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M Elia

Publications and source records attributed to M Elia.

At least 109 records · Page 6Linked to original sources
PubMed1998

Glutamine metabolism in the gastrointestinal tract of the rat assess by the relative activities of glutaminase (EC 3.5.1.2) and glutamine synthetase (EC 6.3.1.2).

The activities of the two key enzyme involved in glutamine metabolism, glutaminase (EC 3.5.1.2) and glutamine synthetase (EC 6.3.1.2), have been measured in the various tissues of the gastrointestinal (GI) tract of the rat, from the mouth to the rectum. Glutaminase activity was particularly high in the mucosa of the small intestine, where its activity accounted for more than 80% of the total activity of the GI tract. In contrast, the mouth and oesophagus had very low activities, accounting for less than 2% of the total. Glutamine synthetase was mainly confined to the lower part of the stomach, which accounted for almost 90% of the total activity of the GI tract. Activity in the small intestine was very low, accounting for less than 2% of the total, and similarly low levels were found in the mouth and oesophagus. The data provide the most complete information on the distribution of these enzymes in the GI tract of the rat and suggest: (a) that the mucosa of the small intestine has the highest capacity for glutamine breakdown but the lowest capacity for its synthesis, and so requires an external source of this amino acid; (b) that there is little potential for glutamine synthesis or breakdown in the mouth and oesophagus: and (c) that the lower stomach has a substantial capacity to synthesize glutamine, in contrast to the rest of the GI tract. The results of the investigation are relevant to sites of glutamine metabolism in therapeutic studies involving glutamine administration discussed with reference to reports of the effects of glutamine administration on GI tract injury.

Animals↗
PubMed1998

Potential errors in the application of mixture theory to multifrequency bioelectrical impedance analysis.

Potential errors in the application of mixture theory to the analysis of multiple-frequency bioelectrical impedance data for the determination of body fluid volumes are assessed. Potential sources of error include: conductive length; tissue fluid resistivity; body density; weight and technical errors of measurement. Inclusion of inaccurate estimates of body density and weight introduce errors of typically < +/- 3% but incorrect assumptions regarding conductive length or fluid resistivities may each incur errors of up to 20%.

Adult↗
PubMed1998

Sources of error in bioimpedance spectroscopy.

Two different makes of bioimpedance spectrometer (UniQuest-SEAC SFB-3 and Xitron 4000B) were used for a series of measurements on volunteers and patients in intensive care. Although each machine was accurate over the frequency range 5 to 500 kHz when bench tested on model resistor-capacitor circuits, significant differences in their recorded impedance parameters appeared when used in vivo, especially on intensive care patients. A series of laboratory tests was performed on each machine simulating the situation in vivo to identify possible reasons for these differences. Whilst stray capacitance in the environment was identified as the major contributor to variability in high-frequency performance, interaction between electrode impedance and lead positioning was also a factor. The observed phase shift with frequency or time delay (Td) used in the Xitron modeling software appears to be the result of a time constant caused by stray capacitance and so is unlikely to have any biological meaning. Significant differences in the in vivo numerical values produced by bioimpedance spectrometers may be attributed to instrument design, data processing and, in particular, the clinical environment.

Adult↗
PubMed1998

Energy expenditure and net substrate utilization in men ingesting usual and high amounts of nonstarch polysaccharide.

BACKGROUND: Diets intrinsically high in nonstarch polysaccharides (NSPs) are frequently advised for body weight regulation and health, but the consequences for energy expenditure and fuel selection are undetermined. OBJECTIVE: We determined whether energy expenditure and fuel selection differ when men consume a diet intrinsically higher in NSP than a usual mixed diet. DESIGN: A randomized crossover design was used in which 12 healthy men were fed a maintenance diet for approximately 3 wk in a metabolic suite. By judicial choice of food exchanges, the usual- and high-NSP diets were similar in protein, fat, and carbohydrate contents. Twenty-four-hour, indirect, open-circuit calorimetry was performed, including measurements of total hydrogen gas and methane. Participants were weight stable (within 2 kg for 3 wk), entered an 11-m3 calorimetry chamber for 36 h with measurements taken in the last 24 h, and underwent a strictly controlled program of moderate physical activity (1.3 x basal metabolic rate). RESULTS: The mean total 24-h energy expenditure and percentages from protein, fat, and carbohydrate metabolism were 10 MJ/d and 16%, 35%, and 48%, respectively. Differences (mean+/-SEM) between the 2 diets were only -0.005+/-0.130 MJ/d, -0.3+/-1.3%, -0.2+/-2.0%, and 0.6+/-2.2%, respectively, and were nonsignificant (P> 0.2). CONCLUSIONS: There was no thermogenic response to the high-NSP diet, which would be advantageous for body weight control, and no short-term influence on body composition, as may be judged from a lack of change in protein, fat, or carbohydrate metabolism.

Adult↗
PubMed1998

Effect of dietary manipulation on substrate flux and energy balance in obese women taking the appetite suppressant dexfenfluramine.

BACKGROUND: Studies in lean men show poor regulation of energy (EB) and fat balance (FB) during manipulation of dietary ratios of fat to carbohydrate. High-fat (HF), high-energy diets cause hyperphagia and a positive EB and FB. OBJECTIVE: The protocol was designed to measure substrate flux and EB in obese women taking dexfenfluramine (DF) or placebo (PL) during an HF (50% of energy) or low-fat (25% of energy; LF) diet. We hypothesized that alterations in dietary fat would not be regulated and would lead to a positive EB and FB. DESIGN: The study was double-blind, randomized, and placebo-controlled, with 4 treatments (LF/DF, HF/DF, LF/PL, and HF/PL) and a crossover. Five days of continuous, whole-body calorimetry measurements were made in 6 subjects after 8 d of home DF/PL treatment. Macronutrient balance and EB were measured within the chamber as the cumulative difference between ad libitum intake and oxidation. RESULTS: The HF diet increased energy (HF, 10.50 MJ/d; LF, 8.13 MJ/d; P < 0.0001) and fat intakes (HF, 5.34 MJ/d; LF, 2.06 MJ/d; P < 0.0001), leading to a positive EB (delta = 2.37 MJ/d) and FB (delta = 2.31 MJ/d). DF reduced energy (DF, 8.96 MJ/d; PL, 9.66 MJ/d; P < 0.01) and macronutrient intakes, but did not increase energy expenditure (delta = -0.31 MJ/d; P < 0.01), or 24-h fat oxidation (delta = 0.03 MJ/d; P = 0.46). CONCLUSIONS: EB and FB are poorly regulated with HF, energy-dense diets in obese women, which leads to fat deposition and weight gain.

Appetite Depressants↗
PubMed1998

Metabolizable energy of high non-starch polysaccharide-maintenance and weight-reducing diets in men: experimental appraisal of assessment systems.

We have examined the reliability of several food energy assessment systems for healthy men. The predictions of metabolizable energies were compared with determinations made in energy balance studies with three maintenance diets (12 MJ/d); one of the diets was moderate in non-starch polysaccharide (NSP; 2.1% of gross energy) and two were higher in NSP (3.5-4.6% of gross energy). A fourth diet was a submaintenance (6 MJ/d) high NSP (7% gross energy) diet. Discrepancies between the different food energy assessment systems and the determined metabolizable energy values ranged between 0 and 15%. With the maintenance diets, the Atwater specific factor system had errors generally within 6% of the determined value and a limit of agreement (bias +2SD) for diets of 10%. This accuracy compares with errors of 2% for both the originally published assessment of this system and a more recent general formula; both systems were without bias with increasing NSP content of the diets but the latter had limits of agreement within 3%. In contrast, the Atwater general, the European general and a recent FDA general formula showed increasing bias with increasing NSP intake. All of the general energy assessment systems overpredicted metabolizable energy from the high NSP submaintenance diet, which shows that even the least biased and most reliable energy assessment system that we identified applies to maintenance diets only; thus a correction has to be made for submaintenance diets.

Adult↗
PubMed1998

Myoclonic absence-like seizures and chromosome abnormality syndromes.

PURPOSE: We explored the relationship between myoclonic absence seizures (MAS) and underlying chromosome disorders. METHODS: Among 14 patients with MAS observed in three centers, 5 had typical cryptogenic myoclonic absence epilepsy (MAE), 2 had MAS associated with other seizure types (1 with signs of a neuronal migration abnormality and 1 with signs of a metabolic disorder), and 7 had MAS, with or without other seizure types, complicating a chromosome abnormality syndrome-2 with trisomy 12p, 4 with Angelman syndrome, and 1 with inv dup (15). RESULTS: In the 7 patients with chromosomopathy, MAS appeared at a mean age of 2.9 years (range 4 months to 6 years 6 months), had a duration of 4-20 s, and were accompanied by reduced awareness and rhythmic myoclonic jerks involving proximal limb muscles. Ictal EEG showed 2- to 3-Hz generalized spike-and-wave discharges. CONCLUSIONS: In these patients, MAS differed slightly from those of typical MAE: age of onset was earlier, absences were of shorter duration, and no clear increase in muscular tone was noted. Abnormal expression of genes codifying for the subfamily of K+ channels and for gamma-aminobutyric acid-3 subunit receptors (GABRB3), both located in the chromosome segments involved in the chromosomopathies presented by our patients, could be responsible for the same generalized seizure type. Chromosome analysis should be performed in patients with mental retardation and MAS, especially when the ictal pattern does not completely overlap that observed in MAE.

Adult↗
PubMed1997

A new family with periventricular nodular heterotopia and peculiar dysmorphic features. A probable X-linked dominant trait.

OBJECTIVE: To describe 3 sisters with brain periventricular heterotopia and peculiar dysmorphic features as a probable X-linked dominant trait. DESIGN: Clinical, laboratory, neurophysiological, and brain imaging data were studied. SETTING: Research institute for mental retardation. PATIENTS: The 3 sisters had mental retardation, drug-resistant epilepsy, gray matter heterotopia, and peculiar malformations (low nasal bridge, upslanting palpebral fissures, palpebral edema, attached hypoplastic earlobes, thickened calvaria, rectal fibrovascular polyps, urinary tract anomalies, and increased foot length). The patients were 35, 30, and 25 years old and belonged to a sibship of 6, born of nonconsanguineous healthy parents. CONCLUSION: The 3 patients constitute a well-defined clinical entity not previously described of a probable X-linked dominant nature.

Adult↗
PubMed1997

Total energy expenditure in patients with small-cell lung cancer: results of a validated study using the bicarbonate-urea method.

The bicarbonate-urea method for measuring CO2 production was applied to eight free-living patients (mean age, 68 +/- 10 years; mean weight, 69 +/- 10 kg; mean height, 1.65 +/- 0.10 m) with unresectable small-cell lung cancer for a period of 1 day (n = 5) or 2 days (n = 3). The basal metabolic rate (BMR) was measured in all subjects. The technique was first validated against whole-body indirect calorimetry over an additional 24-hour period in five of these subjects. The bicarbonate-urea method predicted net CO2 production to be 102.1% +/- 3.4% of that measured by whole-body indirect calorimetry, and energy expenditure, 101.5% +/- 3.8% of the measured calorimeter value (8.1 +/- 1.6 MJ/d). The 24-hour recovery of label in CO2 excreted by the body was 95.6% +/- 0.5%. In free-living conditions, the bicarbonate-urea method predicted energy expenditure to be 9.0 +/- 2.6 MJ/d. BMR was elevated by a mean of 6% (P < .05) compared with the Schofield standards. The physical activity level ([PAL] the ratio of total energy expenditure [TEE] to BMR) was variable (1.15 to 1.87), but the mean value was only 1.36 +/- 0.22, considerably less than that of moderately active healthy subjects with estimated PAL values of 1.55 (P < .05) to 1.65 (P < .01) and the mean results obtained by doubly labeled water (previous studies) in healthy age- and sex-matched subjects. This is the first time a tracer method for measuring CO2 production and energy expenditure has been validated against whole-body 24-hour indirect calorimetry in patients with lung cancer or a systemic inflammatory reaction. The agreement between the two methods is similar to that observed in normal subjects. This is also the first time a tracer method has been used to measure energy expenditure in free-living patients with lung cancer. The results suggest that TEE and the energy requirements necessary to maintain energy balance were not increased despite basal hypermetabolism, because of the associated decrease in physical activity.

Adult↗
PubMed1997

Multiple frequency bioimpedance: a bed-side technique for assessment of fluid shift patterns in a patient with severe dehydration.

This report describes the use of multiple frequency bioimpedance analysis (MFBIA) to monitor fluid changes in a patient who developed severe dehydration and recovered. Initially, the patient weighed 53.2 kg, his total body water (TBW; D(2)0 dilution) was 33.5 L, his extracellular water (ECW; Br dilution) was 19.5 L, and hydration of the fat-free mass (FFM; dual-energy X-ray absorptiometry) was normal (73%). The resistances at infinite and 0 frequency were R(inf) = 454 and R(0) = 580 ohm respectively, which predicted TBW = 33.1 L and ECW = 16.6 L. On day 7, when the weight loss was 7.2 kg, FFM had decreased by 7.4 kg, and R(inf) and R(0) had increased to 662 and 902 ohm respectively, predicting decreases of 5.8 L in TBW and 3.7 L in ECW. On recovery (day 14), all parameters had returned to baseline values. This study encourages the use of MFBIA as a bed-side technique for the serial assessment of body water compartments in patients with disturbances in fluid balance.

Journal Article↗
PubMed1997

Biological markers of protein-energy malnutrition.

The biological markers of undernutrition fall into three categories: (a) those that measure structure; (b) those that measure function; and (c) indices of the above two. Ideally a marker of nutritional status should have the following characteristics: specific to nutritional status; sensitive to changes in nutritional status; reproducible; simple to measure; inexpensive and widely available. Unfortunately there are no such markers, and therefore individuals involved in the assessment of nutritional status should be aware of the advantages and disadvantages of the markers they use. For example, body composition can be assessed using sophisticated techniques that make fewer assumptions than simple bedside techniques (1). However, these sophisticated techniques (eg neutron activation, and combinations of techniques such as hydro-densitometry, water dilution techniques and dual-energy X-ray absorptiometry) are not widely available and some of them are labour intensive. On the other hand simple bedside techniques, such as those based on skinfold thicknesses can be applied widely because they are easy and quick to perform, but they are probably not as accurate as the classic body composition techniques (hydro-densitometry or water dilution techniques) or other sophisticated methods based on the assessment of multiple body compartments (1). Therefore the choice of method depends not only on the availability of investigative tools, but also on the practicalities of using them in individuals, a small group of individuals, or large groups of individuals, (eg national surveys during famine and non-famine conditions). In this brief review only some aspects concerned with simple bedside or laboratory methods will be discussed.

Journal Article↗
PubMed1997

Plasma leptin, energy intake and hunger following total hip replacement surgery.

1. This study aimed to investigate the possible role of leptin in post-traumatic anorexia by making pre- and post-operative (0-8 days) measurements of circulating leptin concentrations in six patients undergoing elective total hip replacement for osteoarthritis. 2. Mean daily hunger rating (four categories) and food intake (assessed by food record charts) were measured pre-operatively, as well as post-operatively for the first 5 days (days 0-5). Leptin concentrations, circulating metabolites [glucose, non-esterified fatty acids, glutamine and 3-hydroxybutyrate] and insulin and cortisol concentrations were measured pre-operatively (day 0) and post-operatively (days 1, 2, 3, 5 and 8). 3. Mean leptin concentrations were significantly increased only on day 1 (56% increase compared with pre-operative values, P < 0.009), whereas food intake (only 0.6 MJ on day 0) and hunger (5/6 patients 'not hungry' on day 0) only gradually improved over the next few days. (The energy intake over the first 5 days was 56% of the pre-operative value.) 4. Circulating insulin and cortisol concentrations were elevated on day 1 compared with pre-operative values on day 0 (P < 0.05). Of the measured metabolites implicated in the control of food intake, circulating non-esterified fatty acids and 3-hydroxybutyrate were not significantly altered in the post-operative period, but significant hyperglycaemia was noted on day 1 compared with day 0 pre-operatively (8.8 compared with 6.4 mmol/l glucose; P < 0.01). 5. It is concluded that circulating leptin is involved in the early (< 24 h) acute-phase response after moderately severe surgical trauma (characterized biochemically by a substantial acute-phase protein response, hypoalbuminaemia, hyperglycaemia and hypoglutaminaemia). Therefore, leptin may be implicated in post-traumatic anorexia, although other factors are likely to be involved, especially after the first 24 h when circulating leptin concentrations are no longer elevated.

Acute-Phase Reaction↗
PubMed1997

Respiratory patterns during sleep in Down's syndrome:importance of central apnoeas.

Obstructive sleep apnoea episodes have been reported repeatedly in Down's syndrome (DS) patients as a consequence of the presence of predisposing malformations or intercurrent pathology of the upper airways. There are no data on respiratory patterns of uncomplicated Down's syndrome subjects. In order to evaluate the eventual effects of central nervous system (CNS) impairment on respiration in DS, we studied the respiratory patterns during sleep of a group of 10 DS subjects, aged 8.6-32.2 y, without relevant upper airway pathology. In order to control the possible effects of sleep structure and mental retardation on the results obtained, we compared the findings in DS with those obtained from a group formed by subjects affected by fragile X syndrome (six males and one female, aged 10.0-15.42 y) another genetically determined type of mental retardation. Sleep structure was similar in both groups; however, DS subjects showed significantly higher indices of central sleep apnoea and of oxygen desaturation than fragile X patients (P < 0.005). As far as DS individuals were considered, a significant preponderance of central, as opposed to obstructive, sleep apnoeas was found (89.4% vs. 9.4%, respectively; 1.2% were mixed) which showed a significant age-related increase. Central respiratory pauses were mostly preceded by sighs, which occurred more frequently during sleep stages 1 and REM, and were often organized in long sequences of periodic-like breathing. During REM sleep, they were less frequently preceded by sighs and by body movements than during NREM sleep. Obstructive sleep apnoeas occurred more often during REM sleep and were more rarely preceded by sighs or by body movements. Both central and obstructive apnoeas induced significant oxygen desaturation in 50-69.6%. Sleep structure was not significantly modified by apnoeas and oxygen desaturation. We hypothesize that the increase in central sleep apnoeas is related to a dysfunction of the central respiratory control at a brainstem level in DS.

Adolescent↗
PubMed1996

International Federation of Clinical Chemistry. Laboratory assessment of protein-energy status.

Laboratory and non-laboratory methods for assessing protein-energy nutritional status are reviewed. These are classified into methods for assessing adequacy of recent nutritional intake, methods for assessing whole body status, and tests which assist in the interpretation of these assessments. Each measurement is critically discussed in terms of the rationale for its use, the method of analysis, reference values, technical interference and limitations of methods, the effects of nutritional status and of other factors on the results, its overall usefulness in nutritional assessment, and its value relative to other methods. Non-laboratory tests such as dietary assessment, indirect calorimetry, functional tests and the many methods available for assessment of body composition, including anthropometry, bioelectrical impedance and isotope and imaging techniques, are compared with the clinical chemistry tests in common use, such as nitrogen balance, plasma protein measurements and urinary markers of muscle metabolism. This review provides comprehensive and practical advice on the use and limitations of these tests in the assessment of protein-energy nutritional status of a group, or of an individual patient.

Calorimetry↗
PubMed1996

Saethre-Chotzen syndrome: a clinical, EEG and neuroradiological study.

Saethre-Chotzen syndrome is a form of acrocephalosyndactyly with autosomal dominant inheritance, characterized by craniosynostosis, facial asymmetry, palpebral ptosis, deviated nasal septum, partial cutaneous syndactyly, and various skeletal abnormalities. We studied in detail the neurological, EEG, and neuroradiological features of a group of 11 (6 male, 5 female) patients with Saethre-Chotzen syndrome. Four subjects were affected by seizures; they had paroxysmal EEG abnormalities, and gross neuroimaging revealed destructive brain lesions or malformations. Our findings suggest that CNS involvement in Saethre-Chotzen syndrome might be more severe than previously reported and support the wider use of neurophysiological and neuroimaging techniques in the study of children with this syndrome.

Acrocephalosyndactylia↗