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Biomedical subjects

G T Jones

Publications and source records attributed to G T Jones.

At least 19 recordsLinked to original sources
PubMed2006

Is the report of widespread body pain associated with long-term increased mortality? Data from the Mini-Finland Health Survey.

OBJECTIVE: To determine whether an observation in a UK study, that persons with chronic widespread pain are at long-term increased risk of cancer mortality, can be replicated in a different setting. METHODS: Subjects were participants aged >or=30 yrs in the Mini-Finland Health Survey conducted between 1979 and 1980. Information collected included prevalent pains at different joints throughout the body, demographic, anthropometric, lifestyle and occupational factors. During follow-up, until 1994, information on vital status and cause of death was obtained. RESULTS: 7182 persons participated (89.8%). The prevalence of widespread body pain (pain at four or more sites) was 20% in females and 12% in males, and during follow-up there were a total of 1647 deaths. The risk of death was not elevated amongst those with widespread pain [relative risk (RR): 0.86; 95% confidence interval (CI): 0.74-1.00], and in particular, those with widespread pain were at a slightly lower risk of several disease-specific causes of death and cancer death (RR: 0.64; 95% CI: 0.46-0.91). CONCLUSIONS: This study of multiple pains has not confirmed a previous observation of an association between the reporting of widespread pain and subsequent increased risk of cancer death. Differences in the definitions used or, more probably, the population studied, in particular, a larger rural population with more multiple pains related to physical activity may account for the differences.

Adult↗
PubMed2006

Predictors of persistent neck pain after whiplash injury.

OBJECTIVE: To establish the aetiological influences of persistent neck pain following a motor vehicle collision and to construct a model for use in the emergency department for identifying patients at high risk of persistent symptoms. DESIGN: Prospective cohort study. Patients recruited from hospital emergency departments were sent a questionnaire to gather information on various exposures. They were followed up at 1, 3, and 12 months to identify those with persistent symptoms. MAIN OUTCOME MEASURE: Persistent neck pain (pain at 1, 3, and 12 months after collision). RESULTS: The baseline survey included 765 patients. Subsequently, 480 completed a questionnaire at each follow up time point, of whom 128 (27%) reported neck pain on each occasion. Few collision specific factors predicted persistent neck pain. In contrast, a high level of general psychological distress, pre-collision history of widespread body pain, type of vehicle, whiplash associated symptoms, and initial neck disability best predicted the persistence of symptoms. Furthermore, these factors, in combination, accounted for more than a fivefold increase in the risk of persistent neck pain. CONCLUSION: The greatest predictors of persistent neck pain following a motor vehicle collision relate to psychological distress and aspects of pre-collision health rather than to various attributes of the collision itself. With these factors, and those relating to initial injury severity, it is possible to identify a subgroup of patients presenting with neck pain with the highest risk of persistent symptoms. Thus, it is possible to identify whiplash patients with a poor prognosis and to provide closer follow up and specific attention to management in these individuals.

Accidents, Traffic↗
PubMed2005

Does physical trauma lead to an increase in the risk of new onset widespread pain?

OBJECTIVE: To determine the rate of new onset of widespread pain after a traumatic event (motor vehicle crash). METHODS: A prospective cohort study of persons registered with an insurance company who had or had not experienced a motor vehicle crash. All participants were sent a questionnaire to assess pre-crash (or for the non-crash group, prior) psychosocial factors and widespread pain. Participants reporting pre-crash (prior) widespread pain were excluded. At six months, participants were sent a follow up questionnaire to ascertain new prevalent widespread pain. RESULTS: 597 (51%) of participants returned a baseline questionnaire (465 crash and 132 non-crash). Among the cohort who had experienced a crash, the new onset rate of widespread pain six months later was low (8%), though in comparison with the non-crash group there was an increased risk (RR = 1.9 (95% CI, 0.8 to 4.8, adjusted for age and sex)); this was attenuated after adjustment for pre-crash (prior) psychological distress and somatic symptoms (RR = 1.4 (95% CI, 0.5 to 3.2)). CONCLUSIONS: The findings suggest that a motor vehicle crash (as an example of a physically traumatic event) is unlikely to have a major impact on the new onset of widespread pain. Any observed relation may, in part, be explained by psychological distress.

Accidents, Traffic↗
PubMed2005

The methylenetetrahydrofolate reductase C677T polymorphism does not associate with susceptibility to abdominal aortic aneurysm.

OBJECTIVES: To test whether the T variant of the C677T polymorphism in the gene for 5,10-methylenetetrahydrofolate reductase (MTHFR) would associate with three distinct forms of vascular disease, abdominal aortic aneurysm (AAA), coronary artery disease (CAD) and peripheral vascular disease (PVD). BACKGROUND: Increases in homocysteine induce elastolytic activity in the arterial wall, a condition which may favour vascular pathogenesis including aneurysm formation. Homozygosity of the common T variant of the C677T polymorphism in the gene for MTHFR has been shown to associate with increased levels of homocysteine. Thus, this functional polymorphism may lead to an increased propensity to develop cardiovascular disease and, in particular, AAA. METHODS: An association study was conducted across 1207 subjects; 428 patients with AAA, 271 CAD patients, 226 PVD patients and 282 controls being genotyped for the C667T variants of MTHFR. RESULTS: There were no significant differences in the frequency of the MTHFR C677T variant between any of the groups examined. AAA patients who were homozygotes for the 677T allele did, however, appear to have significantly larger aneurysms than C allele carriers. CONCLUSION: This study provides no evidence that the T variant of MTHFR is associated with susceptibility to AAA, CAD or PVD. It may, however, be a contributory factor in AAA severity as indicated by aneurysm size.

Aged↗
PubMed2005

Epidemiology of low back pain in children and adolescents.

It has been estimated that over 80% of the population will report low back pain (LBP) at some point in life, and each year 7% of the adult population consult their GP with symptoms. Prevalence increases with age, reaching a peak during the sixth decade of life. Until recently little was known about LBP at young ages. Clinically it was perceived to be uncommon-with few children consulting because of LBP in primary care. Large prospective epidemiological studies have shown that, in those free of LBP at baseline, the best predictor of future onset is a previous history of LBP. Therefore, to understand the epidemiology of LBP, and what predisposes someone to a trajectory of LBP in adult life, it is important to examine the condition at young ages, to determine factors responsible for onset of initial episodes, and to examine whether LBP in childhood is related to symptoms in adulthood.

Adolescent↗
PubMed2004

Micro-venous valves in the superficial veins of the human lower limb.

It is commonly believed that venous valves are not present in veins smaller than 2 mm in diameter. Venous valves, however, have been identified recently in small veins in several regions of the body. This study was undertaken to determine the size distribution of venous valves in the human lower limb micro-venous circulation. Vascular casts were made from six adult lower limbs and the sampled areas were viewed by scanning electron microscopy. In total, 2,376 valves were identified from 410 cm(3) of subcutaneous tissue. The vast majority (94%) of the valves were in veins less than 300 microm in luminal diameter, with 65% of the valves present in venous channels less than 100 microm in luminal diameter. The smallest valves identified were present in venous channels 18 microm in diameter. All valves were bicuspid and often associated with a tributary. Endothelial cells on the vein wall not associated with a valve were fusiform and arranged parallel to the long axis of the vessel, however, the endothelial cells on the luminal and valve sinus surfaces of the cusp were more polyhedral in shape and showed no obvious pattern of alignment. This study provides direct evidence to show that small superficial veins of the human lower limb do contain abundant venous valves and, for the first time, shows that the majority of these valves are present within venous channels less than 100 microm in luminal diameter.

Aged↗
PubMed2004

Parental pain is not associated with pain in the child: a population based study.

BACKGROUND: Child pain is associated with adverse psychosocial factors. Some studies have shown an association between children's and parental pain. Children may "learn" pain behaviour from their parents. OBJECTIVES: To examine whether an association exists between parent and child pain, and, if so, whether this relationship persists after adjusting for psychosocial difficulties in the child. METHODS: 1326 schoolchildren took part in a questionnaire based, cross sectional survey. Parents of study participants were sent a postal questionnaire. Occurrence of body pain was ascertained using blank body manikins and, in children, psychosocial factors were assessed using the Strengths and Difficulties Questionnaire. Three child-parent pain relationships were examined: any child pain with any parental pain or with parental widespread pain; and child low back pain with parental low back pain. RESULTS: The risk of child pain associated with parental reporting of pain was minor, and non-significant. Even when both parents reported widespread pain, the relative risk of pain in the child, after adjusting for age and psychosocial difficulties, was 1.2 (95% CI 0.5 to 3.2). CONCLUSIONS: Parental pain is not a risk for child pain. Pain behaviour is not learned. Rather, child pain is probably attributable to individual factors and the social environment.

Adolescent↗
PubMed2003

Low back pain in schoolchildren: the role of mechanical and psychosocial factors.

BACKGROUND: Low back pain (LBP) in schoolchildren with no apparent clinical cause is known to be a common problem, but considerably less is understood regarding the aetiology of such pain. AIM: To assess the role of both mechanical and psychosocial factors (including emotional and behavioural problems and other somatic pain complaints) in childhood LBP. METHODS: A cross sectional study was carried out in a population of 1446 schoolchildren aged 11-14 years. Information on these potential risk factors for LBP was sought using a self complete questionnaire and a five day bag weight diary. RESULTS: Mechanical factors such as physical activity and school bag weight were not associated with LBP. However, strong associations with LBP were observed for emotional problems, conduct problems, troublesome headaches, abdominal pain, sore throats, and daytime tiredness. CONCLUSION: Results suggest that psychosocial factors rather than mechanical factors are more important in LBP occurring in young populations and could possibly be a reflection of distress in schoolchildren.

Abdominal Pain↗
PubMed2001

Identification of two susceptibility loci for vascular fragility in the Brown Norway rat.

A trait of vascular fragility, characterized by the formation of abrupt defects within the elastic laminae of the abdominal aorta, has been identified in Brown Norway (BN) rats. These lesions are greatly exacerbated in F(1) rats from a BN x New Zealand genetically hypertensive (GH) intercross, implying that the genetic background provided by the GH rat influences lesion severity. The F(2) progeny of the BN x GH intercross were used to identify susceptibility loci for the lesions as well as exacerbating loci. Two major quantitative trait loci (QTLs) for number of internal elastic lamina lesions were identified on rat chromosomes 5 and 10, with the maximum "log of the odds ratio" (LOD) scores at D5Rat119 (LOD 5.0) and at D10Mit2 (LOD 4.5), respectively, together contributing 33.5% to the genetic variance. Further analysis revealed that the chromosome 10 locus exhibits a dominant mode of inheritance, with BN alleles being associated with increased lesion number (P < 0.0002) compared with GH homozygotes. This locus was in epistasis to a modifier locus on rat chromosome 2 at D2Mit14 (LOD score 2.12). A second major locus was identified on chromosome 5, exhibiting a semidominant mode of inheritance, again with the BN allele being significantly associated with increased lesion number (P < 0.0001). Furthermore, a locus influencing lesion severity was identified on chromosome 3 wherein GH alleles associated with increased severity. This is the first study to identify susceptibility loci for vascular elastic tissue fragility.

Animals↗
PubMed2001

Familial abdominal aortic aneurysms in the Otago region of New Zealand.

PURPOSE: To investigate the familial incidence and phenotypic characteristics of patients with abdominal aortic aneurysms (AAA) in the Otago region of New Zealand. METHODOLOGY: A retrospective audit based pilot study and a prospective study of patients having abdominal aortic aneurysm repair from September 1988 to September 1999 was performed. RESULTS: 248 probands were enrolled, of which 19.4% had one or more first degree relative affected. The age at diagnosis of the familial (70.2) and non-familial (70.5) patients was similar. The proportion of females was increased in the familial subgroup. Hypercholesterolaemia was the only phenotypic feature to differentiate familial from non-familial patients and was associated with an earlier age of presentation. In the familial families, brothers were the most common relative affected and 77% of the families had two patients with AAA. CONCLUSION: 19.4% of patients operated on in the Otago area for AAA had a familial component to their aneurysm.

Age Distribution↗
PubMed2000

Association of the 4G/5G polymorphism in the promoter region of plasminogen activator inhibitor-1 with abdominal aortic aneurysms.

PURPOSE: A familial component has previously been identified in 11% to 20% of patients with abdominal aortic aneurysms (AAAs). The genetic basis of familial AAA remains elusive, however. Matrix metalloproteinases have been implicated in aneurysm development; and plasmin, a serine protease, activates metalloproteinases. Plasminogen activator inhibitor-1 (PAI-1) regulates plasmin activation through the tissue plasminogen activators. A polymorphism within the promoter area of PAI-1 has been described that modifies PAI-1 expression and consequently plasminogen activation. The 4G homozygous variant is associated with increased PAI-1 expression and consequently reduced plasmin activity and therefore may be selected against in-familial AAA. The purpose of this study was to investigate the incidence of the 4G/5G insertion/deletion polymorphism in the promoter area of the PAI-1 gene in a population with AAA. METHODS: Patients seen at a tertiary referral center for repair of abdominal aortic aneurysms were recruited. DNA was extracted from blood. Primers were designed to amplify a 99 (5G)-base pair (bp) and a 98 (4G)-bp fragment bracketing the polymorphism. The 5' primer was mutated to allow a restriction endonuclease to cleave the 5G polymorphism into a 77-bp and a 22-bp fragment. Samples were run on agarose gels and stained with ethidium bromide. RESULTS: One hundred ninety patients with AAAs, including 39 patients with strong family histories and 163 controls were examined. The frequency of the 4G:5G alleles in the AAA population and in the control population was 0.6:0.4. However, 26% of patients with familial AAA were homozygous 5G compared with 13% of the control population. The 4G-allele frequency was 0.47 in the familial AAAs, compared with 0.62 in the nonfamilial patients (P =.02) and 0.61 in the control population (P =.03). CONCLUSION: The selection against the 4G4G genotype in the familial AAA population may indicate a role for PAI in the development of AAA in this population.

Aged↗
PubMed2000

Indicator-based systems of performance management in the National Health Service: a comparison of the perceptions of local- and national-level managers.

Historically, the UK Government has policed the use of National Health Service (NHS) resources through the centralization of control. With the majority of resource-draining decisions being taken by clinicians, however, professional financial accountability is becoming more important within the NHS management structure. Variations in clinical performance can be monitored through the use of performance indicators, although these are not without their problems. The use of league tables of such indicators in the national press is now infamous and there is much anecdotal evidence about the intraorganizational conflict arising from the use of such tables. A questionnaire survey and interview study of clinical directors, clinical service directors and business managers in several Scottish NHS Trusts was undertaken to ascertain the perceptions of local-level managers on the issue of performance indicators. Interviews were also carried out with a number of personnel in the Scottish Office Department of Economics and Information, the Division of Health Gain and the Finance Directorate. This paper explores the differences between the perceptions of the managers at these two levels of the NHS with regards to issues of performance measurement, intraorganizational conflict and corporate vision.

Administrative Personnel↗
PubMed1999

Venous morphology predicts class of chronic venous insufficiency.

OBJECTIVES: this study aimed to determine specific morphological differences in long saphenous veins from patients with various grades of chronic venous insufficiency. DESIGN: comparable veins from a control group were compared with patients with either primary varicose veins or those with associated skin changes including venous ulcers. MATERIALS: below-knee segments of saphenous vein were examined from a total of 64 patients. METHODS: veins were examined for elastic-tissue disruption and endothelial-cell changes and comparisons made between clinical groups. RESULTS: elastic-tissue disruption, as measured by fragmentation of the elastic lamina and the percentage of the intimal-medial boundary containing elastin, increased with increasing severity of venous disease. Moreover, endothelial cells became more densely packed, as measured by endothelial cell and endothelial-cell nuclei density, with increasing severity of disease. Other measures such as the density of multinucleated "giant" endothelial cells and the number of nuclei per "giant" cell did not correlate with venous disease, however. CONCLUSIONS: this study demonstrates that several morphological characteristics of superficial saphenous veins correlate with severity of venous disease. In particular, the alterations to the structure of elastic tissue within these veins appears indicative of the progressive nature of chronic venous insufficiency.

Aged↗
PubMed1998

Venous endothelial changes in therapeutic arteriovenous fistulae.

Specimens of veins of therapeutic arteriovenous fistulae from five patients were examined by an en face immunohistochemical technique to investigate endothelial morphology and the presence of the vasoactive peptide endothelin-1 (ET-1). These were compared with control segments of long saphenous veins from six patients. Venous endothelium from the arteriovenous shunts was mostly intact even overlying phlebosclerotic plaques. Occasional small areas of denudation, with associated platelets, were present in the depressions of 'jet' lesion however. The endothelial cells were generally elongated and interspersed with foci of polyhedral cells. The control saphenous veins contained elongated endothelial cells without detectable denudation. Image analysis of histological sections of veins from the shunts indicated significantly less intact elastic tissue than control veins but greater mononucleated endothelial cell density in en face preparations. ET-1 staining was considerably stronger in endothelium from the fistulae than in the control saphenous veins and was most intense over the raised crescentic ridges of jet lesions, stenoses and phlebosclerotic plaques. Endothelial mitoses and cells with hyperchromatic nuclei stained more strongly for ET-1 than surrounding cells. These results indicate that the endothelial cells lining veins associated with arteriovenous fistulae are dynamically altered by the increased haemodynamic stresses associated with these shunts. Furthermore ET-1 may act as a localising factor associated with intimal thickening at sites of 'jet' lesions, stenosis and phlebosclerosis.

Adult↗
PubMed1996

Endothelin-1 is increased overlying atherosclerotic plaques in human arteries.

The distribution of Endothelin-1 (ET-1), a potent vasoactive peptide, within endothelium of human atherosclerotic arteries was examined using a novel en face immunohistochemical technique. The vast majority of endothelial cells were immunoreactive for ET-1. Staining intensity was increased in areas overlying atherosclerotic plaques, calcified media, fatty streaks and about flow dividers, compared with adjacent regions. Multinucleated 'giant' endothelial cells were more common in regions containing strong ET-1 staining than elsewhere. Clusters of leucocytes (probably monocytes) were frequently observed adhering to the endothelial monolayer but not neighbouring regions of denudation. Occasionally underlying macrophage/foam cells and smooth muscle cells were exposed to the surface and included in the en face (Häutchen) preparation. Smooth muscle cells did not stain for ET-1 while macrophages and the larger foam cells were positive for ET-1. These results support the hypothesis that expression of ET-1, at sites containing atheromatous disease, may be involved in the development of atherosclerosis.

Aged↗
PubMed1996

The effect of L-dopa on the healing of a rat mandibular defect.

PURPOSE: This study was designed to evaluate the effect of L-dopa on healing of a surgically created bony defect in the adult male rat. MATERIALS AND METHODS: Thirty-six animals underwent surgery to create a 4-mm circular defect in the left mandibular angle. They were then randomly divided into two equal groups, one receiving 0.2 g/kg/day of L-dopa for 10 days by orogastric gavage, the other group acting as a control. Six experimental and six control animals were killed at 2 weeks, and five experimental and six control animals were killed at 4 and 6 weeks postoperation. Healing was classified as complete, partial, or incomplete based on gross and radiographic observations. RESULTS: Gross observation of the experimental mandibles showed five completely healed defects (31.25%), five partially healed defects (31.25%), and six defects with no healing (37.5%). Control mandibles showed three defects with partial healing (16.67%) and 15 with no healing (83.33%). Radiographs were taken of randomly chosen mandibles in each control and experimental group. Of the six experimental mandibles, one showed no healing, three showed partial healing, and two showed complete healing of the defect. The six control mandibles showed three defects with no bone formation and three with partial healing. CONCLUSIONS: The data from this study indicate that L-dopa had a promoting effect on the bony healing of defects in the rat mandible.

Administration, Oral↗