Search Results
Results 151 - 200 of 2421
1 2 3 4 5 6 7 8 9 10 >
del Amo Eva M - - 2008
LAT1 and LAT2 are heterodimeric large amino acid transporters that are expressed in various tissues, including the intestinal wall, blood-brain barrier, and kidney. These transporters consist of membrane spanning light chain and heavy chain, and they act as 1:1 exchangers in concert with other amino acid transporters. Only a few ...
Nakagawa Hatsuki - - 2008
Perfluorooctanoic acid, an environmental contaminant, is found in both wild animals and human beings. There are large species and sex differences in the renal excretion of perfluorooctanoic acid. In the present study, we aimed to characterize organic anion transporters 1-3 (OAT1-3) in human beings and rats to investigate whether the ...
Katragadda Suresh S Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 5005 Rockhill Road, Kansas City, MO 64110-2499, - - 2008
In vivo systemic absorption of the amino acid prodrugs of acyclovir (ACV) after oral administration was evaluated in rats. Stability of the prodrugs, L-alanine-ACV (AACV), L-serine-ACV (SACV), L-isoleucine-ACV (IACV), gamma-glutamate-ACV (EACV) and L-valine-ACV (VACV) was evaluated in various tissues. Interaction of these prodrugs with the transporters on Caco-2 cells was ...
Talluri Ravi S RS Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 5005 Rockhill Road Kansas City, Missouri 64110-2499, - - 2008
The objective of this study was to synthesize and evaluate novel enzymatically stable dipeptide prodrugs for improved absorption of acyclovir. l-Valine-l-valine-acyclovir (LLACV), l-valine-d-valine-acyclovir (LDACV), d-valine-l-valine-acyclovir (DLACV) and d-valine-d-valine-acyclovir (DDACV) were successfully synthesized. The uptake and transport studies were conducted on a Caco-2 cell line. Buffer stability and metabolism of the ...
Larsen Mie - - 2008
The objective of this study was to investigate transepithelial amino acid transport as a function of Caco-2 cell culture time. Furthermore, the objective was to investigate apical uptake characteristics of hPAT1-mediated transport under various experimental conditions. Apical amino acid uptake and transport studies were conducted in Caco-2 monolayers cultured for ...
Sandoval Angel - - 2008
These studies defined the expression patterns of genes involved in fatty acid transport, activation and trafficking using quantitative PCR (qPCR) and established the kinetic constants of fatty acid transport in an effort to define whether vectorial acylation represents a common mechanism in different cell types (3T3-L1 fibroblasts and adipocytes, Caco-2 ...
Nagashima Akitomo - - 2008
N-1-Naphthylphthalamic acid (NPA) causes the abnormal growth and development of plants by suppressing polar auxin transport. The mechanisms underlying this inhibition, however, have remained elusive. In Arabidopsis, we show that a defect in the ABC subfamily B auxin transporter AtABCB19 suppresses the inhibitory effects of NPA on hypocotyl phototropism and ...
Koljonen Maija - - 2008
The purpose of this study was to evaluate passive vs. proton-dependent active transport mechanisms of salicylic acid (SA) and four structurally related anions. Transport was studied across Caco-2 cell monolayers and artificial lipid membranes (PAMPA) under pH-gradient and iso-pH conditions. Kinetic permeability parameters were provided by bidirectional Caco-2 experiments and ...
Oppedisano Francesca - - 2008
Na+ dependent [3H]glutamine uptake was found in liposomes reconstituted with solubilized rat kidney brush border in the presence of intraliposomal K+. The reconstituted system was optimised with respect to the critical parameters of the cyclic detergent removal procedure, i.e., the detergent used for the solubilization, the protein concentration, the detergent/phospholipid ...
Boina Dhana Raj - - 2008
BACKGROUND: Because methyl bromide has been phased out as a soil sterilant, new nematicides are urgently needed. Four different chemical classes of organic acids acting as anion transport (AT) blockers were tested against a free-living nematode, Caenorhabditis elegans Maupas, a plant-parasitic nematode, Meloidogyne incognita (Kofoid and White) Chitwood, and an ...
Hussainzada Naissan - - 2008
Functional contributions of residues Val-99-Ser-126 lining extracellular loop (EL) 1 of the apical sodium-dependent bile acid transporter were determined via cysteine-scanning mutagenesis, thiol modification, and in silico interpretation. Despite membrane expression for all but three constructs (S112C, Y117C, S126C), most EL1 mutants (64%) were inactivated by cysteine mutation, suggesting a ...
Fei Hao H Departments of Psychiatry and Neurobiology, Gonda Goldschmied Neuroscience and Genetics Research Center, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095-1761, - - 2008
Vesicular neurotransmitter transporters are required for the storage of all classical and amino acid neurotransmitters in secretory vesicles. Transporter expression can influence neurotransmitter storage and release, and trafficking targets the transporters to different types of secretory vesicles. Vesicular transporters traffic to synaptic vesicles (SVs) as well as large dense core ...
Okech Bernard A BA The Whitney Laboratory for Marine Bioscience, University of Florida, 9505 Ocean Shore Boulevard, St Augustine, FL 3208, - - 2008
The nutrient amino acid transporter (NAT) subfamily is the largest subdivision of the sodium neurotransmitter symporter family (SNF; also known as SLC6; HUGO). There are seven members of the NAT population in the African malaria mosquito Anopheles gambiae, two of which, AgNAT6 and AgNAT8, preferably transport indole- and phenyl-branched substrates, ...
Yoshida Naoko - - 2008
The possibility of interactions between natural products/supplements and conventional prescription medicines is one of the most important issues in pharmacotherapeutic safety. Recently, we reported that some terpenoids such as (R)-(+)-citronellal and glycyrrhetic acid, which are present in herbal medicines, can act as inhibitors of P-glycoprotein (MDR1/ABCB1). In the present study, ...
Sebastianelli Luca - - 2008
It is not yet clear how L-dopa, that is the most effective drug for the treatment of Parkinson's disease, enters into the dopaminergic neurons to be transformed into dopamine. It is suggested that L-dopa is mainly transported into cells by a group of L-amino acid carriers named "System L". Since ...
Inoue Koji - - 2008
Various invertebrates inhabiting hydrothermal vents possess sulfur-oxidizing bacteria in their tissues; however, the mechanisms by which toxic sulfides are delivered to these endosymbionts remain unknown. Recently, detoxification of sulfides using thiotaurine, a sulfur-containing amino acid, has been suggested. In this study, we propose the involvement of a taurine transporter in ...
Sagné C - - 2008
In contrast to lysosomal hydrolytic enzymes, the lysosomal membrane remains poorly characterized. In particular, although the genetic study of cystinosis and sialic acid storage disorders led to the identification of two lysosomal transporters for cystine and sialic acids, respectively, ten years ago, most transporters responsible for exporting lysosomal hydrolysis products ...
Mühlhausen C - - 2008
The neurodegenerative disorder glutaric aciduria type I (GA I) is characterized by increased levels of cytotoxic metabolites such as glutaric acid (GA) and 3-hydroxyglutaric (3OHGA). The present report summarizes recent investigations providing insights into mechanisms of intra- and intercellular translocation of these metabolites. Initiated by microarray analyses in a mouse ...
Bröer Stefan - - 2008
Absorption of amino acids in kidney and intestine involves a variety of transporters for different groups of amino acids. This is illustrated by inherited disorders of amino acid absorption, such as Hartnup disorder, cystinuria, iminoglycinuria, dicarboxylic aminoaciduria, and lysinuric protein intolerance, affecting separate groups of amino acids. Recent advances in ...
Baiga Thomas J - - 2008
Caenorhabditis elegans sense natural chemicals in their environment and use them as cues to regulate their development. This investigation probes the mechanism of sensory trafficking by evaluating the processing of fluorescent derivatives of natural products in C. elegans. Fluorescent analogs of daumone, an ascaroside, and apigenin were prepared by total ...
Negi Sangeeta - - 2008
Lateral root branching is a genetically defined and environmentally regulated process. Auxin is required for lateral root formation, and mutants that are altered in auxin synthesis, transport or signaling often have lateral root defects. Crosstalk between auxin and ethylene in root elongation has been demonstrated, but interactions between these hormones ...
Tlalka Monika - - 2008
alpha-Aminoisobutyric acid (AIB) is a nonmetabolized amino acid analogue of alanine, which at low (muM) concentrations acts as a tracer for amino acid movements. At high concentrations (mM), it competitively inhibits membrane transport and metabolism of protein amino acids and acts as a systemic translocated inhibitor of mycelial extension in ...
Friesema Edith C H - - 2008
Cellular entry of thyroid hormone is mediated by plasma membrane transporters, among others a T-type (aromatic) amino acid transporter. Monocarboxylate transporter 10 (MCT10) has been reported to transport aromatic amino acids but not iodothyronines. Within the MCT family, MCT10 is most homologous to MCT8, which is a very important iodothyronine ...
Kashiwagi Hitoshi - - 2009
Several studies have demonstrated that the activity of system A is upregulated by insulin, osmotic shock and amino acid deprivation. However, the mechanisms are not clear. We carried out studies using L6 rat skeletal muscle cells to clarify the mechanisms of upregulation of system A activity by insulin, osmotic shock ...
Shaoping Hu - - 2008
The role of acid rain in affecting Pb and As transport from mine tailings was investigated by pumping simulated acid rain at a infiltration rate of 10.2 cm/h through soil columns. Simulated acid rain with pH of 3.0, 4.5 and 5.6 were used as leaching solutions. Results showed that 86.9-95.9% ...
Zhang Zhou Z Department of Physiology and Biophysics, University of Miami School of Medicine, Miami, Florida 33136, - - 2008
The neutral amino acid transporter 2 (SNAT2), which belongs to the SLC38 family of solute transporters, couples the transport of amino acid to the cotransport of one Na(+) ion into the cell. Several polar amino acids are highly conserved within the SLC38 family. Here, we mutated three of these conserved ...
Islam Rafiqul - - 2008
In this study, we have elucidated that propionate, one of the short chain fatty acids (SCFAs), is the transport substrate for murine organic anion transporter 2 (mOat2), which is expressed in the kidneys and the liver. When expressed in Xenopus oocytes, mOat2-mediated [(3)H]PGE(2) transport was inhibited by three- to five-carbon ...
Uchiyama Tomomi - - 2008
Cationic amino acid transport in primary cultured rat pneumocytes exhibiting characteristics of alveolar epithelial type I-like cells are described. Asymmetry and activator ion dependency of (3)H-L-arginine uptake were characterized from the apical or basolateral fluid of pneumocytes grown on permeable support. Substrate specificity of transport was evaluated as a function ...
Visser W Edward - - 2008
Thyroid hormone (TH) is essential for the proper development of numerous tissues, notably the brain. TH acts mostly intracellularly, which requires transport by TH transporters across the plasma membrane. Although several transporter families have been identified, only monocarboxylate transporter (MCT)8, MCT10 and organic anion-transporting polypeptide (OATP)1C1 demonstrate a high degree ...
Corpeleijn E - - 2008
Enhanced fatty acid uptake may lead to the accumulation of lipid intermediates. This is related to insulin resistance and type 2 diabetes mellitus. Rodent studies suggest that fatty acid transporters are acutely regulated by insulin. We investigated differences in fatty acid transporter content before and at the end of a ...
Banerjee Antara - - 2008
The hASBT (human apical Na(+)-dependent bile acid transporter) constitutes a key target of anti-hypercholesterolaemic therapies and pro-drug approaches; physiologically, hASBT actively reclaims bile acids along the terminal ileum via Na(+) co-transport. Previously, TM (transmembrane segment) 7 was identified as part of the putative substrate permeation pathway using SCAM (substitute cysteine ...
Cleal J K - - 2008
The mechanisms by which amino acids are transferred across the human placenta are fundamental to our understanding of foetal nutrition. Amino acid transfer across the human placenta is dependent on transport across both the microvillous and basal plasma membranes of the placental syncytiotrophoblast, and on metabolism within the syncytiotrophoblast. Although ...
Gilbert Elizabeth R - - 2008
The objective of this study was to evaluate the effect of dietary protein quality on intestinal peptide transporter (PepT1), amino acid transporter [Na+-independent cationic and zwitterionic amino acid transporter (b(o,+)AT), excitatory amino acid transporter 3 (EAAT3), Na+-independent cationic and Na+-dependent neutral amino acid transporter (y+ LAT2), and Na+-independent cationic amino ...
Mitani Namiki - - 2008
Lsi1 (OsNIP2;1) is the first silicon (silicic acid) transporter identified in plant, which belongs to the nodulin 26-like intrinsic membrane protein (NIP) subfamily. In this study, we characterized the function of this transporter by using the Xenopus laevis oocyte expression system. The transport activity of Lsi1 for silicic acid was ...
Leuzzi Vincenzo - - 2008
Creatine transporter 1 (CT1) defect is an X-linked disease that causes severe neurological impairment. No treatment has been available for this condition so far. Because the transport of creatine (Cr) precursors Gly and Arg is not affected in this disorder, we tested the possible corrective effect of these two amino ...
DiRusso Concetta C CC Center for Metabolic Disease, Ordway Research Institute, 150 New Scotland Avenue, Albany, New York 12208, - - 2008
Fatty acid transport proteins (FATP) function in fatty acid trafficking pathways, several of which have been shown to participate in the transport of exogenous fatty acids into the cell. Members of this protein family also function as acyl CoA synthetases with specificity towards very long chain fatty acids or bile ...
Aiken Kimberly J - - 2008
Organisms respond to available nutrient levels by rapidly adjusting metabolic flux, in part through changes in gene expression. A consequence of adaptations in metabolic rate is the production of mitochondria-derived reactive oxygen species. Therefore, we hypothesized that nutrient sensing could regulate the synthesis of the primary defense of the cell ...
Kobayashi Shoko - - 2008
Our recent study [S. Kobayashi, S. Tanabe, M. Sugiyama, Y. Konishi, Transepithelial transport of hesperetin and hesperidin in intestinal Caco-2 cell monolayers, Biochim. Biophys. Acta, 1778 (2008) 33-41] shows that the mechanism of absorption of hesperetin involves both proton-coupled active transport and transcellular passive diffusion. Here, as well as analyzing ...
Minka N S - - 2008
The effects of ascorbic acid (AA) on pullets transported by road for 6h during the hot-dry season were investigated. Forty Shika Brown pullets administered orally with AA just before transportation served as experimental, while another 40 pullets given sterile water only served as control. Blood samples analyzed before and after ...
Grillo M A - - 2008
Amino acids are transported across the human placenta mediated by transporter proteins that differ in structure, mechanism and substrate specificity. Some of them are Na+-dependent systems, whereas others are Na+-independent. Among these there are transporters composed of a heavy chain, a glycoprotein, and a light chain. Moreover, they can be ...
Bröer Stefan - - 2008
The transport of amino acids in kidney and intestine is critical for the supply of amino acids to all tissues and the homeostasis of plasma amino acid levels. This is illustrated by a number of inherited disorders affecting amino acid transport in epithelial cells, such as cystinuria, lysinuric protein intolerance, ...
Huang Qian - - 2008
OBJECTIVE: Serious trauma to the body often is associated with changes in protein metabolism in multiple organs and tissues. Clinically, the catabolic response results in a generalized negative nitrogen balance. Nutrition support has been an important component of the care of seriously traumatized patients. However, during states of severe trauma, ...
Toyooka Terushige - - 2008
BACKGROUND: L-type amino acid transporter 1 (LAT1) is proposed to be a major nutrient transporter at the blood brain barrier. LAT1 requires the heavy chain of 4F2 cell surface antigen (4F2hc) for functional expression. METHODS: We investigated the expression of this heterodimeric transporter after traumatic spinal cord injury in rat ...
Tsume Yasuhiro - - 2008
A series of amino acid monoester prodrugs of floxuridine was synthesized and evaluated for the improvement of oral bioavailability and the feasibility of target drug delivery via oligopeptide transporters. All floxuridine 5'-amino acid monoester prodrugs exhibited PEPT1 affinity, with inhibition coefficients of Gly-Sar uptake (IC50) ranging from 0.7 - 2.3 ...
Zhe Xing-wei - - 2008
BACKGROUND: High peritoneal transport status in end-stage renal disease patients receiving peritoneal dialysis was shown to be associated with increased morbidity and mortality. Although the pathogenesis of increased peritoneal transport is still not clear, previous studies have demonstrated that phospholipids (PLs) are present on the peritoneal mesothelium and when added ...
Glover Chris N - - 2008
The essential amino acid histidine performs critical roles in health and disease. These functions are generally attributed to the amino acid itself, but could also be mediated by a positive effect on trace element bioavailability. Mechanistic information regarding the absorption of histidine across the gastrointestinal tract is essential for understanding ...
Patel A B - - 2008
A 10 year old girl presented with clinical signs and symptoms of the triad of niacin deficiency namely skin eruptions, ataxia, mental changes and diarrhea. Although this deficiency could be nutritional where maize is a staple diet, this patient had neutral aminoaciduria which indicated a defective transport of neutral amino ...
Kulka Richard G - - 2008
Epiphyllous plantlets develop on leaves of Bryophyllum marnierianum when they are excised from the plant. Shortly after leaf excision, plantlet shoots develop from primordia located near the leaf margin. After the shoots have enlarged for several days, roots appear at their base. In this investigation, factors regulating plantlet root development ...
Jarkas Nachwa - - 2008
N, N-dimethyl-2-(2'-amino-4'-hydroxymethylphenylthio)benzylamine (38), substituted on ring A, was reported to display high binding affinity and selectivity to the human brain serotonin transporter (SERT). In an attempt to explore the potential of compounds substituted on ring B of the phenylthiophenyl core structure, three derivatives of 38 were synthesized: N, N-dimethyl-2-(2'-amino-4'-hydroxymethyl-phenylthio)-5-fluorobenzylamine (35), ...
Larsson Emma - - 2008
Current hypotheses concerning the role of polar auxin transport in embryo development are entirely based on studies of angiosperms, while little is known about how auxin regulates pattern formation in gymnosperms. In this study, different developmental stages of somatic embryos of Norway spruce (Picea abies) were treated with the polar ...
1 2 3 4 5 6 7 8 9 10 >