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Biomedical subjects

C Champagne

Publications and source records attributed to C Champagne.

At least 19 recordsLinked to original sources
PubMed1998

Diet design for a multicenter controlled feeding trial: the DELTA program. Delta Research Group.

OBJECTIVE: To describe the process and results of diet standardization, diet validation, and monitoring of diet composition, which were key components of protocol 1 of Dietary Effects on Lipoproteins and Thrombogenic Activity (DELTA-1), the initial protocol in a program of multicenter human feeding studies designed to evaluate the effects of amount and type of fat on lipoproteins and hemostasis parameters in various demographic groups. DESIGN: DELTA-1 was based on a randomized, blinded, crossover experimental design. Three diets were fed for 8 weeks to 103 healthy men and women aged 22 to 67 years at 4 field centers. Diet A, an average American diet, was designed to provide 37% of energy from fat, 16% of energy from saturated fatty acids (SFAs); diet B (step 1 diet) was designed to provide 30% of energy from fat, 9% of energy from SFA; and diet C (low SFA diet) was designed to provide 26% of energy from fat, 5% of energy from SFA. Key features of diet standardization included central procurement of fat-containing foods, inclusion of standard ingredients, precision weighing of foods--especially sources of fat and cholesterol--and use of standardized written procedures. SETTING: For menu validation, a set of 12 menus for each diet was prepared in duplicate and chemically assayed. For monitoring of diet composition during the study, an 8-day diet cycle (6 weekday and 2 weekend menus) was sampled by every field center twice during each of 3 feeding periods. STATISTICAL ANALYSES: Means (+/- standard error) were calculated and compared with target nutrient specifications. RESULTS: DELTA-1 was able to provide a standardized diet that met nutrient specifications across 4 field centers over 24 weeks of participant feeding spanning a total of 8 months. APPLICATIONS: Prestudy chemical validation of menus and continuous sampling and assay of diets throughout the study are essential to standardize experimental diets and to ensure that nutrient target goals are met and maintained throughout a controlled multicenter feeding study.

Adult↗
PubMed1998

Strain-dependent activation of monocytes and inflammatory macrophages by lipopolysaccharide of Porphyromonas gingivalis.

Porphyromonas gingivalis is one of the pathogens associated with periodontal diseases, and its lipopolysaccharide (LPS) has been suggested as a possible virulence factor, acting by stimulation of host cells to secrete proinflammatory mediators. However, recent studies have shown that P. gingivalis LPS inhibited some components of the inflammatory response. The present study was designed to test the hypothesis that there are strain-dependent variations in the ability of P. gingivalis LPS to elicit the host inflammatory response. By using LPS preparations from two strains of P. gingivalis, W50 and A7346, the responses of mouse macrophages and human monocytes were evaluated by measuring the secretion of nitric oxide (NO) and tumor necrosis factor alpha (TNF-alpha). Both direct and indirect (priming) effects were investigated. LPS from Salmonella typhosa was used as a reference LPS. P. gingivalis A7436 LPS induced lower secreted levels of NO from the tested cells than S. typhosa LPS but induced similar levels of TNF-alpha. In contrast, LPS from P. gingivalis W50 did not induce NO or TNF-alpha secretion. Preincubation of macrophages with LPS from S. typhosa or P. gingivalis A7436 prior to stimulation with S. typhosa LPS upregulated NO secretion and downregulated TNF-alpha secretion, while preincubation with P. gingivalis W50 LPS enhanced both TNF-alpha and NO secretory responses. These results demonstrate that LPSs derived from different strains of P. gingivalis vary in their biological activities in vitro. The findings may have an impact on our understanding of the range of P. gingivalis virulence in vivo.

Animals↗
PubMed1996

Essential fatty acid deficiency and home total parenteral nutrition patients.

The requirements for essential fatty acids in patients on home parenteral nutrition are not well described. We therefore studied the needs of 12 patients receiving parenteral nutrition for at least 4 mo (range: 4 mo-17.3 yr; mean 7.0 +/- 5.2 yr). Prior to the study, each patient had been receiving intravenous lipids either weekly or biweekly and had a triene to tetraene ratio (TTR) on plasma phospholipids performed at least annually. A TTR > or = 0.2 was considered diagnostic for essential fatty acid deficiency (EFAD). The purpose of this study was to determine the required intravenous lipid supplementation in patients on home total parenteral nutrition (HTPN). Patients with an initial TTR of < 0.2 had their intravenous lipid stopped and changes in their serum phospholipid fatty acids were followed every 3-4 wk. Nine of 12 patients had TTRs > 0.2 at some point in the study. Phase I consisted of patients who at initiation of the study had normal TTRs and were taken off lipid supplementation until their TTR became abnormal. Phases II, III, IV, and V consisted of lipid delivered in total nutrient admixtures in biweekly doses of 0.6, 1.2, 1.8, and 2.4 g of fat/kg bodyweight, respectively. Eight patients normalized their TTRs on the biweekly lipid regimens; one patient expired before his ratio normalized; and three patients could not be made deficient in essential fatty acids after 26 or more wk of fat-free parenteral nutrition. Most patients required 1.2 to 2.4 g of lipid/kg bodyweight/biweekly to correct serologic EFAD. The clinical background, as well as the length of small bowel remaining, did not seem to identify those patients who required lipid supplementation nor the final dose of lipid needed to normalize their TTRs.

Adult↗
PubMed1995

Lipopolysaccharide priming of superoxide release by human neutrophils: role of membrane CD14 and serum LPS binding protein.

Previous studies have suggested that lipopolysaccharide (LPS) interactions with neutrophils and monocytes are mediated via the CD14 receptor, in the presence of serum factors such as LPS-binding protein (LBP) and septin. The present study was designed to test if CD14-mediated LPS priming of human neutrophils is dependent upon the presence of serum proteins and to evaluate the contribution of serum factors in LPS-neutrophil interactions. The results demonstrate that CD14 mediates the priming of neutrophil superoxide release by LPS both in the presence and in the absence of serum. However, priming by LPS is greatly enhanced in the presence of human serum, and the factor responsible for this phenomenon is LBP and not heat-sensitive proteins, such as septin.

Acute-Phase Proteins↗
PubMed1995

Diet in the prevention and treatment of atherosclerosis. A perspective for the elderly.

Atherosclerosis is the leading cause of coronary heart disease among older persons. With an increasing elderly population, cardiovascular disease has become an urgent public health concern. Diet plays an important role in atherogenesis with known beneficial effects on major risk factors among the younger population--cholesterol, hypertension, and diabetes. Intervention studies are needed to establish the benefits of diet therapy in the elderly segment of the population. Efforts are also needed to educate the elderly and health professionals about the benefits of a healthy Step I diet.

Age Distribution↗
PubMed1995

Nutrition assessment practical approaches.

Because of the insidious nature of malnutrition in the elderly and its mimicking the usual aging process, it is important to recognize early warning signs of risks for malnutrition. Because the majority of individuals are encountered at times of a specific event (i.e., illness, injury, surgery, or annual examination) the physician needs to be cognizant of the triggers or alerts of poor nutritional health during history/physical and laboratory examinations for the particular event. Only then will early detection and applicable interventions provide a salutary paradigm shift towards prevention, whether primary, secondary, or tertiary. A high degree of suspicion, a thorough history, and physical examination coupled with pertinent laboratory data can identify the elderly at risk. Those in need of more comprehensive nutrition screen and assessment are examined with the tools developed by the NSI, which encompass not only the routine medical and dietary history and physical exam but also an expansive look at the older individual's psychosocial, functional, socioeconomic, and drug use aspects that are more indirect and significant determinants of risk. Based on parameters from a Level II Screen, measurable indicators are available that provide the nutrition assessment necessary for an overall healthcare plan of selected interventions. Future research should provide more practical, age, sex, and culturally specific nutrition parameters. The main factor in the implementation of a practical, comprehensive geriatric nutrition screening and assessment program is the clinician's imagination and motivation.

Aged↗
PubMed1994

Involvement of protein kinase C and protein tyrosine kinase in lipopolysaccharide-induced TNF-alpha and IL-1 beta production by human monocytes.

Bacterial LPS stimulates human monocytes to secrete inflammatory cytokines, which are involved in several disease processes. However, the mechanism of LPS activation of cytokine expression and secretion is not completely understood. In this study, we investigated the signal transduction pathways involved in LPS-stimulated TNF-alpha and IL-1 beta secretion. TNF-alpha and IL-1 beta secretion were completely blocked by protein kinase C (PKC) and cyclic nucleotide-dependent protein kinase inhibitor, H-7, but were not affected by H-89, a specific cyclic nucleotide-dependent protein kinase inhibitor. In addition, LPS was found to induce activation of PKC, reaching maximal activity at 30 min and returning to unstimulated levels after 60 min. LPS stimulation only slightly increased intracellular levels of diacylglycerol, the natural activator of PKC, and pretreatment of monocytes with the diacylglycerol-kinase inhibitor, R59022, did not affect LPS-stimulated TNF-alpha secretion. LPS-induced PKC activation was found not to be affected by blocking of the LPS receptor, CD14, with mAb or by inhibition of protein tyrosine kinase with herbimycin A. However, these agents suppressed LPS-induced TNF-alpha secretion and TNF-alpha mRNA accumulation. The results suggest that TNF-alpha and IL-1 beta secretion after LPS stimulation of human monocytes requires the activation of protein tyrosine kinase and PKC, upstream to the activation of gene transcription. The activation of PKC by LPS is probably mediated by a diacylglycerol-independent pathway.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1994

Validity and reliability of reported dietary intake data.

OBJECTIVE: To compare two training techniques for validity and reliability of dietary instruments and the measurement of total energy expenditure (TEE) to determine whether technique could influence the accuracy of food portion estimates. DESIGN: Adult women were randomized into a control group and an experimental group for comparison of training technique. SETTING: University and research center. SUBJECTS: Five hundred women were screened using the Three-Factor Eating Questionnaire to identify restrained eaters or disinhibitors. Other criteria for selection included good health; absence of thyroid, respiratory, or other diseases; normal menstrual cycles; between the ages of 18 and 50 years. Forty-nine were recruited, with an attrition rate of 10% for a total sample of 44 subjects. INTERVENTION: The control group (n = 26) was trained with food models and the experimental group (n = 18) was trained with a combination of food models and life-sized food photographs. All subjects completed two 24-hour recalls and 14 consecutive days of food records. TEE was measured by the doubly-labeled water method. MAIN OUTCOME MEASURES: Training would improve the accuracy of food portion estimates. STATISTICAL ANALYSES PERFORMED: Analysis of variance, the paired t test, Pearson's correlation coefficient, and Wilcoxon's ranking test. RESULTS: The mean reported intake between instruments was found to be reliable; however, the comparison with TEE was underreported by 21.4% and was thus nonvalid. Training technique made no difference in validity or reliability. Both training techniques improved the accuracy of food portion estimates; however, improvement was enhanced with food photographs. APPLICATIONS/CONCLUSION: The findings indicate that training can improve food portion estimates, and dietary instruments may provide reliable but nonvalid results.

Adult↗
PubMed1992

Altered diacylglycerol level and metabolism in neutrophils from patients with localized juvenile periodontitis.

Diacylglycerol, a physiological activator of protein kinase C, was elevated nearly twofold in unstimulated peripheral blood neutrophils from patients with localized juvenile periodontitis compared with cells from normal individuals. These cells also showed an enhanced and prolonged elevation of diglyceride in response to N-formylmethionylleucylphenylalanine. The metabolism of a cell-permeant diacylglycerol by diglyceride kinase was significantly decreased, because of a fivefold or higher elevation in the apparent Km of cellular diglyceride kinase.

Adult↗
PubMed1992

[Analgesic effect of transcutaneous cranial electrostimulation in patients treated by Nd:YAG laser for cancer of the rectum. A double-blind randomized trial].

The aim of this double blind cross-over randomized trial was to assess if transcutaneous cranial electrical stimulation by Limoge current could decrease the dose of fentanyl required in patients with rectal cancer treated by Nd:YAG laser. Fifty patients, 29 women, 21 men, 78 +/- 10 years old (range: 53-96 years), were treated by 2 laser sessions with an interval of 48 hours between each session. Active and sham electrostimulation were given in random order for the 2 laser sessions. The major end point was the quantity of fentanyl injected when the score of pain was greater than or equal to 5 according to a visual analgesic scale. Age, sex, body weight, tumor location and length, tumor circumferential extent and luminal patency, duration of laser session, amount of energy delivered per session (watt-seconds), and number of patients with deep sedation did not differ between the 2 groups. There was no interaction between the order of treatments and the treatments. The mean quantity of fentanyl was 29 micrograms and 42 micrograms when sham electrostimulation was given. There was a decrease of 31 percent in the quantity of fentanyl with active electrostimulation (P less than 0.05). Results were not affected either by the treatment order nor by tumor location. There were no side effects in either group.

Aged↗
PubMed1986

Variations of glucocorticoid receptors in intact or denervated muscles: lack of cause-effect relationship with muscle atrophy in the rat.

The process of muscular atrophy following denervation has been tentatively ascribed to the influence of glucocorticoids (G) because of the rapid increase of cytosolic G receptors (RG) after sciatic nerve section. It appears however that the level of muscular atrophy is similar: in slow or fast-twitch muscles in spite of huge variations in RG; in intact or adrenalectomized (ADR-X) rats. Moreover, the protein muscle profile of intact of ADR-X rats after gel electrophoresis is similar but drastically decreased after 3 weeks of denervation. We conclude that there is no cause-effect relationship between muscle atrophy and RG elevation after nerve section.

Adrenal Glands↗
PubMed1985

Modulation of a major 30-kDa skeletal muscle protein by thyroid hormone.

Thyroidectomy results in the transformation of type II fibres to type I in rat soleus muscle. In vitro translations containing polyribosomes indicate that the template activity of mRNA coding for a 30-kDa protein is increased in hypothyroid (6 months) rats. The cellular content of this protein is also increased in hypothyroid rats. The in vitro synthesis of the 30-kDa protein is not observed in thyroidectomized (10 weeks) rats that have been treated with triiodothyronine. The synthesis and accumulation of this protein are directly related to the proportion of type I fibres in rat skeletal muscle and appear to be modulated by thyroid hormone.

Animals↗