Search PubMed⌕ Search

Biomedical subjects

A Lucas

Publications and source records attributed to A Lucas.

At least 163 records · Page 9Linked to original sources
PubMed1996

Early diet of preterm infants and bone mineralization at age five years.

Bone disease with significantly reduced bone mineralization is common in preterm infants, and associated with later linear growth stunting at 18 months of age. Dietary insufficiency of calcium and phosphorus is thought to be the principal aetiological factor. We studied 54 children at mean age 5 years who were born preterm and had participated in a prospective multicentre study of effects of early diet on later growth and development. Diets compared were banked donor breast milk and preterm formula fed as a supplement to mother's own milk. Increasing human milk intake was strongly positively associated with later bone mineral content. Children fed predominantly human milk had greater bone mineral content than children of similar size born at term. These data suggest that the early nutritional environment of the preterm infant could play an important role in determining later skeletal growth and mineralization.

Age Factors↗
PubMed1996

Total energy expenditure in small for gestational age infants.

AIM: To measure total energy expenditure and body composition in small for gestational age (SGA) infants in order to investigate proposed hypermetabolism in such babies. METHODS: A cross sectional study of 52 SGA infants measured at 5 weeks of age was made, using existing data from appropriate for gestational age (AGA) infants as controls. The double labelled water technique was used to assess both total energy expenditure and body composition. RESULTS: Multiple regression analysis showed that expressing energy expenditure per kg fat free mass adjusts for body composition in infants of this age. The relation between total energy expenditure and fat free mass differed between the two groups. CONCLUSION: These data indicate that for a given fat free mass the total energy expenditure of SGA infants is greater than that of AGA infants. Such data should be taken into account when energy requirements for SGA infants are being considered.

Body Composition↗
PubMed1996

Total energy expenditure in small for gestational age infants.

OBJECTIVE: To measure total energy expenditure and body composition in small for gestational age (SGA) infants, to investigate hypermetabolism. METHODS: A cross-sectional study was performed in 52 small for gestational age (SGA) measured at 5 weeks of age, using existing data from appropriate for gestational age (AGA) infants as controls. The doubly-labelled water technique was used to assess both total energy expenditure and body composition in both cohorts of infants. RESULTS: Multiple regression analysis revealed that expressing energy expenditure per kg fat free mass adjusts for body composition in infants of this age. Regression analysis also showed that the relation between total energy expenditure and fat free mass differed between the two groups. CONCLUSION: These data indicate that for a given fat free mass, the total energy expenditure of SGA infants is greater than that of AGA infants. Such data should be taken into account when energy requirements for SGA infants are being considered.

Adipose Tissue↗
PubMed1996

Amelioration of antigen induced arthritis in rabbits treated with a secreted viral serine proteinase inhibitor.

OBJECTIVE: To evaluate the effects of intraarticular administration of SERP-1 protein, a myxoma virus derived antiinflammatory serine protease inhibitor, in an antigen induced arthritis (AIA) model of chronic inflammation. METHODS: AIA was induced in a single joint of 15 rabbits after intraarticular (i.a.) injection of ovalbumin in animals previously immunized to the same agent administered in complete Freund's adjuvant. A 2nd i.a. injection of ovalbumin was given 2 weeks later preceded by 2 daily injections of human transforming growth factor-beta 2. SERP-1 was given by i.a. injection at 2 and 4 weeks after the last i.a. injection of ovalbumin. Three synovial specimens per joint were obtained for synovial histology. Patellar articular cartilage was assessed for collagen integrity and proteoglycan staining. RESULTS: Synovial histology revealed significant diminution in synovial lining cellular hyperplasia, chronic inflammatory infiltration, and cartilage erosion in treated animals, particularly in those receiving 2 i.a. injections of 1 ng of SERP-1. Preservation of articular cartilage was concomitantly noted in treated animals. A dose-response influence on histopathologic change was discernible. CONCLUSION: A viral derived antiinflammatory protein, SERP-1, demonstrates considerable potency in ameliorating chronic inflammation in the AIA model and warrants further investigation as a potential anti-arthritic agent.

Animals↗
PubMed1996

[Preliminary evaluation of the performance of 3D morphometer and spiral scanner in carotid stenoses].

Carotid stenosis evaluation is now possible with 3D Imaging. We prospectively compared the diagnostic value of Spiral CT and 3D Morphometer with conventional intraarterial DSA considered as the gold standard. We studied 19 bifurcations in 10 patients. We evaluated the stenosis following the NASCET guidelines on the DSA, with common carotid injection, on the 3D databases of 3D morphometer and of spiral CT (using MIP display). There was a good correlation between the degree of stenosis calculated with the 3D morphometer and angiography even if severe stenoses were slightly overestimated with the former. For the spiral CT databases, accurate diameters were impossible to obtain in case of huge calcifications. There was no benefit of measuring the surfaces on reoriented axial views in comparison with native axial views and MIP images. With the 3D morphometer, post processing selective visualization of the carotid bifurcations is possible without selective injection. The 3D acquisition with 3D morphometer could be an additional acquisition of a standard DSA. It should replace selective injections and should reduce the side effects of angiography.

Angiography↗
PubMed1996

[Multimodal approach to carotid bifurcation in atherosclerosis].

The cost of treatment of ischemic stroke (second cause of death for elderly patients) is increasing. carotid bifurcation surgery can change the prognosis (as proven by NASCET and ECST studies) for symptomatic patients with over 70% of carotid narrowing. Exploration of the carotid bifurcation is an important step in the diagnosis and must assess the degree of stenosis, the smoothness of the plaque and describe the collateral vessels. Duplex sonography is used to analyze the plaque and to measure the hemodynamic consequences beyond the stenosis. Transcranial Doppler is used to study the hemodynamic consequences at the circle of Willis. 3D TOF MR Angiography visualizes vessels using MIP but with a risk of overestimation of the degree of stenosis. A good morphological study of the circle of Willis can be achieved. With spiral CT, 3D data bases can be acquired with a single injection of contrast medium. Analysis is based on native, reformatted and MIP images. The image quality is generally good, but decreases in the case of huge calcifications. Brain examination can be performed in the same session, looking for rupture of the blood-brain barrier. Angiography remains the gold standard with a high complication rate. It allows excellent analysis from the aortic arch to distal cortical vessels. Isotope studies are only performed in difficult cases (vertebro-basilar lesions, differential diagnosis). Duplex ultrasound is performed first in all protocols. Until recently, angiography was performed before surgery, but the current tendency is to use a less invasive examination (MR angiography or CT angiography) and angiography is then only performed when necessary. A knowledge of the respective advantages of each technique is essential in order to adapt the protocols to each local team.

Angiography, Digital Subtraction↗
PubMed1995

Laser-induced fluorescence: III. Quantitative analysis of atherosclerotic plaque content.

BACKGROUND AND OBJECTIVE: Laser-induced fluorescence (LF) spectroscopic analysis of the chemical composition of atherosclerotic plaque was examined. STUDY DESIGN/MATERIALS AND METHODS: The intima of 18 dog aortas was injected with chemical compounds found in atherosclerotic plaque. Spectra were recorded in air prior to and after injection of collagens I, III and IV, elastin, cholesterol, triglyceride, and beta-nicotinamide adenine dinucleotide (NADH). RESULTS: Significant changes in LF intensity were detected after injection of collagens I and III, cholesterol and elastin in thoracic aorta (P < 0.001), but not with triglyceride or NADH. Minor changes were detected in abdominal aorta. Multiple regression analysis of LF intensity ratios demonstrated a clear correlation with the quantity of injected collagens I (R2 = 0.90-0.99) and III (R2 = 0.84-1.0), cholesterol (R2 = 0.72-0.76), and triglyceride (R2 = 0.68-0.80) in both thoracic and abdominal aorta. The correlation between LF and atherosclerotic plaque composition was confirmed in a rooster model of atherosclerosis where multiple regression analysis predicted the measured aortic cholesterol (R2 = 0.78) and triglyceride content (R2 = 0.96). CONCLUSIONS: (1) Fluorescence spectra recorded from dog aorta were significantly altered by injection of collagens I and III, cholesterol, and elastin. (2) LF may allow quantitative assessment of plaque chemical content.

Analysis of Variance↗
PubMed1995

Parental body composition and infant energy expenditure.

It has been suggested that infants born to overweight parents are at risk of becoming overweight because of reduced total energy expenditure (TEE). We therefore examined the relationship between infant TEE and parental nutritional status as assessed by body mass index (BMI) in a large sample of healthy infants. TEE was measured by the doubly labeled water method in 124 infants at 12 wk of age. Sleeping metabolic rate (SMR) was measured by indirect calorimetry in 70 of these infants. Indexes of physical activity were calculated as TEE/SMR and TEE-SMR. No aspect of infant energy expenditure was found to be related to parental BMI. Moreover, there was no difference between TEE of two subsets of infants born to parents with high and low BMIs. We therefore find no evidence for parental body composition being associated with reduced infant energy expenditure at 12 wk of age.

Adult↗
PubMed1995

Assessing the effectiveness of X-ray contrast media for abdominal computed tomographic examinations: comparison of four low-osmolality agents.

The objective of this investigation was to assess the effectiveness of four iodinated X-ray contrast media for abdominal computed tomographic (CT) examinations. Fifty-three patients were prospectively randomized to receive iohexol 300 mgI/ml (100 ml, n = 17), ioversol 320 mgI/ml (100 ml, n = 13), iopromide 300 mgI/ml (75 ml, n = 12), or iopentol 300 mgI/ml (100 ml, n = 11) to perform a dynamic contrast-enhanced abdominal CT. Image-enhancement profiles for the liver, aorta, and vena cava were studied. The maximum liver enhancement, the time to maximum liver enhancement, and the area under the hepatic enhancement-time curve (AUC) were determined for each examination. Liver-enhancement profile showed significant differences between the four contrast agents, with lower values for iopromide towards the final part of the CT examination (P < 0.05). Hepatic peak values were attained earlier for iopromide, although these were lower than those produced by any other of the agents evaluated in this study. Iopentol produced fast and intense hepatic peaks. Consequently, high AUC values were obtained with iopentol, low values were obtained with iopromide (P < 0.05), although this can be explained by the lower amount of contrast medium contained in the commercial vial and administered to the patient (75 ml vs 100 ml). When normalized to a 100 ml dose, the AUC value for iopromide becomes even higher than the average of the other three agents (P = 0.05). Ioversol, although available and administered as a more concentrated solution (320 mg/ml), was comparable to the less concentrated iohexol and iopentol (300 mgI/ml).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Maternal smoking and blood pressure in 7.5 to 8 year old offspring.

Reduced fetal growth in babies born preterm may be associated with reduced later blood pressure, but in children born at term, higher blood pressure. It was hypothesised, therefore, that maternal smoking in pregnancy, associated with reduced fetal growth, programmes later blood pressure differentially according to length of gestation. Six hundred and eighteen children born preterm and now aged 7.5 to 8 years were studied prospectively. Systolic blood pressure in children from smoking compared with non-smoking mothers was significantly lower in those born before 33 weeks' gestation and significantly higher in those born at 33 or more weeks. Within the range 0-40 cigarettes per day until delivery (after adjusting for potentially confounding factors, including social class and current weight) each 10 was associated with a 1.5 mm Hg fall and 2.9 mm Hg rise in pressure for children born below or above 33 weeks' gestation respectively. Similar though smaller differences were seen in diastolic pressure. These data support our hypothesis that later effects of insults impairing fetal growth are gestation dependent, and provide the first evidence that maternal smoking may have long term consequences for blood pressure in children.

Blood Pressure↗
PubMed1995

Fine-needle aspiration cytology of benign nodular thyroid disease. Value of re-aspiration.

Fine-needle aspiration cytology (FNAC) has become a widespread procedure for the study of thyroid nodules (TN). Some authors recommend the practice of repeated punctures for their follow-up. This study was done to determine the usefulness of repeated FNAC in patients with benign nodular thyroid disease. We have studied 251 fine-needle re-aspirations performed on 116 females aged 45.6 +/- 14 years with benign nodular thyroid disease. The time elapsed between each consecutive FNAC was 1 year. No patients presented any changes in the size or consistency of their nodular goiters during this period; all FNACs were carried out by the same physician in the same thyroid area according to the Löwhagen technique, with a minimum of two or three aspirations of each nodule, and processed in the same way and valued by the same cytologist without any knowledge of previous cytological diagnoses. These were done using strictly classical criteria (Löwhagen). One hundred and five out of 116 patients (90.51%) with two consecutive FNACs (210) showed identical cytological diagnoses in the two specimens studied. The remaining 11 patients (9.48%) with two FNACs were diagnosed with colloid goiter and cyst alternately. Fifteen out of 19 patients (78.94%) with three FNACs showed identical cytological diagnoses in the three samples and the rest (21%) also demonstrated alternate diagnoses of colloid goiter and cyst. Our results show that the routine performance of repeated FNAC in the follow-up of females with benign nodular thyroid disease, without any clinical changes, is of limited usefulness.

Adult↗
PubMed1995

Age as a determinant of glomerular filtration rate in non-insulin-dependent diabetes mellitus.

BACKGROUND: The level of glomerular filtration rate (GFR) and its determinants in non-insulin-dependent diabetes mellitus (NIDDM) are currently controversial. DESIGN OF THE STUDY: We measured GFR and effective renal plasma flow (ERPF) in 121 consecutive NIDDM without evidence of overt diabetic nephropathy. Age varied from 28 to 70 years, 61.2% were women and known duration of NIDDM was 0-37 years. Hypertension was detected in 36.4% of patients and 47.8% had microalbuminuria. RESULTS: An inverse correlation was found between GFR and age, but not with known duration of NIDDM: It was a weak correlation (r = -0.41) but statistically significant (P < 0.001). The other variables considered were not significant by multiple stepwise regression analysis, but patients with lower GFR tended to have diabetic retinopathy more frequently. GFR was lower in hypertensive compared to normotensive patients (123 +/- 28.4 versus 136 +/- 32.5 ml/min/1.73 m2; P < 0.05), but was not different between patients with normal and elevated albumin excretion rate. ERPF also had an inverse correlation with age (r = -0.45, P < 0.001). CONCLUSION: We conclude that (i) age should be considered as a confounding variable when evaluating GFR in patients with NIDDM, and (ii) the age-dependent decline in GFR may mask hyperfiltration in the early stages of diabetic nephropathy in NIDDM:

Adult↗