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Biomedical subjects

C Pichard

Publications and source records attributed to C Pichard.

106 records · Page 6Linked to original sources
PubMed1988

Effect of dietary manipulations (fasting, hypocaloric feeding, and subsequent refeeding) on rat muscle energetics as assessed by nuclear magnetic resonance spectroscopy.

31P nuclear magnetic resonance (NMR) spectroscopy in vivo and fluorometry were used to measure muscle ATP, total creatine, pH, and Mg2+ in vivo; and to calculate creatine phosphate (CrP), the ratios of CrP/inorganic phosphate (Pi), CrP/ATP, free ADP levels, and the free-energy change in ATP hydrolysis so nutritional effects could be ascertained. These parameters were determined in vivo in resting control, 2-d-fasted, and hypocalorically fed rats and in animals similarly hypocalorically fed and then refed. The ATP, Pi, and intracellular Mg2+ levels were comparable in the four groups. When the fasted and underfed animals were compared with the control and refed animals, there were falls in the ratios of CrP/Pi and CrP/ATP, in the calculated CrP, and the free-energy change of ATP hydrolysis, but a rise in the calculated free ADP. In the hypocaloric group, intracellular pH fell significantly and a large peak was noted in the phosphodiester region. The data are consistent with the hypothesis that ATP levels are maintained at the cost of CrP, suggesting that ATP production is disturbed by aerobic and anaerobic mechanisms.

Adenosine Diphosphate↗
PubMed1987

[Chronic salpingitis and extra-uterine pregnancy. Results of the histologic study of 215 tubal pregnancies].

215 women who had tubal pregnancy were treated by total salpingectomy at the University Hospital Port-Royal between the 1st January 1977 and the 30th January 1986. All of these had histological examination of the tube in which the pregnancy occurred. Our series of histological examinations confirms that tubal pregnancy occurs in the great majority of cases in a tube that is already pathological. The responsibility for tubal abnormalities in the occurrence of tubal pregnancy has been suggested by a comparative study of a control series where chronic lesions of the tube were statistically far less frequent (p less than 0.001). Ampullary pregnancy, of which there were 200 cases, was associated in 89.5% of the cases with a pathological condition of the ampulla. Isthmic pregnancy, of which there were 15 cases, would seem to be secondary to a pathology in the isthmus in all cases except one, and is nearly always associated with lesions in the ampulla. Chronic salpingitis was the main histological lesion that was observed. It represented 95.5% of the abnormalities of the ampulla in ampullary pregnancies. In isthmic pregnancies it was found in two-thirds of cases attacking the isthmus, the ampulla or the whole tube. Isthmic salpingitis nodosa was the second lesion that was observed in 40% of isthmic pregnancies. As far as endometriosis is concerned, it is very rare and occurred in only one case. Prevention of tubal pregnancy, therefore, necessarily must lie in preventing tubal infections and sexually transmitted diseases.(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic Disease↗
PubMed1984

Constant rate enteral nutrition in bucco-pharyngeal cancer care. A highly efficient nutritional support system.

The incidence of protein and calorie malnutrition in bucco-pharyngeal cancer patients is high and therefore nutritional support is indicated. Two methods of tube feeding, fractioned enteral (FEN) versus constant rate enteral nutrition (CREN) have been compared in a prospective study. Based on anthropometrical, biological and immunological criteria, patients on CREN showed a significant improvement of their post-operative protein state in comparison with patients on FEN. This difference was due to a better tolerance to CREN, which allowed a more appropriate protein and calorie intake. Furthermore the time of intravenous infusion was reduced in patients on CREN. In conclusion, CREN is a highly efficient feeding method for patients with head and neck cancer. It has the great advantage of being simple and cheap.

Anthropometry↗
PubMedDate not supplied

Fat-free and fat mass percentiles in 5225 healthy subjects aged 15 to 98 years.

OBJECTIVES: Fat-free mass (FFM) and fat mass (FM) are important in the evaluation of nutritional status. Bioelectrical impedance analysis (BIA) is a simple, reproducible method used to determine FFM and FM. Because normal values for FFM and FM have not yet been established in adults aged 15 to 98 y, its use is limited in the evaluation of nutritional status. The aims of this study were to determine reference values for FFM, FM, and percentage of FM by BIA in a white population of healthy adults, observe their differences with age, and develop percentile distributions for these parameters between ages 15 and 98 y. METHODS: Whole-body resistance and reactance of 2735 healthy white men and 2490 healthy white women, aged 15 to 98 y, was determined by 50-kHz BIA, with four skin electrodes on the right hand and foot. FFM and FM were calculated by a previously validated, single BIA formula and analyzed for age decades. RESULTS: Mean FFM peaked in 35- to 44-y-old men and 45- to 54-y-old women and declined thereafter. Mean FFM was 8.9 kg or 14.8% lower in men older than 85 y than in men 35 to 44 y old and 6.2 kg or 14.3% lower in women older than 85 y than in women 45 to 54 y old. Mean FM and percentage of FM increased progressively in men and women between ages 15 and 98 y. The results suggested that the greater weight noted in older subjects is due to larger FM. CONCLUSIONS: The percentile data presented serve as reference to evaluate deviations from normal values of FFM and FM in healthy adult men and women at a given age.

Adipose Tissue↗
PubMedDate not supplied

Body composition by X-ray absorptiometry and bioelectrical impedance in chronic respiratory insufficiency patients.

Nutrition assessment is important during chronic respiratory insufficiency to evaluate the level of malnutrition or obesity and should include body composition measurements. The appreciation of fat-free and fat reserves in patients with chronic respiratory insufficiency can aid in designing an adapted nutritional support, e.g., nutritional support in malnutrition and food restriction in obesity. The purpose of the present study was to cross-validate fat-free and fat mass obtained by various bioelectric impedance (BIA) formulas with the fat-free and fat mass measured by dual-energy X-ray absorptiometry (DXA) and determine the formulas that are best suited to predict the fat-free and fat mass for a group of patients with severe chronic respiratory insufficiency. Seventy-five patients (15 women and 60 men) with chronic obstructive and restrictive respiratory insufficiency aged 45-86 y were included in this study. Body composition was calculated according to 13 different BIA formulas for women and 12 for men and compared with DXA. Because of the variability, calculated as 2 standard deviations, of +/- 5.0 kg fat-free mass for women and +/- 6.4 kg for men for the best predictive formula, the use of the various existing BIA formulas was considered not clinically relevant. Therefore disease-specific formulas for patients with chronic respiratory insufficiency should be developed to improve the prediction of fat-free and fat mass by BIA in these patients.

Absorptiometry, Photon↗
PubMedDate not supplied

Comparison of four bioelectrical impedance analysis formulas in healthy elderly subjects.

BACKGROUND: Changes of body composition occur with aging and influence health status. Thus accurate methods for measuring fat-free mass (FFM) in the elderly are essential. OBJECTIVE: The purpose of this study was to compare FFM obtained by three bioelectrical impedance analysis (BIA) published formulas specific for the elderly and one equation intended for all age groups, with FFM derived from dual-energy X-ray absorptiometry (FFM(DXA)), in healthy elderly subjects. METHODS: Healthy Caucasian subjects over 65 years (106 women, age 75 +/- 6.2, body mass index 25.2 +/- 4.1 and 100 men, age 74.6 +/- 6.6, body mass index 25.8 +/- 3.0) were measured by DXA (Hologic QDR-4500) and BIA (Xitron, 50 kHz). FFM(BIA) was calculated by the published formulas of Deurenberg, Baumgartner, Roubenoff and Kyle and compared to FFM(DXA) by a Bland-Altman analysis. RESULTS: The Deurenberg and Roubenoff BIA formulas underestimated FFM compared to DXA by -7.1 and -2.9 kg in women and -6.7 and -2.3 kg in men, respectively. The Baumgartner formula overestimated FFM by 4.3 kg in women and 1.4 kg in men. The Kyle formula showed differences of 0.0 kg in women and 0.2 kg in men, and the limits of agreement of FFM(BIA (Kyle)) relative to FFM(DXA) were -3.3 and +3.3 kg for women and -3.8 and +4.3 kg for men. CONCLUSION: The Kyle BIA formula accurately predicts FFM in elderly Swiss subjects between 65 and 94 years, with a body mass index of 17 to 34.9 kg/m(2). The other BIA formulas developed especially for the elderly are not valid in this population.

Age Factors↗
PubMedDate not supplied

Reliable bioelectrical impedance analysis estimate of fat-free mass in liver, lung, and heart transplant patients.

BACKGROUND: Bioelectrical impedance analysis (BIA) can be valuable in evaluating the fat-free (FFM) and fat masses (FM) in patients, provided that the BIA equation is valid in the subjects studied. The purpose of the clinical evaluation was to evaluate the applicability of a single BIA equation to predict FFM in pre- and posttransplant patients and to compare FFM and FM in transplant patients with healthy controls. METHODS: Pre- and posttransplant liver, lung, and heart patients (159 men, 86 women) were measured by two methods-50-kHz BIA-derived FFM (FFM(BIA)) by Xitron instrument and DXA-derived FFM (FFM(DXA)) by Hologic QDR-4500 instrument-and compared with healthy controls (196 men, 129 women), aged 20 to 79 years. RESULTS: The high correlation coefficient (r = .974), small bias (0.3 +/- 2.3 kg), and small SEE (2.3 kg) suggest that BIA using the GENEVA equation is able to predict FFM in pre- and posttransplant patients. The study shows that the lower weight seen in transplant men and women than in controls was due to lower FFM, which was partially offset by higher FM in men but not in women. Furthermore, the higher weights in posttransplant than in pretransplant patients were due to higher FM and % FM that was confirmed by lower FFM/FM ratio in posttransplant patients. CONCLUSIONS: Single 50-kHz frequency BIA permits measurement of FFM in pre- and posttransplant patients.

Absorptiometry, Photon↗
PubMedDate not supplied

Effects of L-carnitine supplemented total parenteral nutrition on lipid and energy metabolism in postoperative stress.

During episodes of trauma carnitine-free total parenteral nutrition (TPN) may result in a reduction of the total body carnitine pool, leading to a diminished rate of fat oxidation. Sixteen patients undergoing esophagectomy were divided randomly in two equal isonitrogenous groups (0.2 g/kg.day). Both received TPN (35 kcal/kg.day; equally provided as long-chain triglycerides and glucose) over 11 days without (group A) and with (group B) L-carnitine supplementation (12 mg/kg.day = 75 mumol/kg.day). Compared with healthy controls, the total body carnitine pool prior to the operation was significantly reduced in both groups, suggesting a state of semistarvation and muscle wasting. In group A the plasma levels of total carnitine and its subfractions (free carnitine, short- and long-chain acylcarnitine) remained stable during the study whereas in group B the total plasma carnitine concentration rose mainly due to an increase in free carnitine. In group A the cumulative urinary carnitine losses were 11.5 +/- 2.6 mmol (= 15.5 +/- 3.1% of the estimated total body carnitine pool). In group B 3.1 +/- 1.9 mmol (= 11.1 +/- 7.6%) of the infused carnitine was retained in the immediate postoperative phase until day 6, but this amount was completely lost at completion of the study period. No significant differences in the respiratory quotient or in the plasma levels of triglycerides, free fatty acids, and ketone bodies were observed, between or within the groups, before the operation and after 11 days of treatment. It is concluded that the usefulness of carnitine supplementation during postoperative TPN was not apparent in the present patient material.

Adult↗
PubMedDate not supplied

Comparative clearance of two new fat emulsions--Hausmann Lipid 20% and Lipovenös 20%--versus intralipid 20%.

Intravenous fat tolerance tests (IVFTT) were performed in 13 healthy men volunteers once a day during three consecutive days in order to compare three different fat emulsions randomly administered (Intralipid 20%, Hausmann Lipid 20%, Lipovenös 20%). The amount of fat was 0.1 g/kg of body weight injected within 32 +/- 4 sec and the lipid clearance was determined over 40 min. The fractional removal rates k for the three different emulsions of fat were 5.38 +/- 1.67, 4.95 +/- 2.15, 3.92 +/- 1.31 %/min, respectively (mean +/- SD), and the half-life time of clearance T1/2 were 14.5 +/- 5.8, 16.9 +/- 7.4, 19.2 +/- 5.2 min, respectively. The highest fat particles values were observed 5 min after the bolus and all concentrations remained within the normal range (0-3 g/liter) during the study. In addition, no adverse effects were observed throughout the IVFTT. The nonparametric analysis of variance (Friedman's test) showed no significant differences between groups, even if Lipovenös 20% tended to be cleared more slowly than Intralipid 20%. These results suggest that the three fat emulsions are similarly eliminated from the blood stream and do not result in acute intolerance. Further studies based on prolonged infusion should be carried out to determine whether the two new emulsions might be alternatively used for intravenous nutritional support.

Adult↗
PubMedDate not supplied

Validation of a new formula for calculating the energy requirements of burn patients.

In a previous study, we analyzed the roles of the estimated basal energy expenditure (EBEE) calculated by the Harris-Benedict equation, caloric intake (CI), total burn surface area (TBSA), body temperature (Temp) and number of post-burn days (PBD) in order to estimate the resting energy expenditure (EE) of burn patients. By multiple regression analysis we found that the measured EE (MEE) is best approximated by the following formula: -4343 + (10.5 x %TBSA) + (0.23 x CI) + (0.84 x EBEE) + (114 x Temp (degree C)) - (4.5 x PBD), r = 0.82, p less than 0.001, (Toronto formula (TF)). To validate this, 10 patients with a mean TBSA of 49.1 +/- 5.5% had their resting MEE done by indirect calorimetry when fed either by the TF or by 2 x EBEE. The caloric intake when on 2 x EBEE was 3260 +/- 45 kcal/day which significantly exceeded the MEE (2765 +/- 101 kcal/day, p less than 0.001). The caloric intake when on the TF was 2542 +/- 52 kcal/day and matches the MEE which was 2537 +/- 86 kcal/day (NS). These results show that the TF matches the MEE very closely. With the addition of a factor of activity for the 24-hr EE, it can be used to accurately feed individual burn patients.

Adult↗
PubMedDate not supplied

Vitamin E suppresses increased lipid peroxidation in cigarette smokers.

Cigarette smoke contains many xenobiotics, including oxidants and free radicals, which can increase lipid peroxidation. Recently, breath pentane output (BPO) has been recognized as a good indicator of lipid peroxidation. Vitamin E is known to be a potent free radical scavenger which can protect biological membranes against oxidative damage. We investigated the effect of vitamin E (dl-alpha-tocopherol) on lipid peroxidation in 13 healthy smokers. The results showed (1) smokers had increased BPO as compared with 19 healthy non-smokers (16.3 +/- 1.9 vs 5.8 +/- 0.5, pmol/kg body weight/min, p less than 0.001) although both groups had comparable plasma vitamin E and selenium concentrations, (2) supplementation with vitamin E (800 mg/day for 2 weeks) decreased BPO in smokers, and (3) the concentration of plasma selenium-dependent glutathione peroxidase was restored to normal in those smokers (five out of 13) in whom this was low initially. We conclude that a normal plasma concentration of vitamin E does not prevent this increase of lipid peroxidation in smokers but that substantial doses of vitamin E will significantly reduce this increased lipid peroxidation. If a major function of vitamin E is to protect lipids from peroxidation, then smokers have a conditioned insufficiency of vitamin E on a normal diet.

Adult↗
PubMedDate not supplied

Effect of parenteral medium- and long-chain triglycerides on lymphocytes subpopulations and functions in patients with acquired immunodeficiency syndrome: a prospective study.

BACKGROUND: Total parenteral nutrition (TPN) may offer significant clinical benefit in malnourished patients with acquired immunodeficiency syndrome (AIDS). However, the immunologic effect of parenteral lipids remains unknown in these severely immunodepressed patients. METHODS: We undertook a prospective randomized double-blind multicenter study comparing the effects of two i.v. lipid emulsions used during TPN: long-chain triglycerides (LCT) or balanced emulsion of long-and medium-chain triglycerides (LCT/MCT). Thirty-three AIDS patients requiring TPN for wasting and reduced oral intake were allocated randomly to receive a ternary TPN mixture consisting of 1.5 g/kg/d proteins, 18 kcal/kg/d lipids, and 12 Kcal/kg/d carbohydrates for 6 days. The following tests were performed at days 0 and 7: immunoglobulins, complement fractions, lymphocyte subpopulations count, and lymphocyte proliferation with mitogens. RESULTS: Patients were all severely malnourished (weight loss: -14.0 +/- 1.3 kg). No clinical or biological differences were observed between the groups at baseline. At day 7, both groups reported a significant increase in weight. Patients in the LCT group exhibited a significant decrease in phytohemagglutinin A response (p = .04) compared with baseline. Patients in the LCT/MCT group exhibited a lower level of IgM (p = .03) and significant increase in C3 fraction (p = .03) compared with baseline. They also showed a tendency to have a higher CD4/CD8 lymphocyte ratio (p = .07), whereas other immunological parameters remained unchanged CONCLUSIONS: Parenteral ternary mixture containing LCT or LCT/MCT are clinically well tolerated in AIDS patients over 6 days. With 2 g/kg/d of lipids, LCT seems to induce significant abnormalities in lymphocyte function. Such abnormalities are not observed with LCT/MCT.

Acquired Immunodeficiency Syndrome↗