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C Tomlinson

Publications and source records attributed to C Tomlinson.

At least 19 recordsLinked to original sources
PubMed2006

Longitudinal changes in bone health as assessed by the speed of sound in very low birth weight preterm infants.

OBJECTIVE: To assess longitudinal changes in speed of sound (SOS) in very low birth weight (VLBW) infants and investigate the relationship with markers of osteopathy of prematurity (OP) and clinical illness. STUDY DESIGN: Twenty-five infants were recruited. Eighteen infants, median gestation 27 weeks (range 24-32), median birth weight 957 g (range 625-1500 g), had serial scans. SOS was measured at both tibiae weekly until 35 to 37 weeks corrected gestational age (CGA). RESULTS: Initial median SOS standard deviation score (SDS) (Z) score was -0.07 (range-1.3-1.3). SOS correlated with gestation (r, 0.8, P<.005), and birth weight (r, 0.67, P<.005.) SOS fell from a median of 2923 m/s (2672-3107) at birth to 2802 m/s (2502-2991) at 35 to 37 weeks CGA (P<.05). This fall was greater in the 24- to 27-week gestation cohort with a median reduction of 2.2 SDS (1.6, 4.0) compared with 1.3 SDS (0.8-2.2) in those>28 weeks (P<.05). There was a negative correlation between SOS, at the end of the study, peak serum alkaline phosphatase (ALP) (r, 0.6, P<.05), CRIB (Clinical Risk Index for Babies)/CRIB II scores (both r, 0.6, P<.05), and duration of total parenteral nutrition (TPN) (r, 0.58, P<.05.) CONCLUSIONS: Although tibial SOS was within the expected range at birth, there was a subsequent failure to gain SOS, and this was most marked in infants of a lower gestation.

Alkaline Phosphatase↗
PubMed2005

Quantitative ultrasound assessment of bone in preterm and term neonates.

There is a need to explore novel methods of assessing bone health in sick preterm infants. This study of the speed of sound in the long bones of newborn term and preterm infants shows that, in this population, this technique is not site specific and has a high degree of interobserver and intraobserver precision. The speed of sound in newborn infants is primarily dependent on gestation rather than birth weight.

Birth Weight↗
PubMed2004

G209A mutant alpha synuclein expression specifically enhances dopamine induced oxidative damage.

Alpha synuclein protein may play an important role in familial and sporadic Parkinson's disease pathology. We have induced G209A mutant or wild-type alpha-synuclein expression in stable HEK293 cell models to determine if this influences markers of oxidative stress and damage under normal conditions or in the presence of dopamine or paraquat. Induced wild-type or mutant alpha-synuclein expression alone had no effect upon levels of oxidative stress or damage, as measured by glutathione levels or aconitase activity. Both wild-type and mutant alpha-synuclein expression decreased the oxidative damage induced by paraquat, although the protection was less marked with mutant alpha-synuclein expression. This suggests that alpha-synuclein expression may either have anti-oxidant properties or may upregulate cellular antioxidant levels, a function that was diminished by the G209A mutation. However, mutant but not wild-type alpha-synuclein expression specifically enhanced dopamine associated oxidative damage. Non-expressing cells treated with reserpine to inhibit the vesicular monoamine compartmentalisation produced similar results. However, consistent with the hypothesis that mutant alpha-synuclein disrupts vesicular dopamine compartmentalization, this effect was diminished in cells expressing mutant alpha-synuclein. This may result in increased dopamine metabolism and cause selective oxidative damage to dopaminergic cells.

Aconitate Hydratase↗
PubMed2004

Testosterone measurements in early infancy.

Circulating testosterone concentrations in infants measured by a direct chemiluminescent immunoassay (Bayer ADVIA Centaur) were compared with those measured by a traditional radioimmunoassay using solvent extraction. The results confirm that neonatal circulating testosterone concentrations are method dependent, and each laboratory should establish method related reference ranges especially if using a direct commercial immunoassay. The results indicate that the Bayer ADVIA Centaur procedure can be used reliably in neonates. Expected values for male and female infants < 10 days old were 2.5-11.1 (n = 36) and 1.7-5.6 (n = 36) nmol/l respectively. For older neonates (10-50 days) the ranges were 0.2-17.2 (n = 42) and 0.1-1.5 (n = 7) nmol/l respectively.

Age Factors↗
PubMed2000

Regional mucociliary clearance in patients with cystic fibrosis.

This paper reports on a large retrospective analysis of mucociliary clearance (MCC) studies in a group of 59 patients with cystic fibrosis (CF) and 17 age-matched healthy subjects. As many of the CF patients were studied on multiple occasions, a total of 184 patient studies are presented. MCC was measured using a radioaerosol and gamma camera technique. In addition to whole lung clearance, MCC was measured from the central, intermediate, peripheral, basal, mid and apical regions of the lung. MCC was markedly decreased in the CF patient group. Not only was whole lung clearance (14.2 +/- 1.4% vs. 28.0 +/- 3.7%) impaired, but also clearance from the central (19.1 +/- 1.9% vs. 35.6 +/- 4.3%), intermediate (10.7 +/- 1.6% vs. 25.5 +/- 3.7%), apical (12.4 +/- 2.6% vs. 31.6 +/- 4.6%) and mid (14.0 +/- 1.9% vs. 30.4 +/- 4.0%) regions. Attempts were made to identify factors that may have influenced MCC in both the normal subjects and CF patients. Age, gender, body mass index, patient genotype, penetration index, spontaneous cough, and various lung function parameters were entered into a stepwise multiple regression model, but none of the factors proved to be statistically important in determining MCC. Both intrasubject repeatability and intersubject variability estimates are presented for the patients and normal subjects that had multiple studies. The values were found to be remarkably similar for both CF patients and normal subjects and for both intra- and intersubject repeatability. With marked deviation from normal ranges and good repeatability, the measurement of MCC in CF patients would seem to be a valuable outcome measure for clinical trials involving new pharmaceuticals and physical therapy designed to improve removal of secretions from the airways.

Adolescent↗
PubMed1996

Sandor Rado and Adolf Meyer: a nodal point in American psychiatry and psychoanalysis.

Previously uncited archival material, principally letters between Adolf Meyer and Sandor Rado, is used to document the importance of a relationship between two influential figures in american psychiatry and psychoanalysis at a fateful moment in the evolution of both. Although Meyer and Rado have each fallen into relative neglect, their interaction not only was a crucial part of the schisms in American analysis in the 1930s and 1940s, but represented an important juncture in the history of the relationship between medicine, academic psychiatry and psychoanalysis in North America. Meyer's powerful influence was thus an essential component of Rado's attempts to rewrite psychoanalytic theory and terminology wholesale. Moreover, Rado specifically integrated the results of a radically integrationist agenda he had consolidated in his contact with Meyer into the organisation and educational programme of the psychoanalytic institute he founded at Columbia University in the early 1940s.

History, 19th Century↗
PubMed1993

Haemodialysis recirculation detected by the three-sample method is an artefact.

The efficiency of haemodialysis may be limited by recirculation of blood between venous and arterial needles. Recirculation can be detected directly using a saline dilution method but is most commonly calculated from the urea concentrations of simultaneous samples from venous and arterial lines and a peripheral vein (three-sample method). The methods detect markedly different rates of recirculation in similar study populations. To investigate the possibility that the methods detect different phenomena, we performed both tests on 16 haemodialysis patients at various extracorporeal blood flow rates (Qb). The saline dilution method showed no recirculation in any of the patients, whereas the three-sample method indicated recirculation in all patients. The three-sample method indicated a mean recirculation fraction of 12.5% (SD 6.1) and was not influenced by changing Qb, suggesting that it was not detecting fistula recirculation. The three-sample method detects a solute concentration difference between arterial blood and peripheral blood during dialysis. There appears to be a disequilibrium between a central pool, represented by the arterial sample, and a poorly perfused peripheral pool, relatively isolated from the dialysis process, represented by the peripheral venous sample. The three-sample method for detecting recirculation should be abandoned.

Arteries↗
PubMed1992

G. C. Lichtenberg: dreams, jokes, and the unconscious in eighteenth-century Germany.

The German physicist and writer Lichtenberg (1742-1799) was well known during the nineteenth century as a humorist, thinker, and psychologist. He was also a favorite author of Freud, who read him beginning in his teens, quoted him frequently, and called him a "remarkable psychologist." Despite this, he has been ignored by psychoanalysts and historians of psychiatry alike, and most of his writing is still unavailable in English. An introduction to Lichtenberg as a psychologist is provided, stressing material dealing with dream analysis, association theory, and drives. Relevant excerpts are translated into English. Lichtenberg is shown to have insisted upon the need for a systematic and rationalistic study of dreams, to have analyzed individual dreams (describing them as dramatized representations of thoughts, associations, and even conflicts from his own waking life), and to have emphasized the functional link between dreams and daydreams. His remarks on drives and commentary on eighteenth-century association theory represent a significant practical application, and thus refinement, of Enlightenment rationalistic psychology. These achievements are assessed in light of Freud's early fascination with him; it is argued that Lichtenberg is an example of the relevance of the historical and cultural background of psychoanalysis to clinical practice.

Association↗
PubMed1991

Papillary cancer in a patient treated with radioiodine for Graves' hyperthyroidism. Case report and a review of the risk.

A small encapsulated papillary thyroid cancer was found in a patient who had received I-131 therapy for Graves' disease 31 months previously. The relationship of Graves' hyperthyroidism and thyroid cancer is discussed, as well as the possible role of I-131 as a cause of the cancer. The published data do not support I-131 as an etiology. The patient is clinically well and cured of both hyperthyroidism and the cancer.

Adult↗
PubMedDate not supplied

Canadian consensus recommendations for the measurement and reporting of diastolic dysfunction by echocardiography: from the Investigators of Consensus on Diastolic Dysfunction by Echocardiography.

Abnormalities of diastolic filling are increasingly recognized as a cause of symptoms and predictors of outcome in patients with most forms of heart disease. Noninvasive assessment of diastolic filling is possible in almost all patients, but accurate evaluation must relate echocardiographic Doppler measurements to the complex physiologic and hemodynamic factors responsible for normal and abnormal filling. This evaluation has been facilitated by recent correlation of Doppler measurement of mitral and pulmonary venous inflow with hemodynamic studies. These studies have confirmed that when a careful, integrated approach is taken, Doppler flow patterns can document a progressive pattern of abnormality in many conditions. Impaired left ventricular (LV) relaxation is seen early and is recognized by a decrease in early transmitral LV filling and an increased proportion of filling during atrial contraction. As abnormalities progress, increasing LV chamber stiffness and elevated left atrial pressure lead to a "pseudonormal" filling pattern that previously has caused considerable confusion. This can be unmasked by careful evaluation of pulmonary venous inflow and the use of the Valsalva maneuver. When marked diastolic abnormalities are present, LV filling has restrictive features characterized by rapid early filling, a very stiff left ventricle with high filling pressures, and a poor prognosis. Routine measurement of indexes of diastolic filling have been hampered by uncertainty as to what should be measured, what techniques should be used, definition of normal values, and a clear method of reporting findings. This report represents the efforts of a Canadian consensus group to define a national standard for the performance and reporting of echocardiographic Doppler studies of diastolic filling.

Aged↗