Crosslinking and depletion determine spatial instabilities in cytoskeletal active matter.

Active gels made of cytoskeletal proteins are valuable materials with attractive non-equilibrium properties such as spatial self-organization and self-propulsion. At least four typical routes to spatial patterning have been reported to date in different types of cytoskeletal active gels: bending and buckling instabilities in extensile systems, and global and local contraction instabilities in contractile gels. Here we report the observation of these four instabilities in a single type of active gel and we show that they are controlled by two parameters: the concentrations of ATP and depletion agent.

Effect of age, stress and protein supply on plasma amino acids during continuous enteral nutrition; a pragmatic study in rats.

Background & Aims: As life expectancy increases, an increasing older population may require surgery with perioperative nutritional management. While little is known about the combined effect of age and stress on amino acid metabolism during enteral nutrition, we hypothesized that blood amino acid bioavailability may be influenced not only by the characteristics of the ingested protein but also by intestinal ageing and splanchnic sequestration of amino acids. Plasma amino acid kinetics were thus evaluated in aged and adult rats receiving continuous enteral nutrition before and after standardized surgical stress.

Effect of aging on the availability of amino acids from an immune-enhancing diet (IED) after a surgical stress in rats.

Background & Aims: Dietary amino acid (AA) requirements increase after a surgical stress while the systemic AA availability from the diet decreases with age, due to splanchnic sequestration. While immune-enhancing diets (IEDs) have been recommended for the nutritional management of surgical patients, the systemic bioavailability of their AA supply has not been evaluated in elderly surgical patients. This was determined in surgically-stressed IED-fed aged rats.

Influence of an ω3-fatty acid-enriched enteral diet with and without added glutamine on the metabolic response to injury in a rat model of prolonged acute catabolism.

Objective: In critically ill patients, acute injury alters gut function, causing greater risk for sepsis and malnutrition. Peptide-enriched diets may promote nitrogen absorption, whereas ω3-enriched diets reduce alterations in gut barrier function. The aim of this study was to assess the effectiveness of a peptide- and ω3-enriched diet on the metabolic response to injury and the gut barrier function in a model of prolonged catabolism in the rat.

Estimation of glomerular filtration rate in cancer patients with abnormal body composition and relation with carboplatin toxicity.

Purpose: Carboplatin clearance is correlated with glomerular filtration rate (GFR) and usually estimated with creatinine clearance using Cockcroft-Gault (CG) formula. Because plasma creatinine level is highly correlated with muscle mass, we hypothesized that an abnormal body composition with a low lean body mass (LBM) percentage [(LBM/weight) × 100] may result in inadequate carboplatin dosing. Serum cystatin C is an alternative marker of GFR, not affected by muscle mass.

Citrulline and Nonessential Amino Acids Prevent Fructose-Induced Nonalcoholic Fatty Liver Disease in Rats.

Background: Fructose induces nonalcoholic fatty liver disease (NAFLD). Citrulline (Cit) may exert a beneficial effect on steatosis.

Objective: We compared the effects of Cit and an isonitrogenous mixture of nonessential amino acids (NEAAs) on fructose-induced NAFLD.

Diagnosis of Iron Deficiency in Inflammatory Bowel Disease by Transferrin Receptor-Ferritin Index.

Iron deficiency is common in patients with inflammatory bowel disease (IBD), but can be difficult to diagnose in the presence of inflammation because ferritin is an acute phase reactant. The transferrin receptor-ferritin index (TfR-F) has a high sensitivity and specificity for iron deficiency diagnosis in chronic diseases. The diagnostic efficacy of TfR-F is little known in patients with IBD.

Effect of specific amino acids on hepatic lipid metabolism in fructose-induced non-alcoholic fatty liver disease.

Background & Aim: Fructose diets have been shown to induce insulin resistance and to alter liver metabolism and gut barrier function, ultimately leading to non-alcoholic fatty liver disease. Citrulline, Glutamine and Arginine may improve insulin sensitivity and have beneficial effects on gut trophicity. Our aim was to evaluate their effects on liver and gut functions in a rat model of fructose-induced non-alcoholic fatty liver disease.

Early chloride intake does not parallel that of sodium in extremely-low-birth-weight infants and may impair neonatal outcomes.

Background And Objective: Accurate data on the optimal chloride (Cl) intake in premature infants are scarce. The aim of the present study was to describe Cl intakes in the first 10 days of life and to assess the relations between high Cl intakes and corrected serum Cl level or markers of severe acidosis in infants <28 weeks' gestation.

Methods: Retrospective cohort study including all of the infants <28 weeks admitted to the neonatal intensive care unit during a 3-year period and cared for from birth until day 10 or more.

Targeting of polymeric nanoparticles to lung metastases by surface-attachment of YIGSR peptide from laminin.

Effective therapy for disseminated metastatic cancer is currently impossible because of low drug accumulation in target sites. Here, we aimed to enhance nanoparticle (NP) targeting to lung melanoma metastases via interactions with the laminin receptor, whose expression is upregulated in metastatic cells. To enable NP follow-up and a framework for targeting ligand binding, Estapor(®) fluorescent NPs (299 ± 6 nm in diameter) with surface carboxylic groups were employed and the laminin receptor binding peptide (YIGSR) was attached to their surface to facilitate targeting.

Photochemical attachment of biomolecules onto fibre-optics for construction of a chemiluminescent immunosensor.

We report herein a simple and effective way to photochemically immobilize biomolecules onto a fibre-optic silica surface. The system is based on a photoreactive benzophenone derivative that is bound to SiO2 surfaces of the optical fibre via a silane anchor. The benzophenone derivative was 4-allyloxybenzophenone, synthesized by standard procedures that were later used to synthesize the 4-(3'-chlorodimethylsilyl) propyloxybenzophenone and 4-(3'-dichloromethylsilyl) propyloxybenzophenone by regular hydrosilation procedures.

Effect of piracetam on polyphosphoinositide metabolism, cytosolic calcium release, and oxidative burst in human polymorphonuclear cells: interaction with fMLP-induced stimulation.

We investigated the action of piracetam on human polymorphonuclear leukocyte (PMN) responsiveness in vitro. We first studied phosphoinositide metabolism and calcium release with and without fMLP (formyl-methionyl-leucyl-phenylalanine) stimulation. Piracetam at concentrations from 10(-4) to 10(-2) M induced a slight increase in inositol 1,4,5-trisphosphate (IP3) release and phosphatidylinositol 4,5-bisphosphate (PIP2) breakdown.

Dermaseptin, a peptide antibiotic, stimulates microbicidal activities of polymorphonuclear leukocytes.

Dermaseptin (DRs S1), a 34-amino acid residue cationic antimicrobial peptide was studied for its effects on the production of reactive oxygen species (respiratory burst) and exocytosis of polymorphonuclear leukocytes (PMN). Treatment of PMN with DRs S1 (10-100 nM) stimulated significant production of reactive oxygen species (approximately a 2-fold increase relative to control) and release of myeloperoxidase. In addition, low DRs S1 concentrations (1-10 nM) primed the stimulation of respiratory burst induced by zymosan particles.

Effect of encapsulation on the anti-inflammatory properties of superoxide dismutase after oral administration.

Anti-inflammatory properties of free superoxide dismutase and superoxide dismutase encapsulated into liposomes, with or without ceramides, have been investigated. Two models were investigated: carrageenan paw oedema and pleurisy. Animals were fed by repeated doses, twice daily from day 1 until day 4.

Liver metastases: safety and efficacy of detection with superparamagnetic iron oxide in MR imaging.

Purpose: To evaluate the clinical and biologic safety of superparamagnetic iron oxide (SPIO) as a contrast agent in magnetic resonance (MR) imaging and to assess its efficacy in the detection of liver metastases.

Materials And Methods: Twenty adults with liver metastases underwent MR imaging at 1.5 T before and 1 hour after infusion of SPIO.

In vitro effect of cetirizine on PGE2 release by rat peritoneal macrophages and human monocytes.

Cetirizine was first described as a specific anti-H1 molecule displaying potent antiallergic activity. It was later found that its pharmacological properties extended to cellular actions as on eosinophil recruitment at inflammatory sites in allergic patients. Monocytes and macrophages participate in allergic mechanisms, particularly through high affinity H1 and H2 membrane receptors and generation of pro- and anti-inflammatory agents; among them histamine-induced factors, IL-1 and prostanoids are of importance.

Comparative effects of F1 and P1 fractions obtained from a Klebsiella pneumoniae glycoproteic extract (RU 41740) on polymorphonuclear leukocytes.

RU 41740 is a glycoprotein extract from Klebsiella pneumoniae described as a macromolecular aggregation of a lipopolysaccharide (LPS)-associated protein (F1 fraction) and a glycoproteic complex (P1 fraction). The human polymorphonuclear (PMN) response was studied after incubation of the cells in the presence of RU 41740, F1 and P1 fractions, or F1-P1 complex. Oxidative metabolism was assessed by chemiluminescence, O2 consumption, O2- generation, and degranulation by beta-glucuronidase release.

[Surgery of primary hyperparathyroidism. Contribution of the peroperative assay of urinary cyclic AMP].

The increase of nephrogenic cyclic AMP is an excellent index of parathyroid hypersecretion. A successful treatment of primary hyperparathyroidism results in a rapid fall in nephrogenic cAMP. In a series of 24 patients with proven primary hyperparathyroidism (hyperplasia 3, adenoma 21) and 2 patients with suspected hyperparathyroidism, the success of surgical excision was evaluated by measuring the urinary cAMP/urinary creatinine ratio (R), which in the absence of renal impairment, is proportional to the level of nephrogenic cAMP.

Superoxide dismutases in polymorphonuclear leukocytes from patients with ankylosing spondylitis or rheumatoid arthritis.

The activity of cyanide-sensitive and cyanide-insensitive superoxide dismutase (CNs- and CNi-SOD) was measured in polymorphonuclear neutrophils isolated from the blood of patients with ankylosing spondylitis (A.S.) or adults with rheumatoid arthritis (R.

Manganese-containing superoxide-dismutase deficiency in polymorphonuclear leukocytes of adults with rheumatoid arthritis.

Superoxide dismutase (SOD) is known to regulate the level of superoxide radicals inside cells. The purpose of this work was to investigate the role of SOD activity in tissue damage produced by superoxide radicals. SOD was measured in polymorphonuclear cells of patients with rheumatoid arthritis and controls.

[Role of membrane sialic acid of human granulocytes in the stimulation of NADPH,H+ oxidase activity].

The treatment of human polymorphonuclear cells by neuraminidase "type-X" removes about 15% of cell sialic acid without modifications of NADPH oxidase activity of granulocytes before and after stimulation by opsonized zymosan. A mild periodate treatment oxidizes only the poly-hydroxilic chain of sialic acid with formation of aldehyde groups. This treatment increases cellular NADPH oxidase activity and also largely prevents the stimulation of polymorphonuclear cells by opsonized zymosan.

Action of a polysaccharide fraction of Haemophilus influenzae lipopolysaccharide on macrophage: implication of receptor for mannosyl-polysaccharides.

A polysaccharide fraction (PS) was separated by mild hydrolysis from Haemophilus influenzae lipopolysaccharide. This preparation contained glycosyl-galactosyl, rhamnosyl, glucosaminyl and mannosyl residues (molar ratio: 4-1-1-2-2). It was nontoxic and immunogenic and consisted of at least one stable molecular group (fraction A; MW approximately equal to 10(6)) and an association of aggregated units (fraction B;MW approximately equal to 10(4)).

[A colorimetric method for the evaluation of phagocytosis by mouse peritoneal macrophages (author's transl)].

In this study, a technique for the evaluation of circulating leukocyte phagocytosis has been adapted to mouse peritoneal macrophages. This quantitative determination was performed by the spectrophotometric measurement of the reduced nitroblue tetrazolium (NBT) fixed on bacteria or latex spherules. Capacity of phagocytosis was thus correlated with the intensity of the NBT intracellular reduction by macrophages.