Search PubMed⌕ Search

Biomedical subjects

J Hopkinson

Publications and source records attributed to J Hopkinson.

At least 19 recordsLinked to original sources

Is late diagnosis of lung cancer inevitable? Interview study of patients' recollections of symptoms before diagnosis.

BACKGROUND: A study was undertaken to explore the pathway to diagnosis among a group of patients recently diagnosed with lung cancer. METHODS: A directed interview study triangulating patients' accounts with hospital and GP records was performed with 22 men and women recently diagnosed with lung cancer at two cancer centres in the south and north of England. The main outcome measures were the symptoms leading up to a diagnosis of lung cancer and patient and GP responses before diagnosis. RESULTS: Patients recalled having new symptoms for many months, typically over the year before their diagnosis, irrespective of their disease stage once diagnosed. Chest symptoms (cough, breathing changes, and pain in the chest) were common, as were systemic symptoms (fatigue/lethargy, weight loss and eating changes). Although symptoms were reported as being marked changes in health, these were not in the main (with the exception of haemoptysis) interpreted as serious by patients at the time and not acted on. Once the trigger for action occurred (the event that took patients to their GP or elsewhere in the healthcare system), events were relatively speedy and were faster for patients who presented via their GP than via other routes. Patients' beliefs about health changes that may indicate lung cancer appeared to have played a part in delay in diagnosis. CONCLUSION: Further investigation of the factors influencing the timing of diagnosis in lung cancer is warranted since it appears that patients did not readily attend GP surgeries with symptoms. Insight into patients' perspectives on their experience before diagnosis may help medical carers to recognise patients with lung cancer more easily so that they can refer them for diagnosis and treatment. Encouragement to present early with signs of lung cancer should be considered alongside other efforts to speed up diagnosis and treatment.

Adult↗

Randomized clinical trial of the effects of immediate enteral nutrition on metabolic responses to major colorectal surgery in an enhanced recovery protocol.

BACKGROUND: The effects of immediate postoperative enteral nutrition on postoperative nitrogen balance and insulin resistance were studied in patients subjected to an enhanced-recovery protocol. METHODS: Eighteen patients undergoing major colorectal surgery in an enhanced-recovery protocol were randomized to immediate postoperative enteral feeding for 4 days with either complete or hypocaloric nutrition. Nitrogen balance and changes in glucose kinetics, substrate utilization (indirect calorimetry) and insulin sensitivity (hyperinsulinaemic-euglycaemic clamp) were measured. Values are mean(s.e.m.). RESULTS: Mean postoperative urinary nitrogen losses were low (10.7(1.0) versus 10.5(0.7) g per day for complete versus hypocaloric nutrition) and insulin resistance was insignificant (-20(7) versus -27(11) per cent), with no difference between groups. Complete enteral feeding was given without hyperglycaemia (blood glucose concentration 5.8(0.4) versus 5.0(0.4) mmol/l) and resulted in nitrogen balance (+0.1(0.8) versus -12.6(0.6) g nitrogen per day; P < 0.001). CONCLUSION: This enhanced-recovery protocol was associated with minimal postoperative insulin resistance and nitrogen losses after surgery. Immediate postoperative enteral nutrition was provided without hyperglycaemia and resulted in nitrogen balance.

Blood Glucose↗

LiV2O4: frustration induced heavy fermion metal.

We propose a two-stage spin-quenching scenario for the unusual heavy fermion state realized in the mixed valent metal LiV2O4. In this theory, local valence fluctuations are responsible for the formation of partially quenched, spin-1 / 2 moments below room temperature. Frustration of the intersite spin couplings then drives the system to produce the heavy Fermi liquid seen at low temperatures. The anomalous resistivity and the sign change of the Hall constant can be understood naturally within this model, which also predicts a unique symmetry for the heavy quasiparticle bands that may be observed in de Haas-van Alphen experiments.

Journal Article↗

Fat mass in infants and toddlers: comparability of total body water, total body potassium, total body electrical conductivity, and dual-energy X-ray absorptiometry.

BACKGROUND: Accurate assessment of body composition in infants and children is fundamental to understanding normal growth and development. Validation of methods applicable to pediatric populations is needed. In the absence of a gold standard, this study was conducted to compare methods using total body water, total body potassium, total body electrical conductivity, and dual-energy x-ray absorptiometry measurements for the estimation of body fat mass in infants and toddlers. METHODS: Repeated body composition measurements were performed on 76 healthy term infants at 0.5, 3, 6, 9, 12, 18, and 24 months of age. Total body water was determined by deuterium dilution and converted to fat-free mass. Total body electrical conductivity was used to measure fat mass. Total body potassium was estimated by whole-body counting and converted to fat-free mass. Dual-energy x-ray absorptiometry was used to estimate fat mass at 0.5, 12, and 24 months only. Data were analyzed by repeated measures analysis of variance, followed by Bonferroni multiple comparisons at 5%. RESULTS: Significant differences among methods were encountered at each age (p = 0.001-0.05). The rank order of the methods and the magnitude of the method differences were a function of age, not of gender or infant feeding mode. Wide limits of agreement imply that the methods are not interchangeable for group or individual measurements. CONCLUSIONS: Methods using total body water, total body potassium, total body electrical conductivity, and dual-energy x-ray absorptiometry to estimate body fat mass in infants and toddlers are not interchangeable and require further development and validation.

Absorptiometry, Photon↗

Health promotion in the Hutterite community and the ethnocentricity of empowerment.

Empowerment, one of the cornerstones of health promotion, has been influenced by the transformative and emancipatory perspectives of the revolutionary educator Paulo Freire and critical social theory. The empowerment process is conceived as one of liberation from oppression, powerlessness, and ignorance, and at its core are notions of grassroots activism and rejection of the status quo. This paper critically examines the challenges faced by health-promotion practitioners and researchers who seek to work in an empowering way with a culturally distinct group, the Hutterites. The Hutterian world-view, which values (a) communalism, (b) respect for hierarchical decision-making, and (c) strict adherence to a traditional code of conduct, values, and beliefs, provides an opportunity to critique the ethnocentricity of the empowerment process.

Anthropology, Cultural↗

Alignment of multi-segmented anatomical features from radiation therapy images by using least square fitting.

A least square fitting algorithm for alignment of multi-open-curved segments and point pairs of anatomical features obtained from both portal images and simulation radiographs has been developed for patient position verification in radiation therapy. A coordinate system associated with each curved segment pair is constructed so that the discrepancies of each segment pair can be obtained easily. The algorithm allows users to select not only multiple curve pairs but also individual point pairs on the important anatomic landmarks. The misregistration is measured by the sum of the position deviation of individual point pairs and ordinate discrepancies of all segment pairs from their corresponding coordinate systems. A mathematical minimization method is applied to seek an optimal transformation for matching of all segment and/or point pairs involved. The reliability of the algorithm has been tested with both phantom and clinical images. The test results indicate that the typical errors are less than 1 mm and 1 degrees in translation and rotation, respectively.

Algorithms↗

Increased translation as a result of elevated initation factor activity after administration of 3-methylcholanthrene.

Protein synthesis initiation factors present in a crude 0.5 M KCL microsomal wash fraction were isolated from the livers of immature rats that had been injected either 2 or 17 hours earlier with the plycyclic hydrocarbon, 3-methylcholanthrene (3MC), and then were tested for their ability to stimulate natural mRNA-directed protein synthesis in vitro. After purification of the initiation factors by means of ammonium sulfate fractionation, and DEAE-cellulose and Sephadex G-200 chromatography, M2A and M2B, but not M3 or M1, from the livers of 3MC-pretreated rats were more active than were similarly-prepared control factors in their ability to initiate the synthesis of rabbit globin polypeptides in a highly fractionated cell-free protein synthesizing system derived from rabbit reticulocytes. The greater activity of the M2A and M2B preparations from drug-treated rat liver did not appear to be due to differences in the composition of initiation factor protein extracted from the livers of control or experimental rats and occurred very early after administration of 3MC, i.e., 2 hr. The role of the protein synthesis initiation factors in the altered rates of protein synthesis which accompany cytodifferentiation and growth is discussed.

Ammonium Sulfate↗