Search results for "Lipids"

Ink depletion-free printing of phospholipids micropatches

2021

Effect of an insect growth regulator (halofenozide) on the cuticular hydrocarbons of Culex pipiens larvae

2013

The cuticular hydrocarbons of the fourth-instar larvae of Culex pipiens aged one and six days were analysed by gas chromatography and gas chromatography-mass spectrometry. The effect of an insect growth regulator (halofenozide = RH-0345) on the cuticular hydrocarbons was evaluated using newly moulted fourth-instar larvae of C. pipiens, at the lethal concentrations (LC50 = 12.58 and LC90 = 28.58 mu g/l). A previous study revealed that RH-0345 is toxic to larvae of C. pipiens by induction of precocious larval moulting. Several cuticular hydrocarbons (CHCs) were identified and many of the other compounds remained unknown. Our data show that the CHC classes consisted of n-alkanes (C23-C29) and …

“Anything taking shape?” : Capturing various layers of small group collaborative problem solving in an experiential geometry course in initial teache…

2022

Collaborative problem solving (CPS) is widely recognized as a prominent 21st-century skill to be mastered. Until recently, research on CPS has often focused on problem solution by the individual; the interest in investigating how the theorized problem-solving constructs function as broader social units, such as pairs or small groups, is relatively recent. Capturing the complexity of CPS processes in group-level interaction is challenging. Therefore, a method of analysis capturing various layers of CPS was developed that aimed for a deeper understanding of CPS as a small-group enactment. In the study, small groups of teacher education students worked on two variations of open-ended CPS tasks…

Prostaglandin E2 and prostaglandin F2 alpha as endometrial receptivity biomarkers in successful embryo implantation

2014

Failure in the adhesion of the human blastocyst to the endometrium has been described as an important cause of infertility. Establishing the period of the so-called window of implantation and understanding the molecular mechanisms associated with embryo implantation has clinical and scientific implications. While over the last decades histological evaluation has been used to determine the phase of the menstrual cycle of the endometrium, the poor information obtained has made the case of using new technologies to identify specific markers, understand and characterize the receptive stage. This doctoral thesis investigates the existence, function and clinical impact of two specific lipids, the…

Transport of Arabidopsis GPI-anchored proteins along the early secretory pathway: Role of GPI-anchor remodelling and p24 proteins

2019

Las proteínas con anclaje GPI son una familia de proteínas que están ancladas a la cara exterior de la membrana plasmática mediante un ancla GPI y se ha visto que juegan un papel clave en plantas. Sin embargo, la maquinaria molecular implicada en el transporte de estas proteínas a la membrana plasmática en plantas es aún desconocida. Las proteínas p24 tienen un papel importante en el control de calidad de proteínas (posiblemente incluyendo las proteínas con anclaje GPI) transportadas entre el Retículo Endoplasmático y el aparato de Golgi. Esta tesis doctoral tiene como objetivo el estudio de la posible implicación de las proteínas p24 en la salida del Retículo Endoplasmático y en la localiz…

Exploring fast proton transfer events associated with lateral proton diffusion on the surface of membranes

2019

Proton diffusion (PD) across biological membranes is a fundamental process in many biological systems, and much experimental and theoretical effort has been employed for deciphering it. Here, we report on a spectroscopic probe, which can be tightly tethered to the membrane, for following fast (nanosecond) proton transfer events on the surface of membranes. Our probe is composed of a photoacid that serves as our light-induced proton source for the initiation of the PD process. We use our probe to follow PD, and its pH dependence, on the surface of lipid vesicles composed of a zwitterionic headgroup, a negative headgroup, a headgroup that is composed only from the negative phosphate group, or…

RAB18 Loss Interferes With Lipid Droplet Catabolism and Provokes Autophagy Network Adaptations

2020

Autophagy is dependent on appropriate lipid supply for autophagosome formation. The regulation of lipid acquisition and the autophagy network response to lipid-limiting conditions are mostly elusive. Here, we show that the knockout of the RAB GTPase RAB18 interferes with lipid droplet catabolism, causing an impaired fatty acid release. The resulting reduced lipid-droplet-derived lipid availability influences autophagy and provokes adaptive modifications of the autophagy network. These adjustments include increased expression and phosphorylation of ATG2B as well as augmented formation of the ATG12-ATG5 conjugate. Moreover, ATG9A shows an enhanced phosphorylation at amino acid residues tyrosi…

Inhibition of Rac1 signaling by lovastatin protects against anthracycline-induced cardiac toxicity

2011

Normal tissue damage limits the efficacy of anticancer therapy. For anthracyclines, the clinically most relevant adverse effect is cardiotoxicity. The mechanisms involved are poorly understood and putative cardioprotectants are controversially discussed. Here, we show that the lipid-lowering drug lovastatin protects rat H9c2 cardiomyoblasts from doxorubicin in vitro. Protection by lovastatin is related to inhibition of the Ras-homologous GTPase Rac1. It rests on a reduced formation of DNA double-strand breaks, resulting from the inhibition of topoisomerase II by doxorubicin. Doxorubicin transport and reactive oxygen species are not involved. Protection by lovastatin was confirmed in vivo. I…

Enterobacter cloacae administration induces hepatic damage and subcutaneous fat accumulation in high-fat diet fed mice.

2018

Accumulating evidence indicates that gut microbiota plays a significant role in obesity, insulin resistance and associated liver disorders. Family Enterobacteriaceae and especially Enterobacter cloacae strain B29 have been previously linked to obesity and hepatic damage. The underlying mechanisms, however, remain unclear. Therefore, we comprehensively examined the effects of E. cloacae subsp. cloacae (ATCC® 13047™) administration on host metabolism of mice fed with high-fat diet (HFD). C57BL/6N mice were randomly divided into HFD control, chow control, and E. cloacae treatment groups. The E. cloacae treatment group received live bacterial cells in PBS intragastrically twice a week, every ot…

Dietary fatty acids in the retina: beyond DHA, is EPA the underestimate intermediate?

2016

Dietary fatty acids in the retina: beyond DHA, is EPA the underestimate intermediate?. 12. congress of the international society for the study of fatty acids and lipids