The oligosaccharide needed for protein N-glycosylation is assembled on a lipid carrier via a multistep pathway. Synthesis is initiated on the cytoplasmic face of the endoplasmic reticulum (ER) and completed on the luminal side after transbilayer translocation of a heptasaccharide lipid intermediate. More than 30 congenital disorders of glycosylation (CDGs) are associated with this pathway, including RFT1-CDG which results from defects in the membrane protein Rft1.
View Article and Find Full Text PDFThe oligosaccharide needed for protein -glycosylation is assembled on a lipid carrier via a multi-step pathway. Synthesis is initiated on the cytoplasmic face of the endoplasmic reticulum (ER) and completed on the luminal side after transbilayer translocation of a heptasaccharide lipid intermediate. More than 30 Congenital Disorders of Glycosylation (CDGs) are associated with this pathway, including RFT1-CDG which results from defects in the membrane protein Rft1.
View Article and Find Full Text PDFClass A G protein-coupled receptors (GPCRs), a superfamily of cell membrane signaling receptors, moonlight as constitutively active phospholipid scramblases. The plasma membrane of metazoan cells is replete with GPCRs yet has a strong resting trans-bilayer phospholipid asymmetry, with the signaling lipid phosphatidylserine confined to the cytoplasmic leaflet. To account for the persistence of this lipid asymmetry in the presence of GPCR scramblases, we hypothesized that GPCR-mediated lipid scrambling is regulated by cholesterol, a major constituent of the plasma membrane.
View Article and Find Full Text PDFClass A G protein-coupled receptors (GPCRs), a superfamily of cell membrane signaling receptors, moonlight as constitutively active phospholipid scramblases. The plasma membrane of metazoan cells is replete with GPCRs, yet has a strong resting trans-bilayer phospholipid asymmetry, with the signaling lipid phosphatidylserine confined to the cytoplasmic leaflet. To account for the persistence of this lipid asymmetry in the presence of GPCR scramblases, we hypothesized that GPCR-mediated lipid scrambling is regulated by cholesterol, a major constituent of the plasma membrane.
View Article and Find Full Text PDFBackground: is an oleo gum resin obtained from the plant (Arn.) Bhand., used in medicines for various ailments like anti-inflammatory conditions, hyperlipidemia, thyroid disorders etc.
View Article and Find Full Text PDFObjective: Tumour necrosis factor α inhibitors (TNFis) are widely used in RA patients who undergo surgery, and optimal perioperative management must balance the risk of infection with the risk of post-operative flare. The purpose of this study is to examine the impact of TNFi exposure on surgical site infections (SSIs) in RA patients undergoing elective orthopaedic surgery by systematic review and meta-analysis.
Methods: A systematic review of the literature and meta-analysis were performed using PUBMED, EMBASE and the Cochrane Central Register of Controlled Trials, through May 2014.
Opsin, the rhodopsin apoprotein, was recently shown to be an ATP-independent flippase (or scramblase) that equilibrates phospholipids across photoreceptor disc membranes in mammalian retina, a process required for disc homoeostasis. Here we show that scrambling is a constitutive activity of rhodopsin, distinct from its light-sensing function. Upon reconstitution into vesicles, discrete conformational states of the protein (rhodopsin, a metarhodopsin II-mimic, and two forms of opsin) facilitated rapid (>10,000 phospholipids per protein per second) scrambling of phospholipid probes.
View Article and Find Full Text PDFBackground: Social networking is seen as a way to enhance social support and feeling of well-being. The present work explores the potentials of social networking sites as an adjunctive treatment modality for initiating treatment contact as well as for managing psychological problems.
Materials And Methods: Interview schedule, Facebook intensity questionnaire were administered on 28 subjects with a combination of 18 males and 10 females.
Synapses continually replenish their synaptic vesicle (SV) pools while suppressing spontaneous fusion events, thus maintaining a high dynamic range in response to physiological stimuli. The presynaptic protein complexin can both promote and inhibit fusion through interactions between its α-helical domain and the SNARE complex. In addition, complexin's C-terminal half is required for the inhibition of spontaneous fusion in worm, fly, and mouse, although the molecular mechanism remains unexplained.
View Article and Find Full Text PDFMost glycosphingolipids are synthesized by the sequential addition of monosaccharides to glucosylceramide (GlcCer) in the lumen of the Golgi apparatus. Because GlcCer is synthesized on the cytoplasmic face of Golgi membranes, it must be flipped to the non-cytoplasmic face by a lipid flippase in order to nucleate glycosphingolipid synthesis. Halter et al.
View Article and Find Full Text PDFPolar lipids must flip-flop rapidly across biological membranes to sustain cellular life [1, 2], but flipping is energetically costly [3] and its intrinsic rate is low. To overcome this problem, cells have membrane proteins that function as lipid transporters (flippases) to accelerate flipping to a physiologically relevant rate. Flippases that operate at the plasma membrane of eukaryotes, coupling ATP hydrolysis to unidirectional lipid flipping, have been defined at a molecular level [2].
View Article and Find Full Text PDFBased on a nationally representive household survey of Kuwaiti women held in 1999 (n = 1502) unmet need for contraception was analyzed in Kuwait, an oil-rich Muslim country. It was found that 9.7% currently married women had an unmet need for contraception.
View Article and Find Full Text PDFThe main objectives of this article are to analyze the correlates of living arrangements of persons aged 60 or above in the oil-rich, Muslim country of Kuwait and to examine whether or not patterns of co-residence differ by gender. Data were obtained from a nationally representative survey of households of Kuwaiti nationals, and this paper is based on the 687 older Kuwaiti residents of these households. Living arrangements were generally similar for women and men.
View Article and Find Full Text PDFBackground: Rhinovirus (RV) infections can result in asthma exacerbations in both adults and children. Respiratory epithelium, the primary site of RV replication, responds to the viral infection by generating a variety of cytokines and chemokines capable of promoting airway inflammation and hence might increase asthma severity. Some of these mediators might also affect the permeability of underlying vascular endothelium.
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