Dipeptiven® is safe in a rat model of moderate liver dysfunction

Summary: Background & aims: Administration of glutamine in patients with liver failure is thought to possibly increase blood ammonia levels, thereby contributing to hepatic encephalopathy. In a rat model of moderate liver dysfunction with elevated plasma glutamine concentrations dose-dependent effects of intravenous alanyl-glutamine infusion on possible biochemical and histological signs of toxicity were investigated. Methods: Rats with moderate liver dysfunction resulting from alpha-naphthylisothiocyanate (ANIT) induced cholestasis received a 9 days continuous intravenous infusion of 0.5 g/kg/day or 3.0 g/kg/day alanyl-glutamine (Dipeptiven®). Dose-dependent effects on liver injury were assessed by analyzing blood levels of ammonia, urea, ALT, AST, and ALP, glutamine, and histopathology. Results: Continuous intravenous infusion of 3.0 g/kg/day alanyl-glutamine increased plasma glutamine concentrations up to 30% without increasing blood ammonia levels or inducing astrocyte swelling. Alanyl-glutamine did not aggravate underlying liver injury shown by absent increase in plasma levels of ALT, AST, ALP and no signs of histopathologic alterations. Conclusions: Continuous intravenous infusion of alanyl-glutamine at 0.5 and 3.0 g/kg/day up to 9 consecutive days is safe in a rat model of moderate liver dysfunction based on ANIT-induced cholestasis. Keywords: Ammonia, Astrocyte swelling, Brain edema, Cholestasis, Glutamine, Liver injur

Missing evidence for toxicity of high PFAT5 levels in mixtures of lipids

Background: The compliance of lipid admixtures to physical emulsion stability parameters is extremely important to ensure the safety of patients. For example, admixtures containing a percentage of fat globules larger than 5 μm in diameter (concept known as PFAT5) of more than 0.05% might produce toxic effects in lung and liver. This concern is mainly based on a limited number of animal studies investigating admixtures with high PFAT5 levels resulting from 48 h of admixture storage. However, all effects observed in these studies might as well be attributed to chemical instability like lipid oxidation, which was not analysed and therefore could not be excluded. Aims: This study aims at investigating the correlation of high levels of PFAT5 in lipid emulsion admixtures with lipid oxidation parameters under different storage conditions. Methods: We studied the physical (PFAT5 value) as well as the chemical (pH, primary and secondary oxidation parameters) stability of an admixture of a lipid emulsion and an amino acid solution after up to 48 h following different storage conditions (exposure to oxygen, exposure to artificial light). Results: High levels of PFAT5 were only observed after exposure of the admixture to oxygen. Additional exposure to artificial light led to a parallel increase in the primary and secondary oxidation parameters, while the pH was unchanged. Conclusions: The admixtures investigated in the former animal studies were obviously both physically and chemically unstable and all effects observed in the studies could just as well be caused by chemical instability, namely the administration of lipid peroxides with the admixture

Dose-Dependent Prebiotic Effect of Lactulose in a Computer-Controlled In Vitro Model of the Human Large Intestine

Lactulose, a disaccharide of galactose and fructose, used as a laxative or ammonia-lowering drug and as a functional food ingredient, enhances growth of Bifidobacterium and Lactobacillus at clinically relevant dosages. The prebiotic effect of subclinical dosages of Lactulose, however, remains to be elucidated. This study analyses changes in the microbiota and their metabolites after a 5 days Lactulose treatment using the TIM-2 system, a computer-controlled model of the proximal large intestine representing a complex, high density, metabolically active, anaerobic microbiota of human origin. Subclinical dosages of 2–5 g Lactulose were used. While 2 g Lactulose already increased the short-chain fatty acid levels of the intestinal content, 5 g Lactulose were required daily for 5 days in this study to exert the full beneficial prebiotic effect consisting of higher bacterial counts of Bifidobacterium, Lactobacillus, and Anaerostipes, a rise in acetate, butyrate and lactate, as well as a decrease in branched-chain fatty acids, pH (suggested by an increase in NaOH usage), and ammonia

The use of reinforcement learning algorithms to meet the challenges of an artificial pancreas

Blood glucose control, for example, in diabetes mellitus or severe illness, requires strict adherence to a protocol of food, insulin administration and exercise personalized to each patient. An artificial pancreas for automated treatment could boost quality of glucose control and patients' independence. The components required for an artificial pancreas are: i) continuous glucose monitoring (CGM), ii) smart controllers and iii) insulin pumps delivering the optimal amount of insulin. In recent years, medical devices for CGM and insulin administration have undergone rapid progression and are now commercially available. Yet, clinically available devices still require regular patients' or caregivers' attention as they operate in open-loop control with frequent user intervention. Dosage-calculating algorithms are currently being studied in intensive care patients [1] , for short overnight control to supplement conventional insulin delivery [2] , and for short periods where patients rest and follow a prescribed food regime [3] . Fully automated algorithms that can respond to the varying activity levels seen in outpatients, with unpredictable and unreported food intake, and which provide the necessary personalized control for individuals is currently beyond the state-of-the-art. Here, we review and discuss reinforcement learning algorithms, controlling insulin in a closed-loop to provide individual insulin dosing regimens that are reactive to the immediate needs of the patient

The genome of the kinetoplastid parasite, Leishmania major

Leishmania species cause a spectrum of human diseases in tropical and subtropical regions of the world. We have sequenced the 36 chromosomes of the 32.8-megabase haploid genome of Leishmania major (Friedlin strain) and predict 911 RNA genes, 39 pseudogenes, and 8272 protein-coding genes, of which 36% can be ascribed a putative function. These include genes involved in host-pathogen interactions, such as proteolytic enzymes, and extensive machinery for synthesis of complex surface glycoconjugates. The organization of protein-coding genes into long, strand-specific, polycistronic clusters and lack of general transcription factors in the L. major, Trypanosoma brucei, and Trypanosoma cruzi (Tritryp) genomes suggest that the mechanisms regulating RNA polymerase II–directed transcription are distinct from those operating in other eukaryotes, although the trypanosomatids appear capable of chromatin remodeling. Abundant RNA-binding proteins are encoded in the Tritryp genomes, consistent with active posttranscriptional regulation of gen