Chlamydia and coronary heart disease.
Explore the source record for details and available documents.
Chlamydia Infections↗
Biomedical subjects
A Evans
Publications and source records attributed to A Evans.
Cerebral [15O]water clearance in humans determined by PET: I. Theory and normal values.
When used to measure blood flow in the brain, water leaves a residue in the vascular bed that influences the estimation of blood flow by current methods. To assess the magnitude of this influence, we developed a two-compartment model of blood flow with separate parameters for transport and vascular distribution of brain water. Maps of the water clearance, K1 into brain tissue, separated from the circulation by a measurably resistant blood-brain barrier (BBB), were generated by time-weighted integration. Depending on the validity of the assumptions underlying the two-compartment model presented here, the maps revealed a significant overestimation of the clearance of water when the vascular residue was ignored. Maps of Vo, the estimate of the apparent vascular distribution volume of tracer H2(15)O, clearly revealed major cerebral arteries. Thus, we claim that the accumulation of radioactive water in brain tissue also reflects the volume of the arterial vascular bed of the brain.
Body Water↗
The reproducibility of urinary growth hormone measurement in children undergoing adenotonsillectomy: a pilot study.
The reproducibility of urinary growth hormone levels in normal children and in children undergoing adenotonsillar surgery was investigated. Thirty normal children and 32 children pre- and post-adenotonsillectomy had overnight urinary growth hormone levels measured on two consecutive nights using the technique of immunoradiometric assay. There was no significant difference when levels in each of these groups were compared. Therefore, the results were pooled (n = 94) and the correlation coefficient comparing levels obtained on the first and the second consecutive nights sample was calculated, r = 0.644 (P < 0.001). This work suggests that studies of urinary growth hormone levels in children give reproducible results. Further investigation of this technique as a screening or diagnostic procedure in the clinical setting can now be more widely evaluated.
Adenoidectomy↗
DNA polymorphisms in linkage disequilibrium at the 3' end of the human APO AII gene: relationships with lipids, apolipoproteins and coronary heart disease.
Two investigations were undertaken to analyze the 3' region of the apolipoprotein AII (Apo AII) gene in patients with myocardial infarction (MI) and controls. Previous studies have suggested that a MspI polymorphism in this gene may be associated with hypertriglyceridaemia, high levels of HDL cholesterol and Apo AII. To verify this hypothesis, the distribution of MspI genotypes and their possible associations with several plasma lipid variables were studied in 882 subjects (411 cases with MI and 471 controls) from the ECTIM study. There were no differences in genotype and allele frequencies between cases and controls, and no differences in lipid variable levels in controls carrying the less frequent MspI allele vs other controls. Using single-strand conformation polymorphism (SSCP) analysis, we detected a new polymorphism which caused by a C-to-T transition located in the third intron near the splice junction site (acceptor). This polymorphism modifies a Bst N1 restriction site. The ECTIM population was screened for this new marker, and no significant associations with MI and plasma lipid levels were found. Our results suggest that these two variants located in the coding region of the Apo AII gene are unlikely to contribute significantly to the level of plasma lipid variables and the risk of coronary heart disease (CHD) in the European population.
Adult↗
Preliminary results from follow-up of a large-scale population survey of antibodies to gliadin, reticulin and endomysium.
UNLABELLED: Coeliac disease is often under-diagnosed, particularly in cases which are atypical or asymptomatic. OBJECTIVE: The aim of this study was to comprehensively assess the prevalence and clinical profile of adult coeliac disease in our community. METHODS: One-hundred-and-thirteen subjects from the most recent MONICA (multinational MONItoring of trends and determinants in CArdiovascular disease)1991/2 survey with positive serology were followed up 3 years after initial screening and assessed by means of (i) a clinical questionnaire, (ii) screening blood tests, and (iii) jejunal biopsy. RESULTS: Forty-six subjects (21 male, mean age 51 years) have been followed up to date. Prior to follow-up, two of these subjects were diagnosed as having coeliac disease. Ten (3 male, mean age 51 years) of 44 subjects had enteropathy. Three of these 10 subjects were relatively asymptomatic, 3 had folate deficiency and 3 had iron deficiency. Thus 12 of the 1823 initially screened had enteropathy consistent with coeliac disease. CONCLUSIONS: Coeliac disease is more prevalent than previous estimations and was found to be at least 1 in 152.
Adult↗
Pseudoephedrine is without ergogenic effects during prolonged exercise.
This study was designed to measure whether a single dose of 120 mg pseudoephedrine ingested 120 min before exercise influences performance during 1 h of high-intensity exercise. The effects of exercise on urinary excretion of the drug were also studied. Ten healthy male cyclists were tested on two occasions, separated by at least 7 days, by using a randomly assigned, double-blind, placebo-controlled, crossover design. Exercise performance was tested during a 40-km trial on a laboratory cycle ergometer, and skeletal muscle function was measured during isometric contractions. On a third occasion, subjects ingested 120 mg pseudoephedrine but did not exercise [control (C)]. Pseudoephedrine did not influence either time trial performance [drug (D) vs. placebo: 58.1 +/- 1.4 (SE) vs. 58.7 +/- 1.5 min] or isometric muscle function. Urinary pseudoephedrine concentrations were significantly increased 1 h after exercise (D vs. C: 114.3 +/- 27.2 vs. 35.4 +/- 13.1 micrograms/ml; P < 0.05). Peak plasma pseudoephedrine concentrations (P < 0.05) but not time taken to reach peak plasma concentrations or the area under the plasma pseudoephedrine concentration vs. time curve was significantly increased in the total group with exercise (D vs. C). In three subjects, plasma pseudoephedrine concentrations were not influenced by exercise. Only these subjects showed increased urinary pseudoephedrine excretion during exercise. We conclude that a single therapeutic dose of pseudoephedrine did not have a measurable ergogenic effect during high-intensity exercise of 1-h duration, but plasma drug concentrations and urinary excretion were altered by exercise. These findings have practical relevance to doping control regulations in international sporting competitions.
Adult↗
Neural systems for tactual memories.
1. The aim of this study was to investigate the neural systems involved in the memory processing of experiences through touch. 2. Regional cerebral blood flow was measured with positron emission tomography by means of the water bolus H2(15)O methodology in human subjects as they performed tasks involving different levels of tactual memory. In one of the experimental tasks, the subjects had to palpate nonsense shapes to match each one to a previously learned set, thus requiring constant reference to long-term memory. The other experimental task involved judgements of the recent recurrence of shapes during the scanning period. A set of three control tasks was used to control for the type of exploratory movements and sensory processing inherent in the two experimental tasks. 3. Comparisons of the distribution of activity between the experimental and the control tasks were carried out by means of the subtraction method. In relation to the control conditions, the two experimental tasks requiring memory resulted in significant changes within the posteroventral insula and the central opercular region. In addition, the task requiring recall from long-term memory yielded changes in the perirhinal cortex. 4. The above findings demonstrated that a ventrally directed parietoinsular pathway, leading to the posteroventral insula and the perirhinal cortex, constitutes a system by which long-lasting representations of tactual experiences are formed. It is proposed that the posteroventral insula is involved in tactual feature analysis, by analogy with the similar role of the inferotemporal cortex in vision, whereas the perirhinal cortex is further involved in the integration of these features into long-lasting representations of somatosensory experiences.
Adult↗
Polymorphisms of the transforming growth factor-beta 1 gene in relation to myocardial infarction and blood pressure. The Etude Cas-Témoin de l'Infarctus du Myocarde (ECTIM) Study.
Transforming growth factor-beta 1 (TGF-beta 1) plays an important role in the modulation of cellular growth and differentiation and the production and degradation of the extracellular matrix. A number of experimental results suggest that TGF-beta 1 may be involved in cardiovascular physiopathology. In the present study, we assessed whether the TGF-beta 1 gene is a candidate gene for coronary heart disease or hypertension. We screened the coding region and 2181 bp upstream of the TGF-beta gene for polymorphisms and identified seven polymorphisms: 3 in the upstream region of the gene at positions -988, -800, and -509 from the first transcribed nucleotide; 1 in a nontranslated region at position +72; 2 in the signal peptide sequence Leu10-->Pro, Arg25-->Pro; and 1 in the region of the gene coding for the precursor part of the protein not present in the active form, Thr263-->Ile. We analyzed these TGF-beta 1 polymorphisms in 563 patients with myocardial infarction and 629 control subjects from four regions in Northern Ireland and France. The Pro25 allele was more frequent in patients than in control subjects in Belfast (P < .01) and Strasbourg (P < .05). The TGF-beta 1 polymorphisms were not associated with the degree of angiographically assessed coronary artery disease in patients. The presence of a Pro25 allele was associated with a lower systolic pressure in the four control groups (P < .002), and a history of hypertension was significantly less frequent in homozygotes or heterozygotes for Pro25 than in hormozygotes for Arg25 (odds ratio, 0.43, 95% confidence interval, 0.19 to 0.92; P < .03). Since the Pro25 allele was associated with an increased risk of myocardial infarction and a reduced risk of hypertension, we favor a cautious interpretation of these apparently inconsistent results. Other studies will need to verify whether these associations are real.
Adult↗
The biting midge of the West Highlands: fifty years of research.
The biting midge of the West Highlands belongs to the family Ceratopogonidae and approximately 150 species are known to exist in Britain. All of the flies are of minute size and slender build with wings which fold over the back. The females have biting mouthparts including a needle sharp proboscis with scissor type mandibles. The males do not bite. The Ceratopogonidae devours other small insects, some feed on plant juices, others pierce the wing veins of butterflies and some attack juicy caterpillars. Only three genera are bloodsuckers and of these only Culicoides occurs in Britain. The members of this genus are classified by the pattern of wing venation and the spots on the wings. Edwards' gives a detailed table of these characteristics. The commonest species in Scotland is C. impunctatus, although others have been met with on Skye.
Animals↗
Should all patients with ureteric colic be admitted?
Explore the source record for details and available documents.
Colic↗
Blood pressure control of drug treated hypertension in 18 general practices.
This study examined the blood pressure (BP) control and number of drugs prescribed for a sample of hypertensive patients from 18 practices in Northeast England. Out of a total of 35,379 registered patients aged 40-69 years, 2995 (8.5%) were on treatment for hypertension. Data was abstracted from the practice records of a random sample of 691 patients. Using British Hypertension Society standards, BP control was optimal for systolic pressure (less than 160 mm Hg) in 469 (68%), and for diastolic pressure (less than 90 mm Hg) in 345 (50%), but only 269 (39%) had optimally controlled systolic and diastolic pressures. Sixty-one per cent were taking one drug and 39% two or more; 82% of patients aged 40-49 years but only 61% of those aged 60-69 years had optimally controlled systolic pressures. Forty-three per cent of the 40 to 49-year-old group and 56% of the 60 to 69-year-old group had optimally controlled diastolic pressures. A strong inverse relationship was found between age and systolic BP control but there was no association between age and diastolic pressure or the number of drugs being prescribed. Sub-optimal BP control is a major problem and remedial strategies should stress the greater gain from treating older patients.
Adult↗
Neural correlates of mental transformations of the body-in-space.
Regional cerebral blood flow was measured with positron emission tomography in human subjects during the performance of a task requiring mental rotation of their hand and a perceptually equivalent control task that did not require such a process. Comparison of the distribution of cerebral activity between these conditions demonstrated significant blood flow increases in the superior parietal cortex, the intraparietal sulcus, and the adjacent rostralmost part of the inferior parietal lobule. These findings demonstrated that, in the human brain, there is a specific system of parietal areas that are involved in mental transformations of the body-in-space.
Adult↗
Myocardial infarction, Arg 506 to Gln factor V mutation, and activated protein C resistance.
Explore the source record for details and available documents.
Adult↗
Stable amplification of the S-adenosylmethionine decarboxylase gene in Chinese hamster ovary cells.
A Chinese hamster ovary cell subline (CHO/664) > 1000-fold resistant to the S-adenosylmethionine decarboxylase (AdoMetDC) inhibitor, CGP-48664 (4-(aminoiminomethyl)-2,3-dihydro-1H-inden-1-one diaminomethylenehydrazone), has been developed and characterized. The cells were also cross-resistant to the highly specific nucleoside analog inhibitor of AdoMetDC, MDL-73811. These unique cells stably overexpress AdoMetDC due to a 10-16-fold amplification of the AdoMetDC gene, which resulted in a similar increase in AdoMetDC transcript levels. In the presence of 100 microM CGP-48664, the CHO/664 cells displayed AdoMetDC activities similar to the parental line. Following removal of the inhibitor, AdoMetDC activity increased steadily over 20 days to 10-12 times that found in parental CHO cells. Decarboxylated (dc) AdoMet pools accumulated rapidly from < 5 pmol/10(6) cells to approximately 1000-1500 pmol/10(6) cells at 3 days due to diffusion away of intracellular inhibitor and to the depletion of putrescine and spermidine as aminopropyl acceptors in dcAdoMet-mediated synthase reactions. Polyamine pools shifted as putrescine, and spermidine pools were processed forward to spermine. During the period from 3 days to 20 days, dcAdoMet pools fell steadily and eventually stabilized at 100-200 pmol/10(6) cells. Providing excess putrescine at this time as an aminopropyl acceptor rapidly lowered dcAdoMet pools and led to a near normalization of polyamine pools, indicating that both dcAdoMet and putrescine are essential in maintaining steady-state polyamine pool profiles. As with cell line variants that overproduce ornithine decarboxylase, polyamine transport was found to be increased in CHO/664 cells due to an apparent inability of the system to down-regulate polyamine transport in response to polyamine excess. Given the unique metabolic disturbances seen in these cells, we anticipate that in addition to providing a useful system for evaluating the specificity of newly developed AdoMetDC inhibitors, they will undoubtedly prove valuable for investigating the various regulatory interrelationships involved in polyamine homeostasis and possibly other aspects of purine metabolism.
Adenosylmethionine Decarboxylase↗
Care-seeking among individuals with chronic low back pain.
STUDY DESIGN: This was a stratified, random telephone survey of adults in North Carolina. OBJECTIVE: To determine the prevalence of chronic low back pain and the extent to which treatment is sought for this condition. SUMMARY OF BACKGROUND DATA: Chronic low back pain is a major problem. Previous studies often have combined acute and chronic back pain. METHODS: Telephone interviews regarding back pain were conducted with 4437 North Carolina adults during 1992. RESULTS: Chronic back pain affects 3.9% of the North Carolina population. Thirty-four percent considered themselves permanently disabled and 52% assessed their overall health as fair or poor. The median number of bed-disability days per year was three. Seventy-three percent saw a health care provider. Of those who sought care, 91% saw a medical doctor, 29% saw a physical therapist, and 25% saw a chiropractor. Use of technology was extensive: 37% received a computed tomography scan, 25% received a magnetic resonance imaging scan, and 10.4% underwent surgery. CONCLUSIONS: Chronic back pain is common, and the level of care-seeking and costs of care among those afflicted are extremely high.
Adult↗
A probabilistic atlas of the human brain: theory and rationale for its development. The International Consortium for Brain Mapping (ICBM).
Explore the source record for details and available documents.
Brain Mapping↗
The human optic nerve: fascicular organisation and connective tissue types along the extra-fascicular matrix.
Fibres in the mammalian optic nerve are arranged into fascicles between which there is an extra-fascicular matrix containing connective tissue, a feature similar to that found in association with fibres in peripheral nerves, but not otherwise found in the CNS. The relationship between these major features of the nerve architecture are not known. We have addressed this question by examining the fascicular organisation of the optic nerve and the distribution of connective tissue and specific collagen types in the human. We have also examined the spatial development of connective tissue in the human nerve to determine when and from where it originates. Fibres are grouped into fascicles at all locations along the nerve, except intracranially, close to the chiasm where this pattern is lost. Relatively large fascicular numbers are found directly behind the eye and in the region of the optic canal, but decline in the mid-orbital segment of the nerve. Connective tissue is present in the extra-fascicular matrix throughout the fasciculated segment, but in many cases it does not fully encircle fascicles. The proportion of matrix occupied by connective tissue is similar along the length of the nerve (approximately 60%). Within the matrix, collagen types I, III, IV, V and VI are present throughout fasciculated regions. Staining for types V and VI appeared relatively weak compared with that for the other types. Although the collagen types in the nerve are similar to those at the lamina cribrosa and in peripheral nerves, they did not appear to be differentially distributed as in regions of the PNS. Connective tissue enters the nerve at a number of wide-spread locations early in development, consistent with the notion that it enters the nerve with the blood supply. It is present within the matrix before it is established at the lamina cribrosa.
Aged↗
Cardiovascular risk factors and alcohol consumption in France and Northern Ireland.
The levels of different lipid, lipoprotein and haemostatic variables were assessed in 615 control subjects of the ECTIM Study, defined by five groups of alcohol consumption: non-drinkers, 0 < or = 15 g/day, 15 < . < or = 36 g/day, 36 < . < or = 66 g/day and > 66 g/day. After adjustment for age, body mass index, cigarette consumption and country, alcohol consumption was associated with an increase in HDL-cholesterol (0.47 +/- 0.02 to 0.59 +/- 0.01 g/l in non-drinkers and > 66 g/day consumers, mean +/- S.E.M., P < 0.0001), apolipoproteins A-I and A-II (1.37 +/- 0.03 to 1.60 +/- 0.03 g/l and 0.32 +/- 0.01 to 0.41 +/- 0.01 g/l, respectively, P < 0.0001), LpA-I, LpA-I:A-II (0.46 +/- 0.01 to 0.50 +/- 0.01 g/l and 0.75 +/- 0.02 to 0.91 +/- 0.02 g/l, respectively, P < 0.001) and PAi-1 activity (134 +/- 11 to 177 +/- 11 U/ml, P < 0.001). Conversely, no increases were found for total and LDL-cholesterol, triglycerides, apolipoproteins B and C-III, LpE:B, LpC-III:B, fibrinogen and factor VII. Hence, among the lipid and haemostatic variables studied, only HDL parameters and PAi-1 activity were increased by alcohol consumption.
Adult↗