A hallmark of congestive heart failure (CHF) is the activation of the cardiac endocrine system, in particular atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). The natriuretic peptides are a group of structurally similar but genetically distinct peptides that have diverse actions in cardiovascular, renal, and endocrine homeostasis. ANP and BNP are of myocardial cell origin and C-type natriuretic peptide (CNP) is of endothelial origin. ANP and BNP bind to the natriuretic peptide-A receptor (NPR-A), which, via 3',5'-cyclic guanosine monophosphate (cGMP), mediates natriuresis, vasodilatation, renin inhibition, antimitogenesis, and lusitropic properties. CNP lacks natriuretic actions but possesses vasodilating and growth inhibiting actions via the guanylyl cyclase-linked natriuretic ...
Recombinant biotin-binding phages were affinity-selected from a random peptide library expressed on the surface of filamentous phage. Phage binding to biotinylated proteins was half-maximally inhibited...Full Text Available
Four major natriuretic peptides have been isolated: atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), C-type natriuretic peptide (CNP), and Dendroaspis-type natriuretic peptide (DNP). Natriuretic peptides play an important role in the regulation of cardiovascular homeostasis maintaining blood pressure and extracellular fluid volume. The classical endocrine effects of natriuretic peptides to modulate fluid and electrolyte balance and vascular smooth muscle tone are complemented by autocrine and paracrine actions that include regulation of coronary blood flow and, therefore, myocardial perfusion; modulation of proliferative responses during myocardial and vascular remodeling; and cytoprotective anti-ischemic effects. The actions of natriuretic peptides are mediated by the specific binding of these ...
Peptide toxins with high affinity, divergent pharmacological functions, and isoform-specific selectivity are powerful tools for investigating the structure-function relationships of voltage-gated...Full Text Available
Constitutive activation of the transcription factor Stat5 in hematopoietic stem/progenitor cells leads to various hematopoietic malignancies including myeloproliferative neoplasm (MPN). Our recent study...Full Text Available
Antibodies to hemoglobin have been studied with a radioimmunoassay which employs ["1"4C]carbamylated (= carbamoylated) hemoglobin S. An antiserum raised against hemoglobin S, which initially discriminated poorly between hemoglobins S and A, was fractionated by absorption to a column of Sepharose to which a synthetic peptide corresponding to the first 13 amino-acid residues of the #beta# chain of sickle hemoglobin had been covalently bound. A subpopulation of the antiserum was eluted from this column with 4 M guanidine . HCl. These antibodies showed binding to hemoglobin S but not to hemoglobin A and this interaction could be inhibited by the synthetic peptide. These antibodies, of demonstrated fine structural specificity, may be useful in the detection of sickle hemoglobin and in the study of its structure in solution.
This study was conducted to investigate the antibacterial effect of BSAP-254 on Bacillus cereus with the induced stress proteins. The BSAP-254 is an antimicrobial peptide isolated from soybean-fermenting bacteria, Bacillus subtilis SC-8. It had a narrow spectrum of activity against B. cereus group. The growth inhibitory effect of BSAP-254 (50??g/mL) reduced the population of B. cereus from >108 to 104 colony-forming units per milliliter within 30?min. In B. cereus exposed to BSAP-254, 14 intracellular proteins were differentially expressed as determined by 2-DE coupled with MS. Of the differentially expressed proteins identified, the stress protein GroEL, which is heat shock protein, was induced in B. cereus exposed to antibacterial peptide.
Human heat shock protein 27 (Hsp27, HspB1) is an anti-apoptotic protein characterized for its tumorigenic and metastatic properties, and now referenced as a major therapeutic target in many types of cancer. Hsp27 biochemical properties rely on a structural oligomeric and dynamic organization. Downregulation by small interfering RNA or inhibition with dominant-negative mutant have proven their efficiency to counteract the anti-apoptotic and protective properties of Hsp27. In this study, we report the isolation and characterization of Hsp27-targeted molecules interfering with its structural organization. Using the peptide aptamer (PA) strategy, we isolated PAs that specifically interact with Hsp27 and not with the other members of the small heat shock protein family. In mammalian cell cultur...
There are about fifty SET domain protein methyltransferases (PMTs) in the human genome, that transfer a methyl group from S-adenosyl-L-methionine (SAM) to substrate lysines on histone tails or other peptides. A number of structures in complex with cofactor, substrate, or inhibitors revealed the mechanisms of substrate recognition, methylation state specificity, and chemical inhibition. Based on these structures, we review the structural chemistry of SET domain PMTs, and propose general concepts towards the development of selective inhibitors.
CAP18 (an 18-kDa cationic antimicrobial protein) is a granulocyte-derived protein that can bind lipopolysaccharide (LPS) and inhibit various activities of LPS in vitro. The present study examined the...Full Text Available
The catecholamine release-inhibitory catestatin [Cts; human chromogranin (Cg) A352-372, bovine CgA344-364] is a vasoreactive and anti-hypertensive peptide derived...Full Text Available
BackgroundDespite an ever-improving understanding of the molecular biology of cancer, the treatment of most cancers has not changed dramatically in the past three decades and drugs that do not discriminate between tumor cells and normal tissues remain the mainstays of anticancer therapy. Since Hsp90 is typically involved in cell proliferation and survival, this is thought to play a key role in cancer, and Hsp90 has attracted considerable interest in recent years as a potential therapeutic target.MethodsWe focused on the interaction of Hsp90 with its cofactor protein p60/Hop, and engineered a cell-permeable peptidomimetic, termed "hybrid Antp-TPR peptide", modeled on the binding interface between the molecular chaperone Hsp90 and the TPR2A domain of Hop.ResultsIt was demonstrated that this designed hybrid Antp-TPR peptideinhibited the interaction of Hsp90 with the TPR2A domain, inducing cell death of breast, pancreatic, ...
Cancer cells recruit monocytes, macrophages and other inflammatory cells by producing abundant chemoattractants and growth factors, such as macrophage colony-stimulating factor (M-CSF/CSF-1) and monocyte chemoattractant protein-1 (MCP-1/CCL2), to promote tumor growth and dissemination. An understanding of the mechanisms that target cancer cells and regulate tumor microenvironment is essential in designing anticancer therapies. Here, we showed that serum amyloid-A (SAA) and cathelicidin (LL-37) stimulated M-CSF and MCP-1 expression with or without lipopolysaccharide (LPS) administration; conversely, lipoxin-A4 (LXA4) and annexin-A1 (ANXA1) inhibited LPS-induced M-CSF and MCP-1 production by human (HepG2) and mouse (H22) hepatocellular carcinoma cells (HCCs). The effects of LXA4, ANXA1, SAA ...
The present study investigated the effects of peppermint (Mentha piperita), dill (Anethum graveolens) and basil (Ocimum basilicum) on yogurt formation, proteolysis and inhibition of angiotensin-1 converting enzyme (ACE). Herbal-yogurts had faster rates of pH reduction than plain-yogurt. All herbal-yogurts had higher (p < 0.05) antioxidant activities than plain-yogurt, both at the end of fermentation and throughout the storage period. The o-phthalaldehyde (OPA) peptides in herbal-yogurts increased by 28-36% after 7 days of storage. All herbal-yogurts showed higher anti-ACE activity than plain-yogurt at corresponding storage periods. M. piperita yogurt had highest inhibitory effect on ACE activity throughout the storage period. Peppermint, dill and basil may be used to modify microbial ferme...
2-Azido[#alpha#-"3"2P]adenosine diphosphate (2-azido[#alpha#-"3"2P]ADP) has been used to photolabel the ADP/ATP carrier in beef heart mitochondria. In reversible binding assays carried out in the dark, this photoprobe was found to inhibit ADP/ATP transport in beef heart mitochondria and to bind to two types of specific sites of the ADP/ATP carrier characterized by high-affinity binding (K/sub d/ = 20 #mu#M) and low-affinity binding (K/sub d/ = 400 #mu#M). In contrast, it was unable to bind to specific carrier sites in inverted submitochondrial particles. Upon photoirradiation of beef heart mitochondria in the presence of 2-azido[#alpha#-"3"2P]ADP, the ADP/ATP carrier was covalently labeled. After purification, the photolabeled carrier protein was cleaved chemically by acidolysis or cyanogen bromide and enzymatically with the Staphylococcus aureus V8 protease. In the ADP/ATP carrier protein, which is 297 amino acid residues in length, two discrete regions extending ...
Aminophenpyramine, a derivative of mepyramine (pyrilamine), a typical antagonists of histamine at its H_1 receptor was synthesized and converted into ["1"2"5I]iodoazidophenpyramine, a potential photoaffinity probe for the H_1 receptor. In the dark, reversible binding of this probe to cerebellar membranes occurred with a K/sub d/ of 1.2 x 10"-"1"1 M and a B/sub max/ of 240 fmol/mg of protein and was inhibited by various H_1-receptor antagonists with the expected potencies. These features establish the compound as one of the most potent H_1-receptor antagonists known so far. Upon IV irradiation, 5% of the bound radioactivity was covalently incorporated into cerebellar membrane polypeptides as shown by standard NaDodSO_4/PAGE. Two bands of 47 and 56 kDa were consistently labeled, labeling being prevented by various H_1-receptor antagonists with the expected potencies and stereoselectivity. In the presence of protease inhibitors, labeling of the 56-kDa ...
The authors have shown previously that the domain recognizing receptors on activated human platelets is located on the human fibrinogen {gamma} chain between residues 400 and 411. To study the correlation between the structure of this segment of the {gamma} chain and its reactivity toward receptors on ADP-activated human platelets, they designed a series of analogues containing replacements at 9 out of 12 positions. A double substitution of the normal His{sup 400}-His{sup 401} sequence by Ala-Ala reduced the inhibitory potency of the dodecapeptide 3-fold. When Lys{sup 406} was replaced by Arg, the inhibitory potency of the dodecapeptide decreased 15 times. On the other hand, substitution of Ala{sup 408} with Arg increased the inhibitory potency of the dodecapeptide 6-fold. A drastic decrease in the reactivity of the dodecapeptide toward platelet receptors was observed when Val{sup 411} was replaced by leucine or cysteine or tyrosine. A 3-fold decrease in reactivity was noted when ...
A general method is described to sequester peptides containing azides from complex peptide mixtures, aimed at facilitating mass spectrometric analysis to study different aspects of proteome...Full Text Available
A pore-forming peptide is implicated in the potent cytolytic activity of pathogenic Entamoeba histolytica. Using NH2-terminal sequence information of this peptide, the corresponding cDNA was isolated....Full Text Available
BackgroundThe binding of peptide fragments of antigens to class II MHC is a crucial step in initiating a helper T cell immune response. The identification of such peptide epitopes...Full Text Available
AIM: To investigate atrial natriuretic peptide (ANP) secretion from gastric mucosa and the relationship between the ANP/natriuretic peptide receptor type A (NPR-A) pathway and diabetic gastroparesis.METHODS:...Full Text Available
The sequences of the peptide binding domains of 33 70 kd heat shock proteins (hsp70) have been aligned and a consensus secondary structure has been deduced. Individual members showed no significant...Full Text Available
BackgroundAmino-terminal signal peptides (SPs) are short regions that guide the targeting of secretory proteins to the correct subcellular compartments in the cell. They are cleaved...Full Text Available
The family of natriuretic peptides consists of the atria natriuretic peptide (ANP), the cerebral natriuretic peptide (BNP), the type C natriuretic peptide (CNP) and the peptide isolated from the dendroaspis snakes' poison (DNP), whose presence in humans has not been confirmed. The physiological function of ANP is in the control of arterial blood pressure by regulation of systemic vascular resistance of blood vessels. BNP is produced as one of the factors in the acute response to inflammatory tissue damage, mainly in coronary vessels. Increased serum concentrations of natriuretic peptides have been found in stress situations, such as trauma or major surgery, systemic hypotension, and in intrinsic myocardial dysfunction. High concentrations of natriuretic peptides were observed in severe sepsis, septic shock and in multiple organ failure, ...
The response of Desulfovibrio vulgaris Hildenborough (DvH),a sulphate-reducing bacterium, to nitrate stress was examined usingquantitative proteomic analysis. DvH was stressed with 105 m M sodiumnitrate(NaNO3), a level that caused a 50 percent inhibition in growth.The protein profile of stressed cells was compared with that of cellsgrown in the absence of nitrate using the iTRAQ peptide labellingstrategy and tandem liquid chromatography separation coupled with massspectrometry (quadrupoletime-of-flight) detection. A total of 737 uniqueproteins were identified by two or more peptides, representing 22 percentof the total DvH proteome and spanning every functional category. Theresults indicate that this was a mild stress, as proteins involved incentral metabolism and the sulphate reduction pathway were unperturbed.Proteins involved in the nitrate reduction pathway increased. Increasesseen in transport systems for proline, ...
Transcriptional regulation of the galactose-metabolizing genes in Saccharomyces cerevisiae depends on three core proteins: Gal4p, the transcriptional activator that binds to upstream activating DNA sequences (UASGAL); Gal80p, a repressor that binds to the carboxyl terminus of Gal4p and inhibits transcription; and Gal3p, a cytoplasmic transducer that, upon binding galactose and adenosine 5'-triphosphate, relieves Gal80p repression. The current model of induction relies on Gal3p sequestering Gal80p in the cytoplasm. However, the rapid induction of this system implies that there is a missing factor. Our structure of Gal80p in complex with a peptide from the carboxyl-terminal activation domain of Gal4p reveals the existence of a dinucleotide that mediates the interaction between the two. Biochemical and in vivo experiments suggests that nicotinamide adenine dinucleotide phosphate (NADP) plays a key role in the initial induction event.
C-type natriuretic peptide (CNP) is a member of the small family of natriuretic peptides that also includes atrial natriuretic peptide (ANP) and brain, or B-type natriuretic peptide (BNP). Unlike them, it performs its major functions in an autocrine or paracrine manner. Those functions, mediated through binding to the membrane guanylyl cyclase natriuretic peptide receptor B (NPR-B), or by signaling through the non-enzyme natriuretic peptide receptor C (NPR-C), include the regulation of endochondral ossification, reproduction, nervous system development, and the maintenance of cardiovascular health. To date, the regulation of CNP gene expression has not received the attention that has been paid to regulation of the ANP and BNP genes. CNP expression in vitro is regulated by TGF-b and recepto...
One of the refinements of modern Nuclear Medicine is the capacity of providing dynamic and kinetics images of the administered radiopharmaceutical, reproducing its transport mechanism, action sites, receptor binding and excretion route. With the continues technological advances new radiopharmaceuticals have been developed in order to express higher specificity and with higher characters of affinity between receptor/complex. One radiopharmaceutical is formed by a reagent or bio molecule that has in its structure a radioisotope, that has the objectives of carrying it to the organs of affinity or to benign or malign tumoral process. Somatostatin inhibits the growing and proliferation of several tumoral cells. Somatostatin analogs bind to somatostatic receptors that are expressed in different kind of neoplasia DOTA-LANREOTIDE (DOTALAN) is an octapeptide analog to somatostatin. The interest of labeling the bio conjugate with gallium-67 in Nuclear Medicine comes from its ...
Glucagon-like peptide-2 (GLP-2) is a nutrient-regulated intestinotrophic hormone derived from proglucagon in the distal intestine. Enteral nutrients (EN) potentiate the action of GLP-2 to reverse parenteral...Full Text Available
BackgroundCalcitonin gene related peptide (CGRP) is a neuropeptide that is abundant in the sensory neurons which innervate bone. The effects of CGRP on isolated bone cells have been...Full Text Available
OBJECTIVEThis randomized, four-arm, placebo-controlled, dose-ranging phase 2 trial was conducted to determine whether repeated subcutaneous injections of the altered peptide ligand,...Full Text Available
A unique antibacterial peptide derivative found in immune honeybee lymph, apidaecin 1b (AP1), was randomly mutagenized and characterized by a newly established system to analyze in vivo its structure-function...Full Text Available
High-density lipoproteins (HDL) were examined as potential carriers of small peptides in plasma. HDL purified by density gradient centrifugation was delipidated and fractionated by size-exclusion...Full Text Available
Atrial natriuretic peptide (ANP) causes relaxation in the opossum lower esophageal sphincter. The effects of dendroaspis natriuretic peptide (DNP) and other natriuretic peptides in the lower esophageal sphincter were not known. We measured the relaxation of transverse strips from the guinea pig lower esophageal sphincter caused by DNP, ANP, brain natriuretic peptide (BNP), C-type natriuretic peptide (CNP), and a natriuretic peptide receptor-C agonist des[Gln^1^8, Ser^1^9, Gly^2^0, Leu^2^1, Gly^2^2]ANP(4-23) amide (cANF(4-23)) in vitro. In resting strips of the guinea pig lower esophageal sphincter DNP and BNP caused marked relaxations. Furthermore, in both sarafotoxin S6c and carbachol-contracted lower esophageal sphincter strips, DNP caused marked and BNP caused moderate, concentration-de...
BackgroundAtrial fibrillation (AF) is the most common cardiac arrhythmia with a population prevalence of about 1%. Natriuretic peptide level is elevated in patients with AF with...Full Text Available
BackgroundMammalian antimicrobial peptides (AMPs) are effectors of the innate immune response. A multitude of signals coming from pathways of mammalian pathogen/pattern recognition...Full Text Available
CART peptides are endogenous neurotransmitters that are involved in a variety of physiologic functions. Injection of CART 55-102 into the nucleus accumbens produces no effect, but when co-administered...Full Text Available
Background: The causes of elevated B-Type natriuretic peptide (BNP) levels are multifactorial. Renal dysfunction has been shown to affect BNP levels in some studies and...Full Text Available
Polyclonal antibodies were raised in rabbits by immunization with free peptides corresponding to positions 197-222 of the human beta 1-adrenergic receptor (beta 1 peptide) and the corresponding sequence...Full Text Available
In the cellular immune response, recognition by CTL-TCRs of viral antigens presented as peptides by HLA class I molecules, triggers destruction of the virally infected cell (Townsend, A.R.M., J. Rothbard,...Full Text Available
The identification of MHC class II restricted peptide epitopes is an important goal in immunological research. A number of computational tools have been developed for this purpose, but there is a lack...Full Text Available
The gastrin releasing peptide (GRP) receptor is becoming an increasingly attractive target for development of new radiolabeled peptides with diagnostic and therapeutic potential. The attractiveness of the GRP receptor as a target is based upon the functional expression of GRP receptors in several tumors of neuroendocrine origin including prostate, breast, and small cell lung cancer. This concise review outlines some of the efforts currently underway to develop new GRP receptor specific radiopharmaceuticals by employing a variety of radiometal chelation systems.
A new proprietary de novo peptide design technique generated ten 15-residue peptides targeting and containing the leading nontransmembrane hydrophobic autocorrelation wavelengths, “modes”,...Full Text Available
Alzheimer's disease (AD) is a neurodegenerative disorder for which the research of new treatments is highly challenging. Since the fibrillogenesis of amyloid-b peptide 1-42 (Ab1-42) peptide is considered as a major cause of neuronal degeneration, specific interest has been focused on aromatic molecules for targeting this peptide. In this paper, the synthesis of selegiline-functionalized and fluorescent poly(alkyl cyanoacrylate) nanoparticles (NPs) and their evaluation for the targeting of the Ab1-42 peptide are reported. The synthetic strategy relied on the design of amphiphilic copolymers by tandem Knoevenagel-Michael addition of cyanoacetate derivatives, followed by their self-assembly in aqueous solutions to give the corresponding NPs. Different cyanoacetates were used: (i) hexadecyl cy...
Abstract Lyme neuroborreliosis (LNB) is a serious but treatable disease. The diagnosis of LNB poses a challenge to clinicians, and improved tests are needed. The C6-peptide ELISA is frequently used on serum but not on cerebrospinal fluid (CSF). Data on the sensitivity of the C6-peptide ELISA in CSF in patients suffering from LNB have been conflicting. Serum-CSF pairs from 59 LNB patients, 36 Lyme non-neuroborreliosis cases, 69 infectious meningitis/encephalitis controls and 74 neurological controls were tested in a C6-peptide ELISA. With the optimal cut-off of 1.1, the sensitivity of the C6-peptide ELISA for LNB patients in CSF was 95%, and the specificity was 83% in the Lyme non-neuroborreliosis patients, 96% in the infectious controls, and 97% in the neurological controls. These results ...
Cholera toxin catalyzes transfer of radiolabel from ["3"2P]NAD"+ to several peptides in particulate preparations of human foreskin fibroblasts. Resolution of these peptides by two-dimensional gel electrophoresis allowed identification of two peptides of M/sub r/ = 42,000 and 52,000 as peptide subunits of a regulatory component of adenylate cyclase. The radiolabeling of another group of peptides (M/sub r/ = 50,000 to 65,000) suggested that cholera toxin could catalyze ADP-ribosylation of cytoskeletal proteins. This suggestion was confirmed by showing that incubation with cholera toxin and ["3"2P]NAD"+ caused radiolabeling of purified microtubule and intermediate filament proteins.
The natriuretic peptides are considered to be cardioprotective; however, their receptors have not been identified in human myocardium using radiolabeled analogs. Dendroaspis natriuretic peptide (DNP) has been recently identified as a new member of this peptide family and is thought to be less susceptible to enzymatic degradation. Therefore, we have developed the novel radiolabeled analog [125I]-DNP and used this to localize high-affinity (K(D)=0.2 nmol/L), saturable, specific binding sites in adult human heart (n=6) and coronary artery (n=8). In competition binding experiments, atrial natriuretic peptide and brain type natriuretic peptide had greater affinity for [125I]-DNP binding sites than C-type natriuretic peptide and the natriuretic peptide receptor (NPR)-C ligand, cANF. This rank order of potency suggested binding of [125I]-DNP was ...
Synthetic atrial natriuretic peptide (carperitide) and B-type natriuretic peptide (BNP; nesiritide) are used to treat congestive heart failure. However, despite beneficial cardiac unloading properties, reductions in renal perfusion pressures limit their clinical effectiveness. Recently, CD-NP, a chimeric peptide composed of C-type natriuretic peptide (CNP) fused to the C-terminal tail of Dendroaspis natriuretic peptide (DNP), was shown to be more glomerular filtration rate-enhancing than BNP in dogs. However, the molecular basis for the increased responsiveness was not determined. Here, we show that the DNP tail has a striking effect on CNP, converting it from a non-agonist to a partial agonist of natriuretic peptide receptor (NPR)-A while maintaining the ability to activate NPR-B. This effect is specific for human receptors because CD-NP was only a slightly ...
Candoxin (PDB #1JGK), a three-finger neurotoxin from Bungarus candidus venom, inhibits post-synaptic neuromuscular and neuronal alpha7nACh-receptors, and induces delayed cell-death throughout the glial population. When applied to cultured human glial cell lines, candoxin (CDX) induced cell death in a concentration (EC(50) approximately 1muM) and time dependent manner. Results of TUNEL-histochemistry further confirm CDX-induced brain (hippocampus, frontal cortex, and temporal regions) damage when administered intracerebroventricularly (i.c.v) in adult mice. In this study, we explored differential gene expression profiles following exposure of human glial (Hs 683) cell lines to CDX at various time intervals using Affymetrix-GeneChips. By means of MAS and GeneSpring analyses, 105 genes whose expression was significantly (P<0.01) altered by at least 3-fold were selected. Results of the genome analysis reveal that the potential role of CDX at molecular level involves ...
The present study was designed to assess the radioprotective effects of amifostine on ovarian follicles. Three week-old female mice with or without pretreatment of amifostine were irradiated with 6.42 Gy of #gamma# -ray. Ovaries were collected 0 and 6h after irradiation. DNA fragmentation pattern and expression of genes and activity of proteins related with apoptosis were investigated by means of RT-PCR and Western blot. Proliferation of granulosa cells was reduced and incidence rate of follicular atresia was increased in ovarian follicles in #gamma# -ray irradiated mice compared to those in control or amifostine-treated group. DNA fragmentation was increased in time-dependent manner in granulosa cells of all irradiated groups. However, no difference between amifostine pre-treated group and irradiated groups was found and the expression of p53 as tumor suppressor gene and Bax as one of pro-apoptotic Bcl-2 family was increased in irradiated mice ovaries. PARP as DNA damage sensor was ...
ATR-X (alpha-thalassemia/mental retardation, X-linked) syndrome is a human congenital disorder that causes severe intellectual disabilities. Mutations in the ATRX gene, which encodes an ATP-dependent chromatin-remodeler, are responsible for the syndrome. Approximately 50% of the missense mutations in affected persons are clustered in a cysteine-rich domain termed ADD (ATRX-DNMT3-DNMT3L, ADD{sub ATRX}), whose function has remained elusive. Here we identify ADD{sub ATRX} as a previously unknown histone H3-binding module, whose binding is promoted by lysine 9 trimethylation (H3K9me3) but inhibited by lysine 4 trimethylation (H3K4me3). The cocrystal structure of ADD{sub ATRX} bound to H3{sub 1-15}K9me3 peptide reveals an atypical composite H3K9me3-binding pocket, which is distinct from the conventional trimethyllysine-binding aromatic cage. Notably, H3K9me3-pocket mutants and ATR-X syndrome mutants are defective in both H3K9me3 binding and ...
The term "homology" or "homologous" means an amino acid similarity measured by the program, BLAST (Altschul et al (1997), "Gapped BLAST and PSI-BLAST: a new generation of protein database search programs", Nucleic Acids Res. 25:33 89 3402), and expressed as --(% identity n/n). In measuring homology between a peptide and a protein of greater size, homology is measured only in the corresponding region; that is, the protein is regarded as only having the same general length as the peptide, allowing for gaps and insertions.
Analytical techniques for analyzing the effects of ship motion and attitude on the primary coolant system flow rates are presented. Design data for minimizing these effects are given. (C.J.G.)
SummaryMammalian iron homeostasis is regulated by the interaction of the liver-produced peptide hepcidin and its receptor, the iron transporter ferroportin. Hepcidin binds to...Full Text Available
In an effort to develop octahedral metal complexes as chemotherapeutic and diagnostic agents targeted to DNA, it is critical to optimize the properties of their cellular uptake. Appending d-octaarginine...Full Text Available
Endogenous opioid peptides are substances involved in cell communication. They are present in various organs and tissues of the male and female reproductive tract, suggesting that they may regulate...Full Text Available
BackgroundGenetic predisposition to scrapie in sheep is associated with several variations in the peptide sequence of the prion protein gene (PRNP). DNA-based tests...Full Text Available
Technology is being developed for preparing functional materials by synthesizing new functional peptides in which non-natural amino acid needed for the functional manifestation is introduced, and by modifying the surface of a base plate such as silica glass by using such peptides. Activities were conducted in the three areas of (1) creation of functional molecules, (2) materialization technology, and (3) comprehensive investigation and research; the activities were carried out independently and parallelly in the first two areas. In (1), design technique for the structures and functions of peptides was developed, as were conformational control technique, synthesis of peptides having optical/electronic functions, peptide synthesis by an enzyme method, and R and D on introduction of non-natural amino acid into peptides; in (2), element technologies were developed ...
This study aims to investigate the difference in the interaction of antimicrobial peptides with two classes of zwitterionic peptides, phosphatidylethanolamines (PE) and phosphatidylcholines (PC). Further experiments were performed on model membranes prepared from specific bacterial lipids, lipopolysaccharides (LPS) isolated from Salmonella minnesota. The structure of the lipid-peptide aqueous dispersions was studied by small-and wide-angle X-ray diffraction during heating and cooling from 5 to 85 C. The lipids and peptides were mixed at lipid-to-peptide ratios 10-10000 (POPE and POPC) or 2-50 (LPS). All experiments were performed at synchrotron soft condensed matter beamline A2 in Hasylab at Desy in Hamburg, Germany. The phases were identified and the lattice parameters were calculated. Alamethicin and melittin interact in similar ways with the lipids. Pure POPC forms only lamellar ...
The effects of D-amino acids at Asp"2"3 and Ser"2"6 residues on the conformational preference of #beta#-amyloid (A#beta#) peptide fragment (A#beta#_2_0_-_2_9) have been studied using different spectroscopic techniques, namely vibrational circular dichroism (VCD), vibrational absorption, and electronic circular dichroism. To study the structure of the A#beta#_2_0_-_2_9, [D-Asp"2"3]A#beta#_2_0_-_2_9, and [D-Ser"2"6]A#beta#_2_0_-_2_9 peptides under different conditions, the spectra were measured in 10 mM acetate buffer (pH 3) and in 2,2,2-trifluoroethanol (TFE). The spectroscopic results indicated that at pH 3, A#beta#_2_0_-_2_9 peptide takes random coil with #beta#-turn structure, while [D-Ser"2"6]A#beta#_2_0_-_2_9 peptide adopts significant amount of polyproline II (PPII) type structure along with #beta#-turn contribution and D-Asp-substituted peptide ([D-Asp"2"3]A#beta#_2_0_-_2_9) ...
Insulin-degrading enzyme (IDE) degrades insulin and other peptides, including the Aβ peptide of Alzheimer’s disease. However, the mechanism by which IDE acts on its substrates...Full Text Available
Staphylococcus aureus survives inside eukaryotic cells. Our objective was to assess the activity of NZ2114, a novel peptidic antibiotic, against intracellular S. aureus in comparison with established antistaphylococcal agents acting on the bacterial envelope with a distinct mechanism.
A collection of neurons in the upper lumbar spinal cord of male rats projects to the lower lumbar spinal cord, releasing gastrin-releasing peptide (GRP) onto somatic and autonomic centers known to regulate...Full Text Available
CD-NP is a novel chimeric natriuretic peptide (NP) consisting of the 22-amino-acid (AA) human C-type natriuretic peptide (CNP), a venodilating peptide with limited renal actions and minimal effects on blood pressure, and the 15-AA C-terminus of Dendroaspis NP (DNP). The rationale for the design of CD-NP was to enhance the renal actions of CNP, the ligand for natriuretic peptide receptor-B, but without inducing excessive hypotension. Here we report the first-in-human studies for CD-NP, which represent the first successful clinical testing of a chimeric NP demonstrating in normal human volunteers that CD-NP possesses cyclic guanosine monophosphate-activating, natriuretic, and aldosterone-suppressing properties without inducing excessive hypotension, laying the foundation for additional studies on this first-in-class new cardiovascular therapeutic in human heart failure, which are now underway worldwide. ...
Cell-penetrating peptides (CPPs) are useful tools for the delivery of hydrophilic bioactive molecules, such as peptides, proteins, and oligonucleotides, across the cell membrane. To realize the delivery of therapeutic macromolecules by CPPs, the CPPs are required to show resistance to protease and no cytotoxicity. In order to produce potent non-toxic and protease-resistant CPPs with high cellular uptake, we designed an amphipathic helix peptide using ?-aminoisobutyric acid (Aib, U) and named it MAP(Aib). In the MAP(Aib) molecule, five Aib residues are aligned on the hydrophobic face of the helix and five lysine (K) residues are aligned on the hydrophilic face. MAP(Aib) showed potent resistance to trypsin and pronase compared with MAP, an amphipathic helix peptide formed by usual amino acids. Fluorescein-labeled MAP(Aib) efficiently traversed the A549 cell membrane, diffusing into the cytoplasm and ...
The acute acetoclastic methanogenic inhibition of several inorganic and organic arsenicals was assayed. Trivalent species, i.e., methylarsonous acid and arsenite, were highly inhibitory, with 50% inhibitory...Full Text Available
6-Mercaptopurine (6-MP) inhibits the growth of. Escherichia coli B. Growth inhibition is ... reversed by subculture of the cells in 6-mercaptopurine- ...
In APCs, presentation by MHC II molecules of the chemically dominant peptide from the protein hen egg white lysozyme (HEL) generates different conformational isomers of the peptide-MHC II complexes (pMHC). Type B pMHCs are formed in early endosomes from exogenous peptides in the absence of H2-DM, whereas in contrast, type A pMHC complexes are formed from HEL protein in late vesicles after editing by H2-DM. Thus, H2-DM edits off the more unstable pMHC complexes, which are not presented from HEL. In this study, we show that type B pMHC complexes were presented from HEL protein only after stimulation of dendritic cells (DC) with TLR ligands or type I IFN. Type I IFN contributed to most TLR ligand-induced type B pMHC generation, as presentation decreased in DC lacking the receptor for type I IFNs (IFNAR1(-/-)). In contrast, presentation of type A pMHC from HEL and from peptide was minimally affected by TLR ...
The amino acid residues 114-118 in actin were found to be implicated strongly in the binding of nucleotide, and as would be expected for such an important binding site, they are located in a completely conserved region of the actin sequence. A 19-residue peptide with the actin sequence 106-124 was synthesized in order to span the putative triphosphate binding site. Proton NMR spectra of the actin peptide 114-118 in the presence and absence of ATP indicated that Arg-116 and Lys-118 are particularly involved in binding ATP. A strong binding of ATP to the peptide 106-124 also was measured. Tripolyphosphate bound to the peptide 106-124 somewhat more weakly than ATP. Binding involved residues 115-118 and 121-124, indicating the presence of a reverse turn between these segments. Proton resonances were assigned by using two-dimensional double quantum correlated spectroscopy, one-dimensional spin decoupling ...
In a given species, injected opioid peptides usually cause changes in temperature similar to those caused by nonpeptide opioids. The main effect in those species most studied, the cat, rat, and mouse, is an increase in the level about which body temperature is regulated; there is a coordinated change in the activity of thermoregulatory effectors such that hyperthermia is produced in both hot and cold environments. Larger doses may depress thermoregulation, thereby causing body temperature to decrease in the cold. Elicitation of different patterns of response over a range of environmental temperatures and studies with naloxone and naltrexone indicate that stimulation of a number of different receptors by both peptide and nonpeptide opioids can evoke thermoregulatory responses. ..beta..-Endorphin is readily antagonized by naloxone whereas methionine-enkephalin can act on naloxone-insensitive receptors. Moreover, synthetic ...
Introduction: Tumor-derived heat shock protein (HSP)-peptide complexes (HSPPCs) induced immunity against malignancies in preclinical trials, working across tumor types and bypassing the need to identify single immunogenic peptides. These results paved the way for the use of human gp96 obtained from autologous tumor samples as an anti-cancer vaccine. Areas covered: Autologous tumor-derived HSP gp96 peptide complex (HSPPC-96) vaccine is emerging as a tumor- and patient-specific cancer vaccine, with confirmed activity in several malignancies. It has been tested in Phase III clinical trials in advanced melanoma and kidney cancer with evidence for efficacy in patients with earlier stage disease. HSPPC-96-based vaccine demonstrated an excellent safety profile, thus emerging as a novel therapeuti...
The atmospheric processing by ozone of peptide-containing mixed particles was investigated as proxies for biogenic and sea spray primary organic aerosol. Reactions were performed in a flow reactor and particle composition was monitored by photoelectron resonance capture ionization aerosol mass spectrometry. Mixed particles containing dipeptides in a saturated organic matrix of stearic and palmitic acids showed no reaction under ozonolysis at exposure levels of 2.5???10?4?atm s O3. However reactions of mixed particles of a dipeptide (Leu-Leu) in an unsaturated matrix (oleic acid) under the same conditions resulted in a rapid loss of the peptide ion signal, as well as the carrier matrix, and appearance of a number of ion signals corresponding to secondary products. High molecular weight imid...
Analyses of food-borne pathogens are of great importance in order to minimize the health risk for customers. Thus, very sensitive and rapid detection methods are required. Current conventional culture techniques are very time consuming. Modern immunoassays and biochemical analysis also require pre-enrichment steps resulting in a turnaround time of at least 24 h. Biomagnetic separation (BMS) is a promising more rapid method. In this study we describe the isolation of high affine and specific peptides from a phage-peptide library, which combined with BMS allows the detection of Salmonella spp. with a similar sensitivity as that of immunomagnetic separation using antibodies.
Many organic compounds can be adsorbed onto the interface of a metal and solution to form a thin film that inhibits the corrosion process according to a blocking and/or negative catalytic effect. Using the Langmuir-Blodgett (LB) technique, stearic acid (SA) monolayers were deposited onto the surface of an iron (Fe) electrode to study the inhibition effect and the mechanism of SA in a neutral medium. Molecular orientation and the number of deposited monolayers of SA were shown to have marked effects on inhibition of Fe corrosion. The inhibition mechanism depended mainly on blocking.
Purpose - The purpose of this paper is to evaluate the corrosion inhibition potential of mangrove (Rhizopora apiculata) tannin in hydrochloric acid medium on copper with the view of developing a natural corrosion inhibitor. Design/methodology/approach - The mangrove tannin was extracted from the mangrove bark and its anticorrosion potential was studied by weight loss, electrochemical and scanning electron microscopy (SEM) analysis. Findings - It has been found that the mangrove tannin effectively inhibits the corrosion on copper metal in hydrochloric acid solution. The results of the electrochemical and weight loss methods showed that the inhibition efficiency of mangrove tannin increases with increasing its concentration. Inhibition is achieved through the adsorption of tannin molecules o...
Effector proteins expressed in the esophageal gland cells of cyst nematodes are delivered into plant cells through a hollow, protrusible stylet. Although evidence indicates that effector proteins function...Full Text Available
The acyl coenzyme A (CoA) binding protein AcbA is secreted unconventionally and processed into spore differentiation factor 2 (SDF-2), a peptide that coordinates sporulation in Dictyostelium...Full Text Available
AbstractThere is an urgent need for innovative therapies against ovarian cancer, one of the leading causes of death from gynecological cancers in the United States. Immunotherapy employing...Full Text Available
1. Seven unique carboxymethylcysteine-containing peptides have been isolated from tryptic digests of rabbit muscle aldolase carboxymethylated with iodo[2-14C]acetic acid in 8m-urea....Full Text Available
OBJECTIVETo determine if ProL1, a member of the opiorphin family of genes, can modulate erectile physiology, as it encodes a peptide which acts as...Full Text Available
We have performed multicanonical Monte Carlo simulations of C-peptide of ribonuclease A. It is known by CD and NMR experiments that this peptide has high alpha-helix content in aqueous solution and that the side-chain charges of residues Glu-2$^-$ and His-12$^+$ play an important role in the stability of the alpha-helix. In order to confirm these experimental implications, we have used two analogues of the peptide with charged and neutral side chains of Glu-2 and His-12. Two dielectric functions, distance-dependent and constant, are considered to study the effects of solvent contributions. All the simulations were started from random initial conformations. Various thermodynamic quantities such as average helicity as a function of residue number and average distance between two side chains as a function of temperature are calculated. The results are found to be in accord with the implications of CD and NMR experiments. The ...
To capitalize on the response of tumor cells to ionizing radiation, we developed a controlled-release nanoparticle drug delivery system using a targeting peptide that recognizes a radiation-induced...Full Text Available
In this work, we explore the potential of the metalloendopeptidase Lys-N for MALDI-MS/MS proteomics applications. Initially we digested a HEK293 cellular lysate with Lys-N and, for comparison, in parallel...Full Text Available
The neonatal Fc receptor FcRn provides IgG molecules with their characteristically long half-lives in vivo by protecting them from intracellular catabolism and then returning them to...Full Text Available
BackgroundBaculovirus, which has a width of 40 nm and a length of 250-300 nm, can display functional peptides, receptors and antigens on its surface by their fusion with a baculovirus...Full Text Available
The parathyroid hormone receptor (PTHR) is a class B G protein-coupled receptor that plays critical roles in bone and mineral ion metabolism. Ligand binding to the PTHR involves interactions to both...Full Text Available
Secreted human bronchial mucins, directly collected from macroscopically healthy bronchial mucosa, were prepared in the presence of six proteinase inhibitors, and analysed by electron microscopy. These...Full Text Available
Severe acute respiratory syndrome (SARS) is an infectious disease caused by a novel coronavirus that cost nearly 800 lives. While there have been no recent outbreaks of the disease, the threat...Full Text Available
Human skin is a local source of corticotropin-releasing hormone (CRH) and expresses CRH and CRH receptors (CRH-R) at mRNA and protein levels. Epidermal melanocytes respond to CRH by induction...Full Text Available
We have developed a method for dissecting single neurons from the nematode Ascaris suum, in order to determine their peptide content by mass spectrometry (MS). In this paper,...Full Text Available
Gastrin-releasing peptide receptor (GRPR), a member of the G protein-coupled receptor superfamily, has been utilized for receptor-mediated targeting of imaging and therapeutic agents; here we extend...Full Text Available
Type 2 diabetes mellitus (T2DM) results from insulin resistance and β-cell dysfunction, in the setting of hyperglucagonemia. Glucagon is a 29 amino acid peptide hormone, which is secreted from...Full Text Available
In the synthesis of the peptidyl-polymer corresponding to the sequence (57-100) of the ..beta.. chain of human hemoglobin on Teflon with radiationally grafted polystyrene a comparative study was made of different methods of fragment condensation. It was shown that the most effective methods are azide condensation and condensation with the use of complex F.
In the synthesis of the peptidyl-polymer corresponding to the sequence (57-100) of the #beta# chain of human hemoglobin on Teflon with radiationally grafted polystyrene a comparative study was made of different methods of fragment condensation. It was shown that the most effective methods are azide condensation and condensation with the use of complex F.
A monensin-sensitive ruminal peptostreptococcus was able to grow rapidly (growth rate of 0.5/h) on an enzymatic hydrolysate of casein, but less than 23% of the amino acid nitrogen was ever utilized....Full Text Available
The carboxyl-terminal region of tubulin alpha and beta subunits plays a major role in regulating its assembly into microtubules and constitutes an essential domain for the selective interaction of microtubule-associated...Full Text Available
BackgroundThe successful interaction of bacterial pathogens with host tissues requires the sensing of specific chemical and physical cues. The human gut contains a huge number of...Full Text Available
OBJECTIVEPreimplantation factor (PIF) is a novel, 15 amino acid peptide, secreted by viable embryos. This study aims to elucidate PIF’s effects in human endometrial...Full Text Available
A pentapeptide open reading frame equipped with a canonical ribosome-binding site is present in the Escherichia coli 23S rRNA. Overexpression of 23S rRNA fragments containing the mini-gene renders cells...Full Text Available
During complementary chromatic adaptation (CCA), cyanobacterial light harvesting structures called phycobilisomes are restructured in response to ambient light quality shifts. Transcription of genes...Full Text Available
Humanin (HN), a 24-residue peptide, was identified as a novel neuroprotective factor and shows anti-cell death activity against a wide spectrum of Alzheimer's disease (AD)-related cytotoxicities, including...Full Text Available
Nine secondary metaboites of cyclic peptide were isolated from three mangrove endophytic fungi Paecilomyces sp. (treel-7), 4557,ZZF65. They were viscumamide(1),cyclo(Pro-Iso)(2),cyclo(Phe-Gly)(3),cyclo(Phe-Ana)(4),cyclo(Gly-Pro) (5),cyclo(Gly-Leu)(6), cyclo(Trp-Ana)(7),neoechinulin A(8),cyclo(Pro-Thr)(9). The compounds 1,7,8,9 were firstly isolated from marine fungus. PMID:18422185
Nop25 is a putative RNA binding nucleolar protein associated with rRNA transcription. The present study was undertaken to determine the mechanism of Nop25 localization in the nucleolus. Deletion experiments of Nop25 amino acid sequence showed Nop25 to contain a nuclear targeting sequence in the N-terminal and a nucleolar targeting sequence in the C-terminal. By expressing derivative peptides from the C-terminal as GFP-fusion proteins in the cells, a lysine and arginine residue-enriched peptide (KRKHPRRAQDSTKKPPSATRTSKTQRRRR) allowed a GFP-fusion protein to be transported and fully retained in the nucleolus. When the peptide was fused with cMyc epitope and expressed in the cells, a cMyc epitope was then detected in the nucleolus. Nop25 did not localize in the nucleolus by deletion of the peptide from Nop25. Furthermore, deletion of a subdomain (KRKHPRRAQ) in the peptide or amino acid ...
We use a novel normal mode analysis of an elastic network model drawn from configurations generated during microsecond all-atom molecular dynamics simulations to analyze the mechanism of auto-inhibition...Full Text Available
Latent inhibition (LI) manifests as poorer conditioning to a CS that has previously been presented without consequence. There is some evidence that LI can be potentiated by reduced mesoaccumbal dopamine...Full Text Available
Protection afforded by trialkyl phosphorothionates against the lung injury caused by trialkyl phosphorothiolates probably results from the inhibition by the P = S moiety of the thionates, of one or...Full Text Available
Mycophenolate mofetil (MMF) is an immunosuppressive drug that acts as a selective inhibitor of inosine monophosphate dehydrogenase (IMPDH). MMF has recently been shown to inhibit the enzymatic activity...Full Text Available
MicroRNAs (miRNAs) are endogenously encoded small noncoding RNAs, derived by processing of short RNA hairpins, that can inhibit the translation of mRNAs bearing partially complementary target sequences....Full Text Available
Method for inhibiting the formation of foulants on petrochemical equipment which involves adding to the petrochemical, during processing, a composition comprising a thiodipropionate and either a dialkyl acid phosphate ester or a dialkyl acid phosphite ester.
Spike-timing-dependent plasticity (STDP), a form of Hebbian plasticity, is inherently stabilizing. Whether and how GABAergic inhibition influences STDP is not well understood. Using a model neuron driven...Full Text Available
3-Deazaadenosine (deazaAdo) inhibits lymphocyte-mediated cytolysis in vitro at micromolar concentrations and is potentiated markedly in this activity by L-homocysteine thiolactone....Full Text Available
As the result of genetic alterations and tumor hypoxia, many cancer cells avidly take up glucose and generate lactate through lactate dehydrogenase A (LDHA), which is encoded by a target gene of c-Myc...Full Text Available
In regions of high bone loading, the mechanoresponsive osteocytes inhibit osteoclastic bone resorption by producing signaling molecules. One possible candidate is matrix extracellular phosphoglycoprotein...Full Text Available
Spontaneous radiation by an atom in a Rydberg state is inhibited by use of parallel conducting planes to eliminate the vacuum modes at the transition frequency. Spontaneous radiation emission is observed to turn off abruptly at the cutoff frequency of the waveguidelike structure, and the natural lifetime is measured to increase by a factor of at least 20.
INTRODUCTION:Gynura procumbens has been shown to decrease blood pressure via inhibition of the angiotensin‐converting enzyme. However, other mechanisms that...Full Text Available
The structural features required for xyloglucan oligosaccharides to inhibit 2,4-dichlorophenoxyacetic acid-stimulated elongation of pea stem segments have been investigated. A nonasaccharide (XG9)...Full Text Available
BackgroundMany studies associated the main polyphenolic constituent of green tea, (-)-Epigallocatechin-3-gallate (EGCG), with inhibition of cancers, invasion and metastasis. To date,...Full Text Available
Methyl fluoride is frequently used to specifically inhibit acetoclastic methanogenesis, thus allowing determination of the relative contribution of acetate versus H2/CO2 to total...Full Text Available
Chlorazole fast pink 2BL inhibited the classical complement pathway in rat serum both in vivo and in vitro. The in vitro potency of chlorazole fast pink against the alternative pathway could not be...Full Text Available
Mechanism-based inhibition of cytochrome P450 (CYP) 3A4 is characterized by NADPH-, time-, and concentration-dependent enzyme inactivation, occurring when some drugs are converted by CYPs to reactive...Full Text Available
BackgroundInadequate platelet inhibition despite aspirin and clopidogrel therapy during and after a percutaneous coronary intervention is associated with an impaired clinical outcome....Full Text Available
Tetherin (BST2/CD317) has been recently recognized as a potent interferon-induced antiviral molecule that inhibits the release of diverse mammalian enveloped virus particles from infected cells. By...Full Text Available
Low concentrations of sugars altered the sensitivity of seed germination to inhibition by exogenous abscisic acid (ABA). Germination of wild-type and ABA-insensitive (abi) Arabidopsis...Full Text Available
Pollen from four temperate-latitude taxa were treated with UV radiation in a portion of the UV-B (280-320 nm) waveband during in vitro germination. Inhibition of germination was noted in this pollen compared to samples treated identically except for the exclusion of the UV-B portion of the spectrum. Levels similar to maximum solar UV-B found in temperate-latitude areas failed to inhibit pollen germination significantly, while levels similar to maximum solar UV-B found in equatorial alpine locations caused partial inhibition of germination in three of the four taxa examined.
The adsorption and corrosion inhibition behavior of three selected thiosemicarbazone derivatives, namely 3-pyridinecarboxaldehyde thiosemicarbazone (META), isonicotinaldehyde thiosemicarbazone (PARA) and 2-pyridinecarboxaldehyde thiosemicarbazone (ORTHO) at the nickel surface were studied electrochemically by Tafel and impedance methods and computationally by carrying out Monte Carlo searches of configurational space on nickel/thiosemicarbazone derivative system. Electrochemical measurements showed that the inhibition efficiency of these compounds increased with increase in their concentration. The recorded inhibition efficiencies of the three tested thiosemicarbazone increase in the order: META>PARA>ORTHO. Polarization studies showed that these compounds act as mixed-type inhibitors for n...
Azobenzene dyes are effective inhibitors for austenitic 304 L and 316 L stainless steel corrosion in high acidic medium up to 7N. A good efficiency is obtained from weight loss and electrochemical Rsub(p) measurements in hydrochloric acid, while no inhibition is observed in sulfuric solutions. Transformation from the primarily azobenzene to other compounds give rise to enhanced protection of steel samples, and probable structures of the inhibiting species are proposed in view of our results.
Azobenzene dyes are effective inhibitors for austenitic 304 L and 316 L stainless steel corrosion in high acidic medium up to 7N. A good efficiency is obtained from weight loss and electrochemical Rsub(p) measurements in hydrochloric acid, while no inhibition is observed in sulfuric solutions. Transformation from the primarily azobenzene to other compounds give rise to enhanced protection of steel samples, and probable structures of the inhibiting species are proposed in view of our results.
The sequence segment 181-200 of the Torpedo nicotinic acetylcholine receptor (nAChR) #alpha#subunit forms a binding site for #alpha#-bungarotoxin (#alpha#-BTX). Synthetic peptides corresponding to the homologous sequences of human, calf, mouse, chicken, frog, and cobra muscle nAChR #alpha#1 subunits were tested for their ability to bind "1"2"5I-#alpha#-BTX, and differences in #alpha#-BTX affinity were determined by using solution (IC_5_0s) and solid-phase (K_ds) assays. Panels of overlapping peptides corresponding to the complete #alpha#1 subunit of mouse and human were also tested for #alpha#-BTX binding, but other sequence segments forming the #alpha#-BTX site were not consistently detectable. The role of a putative vicinal disulfide bound between Cys-192 and -193, relative to the Torpedo sequence, was determined by modifying the peptides with sulfhydryl reagents. Reduction and alkylation of the ...
An improved labeling procedure for peptides attached to organometallic 99mTc(III) '4+1' mixed-ligand complexes in which the radiometal is coordinated by a tripodal tetradentate chelator 2,2',2''-nitrilotriethanethiol (NS3) and a monodentate isocyanide ligand is presented. The labeling procedure was evaluated by the synthesis of [99mTc(NS3)(L2-RGD)]. The containing radiopharmaceutically interesting RGD-peptide cyclo[Arg-Gly-Asp-D-Tyr-Lys] was modified with 4-isocyanobutanoic acid (L2) as linker conjugated to N6-Lys to get the monodentate ligand L2-RGD. The structural identity of the 99mTc-conjugate was confirmed by comparison to a Re reference compound. The Tc- and Re-conjugates had matching retention times under identical HPLC conditions. The 99mTc-labeling was performed in a novel one-step procedure using the eluate of a 99Mo/99mTc generator, NS3, the isocyanide modified peptide, SnCl2, Na2EDTA, mannitol and ascorbic acid ...
Designer natriuretic peptides (NPs) represent an active area of drug development. In canine and human studies, the designer natriuretic peptide CD-NP demonstrated more desirable therapeutic potential than recombinant B-type NP (BNP), which is known as nesiritide and is approved for treatment of acute decompensated heart failure. However, why CD-NP is more effective than BNP is not known. We previously reported that CD-NP is a poorer activator of human guanylyl cyclase-A (GC-A) and a better activator of human guanylyl cyclase-B than BNP. Here, guanylyl cyclase bioassays were used to compare the susceptibility of CD-NP verses ANP, BNP, CNP and DNP to inactivation by human kidney membranes. The half time (t(1/2)) for CD-NP inactivation was increased by factors of 13, 3 and 4 compared to ANP, BNP and CNP, respectively, when measured in the same assay. Surprisingly, DNP failed to undergo complete inactivation and was the most degradation resistant ...
The presence of endothelin (ET)-like immunoreactivity and the cardiovascular effects of mammalian ET-1 in fish have been reported. To identify ET-related peptides in fish, we screened the cDNA library of the salmon (Oncorhynchus keta) stomach by means of rapid amplification of cDNA ends, and we cloned cDNAs encoding an ET-related peptide. The salmon ET-related sequence of 21 amino acids is identical to the trout ET-1 peptide recently purified from kidney specimens of Oncorhynchus mykiss. The deduced amino acid sequence of salmon pre-proET-1 (PPET-1) comprises 244 amino acids, including a putative signal sequence and mature ET-1, as well as big ET-1 and ET-1-like sequences. This precursor, the first reported PPET-1 sequence for Salmoniformes, Teleostei, has low homology with the sequences of human, mouse, frog (Xenopus laevis), and zebrafish (Danio rerio) PPET-1 (26%, 29%, 24%, and 39%, respectively). PMID:16740985
Zinc-fingers, which widely exist in eukaryotic cell and play crucial roles in life processes, depend on the binding of zinc ion for their proper folding. To computationally study the zinc coupled folding of the zinc-fingers, charge transfer and metal induced protonation/deprotonation effects have to be considered. Here, by attempting to implicitly account for such effects in classical molecular dynamics and performing intensive simulations with explicit solvent for the peptides with and without zinc binding, we investigate the folding of the Cys2His2 type zinc-finger motif and the coupling between the peptide folding and zinc binding. We find that zinc ion not only stabilizes the native structure, but also participates in the whole folding process. It binds to the peptide at early stage of folding, and directs or modulates the folding and stabilizations of the component beta-hairpin and alpha-helix. Such a crucial role of ...
The recent development of matrix-assisted UV laser desorption (LD) mass spectrometry has made possible the ionization and detection of extremely large molecules (with molecular weights exceeding 100,000 Daltons). This technique has generated enormous interest in the biological community for the direct examination of large peptides and oligonucleotides. Although this matrix-assisted ionization method has been developed and used almost exclusively with time-of-flight (TOF) mass spectrometers, research is currently in progress to demonstrate this technique with trapped ion mass spectrometers, such as Fourier transform ion cyclotron resonance mass spectrometry (FTMS). The potential capabilities of FTMS for wide mass range, high resolution measurement, and ion trapping experiments suggest that this instrumental technique should be useful for the detailed structural characterization of large ions generated by the matrix-assisted technique. We have recently demonstrated ...
The photoelectron resonance capture ionization (PERCI) of cysteine (Cys) and small gas-phase neutral peptides that contain the Cys residue (Cys-Gly, g-Glu-Cys, and glutathione (g-Glu-Cys-Gly)) is reported. At an ionization energy less than 1eV two types of dissociative electron attachment ionization were observed for Cys: hydrogen atom loss, resulting in formation of the ion [Cys-H]-, and dissociation of the CH2-SH bond, resulting in formation of the ion [SH]-. The presence of these ions suggests that both the p*(-CO2H) and *(C-S) orbitals can act as low energy electrophores on Cys. This ionization trend was observed for the dipeptides Cys-Gly and g-Glu-Cys as well as glutathione, with evidence that dissociation of the CH2-SH bond in these peptides can also result in ions of the form [M-SH...
The antimicrobial peptide scygonadin (Scy) was first isolated from the gonad of Scylla serrata and its gene is predominantly expressed in the ejaculatory duct of adult males. Thus, its function was predicted to be associated with reproductive immunity, but this is still unclear and needs further investigation. In our study, the expression pattern of Scy at different developmental stages of both male and female S. paramamosain was investigated, so that the potential function of this peptide could be examined. Using real-time quantitative PCR, Scy mRNA transcripts were demonstrated obviously in the vulnerable embryos and larvae-zoea I but very weakly detected in the larvae-zoea III, megalops and juveniles. The gene expression pattern showed a decreasing trend during the early developmental s...
Two peptide ligands conjugated adenine, [9-N-(tritylmercapto acetyl diglycyl aminoethyl) adenine, Tr-MAG_2-Ade] and [9-N-(tritylmercapto acetyl triglycyl aminoethyl) adenine, Tr-MAG3-Ade], are synthesized and labeled with "9"9"mTc by directly labeling method. The stability of "9"9"mTc-MAG_2- adenine and "9"9"mTc-MAG_3-adenine in vitro is measured. The uptake radios of tumor to muscle at 3h post-injection are 5.70 and 4.92, respectively. The biodistribution and scintigraphic imaging studies show that the two complexes have high localization in tumor and high contrasted tumor images can be obtained, which suggest their potential utility as tumor imaging agents. But the high radioactivity of abdomen could prevent the tumor imaging in this area. (author)
Background/Objectives: Cardiotoxic drug poisoning can lead to severe cardiac shock (CS) and death. B-type natriuretic peptide (BNP) is a well-established diagnostic and prognostic marker in heart failure but has never been assessed in patients with cardiotoxic drug poisoning. The aim of the study was to determine whether BNP could be useful for early stratification of patients admitted to intensive care unit. Methods: 30 consecutive patients experiencing shock and cardiotoxic drug exposure were enrolled in a prospective monocentric study and underwent at least two BNP measurements within the first 24 h after admission. Results: While BNP values on admission were poorly informative, subsequent BNP measurements (11 +- 6 h after admission) were significantly increased in patients with CS comp...
Peptide sequences such as lysine-arginine-serine-arginine (KRSR) selectively bind transmembrane proteoglycans (e.g. heparin sulfate) of osteoblasts (bone-forming cells) and are, therefore, actively being investigated for orthopedic applications. Further, nanophase materials (or materials with grain or particle sizes less than 100 nm) are promising new materials that promote new bone growth more than compared to conventional (that is, micron grain or particle size) materials. To combine the above two promising approaches for improving orthopedic implants, the objective of this in vitro study was to functionalize titanium (Ti) surfaces (both nanophase and conventional) with KRSR peptides and study their osteoblast cell adhesive properties. Materials were characterized by X-ray photoelectron ...
A series of [60]fullerene-substituted phenylalanine (Baa) and lysine derivatives have been prepared by the condensation of 1,2-(4prime-oxocyclohexano)fullerene with the appropriately protected (4-amino)phenylalanine and lysine, respectively. Conversion of the imine to the corresponding amine is achieved by di-acid catalyzed hydroboration. The reduction of the imine is not accompanied by hydroboration of the fullerene cage. The [70]fullerene phenylalanine derivative has also been prepared as have the di-amino acid derivatives. The compounds were characterized by MALDI-TOF mass spectrometry, UV/Vis spectroscopy, and cyclic voltammetry. 1H and 13C NMR spectroscopy allowed the observation of diastereomers. Fullerene-substituted peptides may be synthesized on relatively large scale by solid-pha...
Abstract In 46 febrile neutropenic patients who had undergone haematopoietic stem cell transplantation, the fluorescence in situ hybridisation using peptide nucleic acid probes (PNA FISH), Gram stain/acridine orange leukocyte cytospin (Gram/AOLC), and differential time to positivity (DTP) methods were performed for detection of catheter related bloodstream infections (CRBSIs). As compared with the DTP method (which detected 11 patients with CRBSI), the PNA FISH and the Gram/AOLC methods detected ten of 11 CRBSI patients, resulting in a sensitivity, specificity, negative predictive value and positive predictive value of 91%, 100%, 97% and 100%, respectively, for the PNA FISH method as well as for the Gram/AOLC method.
Apelin is a peptide known as the ligand of the G-protein-coupled receptor APJ. Several active apelin forms exist such as apelin-36, apelin-17, apelin-13, and the pyroglutamated form of apelin-13. Apelin and APJ are expressed in the central nervous system, particularly in the hypothalamus and in many peripheral tissues. Apelin has been shown to be involved in the regulation of cardiovascular and fluid homeostasis, food intake, cell proliferation, and angiogenesis. In addition to be an ubiquitous peptide, apelin is also produced and secreted by adipocytes and thus considered as an adipokine. This has opened a new field of investigation establishing a link between apelin and metabolic disorders (obesity, type 2 diabetes, etc.) which is the focus of the present review. Several studies, but not...
Abstract in english Functional properties of soy proteins for food are closely related to the composition of their storage protein subunits. Using base excision sequence scanning (BESS), we show that the absence of the A4 peptide in the G4 glycinin subunit of the soybean (Glycine max L.) cultivar Enrei was caused by the same point mutation in the Gy4 gene as previously reported in the soybean cultivar Raiden. Although the genetic relationship between Raiden and Enrei is not known, the same p (more) oint mutation in their Gy4 genes may indicate that they probably share a related origin. The application of BESS to identify single nucleotide polymorphisms (SNPs) as co-dominant markers for marker-assisted selection (MAS) of a recessive null allele is also discussed.
In the present study, the immunomodulatory effect of {beta}-endorphin ({beta}-E) and shorter pro-opiomelancortin (POMC) fragments was evaluated by assessing their influence on respiratory burst in human polymorphonuclear leukocytes (PMN). The effect of the peptides on phorbol myristate acetate (PMA)-stimulated production of reactive oxygen metabolites was measured in a lucigenin-enhanced chemiluminescence (CL) assay. Both POMC peptides with opiate-like activity and their non-opioid derivatives were tested. With the exception of {alpha}-E, PMA-stimulated respiratory burst was suppressed by all POMC fragments tested. A U-shaped dose-response relation was observed. Doses lower than 10{sup {minus}17}M and higher than 10{sup {minus}8}M were without effect. {beta}-E and dT{beta}E both suppressed PMA-induced oxidative burst in human PMN at physiological concentrations. {gamma}-E and dT{gamma}E proved to be less potent inhibitors, reaching maximal ...
Spider venoms provide a highly valuable source of peptide toxins that act on a wide diversity of membrane-bound receptors and ion channels. In this work, we report isolation, biochemical analysis, and...Full Text Available
BackgroundOur previous studies indicate that either PEP-1-superoxide dismutase 1 (SOD1) or PEP-1-catalase (CAT) fusion proteins protects myocardium from ischemia-reperfusion-induced...Full Text Available
Several early genes of murine cytomegalovirus (MCMV) encode proteins that mediate immune evasion by interference with the major histocompatibility complex class I (MHC-I) pathway of antigen presentation...Full Text Available
The management of CNS tumors is limited by the blood-brain barrier (BBB), a vascular interface that restricts the passage of most molecules from the blood into the brain. Here we show that phage particles...Full Text Available
With the aim of an experimental check on the validity of the theory of molecular recognition, the authors have carried out the chemical-enzymatic synthesis and cloning of the gene of human calcitonin and also of the genes of antisense polypeptides to human calcitonin and miniproinsulin. It has been shown that recombinant plasmids obtained on the basis of these synthetic genes are capable of ensuring the biosynthesis of the given polypeptides in E. coli cells as hybrid proteins with the IgG-binding domain of staphylococcal protein A.
Transforming growth factor (TGF)-βs are secreted in large latent complexes consisting of TGF-β, its N-terminal latency-associated peptide (LAP) propeptide, and latent TGF-β...Full Text Available
A cDNA library was constructed from HL60 human promyelocyte poly(A)+ RNA harvested 3 h after induction of macrophage differentiation with 12-O-tetradecanoyl phorbol-13-acetate in the presence of cycloheximide....Full Text Available
The IgG response to gp41 (envelope glycoprotein of Mr 41,000) of the human immunodeficiency virus (HIV) was studied with eight synthetic peptides derived from three different regions of the protein....Full Text Available
Low-level lead exposure during early childhood has long been associated with altered neurocognitive development and diminished cognitive functions. Over nine thousand U.S. industrial facilities...Full Text Available
During protein synthesis, aminoacyl-tRNA (aa-tRNA) and release factors 1 and 2 (RF1 and RF2) have to bind at the catalytic center of the ribosome on the 50S subunit where they take part in peptide bond...Full Text Available
DescriptionIron deficiency anaemia is a common problem and may be particularly important to certain groups of vegetarians. This project investigates isolating and identifying iron-binding constituents of meat digests using human Caco-2 cell lines. Stable isotope techniques used to test whether one or more of these compounds enhance iron absorpion in vivo and could therefore be added to vegetarian products to imporve iron nutrition.
TH1 cytokine secretion was examined in response to synthetic peptides of the 85A component of the major secreted, fibronectin-binding antigen 85 complex from Mycobacterium tuberculosis in seven different...Full Text Available
BackgroundThe human endogenous retrovirus HERV-K(HML-2) family is associated with testicular germ cell tumors (GCT). Various HML-2 proviruses encode viral proteins such as Env and...Full Text Available
FMRFamide-related peptides (FaRPs) are a diverse and physiologically important class of neuropepeptides in the metazoa. In insects, FaRPs function as brain-gut neuropeptides and have been immunolocalized...Full Text Available
During this report period our research efforts have concentrated on studies of the dissociation reactions of model peptides and other biologically important molecules. In addition, a considerable amount of research effort has been directed toward improving the apparatus used for laser-ion beam photodissociation. The instrumental improvements include some changes on the original apparatus, but most of this effort involved designing a second generation laser-ion beam photodissociation instrument.
The affinity label 8-((4-bromo-2,3-dioxobutyl)thio)adenosine 5{prime}-triphosphate (8-BDB-TA-5{prime}-TP) reacts covalently with rabbit muscle pyruvate kinase, incorporating 2 mol of reagent/mol of enzyme subunit upon complete inactivation. Protection against inactivation is provided by phosphoenolpyruvate, K{sup +}, and Mn{sup 2+} and only 1 mol of reagent/mol of subunit is incorporated. The authors have now identified the resultant modified residues. After reaction with 8-BDB-TA-5{prime}-TP at pH 7.0, modified enzyme was incubated with ({sup 3}H)NaBH{sub 4} to reduce the carbonyl groups of enzyme-bound 8-BDB-TA-5{prime}-TP and to introduce a radioactive tracer into the modified residues. Following carboxymethylation and digestion with trypsin, the radioactive peptides were separated on a phenylboronate agarose column followed by reverse-phase high-performance liquid chromatography in 0.1% trifluoroacetic acid with an acetonitrile gradient. Gas-phase sequencing ...
Several examples of the 14-membered, para-bridged ring system of the cyclopeptide alkaloids have been synthesized via an active ester cyclization. The yield of monomeric cyclopeptide varied from 1 to 33% and was affected by the amino acid substitution pattern and amide conformation of the linear peptide precursors. Both the synthetic models and a naturally occurring cyclopeptide alkaloid, ceanothine B, bind monovalent (Li"+) and divalent (Ca"2"+, Mg"2"+) cations. 4 figures, 1 table.
This study focuses on the effects of long-term renin-angiotensin system suppression and/or incretin mimetic therapies on the regulation and binding affinity of GLP-1 to its receptor in the coronary...Full Text Available
Epidermal growth factor (EGF) stimulates adenylyl cyclase in the heart via activation of the stimulatory GTP-binding protein Gs. Therefore, employing peptides corresponding to regions in the cytosolic...Full Text Available
We have purified and characterized two peptides, named KAaH1 and KAaH2 (AaH polypeptides 1 and 2 active on K+ channels, where AaH stands for Androctonus australis Hector),...Full Text Available
DNA polymerase gamma from purified nuclei of EMT-6 cells (mice) seems to be identical to the mitochondrial DNA polymerase from the same source following several criteria. These two enzyme activities are strongly inhibited by ethidium bromide and acriflavin, while proflavin, acridine orange, daunomycin and chloroquine inhibition is less pronounced. In the case of DNA polymerases alpha and beta very little inhibition by ethidium bromide was observed. Intercalation of this dye in a poly dA-dT 12-18 template-primer was studied spectrophotometrically under conditions similar to those in the in vitro DNA polymerase assay. The polymerase assay. The inhibition by this drug of the mitochondrial DNA polymerase gamma activity was shown to be competitive at varying concentrations of TTP while the inhibition was of the non-competitive type at different concentrations of poly dA-dT 12-18. We ...
In vivo effects of toxaphene on calcium pump activity in rat brain synaptosomes was studied. Male Sprague-Dawley rats were dosed with toxaphene at 0,25,50, and 100 mg/kg/day for 3 days and sacrificed 24 h after last dose. Ca/sup 2 +/-ATPase activity and /sup 45/Ca uptake were determined in brain P/sub 2/ fraction. Toxaphene inhibited both Ca/sup 2 +/-ATPase activity and /sup 45/Ca/sup 2 +/ uptake and the inhibition was dose dependent. Both substrate and Ca/sup 2 +/ activation kinetics of Ca/sup 2 +/-ATPase indicated non-competitive type of inhibition as evidenced by decreased catalytic velocity but not enzyme-substrate affinity. The inhibited Ca/sup 2 +/-ATPase activity and Ca/sup 2 +/ uptake were restored to normal level by exogenously added calmodulin which increased both velocity and affinity. The inhibition of Ca/sup 2 +/-ATPase activity and Ca/sup 2 +/ uptake and restoration by ...
In vivo effects of toxaphene on calcium pump activity in rat brain synaptosomes was studied. Male Sprague-Dawley rats were dosed with toxaphene at 0,25,50, and 100 mg/kg/day for 3 days and sacrificed 24 h after last dose. Ca"2"+-ATPase activity and "4"5Ca uptake were determined in brain P_2 fraction. Toxaphene inhibited both Ca"2"+-ATPase activity and "4"5Ca"2"+ uptake and the inhibition was dose dependent. Both substrate and Ca"2"+ activation kinetics of Ca"2"+-ATPase indicated non-competitive type of inhibition as evidenced by decreased catalytic velocity but not enzyme-substrate affinity. The inhibited Ca"2"+-ATPase activity and Ca"2"+ uptake were restored to normal level by exogenously added calmodulin which increased both velocity and affinity. The inhibition of Ca"2"+-ATPase activity and Ca"2"+ uptake and restoration by calmodulin suggests that toxaphene may impair active ...
Inhibition efficiency of some water-soluble hydrazones for C-steel corrosion in hydrochloric acid has been tested by weight loss, polarisation measurements and open circuit technique. The inhibition effect was attributed to the adsorption of the additives on the C-steel surface as supported by adsorption measurements at Pt electrode using cyclic voltammetry. Electrochemical measurements indicated that all the additives behave as cathodic-type inhibitors. The data obtained fit well to both the Temkin adsorption isotherm and the kinetic-thermodynamic model. The inhibition behaviour and its order were explained with the help of the proposed skeletal representation.
Botulinum neurotoxin is produced by the bacterium, Clostridium botulinum. The neurotoxin inhibits acetylcholine at the neuromuscular junction, thus interfering with overall muscular contraction. Botulinum neurotoxin is commonly used for the following medical conditions: cervical dystonia, upper limb spasticity, blepharospasm, strabismus, and hyperhydrosis. However, the use of botulinum neurotoxin was recently approved for the prophylaxis of headaches in adults with chronic migraines. The proposed mechanism of botulinum neurotoxin is no longer solely limited to the inhibition of acetylcholine. There are new mechanisms emerging that involve inhibition of proinflammatory agents and neuropeptides involved in chronic pain. Consequently, there is a disruption of the overall sensory feedback loop...
SUMMARYHomeostatic synaptic plasticity is a negative feedback mechanism neurons use to offset excessive excitation or inhibition by adjusting their synaptic strengths. Recent...Full Text Available
The muscarinic receptor binding of trazodone, a new nontricyclic antidepressant, was compared with established tricyclic antidepressants. The ability to inhibit the binding of [3H]-quinuclidinyl benzilate...Full Text Available
Corrosion inhibition of iron in H2SO4 by polyacrylic acid (PAA) was investigated using electrochemical techniques at 30degreeC. Results obtained indicate that PAA inhibited the corrosion of iron in the acid medium. Inhibition efficiency increases with increase in PAA concentration and synergistically enhanced on addition of iodide ions. Potentiodynamic polarization results suggest that PAA functions as a modest cathodic inhibitor. The adsorption of PAA onto the iron surface followed Temkin adsorption isotherm. FTIR analysis revealed that the synergistic effect due to co-adsorption of iodide ions and PAA is co-operative in nature.
Regulatory T cells are proposed to play a central role in the maintenance of immunological tolerance in the periphery, and studies in many animal models demonstrate their capacity to inhibit inflammatory...Full Text Available
Phospholipase D (PLD) has been recognized as a regulator of cell proliferation and tumorigenesis, but little is known about the molecules regulating PLD expression. Thus, the identification of small molecules inhibiting PLD expression would be an important advance in PLD-mediated physiology. Quercetin, a ubiquitous bioactive flavonoid, is known to inhibit proliferation and induce apoptosis in a variety of cancer cells. In the present study, we examined the effect of quercetin on the expression of PLD in U87 glioma cells. Quercetin significantly suppressed the expression of PLD1 at the transcriptional level. Moreover, quercetin abolished the protein expression of PLD1 in a time and dose-dependent manner, as well as inhibited PLD activity. Quercetin suppressed NFkB-induced PLD1 expression vi...
The binding of iodine-labelled plasminogen to Helicobacter pylori CCUG 17874 was characterized. Inhibition of the binding was observed after preincubation of H. pylori...Full Text Available
The effect of low concentrations of nalidixic acid on ribonucleic acid (RNA) synthesis in Escherichia coli was examined. It was observed that RNA synthesis in exponentially growing...Full Text Available
This paper presents the corrosion inhibition performance of soluble self-doped copolymers of aniline and 4-amino-3-hydroxy-naphthalene-1-sulfonic acid synthesized by chemical oxidative polymerization method. The corrosion inhibition behaviour of the copolymers in 1.0M HCl has been evaluated using Tafel Extrapolation method and electrochemical impedance spectroscopy (EIS) which was also used to propose the mechanism besides surface morphology. The results showed that the copolymer film exhibited the significant shifting in the corrosion potential and greater charge transfer resistance. The corrosion inhibition efficiency was found to increase from 50% to 90% by increasing the concentration of copolymer from 10 to 70mg/l in HCl medium. Moreover, the copolymer showed the larger degree of surf...
The antibacterial activities of different nitroheterocyclic compounds were assessed by an agar dilution method against aerobic, microaerophilic, and anaerobic bacteria. Nitronaphthofurans inhibited...Full Text Available
Carboxylesterases (CE) are ubiquitous enzymes that hydrolyze numerous ester-containing xenobiotics, including complex molecules, such as the anticancer drugs irinotecan (CPT-11) and capecitabine...Full Text Available
Hypoxia causes abnormal neonatal pulmonary artery remodeling (PAR) and inhibition of alveolar development (IAD). Transforming growth factor (TGF)-β is an important regulator of lung development...Full Text Available
The inhibition of DDT [1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane] dehydrochlorinase and glutathione S-aryltransferase by diphenylmethane and triphenylmethane...Full Text Available
1. Several ring-substituted derivatives of diphenyleneiodonium catalyse the exchange of Cl- and OH- ions across the inner membrane of rat liver mitochondria. They also inhibit state 3 and state 3u oxidations...Full Text Available
Mineral oil based power transmitting fluids, such as automatic transmission fluids, are disclosed which contain 0.05 to 2.0 weight percent of an ester of a thio-bis alkanol and a C/sub 12/-C/sub 50/ hydrocarbon succinic acid or anhydride, the ester being a multifunctional additive providing the properties of friction modification, corrosion inhibition, anti-wear, oxidation inhibition and extreme pressure properties to the fluids.
Detached first leaves of 3-day-old corn seedlings (Zea mays L. W64AxW183E) were incubated with nitrate in air or 100% O2 in the light. Nitrate accumulation in the leaves...Full Text Available
Pharmacological activation of group II metabotropic glutamate (mGlu2 and mGlu3) receptors inhibits reward-seeking behavior and/or rewarding efficacy induced by drugs (cocaine, nicotine) or natural...Full Text Available
NH4+inhibition kinetics for CH4 oxidation were examined at near-atmospheric CH4 concentrations in three upland forest soils. Whether NH4+-independent...Full Text Available
We have shown previously that raising extracellular Ca2+ inhibited the apical 70-pS K channel in the thick ascending limb (TAL; Wang, W.H., M. Lu, and S.C. Hebert. 1996. Am....Full Text Available
ObjectivesThe aim of this study was to comprehensively evaluate the antibacterial activity and MurE inhibition of a set of N-methyl-2-alkenyl-4-quinolones found...Full Text Available
Roots of maize (Zea mays L.) seedlings continue to grow at low water potentials that cause complete inhibition of shoot growth. In this study, we have investigated the role of abscisic...Full Text Available
The effect of WC particle size with the addition of VC as a grain growth inhibitor was investigated during the liquid phase sintering of WC-Co system. With increasing WC particle size at the same VC content, the effect of grain growth inhibition was increased. Also, with increasing the VC content, the grain shape of WC was changed from the faceted shape to the distorted shape, and the step density of the WC grain was increased. (orig.)
The addition of 0.0005-0.5 weight% linoleic acid trimer to synthetic motor fuels composed of 95.0-99.8% technical-grade alcohol (EtOH or MeOH) and 0.2-5.0% water inhibits the corrosion induced by the impurities, such as aliphatic acids 0.5-10.0, aliphatic aldehydes 0.5-10.0, and aliphatic esters 0.5-10 mg/100 ml alcohol.
The authors investigated the effect of T-2 toxin on rat liver mitochondrial protein synthesis. Isolated rat liver mitochondria were supplemented with an S-100 supernatant from rat liver and an external ATP-generating system. An in-vitro assay employing cycloheximide, and inhibitor of cytoplasmic protein synthesis, and chloramphenicol, and inhibitor of mitochondrial protein synthesis, to distinguish mitochondrial protein synthesis from the cytoplasmic process. Amino acid incorporation into mitochondria was dependent on the concentration of mitochondria and was inhibited by chloramphenicol. The rate of uptake of tritium leucine into mitochondrial protein was unaffected by the addition of T-2 toxin and was not a rate-limiting step in incorporation. However, 0.02 micrograms/ml of T-2 toxin decreased the rate of protein synthesis inhibition correlated with the amount of T-2 toxin taken up by the mitochondria. While T-2 toxin is known to ...
Conditioned medium from Sertoli cells, prepared from testes of 20-day-old rats, contains component(s) that inhibit the incorporation of (3H)-thymidine into DNA of peritubular myoid cells (PMC) and inhibit the proliferation of PMC. These components are trypsin-resistant, heat-stable compounds having a molecular weight less than 30,000. The active inhibitory components in Sertoli cell conditioned medium are inactivated by treatment with heparinase, but not by treatment with hyaluronidase or chondroitin sulfate lyases. Addition of heparin or heparan sulfate results in inhibition of DNA synthesis by PMC in a dose-dependent manner, whereas other glycosaminoglycans (GAGs) examined (hyaluronic acid, keratan sulfate, and chondroitin sulfate) have no detectable effects. Heparin and heparan sulfate are unique among GAGs tested in inhibiting the characteristic multilayer growth pattern of PMC following the ...
Probiotic agents, live microorganisms with beneficial effects for the host, may offer an alternative to conventional antimicrobials in the treatment and prevention of enteric infections. The probiotic agents Lactobacillus plantarum 299v and Lactobacillus rhamnosus GG quantitatively inhibited the adherence of an attaching and effacing pathogenic Escherichia coli to HT-29 intestinal epithelial cells but did not inhibit adherence to nonintestinal HEp-2 cells. HT-29 cells were grown under conditions that induced high levels of either MUC2 or MUC3 mRNA, but HEp-2 cells expressed only minimal levels of MUC2 and no MUC3 mRNA. Media enriched for MUC2 and MUC3 mucin were added exogenously to binding assays and were shown to be capable of inhibiting enteropathogen adherence to HEp-2 cells. Incubation of L. plantarum 299v with HT-29 cells increased MUC2 and MUC3 mRNA expression levels. From these in vitro studies, we propose the ...
A laboratory-scale well-mixed thermostatic reactor with continuously blasting air was used to investigate the oxidation inhibition of sulfite in dual alkali flue gas desulfurization (FGD) system. The effects of operating parameters such as pH value and catalyst concentration on the oxidation were studied. Sodium thiosulfate was used in the system, and was found that it significantly inhabited the sulfite oxidation. In the absence of catalyst, sodium thiosulfate at 12.67 mmol/L had an inhibition efficiency of approximately 98%. While in the presence of catalyst, sodium thiosulfate at 26.72 mmol/L had an inhibition efficiency less than 85.0%. The oxidation reaction order of sulfite in the sodium thiosulfate was determined to be -1.90 and -0.55 in the absence and presence of the catalyst, respectively. Apparent activation energy of oxidation inhibition was calculated to be 53.9 kJ/mol. Pilot tests showed ...
We cloned and characterized horse preproendothelin-2 (PPET-2) cDNA from intestinal tissue. The cDNA encoded 178 amino acids of the PPET-2 polypeptide, in which a 21-amino-acid mature endothelin-2 peptide and a 16-amino acid endothelin-2-like peptide were found. For the open reading frame the correspondence of horse PPET-2 cDNA with those of the ferret, human, dog, mouse and rat was 85.1%, 84.9%, 82.1%, 77.8% and 77.2%, respectively. Analysis of the organ distribution of PPET-2 mRNA by reverse transcription-polymerase chain reaction demonstrated that the kidney, stomach and small intestine are major sites of expression of the PPET-2 gene. Surprisingly, the mRNA is not detected in the large intestine, where high expression is demonstrated in the mouse and rat. This difference may result from the underlying functional differences of the large intestine between a herbivore (horse) and an omnivore (mouse and rat). PMID:15838341
Calcitonin gene-related peptide (CGRP) was localized by an immunocytochemical technique in the thyroid-parathyroid complexes of rat, guinea pig, rabbit, and in normal human thyroids and parathyroids. Human medullary carcinomas and parathyroid adenomas were also studied. In man and all animal species examined CGRP was present in the parafollicular cell, however, in guinea pigs only in small amounts. Except in rabbits, presence of CGRP was demonstrated in nerves of the thyroid and parathyroid capsule as well as in the nerve fibers of the capsular blood vessels. In the thyroid of guinea pigs CGRP was also noted in nerve fibers and in blood vessel walls between follicles. CGRP was also present in the parathyroid glands of rat and man, in nerve fibers localized between parathyroid cells. In rabbit the parafollicular cells between parathyroid cells also expressed CGRP immunoreactivity. No CGRP was noted in the parathyroids of the guinea pig. The proximity of parathyroid ...
The effects of atrial natriuretic peptide (ANP), oxytocin (OT) and vasopressin (AVP) on guanylate cyclase activity and cyclic GMP accumulation were examined, since these hormones appear to be intimately associated with blood pressure and intravascular volume homeostasis. ANP was found to increase cyclic GMP accumulation in ten cell culture systems, which were derived from blood vessels, adrenal cortex, kidney, lung, testes and mammary gland. ANP receptors were characterized in intact cultured cells using {sup 125}I-ANP{sub 8-33}. Specific {sup 125}I-ANP binding was saturable and of high affinity. Scratchard analysis of the binding data for all cell types exhibited a straight line, indicating that these cells possessed a single class of binding sites. Despite the presence of linear Scatchard plots, these studies demonstrated that cultured cells possess two functionally and physically distinct ANP-binding sites. Most of the ANP-binding sites in cultured cells have a ...
A novel single-chain immunotoxin was constructed by combining a CD33-specific single chain Fv (scFv) antibody fragment with an engineered variant of Pseudomonas exotoxin A (ETA). The variant toxin carries the KDEL peptide at its C-terminus, a cellular peptide mediating improved retrograde transport to the endoplasmic reticulum. The purified recombinant fusion protein induced potent apoptosis of the human myeloid cell lines U937, HL-60 and THP-1. Up to 98% of U937 cells were eliminated after treatment for 72 h with a single dose of 500 ng/ml (c. 7 nmol/l). Killing was antigen-specific and occurred by apoptosis. A control protein, consisting of a CD19-specific scFv antibody fragment fused to the ETA-KDEL toxin, failed to induce death of the CD19-negative cell lines U937, HL-60 and THP-1. The CD33-ETA toxin also mediated apoptosis of fresh patient-derived acute myeloid leukaemia cells from bone marrow and peripheral blood. The pronounced ...
Electronic circular dichroism (ECD) of the n-#pi# and #pi# -#pi# transitions of the amide groups in the ultraviolet has become an indispensable tool for qualitative characterization of proteins in solution. Since the existence of such a spectrum (that is, of natural optical activity) comes from the three dimensional interaction of the chromophores in the molecule, CD is exquisitely sensitive to molecular conformation. However, in proteins, the amide transitions available in the near UV are limited in number and are broads and overlapping. Interactions among them yield information about the polymeric backbone, but since such amide electronic excitation are relatively delocalized, the resulting
Experimental investigation data are systematized of free radical states and processes in irradiated proteins. The investigation is performed by the radiospectral methods. Results are discussed in detail of the study of free radicals electronic structure of amino acids, peptides and proteins formed by the action of ionizing radiation. The specificity is stressed of the study of monocrystalls of these compounds by the method of electronic paramagnetic resonance. The nature is also studied of primary centres formed under the effect of radiation on biologically important compounds and their subsequent reactions in solid and liquid solutions. Ion-radical states of different functional groups of the protein molecule are studied. Prospects of the study and the role of anion-radicals in biological processes are discusses.
This paper describes the study of kinetically controlled enzymatic coupling of N- and O-glycopeptide fragments using subtilisin BPN' and two of its variants developed for use in high concentrations of dimethylformamide and in aqueous solution, respectively. Glycosyl amino acids were exploited as the P[sub 1], P[sub 2], P[sub 3], P'[sub 1], P'[sub 2], or P'[sub 3] residue in the enzymatic coupling. Glycosyltransferase-mediated glycosylation of the glycopeptide fragments obtained prior to or after enzymatic peptide bond formation is demonstrated. 19 refs., 5 figs., 1 tab.
Neurodegeneration observed in Alzheimer disease (AD) is believed to be related to the toxicity from reactive oxygen species (ROS) produced in the brain by the amyloid-{beta} (A{beta}) protein bound primarily to copper ions. The evidence for an oxidative stress role of A{beta}-Cu redox chemistry is still incomplete. Details of the copper binding site in A{beta} may be critical to the etiology of AD. Here we present the structure determined by combining x-ray absorption spectroscopy (XAS) and density functional theory analysis of A{beta} peptides complexed with Cu{sup 2+} in solution under a range of buffer conditions. Phosphate-buffered saline buffer salt (NaCl) concentration does not affect the high-affinity copper binding mode but alters the second coordination sphere. The XAS spectra for truncated and full-length A{beta}-Cu{sup 2+} peptides are similar. The novel distorted six-coordinated (3N3O) geometry around copper in the A{beta}-Cu{sup ...
A portion of the active site of rabbit skeletal myosin near the ribose ring of ATP can be labeled by the photoaffinity analogue 3{prime}(2{prime})-O-(4-benzoylbenzoyl)adenosine triphosphate (Bz{sub 2}ATP). The specificity of the photolabeling was assured by first trapping ({sup 14}C)Bz{sub 2}ATP at the active site by use of thiol cross-linking agents. Five radioactive peptides were isolated by high-performance liquid chromatography after extensive trypsin and subtilisin digestion of photolabeled myosin subfragment 1. Four of these peptides were sequenced by Edman techniques, and all originated from a region with the sequence Gly-Glu-Ile-Thr-Val-Pro-Ser-Ile-Asp-Asp-Gln, which corresponds to rabbit myosin heavy chain residues 312-328. The fifth labeled peptide had an amino acid composition appropriate for residues 312-328. Amino acid composition, radiochemical analysis, and sequence data indicate that Ser-324 is the major ...
NMR spectroscopy combined with paramagnetic relaxation agents was used to study the positioning of the 40-residue Alzheimer Amyloid {beta}-peptide A{beta}(1-40) in SDS micelles. 5-Doxyl stearic acid incorporated into the micelle or Mn{sup 2+} ions in the aqueous solvent were used to determine the position of the peptide relative to the micelle geometry. In SDS solvent, the two {alpha}-helices induced in A{beta}(1-40), comprising residues 15-24, and 29-35, respectively, are surrounded by flexible unstructured regions. NMR signals from these unstructured regions are strongly attenuated in the presence of Mn{sup 2+} showing that these regions are positioned mostly outside the micelle. The central helix (residues 15-24) is significantly affected by 5-doxyl stearic acid however somewhat less for residues 16, 20, 22 and 23. This {alpha}-helix therefore resides in the SDS headgroup region with the face with residues 16, 20, 22 and 23 directed away ...
Wound dressings impregnated with silver have a role to play in aiding to reduce both the dressing and wound microbial bioburden. It is therefore imperative that antimicrobial wound dressings have efficacy on a broad range of clinical significant microorganisms. Accordingly, this study aimed to determine the antimicrobial efficacy of a silver alginate dressing against 115 wound isolates that had been isolated routinely from patients at West Virginia University Hospital. Standardised corrected zones of inhibition (CZOIs) were performed on all clinical isolates. It was found that the silver alginate dressing was able to inhibit the growth of all microorganisms tested. In particular, the silver alginate dressing inhibited the growth of Candida albicans and yeasts with CZOI of 3-115 mm. All met...
The effect of phosphonate anion (PHOS) on the corrosion of ordinary steel in simulated cooling water has been studied using weight loss, polarization curves and electrochemical impedance spectroscopy measurements. PHOS was studied in the concentration range from 7.5x10^-^5 to 10^-^3M. The results obtained reveal that PHOS perform excellently as corrosion inhibitor for ordinary steel in simulated cooling water. The inhibition efficiency of PHOS was increased with increasing both its concentration and water circulation velocity. These two factors seem to promote the adsorption of phosphorus and oxygen ions on the metal surface, leading to the formation of a protective layer with a greater charge transfer resistance and lower permeability. The inhibition efficiency decreased slightly with tem...
This research investigated the inhibiting effects that sodium salts of linear monocarboxylic acids displayed towards the corrosion process of AZ31 Mg alloy in ASTM D 1387 saline solution (a synthetic industrial cooling water). The length of the aliphatic chain of the acids ranged between 7 and 15 carbon atoms. The inhibiting action of these salts can be related to the precipitation of an insoluble magnesium salt, which mainly affected the anodic reaction. The aliphatic chain length controlled the anion solubility and the reaction rate of magnesium carboxylate formation. For all the salts, an optimum concentration was experienced: 10{sup -2} M for sodium decanoate (caprate), 10{sup -3} M for sodium dodecanoate (laurate), 10{sup -4} M for sodium tetradecanoate (myristate); when this concentration was exceeded, a diminution (even a disappearance) in the inhibiting action was found. (Abstract Copyright [2009], Wiley ...
Synergism has been observed during inhibiting initiated oxidation of styrene or tetralin by organic phosphites in the presence of complex compounds of some transition metals. The results are given of non-additive intensification of antioxidative activity of triphenylphosphite (TPP) and tri-(4-methyl-6-tert.-- butyl)-phenyl-phosphite (TMBP) in the process of initiated oxidation of styrene or tetralin with addition of acetylacetonates of cobalt and vanadyl. During styrene oxidation, inhibition of the reaction with chelate complex of vanadyl is weakened considerably when phosphite is added into the reaction system. During tetralin oxidation, postcatalytic (or branched) oxidation is observed only for large concentration of vanadyl complex. Addition of TPP to above complex sharply increases the induction period. When the induction period is completed, oxidation of tetralin follows the mechanism of usual, i.e. initiated, reaction.
Green crab (Scylla serrata) alkaline phosphatase (EC 3.1.3.1) is a metalloenzyme, which catalyzes the nonspecific hydrolysis of phosphate monoesters. The kinetics of inhibition of the enzyme by sodium (2, 2'-bipyridine) oxodiperoxovanadate, pV(bipy), has been studied. The time course of the hydrolysis of p-nitrophenyl-phosphate catalyzed by the enzyme in the presence of different pV(bipy) concentrations showed that at each pV(bipy) concentration, the rate decreased with increasing time until a straight line was approached, the straight line slopes are the same for all concentrations. The results suggest that the inhibition of the enzyme by pV(bipy) is a slow, reversible reaction with fractional remaining activity. The microscopic rate constants are determined for the reaction of inhibitor with the enzyme. PMID:10691182
Abstract A Pseudomonas sp. isolate MSB1 efficiently inhibited the growth of Flavobacterium psychrophilum of different serotypes on agar medium. A significant difference in the inhibition was observed between isolates of the less virulent FpT serotype compared to the Fd and Th serotypes. In broth coculture experiments, a low number of cells of MSB1 inhibited and outcompeted the F.psychrophilum cells. Also cell-free culture supernatant of MSB1 clearly repressed the growth of F.psychrophilum. A chromoazurol S assay suggested that MSB1 produced efficient siderophores, which most probably were responsible for the iron deficiency in the supernatant. The limited growth of F.psychrophilum in the supernatant was found to be partly because of the lack of available iron, but the results also indicate...
The obligate biotrophic fungus Golovinomyces orontii causes powdery mildew (PM) disease on its host Arabidopsis thaliana. Most research on the G. orontii?Arabidopsis pathosystem uses rosette leaves as experimental materials, so little is known about the behavior of G. orontii on other Arabidopsis organs. We thus conducted microscopic analyses of the PM infection process on leaves, stems, fruits and roots of Arabidopsis. Adaxial and abaxial surfaces of mature rosette leaves supported G. orontii infection, but growth was somewhat suppressed on cauline leaves. Prepenetration processes (germination and appressorium formation) were strongly inhibited on stems, fruits and roots. To test the effect of alterations in the Arabidopsis cuticle on the inhibition of prepenetration processes on stems, w...
The herbicide atrazine is a known immunotoxicant and an inhibitor of human natural killer (NK) cell lytic function. The precise changes in NK cell lytic function following atrazine exposure have not been fully elucidated. The current study identifies the point at which atrazine exerts its affect on the stepwise process of human NK cell-mediated lyses of the K562 target cell line. Using intracellular staining of human peripheral blood lymphocytes, it was determined that a 24-h in vitro exposure to atrazine did not decrease the level of NK cell lytic proteins granzyme A, granzyme B or perforin. Thus, it was hypothesized that atrazine exposure was inhibiting the ability of the NK cells to bind to the target cell and subsequently inhibit the release of lytic protein from the NK cell. To test t...
Prepulse inhibition (PPI) is a measure of sensorimotor gating, a pre-attentional inhibitory brain mechanism that filters extraneous stimuli. Prepulse inhibition is correlated with measures of cognition and executive functioning, and is considered an endophenotype of schizophrenia and other psychiatric illnesses in which patients show PPI impairments. As a first step toward identifying genes that regulate PPI, we performed a quantitative trait locus (QTL) screen of PPI phenotypes in a panel of mouse chromosome substitution strains (CSSs). We identified five CSSs with altered PPI compared with the host C57BL/6J strain: CSS-4 exhibited decreased PPI, whereas CSS-10, -11, -16 and -Y exhibited higher PPI compared with C57BL/6J. These data indicate that A/J chromosomes 4, 10, 11, 16 and Y harbor...
The acid corrosion inhibition process of mild steel in 1M HCl by 1-butyl-3-methylimidazolium chlorides (BMIC) and 1-butyl-3-methylimidazolium hydrogen sulfate ([BMIM]HSO4) has been investigated using electrochemical impedance, potentiodynamic polarization and weight loss measurements. Potentiodynamic polarization studies indicate the studied inhibitors are mixed type inhibitors. For both inhibitors, the inhibition efficiency increased with increase in the concentration of the inhibitor and the effectiveness of the two inhibitors are in the order [BMIM]HSO4>BMIC. The adsorption of the inhibitors on mild steel surface obeyed the Langmuirs adsorption isotherm. The effect of temperature on the corrosion behavior in the presence of 5x10-3M of inhibitors was studied in the temperature range of 3...
A study of the ordinary mild steel/cooling water interface, with and without inhibitor, was carried out using electrochemical impedance spectroscopy (EIS). EIS spectra in uninhibited medium reveal that a layer of corrosion and scale products is formed naturally and evolves with the immersion time. Monosaccharides derivatives were used as corrosion inhibitors. Most of them exhibit good behaviour against corrosion of ordinary steel in simulated water systems. Their inhibiting efficiency increases with concentration rise and depends on molecular structure especially -OH groups' position on two adjacent carbons and their number. In addition, the effect of MoO4^2^- on the corrosion inhibition in the presence of the best inhibitor was also studied by EIS. The addition of MoO4^2^- enhanced the in...
The effect of TP (triosephosphates:glyceraldehyde-3 phosphate, GAP, +dihydroxyacetone phosphate, DHAP) on respiration, phosphorylation and matrix ATP/ADP ratios of isolated oat mesophyll mitochondria...Full Text Available
Strain F, a recently isolated ruminal bacterium, grew rapidly with glutamate or glutamine as an energy source in the presence but not the absence of Na. Monensin, a Na+/H+ antiporter, completely inhibited...Full Text Available
SummaryIn vivo tumor cell migration through integrin-dependent pathways is key to the metastatic behavior of malignant cells. Using quantitative in vivo...Full Text Available
Peri-prosthetic infections are notoriously difficult to treat as the biomaterial implant is ideal for bacterial adhesion and biofilm formation, resulting in decreased antibiotic sensitivity....Full Text Available
Inhibiting insulin/IGF-1 signalling extends lifespan and delays age-related disease in species throughout the animal kingdom. This life-extension pathway, the first to be defined, was discovered through...Full Text Available
The actions of nicotine, hexamethonium, and ethanol on the hypothalamo-hypophysial system have been investigated in the rat. The antidiuretic action of nicotine was not inhibited by ethanol, nor by...Full Text Available
Stress strongly inhibits proliferation of granule cell precursors in the dentate gyrus, while voluntary running has the opposite effect. Few studies, however, have examined the possible effects...Full Text Available
PurposeDutasteride and finasteride are 5α-reductase inhibitors that dramatically decrease serum levels of dihydrotestosterone. Because androgens...Full Text Available
Epidermal growth factor receptor (EGFR)-specific monoclonal antibodies predominantly inhibit colorectal cancer (CRC) growth by interfering with receptor signaling. Recent analyses have shown that patients...Full Text Available
IgA from normal human serum, a myeloma IgA and human colostral IgA were found to inhibit the IgG-dependent phagocytosis of Candida albicans (CA) blastospores by polymorphonuclear leucocytes...Full Text Available
Sucrose uptake by discs of mature sugar beet root tissue incubated in [14C]-sucrose exhibited nonsaturating kinetics over the concentration range of 1 to 500 millimolar. Uptake was inhibited...Full Text Available
A method is reported which permits selective suppression of absorption of radioactive strontium from ingested food material, permitting the calcium to be available to the body. Studies were carried...Full Text Available
Staphylococcus aureus preferentially catabolizes glucose, generating pyruvate, which is subsequently oxidized to acetate under aerobic growth conditions. Catabolite repression of the...Full Text Available
Since Src kinase inhibitors decrease brain injury produced by intracerebral hemorrhage (ICH) and thrombin is activated following ICH, this study determined whether Src kinase inhibitors decrease...Full Text Available
The concentrations of doxycycline and 4-de-dimethylaminotetracycline required to inhibit 50% of collagenase activity were found to be 15 to 30 microM for human neutrophil and gingival crevicular fluid...Full Text Available
Early on, intriguing biological activities were found associated with the EETs using in vitro systems. Although the EETs other than the 5,6-isomer, are quite stable chemically,...Full Text Available
SummarySoluble epoxide hydrolase (sEH) is a key enzyme in the metabolic conversion and degradation of P450 eicosanoids called epoxyeicosatrienoic acids (EETs). Genetic variations...Full Text Available
BackgroundEsophageal squamous cell carcinoma (ESCC) is one of the most aggressive carcinomas of the gastrointestinal tract. We assessed the relevance of Slug in measuring the invasive...Full Text Available
It has become increasing clear that alterations in cellular metabolism have a key role in the generation and maintenance of cancer. Some of the metabolic changes can be attributed to the activation...Full Text Available
Senescence of Grand Rapids leaf lettuce was greatly reduced at 3 storage temperatures by post-harvest treatment with N,N-dimethylaminosuccinamic acid (Alar) and 2-chloroethyltrimethylammonium chloride...Full Text Available
In vitro translation systems were prepared with supernatant factors from wheat germ and 80S ribosomes from wheat germ, barley embryos, watermelon cotyledons, pea cotyledons, and castor...Full Text Available
Proteins in the ALA-D (delta-aminolaevulinic acid dehydratase) fraction from gel filtration of erythrocyte supernatant (ES) have the highest affinity for lead among erythrocyte constituents in vivo...Full Text Available
The nitrite-reducing activity of the normal susceptible biotype of lambsquarters (Chenopodium album L.) was strongly inhibited by atrazine in the assay medium, both in the case of the...Full Text Available
Although myo-inositol is included in media for the successful growth of plant tissues, the actual requirement of most tissues, including soybean (Glycine max) callus in suspension culture, for myo-inositol...Full Text Available
Target of rapamycin (TOR) kinases control cell growth through two functionally distinct multiprotein complexes. TOR complex 1 (TORC1) controls temporal cell growth and is sensitive to rapamycin, whereas...Full Text Available
The rate and capacity for chloroform (CF) and trichloroethylene (TCE) transformation by a mixed methanotrophic culture of resting cells (no exogenous energy source) and formate-fed cells were measured....Full Text Available
Rapamycin inhibits the mTOR (target of rapamycin) pathway and extends lifespan in multiple species. The tuberous sclerosis complex (TSC) protein is a negative regulator of mTOR. In humans, loss of the...Full Text Available
Platelet-derived growth factor (PDGF) is a potent moderator of soft tissue repair through induction of the inflammatory phase of repair and subsequent enhanced collagen deposition. We examined the effect...Full Text Available
This chapter summarizes research progress in development of phytoremediation technologies. Some soils have become contaminated by trace elements enough to kill plants, inhibit soil organisms, and/or threaten wildlife, humans or the environment. Traditional remediation by dig and haul methods are v...
Inhibition of photosynthesis by ultraviolet-A radiation (UV-A, 315-380 nanometers) was examined in three marine angiosperms: Halophila engelmannii Aschers, Halodule wrightii...Full Text Available
Organophosphates and carbamates (OPs/CMs) are known for their acetylcholinesterase inhibiting character. A cross-sectional study of pesticide handling practices and self-perceived symptoms of acute...Full Text Available
It is generally accepted that hypoxia and recovery from oxygen deprivation contribute to the breakdown and ulceration of human skin. The effects of these stresses on proliferation, differentiation...Full Text Available
Cells of oat coleoptiles (Avena sativa L. cv. “Garry”) have been osmotically shocked in order to observe the effect of alterations of the plasma membrane on some auxin...Full Text Available
Increased oxidative stress is associated with perinatal asphyxia and respiratory distress in the newborn period. Induction of nuclear factor erythroid 2 p45-related factor (Nrf2) has been shown to decrease...Full Text Available
Neutral endopeptidase 24.11 (NEP, CD10) is a cell-surface enzyme expressed by prostatic epithelial cells that cleaves and inactivates neuropeptides implicated in the growth of androgen-independent prostate...Full Text Available
Myelin-associated glycoprotein (MAG) has been implicated in inhibition of nerve regeneration in the CNS. This results from interactions between MAG and the Nogo receptor and gangliosides on...Full Text Available
Flavone and isoflavone phytoestrogens are plant chemicals and are known to be competitive inhibitors of cytochrome P450 aromatase with respect to the androgen substrate. Aromatase is the enzyme that...Full Text Available
RNase BN, the Escherichia coli homolog of RNase Z, was previously shown to act as both a distributive exoribonuclease and an endoribonuclease on model RNA substrates and to be inhibited...Full Text Available
We describe an Ebolavirus minigenome-based system that is suitable for high-throughput screening of compounds able to impair Ebolavirus virus replication and/or transcription....Full Text Available
The present invention relates to a method of acidizing a subterranean formation or well bore employing an acidic solution containing a corrosion inhibitor composition comprising an inhibiting effective amount of an acetylenic alcohol, a quaternary ammonium compound, an aromatic hydrocarbon and an antimony compound.
The exposure of cells to several metal ions stabilizes HIF-1α protein. However, the molecular mechanisms are not completely understood. They may involve inhibition of hydroxylation by either...Full Text Available
Nitric oxide (NO) and related reactive nitrogen species (RNS) play a major role in the pathophysiology of stroke and other neurodegenerative diseases. One of the poorly understood consequences...Full Text Available
1. Nitric oxide generation is important in the regulation of resistance vessel tone. Until now, however, there has been no evidence of such a role for basal generation of nitric oxide in the skin microcirculation...Full Text Available
Sibling Paenibacillus dendritiformis bacterial colonies grown on low-nutrient agar medium mutually inhibit growth through secretion of a lethal factor. Analysis of secretions reveals...Full Text Available
BackgroundLead poisoning affects many organs in the body. Lead inhibits δ-aminolevulinic acid dehydratase (ALAD), an enzyme with two co-dominantly expressed alleles, ALAD1...Full Text Available
Lateral connections in the olfactory bulb were previously thought to be organized for center–surround inhibition. However, recent anatomical and physiological studies showed sparse and distributed...Full Text Available
The agglutination of human platelets by ristocetin and von Willebrand factor was inhibited by aggregated immunoglobulin (Ig)G and by Fc fragments of IgG, but not by Fab, F(ab′)2 or...Full Text Available
Stargardt disease (STGD) is the major form of inherited juvenile macular degeneration. Pyridinium bis-retinoid A2E is a major component of lipofuscin which accumulates in retinal pigment epithelium...Full Text Available
1. The effect of three single doses of nifedipine on exercise-induced asthma has been examined in 11 asthmatic subjects. 2. On four separate days patients undertook 6 min of exercise on a treadmill...Full Text Available
By use of a new computer-assisted u.v.-spectrophotometric assay method, the kinetic parameters of the reaction catalysed by Bacillus licheniformis 749/C beta-lactamase were re-examined and the mode...Full Text Available
BackgroundApproximately 80% of all new HIV-1 infections are acquired through sexual contact. Currently, there is no clinically approved microbicide, indicating a clear and...Full Text Available
Hyperproliferation of the colonic epithelium, leading to expansion of colonic crypt progenitors, is a recognized risk factor for colorectal cancer. Overexpression of progastrin, a nonamidated and incompletely...Full Text Available
The nicotinic acetylcholine receptor (AChR) controls signal transmission between cells in the nervous system. Abused drugs such as cocaine inhibit this receptor. Transient kinetic investigations indicate...Full Text Available
African trypanosomes exert significant morbidity and mortality in man and livestock. Only a few drugs are available for the treatment of trypanosome infections and therefore, the development of new...Full Text Available
Radioactive particles as well as x irradiation from an external source has been used in the treatment of rheumatoid arthritis, osteoarthritis, and ankylosing spondylitis. In order to clarify effects of ionizing irradiation on synovial cells, radioactive gold ("1"9"8Au) and yttrium ("9"0Y) were added to fibroblast cultures derived from human synovial membranes. Other cultures were irradiated by a Picker x-ray machine. Fibroblast growth and hyaluronic acid production were measured. Radioactive gold and yttrium particles induced a significant increase of hyaluronic acid synthesis rate (pg/cell/day) and inhibited fibroblast growth. Fibroblasts continued to overproduce hyaluronic acid and to show growth inhibition 3 weeks after irradiation with radioactive gold. Hydrocortisone inhibited hyaluronic acid overproduction induced by radioactive gold. Overproduction of hyaluronic acid induced by the x-ray machine was ...
SUMMARYDendritic cells (DCs) in mucosal surfaces are early targets for human immunodeficiency virus-1 (HIV-1). DCs mount rapid and robust immune responses upon pathogen encounter....Full Text Available
Deficient wound healing in diabetic patients is very frequent, but the cellular and molecular causes are poorly defined. In this study, we evaluate the hypothesis that high glucose concentrations inhibit...Full Text Available
PurposeThis study was undertaken to determine the neuroprotective effect of granulocyte stimulating factor (G-CSF) on neonatal hypoxic-ischemic brain injury. Materials...Full Text Available
BackgroundBerberine is a plant alkaloid that is widely used as an anti-infective in traditional medicine. Escherichia coli exposed to berberine form filaments, suggesting...Full Text Available
The cancer preventive action of (−)-epigallocatechin gallate (EGCG), found in green tea, is strongly supported by epidemiology and laboratory research data. However, the mechanism by...Full Text Available
Moenomycin A (MmA) belongs to a family of natural products that inhibit peptidoglycan biosynthesis by binding to the peptidoglycan glycosyltransferases (PGTs), the enzymes that make the glycan...Full Text Available
Finasteride, a specific and competitive inhibitor of 5α-reductase enzyme Type 2, inhibits the conversion of testosterone to dihydrotestosterone (DHT). In adults, DHT acts as primary androgen...Full Text Available
Deficits in prepulse inhibition (PPI) are a biological marker for schizophrenia. To unravel the mechanisms that control PPI, we performed quantitative trait loci (QTL) analysis on 1,010 F2 mice derived...Full Text Available
A study has been carried out to investigate whether the action of triclabendazole (TCBZ) against Fasciola hepatica is altered by inhibition of drug metabolism. The cytochrome P450 (CYP 450) enzyme pathway was inhibited using ketoconazole (KTZ) to see whether a TCBZ-resistant isolate could be made more sensitive to TCBZ action. The Oberon TCBZ-resistant and Cullompton TCBZ-susceptible isolates were used for these experiments. The CYP 450 system was inhibited by a 2-h pre-incubation in ketoconazole (40??M), then incubated for a further 22?h in NCTC medium containing either KTZ, KTZ?+?nicotinamide adenine dinucleotide phosphate (NADPH) (1?nM), KTZ?+?NADPH?+?TCBZ (15??g/ml), or KTZ?+?NADPH?+?triclabendazole sulphoxide (TCBZ.SO; 15??g/ml). Changes to fluke ultrastructure following drug treatmen...
AIM: To analyze the antiviral mechanism of Epigallocatechin gallate (EGCG) against hepatitis B virus (HBV) replication.METHODS: In this research, the HBV-replicating cell line HepG2.117 was used...Full Text Available
Trypanothione reductase (TryR) is a key enzyme involved in the oxidative stress management of the Trypanosoma and Leishmania parasites, which helps to maintain an intracellular reducing environment...Full Text Available
Based on in vitro rat and human hepatocyte uptake studies showing inhibition of warfarin uptake in the presence of the non-specific organic anion transporting polypeptide (OATP)...Full Text Available
Drugs used for the inhibition of DNA viruses, such as iododeoxyuridine, adenine arabinoside, or trifluorothymidine, are not biochemically selective in their action and also interfere with normal cellular...Full Text Available
The hypothesis that the antiarrhythmic drug amiodarone slows down the heart rate by its inhibitory action on the intracellular conversion of thyroxine (T4) to 3,5,3' triiodothyronine (T3) was investigated....Full Text Available
Genome endoreduplication during mammalian development is a rare event for which the mechanism is unknown. It first appears when fibroblast growth factor 4 (FGF4) deprivation induces differentiation...Full Text Available
Experiments were performed to investigate the involvement of the cell membrane in the excision DNA repair process in Escherichia coli. Two membrane-binding drugs, procaine and phenethyl alcohol (PEA), inhibited liquid-holding recovery (LBR) in u.v.-irradiated E. coli wild-type and recA strains. In uvrB and polA strains where, after u.v.-irradiation, LHR was absent the two drugs had no effect. Both drugs markedly reduced the removal of u.v.-induced thymine dimers in the DNA of wild-type cells (H/r30). Analysis by alkaline sucrose gradients revealed that PEA inhibited the incision step in excision repair. In contrast, procaine had no effect on incision but apparently inhibited the late steps in excision repair. PEA dissociated DNA from the cell membrane, whereas procaine did not. The results suggest that the two drugs PEA and procaine inhibit LHR and the excision repair process operating on u.v.-induced ...
Cytosolic ATP-phosphofructokinase (PFK) from spinach leaves (Spinacia oleracea L.) was inhibited by submillimolar concentrations of free Mg2+. The free Mg2+ concentration...Full Text Available
Cryptococcus neoformans is a ubiquitously distributed human pathogen. It is also a model system for studying fungal virulence, physiology and differentiation. Light is known to inhibit...Full Text Available
The acid corrosion inhibition process of mild steel in 1 M HCl by 1-butyl-3-methylimidazolium chlorides (BMIC) and 1-butyl-3-methylimidazolium hydrogen sulfate ([BMIM]HSO{sub 4}) has been investigated using electrochemical impedance, potentiodynamic polarization and weight loss measurements. Potentiodynamic polarization studies indicate the studied inhibitors are mixed type inhibitors. For both inhibitors, the inhibition efficiency increased with increase in the concentration of the inhibitor and the effectiveness of the two inhibitors are in the order [BMIM]HSO{sub 4} > BMIC. The adsorption of the inhibitors on mild steel surface obeyed the Langmuir's adsorption isotherm. The effect of temperature on the corrosion behavior in the presence of 5 x 10{sup -3} M of inhibitors was studied in the temperature range of 303-333 K. The associated activation energy of corrosion and other thermodynamic parameters such as enthalpy of ...
The acid corrosion inhibition process of mild steel in 1 M HCl by 1-butyl-3-methylimidazolium chlorides (BMIC) and 1-butyl-3-methylimidazolium hydrogen sulfate ([BMIM]HSO_4) has been investigated using electrochemical impedance, potentiodynamic polarization and weight loss measurements. Potentiodynamic polarization studies indicate the studied inhibitors are mixed type inhibitors. For both inhibitors, the inhibition efficiency increased with increase in the concentration of the inhibitor and the effectiveness of the two inhibitors are in the order [BMIM]HSO_4 > BMIC. The adsorption of the inhibitors on mild steel surface obeyed the Langmuir's adsorption isotherm. The effect of temperature on the corrosion behavior in the presence of 5 x 10"-"3 M of inhibitors was studied in the temperature range of 303-333 K. The associated activation energy of corrosion and other thermodynamic parameters such as enthalpy of activation (#DELTA#H), entropy of ...
The incorporation of [14C]phenylalanine and [1,6-14C]shikimic acid into tyrosine was investigated in the callus of Portulaca grandiflora, var. JR (L.). By inhibiting...Full Text Available
Psychopathic individuals are generally unresponsive to motivational and emotional cues that facilitate behavioral regulation. A putative mechanism for this deficiency is Gray’s (1971)...Full Text Available
2-Isopropyl-4-dimethylamino-5-methylphenyl-1-piperidine carboxylate methyl chloride (AMO-1618) inhibits the activity of a cholinesterase isolated from mung bean (Phaseolus aureus) roots...Full Text Available
We introduce cyclophosphamide-induced alopecia (CYP-IA) in C57BL-6 mice as a clinically relevant model for studying the biology of chemotherapy-induced alopecia and for developing anti-alopecia drugs....Full Text Available
Terfestatin A (TrfA), terphenyl-β-glucoside, was isolated from Streptomyces sp. F40 in a forward screen for compounds that inhibit the expression of auxin-inducible...Full Text Available
Cells have an internal compass that enables them to move along shallow chemical gradients. As amoeboid cells migrate, signaling events such as Ras and PI3K activation occur spontaneously on pseudopodia....Full Text Available
Store-operated Ca2+ entry (SOCE) is a ubiquitous Ca2+ influx pathway involved in control of multiple cellular and physiological processes including cell proliferation. Recent evidence...Full Text Available
Rationale: Ventilator-induced lung injury (VILI) leads to an unacceptably high mortality. In this regard, the antiinflammatory properties of inhaled carbon monoxide (CO) may provide...Full Text Available
Studies on alcoholic liver injury mechanisms show a significant inhibition of the proteasome activity. To investigate this phenomenon, we isolated proteasome complexes from the liver of rats...Full Text Available
BackgroundCancer stem cells (CSCs) have increased resistance to cancer chemotherapy. They can be enriched as drug-surviving CSCs (D-CSCs) by growth with chemotherapeutic drugs, and/or...Full Text Available
BackgroundCardiovascular disease (CVD) is a leading cause of mortality in the United States as well as globally. Epidemiological studies show that regular fruit and vegetable consumption...Full Text Available
Nitric oxide (NO)-based therapies effectively inhibit neointimal hyperplasia in animal models of arterial injury and bypass grafting, but are not available clinically. We created a simple, effective,...Full Text Available
Many auxin responses are dependent on redistribution and/or polar transport of indoleacetic acid. Polar transport of auxin can be inhibited through the application of phytotropins such as 1-naphthylphthalamic...Full Text Available
Lovatt et al. (1979 Plant Physiol 64: 562-569) have previously demonstrated that end-product inhibition functions as a mechanism regulating the activity of the orotic acid pathway in...Full Text Available
BackgroundMutations of the amyloid precursor protein gene (APP) are found in familial forms of Alzheimer's disease (AD) and some lead to the elevated production...Full Text Available
Cyclothiazomycin B1 (CTB1) is an antifungal cyclic thiopeptide isolated from the culture broth of Streptomyces sp. HA 125-40. CTB1 inhibited the growth of several filamentous fungi including plant pathogens along with swelling of hyphae and spores. The antifungal activity of CTB1 was weakened by hyperosmotic conditions, and hyphae treated with CTB1 burst under hypoosmotic conditions, indicating increased cell wall fragility. CTB1-sensitive fungal species contain high levels of cell wall chitin and/or chitosan. Unlike nikkomycin Z, a competitive inhibitor of chitin synthase (CHS), CTB1 did not inhibit CHS activity. Although CTB1 inhibited CHS biosynthesis, the same result was also obtained with a non-specific proteins inhibitor, cycloheximide, which did not reduce cell wall rigidity. These ...
Background and purpose:Glycyrrhizae radix has been widely used as a cytoprotective, plant-derived medicine. We have identified a flavanoid, liquiritigenin, as an...Full Text Available
Among the several rotenoids, amorphigenin is isolated from the leaves of Amopha Fruticosa and it is known that has anti-proliferative effects and anti-cnacer effects in many cell types....Full Text Available
Albendazole binds to parasite's tubulin inhibiting its glucose absorption. Its common adverse effects are nausea, vomiting, constipation, thirst, dizziness, headache, hair loss and pruritus. Although...Full Text Available
Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors belonging to the nuclear hormone receptor superfamily. Their discovery in the 1990s provided insights...Full Text Available
BackgroundObesity is one of the principal causative factors involved in the development of metabolic syndrome. AMP-activated protein kinase (AMPK) is an energy sensor that regulates...Full Text Available
Plumbagin is found in many herbal plants and inhibits the growth of various bacteria. Escherichia coli strains are relatively resistant to this drug. The mechanism of resistance is...Full Text Available
BackgroundCompared to outbred Sprague Dawley (SD) rats, inbred Brown Norway (BN) rats exhibit less prepulse inhibition of startle (PPI) at long prepulse intervals,...Full Text Available
The initiation and inhibition of pitting corrosion on zirconium and hafnium in aqueous solutions have been investigated by potentiodynamic, potentiostatic and galvanostatic measurements at 25/sup 0/C. Effects of Cl/sup -/, Br/sup -/and I/sup -/ have been examined over a range of salt concentrations and pH. All three halide ions cause pitting attack on the two metals, but this may be inhibited by other anions. The results show that hafnium is more easily protected against pitting than is zirconium. The data are treated by the Butler-Volmer equation to yield more information about the mechanisms of the pitting corrosion.
The analgesic, dipyrone (1,phenyl-2,3-dimethyl-5-pyrazolone-4-methylamino methane sulphonate sodium), at 20 mM concentration, inhibited the rejoining of single-strand scissions in DNA of Escherichia coli B/r cells induced by 20 krad gamma-radiation. The chemical altered the cell membrane structure as evidenced from the uptake of acriflavin, the efflux of potassium ions from the bacterial cells and the inhibition of alkaline phosphatase-a cell membrane associated enzyme. (author). 18 refs., 6 figures.
The analgesic, dipyrone (1,phenyl-2,3-dimethyl-5-pyrazolone-4-methylamino methane sulphonate sodium), at 20 mM concentration, inhibited the rejoining of single-strand scissions in DNA of Escherichia coli B/r cells induced by 20 krad gamma-radiation. The chemical altered the cell membrane structure as evidenced from the uptake of acriflavin, the efflux of potassium ions from the bacterial cells and the inhibition of alkaline phosphatase-a cell membrane associated enzyme. (author).
Aldosterone has been suggested to elicit vessel contraction via a nongenomic mechanism. We tested this proposal in microdissected, perfused rabbit renal afferent arterioles. Aldosterone had no effect on internal diameter in concentrations from 10(-10) to 10(-5) mol/L, but aldosterone abolished the ability of 100 mmol/L KCl to induce vascular contraction. The inhibitory effect of aldosterone was observed from 1 pmol/L. The inhibitory effect was significant after 5 minutes and maximal after 20 minutes and was fully reversible. Actinomycin D (10(-6) mol/L) prolonged the effect of aldosterone. The effect was abolished by the mineralocorticoid receptor antagonist spironolactone (10(-7) mol/L) but not by the glucocorticoid receptor antagonist mifepristone (10(-6) mol/L). The K+-mediated increase of intracellular calcium concentration in afferent arterioles was not affected by aldosterone. Mineralocorticoid receptor was detected by reverse transcription-polymerase chain reaction and ...
Spike-timing-dependent plasticity (STDP), a form of Hebbian plasticity, is inherently stabilizing. Whether and how GABAergic inhibition influences STDP is not well understood. Using a model neuron driven by converging inputs modifiable by STDP, we determined that a sufficient level of inhibition was critical to ensure that temporal coherence (correlation among presynaptic spike times) of synaptic inputs, rather than initial strength or number of inputs within a pathway, controlled postsynaptic spike timing. Inhibition exerted this effect by preferentially reducing synaptic efficacy, the ability of inputs to evoke postsynaptic action potentials, of the less coherent inputs. In visual cortical slices, inhibition potently reduced synaptic efficacy at ages during but not before the critical period of ocular dominance (OD) plasticity. Whole-cell recordings revealed that the amplitude of unitary IPSCs from ...
The effects of purified Helminthosporium maydis T (HmT) toxin on active Ca/sup 2 +/ transport into isolated mitochondria and microsomal vesicles were compared for a susceptible (T) and a resistant (N) strain of corn (Zea mays). ATP, malate, NADH, or succinate could drive /sup 45/Ca/sup 2 +/ transport into mitochondria of corn roots. Ca/sup 2 +/ uptake was dependent on the proton electrochemical gradient generated by the redox substrates or the reversible ATP synthetase, as oligomycin inhibited ATP-driven CA/sup 2 +/ uptake while KCN inhibited transport driven by the redox substrates. Purified native HmT toxin completely inhibited Ca/sup 2 +/ transport into T mitochondria at 5 to 10 nanograms per milliliter while transport into N mitochondria was decreased slightly by 100 nanograms per milliliter toxin. Malate-driven Ca/sup 2 +/ transport in T mitochondria was frequently more inhibited by 5 nanograms per ...
Amyloid precursor protein (APP), a key protein in pathogenesis of Alzheimer's disease (AD), is a type I transmembrane protein which can be cleaved by b- and g-secretase to release the amyloidogenic b-amyloid peptides (Ab) and the APP intracellular domain (AICD). While Ab has been widely believed to initiate pathogenic cascades culminating AD, the physiological functions and regulations of AICD remain elusive. In present study, endogenous AICD was demonstrated to be increased by canonical Wnt signal. Instead of due to g-secretase activity, enhanced AICD expression was found due to the increased protein stability by Wnt/b-catenin. b-Catenin was demonstrated to be an associating partner of AICD, capable of promoting AICD mediated transcriptional activity. Investigation by AICD mutants proved ...
A bioartificial kidney, which is composed of a membrane cartridge with renal epithelial cells, can substitute important kidney functions in patients with renal failure. A particular challenge is the maintenance of monolayer integrity and specialized renal epithelial cell functions ex vivo. We hypothesized that this can be improved by electro-spun, supramolecular polymer membranes which show clear benefits in ease of processability. We found that after 7?d, in comparison to conventional microporous membranes, renal tubular cells cultured on top of our fibrous supramolecular membranes formed polarized monolayers, which is prerequisite for a well-functioning bioartificial kidney. In future, these supramolecular membranes allow for incorporation of peptides that may increase cell function even further. PMID:20715132
Abstract Acid-treated cobia (Rachycentron canadum) skin was extracted in a retort (121C) to obtain retorted skin gelatin hydrolysates (RSGHs) containing antioxidant peptides with noticeable antioxidant properties. To improve the antioxidant activity of cobia RSGHs, five processing factors including alkali concentration, alkali pretreatment time, phosphoric acid concentration (PC), water/skin ratio (WS) and retorting time (RT) in RSGH production were screened using a fractional factorial design to identify critical factors. It indicated that PC, WS and RT had significant effects on ,-diphenyl--picrylhydrazyl (DPPH) scavenging by RSGHs. Subsequently, the optimization of PC, WS and RT on the DPPH scavenging of RSGHs was studied using a central composite design to collect data that resulted in...
The T cell receptor is a fundamental mediator of the adaptive immune responses, since TR ab on T cells recognize foreign structures (peptides derived from processed antigens) bound to the major histocompatibility complex (MHC) on APC cells. In the present study, we report the cloning of six TRB chains cDNA sequences from gilthead sea bream (Sparus aurata), a fish of high economical impact in South Mediterranean aquaculture. The V-BETA domains have the canonical features of known teleost and mammalian TR V-BETA domains and have been divided in four different subgroups. A multiple alignment of the six sea bream TRB chains with other known TRB sequences was assembled and showed the conservation of the four cysteine residues involved in disulphide bonds and of some amino acids with an importan...
Endogenous opioid peptides (EOP) are molecules affecting many biological functions influencing productive and reproductive performance. They increase in stress conditions and interact with specific opioidergic receptors (OR): delta, kappa and mu. Several studies in other animal species suggest that they can also affect sperm cell motility. In fish the ionic external environment modulates the increase of intracellular calcium ion that is required to activate sperm motility after spawning. In mammals OR are functionally associated to calcium channels and in fishes calcium is highly required for fish sperm activation. In this study the presence of OR on spermatozoa of two Perciform fish, the sharpsnout seabream (Diplodus puntazzo, family Sparidae) and the European sea bass (Dicentrarchus labr...
Abstract Many solute carrier transporters that interact with anticancer agents and contribute to their pharmacokinetics have been shown to be differentially upregulated in cancer cells as a result of adaptive response to altered nutritional requirements. This review focuses on pathophysiological function of membrane transporters responsible for the influx of physiological substances including oligopeptides, amino acids, and organic cations and anions, and summarizes the recent knowledge regarding mechanisms in their gene expressions. Broad substrate specificity of enhanced oligopeptide H+/peptide cotransporter 1 activity in cancer cells is useful for tumor tissue-specific delivery of chemotherapeutic agents and positron emission tomography diagnostic probes. Amino acid transporters such as...
Plasmid pRK404-a smaller derivative of RK2-is a tetracycline-resistant broad-host-range vector that carries a multiple cloning site and the lacZ(alpha) peptide that enables blue/white selection for cloned inserts in Escherichia coli. We present herein the complete and annotated sequence of pRK404 and three related vectors-pRK437, pRK442, and pRK442(H). These derivatives have proven to be valuable tools for genetic manipulation in Gram-negative bacteria. The knowledge of their complete sequences will facilitate efficient future engineering of them and will enhance their general applicability to the design of genetic systems for use in organisms for which new genomic sequence data are becoming available.
Aberrant amyloid-b peptide (Ab) accumulation along with altered expression and function of nicotinic acetylcholine receptors (nAChRs) stand prominently in the etiology of Alzheimer's disease (AD). Since the discovery that Ab is bound to a7 nAChRs under many experimental settings, including post-mortem AD brain, much effort has been expended to understand the implications of this interaction in the disease milieu. This research update will review the current literature on the a7 nAChR-Ab interaction in vitro and in vivo, the functional consequences of this interaction from sub-cellular to cognitive levels, and discuss the implications these relationships might have for AD therapies.
Abstract Under eons of evolutionary and environmental pressure, biological systems have developed strong and lightweight peptide-based polymeric materials by using the 20 naturally occurring amino acids as principal monomeric units. These materials outperform their man-made counterparts in the following ways: 1)-multifunctionality/tunability, 2)-adaptability/stimuli-responsiveness, 3)-synthesis and processing under ambient and aqueous conditions, and 4)-recyclability and biodegradability. The universal design strategy that affords these advanced properties involves -bottom-up- synthesis and modular, hierarchical organization both within and across multiple length-scales. The field of -biomimicry--elucidating and co-opting nature-s basic material design principles and molecular building blo...
Many existing agents for diabetes therapy are unable to restore or maintain normal glucose homeostasis or prevent the eventual emergence of hyperglycemia-related complication. Therefore, agents based on novel mechanisms are sought to complement and extend the current therapeutic approaches. Based on the initial paper research, we focused on active STAT3 as an attractive pharmacological target for type 2 diabetes. The subsequent text mining with a unique query to identify suppressors but not activators of STAT3 revealed the ERK2/STAT3 pathway as a novel diabetes target. The description of ERK2 inhibitors as diabetes target had not been found in our text mining research at present. The mechanism-based peptide inhibitor for ERK2 was identified using the knowledge of the KIM sequence, which ha...
Background: Thyroid-stimulating autoantibodies (TSAb) bind to the thyrotropin receptor (TSHR) extracellular domain, or ectodomain (ECD), comprising a leucine-rich repeat domain (LRD) linked by a hinge region to the transmembrane domain (TMD). The LRD (residues 22???260; signal peptide 1???21) contains two disulfide-bonded loops at its N-terminus. In the crystal structure of the isolated LRD complexed with human TSAb monoclonal antibody (mAb) M22, N-terminal disulfide loop 1 (residues 22???30) could not be determined because of crystal disorder. Nevertheless, present crystal structure data are interpreted to exclude a role for the LRD N-terminal disulfide loops in the TSAb epitope(s), contradicting prior functional evidence of a role for these loops in TSAb function. Materials and Methods: ...
The authors have cloned and determined the entire nucleotide sequence of cDNAs corresponding to the putative {alpha} subunits of the human and rat mast cell high-affinity IgE receptors. Both human and rat cDNAs encode an NH{sub 2}-terminal signal peptide, two immunoglobulin-like extracellular domains (encoded by discrete exons), a hydrophobic transmembrane region, and a positively charged cytoplasmic tail. The human and rat {alpha} subunits share an overall homology with one another and the immunoglobulin gene family, suggesting that they arose from a common ancestral gene and continue to share structural homology with their ligands. In addition, the rat gene is transcribed into at least three distinct forms, each of which yields a somewhat different coding sequence.
Successful electron capture dissociation (ECD) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) applications to peptide and protein structural analysis have been enabled by constant progress in implementation of improved electron injection techniques. The rate of ECD product ion formation has been increased to match the liquid chromatography and capillary electrophoresis timescales, and ECD has been combined with infrared multiphoton dissociation in a single experimental configuration to provide simultaneous irradiation, fast switching between the two techniques, and good spatial overlap between ion, photon, and electron beams. Here we begin by describing advantages and disadvantages of the various existing electron injection techniques for ECD in FT-ICR MS. We next ...
Summation Copper-64 (T1/2?=?12.7 hours; ?+, 0.653?MeV [17.8 %]; ??, 0.579?MeV [38.4 %]) has decay characteristics that allow for positron emission tomography (PET) imaging and targeted radiotherapy of cancer. The well-established coordination chemistry of copper allows for its reaction with a wide variety of chelator systems that can potentially be linked to peptides and other biologically relevant small molecules, antibodies, proteins, and nanoparticles. The 12.7-hours half-life of 64Cu provides the flexibility to image both smaller molecules and larger, slower clearing proteins and nanoparticles. In a practical sense, the radionuclide or the 64Cu-radiopharmaceuticals can be easily shipped for PET imaging studies at sites remote to the production facility. Due to the versatility of 64Cu, ...
Phage display is effective in screening peptides that mimic venom's neutralizing epitopes. A phage display cyclized heptapeptide library (C7C library) was panned with purified divalent antivenin IgG, which neutralizes Naja naja atra venom (NAV) and Bungarus multicinctus venom (BMV). The selected heptapeptide sequences were aligned with known protein sequences of NAV and BMV in GenBank. One of the four consensus sequences, L/PKSSLL, mimicked the crucial epitope on Loop III of Taiwan cobra cardiotoxin that is associated with the venom's lethal potency. In dot blot analysis, several clones showed varying reactivities for NAV monovalent antivenin and lesser cross-reactions with BMV monovalent antivenin. The KSSLLRN-carrying phage occurred four times in selected clones and showed the strongest ...
Gastrointestinal patches represent a novel multiparticulate drug delivery system able to increase the intestinal absorption of drugs with poor bioavailability. The number of patches to administer is a critical issue since it is related to the surface and drug concentration at the absorption site. The objective of this article is to evaluate the effect of the number of administered patches on the final absorption of leuprolide, a peptide chosen as model drug, assuming complete adhesion of all the devices to the intestinal membrane. The same dose of leuprolide was encapsulated into 2, 4 and 6 patches; the resulting intestinal absorption profiles were measured with the Ussing chamber ex vivo experimental setup and compared between them. The results showed that varying the number of patches, t...
Abstract A 3-month, open-label, single-center study was conducted to determine whether a uniquely formulated and physiologically balanced topical treatment serum containing multiple growth factors, cytokines, peptides, antioxidants and depigmenting agents could improve the visible signs of facial photodamage. Thirty-seven females, aged 32-55 years, with mild to severe, fine and coarse peri-ocular wrinkles were enrolled and completed the study. Subjects applied the treatment serum to the face twice daily for 3 months in conjunction with a basic skincare regimen. Clinical evaluations of photodamage were performed at baseline and months 1, 2 and 3. Cutometer measurements and subject self-assessment questionnaires were also conducted during the study. Clinical evaluations showed statistically ...
Transgenic plants offer advantages for biomolecule production because plants can be grown on a large scale and the recombinant macromolecules can be easily harvested and extracted. We introduced an Aspergillus phytase gene into canola (Brassica napus) (line 9412 with low erucic acid and low glucosinolates) by Agrobacterium-mediated transformation. Phytase expression in transgenic plant was enhanced with a synthetic phytase gene according to the Brassica codon usage and an endoplasmic reticulum (ER) retention signal KDEL that confers an ER accumulation of the recombinant phytase. Secretion of the phytase to the extracellular fluid was also established by the use of the tobacco PR-S signal peptide. Phytase accumulation in mature seed accounted for 2.6% of the total soluble proteins. The enzy...
Protein hydrogels were prepared by substituting ovalbumin with different concentrations of ethyl vinyl sulfone (EVS) or acrylic acid (AA) and crosslinking with divinyl sulfone (DVS). Fourier transform-infrared (FT-IR) spectroscopic studies confirmed the addition of EVS, AA, and DVS onto the protein. Swelling was assessed as a function of pH in the range of 2.5 to 9.4 and ionic strength. The elastic modulus of the gels was determined in shear and compression. Stress relaxation was assessed in compression. The substituent highly affected swelling and modulus with both hydrogels displaying non-Gaussian behavior in the range of hydrogel environments studied. Acrylic acid substituted ovalbumin exhibited a decreasing modulus with increasing swelling behaving as a polyelectrolyte with low added s...
Carbohydrate and nucleotide structural determination using modern spectroscopic techniques is dependent on our ability to label oligonucleotides and oligosaccharides with stable isotopes. Uniform Carbon 13 and Nitrogen 15 labeling of oligonucleotides is important to present-day efforts, which are focused on determining the structure of relatively small oligosaccharides and oligonucleotides, which form the elements of larger structures. Because of the relatively recent interest in three-dimensional structure, the development of techniques used to label them has lagged behind parallel techniques used to label peptides and proteins. Therefore, this group`s discussion focused primarily on problems faced today in obtaining oligonucleotides labeled uniformly with carbon 13 and nitrogen 15.
Using the peptide hormone glucagon and Ab(1-40) as model systems, we have sought to elucidate the mechanisms by which fibrils grow and multiply. We here present real-time observations of growing fibrils at a single-fibril level. Growing from preformed seeds, glucagon fibrils were able to generate new fibril ends by continuously branching into new fibrils. To our knowledge, this is the first time amyloid fibril branching has been observed in real-time. Glucagon fibrils formed by branching always grew in the forward direction of the parent fibril with a preferred angle of 35-40degree. Furthermore, branching never occurred at the tip of the parent fibril. In contrast, in a previous study by some of us, Ab(1-40) fibrils grew exclusively by elongation of preformed seeds. Fibrillation kinetics i...
Banana bunchy top virus (BBTV), family Nanaviridae, genus Babuvirus, is a single stranded DNA virus (ssDNA) that causes banana bunchy top disease (BBTD) in banana plants. It is the most common and most destructive of all viruses in these plants and is widespread throughout the Asia-Pacific region. In this study we isolated, cloned and sequenced a BBTV sample from Hainan Island, China. The results from sequencing and bioinformatics analysis indicate this isolate represents a satellite DNA component with 12 DNA sequences motifs. We also predicted the physical and chemical properties, structure, signal peptide, phosphorylation, secondary structure, tertiary structure and functional domains of its encoding protein, and compare them with the corresponding quantities in the replication initiatio...
Calcium-activated chloride channels (CaCCs) are widely expressed in mammalian tissues, including intestinal epithelia, where they facilitate fluid secretion. Potent, selective CaCC inhibitors have not been available. We established a high-throughput screen for identification of inhibitors of a human intestinal CaCC based on inhibition of ATP/carbachol-stimulated iodide influx in HT-29 cells after lentiviral infection with the yellow fluorescent halide-sensing protein YFP-H148Q/I152L. Screening of 50,000 diverse, drug-like compounds yielded six classes of putative CaCC inhibitors, two of which, 3-acyl-2-aminothiophenes and 5-aryl-2-aminothiazoles, inhibited by >95% iodide influx in HT-29 cells in response to multiple calcium-elevating agonists, including thapsigargin, without inhibition of calcium elevation, calcium-calmodulin kinase II activation, or cystic fibrosis transmembrane conductance regulator chloride channels. ...
PNAS-4, a novel pro-apoptotic gene activated during the early response to DNA damage, can inhibit proliferation via apoptosis when overexpressed in some tumor cells. Recent studies have indicated that honokiol can induce apoptosis, inhibit angiogenesis, and suppress tumor growth. In the present study, we investigated whether mouse PNAS-4 (mPNAS-4) could augment the apoptosis of tumor cells induced by honokiol in vitro, and whether the antiangiogenic activity of honokiol and induction of apoptosis by mPNAS-4 could work cooperatively to improve the antitumor efficacy in vivo. In vitro, mPNAS-4 inhibited proliferation of murine colorectal carcinoma CT26 and Lewis lung carcinoma LL2 cells through induction of apoptosis, and significantly augmented the apoptosis of CT26 and LL2 cells induced by honokiol. Compared with treatment with mPNAS-4 or honokiol alone, in vivo systemic administration of an expression plasmid encoding ...
S100A4, a member of the Ca(2+)-activated S100 protein family, regulates the motility and invasiveness of cancer cells. Moreover, high S100A4 expression levels correlate with poor patient survival in several cancers. Although biochemical, biophysical, and structural data indicate that S100A4 is a noncovalent dimer, it is unknown if two functional S100A4 monomers are required for the productive recognition of protein targets and the promotion of cell invasion. To address this question, we created covalently linked S100A4 dimers using a glycine rich flexible linker. The single-chain S100A4 (sc-S100A4) proteins exhibited wild-type affinities for calcium and nonmuscle myosin-IIA, retained the ability to regulate nonmuscle myosin-IIA assembly, and promoted tumor cell invasion when expressed in S100A4-deficient colon carcinoma cells. Mutation of the two calcium-binding EF-hands in one monomer, while leaving the other monomer intact, caused a 30-60-fold reduction in binding affinity for ...
Purpose: Photodynamic therapy (PDT) is based on the interaction of a photosensitizing (PS) agent, light, and oxygen. Few new PS agents are being developed to the in vivo stage, partly because of the difficulty in finding the right treatment conditions. Response surface methodology, an empirical modeling approach based on data resulting from a set of designed experiments, was suggested as a rational solution with which to select in vivo PDT conditions by using a new peptide-conjugated PS targeting agent, neuropilin-1. Methods and Materials: A Doehlert experimental design was selected to model effects and interactions of the PS dose, fluence, and fluence rate on the growth of U87 human malignant glioma cell xenografts in nude mice, using a fixed drug-light interval. All experimental results were computed by Nemrod-W software and Matlab. Results: Intrinsic diameter growth rate, a tumor growth parameter independent of the initial volume of the tumor, was selected as ...
PACAP (pituitary adenylate cyclase activating polypeptide) is widely distributed neuropeptide acting via three subtypes of receptors, PAC(1), VPAC(1) and VPAC(2). Here we examined the localisation and nature of PACAP-immunoreactive nerves in the rat thyroid and parathyroid glands and defined the distribution of PAC(1), VPAC(1) and VPAC(2) receptor mRNA's. In the parathyroid gland a large number of nerve fibres displaying PACAP-immunoreactivity were distributed beneath the capsule, around blood vessels and close to glandular cells. Most of the PACAP-nerves were sensory, since they co-stored CGRP (calcitonin-gene-related peptide) and were sensitive to capsaicin-treatment. mRNA's for PAC(1) and VPAC(2) receptors occurred in the parathyroid gland, mainly located in the glandular cells. In the thyroid gland PACAP-immunoreactive nerve fibres were associated with blood vessels, thyroid follicles and parafollicular C-cells. A high degree of co-existence between PACAP and ...
When Silk fibre derived from Bombyx mori, a native biopolymer, was dissolved in highly concentrated neutral salts such as CaCl{sub 2}, the regenerated liquid silk, a gradually degraded peptide mixture of silk fibroin, could be obtained. The silk fibroin nanoparticles were prepared rapidly from the liquid silk by using water-miscible protonic and polar aprotonic organic solvents. The nanoparticles are insoluble but well dispersed and stable in aqueous solution and are globular particles with a range of 35-125 nm in diameter by means of TEM, SEM, AFM and laser sizer. Over one half of the {epsilon}-amino groups exist around the protein nanoparticles by using a trinitrobenzenesulfonic acid (TNBS) method. Raman spectra shows the tyrosine residues on the surface of the globules are more exposed than those on native silk fibers. The crystalline polymorph and conformation transition of the silk nanoparticles from random-coil and {alpha}-helix form (Silk I) into ...
Autoreactive cytotoxic CD8 T-cells (CTLs) play a key pathogenic role in the destruction of insulin-producing beta-cells resulting in type 1 diabetes. However, knowledge regarding their targets is limited, restricting the ability to monitor the course of the disease and immune interventions. In a multi-step discovery process to identify novel CTL epitopes in human preproinsulin (PPI), PPI was digested with purified human proteasomes, and resulting COOH-fragments aligned with algorithm-predicted HLA-binding peptides to yield nine potential HLA-A1, -A2, -A3 or -B7-restricted candidates. An UV-exchange method allowed the generation of a repertoire of multimers including low-affinity HLA-binding peptides. These were labeled with quantum dot-fluorochromes and encoded in a combinatorial fashion, allowing parallel and sensitive detection of specific, low-avidity T-cells. Significantly increased frequencies of T-cells against four novel PPI epitopes ...
The active site of chicken gizzard myosin was labeled by direct photoaffinity labeling with ["3H]UDP. ["3H] UDP was stably trapped at the active site by addition of vanadate (Vi) and Co"2"+. The extraordinary stability of the myosin.Co2+.[3H]UDP.Vi complex (t1/2 greater than 5 days at 0 degrees C) allowed it to be purified free of extraneous ["3H]UDP before irradiation began. Upon UV irradiation, greater than 60% of the trapped ["3H]UDP was photoincorporated into the active site. Only the 200-kDa heavy chain was labeled, confirming earlier results using ["3H]UTP. Extensive tryptic digestion of photolabeled myosin subfragment 1 followed by high performance liquid chromatography separations and removal of nucleotide phosphates by treatment with alkaline phosphatase allowed two labeled peptides to be isolated. Sequencing of the labeled peptides and radioactive counting showed that Glu185 was the residue labeled. Since UDP is a zero-length ...
Germination inhibition of the marine macrophyte Phyllospora comosa was utilized as a sub-lethal end-point to assess and compare the effects of four oil dispersants and dispersed diesel fuel and crude oil combinations. Inhibition of germination by the water-soluble fraction of diesel fuel increased following the addition of each of the dispersants; the nominal 48-h EC{sub 50} concentration of diesel fuel declined from 6800 to approximately 400 {mu}l 1{sup -1} nominal for each dispersed combination. This contrasted with crude oil, where the addition of two dispersants resulted in an enhanced germination rate and an increase in nominal EC{sub 50} concentrations from 130 {mu}l 1{sup -1} for the undispersed crude to 4000 and 2500 {mu}l 1{sup -1}. The results indicate that, while germination inhibition of P. comosa may be enhanced by the chemical dispersal of oil response varies with type of both oil and oil dispersant. (author)
Functional activation of {beta}-catenin/Tcf signaling plays an important role in early events in carcinogenesis. We examined the effect of naringenin against {beta}-catenin/Tcf signaling in gastric cancer cells. Reporter gene assay showed that naringenin inhibited {beta}-catenin/Tcf signaling efficiently. In addition, the inhibition of {beta}-catenin/Tcf signaling by naringenin in HEK293 cells transiently transfected with constitutively mutant {beta}-catenin gene, whose product is not phosphorylated by GSK3{beta}, indicates that its inhibitory mechanism was related to {beta}-catenin itself or downstream components. To investigate the precise inhibitory mechanism, we performed immunofluorescence, Western blot, and EMSA. As a result, our data revealed that the {beta}-catenin distribution and the levels of nuclear {beta}-catenin and Tcf-4 proteins were unchanged after naringenin treatment. Moreover, the binding activities of Tcf complexes to ...
Morusin is a pure compound isolated from root bark of Morusaustralis (Moraceae). In this study, we demonstrated that morusin significantly inhibited the growth and clonogenicity of human colorectal cancer HT-29 cells. Apoptosis induced by morusin was characterized by accumulation of cells at the sub-G_1 phase, fragmentation of DNA, and condensation of chromatin. Morusin also inhibited the phosphorylation of IKK-#alpha#, IKK-#beta# and I#kappa#B-#alpha#, increased expression of I#kappa#B-#alpha#, and suppressed nuclear translocation of NF-#kappa#B and its DNA binding activity. Dephosphorylation of NF-#kappa#B upstream regulators PI3K, Akt and PDK1 was also displayed. In addition, activation of caspase-8, change of mitochondrial membrane potential, release of cytochrome c and Smac/DIABLO, and activation of caspase-9 and -3 were observed at the early time point. Downregulation in the expression of Ku70 and XIAP was exhibited afterward. Caspase-8 ...
Metal cations of arsenic, antimony, tin, manganese, zinc, cadmium, indium, and thallium have been evaluated in a preliminary way as possible3 inhibitors for controlling denting corrision observed in steam generators used with pressurized water reactors (PWR). The rationale for this approach was based upon the well-known inhibition effects of metal cations on corrosion rates in electrolyte/metal systems. A review of corrosion inhibition by metal cations (H. Leidheiser, Jr., Corrosion 36, 339 (1982)) has identified eleven inhibition mechanisms. The major test methods used for this evaluation were: (1) Isothermal capsule tests of carbon/steel/Inconel 600 tube bulging rates at temperatures up to 288/sup 0/C in seawater/copper-nickel chloride bulge-accelerating solutions. (2) Immersion weight-loss tests of steel coupled to Inconel 600 in boiling (102/sup 0/C) 3% sodium chloride solutions. In addition, electrochemical measuremens ...
The objective of this work was to investigate the efficiency of imidazole and its derivatives 4-methylimidazone, 4-methyl-5-hydroxymethylimidazone, 1-phenyl-4-methylimidazone, and 1-(p-tolyl)-4-methylimidazole for corrosion inhibition of copper in 0.5 M hydrochloric acid. Corrosion inhibition was studied using potentiodynamic methods. These studies have shown that 1-(p-tolyl)-4-methylimidazole has the best inhibitory efficiency. Activation energies were obtained by measuring the temperature dependence of the corrosion current. The activation energies in the presence of the various inhibitors are low (3--5 kJ/mol), with the best inhibitor showing the highest value. The adsorptive behavior of the imidazole derivatives on the copper electrode surface follows a Freundlich-type isotherm. The standard free energies of adsorption are also low (14--16 kJ/mol), indicating that imidazole and its derivatives physisorb on the copper surface. Possible ...
The objective of this work was to investigate the efficiency of imidazole derivatives for corrosion inhibition of copper in 0.5 M hydrochloric acid. Corrosion inhibition was studied using impedance spectroscopy. Imidazole and its derivatives 4-methylimida-zole, 4-methyl-5-hydroxymethylimidazole, 1-phenyl-4-methylimidazole, 1-(p-tolyl)-4-methylimidazole were investigated. These studies have shown that 1-(p-tolyl)-4-methylimidazole is the best inhibitor in this series and that it acts as mixed inhibitor. The nature of the chemical interaction between these molecules and the copper surface was investigated by Cu exposed to solutions having two very different pH values: 0.5 M HCl and unbuffered purified water. X-ray photoelectron spectroscopy and secondary ion mass spectrometry were used to explore the nature of the interaction. Possible mechanisms of corrosion inhibition for these molecules are discussed.
There is a plethora of new silver-containing dressings on the market today. Various manufacturers attempt to show that their dressings are the most efficacious and therefore should be preferentially employed by health care workers based on the results of their in vitro tests. However, there have been no studies that clearly identify which tests are appropriate for comparison purposes. The purpose of this study was to determine which in vitro test is most appropriate for evaluating the antimicrobial efficacy of silver-containing dressings. This was done by testing seven silver-containing dressings and two non-silver-containing topical agents against 17 clinically relevant microorganisms using zone of inhibition assays and time-kill kinetic assays in complex media. The results for the two assays were then correlated to determine whether the methods generated similar results. It was determined that the two methods do not correlate at all. This is most likely a result ...
Abstract. Objective: Lapatinib (Tykerb, GW572016), a potent inhibitor of the catalytic activities of epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) (ErbB2), inhibits population growth of selected EGFR and HER2 overexpressing cell lines. Previous studies with a small number of cell lines suggest a correlation between overexpression of EGFR and/or HER2 and sensitivity to growth inhibition by lapatinib; however, the precise determinants of lapatinib selectivity for tumour and/or other cells remain unclear. Materials and methods: To clarify the determinants of its selectivity in cultured cells, lapatinib-induced cell population growth inhibition and relative EGFR and HER2 protein expression were quantified in 61 different human tumour cell lines fro...
Sepsis induced by methicillin-resistant Staphylococcus aureus (MRSA) has worse outcome because of multiresistance to a large group of antibiotics, which may lead to death from septic shock. In the present study, we firstly found that artesunate in combination with oxacillin was capable of protecting mice challenged with live MRSA WHO-2 (WHO-2) and the protection was related to the reduced TNF-a and IL-6 levels and decreased bacterial load. Based on above results, artesunate was further investigated from two aspects in vitro, anti-inflammation effect and antibacterial enhancement effect on antibiotics. Artesunate not only inhibited TNF-a and IL-6 release but also inhibited mRNA and protein expressions of TLR2 and Nod2, two important receptors, in murine peritoneal macrophages stimulated wit...
Niobium carbide can be used to inhibit WC grain growth in hardmetal. The performance of a NbC powder produced at low temperature by solid-gas reaction (an experimental powder) as WC grain growth inhibitor is compared with that of a commercial NbC powder. It is verified that NbC effectively inhibits heterogeneous WC coarsening. This results in an increase in hardness. The commercial and experimental NbC powders exhibit a comparable performance in inhibiting the WC grain coarsening, in spite of a significant difference in particle size and shape. The commercial NbC powder is very fine while the experimental one is coarse and porous, but its crystallites are finer than those of the commercial product. The milling procedure used to prepare the alloys is able to reduce the particle size of the experimental NbC, and thus guarantee a dispersion of the particles with a quality level comparable to that found for the alloy prepared ...
Self-assembled monolayer (SAM) of histidine (His) was prepared on copper surface at various pH values. The effect of KI additives on corrosion protection efficiency of His SAM was also studied. The protection abilities of these films against copper corrosion in 0.5 M HCl aqueous solution were investigated using electrochemical impedance spectroscopy and polarization techniques. The results show that the film formed on the electrode is more stable at pH = 10 than that at other pH values. When the iodide ions were added into the His self-assembly solution (pH = 10), protection efficiency was further improved. The inhibition mechanism has been discussed by quantum chemical calculations.
Four-enzyme section of the shikimate pathway (Aro B, D, E, and K) of Streptococcus pneumoniae has been studied. Kinetic properties of the individual enzymes and three- and four-enzyme linked reactions have been characterized in vitro. On the basis of the data measured in spectrophotometric and LC-MS experiments, kinetic mechanisms of the enzymes have been suggested and all kinetic parameters have been identified. Kinetic models for these three- and four-enzyme sections of the shikimate pathway have been constructed and validated. The model of the four-enzyme section of shikimate pathway has been employed to design an inhibition-sensitive reconstituted pathway for a high-throughput screening effort on the shikimate pathway. It was demonstrated that using the model it was possible to optimize this reconstituted pathway in such a way to provide equal sensitivity of the enzymes to inhibition. PMID:16921527
A solvent extraction method was developed to obtain methanolic extracts rich in antioxidants from banana peel. Central composite design ''2^3+star'' and response surface methodology were used in order to optimise the number of extraction steps, extraction temperature and extraction time. The number of extractions was statistically the most significant factor in scavenging activity against both DPPH? and ABTS?^+ radicals and in the inhibition of TBARS formation, while the extraction temperature had an important impact on the capacity to prevent b-carotene bleaching. However, the effect of the extraction time on antioxidant activity was less important. The optimum values of the factors that influence the capacity to scavenge DPPH? and ABTS?^+ radicals or to inhibit b-carotene bleaching were ...
Inhibition of adipogenesis and lipid accumulation has a very crucial role to prevent obesity. Low molecular weight (LMW) chitosan is known to inhibit fat accumulation and adipogenesis. (N,O)-sulfated chitosan is a sulfation derivative of chitosan oligomers, and its anti-obesity effect is not yet reported. In this study, it has been reported that (N,O)-sulfated chitosan significantly decreased lipid accumulation, an indicator for adipogenesis, in differentiating 3T3-L1 preadipocyte cells. Furthermore, mRNA expressions and protein levels of key adipogenic markers such as peroxisome prolifetor-activated receptor (PPAR)-@c and CCAAT-enhancer binding protein (C/EBP)-@a were considerably decreased by (N,O)-sulfated chitosan treatment. As a consequence, sulfation of LMWC remarkably increased its ...
Eight selected sulfonamide drugs were investigated as inhibitors of heat shock protein 90 (Hsp90). The investigation included simulated docking experiments to fit the selected compounds within the binding pocket of Hsp90. The selected molecules were found to readily fit within the ATP-binding pocket of Hsp90 in low-energy poses. The sulfonamides torsemide, sulfathiazole, and sulfadiazine were found to inhibit the ATPase activity of Hsp90 with IC50 values of 1.0, 2.6, and 1.5 mM, respectively. Our results suggest that these well-established sulfonamides can be good leads for subsequent optimization into potent Hsp90 inhibitors.
The effect of sodium gluconate anion (SG) on the corrosion and scale inhibition of ordinary steel in simulated cooling water has been studied using weight loss, polarisation curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) techniques. SG was studied in concentration from 10{sup -4} M to 10{sup -1} M. Results obtained reveal that SG perform excellently as corrosion and scaling inhibitor for ordinary steel in simulated cooling water. An increase of SG concentration leads to the increase of the corrosion potential towards the positive direction. The inhibition efficiency was a low temperature dependence. The inhibitor mechanism was treated as an adsorption process according to Langmuir adsorption isotherm. The SEM/EDAX data show that was a corrosion and scale inhibitor.
The effect of sodium gluconate anion (SG) on the corrosion and scale inhibition of ordinary steel in simulated cooling water has been studied using weight loss, polarisation curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) techniques. SG was studied in concentration from 10-4M to 10-1M. Results obtained reveal that SG perform excellently as corrosion and scaling inhibitor for ordinary steel in simulated cooling water. An increase of SG concentration leads to the increase of the corrosion potential towards the positive direction. The inhibition efficiency was a low temperature dependence. The inhibitor mechanism was treated as an adsorption process according to Langmuir adsorption isotherm. The SEM/EDAX data show that was a corrosion and scale inhi...
The shrinking core model is examined for gas-solid noncatalytic reactions with a self-inhibited rate form and it is shown that multiple reaction pathways are possible for solid particles reacted under identical conditions. The observed reaction rate can have up to two discontinuities (jumps) during reaction for particles of spherical and cylindrical shape. The geometric instability analysis reveals that the reaction interface is stable under a very limited set of conditions only for solid particles of slab geometry. For a sphere or cylinder at large Biot numbers the reaction interface is always potentially unstable. This model provides a plausible explanation for gas-solid reactions which exhibit erratic shrinking core behavior.
Pilot plant tests have been conducted to evaluate sodium thiosulfate as an oxidation inhibition additive in five lime/limestone slurry flue gas desulfurization processes. It was found that the oxidation rate of absorbed sulfur dioxide (SO/sub 2/) was reduced by more than 50 percent in the presence of 100 to 200 ppm of thiosulfate ion in the scrubbing slurry. Calcium sulfate dihydrate (gypsum) scaling was eliminated and the unsaturated (with respect to gypsum) operation mode was maintained by the addition of sodium thiosulfate. Other benefits of sodium thiosulfate addition observed at the pilot plant included improvement in solids dewatering properties for limestone processes.
The dependence of the inhibiting action of some surface active organic substances (SAOS) on the pitting- formation potential epsilonsub(p) has been investigated for the steel Kh25T. The study has been performed by potentiostatic method using the H_2SO_4 0.1-n-solution doped by NaCl, Na_2SO_4, in the presence of SAOS of different classes. As epsilonsub(p) shifts in positive direction from +0.6 to +1.1 V, the inhibiting action of the SAOS series (o-oxyquinoline) increases gradually till some critical potential above which SAOS favour pitting destruction of steel. This phenomenon should be considered in anodic protection in SAOS-doped solutions.
Objective To evaluate the inhibitory property of de-glycyrrhizinated extract of Glycyrrhiza glabra root and its phytoconstituents (glabridin, isoliquiritigenin and glycyrrhizin) on LPS-induced production of pro-inflammatory mediators. Materials and methods Inhibitory effect of G. glabra extract and its phytoconstituents were studied on lipopolysaccharide (LPS)-induced nitric oxide (NO), interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) levels in J774A.1 murine macrophages. Results G. glabra and isoliquiritigenin significantly inhibited LPS stimulated NO, IL-1 beta and IL-6 production. Glabridin showed significant inhibition of NO and IL-1 beta release, but failed to attenuate IL-6 levels at the tested concentrations. In addition, glycyrrhizin did not exhibit inhibitory response towar...
In this study, we investigated the kinetics of linoleic acid production via lipase-mediated hydrolysis of corn DDGS oil in a batch reactor with continuous mechanical agitation and developed a kinetic model that incorporated the product inhibition to study the complete hydrolysis. The model agreed very well with observed data; though situations with low enzyme dosage or low stirring rates were modeled successfully without product inhibition, actual product concentration in such situations was too low to exert any inhibitory effects. Increasing the enzyme concentration increased hydrolysis, and beyond certain enzyme concentrations, effects tended to fade away because of excessive enzyme desorption from the interface. An enzyme dosage within the range of 40-60KLU/L of oil dispersion could be ...
The observed inhibition of M4 transitions in A approx. 90 nuclei has represented a long standing theoretical problem. In particular by calculating first- and second-order configuration mixing contributions to the inhibited M4 lifetimes of /sup 89/Y and /sup 87/Sr, it is found that the first-order perturbative treatment of the residual interaction usually used in shell-model calculations is unjustified in this case. Using random-phase approximation techniques, the renormalization effects of collective (''giant'') M4 resonances in /sup 88/Sr on the low energy M4 transitions in /sup 89/Y and /sup 87/Sr are investigated. It is concluded that the observed retardation of M4 lifetimes in these nuclei is consistent with the manifestation of nuclear spin polarization.
Dilute caustic high-level radioactive waste slurries can induce pitting corrosion in carbon steel. Cyclic potentiodynamic polarization tests were conducted in simulated and actual waste solutions to determine minimum concentrations of sodium nitrate which inhibit pitting in ASTM A537 class 1 steel exposed to these solutions. Susceptibility to pitting was assessed through microscopic inspection of specimens and inspection of polarization scans. Long-term coupon immersion tests were conducted to verify the nitrite concentrations established by the cyclic potentiodynamic polarization tests. The minimum effective nitrite concentration is expressed as a function of the waste nitrate concentration and temperature.
PP2B is a Ca2+/calmodulin-dependent protein phosphatase that is ubiquitously expressed in mammals. Among other actions, it is an effector mechanism in NMDA-mediated glutamate neurotransmission as well as a regulator of GSK3? and MAPK signaling cascades. Because all of these mechanisms have demonstrable roles in the control of circadian rhythyms, we hypothesized that PP2B would be a key regulator of rhythm generation and entrainment, and that through inhibition of its phosphatase activity, the circadian system would be affected by immunosuppressant drug therapy. We report here that immunosuppressant drugs (cyclosporin A, FK506) (1) block the circadian responses to light that underlie photic entrainment; (2) produce circadian phase shifts with a characteristic nonphotic profile; and (3) disr...
Certain fluorocarbons, such as difluorodichloromethane (FC 12), depress the cardiovascular system by diminution of all the transmembrane ionic conductances in cardiac tissues. Does FC 12 also inhibit active transport and thus enzymatic activity and cellular energy. We measured phosphocreatine (PC), adenosine triphosphate (ATP) and cyclic adenosine monophosphate (AMPc) in rat hearts. Rats were randomly divided into 4 groups; 2 control groups: one breathing a mixture of oxygen (21%) and nitrogen (79%) (group C) and the other breathing the same mixture but simultaneously perfused with 1 microgram/kg/min. epinephrine (groupe E-C); 2 trial groups T and E-T where nitrogen was replaced by FC 12. The maximal FC 12 concentration of 720 micrograms/ml in arterial blood produced no significant difference in the concentrations of these three metabolites compared with controls.
The anticonvulsant drugs carbamazepine, phenobarbital, trimethadione, valproic acid and ethosuximide at pharmacologically relevant concentrations inhibit (/sup 3/H)diazepam binding to astrocytes in primary cultures but have much less effect on a corresponding preparation of neurons. Phenytoin as well as pentobarbital (which is not used chronically as an anticonvulsant) are equipotent in the two cell types. The convulsants picrotoxinin and pentylenetetrazol, the convulsant benzodiazepine RO 5-3663 and the two convulsant barbiturates DMBB and CHEB similarly inhibit diazepam binding to astrocytes but have little effect on neurons. On the basis of these findings it is suggested that these convulsants and anticonvulsants owe at least part of their effect to an interaction with the astrocytic benzodiazepine receptor, perhaps by interference with a calcium channel.
An energy saving dc-dc converter circuit is disclosed having two energy efficient means which operate in tandem, an energy conserving means and a voltage doubling means. These energy efficient means are applied in combination with elements commonly found in dc-dc converter circuits, namely an ac voltage generator, a transformer for stepping up the generated ac voltage, and means for storing the converted dc voltage. The energy conserving means is connected to the dc voltage storage means. It comprises a resettable inhibit circuit which cuts off the provision of dc voltage for conversion for a predetermined interval when the output of the converter exceeds a predetermined level. The voltage doubling means is reponsive to outputs of the inhibit circuit of the energy conserving means and the ac voltage generator. It provides a phase inverted waveform of the generated ac voltage on one of two leads to the ac voltage step-up transformer.
The effects of orthovanadate on the uptake of sucrose by Ricinus cotyledons and on sucrose-coupled proton influx were measured in order to gain insight into the relationship to the plasma membrane proton pump. Vanadate had no effect on short-term sucrose uptake. In long-term experiments (> 30 min) sucrose uptake was progressively inhibited, but only at high external sucrose concentrations. Vanadate did not affect proton efflux pumping in the absence of sucrose and neither did it change the initial rate of sucrose-coupled proton influx. However, it enhanced the maximal level of sucrose-induced alkalization of the medium at all sucrose concentrations tested. This is interpreted as an inhibiting effect of vanadate on the proton pump that recycles protons during sucrose-proton cotransport. The sensitivity towards vanadate indicates that this proton pump is an ATPase. A second proton-translocating system, that is insensitive to vanadate, is ...
Purpose: To secure the reactor operation safety by the provision of a fluid pressure detecting section for control rod driving fluid and a control rod interlock at the midway of the flow pass for supplying driving fluid to the control rod drives. Constitution: Between a driving line and a direction control valve are provided a pressure detecting portion, an alarm generating device, and a control rod inhibition interlock. The driving fluid from a driving fluid source is discharged by way of a pump and a manual valve into the reactor in which the control rods and reactor fuels are contained. In addition, when the direction control valve is switched and the control rods are inserted and extracted by the control rod drives, the pressure in the driving line is always detected by the pressure detection section, whereby if abnormal pressure is resulted, the alarm generating device is actuated to warn the abnormality and the control rod inhibition ...
The antioxidant properties of magnolol and honokiol were evaluated in the experimental systems of reducing ONOO^- and ^1O"2, bleaching @b-carotene in linoleic acid (LH) emulsion, and trapping 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS^+?) and 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH), and then were applied to inhibit the oxidation of DNA induced by Cu^2^+/glutathione (GSH) and 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH). Magnolol and honokiol were active to reduce ONOO^- and ^1O"2. Honokiol showed a little higher activity to protect LH and to inhibit Cu^2^+/GSH-induced oxidation of DNA than magnolol. In addition, honokiol exhibited higher activities to trap ABTS^+? and DPPH than magnolol. In particular, honokiol trapped 2.5 radicals while magnolol o...
Glucose homeostasis requires the tight regulation of glucose utilization by liver, muscle and white or brown fat, and glucose production and release in the blood by liver. The major goal of maintaining glycemia at -5 mM is to ensure a sufficient flux of glucose to the brain, which depends mostly on this nutrient as a source of metabolic energy. This homeostatic process is controlled by hormones, mainly glucagon and insulin, and by autonomic nervous activities that control the metabolic state of liver, muscle and fat tissue but also the secretory activity of the endocrine pancreas. Activation or inhibition of the sympathetic or parasympathetic branches of the autonomic nervous systems are controlled by glucose-excited or glucose-inhibited neurons located at different anatomical sites, mainl...
The usage of biosorbents allows separation of scandium and yttrium from each other and from Fe, Al, Ti, Si, and Ca in hydrometallurgical processing of ores and wastes. It was shown that sorption of scandium and yttrium increased with the increase of pH of solution. Initial rate of scandium sorption depended on the biomass type; however 85-98% of scandium was sorbed within 10-30 min with most biomass types tested. The presence of aluminium, iron (III), and titanium in the solution inhibited sorption of scandium and particularly yttrium. After four cycles of sorption, 98.8% of scandium and 87% of yttrium was extracted from red mud leach solution by the biomass of Saccharomyces cerevisiae and Aspergillus terreus, respectively. Selectively of the process of scandium and yttrium recovery could be achieved during sorption and also desorption, when solubilization of sorbed associated elements was inhibited by high pH values. (Author).
Moso bamboo (Phyllostachys pubescens) is widely distributed in the acid soil region of Southern China, where great potential of aluminum (Al) toxicity exists. To evaluate the Al tolerance of Moso bamboo, seed germination and root elongation were compared with two rice cultivars, and physical and physiological damages were examined under various levels of Al stress. Results showed that Moso bamboo seed germination was inhibited when Al concentration increased to 500 ?M, and the median lethal concentration was 2,000??M. Comparatively, the rice seed germination was not inhibited even at a concentration of 2,000??M Al. Aluminum accumulated mainly in the cell wall of root apices, and entered into protoplasts as treating time prolonged and/or Al concentration increased, which resulted in apoptos...
Abstract The inhibitory effect of the extract from Magnolia officinalis (MOE) against L. monocytogenes, S. faecalis, E. coli, S. typhimurium, S. aureus and B. anthracis by paper-diffusion methods and the characterization of the mutton immersed in different concentrations of the MOE during storage were evaluated in this paper. The results showed that MOE could significantly inhibit the growth of S. aureus, S. faecalis, B. anthracis and E. coli, and their MIC was 0.02-mg/mL, 0.03-mg/mL, 0.05-mg/mL and 0.10-mg/mL, respectively. MOE showed weak inhibition for the S. typhimurium. The mutton treated with 2%, 4% and 6% MOE resulted in suppression in the increase of total volatile base nitrogen, thiobarbituric acid reactive substance, and the growth of Enterobacteriaceae, Pseudomonas. The cooled m...
Culturing human prostate PC-3 cells for 4, 24, or 72 h in the presence of 5,8,11,14-eicosatetraynoic acid (ETYA), an inhibitor of arachidonic acid metabolism and cholesterol biosynthesis, markedly altered the morphology and reduced the number of mitochondria in the treated cells. Using quantitative electron microscopic morphometry, we documented changes in the number, form, area, matrix density, and integrity of the cristae and limiting membranes of mitochondria in cells cultured with ETYA. The inhibition of cholesterol synthesis or the substitution of ETYA for polyunsaturated fatty acids in the inner membrane may participate in the disruption of the mitochondria, which resembles the morphologic sequelae of oxidative stress. If sufficiently extensive, these changes could contribute to the inhibition of cellular proliferation by ETYA.
This patent describes an improved zinc electrode for a rechargeable zinc-air battery comprising an outer frame and a porous foam electrode support within the frame which is treated prior to the deposition of zinc thereon to inhibit the formation of zinc dendrites on the external surface thereof. The outer frame is provided with passageways for circulating an alkaline electrolyte through the treated zinc-coated porous foam. A novel rechargeable zinc-air battery system is also disclosed.
We tested the hypothesis that the basal release of nitric oxide (NO) from endothelial cells modulates contractile activity in the corpus cavernosum (CC) via inhibition of the RhoA/Rho-kinase signaling...Full Text Available
Thermogalvanic corrosion of St3 steel in a temperature range from 25 to 50{degrees}C with a 3.84{degrees}C/cm gradient was studied in a neutral media flow. It is shown that the thermogalvanic effect on the pitting corrosion of water-cooled heat exchangers is decisive but dual. Depending on the composition of the cooling medium, thermogalvanic corrosion may either enhance (0.5 M NaCl) or inhibit (tap water) pitting corrosion.
A chemical equilibrium model is used, implemented in a compact FORTRAN package called HITEQ, to investigate possible mineral deposition related to prereinjection treatment of Cerro Prieto brines for silica removal. Large saturation ratios of the treated brines with respect to several minerals are indicated by these computations. As a remedy, an inexpensive CO/sub 2/ removal scheme aimed at inhibiting carbonate mineral precipitation is proposed. This scheme is quantitatively discussed with the aid of HITEQ. It is concluded that the proposed treatment is both technically and economically feasible.
The effect of in vitro and in vivo administration of ethanol on the binding of "3"5S-t-butyl-bicyclophosphorothionate ("3"5S-TBPS) to cortical brain membranes of C57B1 mice was investigated using KCl (100 mM) containing assay media. The in vitro addition of ethanol produced a dose-dependent inhibition of basal "3"5S-TBPS binding. In the presence of chloride ions, GABA and pentobarbital had a biphasic action (stimulation followed by inhibition) on "3"5S-TBPS binding, whereas diazepam only stimulated the binding. Ethanol reduced the stimulatory effects of GABA and pentobarbital in a dose-dependent manner, but had no effect on the enhancement of "3"5S-TBPS binding produced by diazepam. "3"5S-TBPS binding to cortical brain membranes was inhibited by the putative Cl"- channel blocking agent DIDS. This inhibitory action of DIDS was significantly, and dose-dependently reduced by ethanol (#<=# 100 mM ethanol). Chronic ethanol ...
Purpose.To report the increased production of extracellular transforming growth factor β-induced protein (TGFBIp) by human corneal epithelial cells (HCECs) after induction...Full Text Available
A novel class of pyrrolidinyl-acetyleneic thieno[3,2-d]pyrimidines has been identified which potently inhibit the EGFR and ErbB-2 receptor tyrosine kinases. Synthetic modifications of the pyrrolidine carbamate moiety result in a range of effects on enzyme and cellular potency. In addition, the impact of the absolute stereochemical configuration on cellular potency and oral mouse pharmacokinetics is described.
Two novel crystal structures of Zea mays protein kinase CK2α catalytic subunit, one in complex with the specific inhibitor 4,5,6,7-tetrabromobenzotriazole (TBB) and another...Full Text Available
A multiple metal oxide sorbent supported on a zeolite of substantially silicon oxide is used for the desulfurization of process gas streams, such as from a coal gasifier, at temperatures in the range of about 1200.degree. to about 1600.degree. F. The sorbent is provided by a mixture of copper oxide and manganese oxide and preferably such a mixture with molybdenum oxide. The manganese oxide and the molybdenum are believed to function as promoters for the reaction of hydrogen sulfide with copper oxide. Also, the manganese oxide inhibits the volatilization of the molybdenum oxide at the higher temperatures.
Matrix metalloproteinase (MMP) plays a crucial role in periodontal disease and is up-regulated by oral Gram-negative, pathogen-derived LPS. In this study, we reported that simvastatin, a 3-hydroxyl-3-methylglutaryl-CoA...Full Text Available
The aim of this study is to determine the effects of silver nanoparticles (Ag-NP) on vascular endothelial growth factor (VEGF)-and interleukin-1 beta (IL-1β)-induced vascular permeability, and...Full Text Available
Non-alcoholic fatty liver disease is a serious health problem linked to obesity and type 2 diabetes. To investigate the biological outcome and therapeutic potential of hepatic fatty acid uptake inhibition,...Full Text Available
Inhibition of large conductance calcium-activated potassium (BKCa) channels mediates, in part, oxygen sensing by carotid body type I cells. However, BKCa channels remain active...Full Text Available
Regulatory T (T reg) cells exert powerful down-modulatory effects on immune responses, but it is not known how they act in vivo. Using intravital two-photon laser scanning microscopy we determined that,...Full Text Available
We have found that the methionine repression of the ..beta..-subunit gene expression is not due to degradation of the ..beta..-subunit but is due to an effect on synthesis of the ..beta..-subunit. The effect of methionine on the synthesis of the ..beta..-is due to an inhibition of ..beta..-subunit mRNA synthesis. 3 references, 1 figure.
The inhibitor action of unbranched polyamines on corrosion of low-carbon steel in 0.5 M sulfuric acid is studied through potentiostatic polarization curves. It is shown that the inhibitor efficiency I depends on the polyamine concentration and molecular structure. The quantum-mechanical calculations of molecular properties are accomplished through the MNDO method. Correlation between the measured I and physicochemical properties of the polyamine inhibitors in protonized and nonprotonized form is found with application of the general perturbation theory
A pro-drug 8 of a synthetic analog 7 is more active in its anti-proliferative activity against human breast cancer MDA-MB-231 cells possessing high Catechol-O-methyltransferase...Full Text Available
A super-hydrophobic coating was prepared by combining a rigid base film with crater-like hemispherical holes and acicular nanoparticles. The acicular boehmite powder provides a high contact angle on the film surface. The rigid base film with crater-like hemispherical holes inhibits the rapid decrease of contact angle by surface rubbing. The combination of different roughness is an effective method for improving the abrasion resistance of super-hydrophobic films.
BackgroundRecent studies have suggested that the Src inhibitor dasatinib preferentially inhibits the growth of breast cancer cells of the basal-like subtype. To clarify this finding...Full Text Available
The pitting corrosion resistance of three different types of stainless steel implanted with silicon is investigated using the potentiokinetic polarization technique. The specimens are tested in 3% NaCl and 0.1 N HCl solutions. Silicon ion implantation inhibits pitting corrosion of the steels in both aqueous media. The corrosion resistance depends on the silicon dose. Post implantation annealing only slightly alters the localized corrosion. (author).
1. We studied the effects of flash photolysis on the novel enantiomeric cardiac inotropes EMD 57033 (a calcium sensitizer) and EMD 57439 (a phosphodiesterase III inhibitor) in rat isolated ventricular...Full Text Available
We have isolated a 4.785 Da protein from the nacreous layer of the sea snail Haliotis laevigata (greenlip abalone) shell after demineralization with acetic acid. The sequence of 41...Full Text Available
Soluble epoxide hydrolase (sEH) plays an important role in the metabolism of endogenous chemical mediators involved in the regulation of blood pressure and inflammation. 1,3-Disubstituted ureas with a polar group located on the fifth atom from the carbonyl group of urea function are active inhibitors of sEH both in vitro and in vivo. However, their limited solubility in water and relatively high melting point lead to difficulties in formulating the compounds and poor in vivo efficacy. To improve these physical properties, the effect of structural modification of the urea pharmacophore on the inhibition potencies, water solubilities, octanol/water partition coefficients (log P), and melting points of a series of compounds was evaluated. For murine sEH, no loss of inhibition potency was observed when the urea pharmacophore was modified to an amide function, while for human sEH 2.5-fold decreased inhibition was obtained in the ...
ObjectivesObjectives Not AvailableDescriptionOne significant research challenge posed by the growing number of older people in the population concerns the mobility-related problems which increase with age, inhibit independence, and can be a prime cause of admission to expensive institutional settings. The scope for engineering advances, particularly in the field of rehabilitation and assistive technology, is immense. The challenge is to produce aids, devices and products that are attractive to older people themselves, since without such [continued...
We demonstrate the nonuniqueness of the basic assumptions leading to spiral structure in self-propagating star formation models. Even in the case where star formation occurs purely spontaneously and does not propagate, we have generated spiral structure by adopting the radically different assumption where star formation is systematically inhibited.
In monocytes, sulfatide, a lipid from Mycobacterium tuberculosis, blocked priming for enhanced release of superoxide (O2-) by the macrophage activating factors lipopolysaccharide, gamma interferon,...Full Text Available
Most antibodies to factor VIII have recently been shown to react with discrete regions of the factor VIII light chain (within the C2 domain) and/or the factor VIII heavy chain (within the amino-terminal...Full Text Available
BackgroundMicroRNAs (miRNAs) are important regulators that play key roles in tumorigenesis and tumor progression. A previous report has shown that let-7 family members can act as...Full Text Available
A composition of matter to treat particles entrained in flue gas, is described comprising: a caustic liquid used to adjust resistivity of the entrained particles; and inert particulate matter supporting the caustic liquid for inhibiting chemical action of the caustic liquid until used to adjust the resistivity of the entrained particles, the inert particulate matter supporting sufficient caustic liquid to adjust the resistivity of the entrained particles.
Administration of minocycline (MN), a tetracycline antibiotic, produces a black pigment in the thyroids of humans and several species of experimental animals and antithyroid effects in rodents. We have previously shown that these effects appear to be related to interactions of MN with thyroid peroxidase (TPO), the key enzyme in thyroid hormone synthesis. In the present study, the mechanisms for inhibition of TPO-catalyzed iodination and coupling reactions by MN were investigated. 37 refs., 7 figs., 3 tabs.
In diabetes complications, CCN-2 (known originally as CTGF) has been implicated in diabetic nephropathy both as a marker and a mediator of disease. This commentary addresses CCN-2 in diabetic nephropathy, in the context of the recent publication of the first human study to inhibit CCN-2 bioactivity in diabetic kidney disease.
Vacuolar ion channels in guard cells play important roles during stomatal movement and are regulated by many factors including Ca2+, calmodulin, protein kinases, and phosphatases....Full Text Available
Smooth muscle cell (SMC) proliferation and migration are key processes that occur in the pathogenesis of atherosclerosis and post-angioplasty restenosis. In the present study, we designed locked nucleic...Full Text Available
The long pentraxin PTX3 has multiple roles in innate immunity. For example, PTX3 regulates C1q binding to pathogens and dead cells and regulates their uptake by phagocytes. It also inhibits P-selectin-mediated...Full Text Available
The nuclear lamina proteins, prelamin A, lamin B, and a 70-kD lamina-associated protein, are posttranslationally modified by a metabolite derived from mevalonate. This modification can be inhibited by treatment with (3-R,S)-3-fluoromevalonate, demonstrating that it is isoprenoid in nature. We have examined the association between isoprenoid metabolism and processing of the lamin A precursor in human and hamster cells. Inhibition of 3-hydroxy-3-methylglutaryl coenzyme A reductase by mevinolin (lovastatin) specifically depletes endogenous isoprenoid pools and inhibits the conversion of prelamin A to lamin A. Prelamin A processing is also blocked by mevalonate starvation of Mev-1, a CHO cell line auxotrophic for mevalonate. Moreover, inhibition of prelamin A processing by mevinolin treatment is rapidly reversed by the addition of exogenous mevalonate. Processing of prelamin A is, therefore, dependent on ...
From the dried fruiting bodies of the mushroom Armillaria luteo-virens, a dimeric lectin with a molecular mass of 29.4 kDa has been isolated. The purification procedure involved (NH{sub 4}){sub 2}SO{sub 4} precipitation, ion exchange chromatography on DEAE-cellulose, CM-cellulose, and Q-Sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. The hemagglutinating activity of the lectin could not be inhibited by simple sugars but was inhibited by the polysaccharide inulin. The activity was stable up to 70 {sup o}C but was acid- and alkali-labile. Salts including FeCl{sub 3}, AlCl{sub 3}, and ZnCl{sub 2} inhibited the activity whereas MgCl{sub 2}, MnCl{sub 2}, and CaCl{sub 2} did not. The lectin stimulated mitogenic response of mouse splenocytes with the maximal response achieved by 1 {mu}M lectin. Proliferation of tumor cells including MBL2 cells, HeLa cells, and L1210 cells was ...
The present study was undertaken to determine the involvement of calcium-protein kinase C pathway in the mechanism of action of Escherichia coli heat stable enterotoxin (STa) apart from STa-induced activation of guanylate cyclase in human colonic carcinoma cell line COLO-205, which was used as a model cultured cell line to study the mechanism of action of E. coli STa. In response to E. coli STa, protein kinase C (PKC) activity was increased in a time-dependent manner with its physical translocation from cytosol to membrane. Inhibition of the PKC activity in membrane fraction and inhibition of its physical translocation in response to IP_3-mediated calcium release inhibitor dantrolene suggested the involvement of intracellular store depletion in the regulation of PKC activity. Among different PKC isoforms, predominant involvement of calcium-dependent protein kinase C (PKC#alpha#) was specified using isotype-specific pseudosubstrate, which showed ...
N-Hydroxy-N′-(4-n-butyl-2-methylphenyl)formamidine (HET0016) is a potent inhibitor of 20-hydroxyeicosatetraenoic acid (20-HETE) formation by specific cytochrome P450 (CYP) isoforms....Full Text Available
Interferon-γ (IFN-γ) has been shown to enhance anti-tumor immunity and inhibit the formation of bone-resorbing osteoclasts. We evaluated the role of IFN-γ in bone metastases,...Full Text Available
The authors have found that heat-inactivated serum (57/sup 0/C for 1 hour) from normal chickens reduces the proliferation of mitogen-stimulated chicken and murine splenocytes as well as some transformed mammalian lymphoblastoid cell lines. Greater than a 50% reduction in /sup 3/H-thymidine incorporation was observed when concanavalin A (Con A)-activated chicken splenocytes that were cultured in the presence of 10% autologous or heterologous serum were compared to mitogen-stimulated cells cultured in the absence of serum. Normal chicken serum (10%) also caused greater than 95% suppression of /sup 3/H-thymidine incorporation by bovine (EBL-1 and BL-3) and gibbon ape (MLA 144) transformed lymphoblastoid cell lines. The only cell line tested that was not inhibited by chicken serum was an IL-2-dependent, murine cell line. Chicken serum also inhibited both /sup 3/H-thymidine incorporation and IL-2 synthesis by Con A-activated murine splenocytes. ...
BackgroundhTERTC27 is a 27 kDa C-terminal polypeptide of human telomerase reverse transcriptase that has previously been shown to reduce tumorigenicity of HeLa cells and suppress...Full Text Available
The herbicide atrazine is a known immunotoxicant and an inhibitor of human natural killer (NK) cell lytic function. The precise changes in NK cell lytic function following atrazine exposure have not been fully elucidated. The current study identifies the point at which atrazine exerts its affect on the stepwise process of human NK cell-mediated lyses of the K562 target cell line. Using intracellular staining of human peripheral blood lymphocytes, it was determined that a 24-h in vitro exposure to atrazine did not decrease the level of NK cell lytic proteins granzyme A, granzyme B or perforin. Thus, it was hypothesized that atrazine exposure was inhibiting the ability of the NK cells to bind to the target cell and subsequently inhibit the release of lytic protein from the NK cell. To test this hypothesis, flow cytometry and fluorescent microscopy were employed to analyze NK cell-target cell co-cultures following atrazine exposure. These assays ...
An improved coating for Advanced Gas Cooled Nuclear Reactor austenitic stainless steel fuel cans is described which, tests have shown, inhibits the deposition of carbon on the cans in carbon-containing ionising radiation environments. The coating comprises a refractory oxide which has been prepared by a vapour phase condensation method, in combination with a noble metal. (U.K.).
sFlt-1 (soluble Flt-1) potently inhibits angiogenesis by binding extracellularly to VEGF (vascular endothelial growth factor). In the present paper, we report that hypoxia down-regulates sFlt-1 expression...Full Text Available
Immune challenge induces behavioral changes including reduced ingestion of palatable food. Multiple pathways likely contribute to this effect, including viscerosensory pathways controlling hypothalamic...Full Text Available
IntroductionThe major risk factor for osteoarthritis (OA) is aging, but the mechanisms underlying this risk are only partly understood. Age-related accumulation of advanced glycation...Full Text Available
General corrosion behavior of ALLOY 800 in high temperature water was studied in relation to its surface film structure. The surface film formed in water was found to decrease the corrosion rate of ALLOY 800. This film is composed of Ni ferrite, and can be obtained by oxidation in air or steam. Based on these results, air or steam oxidation treatment to inhibit Ni and Co release of ALLOY 800 into high temperature water is proposed. (author).
General corrosion behavior of ALLOY 800 in high temperature water was studied in relation to its surface film structure. The surface film formed in water was found to decrease the corrosion rate of ALLOY 800. This film is composed of Ni ferrite, and can be obtained by oxidation in air or steam. Based on these results, air or steam oxidation treatment to inhibit Ni and Co release of ALLOY 800 into high temperature water is proposed. (author).
PlGF, one of the ligands for VEGFR-1, has been implicated in tumor angiogenesis. However, more recent studies indicate that genetic or pharmacological inhibition of PlGF signaling does not result in...Full Text Available
Phlorizin is a competitive inhibitor of Na/sup +//glucose symport in animal cells and of H/sup +//3-O-methylglucose (3-O-MeG) symport in liverworts. The effects of this compound on the uptake of (U-/sup 14/C) sucrose and of (/sup 14/C) 3-O-MeG by broadbean (Vicia faba L.) leaf discs were studied. Leaf discs without lower epidermis were preincubated in the dark for 30 min (fresh discs) or for 12 h (aged discs) on a medium buffered at pH 5.0 containing mannitol as an osmoticum. They were then incubated for 30 min in the light on a similar solution added with 1 mM (/sup 14/C) sucrose or (/sup 14/C) 3-O-MeG and 5 mM phlorizin. Phlorizin inhibited uptake of 3-O-MeG by 37 and 50% respectively in fresh and aged discs. Sucrose uptake was more sensitive to the inhibitor than 3-O-MeG uptake and was also more inhibited in aged than in fresh discs (76% inhibition vs 54%). Kinetic studies showed that the inhibition ...
Short term (10 min) influx of 86Rb-labeled potassium into corn (Zea mays L. WF9 × M14) root segments was inhibited by La (NO3)3 or LaCl3....Full Text Available
A synergistic effect exists when benzotriazole (BTAH) and iodide ions are used together to prevent the corrosion of copper in sulfuric acid. The nature of this effect has been studied systematically by using electrochemical techniques and X-ray photoelectron spectroscopy. The synergistic effect is due largely to the formation of a film of Cu(IBTA) complex and is probably polymeric in nature. This new complex film greatly depresses copper dissolution.
Several different approaches exist to generate expressed RNA interference (RNAi) precursors for multiple target inhibition, a strategy referred to as combinatorial (co)RNAi. One such approach makes...Full Text Available
Cordycepin has been shown to interfere with a myriad of molecular processes from RNA elongation to kinase activity, and prevents numerous inflammatory processes in animal models. Here we show in a mouse...Full Text Available
The toxicities of 21 different herbicides to algae (Selenastrum capricornutum and Chlorella vulgaris) and to terrestrial plants (radishes, barley, and bush beans or soybeans) were compared to order to determine the feasibility of using a short-term (96-h) algal growth inhibition test for identifying chemicals having potential toxicity in a 4-week terrestrial plant bioassay. The toxicity of each test chemical, usually in combination with a commercial formulation, was evaluated at six nominal concentrations, between 0 and 100 mg/L growth medium in the algal bioassay or between 0 and 100 mg/kg substate in the terrestrial plant bioassay, in terms of both (1) the no-observed-effect concentration (NOEC), i.e., the highest concentration tested at which no significant (P < 0.05, one-sided test) reduction in algal growth rate or in terrestrial plant yield, relative to controls, was observed; and (2) the concentration at which algal growth rate or terrestrial plant yield ...
The serpin ZPI is a protein Z (PZ)-dependent specific inhibitor of membrane-associated factor Xa (fXa) despite having an unfavorable P1 Tyr. PZ accelerates the inhibition reaction ∼2000-fold...Full Text Available
The metabotropic glutamate receptor 7 (mGluR7) has been reported to be involved in cocaine and alcohol self-administration. However, the role of mGluR7 in relapse to drug seeking is unknown....Full Text Available
A newly synthesized glycine derivative (termed GlyD), 2-(4-(dimethylamino)benzylamino)acetic acid hydrochloride, was used to inhibit uniform and pitting corrosion processes of Al in 0.50 M KSCN solutions (pH 6.8) at 25 "oC. For uniform corrosion inhibition study, Tafel extrapolation, linear polarization resistance and impedance methods were used, complemented with SEM examinations. An independent method of chemical analysis, namely ICP-AES (inductively coupled plasma atomic emission spectrometry) was also used to test validity of corrosion rate measured by Tafel extrapolation method. GlyD inhibited uniform corrosion, even at low concentrations, reaching a value of inhibition efficiency up to 97% at a concentration of 5 x 10"-"3 M. Results obtained from the different corrosion evaluation techniques were in good agreement. This new synthesized glycine derivative was also used to control pit nucleation and ...
The tumor suppressor p53 is often inactivated in breast cancer cells because the overexpression of its repressors (e.g., MDM2 and MDMX). Restoration of p53 activity by small molecules through counteracting...Full Text Available
Ingestion or inhalation of botulinum neurotoxin (BoNT) results in botulism, a severe and frequently fatal disease. Current treatments rely on antitoxins, which while effective cannot reverse...Full Text Available
The ζ chain-associated 70-kDa protein (ZAP-70) of tyrosine kinase plays a critical role in T cell receptor-mediated signal transduction and the immune response. A high level of ZAP-70 expression...Full Text Available
We examined the subcellular localization of ryanodine receptors (RyR) in the cardiac muscle of carp using biochemical, immunohistochemical, and electron microscopic methods and compared it with those of rats and guinea pigs. To achieve this goal, an anti-RyR antibody was newly raised against a synthetic peptide corresponding to an amino acid sequence that was conserved among all sequenced RyRs. Western blot analysis using this antibody detected a single RyR band following the SDS-PAGE of sarcoplasmic reticulum (SR) membranes from carp atrium and ventricle as well as from mammalian hearts and skeletal muscles. The carp heart band had slightly greater mobility than those of mammalian hearts. Although immunohistochemical staining showed evident striations corresponding to the Z lines in longitudinal sections of mammalian hearts, clusters of punctate staining, in contrast, were distributed ubiquitously throughout carp atrium and ventricle. Electron microscopic images ...
In this paper the structural and functional changes of gamma irradiated bovine hemoglobin are presented. Aqueous solutions/1%/of HbO_2 were irradiated in air with doses ranging from 1 to 4 Mrad. Isoelectric focusing indicated change of the charge of irradiated hemoglobin. The isoelectric point of hemoglobin was displaced towards more acid values with increasing doses, up from 1 Mrad. Fingerprint analysis and peptide column chromatography of irradiated hemoglobin demonstrated disturbances increasing with the dose. These changes were confirmed by amino acid analysis which showed that Cys, Met, Trp, His, Pro and Tyr residues were destroyed or modified following irradiation. At doses exceeding 1 Mrad the irradiated solutions of hemoglobin showed a decrease of heme-heme interaction and an increase of affinity for oxygen. Differences observed in oxygen-dissociation curves seem to be correlated with the radiation induced destruction of amino acid residues which are ...
The problem of homochirality is of crucial importance for the origins of Life. While most laboratory studies are focused on the search of physical and chemical sources of handedness in the Universe, they reflect only one aspect of the problem: the origin of homochiral biomolecules. At the same time, any space environments where biomolecules are expected to form and where they have to pass through before the first primitive forms of Life emerge, include strong irradiation or/and high temperatures. This automatically implies the possibility of losing the optical activity, i.e. racemization. The simulation experiments performed by our group deal with the following two aspects of amino acid abiotic chemistry: (1) amino acid pyrolysis associated with their extraterrestrial delivery; and (2) peptide formation from amino acids catalyzed by inorganic oxides. According to our observations, the racemization phenomena are very common in the systems considered, not only under ...
We examined whether or not BMD or bone markers were useful for assessing the risk of vertebral fractures in 248 Japanese men with type 2 diabetes. We analyzed the relationships between bone markers (osteocalcin [OC], bone-specific alkaline phosphatase [BAP], urinary N-terminal cross-linked telopeptide of type-I collagen) or BMD and HbA1c, urinary C-peptide, insulin-like growth factor-I (IGF-I), parathyroid hormone, 1,25(OH)2 vitamin D, and the presence of prevalent vertebral fractures. Multiple regression analysis adjusted for age, body height, weight, duration of diabetes, and serum creatinine showed that serum OC and OC/BAP ratio were correlated negatively with HbA1c (P?P?P?0.05). This association was still significant after additional adjustment for lumbar or femoral neck BMD. Our res...
Aminocyclopropane 1-carboxylic acid (ACC) synthase, a pyridoxal phosphate utilizing enzyme, catalyzes the conversion of S-adenosylmethionine to ACC, the rate limiting step in the biosynthesis of the plant hormone, ethylene. Ethylene, besides being involved in normal plant growth processes, is also produced in response to stress, e.g. wounding, pathogen infection, etc. The authors report the partial purification (400 fold) of ACC synthase from wounded pink tomato pericarp by classical techniques including ammonium sulfate precipitation, ion exchange and phenyl sepharose chromatography. Further purification results in a decrease in specific activity apparently due to the instability of the enzyme and the low levels present in plant tissue. Radiolabeling of a pyridoxal phosphate-utilizing protein in the ACC synthase enriched fraction was achieved. Evidence that this radiolabeled protein is ACC synthase will be presented. Amino acid sequence determination of putative ACC synthase-derived ...
We describe a method for the analysis of multi-site phosphorylation in serine/threonine (Ser/Thr)-rich protein sequences. Site-specific mutagenesis was used to introduce tryptic cleavage sites in the serine glutamine/threonine glutamine cluster domain (SCD) of the human checkpoint protein kinase (Chk2). The mutant proteins were shown to autophosphorylate on residues that are inducibly phosphorylated when mammalian cells are exposed to ionizing radiation (serine 33/35, serine 516, threonine 68 and threonine 432). Five Ser/Thr clusters within the SCD were flanked by arginine or lysine residues to produce tryptic peptides for nanospray liquid chromatography (nanoLC)/linear quadrupole ion trap Fourier transform ion cyclotron resonance mass spectrometry. Phosphorylation sites were assigned usin...
The structural organization of the genes encoding Bungarus multicinctus protease inhibitor-like proteins (PILPs), PILP-1, PILP-2 and PILP-3, are reported in this study. Unlike PILP-2 and PILP-3, recombinant PILP-1 exhibited inhibitory activity on trypsin. PILP genes and B chain genes shared identical organization with three exons interrupted by two introns in similar positions. On the contrary, intron 1 of these genes had a similar size, a notable variation with the size of intron 2 was observed. It was found that two regions at the second intron of B1 chain and B2 chain genes were absent in that of PILP genes. Noticeably, intronic insertion in the second intron of B chain genes appeared in the promoter region of PILP-1 gene, but not in that of PILP-2 and PILP-3 genes. Comparative analyses of PILP genes and B chain genes showed that the protein-coding regions of the exons are more diverse than introns, except for in the signal peptide domain. These results suggest ...
A radioimmunoassay is described for the molluscan neuropeptide, Phe-Met-Arg-Phe-NH"2(FMRFamide). The antibody used is C-terminal-specific and shows slight but significant (1-2%) cross-reactivity with chicken pancreatic polypeptide (APP). The assay has been used to identify in rat brain extracts a pair of molecules that may represent mammalian counterparts of FMRFamide. Their concentrations were highest in spinal cord and hypothalamus (>10 pmol.g"-_1) and lowest in cerebellum and striatum (<3.5 pmol.g"-_1). The two immunoreactive peptides were separated on CM ion-exchange chromatography where they appeared to be less basic than FMRFamide. On Sephadex G50 gel filtration one eluted in a similar position to FMRFamide and the other slightly earlier suggesting it may be of higher molecular weight. The rat immunoreactive components do not correspond to previously described neuropeptides or hormones, and may be members of a new group of mammalian neuropeptides with ...
Light increased the rate of LHCP synthesis as measured by pulse-labeling with /sup 35/SO/sub 4/ and immunoprecipitation with antibody specific for Euglena LHCP. In addition to the mature LHCP, 26,000 daltons, the LHCP specific antibody immunoprecipitated large amounts of several proteins having molecular weights of approximately 100,000. On immunoblots of immunoprecipitated unlabeled protein, the antibody only detected the mature LHCP suggesting that the high molecular weight proteins are not LHCP aggregates produced during immunoprecipitation. After a 10 min pulse with /sup 35/SO/sub 4/, the 100,000 dalton proteins constituted over 80% of the immunoprecipitated material. In a subsequent chase, the radioactivity in the 100,000 dalton proteins decreased and the radioactivity in the mature LHCP increased suggesting a precursor-product relationship. After a 35 minute chase, the mature LHCP was the major radioactive protein immunoprecipitated. Peptide mapping and in ...
Selecting an appropriate matrix solution is one of the most effective means of increasing the ionization efficiency of phosphopeptides in matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). In this study, we systematically assessed matrix combinations of 2, 6-dihydroxyacetophenone (DHAP) and diammonium hydrogen citrate (DAHC), and demonstrated that the low ratio DHAP/DAHC matrix was more effective in enhancing the ionization of phosphopeptides. Low femtomole level of phosphopeptides from the tryptic digests of ?-casein and ?-casein was readily detected by MALDI-TOF-MS in both positive and negative ion mode without desalination or phosphopeptide enrichment. Compared with the DHB/PA matrix, the optimized DHAP/DAHC matrix yielded superior sample homogeneity and higher phosphopeptide measurement sensitivity, particularly when multiple phosphorylated peptides were assessed. Finally, the DHAP/DAHC matrix was applied to identify ...
The heavy chains of Acanthamoeba myosins, IA, IB and II, turkey gizzard myosin, and rabbit skeletal muscle myosin subfragment-1 were specifically labeled by radioactive ATP, ADP, and UTP, each of which is a substrate or product of myosin ATPase activity, when irradiated with uv light at 0"0C. With UTP, as much as 0.45 mol/mol of Acanthamoeba myosin IA heavy chain and 1 mol/mol of turkey gizzard myosin heavy chain was incorporated. Evidence that the ligands were associated with the catalytic site included the observations that reaction occurred only with nucleotides that are substrates or products of the ATPase activity; that the reaction was blocked by pyrophosphate which is an inhibitor of the ATPase activity; that ATP was bound as ADP; and that label was probably restricted to a single peptide following limited subtilisin proteolysis of labeled Acanthamoeba myosin IA heavy chain and extensive cleavage with CNBr and trypsin of labeled turkey gizzard myosin heavy ...
We performed density functional calculations to examine the effects of solvation, hydrogen bonding, backbone conformation, and the side chain on 15N chemical shielding in proteins. We used N-methylacetamide (NMA) and N-formyl-alanyl-X (with X being one of the 19 naturally occurring amino acids excluding proline) as model systems. In addition, calculations were performed for selected fragments from protein GB3. The conducting polarizable continuum model was employed to include the effect of solvent in the density functional calculations. Our calculations for NMA show that the augmentation of the polarizable continuum model with the explicit water molecules in the first solvation shell has a significant influence on isotropic 15N chemical shift but not as much on the chemical shift anisotropy. The difference in the isotropic chemical shift between the standard ?-sheet and ?-helical conformations ranges from 0.8 to 6.2 ppm depending on the residue type, with the mean of 2.7 ppm. This is ...
The study of chemoattractant receptors on human monocytes had been limited by the lack of a radioligand suitable for use with the small numbers of cells routinely available from human donors. A new synthetic oligopeptide radioligand f(/sup 35/S)Met-leu-phe, with a higher specific radioactivity than was available with the tritiated compound, was used to characterize a chemoattractant receptor on freshly isolated human blood monocytes. These cells bind f(/sup 35/)met-leu-phe with a dissociation constant (KD) of 30.2 +/- 5.6 nM and contain 84,000 +/- 11,300 receptors per cell. f(/sup 35/)met-leu-phe does not bind specifically to blood lymphocytes. The specificity of the oligopeptide receptor on monocytes is indistinguishable from the oligopeptide chemoattractant receptor on human polymorphonuclear leukocytes. Using f(/sup 35/)met-leu-phe, it will now be feasible to study the chemotactic peptide receptor on small numbers of partially purified peripheral blood monocytes ...
The production of molecularly imprinted polymers (MIPs) for the recognition of C-terminal cholecystokinin pentapeptide (CCK-5) in the presence of metal ion is reported. The MIPs were produced under the same molar ratio of template to monomers (acrylamide, N,N'-methylene bisacrylamide) in the presence or absence of nitrilotriacetic acid-nickel (Ni-NTA) complex. Scanning electron microscopy images of MIPs were obtained in an attempt to correlate the adsorption characteristics with polymer's morphology. Subsequently Ni2+ was removed and substituted by other divalent ions such as Mg2+, Fe2+, Zn2+, Co2+ and Cu2+. It was found that polymers containing the metal ion complex with the order Fe-NTA, Ni-NTA and Cu-NTA presented lower dissociation constant values than the rest thus exhibiting stronger guest binding activity. The percentage of theoretical maximum binding sites Bmax was almost the same for these ions, indicating that the ion-template coordination is responsible only for their ...
The ability to feed on vertebrate blood has evolved many times in various arthropod clades. Each time this trait evolves, novel solutions to the problem posed by vertebrate hemostasis are generated. Consequently, saliva of blood-feeding arthropods has proven to be a rich source of antihemostatic molecules. Vasodilators include nitrophorins (nitric oxide storage and transport heme proteins), a variety of peptides that mimic endogenous vasodilatory neuropeptides, and proteins that catabolize or sequester endogenous vasoconstrictors. A variety of platelet aggregation inhibitors antagonize platelet responses to wound-generated signals, including ADP, thrombin, and collagen. Anticoagulants disrupt elements of both the intrinsic and extrinsic pathways. Molecular approaches (termed 'sialomics') to characterize the full inventory of mRNAs transcribed in salivary glands have revealed a surprising level of complexity within a single species. Multiple salivary proteins may be ...
Summary Background Treatment of localised renal cell carcinoma consists of partial or radical nephrectomy. A substantial proportion of patients are at risk for recurrence because no effective adjuvant therapy exists. We investigated the use of an autologous, tumour-derived heat-shock protein (glycoprotein 96)-peptide complex (HSPPC-96; vitespen) as adjuvant treatment in patients at high risk of recurrence after resection of locally advanced renal cell carcinoma. Methods In this open-label trial, patients were randomly assigned to receive either vitespen (n=409) or observation alone (n=409) after nephrectomy. Randomisation was done in a one to one ratio by a computer-generated pseudo-random number generator, with a block size of four, and was stratified by performance score, lymph node stat...
Orientational constraints obtained from solid state NMR experiments on anisotropic samples are used here in molecular dynamics (MD) simulations for determining the structure and dynamics of several different membrane-bound molecules. The new MD technique is based on the inclusion of orientation dependent pseudo-forces in the COSMOS-NMR force field. These forces drive molecular rotations and re-orientations in the simulation, such that the motional time-averages of the tensorial NMR properties approach the experimentally measured parameters. The orientational-constraint-driven MD simulations are universally applicable to all NMR interaction tensors, such as chemical shifts, dipolar couplings and quadrupolar interactions. The strategy does not depend on the initial choice of coordinates, and is in principle suitable for any flexible molecule. To test the method on three systems of increasing complexity, we used as constraints some deuterium quadrupolar couplings from the literature on ...
Orientational constraints obtained from solid state NMR experiments on anisotropic samples are used here in molecular dynamics (MD) simulations for determining the structure and dynamics of several different membrane-bound molecules. The new MD technique is based on the inclusion of orientation dependent pseudo-forces in the COSMOS-NMR force field. These forces drive molecular rotations and re-orientations in the simulation, such that the motional time-averages of the tensorial NMR properties approach the experimentally measured parameters. The orientational-constraint-driven MD simulations are universally applicable to all NMR interaction tensors, such as chemical shifts, dipolar couplings and quadrupolar interactions. The strategy does not depend on the initial choice of coordinates, and is in principle suitable for any flexible molecule. To test the method on three systems of increasing complexity, we used as constraints some deuterium quadrupolar couplings from the literature on ...
Orientational constraints obtained from solid state NMR experiments on anisotropic samples are used here in molecular dynamics (MD) simulations for determining the structure and dynamics of several different membrane-bound molecules. The new MD technique is based on the inclusion of orientation dependent pseudo-forces in the COSMOS-NMR force field. These forces drive molecular rotations and re-orientations in the simulation, such that the motional time-averages of the tensorial NMR properties approach the experimentally measured parameters. The orientational-constraint-driven MD simulations are universally applicable to all NMR interaction tensors, such as chemical shifts, dipolar couplings and quadrupolar interactions. The strategy does not depend on the initial choice of coordinates, and is in principle suitable for any flexible molecule. To test the method on three systems of increasing complexity, we used as constraints some deuterium quadrupolar couplings from the literature on ...
Snake envenomation employs three well integrated strategies: prey immobilization via hypotension, prey immobilization via paralysis, and prey digestion. Purines (adenosine, guanosine and inosine) evidently play a central role in the envenomation strategies of most advanced snakes. Purines constitute the perfect multifunctional toxins, participating simultaneously in all three envenomation strategies. Because they are endogenous regulatory compounds in all vertebrates, it is impossible for any prey organism to develop resistance to them. Purine generation from endogenous precursors in the prey explains the presence of many hitherto unexplained enzyme activities in snake venoms: 5'-nucleotidase, endonucleases (including ribonuclease), phosphodiesterase, ATPase, ADPase, phosphomonoesterase, and NADase. Phospholipases A(2), cytotoxins, myotoxins, and heparinase also participate in purine liberation, in addition to their better known functions. Adenosine contributes to prey immobilization ...
Poncirin, flavanone glycoside, isolated from the fruit of Poncirus trifoliata, has anti-bacterial and anti-inflammatory activities. In this study, the effects of poncirin on the differentiation of mesenchymal stem cells were investigated. The C3H10T1/2 mesenchymal stem cells and primary bone marrow mesenchymal stem cells were studied. In the C3H10T1/2 cells, poncirin prevented adipocyte differentiation, as demonstrated by inhibition of cytoplasm lipid droplet accumulation and peroxisome proliferator-activating receptor-? (PPAR-?) and CCAAT-enhancer-binding protein-? (C/EBP-?) mRNA expression. By contrast, poncirin enhanced the expression of the key osteogenic transcription factors, runt-related transcription factor 2 (Runx2) and transcriptional coactivator with PDZ-binding motif (TAZ). Poncirin also enhanced expression of the osteogenic marker genes including alkaline phosphatase (ALP) and osteocalcin (OC). Poncirin increased mineral nodule formation in primary ...
NFAT involvement in adipocyte physiological processes was examined by treatment with CsA and/or GSK3{beta} inhibitors (Li{sup +} or TZDZ-8), which prevent or increase NFAT nuclear translocation, respectively. CsA treatment reduced basal and TNF{alpha}-induced rates of lipolysis by 50%. Adipocytes preincubated with Li{sup +} or TZDZ-8 prior to CsA and/or TNF{alpha}, exhibited enhanced basal rates of lipolysis and complete inhibition of CsA-mediated decreased rates of lipolysis. CsA treatment dramatically reduced the mRNA levels of adipocyte-specific genes (aP2, HSL, PPAR{gamma}, ACS and Adn), compared with control or TNF{alpha}-treatment, whereas Li{sup +} pretreatment blocked the inhibitory effects of CsA, and mRNA levels of aP2, HSL, PPAR{gamma}, and ACS were found at or above control levels. NFAT nuclear localization, assessed by EMSA, confirmed that CsA or Li{sup +} treatments inhibited or increased NFAT nuclear translocation, respectively. ...
Tau is a microtubule-associated protein that promotes microtubule assembly and stability. In Alzheimer's disease and related tauopathies, tau fibrillizes and aggregates into neurofibrillary tangles. Recently, oleocanthal isolated from extra virgin olive oil was found to display non-steroidal anti-inflammatory activity similar to ibuprofen. Since our unpublished data indicates an inhibitory effect of oleocanthal on A? fibrillization, we reasoned that it might inhibit tau fibrillization as well. Herein we demonstrate that oleocanthal abrogates fibrillization of tau by locking tau into the naturally unfolded state. Using PHF6 consisting of the amino acid residues VQIVYK, a hexapeptide within the third repeat of tau that is essential for fibrillization, we show that oleocanthal forms an adduct with the lysine via initial Schiff base formation. Structure and function studies demonstrate that the two aldehyde groups of oleocanthal are required for the inhibitory ...