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J P Mallié

Publications and source records attributed to J P Mallié.

At least 19 recordsLinked to original sources
PubMed2003

Brown Norway rat ovalbumin-specific immunoglobulin E antibodies increase the human basophil expression of CD63 marker.

Anaphylactic shock is an immunoglobulin E (IgE)-dependent hypersensitivity. Biological tests like leucocyte histamine release (LHR) and human basophil activation (HBA), frequently used in human allergy, reflect both the amount of IgE fixed on cells and the cellular reactivity. To assess whether serum-specific IgE from Brown Norway (BN) rats prepared for ovalbumin (OVA)-induced anaphylactic shocks can activate human basophils which has a potential interest in experimental allergy: such a test could rapidly assert an IgE sensitization in laboratory animals genetically T-helper 2 (Th2)-predisposed. Rats (n = 39) were immunized three times (day 0, day 5 and day 21) with OVA injected subcutaneously. One week after the third immunization, a shock was induced with an intravenous (i.v.) bolus of OVA. Sensitization was assessed by passive cutaneous anaphylaxis (PCA) test and dosages of serum IgE antibodies anti-OVA by enzyme-linked immunosorbent assay. Blood basophils were counted before and during the shock. Before the shock induction (at day 21), an LHR test was performed on rat blood, and human basophils were sensitized with rat sera. HBA was demonstrated by the increase in the percentage of cells expressing CD63 antigen membrane, measured by flow cytometry. Twenty-one days after the first subcutaneous (s.c.) immunization, the rat serum induced a significant HBA. HBA was observed neither with the same serum previously heated nor with the serum from nonimmunized rats (NIRs). OVA-specific IgEs were significantly increased in immunized rat (IR) serum. The PCA test was negative when the serum was previously heated (56 degrees C). We never observed any circulating basophils, and LHR test was negative. After OVA i.v. administration, all IRs died rapidly. HBA testing strongly suggests a mediation by specific IgE in the increase of CD63 in BN rats. Thus, HBA test seems useful in assessing whether an experimental allergy was induced in animals genetically predisposed to an immune response, Th2-mediated, like BN rat. We also conclude that rat basophil activation does not participate in the histamine release during anaphylactic shock in sensitized BN rats.

Anaphylaxis↗
PubMed2002

Renal handling of salt and water in humans during exercise with or without hydration.

Plasma sodium (Na+) concentration, i.e. natraemia, results from body tonicity equilibrium. During exercise, a change in body tonicity can result from an imbalance between intake and loss of Na+, potassium (K+) and water (H2O) due to renal and/or extra-renal mechanisms. Whether exercise-induced changes in kidney function could be responsible for such an imbalance was studied by measuring glomerular filtration rate (creatinine clearance), proximal tubule activity (lithium clearance) and renal handling of Na+ and K+ at rest and during exercise. Since hyponatraemia during or after exercise has been reported, we also investigated whether a water load could be appropriately excreted during exercise. Ten young men pedalled on a cycle ergometer at 60% of maximal oxygen uptake for 45 min with (HE, hydrated exercise) or without (DHE, dehydrated exercise) a supply of water. In both conditions, creatinine, lithium, and electrolyte (Na+ + K+) clearances decreased and natraemia did not change. The DHE induced a loss of body mass (-1.29%), decreased diuresis and large extra-renal water loss [mean (SEM)] [880 (73) ml]. The HE led to no loss in body mass, increased diuresis and lower extrarenal water loss [680 (48) ml]. Electrolyte-free water excretion, negative for DHE, represented 60% of diuresis during HE. Thus the kidney, by increasing electrolyte reabsorption mainly in the proximal tubule, and appropriately excreting a water load, seems efficacious in regulating extracellular fluid volume and body tonicity and so not responsible for the imbalance between (Na+ + K+)/H2O intake and loss. Therefore, extra-renal changes could be the main causes of exercise-induced tonicity imbalances which could ultimately lead to dysnatraemia.

Adaptation, Physiological↗
PubMed2001

[A new concept to explain dysnatremia: the tonicity balance of entries and exits].

Plasma sodium concentration, or natremia, results from three main factors: exchangeable sodium (Na+), exchangeable potassium (K+) and total body water (H2O). Its alterations often imply a change in cell volume. Understanding dysnatremias is essential for the treatment and prevention of hydromineral disorders. Extra-cellular fluid tonomoles consist almost exclusively of Na+ salts. Their dilution is the tonicity. K+ is an essential tonomole for intra-cellular fluid tonicity. The balance between intra and extracellular tonicities depends on water movements and is responsible for changes in intra- and extracellular fluid volumes. Cell volume is therefore depending on the tonicity balance. A change in body tonicity (which is not osmolality) can be correctly and rapidly appreciated by measuring the (Na+ + K+) and H2O balances. Clinical cases emphasize the misleadings resulting from the free-water clearance calculation or the only measurements of urinary losses. They also demonstrate that tonicity balance provides indications for therapy whereas analyses based upon electrolyte-free water do not. Intakes should be quantified with the same care than losses. The units used must be coherent to allow a quick and easy understanding at the bedside. Tonicity balance should be taught and Na+ + K+ and H2O balances should be routinely utilized by practitioners, dieticians and nurses in the concerned pediatrics, in particular intensive care, internal medicine, nephrology, pediatry and anesthesiology.

Adolescent↗
PubMed1998

Variations in plasma sodium concentration in post-operative patients depend on an electrolyte-free water balance, part of a tonicity balance.

BACKGROUND: There is an inverse relationship between changes in the concentration of sodium in plasma (PNa) and intracellular fluid (ICF) volume. Intakes and losses of sodium (Na), potassium (K) and water can be divided into two volumes: isotonic and electrolyte-free water (EFW). Calculations of these volumes assess a tonicity balance, a tonicity imbalance results in a change of PNa: when EFW is added to body fluids, PNa decreases. Moreover, the concept of EFW permits a good understanding of the renal contribution to the defence of body tonicity. PURPOSE: To illustrate that the measurement of a tonicity balance provides the best estimate of changes in PNa in an ICU setting. METHODS: Twenty-two patients were admitted to the Post-Operative Intensive Care Unit. We investigated how well changes in EFW balance correlated with PNa variations and what is the best formula to calculate EFW in this setting. RESULTS: PNa changes depend on EFW balance; there is no significant relationship with other classical factors such as urinary osmolality or Na-free water. CONCLUSION: The utility of a tonicity balance is demonstrated. A formula is derived facilitating at the bedside the prediction of changes in PNa following fluid therapy: PNa2 = [(PNa1.TBW) + balance (Na + K)]/[TBW + balance H2O]. PNa changes can be understood and/or modified exclusively by a careful measurement of intakes and losses of Na, K and water.

Female↗
PubMed1998

[Hyponatremia, toward a logical approach: the balance of tonicity].

Derangements in plasma sodium concentration are best analyzed by carefully determining entries and output for water, sodium and potassium, that is, by calculating a tonicity balance. Five clinical hyponatremic examples are discussed: the beer drinker has a severe deficit in total body sodium: the elderly female patient treated with a thiazide needs to be firstly repleted in potassium; the hypertensive transplanted patient with a multidrug treatment requires an increase of the urinary electrolyte-free water which has been obtained by the oral administration of urea; the post-operative hyponatremic cases (cases 4 and 5) are complex and involve a desalination phenomenon. Close observation, repeated determinations of electrolytes in plasma, urine and entries, together with measurements of water input and output, will allow the tonicity balance of the patient to be understood and thus occasional tragedies such as observed in cases 4 and 5 to be prevented.

Adult↗
PubMed1994

Transplacental effects of gentamicin on endocytosis in rat renal proximal tubule cells.

Changes in kidney maturation in utero have been reported after gentamicin administration to pregnant rats. While the proteinuria commonly observed could be related to modifications of the glomerular basement membrane, perturbed renal protein handling could be accounted for by changes in the proximal tubular cells. Therefore, we studied the effect of gentamicin on the renal handling and transport of proteins in proximal tubular cells using the horseradish peroxidase, a fluid-phase marker, as a probe. Gentamicin was administered intraperitoneally to pregnant Wistar rats (75 mg/kg body weight per day) and neonatal kidneys were studied 1 day after birth. In proximal tubular cells of the deep cortical area, containing the fully matured nephrons of neonates, the transport and digestion of reabsorbed peroxidase was considerably reduced compared with controls where peroxidase reached lysosomes after endocytosis. Urinary protein excretion increased in treated animals. We conclude that gentamicin, entering the proximal tubular cells via the endocytic pathway, decreases the tubular reabsorption of proteins, thus increasing urinary protein excretion.

Animals↗
PubMed1994

[Central pontine myelinolysis: apropos of an oligosymptomatic form].

The authors report a case of paucisymptomatic central pontine myelinolysis (CMP). A 66 years old female had severe hypochloronatremia and hypokaliemia due to diuretic. Despite a slow hydroelectrolytic correction, she presented with dumbness and seizure. CT scan showed hypodensity of protuberance and magnetic resonance imaging (MRI) shown hypersignal of protuberance and undercortex, compatible with central and extra pontine myelinolysis. The long term clinical outcome was good, as MRI's data. Rapid and important correction of severe hyponatremia should be the most important factors of demyelination, secondary to interference with cerebral adaptation mechanisms to hypoosmolality. These factors were not present in this case.

Aged↗
PubMed1988

In utero aminoglycosides-induced nephrotoxicity in rat neonates.

Pregnant Wistar females were treated with gentamicin (G), netilmicin (N) or amikacin (A) during two periods of pregnancy covering organogenesis and the beginning of nephrogenesis. Deliveries occurred normally. We studied functional effects--influence of sex, litter size, diuresis, creatinine clearance, G-kidney concentration, and kidney morphological alterations--in rat neonates on day 1 of life. After G and N, the creatinine clearance of the neonates was decreased according to the dosage given to the mother. Whatever the aminoglycoside, kidneys presented proximal tubular alterations (close to those observed in adults) at protonic microscopy and, with electron microscopy, some modifications of distal tubules and of mature and immature glomeruli. It is concluded that the developing kidney can be altered after treating pregnant mothers with aminoglycosides. This model of in utero-induced nephrotoxicity is dose-dependent. Mature and/or immature structures could be affected. The toxicity of the investigated antibiotics could be asserted as G greater than or equal to N greater than A.

Amikacin↗
PubMed1986

In-utero gentamicin-induced nephrotoxicity in rats.

Aminosides lead to a well-known nephrotoxicity. The possibility of the developing kidney being altered in utero after the pregnant mother's administration has been investigated. We gave gentamicin (75 mg/kg/day) to pregnant rats during periods of organogenesis (days 7-11) and the beginning of glomeruli differentiation (days 14-18). A group of nonpregnant females was also treated for the same period and at the same time each day. Gentamicin-treated mothers presented only minor modifications of the blood biology with no acute renal failure when treated nonpregnant females have a hypercreatininemia. The deep cortical area, containing the fully formed nephrons of neonates, presented less glomeruli that were differentiated in the gentamicin group than in the control group. Moreover with both light and electron microscopy, glomeruli and proximal tubules showed evidences of nephrotoxicity in the juxtamedullary cortex. This finding of an in utero aminoside nephrotoxicity demonstrates the possible toxicity of gentamicin on fetus kidneys when given during the pregnancy.

Abnormalities, Drug-Induced↗
PubMed1975

[Study of the criteria of evaluation of the exercise capacity of the chronic hemodialyzed subject].

Direct measurement methods (or the forecast related to indirect measurements) of the maximal oxygen uptake are reviewed. 15 patients suffering from renal failure, performed a total of 28 exercises. One can draw the conclusion that the maximum VO2 is inferior in these subjects to the values usually determined in normal healthy subjects of the same age. This decrease can be significantly correlated with the haematocrit. Comparison between direct measurement methods of the maximal oxygen uptake and indirect methods allowing its forecast from the heart rate, shows that only direct methods are to be used in these patients.

Adult↗