 non-infected animals from tuberculosis-free herds. The test based on ESAT-6 had a higher specificity than the test based on purified protein derivative (PPD) tuberculin, but this was offset by a small decrease in sensitivity. Use of a lower cut-off in the ESAT-6-based test improved the sensitivity, while still maintaining a very high specificity. A secondary aim in the study was to assess the ESAT-6 and PPD-based tests for detecting bovine tuberculosis in skin test-negative animals from a persistently infected herd. The PPD-based test detected the majority of the lesioned or M. bovis-culture positive animals, while the ESAT-6-based test detected a smaller proportion. The false negatives in the IFN-gamma test from both the skin test-negative and positive groups were predominantly M. bovis-culture positive animals with no visible lesions. The current study has shown that a defined specific antigen such as ESAT-6 can markedly improve the specificity of the IFN-gamma test for re-testing skin test-positive animals. An ESAT-6-based IFN-gamma test could be particularly useful to reduce the false positive rate, yet still maintain an acceptable level of sensitivity.

Animals↗
PubMed2001

Percutaneous coronary intervention in st-elevation myocardial infarction.

This review traces the development of coronary angioplasty as a direct, primary means of establishing reperfusion in an acutely occluded infarct-related artery. As a therapeutic strategy for the early management of patients with ST-elevated acute myocardial infarction, this mechanical-invasive procedure arose virtually simultaneously with the demonstration that intravenous administration of fibrinolytic agents to such patients results in a relative reduction in early mortality by as much as 25% to 30%. Over the past 15 years, more than a dozen randomized, controlled trials have investigated the question, "Which is the better means of administrating reperfusion therapy?" The recent demonstration that the combination of coronary stenting plus glycoprotein IIb/IIIa inhibitors used in the early stages of ST-elevation acute myocardial infarction salvages more myocardium than the administration of front-loaded tissue plasminogen activator offers a convincing answer. This is further supported by the evidence that clinical outcomes also improved in these patients, with the greater improvement in ventricular function. It is likely, however, that the development of newer pharmacologic agents plus the combination of both strategies will keep this a hotly debated issue for some time to come.

Angioplasty, Balloon, Coronary↗
PubMed2001

Validating recommendations for coronary angiography following acute myocardial infarction in the elderly: a matched analysis using propensity scores.

We determined whether adherence to recommendations for coronary angiography more than 12 h after symptom onset but prior to hospital discharge after acute myocardial infarction (AMI) resulted in better survival. Using propensity scores, we created a matched retrospective sample of 19,568 Medicare patients hospitalized with AMI during 1994-1995 in the United States. Twenty-nine percent, 36%, and 34% of patients were judged necessary, appropriate, or uncertain, respectively, for angiography while 60% of those judged necessary received the procedure during the hospitalization. The 3-year survival benefit was largest for patients rated necessary [mean survival difference (95% CI): 17.6% (15.1, 20.1)] and smallest for those rated uncertain [8.8% (6.8, 10.7)]. Angiography recommendations appear to select patients who are likely to benefit from the procedure and the consequent interventions. Because of the magnitude of the benefit and of the number of patients involved, steps should be taken to replicate these findings.

Aged↗
PubMed2001

The effect of mechanical forces (vibration or external compression) on the dermal water content of the upper dermis and epidermis, assessed by high frequency ultrasound.

An ultrasound scanner, is used to detect changes in water content of the upper dermis. This has previously been found to vary with age and to show diurnal variation. Furthermore, oedema due to venous disease can be shown, using this technique, to respond to elevation. In this study, the water content of the upper dermis and epidermis of the leg in 16 subjects is increased following vibration for 10 minutes using a passive exercise system. A study of pressure applied to the skin of the heel for 10 minutes in 14 volunteers also showed an increase in water content of epidermis and dermis in young persons, but less so in the elderly. It is postulated that the anatomical structure of the vascular bed of the upper dermis predisposes to transsudation when pressure to the skin is applied, thereby maintaining the resilience of the skin in the young, but less so in the elderly.

Adult↗