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Singh, Santosh Kumar
Phosphorous (P) starved cells of the cyanobacterium Anabaena oryzae   showed higher phosphate uptake rates than P-sufficient cells. The P-uptake obeyed saturation kinetics. The Km value for P-deficient cells was lower (54.34 μM) than P-sufficient cells (82.64 μM) while Vmax was higher in P-deficient and lower in P-sufficient cells. Salinity ...
Meller Birgit - - 2008
PURPOSE: In radioiodine therapy the "stunning phenomenon" is defined as a reduction of radioiodine uptake after diagnostic application of (131)I. In the current study, we established an in vitro model based on the "Fisher rat thyrocyte cell line no. 5" (FRTL-5) to investigate the stunning. METHODS: TSH-stimulated FRTL-5 cells were ...
Vumma Ravi - - 2008
Human fibroblast cells are an advantageous model to study the transport of amino acids across cell membranes, since one can control the environmental factors. A major problem in all earlier studies is the lack of precise and detailed knowledge regarding the expression and functionality of tyrosine transporters in human fibroblasts. ...
Orbán Tamás I - - 2008
ABCG2 is a half-transporter which causes multidrug resistance when overexpressed in tumor cells. Availability of combined localization and functional assays would greatly improve cell biology and drug modulation studies for this transporter. Here we demonstrate that an N-terminally GFP-tagged version of the protein (GFP-G2) can be used to directly monitor ...
Shiao-Wen Tsai
In this study, we demonstrate that the uptake rate of the surface-modified gold nanoparticles (GNPs) with folic acid by specific cells can be increased significantly, if the membranes of these cells have sufficient folic-acid receptors. Two human breast cancer cell lines were studied; one is MDA-MB-435S cell, and the other ...
Maubach, Julie
Epidemiological studies comparing typical Western and traditional Eastern lifestyles indicate that dietary intake of soyderived phytoestrogens, including genistein, daidzein, and equol, may have significant health protective effects on hormone-dependent cancers, osteoporosis and cardiovascular diseases. Phytoestrogens have been demonstrated to exert varying effects depending on tissue, endogenous hormone concentrations, and receptor ...
Lai Yin Hwa - - 2008
The purpose of this study was to construct a human M cell model to evaluate the transport of polystyrene and albumin microparticles via this model. The integrity of the M cell model was evaluated by determining the transepithelial electrical resistance (TEER), and the alkaline phosphate activity was determined as an ...
Tagawa Maki - - 2008
FITC-albumin uptake by cultured alveolar type II epithelial cells, RLE-6TN, is mediated by high- and low-affinity transport systems. In this study, characteristics of the low-affinity transport system were evaluated. The uptake of FITC-albumin was time and temperature dependent and was inhibited by metabolic inhibitors and bafilomycin A1. Confocal laser scanning ...
Lecona Emilio - - 2008
Butyrate has antitumorigenic effects on colon cancer cells, inhibits cell growth and promotes differentiation and apoptosis. These effects depend on its intracellular concentration, which is regulated by its transport. We have analysed butyrate uptake kinetics in human colon adenocarcinoma cells sensitive to the apoptotic effects of butyrate (BCS-TC2, Caco-2 and ...
Minarowska Alina - - 2008
A literature survey was performed of human cathepsin D gene, cathepsin D biosynthesis, posttranslatory modifications, transport within the cell, substrate specificity and catalytic effect. Methods used to determine the activity and level of this proteinase as well as its role in the biochemistry and pathobiochemistry of cells, tissues and organs ...
Frampton John P - - 2008
Cell culture models can provide information pertaining to the effective dose, toxiciology, and kinetics, for a variety of neuroactive compounds. However, many in vitro models fail to adequately predict how such compounds will perform in a living organism. At the systems level, interactions between organs can dramatically affect the properties ...
Zhang Ke - - 2008
This paper reports the synthesis of shell crosslinked nanoparticles (SCKs) of spherical and cylindrical shapes, and their functionalization with folate using a poly(ethylene glycol) (PEG) construct that has folate and an amine group as the opposing chain termini. By use of confocal microscopy, we demonstrate the selective delivery of folate ...
Weerachayaphorn Jittima J Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-0645, - - 2008
Citric acid cycle intermediates are absorbed from the gastrointestinal tract through carrier-mediated mechanisms, although the transport pathways have not been clearly identified. This study examines the transport of citric acid cycle intermediates in the Caco-2 human colon carcinoma cell line, often used as a model of small intestine. Inulin was ...
Bianchi M G - - 2008
The transport of excitatory amino acids (EAA) in CNS is performed by a family of high affinity, sodium dependent carriers. One of these transporters, excitatory amino acid carrier 1 (EAAC1), is known to be regulated by several mechanisms that modify carrier abundance on the plasma membrane. Much less is known ...
Abib Renata T - - 2008
There is a current interest in dietary compounds, such as green tea polyphenols, that can favor protection against a variety of brain disorders, including Alzheimer's disease, ischemia, and stroke. The objective of the present study was to investigate the effects of (-)-epicatechin-3-gallate (ECG), one of three three major green tea ...
Maubon Nathalie - - 2007
Expression of drug transporters corresponds to a crucial parameter in intestinal Caco-2 cells widely used for investigating drug absorption. In order to characterize it in an accurate, reproducible and comparative manner, we analyzed mRNA levels of 19 influx and efflux drug transporters through real-time quantitative polymerase chain reaction assays combined ...
Gnida Manuel - - 2007
Sulfur is essential for life, with important roles in biological structure and function. However, because of a lack of suitable biophysical techniques, in situ information about sulfur biochemistry is generally difficult to obtain. Here, we present an in situ sulfur X-ray absorption spectroscopy (S-XAS) study of living cell cultures of ...
Nelson Allison R AR Department of Physiology and Biophysics, University of California, Irvine, California 92697, - - 2007
Translocation of membrane-impermeant molecules to the interior of living cells is a necessity for many biochemical investigations. Myristoylation was studied as a means to introduce peptides into living cells. Uptake of a myristoylated, fluorescent peptide was efficient in the B lymphocyte cell line BA/F3. In contrast, this cell line was ...
Abdallah Abdallah M - - 2007
Recent evidence shows that mycobacteria have developed novel and specialized secretion systems for the transport of extracellular proteins across their hydrophobic, and highly impermeable, cell wall. Strikingly, mycobacterial genomes encode up to five of these transport systems. Two of these systems, ESX-1 and ESX-5, are involved in virulence - they ...
Rouse Jillian G - - 2008
The effects of quantum dots (QD) on cell viability have gained increasing interest due to many recent developments utilizing QD for pharmaceutical and biomedical applications. The potential use of QD nanoparticles as diagnostic, imaging, and drug delivery agents has raised questions about their potential for cytotoxicity. The objective of this ...
Woost Philip G - - 2007
Angiotensin II is a major regulatory peptide for proximal tubule Na(+) reabsorption acting through two distinct receptor subtypes: AT(1) and AT(2). Physiological or pathological roles of AT(2) have been difficult to unravel because angiotensin II can affect Na(+) transport either directly via AT(2) on luminal or peritubular plasma membranes of ...
Muñoz-Martínez Francisco - - 2008
Perifosine is a promising anticancer alkylphospholipid (ALP) that induces apoptosis in tumor cells. Here we report evidences against a role of endocytosis in perifosine uptake by human KB carcinoma cells. We have generated a KB cell line resistant to perifosine (KB PER(R) clone10), which shows cross-resistance to the ALPs miltefosine ...
Hillmann Petra - - 2008
High blood levels of ammonium/ammonia (NH(4)(+)/NH(3)) are associated with severe neurotoxicity as observed in hepatic encephalopathy (HE). Astrocytes are the main targets of ammonium toxicity, while neuronal cells are less vulnerable. In the present study, an astrocytoma cell line 1321N1 and a neuroblastoma glioma hybrid cell line NG108-15 were used ...
Sun Chuanxin - - 2007
Antisense oligodeoxynucleotides (ODNs) are short (12-25 nt long) stretches of single-stranded DNA that may be delivered to a cell, where they hybridize to the cognate mRNA in a sequence-specific manner, thereby inhibiting gene expression. Here we used confocal microscopy to monitor the uptake and trafficking of ODNs in barley tissues. ...
Zaidi Nousheen - - 2007
Selective inhibition of enzymes involved in antigen processing such as cathepsin E and cathepsin D is a valuable tool for investigating the roles of these enzymes in the processing pathway. However, the aspartic protease inhibitors, including the highly potent pepstatin A (PepA), are inefficiently transported across the cell membrane and ...
Kaper Thijs - - 2007
Mammalian cells rely on cellular uptake of the essential amino acid tryptophan. Tryptophan sequestration by up-regulation of the key enzyme for tryptophan degradation, indoleamine 2,3-dioxygenase (IDO), e.g., in cancer and inflammation, is thought to suppress the immune response via T cell starvation. Additionally, the excreted tryptophan catabolites (kynurenines) induce apoptosis ...
Kehr Julia - - 2008
Cell-to-cell communication is essential for plant development and adaptation to environmental changes. As a strategy for efficient intercellular communication, plants have evolved a plant-specific symplasmic network connected via plasmodesmata that allows a locally restricted information exchange from cell to cell. A rapid information transfer over long distances is enabled via ...
Wenika Benjapong
Thesis (M.Sc.)--Chulalongkorn University, 2000
Wykoff Dennis D DD Howard Hughes Medical Institute, FAS Center for Systems Biology, Harvard University, 7 Divinity Avenue, Bauer 307, Cambridge, MA 02138, - - 2007
The regulation of transporters by nutrient-responsive signaling pathways allows cells to tailor nutrient uptake to environmental conditions. We investigated the role of feedback generated by transporter regulation in the budding yeast phosphate-responsive signal transduction (PHO) pathway. Cells starved for phosphate activate feedback loops that regulate high- and low-affinity phosphate transport. ...
Jähnichen Sabine - - 2007
Batch culture experiments with the cyanobacterium Microcystis aeruginosa PCC 7806 were performed in order to test the hypothesis that microcystins (MCYSTs) are produced in response to a relative deficiency of intracellular inorganic carbon (C(i,i)). In the first experiment, MCYST production was studied under increased C(i,i) deficiency conditions, achieved by restricting ...
Symons Gregory M - - 2008
Brassinosteroids (BRs) are steroidal plant hormones that are important regulators of plant growth. These compounds are widely distributed throughout reproductive and vegetative plant tissues. This raises the question of whether or not BRs are transported over long distances between these tissues. Several lines of evidence indicate that this is not ...
Thors L L Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, - - 2007
Genistein, a tyrosine kinase inhibitor used to block caveolae dependent endocytosis, reduces the cellular uptake of anandamide in RBL2H3 basophilic leukaemia cells. However, genistein is also a competitive inhibitor of fatty acid amide hydrolase, the enzyme responsible for anandamide hydrolysis. Here we have investigated whether inhibition of fatty acid amide ...
Vink Stefan R - - 2007
Perifosine is a member of the class of synthetic alkylphospholipids (APLs) and is being evaluated as anti-cancer agent in several clinical trials. These single-chain APLs accumulate in cellular membranes and disturb lipid-dependent signal transduction, ultimately causing apoptosis in a variety of tumor cells. The APL prototype edelfosine was previously found ...
Pipkorn R - - 2007
This paper presents the BioShuttle platform as a delivery vehicle for transfer of contrast agents and genetic material into target cells, which can be followed by activation of the BioShuttle inside the target cell. Here, we present a transporter system and summarize the findings on transporter use in vivo and ...
Shi Lewis Zhichang LZ School of Health Sciences, Purdue University, 550 Stadium Mall Drive, Room 1163D, West Lafayette, IN 47907-2051, United - - 2008
Immortalized rat choroidal epithelial Z310 cells have the potential to become an in vitro model for studying transport of materials at blood-cerebrospinal fluid barrier (BCB) (Shi and Zheng, 2005) [Shi, L.Z., Zheng, W., 2005. Establishment of an in vitro brain barrier epithelial transport system for pharmacological and toxicological study. Brain ...
Barac-Nieto Mario - - 2007
In opossum kidney (OK) cells as well as in kidney proximal tubules, P(i) depletion increases apical (A) and basolateral (B) Na(+)-dependent P(i) cell influxes. In OK cells' monolayers in contrast to proximal tubules, there is no increase in transepithelial P(i) transport. This limitation may be due to altered cell-matrix interactions. ...
Juchaux-Cachau Marjorie - - 2007
A second mannitol transporter, AgMaT2, was identified in celery (Apium graveolens L. var. dulce), a species that synthesizes and transports mannitol. This transporter was successfully expressed in two different heterologous expression systems: baker's yeast (Saccharomyces cerevisiae) cells and tobacco (Nicotiana tabacum) plants (a non-mannitol-producing species). Data indicated that AgMaT2 works ...
Subramanian Veedamali S - - 2007
The micronutrient thiamine is required for normal growth and development of human tissues, and is accumulated into cells through the activity of plasma membrane thiamine transporters, e.g. hTHTR1 (human thiamine transporter 1). Recent genetic evidence has linked mutations in hTHTR1 with the manifestation of TRMA (thiamine-responsive megaloblastic anaemia), a condition ...
Maeda Tomoji - - 2007
Throughout the mammalian spermatogenic pathway, differentiating spermatogenic cells remain in close contact with somatic Sertoli cells, and this has been considered to be essential for the proliferation, differentiation, and survival of spermatogenic cells. It is thought that Sertoli cells form tight junctions to protect developing spermatogenic cells against harmful agents ...
Bone Derek B J - - 2007
Nucleosides are accumulated by cells via a family of equilibrative transport proteins (ENTs). An alternative splice variant of the most common subtype of mouse ENT (ENT1) has been identified which is missing a protein kinase CK2 (casein kinase 2) consensus site (Ser(254)) in the central intracellular loop of the protein. ...
Pang Yan - - 2007
Used in the brewing of beer, hops (Humulus lupulus L.) contain the prenylated chalcone xanthohumol, which is under investigation as a cancer chemoprevention agent and as a precursor for the estrogenic flavanones isoxanthohumol and 8-prenylnaringenin. The uptake, transport and accumulation of xanthohumol were studied using the human intestinal epithelial cell ...
Zhou Fanfan F Department of Pharmaceutics, Rutgers, The State University of New Jersey, 160 Frelinghuysen Road, Piscataway, New Jersey 08854, - - 2008
To compare the interaction of human organic anion transporter hOAT4 with PDZ proteins between kidney cells and placental cells. PDZ proteins PDZK1 and NHERF1 were transfected into kidney LLC-PK1 cells and placental BeWo cells expressing hOAT4 or hOAT4-Delta, which lacks the PDZ consensus binding site. The interaction of PDZK1 and ...
Meng Zhen - - 2007
The aim of this study was to investigate whether ginsenoside Rg1 could be transported into rat pulmonary epithelial cells and its transport behavior and efflux through the cells. A high-performance liquid chromatography coupled with 2487 UV-vis detector at 203 nm was applied. The mobile phase was 0.05% phosphate-acetonitrile (75:25, v/v). ...
Choi Kyung Min - - 2007
A spectrophotometric assay to determine peptide transport has been developed. Using two chromogenic peptide mimetics, L-phenylalanyl-L-2-sulfanilylglycine (PSG) and L-phenylalanyl-L-3-thiaphenylalanine (PSP), the peptide transport patterns in individual cell species can be evaluated effectively. After the addition of PSG to a HeLa cell suspension, sulfanilic acid accumulated progressively inside, but not outside, ...
Simm Claudia - - 2007
Previous studies of the yeast Saccharomyces cerevisiae indicated that the vacuole is a major site of zinc storage in the cell. However, these studies did not address the absolute level of zinc that was stored in the vacuole nor did they examine the abundances of stored zinc in other compartments ...
Hansen James E - - 2007
Regulation of gene expression by intranuclear transduction of macromolecules such as transcription factors is an alternative to gene therapy for the treatment of numerous diseases. The identification of an effective intranuclear delivery vehicle and pathway for the transport of therapeutic macromolecules across plasma and nuclear membranes, however, has posed a ...
Nüsing Rolf M - - 2007
We investigated the effects of epoxyeicosatrienoic acids (EETs) on ion transport in the polarized renal distal tubular cell line, Madin-Darby canine kidney (MDCK) C7. Of the four EET regioisomers (5,6-EET, 8,9-EET, 11,12-EET, and 14,15-EET) studied, only apical, but not basolateral, application of 5,6-EET increased short-circuit current (I(sc)) with kinetics similar ...
Pinho Maria João - - 2007
This study examined the inward transport of l-[(14)C]alanine, an ASCT2 preferential substrate, in monolayers of immortalized renal proximal tubular epithelial (PTE) cells from Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats. The expression of ASCT2 in WKY and SHR PTE cells and kidney cortices from WKY and SHR was also evaluated. ...
Isome Masato - - 2007
Polyamines are small cationic molecules required for cellular proliferation. Agmatine is a biogenic amine unique in its capacity to arrest proliferation in cell lines by depleting intracellular polyamine levels. We previously demonstrated that agmatine enters mammalian cells via the polyamine transport system. As polyamine transport is positively correlated with the ...
Awasthi Yogesh C - - 2007
RLIP76 or Ral binding protein (RalBP-1) was initially cloned as a Ral-effector that was proposed as a link between Ral and Ras pathways. This protein is encoded in humans on chromosome 18p11.3 by a gene with 11 exons and 9 introns and is found ubiquitously from drosophila to humans. RLIP76 ...
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