Clinical presentation and time course in hypersensitivity reactions to beta-lactams.

Background: beta-lactam hypersensitivity reactions are classified as immediate or nonimmediate. Diagnosis is usually based upon skin tests and provocation challenges.

Objective: The time course of the reactions in proven beta-lactam hypersensitivities was studied and then correlated with the symptoms to determine the relationship between the clinical presentations and the time course.

Diagnosis of neuromuscular blocking agent hypersensitivity reactions using cytofluorimetric analysis of basophils.

Background: Immunoglobulin E (IgE)-mediated hypersensitivity reactions to neuromuscular blocking agents (NMBA) are common and life threatening. Basophil activation based upon the expression of CD63 in the presence of specific allergens was found to be of importance for the diagnosis of IgE-mediated hypersensibility.

Methods: The Basotest was evaluated for the diagnosis of NMBA in 47 patients with proven NMBA anaphylaxis, 40 atopic subjects nonallergic to NMBA and five healthy volunteers.

Confirmation of the diagnosis of natural rubber latex allergy by the Basotest method.

Background: The flow cytometry CD63-based basophil activation test (Basotest has already been validated for the diagnosis of immediate-type allergy such as venom, house dust mite or cypress pollen allergies. The aim of this study was to evaluate the performance (specificity and sensitivity) of Basotest in the diagnosis of natural rubber latex allergy.

Methods: We included 46 latex allergic patients (clinical symptoms of latex allergy, positive latex skin prick tests and/or latex specific IgE) and 33 control subjects and performed Basotest on all subjects.

Increased bronchoalveolar lavage CD8 lymphocyte subset population in wheezy infants.

Episodes of wheezing are very common in infancy but, despite their high prevalence, their mechanism is still poorly understood. To better understand the airway inflammation of wheezing infants, we examined cells of the bronchoalveolar lavage (BAL), focusing on the phenotype of lymphocytes and macrophages by using cytofluorimetry. Twenty-one wheezers (mean age 15.

Cysteinyl-leukotriene release test (CAST) in the diagnosis of immediate drug reactions.

Background: The diagnosis of allergic reactions to drugs is difficult. Most skin tests are not standardized, and in vitro tests are needed to avoid provocation tests. Cross-linking of IgE on basophils is known to cause the release of both cysteinyl leukotriene (Cys-LT) and histamine.

Duodenal vs. gastric administration of labeled leucine for the study of splanchnic metabolism in humans.

Low-rate (6 ml/h) intragastric infusion of stable, isotope-labeled amino acids is commonly used to assess the splanchnic handling of amino acids in humans. However, when used in the postabsorptive state, this method yields unreliable plasma isotopic enrichments, with a coefficient of variation >10%. In this metabolic condition, we confirmed in six subjects that an intragastric infusion of L-[(2)H(3)]leucine at 6 ml/h yields an unreliable isotopic steady state in plasma amino acids with a coefficient of variation of 43 +/- 12% (mean +/- SD).

Predictive capacity of histamine release for the diagnosis of drug allergy.

Background: The diagnosis of immediate allergic reactions to drugs is difficult, requiring in vitro test development. Basophils are likely to be involved in these reactions, and to evaluate the sensitivity, the specificity, and the predictive values of the histamine-release test, we performed a prospective study in 68 patients tested for suspected drug allergy.

Methods: Positive diagnosis was established by history, skin tests, and, if needed, oral provocation tests.

Energy and protein metabolism during recovery from malnutrition due to nonneoplastic gastrointestinal disease.

The magnitude of metabolic adaptation to malnutrition is still debated and few studies have investigated the phase of recovery from malnutrition. The aim of the present work was to determine whether refeeding was associated with adaptive changes in 1) energy expenditure, 2) maximal capacity for oxidizing lipids, and 3) whole-body protein turnover. Eleven malnourished patients with nonneoplastic gastrointestinal diseases were studied by using indirect calorimetry and L-[1-13C]leucine infusion while being infused with lipid-rich total parenteral nutrition (TPN).

Energy and protein metabolism in malnutrition due to nonneoplastic gastrointestinal diseases.

Although a reduction in both energy expenditure and protein turnover has been demonstrated in starved volunteers, few metabolic data are available for patients in whom malnutrition is due to nonneoplastic gastrointestinal diseases. Chronically malnourished, unstressed adult patients with nonneoplastic gastrointestinal diseases (body mass index, 15.8 +/- 2.

Glutamine metabolism in children with short-bowel syndrome: a stable isotope study.

Because glutamine is thought to be a major fuel for developing gut, we tested the hypothesis that extensive small-bowel resection alters whole-body glutamine metabolism in vivo. Eleven infants and children who had undergone extensive small intestinal resection (residual bowel length: 35 +/- 13 cm; mean +/- SD) and four control infants received 4-h primed, continuous i.v.

Glutamine metabolism in healthy adult men: response to enteral and intravenous feeding.

To assess the effect of feeding on glutamine kinetics, six healthy men received 4-h intravenous infusions of L-[2-15N]glutamine and L-[1-13C]leucine on 3 separate days: 1) in the postabsorptive state, 2) over the course of an 8-h nasogastric infusion of a small peptide-based nutrient mixture, and 3) during an 8-h isonitrogenous, isoenergetic intravenous infusion (1.5 g amino acid.kg-1.

Leucine metabolism at graded amino acid intakes in children receiving parenteral nutrition.

To assess the response of protein turnover to graded levels of amino acid (AA) intakes, leucine kinetics were determined in six 8- to 16-yr-old patients in a stable nutritional status receiving home parenteral nutrition (PN) for short-bowel syndrome or intestinal pseudo-obstruction syndrome. Although daily energy intake was kept constant at 68.7 +/- 13 kcal/kg lean body mass (LBM) with 25.

[15N]- and [14C]glutamine fluxes across rabbit ileum in experimental bacterial diarrhea.

L-Glutamine (Gln) fluxes and the effects of Gln on Na and Cl transport were studied across the ileum of healthy and rabbit diarrheagenic Escherichia coli (RDEC-1)-infected weanling rabbits. Stable ([alpha-15N]Gln) and radioisotopic ([U-14C]Gln) tracers provided identical estimates of Gln transport both in healthy (H) and infected (I) rabbits. RDEC-1 infection, however, decreased net Gln flux [Jnet[14C]Gln = 682 +/- 147 (H) vs.

Urinary excretion of iodide and fluoride from supplemented food grade salt.

Iodide and fluoride supplemented food grade salt (NaCl) is a common source of these two micronutrients. In a pilot study, we investigated whether increased intake of NaCl supplemented with iodide (I-) and fluoride (F-) results in their higher bioavailability. Twelve healthy adult human volunteers ingested increasing quantities (1, 3, 6 and 9 g) of NaCl with usual diet over 8 days.

Glutamine nitrogen kinetics in insulin-dependent diabetic humans.

To assess the effect of insulin deficiency on whole body glutamine kinetics, five young adults with type I (insulin-dependent) diabetes received 4-h primed continuous infusions of L-[1-13C]leucine and L-[2-15N]glutamine in the postabsorptive state after blood glucose had been clamped overnight at either a normoglycemic level (approximately 85 mg/dl) or a moderate hyperglycemic level (approximately 260 mg/dl) by means of an automated glucose control insulin infusion system. The hyperglycemic state was associated with a significant rise in leucine level [from 165 +/- 23 to 242 +/- 62 (SD) microM], appearance rate (from 125 +/- 11 to 142 +/- 17 mumol.kg-1.

Intestinal absorption of free oral hyperalimentation in the very short bowel syndrome.

Ten adult ambulatory patients with the nonactive digestive disease short bowel syndrome were prospectively studied to quantitatively assess their free oral intake and their net digestive absorption of total calories, fat, protein, and carbohydrate during a 3-day period at least 6 months after a resection. The remaining portions of small bowel had a mean length of 75 cm (range, 0-200 cm); the remaining colon lengths had a mean of 67% of normal (range, 0%-100%). The experimental diets were formulated according to a home dietary inquiry.

Absorption and metabolic effects of enterally administered glutamine in humans.

To assess absorption and metabolic effects of enterally delivered glutamine, a total of 10 healthy subjects received perfusions of natural L-glutamine at graded infusion rates (ranging from 0 to 126 mmol/h; n = 2-8 subjects at each rate) along with a nonabsorbable marker (polyethylene glycol) through a double-lumen nasojejunal tube. Perfusions were administered after an overnight fast during three consecutive 1- or 2.5-h periods and in a randomized order.

Glutamine metabolism after small intestinal resection in humans.

Glutamine and leucine kinetics were measured using stable isotopes in five enterectomized patients (residual small bowel, 80 +/- 25 cm [mean +/- SE]) who were in a near normal nutritional status at distance from surgery. While parameters of leucine metabolism were normal, rates of whole body glutamine utilization were reduced by 20% in the patients. The data suggest that the small intestine plays a prominent role in glutamine utilization in vivo in humans.

Use of a ventilated canopy for assessment of [13C]leucine oxidation in patients receiving total parenteral nutrition.

Rates of oxidation of infused 13C-labeled substrates are calculated from CO2 production and 13C enrichment in breath CO2. Breath sampling through a mouthpiece is not appropriate in severely ill patients; the authors therefore validated the use of direct air sampling from the ventilated canopy of an indirect calorimeter for measuring the oxidation of 13C-labeled substrates. Infusions of H13CO3Na or L-[1-13C]leucine were performed in four healthy postabsorptive adults and six malnourished patients receiving total parenteral nutrition (TPN).

Intestinal absorption of amiodarone in man.

The jejunal absorption rate of amiodarone and the influence of lipids on it were studied in human volunteers using the intestinal perfusion technique. A nutrient solution (Realmentyl, Sopharga Laboratories, France) with 300 mg of the drug was infused for 120 minutes at the ligament of Treitz. The segment tested was 25 cm long.

Comparison of substrate utilization by indirect calorimetry during cyclic and continuous total parenteral nutrition.

Five male adult home patients were studied in a randomized order under continuous (24 h/d) and nocturnal cyclic (15 h/d) isocaloric, isonitrogenous total parenteral nutrition (TPN). They received 2626 +/- 265 total kcal/d as 60% dextrose and 40% lipids; the 3-h lipid infusion was followed by the dextrose amino acid infusion on both regimens. Substrate oxidation was measured by indirect calorimetry during four periods on the fourth day of each regimen.

Amino acid exchange between plasma and erythrocytes in vivo in humans.

To study amino acid exchange between plasma and erythrocytes in vivo, 4-h primed, continuous intravenous infusions of L-[1-13C]leucine, [15N]glycine, and L-[15N]alanine were administered to five healthy young men in the postabsorptive state. Stable isotope enrichments and amino acid levels were determined by gas chromatography-mass spectrometry in both plasma and whole blood and estimated (using hematocrit) in erythrocytes. A high concentration gradient across the erythrocyte membrane was consistently found for glycine (552 +/- 268 microM in erythrocytes vs.

Glutamine transport in isolated rabbit ileal epithelium.

Oral rehydration therapy of diarrhea is based upon the promoting effect of glucose on sodium absorption. This ionic transport could be further enhanced by the addition of glutamine, an amino acid which is also the major energy source for the enterocyte. The aim of this in vitro study was to assess glutamine intestinal transport and to evaluate ionic movements associated with this transport.

Evaluation of the gastric absorption and emptying of drugs under various pH conditions using a simple intubation method: application to diclofenac.

Sodium diclofenac (50 mg) together with [14 C]-PEG as a non-absorbable marker were dissolved in 400 ml of water (A), phosphate buffer pH 7.5 (B) or a homogenized meal (C). Each of these was ingested in random order by six volunteers on 3 consecutive days.