An /alpha//sub 2/-adrenergic receptor subtype has been cloned from a human kidney cDNA library using the gene for the human platelet /alpha//sub 2/-adrenergic receptor as a probe. The deduced amino acid sequence resembles the human platelet /alpha//sub 2/-adrenergic receptor and is consistent with the structure of other members of he family of guanine nucleotide-binding protein-coupled receptors. The cDNA was expressed in a mammalian cell line (COS-7), and the /alpha//sub 2/-adrenergic ligand (/sup 3/H)rauwolscine was bound. Competition curve analysis with a variety of adrenergic ligands suggests that this cDNA clone represents the /alpha//sub 2/B-adrenergic receptor. The gene for this receptor is on human chromosome 4, whereas the gene for the human platelet ...
Reproductive aging in males is characterized by a diminution in sexual behavior beginning in middle age. We investigated the relationships among testosterone, androgen receptor (AR) and estrogen...Full Text Available
Since a large body of data has suggested a significant role for alpha-fetoprotein (AFP) in the regulation of the immune response at a number of levels, we examined the possibility of a specific receptor...Full Text Available
Several investigations suggested abnormalities in circadian rhythms are related to the pathophysiology of psychiatric disorders, including drug addiction. Recently, orphan nuclear receptor rev-erb alpha...Full Text Available
BackgroundEstrogen receptorsalpha (ERα) and beta (ERβ) are transcription factors (TFs) that mediate estrogen signaling and define the hormone-responsive phenotype...Full Text Available
The expression status of the estrogen receptoralpha (ERα) and that of the epidermal growth factor receptor Her-2/neu frequently correlate inversely in breast cancers. While ERα-dependent...Full Text Available
1. The stereospecificity of the enantiomers of LY253352, a potent and selective alpha 1-adrenoceptor antagonist, were studied in the human prostate and canine brain using radioligand receptor binding...Full Text Available
Although peroxisome proliferator-activated receptoralpha (PPARα) is closely associated with myocardial fatty acid metabolism, the pathophysiological role of PPARα in myocardial infarction...Full Text Available
..cap alpha..-2 adrenergic agents have been shown to influence blood pressure, heart rate and other physiological and behavioral functions through interactions with adrenergic pathways within the central nervous system. Pharmacologically relevant ..cap alpha..-1 adrenergic receptors were biochemically characterized and radiohistochemically analyzed in intact tissue sections of the rat and human central nervous system. The anatomical distribution of the ..cap alpha..-2 receptors, labeled with the agonist (/sup 3/H)para-aminoclonidine, verified the concept that ..cap alpha..-2 receptors are closely associated with adrenergic nerve terminals and that ..cap alpha..-2 agents can influence autonomic and endocrine function through an action in the central nervous system. Since ..cap alpha..-2 agonists can ...
[3,5-"3H] 4-Azidoclonidine 6 was prepared from [3,5-"3H] 4-aminoclonidine 4 and has emerged as a valuable tool to study the alpha-2-adrenergic receptor. (author)
Prenatal cocaine exposure produces sustained neurobehavioral and brain synaptic changes closely resembling those of animals with defective alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic...Full Text Available
A parallel bundle of transmembrane (TM) alpha-helices surrounding a central pore is present in several classes of ion channel, including the nicotinic acetylcholine receptor (nAChR). We have modeled...Full Text Available
The majority of diseases in the retina are caused by genetic mutations affecting the development and function of photoreceptor cells. The transcriptional networks directing these processes are regulated...Full Text Available
The immunolocalization of the low density lipoprotein receptor-related protein 1 (LRP1) and its ligand alpha 2-Macroglobulin (α2M) was examined in tissues from human donor...Full Text Available
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 neuronal nicotinic acetylcholine receptor {alpha}7 subunit is a member of a family of ligand-gated ion channels, and is the only subunit know to bind {alpha}-bungarotoxin in mammalian brain. {alpha}-Bungarotoxin binding sites are known to be more abundant in the hippocampus of mouse strains that are particularly sensitive to nicotine-induced seizures. The {alpha}7 receptor is highly permeable to calcium, which could suggest a role in synaptic plasticity in the nervous system. Auditory gating deficiency, an abnormal response to a second auditory stimulus, is characteristic of schizophrenia. Mouse strains that exhibit a similar gating deficit have reduced hippocampal expression of the {alpha}7 subunit. We have cloned and sequenced the full length cDNA for the mouse {alpha}7 gene (Acra-7) and characterized its gene ...
The functional interaction between the peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) and its coactivator PGC-1{alpha} is crucial for the normal physiology of PPAR{gamma} and its pharmacological response to antidiabetic treatment with rosiglitazone. Here we report the crystal structure of the PPAR{gamma} ligand-binding domain bound to rosiglitazone and to a large PGC-1{alpha} fragment that contains two LXXLL-related motifs. The structure reveals critical contacts mediated through the first LXXLL motif of PGC-1{alpha} and the PPAR{gamma} coactivator binding site. Through a combination of biochemical and structural studies, we demonstrate that the first LXXLL motif is the most potent among all nuclear receptor coactivator motifs tested, and only this motif of the two LXXLL-related motifs in PGC-1{alpha} is capable of binding to PPAR{gamma}. Our ...
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.
We report the isolation of cDNA clones for the mouse {alpha}7 neuronal nicotinic acetylcholine receptor subunit (gene symbol Acra7), the only nicotinic receptor subunit known to bind a-bungarotoxin in mammalian brain. This gene may have relevance to nicotine sensitivity and to some electrophysiologic findings in schizophrenia. The mouse {alpha}7 subunit gene encodes a protein of 502 amino acids with substantial identity to the rat (99.6%), human (92.8%), and chicken (87.5%) amino acid sequences. The {alpha}7 gene was mapped to mouse chromosome 7 near the p locus with the following gene order from proximal to distal: Myod1-3.5 {+-}1.7 cM-Gas2-0.9 cM {+-} 0.9 cM-D7Mit70-1.8 {+-} 1.2 cM- Acra7-4.4 {+-}1.0 cM-Hras1-ps11/Igf1r/Snrp2a. The human gene was confirmed to map to the homologous region of human chromosome 15q13-q14. 26 refs., 3 figs.
The recently described retinoid X receptors (RXRs) respond to the novel retinoid 9-cis-retinoic acid and also serve as heterodimeric partners for the vitamin D, thyroid hormone, and retinoic acid receptors (VDR, TR, and RAR, respectively). In this work, the authors report high-resolution localization of the human RXR genes within cytogenetic bands and also within a standard reference map of cosmid DNA markers on human chromosomes. They have determined the location of the human RXR genes by pairwise hybridization of the RXR cosmids and reference markers, using fluorescence in situ hybridization. They localized (i) RXR[alpha] (RXRA) to chromosome 9 band q34.3; (ii) RXR[beta] (RXRB) to chromosome 6 band 21.3; and (iii) RXR[gamma] (RXRG) to chromosome 1 band q22-q23. Six retinoid-responsive transcription factors have been identified so far, including three retinoic acid receptors in addition to the three ...
A promising drug target currently under investigation to improve cognitive deficits in neuropsychiatric and neurological disorders is the neuronal nicotinic alpha7 acetylcholine receptor (a7nAChR). Improving cognitive impairments in diseases such as Alzheimer's (AD) and schizophrenia remains a large unmet medical need, and the a7nAChR has many properties that make it an attractive therapeutic target. The a7nAChR is a ligand gated ion channel that has particularly high permeability to Ca^2^+ and is expressed in key brain regions involved in cognitive processes (e.g., hippocampus). The a7nAChRs are localized both pre-synaptically, where they can regulate neurotransmitter release, and post-synaptically where they can activate intracellular signaling cascades and influence downstream processes...
[alpha]-Melanocyte stimulating hormone ([alpha]-MSH), a hormone originally named for its ability to regulate pigmentation of melanocytes, is a 13-amino-acid post-translational product of the pro-opiomelanocortin (POMC) gene. [alpha]-MSH and the other products of POMC processing, which share the core heptapeptide amino acid sequence Met-Glu (Gly)-His-Phe-Arg-Trp-Gly (Asp), the adrenocorticotropic hormone (ACTH), [beta]-MSH, and [gamma]-MSH, are collectively referred to as melanocortins. While best known for their effects on the melanocyte (pigmentation) and adrenal cortical cells (steroidogenesis), melanocortins have been postulated to function in diverse activities, including enhancement of learning and memory, control of the cardiovascular system, analgesia, thermoregulation, immunomodulation, parturition, and neurotrophism. To identify the chromosomal band encoding the human melanocortin-1 receptor ...
Radioiodinated ..cap alpha..-bungarotoxin, the venom of Bungarus multicinctus, is commonly used for the detection and quantification of nicotinic acetylcholine receptors (nAChR) and anti-nAChR antibodies. A radioiodination method is described which is simple and yields a fully active product which, after fractionation, has a specific activity tenfold higher (900 Ci/mmol) than those routinely used, resulting in enhanced sensitivity of assays and conservation of material, especially muscle extracts.
To investigate mechanisms responsible for positive and negative transcriptional control, the authors have utilized two types of promoters that are diffferentially regulated by thyroid hormone (T{sub 3}) receptors. Promoters containing the palindromic T{sub 3} response element TCAGGTCA TGACCTGA are positively regulated by the T{sub 3} receptor after the administration of T{sub 3}, whereas otherwise identical promoters containing the estrogen response element TCAGGTCA CTG TGACCTGA can be regulated negatively; converse effects are observed with the estrogen receptor. They describe evidence that the transcriptional inhibitory effects of the T{sub 3} or estrogen receptors on the estrogen or T{sub 3} response elements, respectively, are imposed by amino acid sequences in the C'-terminal region that colocalize with dimerization and hormone-binding domains and that these sequences can transfer ...
(3H)Cyclofoxy (CF: 17-cyclopropylmethyl-3,14-dihydroxy-4,5-alpha-epoxy-6-beta-fluoromorp hinan) is an opioid antagonist with affinity to both mu and kappa subtypes that was synthesized for quantitative evaluation of opioid receptor binding in vivo. Two sets of experiments in rats were analyzed. The first involved determining the metabolite-corrected blood concentration and tissue distribution of CF in brain 1 to 60 min after i.v. bolus injection. The second involved measuring brain washout for 15 to 120 s following intracarotid artery injection of CF. A physiologically based model and a classical compartmental pharmacokinetic model were compared. The models included different assumptions for transport across the blood-brain barrier (BBB); estimates of nonspecific tissue binding and specific binding to a single opiate receptor site were found to be essentially the same with both models. The nonspecific binding equilibrium ...
1 Measurements of the binding of 12-alpha-[3H]-digoxin to the membranes of intact erythrocytes, erythrocytic 86rubidium uptake and intraerythrocytic sodium concentrations have been made in the red cells...Full Text Available
The pharmacology of the alpha-2 adrenoceptor of the human adipocyte was improved by using some new alpha-2 antagonists from different chemical families (imidazolines, benzazepines and benzofuroquinolizines) in biological and binding assays. Moreover, investigations were also carried out to define the binding properties of a new imidazolinic antagonist, RX821002 (2-(2-methoxy-1,4-benzodioxan-2yl)-2-imidazoline), which could be a potential radioligand. (3H)RX821002 binding was very rapid and reversible. Saturation isotherms indicated that (3H)RX821002 labeled, with high affinity, a homogeneous population of noninteracting binding sites with a mean Kd of 0.98 +/- 0.05 nM (n = 6). The binding of (3H)RX821002 on the human fat cell alpha-2 adrenoceptor displayed a specificity which is strictly similar to that obtained with (3H)rauwolscine and which is classical for an alpha-2 A adrenoceptor. The binding ...
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.
Previous studies from this laboratory have shown that certain N-substituted phthalimides (NSPs) exhibit GA-like activity in a range of specific bioassays and that bioactive NSPs compete with ({sup 3}H)-GA{sub 4} for soluble binding sites in cucumber homogenates. As such, these compounds may prove useful in the purification and characterization of GA receptor proteins. To this end, five azido-NSPs have been synthesized and are currently being screened for biological activity and photochemical stability. Three azido-NSPs elicit {alpha}-amylase production in barley half-seeds and stimulate tissue elongation in d{sub 5} maize, lettuce, sunflower, and soybean. Further evaluations are in progress and these data as well as the utility of these compounds as photo-affinity ligands will be discussed.
1 Candoxin (MW 7334.6), a novel toxin isolated from the venom of the Malayan krait Bungarus candidus, belongs to the poorly characterized subfamily of nonconventional three-finger toxins present in Elapid venoms. The current study details the pharmacological effects of candoxin at the neuromuscular junction. 2 Candoxin produces a novel pattern of neuromuscular blockade in isolated nerve-muscle preparations and the tibialis anterior muscle of anaesthetized rats. In contrast to the virtually irreversible postsynaptic neuromuscular blockade produced by curaremimetic alpha-neurotoxins, the neuromuscular blockade produced by candoxin was rapidly and completely reversed by washing or by the addition of the anticholinesterase neostigmine. 3 Candoxin also produced significant train-of-four fade during the onset of and recovery from neuromuscular blockade, both, in vitro and in vivo. The fade phenomenon has been attributed to a blockade of putative presynaptic nicotinic ...
The purpose of this study was to examine arachidonic acid (AA) metabolism and to characterize the type of adrenergic receptor (AR) involved in the production of the major metabolite of this fatty acid. ({sup 14}C)AA was incubated with GPT-rings and the radiolabelled products were extracted and separated by TLC method. The medium was also assayed for radiolabelled immunoreactive PG's (iPG's) and leukotrienes (LT) B4 and C4 by RIA or Enzyme immunoassay (EIA) after exposure to various AR agonists. ({sup 14}C)AA was incorporated into GPT-rings and metabolized mainly into iPGE2 and smaller amounts into PGF2{alpha}. Trace amounts of PGD2 and 6-keto-PGF1{alpha} but not LTB4 or LTC4 were detected by RIA and/or EIA. Incubation of GPT rings for 15 minutes with isoproterenol and salbutamol resulted in a significant increase of PGE2 synthesis (optimum conc: 10{sup {minus}7}, 10{sup {minus}7}M respectively). In ...
The purpose of this study was to examine arachidonic acid (AA) metabolism and to characterize the type of adrenergic receptor (AR) involved in the production of the major metabolite of this fatty acid. ["1"4C]AA was incubated with GPT-rings and the radiolabelled products were extracted and separated by TLC method. The medium was also assayed for radiolabelled immunoreactive PG's (iPG's) and leukotrienes (LT) B4 and C4 by RIA or Enzyme immunoassay (EIA) after exposure to various AR agonists. ["1"4C]AA was incorporated into GPT-rings and metabolized mainly into iPGE2 and smaller amounts into PGF2#alpha#. Trace amounts of PGD2 and 6-keto-PGF1#alpha# but not LTB4 or LTC4 were detected by RIA and/or EIA. Incubation of GPT rings for 15 minutes with isoproterenol and salbutamol resulted in a significant increase of PGE2 synthesis (optimum conc: 10"-"7, 10"-"7M respectively). In contrast, dobutamine, norepinephrine, phenylnephrine ...
The widespread use of tobacco and alcohol among adolescents might be related to the ability of nicotine and ethanol to facilitate social interactions. To investigate the neurobehavioral mechanisms underlying the prosocial effects of nicotine and ethanol, we focused on social play behavior, the most characteristic social activity in adolescent rats. Social play behavior is rewarding, and it is modulated through opioid, cannabinoid and dopaminergic neurotransmission, which are also involved in the reinforcing properties of nicotine and ethanol. We found that nicotine and ethanol increased social play, without affecting locomotion or social exploration. Their effects depended on the level of social activity of the partner, and were comparable in familiar and unfamiliar environments. At doses that increased social play, nicotine and ethanol had no anxiolytic effects in the elevated plus-maze. By contrast, the prototypical anxiolytic drug diazepam reduced social play at doses that reduced ...
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 ...
The receptor-associated protein (RAP) is a molecular chaperone that binds tightly to certain newly synthesized LDL receptor family members in the endoplasmic reticulum (ER) and facilitates their delivery...Full Text Available
Structural analysis of an acetylcholine receptor from Torpedo californica leads to a three-dimensional model in which a "monomeric" receptor is shown to contain subunits arranged around a central ionophoretic...Full Text Available
Orphan G protein-coupled receptors (GPCRs) are receptors lacking endogenous ligands. Found by molecular biological analyses, they became the roots of reverse pharmacology, in which receptors are attempted...Full Text Available
Many microbial pathogens recognize oligosaccharides displayed on the surface of host cells as receptors for toxins and adhesins. These ligand-receptor interactions are critical for disease pathogenesis,...Full Text Available
AMPA receptors (AMPARs) are critical for synaptic plasticity, and are subject to alterations based on subunit composition and receptor trafficking to and from the plasma membrane. One of the...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
Hormone potency depends on receptor availability, regulated via gene expression and receptor trafficking. To ascertain how central leptin receptors are regulated, the effects of leptin challenge, high-fat...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
To study the effect of agonist on the TRH (thyrotrophin-releasing hormone) receptor protein, an epitope-tagged receptor was stably expressed in HEK-293 cells (human embryonic kidney 293 cells) and receptor...Full Text Available
We studied the effect of extracellular Ca"2"+ concentration ([Ca"2"+]_e) on adipocyte differentiation. Preadipocytes exposed to continuous [Ca"2"+]_e higher than 2.5 mmol/l accumulated little or no cytoplasmic lipid compared to controls in 1.8 mmol/l [Ca"2"+]_e. Differentiation was monitored by Oil Red O staining of cytoplasmic lipid and triglyceride assay of accumulated lipid, by RT-PCR analysis of adipogenic markers, and by the activity of glycerol-3-phosphate dehydrogenase (GPDH). Elevated [Ca"2"+]_e inhibited expression of peroxisome proliferator-activated receptor #gamma#, CCAAT/enhancer binding protein #alpha#, and steroid regulatory binding element protein. High [Ca"2"+]_e significantly inhibited differentiation marker expression including adipocyte fatty acid binding protein, and GPDH. The decrease in Pref-1 expression that accompanied differentiation also was prevented by high [Ca"2"+]_e. Treatment of 3T3-L1 cells with high [Ca"2"+]_e ...
The retinoic acid receptor-related orphan receptors α and γ (RORα (NR1F1) and RORγ (NR1F3)) are orphan nuclear receptors and perform critical roles in regulation of development,...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.
The Zollinger-Ellison syndrome (ZES) is taken as an example of the diagnostic and therapeutic strategy in gastro-entero-pancreatic endocrine tumours, given the standard characteristics of this procedure, whatever the nature of the primitive tumour. Management of ZES includes: anatomical localization of gastrinoma and of possible metastases, in 60 % of cases this step conditioning therapeutic indications and chances of cure; search of a type 1-multiple endocrine neoplasia (MEN A), in 25 % of cases; therapeutic indications: ablative surgery with curative intent in case of gastrinoma and of resectable liver metastases, palliative treatment otherwise: anti-secretory drugs, somatostatin analogues, chemotherapy and interferon {alpha}; long-term follow-up of patients with resected tumour. At each step, somatostatin receptor scintigraphy with indium 111-pentetreotide does play a pivotal role. (author). 110 refs.
Objective: To study the effects of minocycline hydrochloride (MINO) on the formation of tartrate-resistant acid phosphatase (TRAP) staining-positive multinucleated osteoclast-like cells in mouse bone marrow cells (BMCs) treated with 1@a,25(OH)"2D"3 or soluble receptor activator of nuclear factor-@kB ligand (s-RANKL). Materials and methods: Mouse BMCs were cultured in alpha-modified minimum essential medium containing foetal calf serum (10%) and tetracyclines (2.5, 5 and 10@mM), such as MINO, tetracycline hydrochloride (TC), oxytetracycline hydrochloride (OXT) or doxycycline (DOXY) in the presence of 1@a,25(OH)"2D"3 (10nM) or s-RANKL (20ng/ml) for 7 days, and the number of TRAP staining-positive osteoclast-like cells was counted. In RNA isolated from BMCs treated with 1@a,25(OH)"2D"3 or s-R...
Unfamiliar male meadow voles induce pregnancy disruptions when they are in physical contact with females, but the presence of the female's original mate partially protects her from the blocking effects of an unfamiliar male. This research examines how behavioral interactions affect pregnancy disruptions by testing two hypotheses: a) original males protect females by reducing the aggressive interactions between females and strange males; and b) administration of clonidine, an alpha 2-adrenergic receptor agonist that decreases activity, aggression, and sexual motivation, will decrease the pregnancy-blocking ability of strange males. Strange males were more aggressive when the original sire was absent, indicating that this change in behavior may be related to their greater success in disrupting pregnancy. When injected with clonidine, males were less likely to block pregnancy, and they showed less contact and mating behavior than when they ...
The authors have used limited proteolysis of affinity-labeled estrogen receptors (ER), coupled with antireceptor antibody immunoreactivity, to assess structural features of ER and the relatedness of ER from MCF-7 human breast cancer and rat uterine cells. MCF-7 ER preparations covalently labeled with ["3H]tamoxifen aziridine (["3H]TAZ) were treated with trypsin (T), #alpha#-chymotrypsin (C), or Staphylococcus aureus V8 protease prior to electrophoresis on sodium dodecyl sulfate gels. Fluorography revealed a distinctive ladder of ER fragments containing TAZ for each protease generated from the M/sub r/ 66,000 ER. Immunoblot detection with the primate-specific antibody D75P3#gamma# revealed that all immunoreactive fragments corresponded to TAZ-labeled fragments but that some small TAZ-labeled fragments were no longer immunoreactive. In contrast, use of the antibody H222SP#gamma# revealed a correspondence between TAZ-labeled and immunoreactive ...
Hepatocellular carcinoma (HCC) is the most common primary liver cancer and has very limited therapeutic options. Recently, it has been found that hyaluronic acid (HA) shows selective binding to CD44 receptors expressed in most cancer histotypes. Since the trend in cancer treatment is the use of targeted radionuclide therapy, the aim of this research was to label HA with rhenium-188 and to evaluate its potential use as a hepatocarcinoma therapeutic radiopharmaceutical. Methods: {sup 188}Re-HA was prepared by a direct labelling method to produce a ReO(O-COO){sub 2}-type coordination complex. {sup 188}Re-HA protein binding and its stability in saline, phosphate buffer, human serum and cysteine solutions were determined. Biokinetic and dosimetric data were estimated in healthy mice (n=60) using the Medical Internal Radiation Dose methodology and mouse model beta-absorbed fractions. To evaluate liver toxicity, alanine aminotranferase (AST) and aspartate aminotranferase ...
BackgroundThe pregnane X receptor (PXR; NR1I2), a member of the nuclear receptor superfamily, regulates the expression of metabolic enzymes and transporters involved...Full Text Available
The aspartate receptor involved in chemotaxis is modified by methyl esterification at four distinct glutamate residues during the adaptive response of this receptor. To explain the high degree of specificity...Full Text Available
Selective estrogen receptor modulators (SERMs) represent a class with a growing number of compounds that act as either estrogen receptor agonists or antagonists in a tissue-specific manner. This article...Full Text Available
The adenovirus fiber knob causes the first step in the interaction of adenovirus with cell membrane receptors. To obtain information on the receptor binding site(s), the interaction of labeled cell...Full Text Available
BackgroundThe epidermal growth factor receptor (Egfr) with its numerous ligands has fundamental roles in development, cell differentiation and physiology. Dysfunction of the receptor-ligand...Full Text Available
Chemokine receptors control leukocyte chemotaxis and cell-cell communication but have also been associated with pathogen entry. GPR33, an orphan member of the chemokine-like receptor family,...Full Text Available
1. The effects of stimulation of atrial receptors on hypothalamic neurosecretory cells were investigated in anaesthetized dogs and cats. Atrial receptors were activated by stretching the left and the...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
A specific immunoglobulin, the receptor antibody, can be found in most patients with myasthenia gravis. In order to study the kinetic properties of this antibody, serial determinations of receptor antibody,...Full Text Available
Background:Increasing evidence shows the importance of young age, estrogen receptor (ER), progesterone receptor (PR) status, and HER-2 expression in patients with breast cancers.Patients...Full Text Available
Activation of beta-adrenergic or muscarinic acetylcholine receptors expressed in transfected cells or epidermal growth factor receptors in human keratinocytes produces 15% to 200% changes in cellular...Full Text Available
BACKGROUND: H2-histamine receptors mediate a wide range of physiological functions extending from stimulation of gastric acid secretion to induction of human promyelocyte differentiation. We have previously...Full Text Available
The vanilloid receptor-1 (VR1, or transient receptor potential vanilloid-1 receptor, TRPV1) is activated by capsaicin, the key ingredient of hot peppers. TRPV1 was originally described on sensory neurons...Full Text Available
Unlike in normal rabbits, pulmonary rapidly adapting receptors (RARs) in rabbits with chronic mitral regurgitation (MR) do not respond to small changes in extravascular...Full Text Available
Histamine and the histamine receptors are important regulators of a plethora of biological processes, including immediate hypersensitivity reactions and acid secretion in the stomach. In these...Full Text Available
Halothane, chloroform, and carbon tetrachloride, in the vapor and liquid phases, stimulate the water receptor of the blowfly Phormia regina. There are three successive phases of response to long-lasting...Full Text Available
Insulitis is considered the histopathological hallmark of type I diabetes. In the non-obese diabetic (NOD) mouse, diabetes has never been observed in the absence of insulitis. The in vivo detection of insulitis could be of relevance for early prediction of diabetes. As approximately 15% of islet-infiltrating lymphocytes express interleukin 2 receptors, the authors have labelled recombinant inter-leukin 2 with "1"2"3I and used this radiopharmaceutical to detect insulitis by gamma camera imaging. The authors studied 71 prediabetic NOD and 27 normal Balb/c mice. Labelled #alpha#-lactalbumin was used as the control protein. In the first set of experiments the tissue distribution of radiolabelled interleukin 2 in isolated organs from animals sacrificed at different time points was studied. Higher radioactivity was detected in the pancreas of NOD mice injected with labelled interleukin 2, as compared to NOD mice receiving labelled ...
BackgroundThe effects of single or combined histamine H1-receptor and leukotriene CysLT1-receptor antagonism on nasal adenosine monophosphate (AMP) challenge...Full Text Available
BackgroundThe orphan nuclear receptor estrogen-related receptor α (ERRα) is a member of the nuclear receptor superfamily. It was identified through a search for genes...Full Text Available
Although the radioreceptor method is widely used for estrogen receptor assay in human tissue, it has several limitations and a number of alternative methods are being explored. An immunohistochemical method of estrogen receptor assay using a specific antibody to estradiol has been proposed as a suitable alternative. The present study was designed to evaluate the validity of this method in detecting true estrogen receptors in human tumor tissue. Using radioiodinated antibody to estrogen, we have demonstrated that the estrogen antibody can detect the estrogen when it is bound to 4S type receptor but is unable to bind to estrogen when the hormone is bound to 8S type receptor. Our observations suggest that the immunohistochemical method of detection of intracellular cytosolic receptor for estrogen is not a suitable alternative to the currently used radioreceptor ...
Strain embrittlement in Ti base alloys during tensile testing was investigated. Results show that in an #alpha#-#beta# titanium alloy the local activity of H in alpha phase (#alpha#/sub H//sup #alpha#) increases and activity of H in beta phase (#alpha#/sub H//sup #beta#) decreases as the equiaxed #alpha# particle size decreases at constant volume fraction of phases. Thus with decreasing particle size there would be a tendency for H to move from #alpha# to #beta#, decreasing the H content of #alpha#. Also whether H tended to move from #beta# to #alpha# or from #alpha# interiors to the #alpha#-#beta# interface this tendency would be reduced by surface tension effects, making the alloy less susceptible to embrittlement.
Insulin receptors on the surface of isolated rat adipocytes were photoaffinity labeled at 12 degrees C with the iodinated photoreactive insulin analogue, 125I-B2 (2-nitro-4-azidophenylacetyl)-des-PheB1-insulin, and the pathways in the intracellular processing of the labeled receptors were studied at 37 degrees C. During 37 degrees C incubations, the labeled 440-kDa insulin receptors were continuously internalized (as assessed by trypsin inaccessibility) and degraded such that up to 50% of the initially labeled receptors were lost by 120 min. Metabolic poisons (0.125-0.75 mM 2,4-dinitrophenol (DNP) and 1-10 mM NaF), which led to dose-dependent depletion of adipocyte ATP pools, inhibited receptor loss, and caused up to 3-fold increase in intracellular receptor accumulation. This effect was due to inhibition of intracellular receptor ...
The drug-binding properties of human alpha-foetoprotein (alpha FP) were investigated by a fluorescence-spectral method. Human alpha FP was shown to bind to albumin's site I marker (warfarin, phenylbutazone),...Full Text Available
The emission lines H#alpha#, H#beta#+[OIII], and L#alpha# have been observed in the high-redshift quasar 1225+31. The ratios of line intensities in 1225+31 are found to be L#alpha#/H#alpha#approx.0.8, H#alpha#/(H#beta#+[OIII]) approx.4, and 4alpha#/H#beta#<10. The observed value of L#alpha#/H#alpha# agrees well with the ratio derived by Baldwin on the basis of a composite quasar spectrum, and with direct determination of this ratio in 3C 273 and PKS 0237--23. The ratio H#alpha#/H#beta# is in the range of values found for a sample of low-redshift quasars by Baldwin. The low value for the L#alpha#/H#alpha# ratio cannot be reasonably explained by foreground extinction between the Sun and 1225+31.
We have identified another Drosophila GTP-binding protein (G protein) alpha subunit, dGq alpha-3. Transcripts encoding dGq alpha-3 are derived from alternative splicing of the dGq alpha locus previously...Full Text Available
Summary Metabotropic GABAB receptors play a fundamental role in modulating the excitability of neurons and circuits throughout the brain. These receptors influence synaptic transmission by inhibiting presynaptic release or activating postsynaptic potassium channels. However, their ability to directly influence different types of postsynaptic glutamate receptors remains unresolved. Here we examine GABAB receptor modulation in layer 2/3 pyramidal neurons from the mouse prefrontal cortex. We use two-photon laser-scanning microscopy to study synaptic modulation at individual dendritic spines. Using two-photon optical quantal analysis, we first demonstrate robust presynaptic modulation of multivesicular release at single synapses. Using two-photon glutamate uncaging, we then reveal that GABAB r...
A clone encoding a human D{sub 2} dopamine receptor was isolated from a pituitary cDNA library and sequenced. The deduced protein sequence is 96% identical with that of the cloned rat receptor with one major difference: the human receptor contains an additional 29 amino acids in its putative third cytoplasmic loop. Southern blotting demonstrated the presence of only one human D{sub 2} receptor gene. Two overlapping phage containing the gene were isolated and characterized. DNA sequence analysis of these clones showed that the coding sequence is interrupted by six introns and that the additional amino acids present in the human pituitary receptor are encoded by a single exon of 87 base pairs. The involvement of this sequence in alternative splicing and its biological significance are discussed.
The experiment on the determination of the tensor polarization of the residual nucleus is described for the reaction "6Li (#alpha#, #alpha#') "6Li. It is based on the unique connection of polarization tensors t_l_m of the residual nucleus for the reaction (#alpha#, #alpha#') and the angular correlation function W (#omega#_1, #omega#_2) for #alpha#'-particle and decay product of this nucleus, where #omega#_1, #omega#_2 are motion directions of #alpha#'-particle and decay product. The angular correlations of #alpha#'-particle and deuteron are measured for the "6Li (#alpha#, #alpha#', d)"4He reaction on the 27.2 MeV #alpha#-particle beam. The recording system consists of six silicon detectors and provides the energy resolution about 0.8 MeV and the angular resolution #+-# 3 deg. The ...
A series of #alpha#-sialon (#alpha#') compositions containing mixed stabilising cations were prepared, by introducing additional CaO to a basic Sm #alpha#-sialon compositions. The thermal stability of these Sm-Ca-containing #alpha#-sialon phases was investigated using XRD, SEM and EDXS techniques. It was found that the addition of calcium into the Sm #alpha#-sialon systems greatly improved the stability of the #alpha#-sialon phases. Calcium was found to be incorporated into the #alpha#-sialon structure, coexistent with the samarium, and partitioning of the calcium and samarium was observed between the #alpha#' phase and grain boundary phases. This indicates a technique which may be used to improve the thermal stability of the #alpha#' phase while maintaining good refractory phases at the sialon grain ...
Aim: Several studies have investigated the expression of the cytokeratins (CKs), vimentin, the epithelial growth factor receptor (EGFR), the oestrogen receptor (ER), and the progesterone...Full Text Available
The GABA-modulating and GABA-mimetic activities of the monoterpenoid thymol were explored on human GABAA and Drosophila melanogaster...Full Text Available
The purpose of this study was to determine whether resistance exercise training-induced reductions in inflammation are mediated via melanocortin 3 receptor expression in obese (BMI 32.7 ± 3.7)...Full Text Available
The plant hormone cytokinin is perceived by membrane-located sensor histidine kinases. Arabidopsis (Arabidopsis thaliana) possesses three cytokinin receptors: ARABIDOPSIS HISTIDINE...Full Text Available
BackgroundThe aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that mediates the toxicity and biological activity of dioxins and related chemicals. The...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
SUMMARYThe cytolytic activity of natural killer (NK) cells is regulated by inhibitory receptors that detect the absence of self molecules on target cells. Structural studies of...Full Text Available
Current concepts of the pathogenesis of sarcoidosis suggest that the expanded numbers of activated T-helper/inducer cells at sites of disease activity result, at least in part, from their proliferation...Full Text Available
Taste cells use multiple signaling mechanisms to generate appropriate cellular responses to discrete taste stimuli. Some taste stimuli activate G protein coupled receptors (GPCRs) that cause calcium...Full Text Available
The normal physiological contraction of the urinary bladder, which is required for voiding, is predominantly mediated by muscarinic receptors, primarily the M3 subtype, with the M2...Full Text Available
G-protein-coupled receptor signalling has been suggested to be voltage dependent in a number of cell types; however, the limits of sensitivity of this potentially important phenomenon are unknown. Using...Full Text Available
Nuclear hormone receptors comprise a characteristic family of transcription factors found in vertebrates, insects and nematodes. Here we show by cDNA and gene cloning that a Cnidarian, Tripedalia...Full Text Available
We previously reported that global deletion of insulin receptor substrate protein 1 (Irs1) extends lifespan and increases resistance to several age-related pathologies in female mice....Full Text Available
1. The structural requirements of an allosteric barbiturate binding site on acetylcholine receptor-rich membranes isolated from Torpedo electroplaques have been characterized by the ability of fourteen...Full Text Available
Growth hormone (GH) has an important role in the regulation of hepatic LDL receptor expression and plasma lipoprotein levels. This investigation was undertaken to evaluate if these effects of GH on...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
There is increasing evidence that receptor-mediated events impact one or more stages responsible for tumor development in experimental animals and humans. Although many chemicals and endogenous hormones...Full Text Available
The presence of albumin structures with the capacity to bind to a surface receptor in group C and G streptococci was studied in serum samples from 45 mammalian species representing 15 different orders,...Full Text Available
Epidermal growth factor receptor (EGFR) kinase domain mutations hyperactivate the kinase and confer kinase addiction of the non-small-cell lung cancer (NSCLC) tumor...Full Text Available
Binding of epidermal growth factor (EGF) to the EGF receptor (EGFR) initiates signal transduction, ultimately leading to altered gene expression. Ligand-activated EGFR is also rapidly internalized...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
Epidermal growth factor receptor (EGFR) related therapies – mainly tyrosine kinase inhibitors (TKIs) such as erlotinib and gefitinib, but also monoclonal antibodies targeting EGFR, for example,...Full Text Available
BackgroundPolymorphisms in Epidermal Growth Factor Receptor (EGFR) gene may influence EGFR production and/or activity, thereby modulating susceptibility to lung...Full Text Available
Antagonists for kainate receptors (KARs), a family of glutamate-gated ion channels, are efficacious in a number of animal models of neuropathologies, including epilepsy, migraine pain, and anxiety....Full Text Available
Ionotropic P2X and metabotropic P2Y purinergic receptors are expressed in the central nervous system and participate in the synaptic process particularly associated with acetylcholine, GABA, and glutamate...Full Text Available
Gastrointestinal stromal tumors (GIST) are thought to derive from the interstitial cells of Cajal (ICC) or an ICC precursor. Oncogenic mutations of the KIT or PDGFRA receptor tyrosine kinases are present...Full Text Available
The 37/67-kd laminin receptor, LAMR, is a multifunctional protein that associates with the 40S ribosomal subunit and also localizes to the cell membrane to interact with the extracellular matrix. LAMR...Full Text Available
BackgroundApolipoprotein E (ApoE), a cholesterol carrier associated with atherosclerosis, is a major risk factor for Alzheimer's disease (AD). The low-density lipoprotein receptor...Full Text Available
We have characterized the kinetic response of gene targets throughout the murine genome to transcriptional modulation by the glucocorticoid receptor (GR). In contrast to a model in which multiple genes...Full Text Available
The receptors for IGF-I (IGF-IR) and insulin (IR) have been implicated in physiological cardiac growth, but it is unknown whether IGF-IR or IR signaling are critically required. We generated mice with...Full Text Available
TCDD and other polyhalogenated aromatic hydrocarbon ligands of the aryl hydrocarbon receptor (AHR) have been classically considered as non-genotoxic compounds because they fail to be directly mutagenic...Full Text Available
Osteoblasts are the primary cells responsible for bone formation. They also support osteoclast formation from bone marrow precursors in response to osteotropic factors by inducing receptor activator...Full Text Available
The murine cytomegalovirus (MCMV) M33 gene is conserved among all betaherpesviruses and encodes a homologue of seven-transmembrane receptors (7TMR) with the capacity for constitutive signaling. Previous...Full Text Available
To study the expression of Fc receptors in human alveolar macrophages (AM), the cells were collected from 12 healthy controls and 22 patients with sarcoidosis and the activity involved in binding to...Full Text Available
TSH receptor (TSHR) plays a central role in regulating thyroid function and is targeted by IgGs in Graves’ disease (GD-IgG). Whether TSHR is involved in the pathogenesis of thyroid associated...Full Text Available
Dysregulation of glutamate neurotransmission may play a role in cognitive deficits in schizophrenia. Manipulation of glutamate signaling using drugs acting at metabotropic glutamate receptors...Full Text Available
The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that mediates the toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin. However, the role of the AHR...Full Text Available
OBJECTIVEPrevious studies showed that genetic deletion or pharmacological blockade of the receptor for advanced glycation end products (RAGE) prevents the early structural changes...Full Text Available
The cellular receptor for murine coronavirus mouse hepatitis virus (MHV)-A59 is a member of the carcinoembryonic antigen (CEA) family of glycoproteins in the immunoglobulin superfamily. We isolated...Full Text Available
Astrocytes have long been perceived only as structural and supporting cells within the central nervous system (CNS). However, the discovery that these glial cells may potentially express receptors capable...Full Text Available
The extracellular domain of human fibroblast growth factor receptor (XC-FGF-R) was expressed in Escherichia coli. The protein was purified to homogeneity and the interaction with basic fibroblast growth...Full Text Available
Muscarinic cholinergic receptors modulate dopaminergic function in brain pathways thought to mediate cocaine's abuse-related effects. Here, we sought to confirm 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
The Wistar Kyoto (WKY) rat strain is a putative genetic model of comorbid depression and anxiety. Previous research showing increased κ-opioid receptor (KOR)...Full Text Available
The acetylcholine receptor from the electric tissue of Torpedo californica is a large, integral membrane protein containing four different types of polypeptide chains. The structure of the purified...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
Single-channel currents from acetylcholine receptor channels of garter snake neuromuscular junctions were recorded using the patch-clamp technique. Low concentrations of acetylcholine or carbamylcholine...Full Text Available
IntroductionVarious multigene predictors of breast cancer clinical outcome have been commercialized, but proved to be prognostic only for hormone receptor (HR) subsets overexpressing...Full Text Available
BACKGROUNDOff-pump coronary artery bypass (OPCAB) surgery is associated with a hypercoagulable state in which the platelet thrombin receptor, protease-activated receptor-1...Full Text Available
Gamma interferon (IFN-γ) and the cellular responses induced by it are essential for controlling mycobacterial infections. Most patients bearing an IFN-γ receptor ligand-binding chain...Full Text Available
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 ...
Human chorionic gonadotropin (hCG) is a glycoprotein hormone, secreted by the syncytiotrophoblast cells of the fertilized ovum, that enters the maternal circulation at the time of endometrial implantation. It is composed of two nonidentical subunits; ..cap alpha.. and ..beta.., with molecular weights of 14 kD and 23 kD, respectively. Human chorionic gonadotropin binds to the same receptor as hLH and displays the same biological response, namely, to stimulate the declining function of the corpus luteum to produce progestins and estrogen late in the menstrual cycle. The differences in the structures of hCG and hLH have been exploited to develop antibodies that can measure hCG specifically in the presence of hLH. Two-site antibody binding assays have been developed, based on a surface immunological concept of hCG epitopes, that involve four distinct regions to which antibodies against hCG can bind simultaneously. Antibody cooperative effects, in ...
Influenza virus infection during pregnancy has been implicated as one of cause of premature delivery, abortion and stillbirth. We have reported that cultured human fetal membrane chorion cells undergoing apoptosis by influenza virus infection secrete unidentified heat-stable monocyte differentiation-inducing (MDI) factors. In this study, cellular, biological and immunochemical characteristics of MDI factors were investigated using human monocytic leukemia THP-1 cells by nitroblue tetrazolium reduction and cell adhesion assays. The treatment of THP-1 cells with culture supernatants from the influenza virus-infected chorion cells induced the nitroblue tetrazolium reduction ability, which was inhibited by the addition of superoxide dismutase and diphenyleneiodonium chloride, an inhibitor for reduced nicotinamide adenine dinucleotide phosphate oxidase. The phenomenon was also observed in human peripheral blood monocytes and histiocytic leukemia U937 cells, but not in promyelocytic leukemia ...
Glycyrrhiza glabra root is one of the common traditional Chinese medicines and used as flavoring and sweetening agents for tobaccos, chewing gums, candies, toothpaste and beverages. While glycyrrhizin is one of the main components in the extract of G. glabra root and has been characterized, the other components have not been well characterized. The mechanism of growth activation of breast cancer MCF-7 cells, including the activation of Erk1/2 and Akt, and the transcriptional regulation of estrogen-responsive genes, was examined by means of sulforhodamine B, luciferase reporter gene, real-time RT-PCR and Western blotting assays after the induction of the cells with the extract of G. glabra root. The extract has similar activity to that induced by 17beta-estradiol (E(2)), although glycyrrhizin did not show such an activity. Moreover, the estrogen receptoralpha-dependent neurite outgrowth induced by the extract was similar to that by E(2), ...
Using U-120 cyclotron in the course of correlation experiment one studied mechanisms of excitation and decay of "1"2C nucleus states resulting from irradiation of deuterium-polyethylene target by 27.2 MeV energy #alpha#-particle beam via recording of #alpha#-#alpha#-coincidence simultaneously with investigations of #alpha# + d-interactions. Production of "1"2C excited states decaying with the escape of #alpha#-particle and "8Be nucleus in the ground and the excited states is the basic mechanism of the studied #alpha# + "1"2C interaction
Long-Range Alpha Detector (LRAD) systems are designed to monitor alpha contamination by measuring the number of ions in the air. Alpha particles are a form of ionizing radiation and a typical 5-MeV alpha particle will create about 150,000 ion pairs in air. Field tests at various DOE sites have shown that LRAD Surface Soil Monitors (SSM), Sample Monitors, and Object Monitors are faster and more sensitive than traditional alpha detectors for measuring alpha contamination. This paper discusses the various applications of LRAD technology to low-level radioactive waste management.
The adsorption properties of four samples of the #alpha#-modification of boron nitride (#alpha#-BN) were investigated by the gas-chromatographic method. According to the electron microscopy data, the #alpha#-BN particles possess the shape of thin plates. An #alpha#-BN sample prepared from magnesium polyboride, is the most uniform adsorbent. For a series of n-alkanes, benzene, and alkyl benzenes, by testing the #alpha#-BN samples one has obtained the retained volumes (Henry constants) and the values of the differential adsorption heat, which are close to those of the surface zero filling. These thermodynamic characteristics of adsorption have shown that the #alpha#-BN, line the graphitized thermal carbon black, is not a specific adsorbent.
BackgroundTo evaluate whether P2X receptors are involved in responses to noxious pulp stimulation, the P2X3 and P2X2/3 receptor agonist α,β-methyleneATP...Full Text Available
P2X1 receptors for ATP contribute to signalling in a variety of cell types and following stimulation undergo rapid desensitisation (within 1 s), and require ∼5 min to recover. In HEK293 cells...Full Text Available
SummaryThe transcriptional co-repressor SMRT utilizes two major receptor interacting domains (RID1 and RID2) to mediate nuclear receptor (NR) signaling through epigenetic modification....Full Text Available
The capacity of bones to adjust their mass and architecture to withstand the loads of everyday activity derives from the ability of their resident cells to respond appropriately to the strains engendered....Full Text Available
The 37/67 kDa laminin receptor (LAMR) is a multifunctional protein, acting as an extracellular receptor, localizing to the nucleus, and playing roles in rRNA processing and ribosome assembly....Full Text Available
Dopamine (DA) D3 and D2 receptor mechanisms are implicated in cocaine's abuse-related behavioral effects, but the relative contribution of the two receptor subtypes is only partially characterized....Full Text Available
We have cloned and characterized a 77-kDa oestrogen receptor (ER) from an oestrogen-independent subclone of the MCF-7 human breast cancer cell line. This receptor contains an in-frame, tandem duplication...Full Text Available
The formation of #alpha#'-sialon using Li as a modifying cation was investigated. The effects of the Li content, firing temperatures and Si/Al ratios on #alpha#'- yield were studied. The results indicated that at lower sintering temperatures the stabilisation of #alpha#'-sialons was obtained but the high weight losses of Li at higher temperatures limited the stabilisation. Increased ''Al'' content in the compositions resulted in an increase in the stability of Li-#alpha#'-sialon at higher temperatures, by the formation of a liquid phase which retains Li in the system. (orig.).
The advance in the analysis of very small amount (<= 1#alpha#/cm"2h) of #alpha#-emitters in the cited materials is reviewed. The review, for which 75 references are listed, covers the period from January, 1978, to June, 1982. The use of #alpha#-ray counting, #alpha#-ray spectrometry, #gamma#-ray spectrometry, neutron activation analysis and mass spectrometry is discussed, and their relative merit and limitation are outlined. (J.P.N.).
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 ...
Schindler disease is a recently recognized infantile neuroaxonal dystrophy resulting from the deficient activity of the lysosomal hydrolase, alpha-N-acetylgalctosaminidase (alpha-GalNAc). The recent...Full Text Available
The results of a study of the expression of embryonic hemoglobin genes in mice which show an imbalance of alpha and non-alpha chain synthesis are reported. (ACR)
Quantitative metallography is often used to confirm the proper processing of aerospace metallic materials. A microstructural feature of great importance for titanium alloys processed in the alpha-beta phase field is the volume fraction of primary alpha. S...
Heavy quark production in $\\gamma\\gamma$ collisions is analyzed within the approach to hard collisions of photons recently proposed by the author. In this approach evaluating the cross section $\\sigma(\\gamma\\gamma\\to Q\\bar{Q})$ in the ``next-to-leading order of QCD'' requires the inclusion of direct photon contributions up to the order $\\alpha^2\\alpha_s^2$, whereas in the standard approach direct photon terms only up to the order $\\alpha^2\\alpha_s$ are taken into account. Phenomenological consequences of this difference are discussed.
ObjectiveTo assess whether 17 alpha-hydroxyprogesterone caproate reduces the rate of preterm birth in women carrying triplets.MethodsFull Text Available
Phase transformations from #alpha#- to #beta#-SiAlONs (i.e., from #alpha#' to #beta#') have been recently reported in a number of rare-earth SiAlON systems during postsintering heat treatment. In the present work, this transformation process in a Sm (#alpha# + #beta#)-SiAlON material is studied by using XRD, TEM, and EDS X-ray mapping techniques. It is observed that in addition to the formation of #beta#' and M' phases, the #alpha#'-to-#beta#' transformation is accompanied by a significant increase in the amount of an AlN-polytypoid phase. The results suggest that some #alpha#' phases are thermodynamically unstable at temperatures lower than the material sintering temperature and will decompose when conditions allow. For the composition studied in this work, the #alpha#-SiAlON decomposition can be described in general as #alpha#' #-># ...
Alpha-toxin, the major cytotoxic agent elaborated by Staphylococcus aureus, was the first bacterial exotoxin to be identified as a pore former. The protein is secreted as a single-chain, water-soluble...Full Text Available
The study of the {alpha}-particle energy distributions associated with ND and SD states in {sup 151,152}Dy has been carried out. The Dy isotopes were produced in the reaction {sup 37}Cl+{sup 123}Sb at 191 MeV via the ({alpha}5n) and ({alpha}4n) channels, respectively. In {sup 151}Dy the {alpha}-particle energy distributions associated to ND and SD are very different from each other, both at the low and high energy sides inducing a difference of 3 MeV in the {alpha}-particle mean energy. In {sup 152}Dy the situation is different; the {alpha}-particle spectral shapes are similar and a difference in the {alpha}-particle mean energy of only 0.7 MeV is deduced. A description in terms of energy localization of entry states is given. (orig.)
Abnormalities of dystrophin, the sarcoglycans, and laminin alpha2 are responsible for a subset of the muscular dystrophies. In this study we aim to characterise the nature and frequency of abnormalities...Full Text Available
Incorporation of /sup 32/P from (gamma-32P)ATP into tyrosine residues of the insulin-like growth factor (IGF)-II receptor was observed in a Triton X-100-insoluble fraction of rat adipocyte plasma membranes. IGF-II receptor phosphorylation proceeded to a stoichiometry of approximately 0.5 mol of phosphate/IGF-II binding site after 10 min of incubation at 4 degrees C. A Km for ATP of 6 microM was calculated for this phosphorylation reaction. Addition of IGF-II caused an approximately 2-fold increase in tyrosine phosphorylation of the IGF-II receptor in this preparation. In contrast, phosphorylation of angiotensin II by the Triton X-100 washed membranes was not stimulated by IGF-II. Incubation of purified receptor immobilized on IGF-II agarose or of receptor-enriched low density microsomal membranes with (gamma-32P)ATP did not result in appreciable incorporation of (/sup 32/P)phosphate ...
The authors have investigated insulin receptor phosphorylation in differentiated cultured BC3H-1 myocytes. As for other insulin-responsive cell systems in partially purified wheat germ agglutinin receptor preparations, insulin stimulates the phosphorylation of its own receptor (95K ..beta..-subunits) in a dose dependent manner (0-400 nM), as identified by immunoprecipitation with antiinsulin receptor antibodies and SDS-PAGE. In the same preparations they show that 12-0-tetradecanyl phorbol acetate (TPA), which in many respect ..beta..-subunits in the same dose dependent manner (0-5 ..mu..M). In addition, antiinsulin receptor antibodies (B-10) also induced phosphorylation of mimics insulin action, also induced phosphorylation of the insulin receptor and HPLC tryptic maps of the /sup 32/P-labeled ..beta..-subunit were identical to those for insulin-induced ...
The maintenance of a balance between cell gain and cell loss is essential for proper liver function. The exact role of aryl hydrocarbon receptor (AhR) in regulating cell proliferation and apoptosis of liver cells remains unclear, since ligand-dependent activation of AhR has been shown to induce cell cycle arrest, proliferation, differentiation or apoptosis, depending on the cellular model used. AhR can directly interact with retinoblastoma protein in hepatic cells, forming protein complexes that can efficiently block cell cycle progression by inducing G1 arrest, or to induce the expression of inhibitors of cyclin-dependent kinases, such as p271. On the other hand, it has been suggested that AhR could play a stimulatory role in cell proliferation, either directly or by mediating a release from contact inhibition. It is now generally accepted that progenitor cells exist in the liver, are activated in various liver diseases and can form a potential target cell ...
The authors have been involved for the last few years in developing high affinity sigma-receptor-specific radiopharmaceuticals for use in nuclear medicine. They recently demonstrated that sigma-1 receptors are expressed in human melanoma cells and that sigma receptors could be used as external markers for non-invasive imaging. In order to determine the presence of sigma receptors in other human tumors they have screened numerous non-small cell lung carcinoma, melanoma and breast cancer cell lines. All of these cell lines expressed high sigma receptor densities using commercially available ["3H]-(+)-pentazocine or ["3H]DTG tritiated sigma ligands. Therefore, a sigma ligand with high affinity in both sigma-1 and sigma-2 subtype pharmacological assays could be potentially useful for imaging a variety of primary and metastatic sites of various origins. The authors describe recent ...
Somatogenic hormones play an important role in regulation of receptors for prolactin (PRL) and estrogen. Plerocercoids of the tapeworm, S. mansonoides produce a factor which mimics some, but not all of the actions reported for GH. Intact female rats were subjected to a constant infusion of plerocercoid growth factor (PGF) via a subcutaneous infection for two weeks to determine if PGF influences receptors for PRL, GH or estradiol. The rate of weight gain in the PGF-treated rats was accelerated in spite of a marked reduction in serum GH. Partially-purified PGF specifically displaced [125I]hGH from rat liver receptors but microsomes prepared from rats treated with PGF specifically bound significantly less [125I]hGH than microsomes from control rats. The reduction in [125I]hGH binding was not due to occupancy or to a change in affinity but to a suppression in receptor concentration. Scatchard analysis of ...
Methylxanthines and their derivatives are antagonists at cell surface adenosine receptors. They report here a systematic study of xanthine structure-activity relationships which compares potency at two adenosine receptor subtypes, R/sub a/ and R/sub i/. Adenylate cyclase stimulation (R/sub a/ in platelet membranes) and inhibition (R/sub i/ in adipocyte membranes) were used as models of receptor activation. K/sub i/ values were obtained by Schild analysis. The orders of potency of the xanthines to attenuate the effects of adenosine analogues were similar to those previously reported. Earlier work utilizing radioligand binding (R/sub i/ and (/sup 3/H) cAMP formation (R/sub a/) claimed that IIX and PACPX are at least 10 and 400 fold, respectively, more potent at R/sub i/ than at R/sub a/. However, in their assays which utilize modulation of receptor-coupled adenylate cyclase, the xanthines show little ...
The Feynman-#alpha# method was applied to measurement of reactivity and the ability of this method for a real-time reactivity monitoring system was assessed. In the experiment, all measured data by BF_3 detectors were stored in a multi-channel scaler controlled by a personal computer, and they were analyzed to obtain prompt neutron decay constant (#alpha#) and reactivity with consideration of dead time of detector. It was found that #alpha# could be obtained almost in a real-time even for both positive and negative reactivities by the present experimental technique. (author).
Tumor necrosis factor alpha (TNF-alpha) plays a central role in activation of first-line defenses of a host against foreign organisms. To determine whether Brucella infection modulated TNF-alpha production,...Full Text Available
The reactions of alpha particles on natural abundance chromium have been studied between 40 and 110 MeV, in order to produce "5"2Fe for medical use. The yield of the reaction "5"2Cr(#alpha#,4n)"5"2Fe for Esub(#alpha#) = 85 #-># 53 MeV is only 30 #mu#Ci/#mu#Ah. (orig.).
Current applications of ..cap alpha..-particle spectrometry in post-irradiation research and reprocessing are reviewed. Implementation of procedures and techniques described in the literature to the particular samples at S.C.K./C.E.N. often results in a combined radiochemical method where ..cap alpha..-particle spectrometry is used to complement or enforce results obtained by other methods. Typical cases are reported and results obtained by different methods are compared to the results obtained by ..cap alpha..-particle spectrometry.
In the present work the excitation functions for the reactions "1"4"1Pr(#alpha#,n)"1"4"4Pm and "1"4"1Pr(#alpha#,2n)"1"4"3Pm have been measured experimentally below 50 MeV #alpha#-particle
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
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
SUMMARYTestosterone and estrogen are essential for male behaviors in vertebrates. How these two signaling pathways interact to control masculinization of the brain and behavior...Full Text Available
The rejection thresholds of Phormia regina Meigen for twenty-four glycols have been determined. A definite relationship between the concentration of the test material and the distribution...Full Text Available
There is considerable evidence that purines are vasoactive molecules involved in the regulation of blood flow. Adenosine is a well known vasodilator that also acts as a modulator of the response to...Full Text Available
Cellular actions of thyroid hormone may be initiated within the cell nucleus, at the plasma membrane, in cytoplasm, and at the mitochondrion. Thyroid hormone nuclear receptors (TRs) mediate the biological...Full Text Available
Laron syndrome (LS) is an autosomal recessively inherited condition characterized by insensitivity to endogenous and exogenous GH. Affected individuals have severe episodes and other characteristic features. GH receptor gene mutations are present in all affected individuals in whom molecular studies have been reported. The GH receptor is a plasma membrane-spanning protein in which the extracellular domain binds circulating GH and the intracellular domain interacts with the JAK-2 kinase and possibly other intracellular signaling molecules. GH receptor dimerization occurs on GH binding and is thought to be required for normal signal transduction. We have studied the GH receptor genes of four unrelated individuals affected with LS from the United States, Italy, Saudi Arabia, and India. We have identified four different missense mutations that alter consecutive amino acids 152 to 155 in or near the ...
A study was made of the kinetics of L-(/sup 3/H)quinuclidinyl benzilate binding with membrane-bound muscarine cholinoreceptors from the rat brain. Determination was made of the rate constants of this process, and constants as a function of ligand concentration was investigated, indicating that there is a complex mechanism of interaction of antagonists with muscarine receptor. With up to 3.5 nM concentrations of L-(/sup 3/H)quinuclidinyl benzilate, the binding reaction occurs in two stages: rapid equilibrated binding is followed by a slow process of conformational isomerization of the receptor-ligand complex. At higher ligand concentrations, there is additional drastic increase in constant of rate of ligand binding a new plateau is reached. Such dependence of rate constant on ligand concentration is indicative of the cooperative nature of interaction between antagonists and muscarine receptors. This is possible if there are ...
The tetrapeptide KDEL is commonly found at the C terminus of soluble proteins of the endoplasmic reticulum (ER), and it contributes to their localization by interacting with a receptor that recycles...Full Text Available
BackgroundWhereas there is increasing evidence that loss of expression and/or function of the thyroid hormone receptors (TRs) could result in a selective advantage for tumor development,...Full Text Available
The receptor occupancy-biological effect relationship for muscarinic receptors in guinea pig ileal smooth muscle has been studied by comparison of radioligand binding and contractile response. Muscarinic receptors in homogenates of ileal smooth muscle were labeled with (/sub 3/H)-1-Quinuclidinyl benzilate. Treatment with propylbenzilylcholine mustard (PrBCM), to inactivate irreversibly muscarinic receptors, caused a large dose dependent rightward shift of the dose-response curve to three agonistic furtrethonium derivatives with a concomitant decrease in maximal response. Using those data, the fraction of receptors remaining unoccupied (q-values) and true affinity constants (-log K/sub A/-values) were calculated. Exposure to 20 or 60 nM PrBCM for 15 minutes resulted in a 39% and a 61% reduction in specific (/sup 3/H)-1-Quinuclidinyl benzilate binding sites respectively to be compared ...
This paper describes attempts to isolate and characterize glycosaminoglycan (GAG)-binding molecules on the surface of lymphocytes and lymphoma cell lines and relate their expression to splenic and lymph...Full Text Available
OBJECTIVES:To investigate the effect of opioid receptor blockade on the myocardial protection conferred by chronic exercise and to compare exercise training with different strategies...Full Text Available
Carbohydrate-directed endocytosis is mediated by a receptor, the hepatic binding protein; it is responsible for the clearance of galactose-terminated glycoproteins from the circulation. This process...Full Text Available
Measurements of the taste thresholds of blowflies for a wide variety of carbohydrates, presented individually and in combination, showed that the stimulating effects of the compounds are not always...Full Text Available
In connection with the different cyclical strengths of the two-phase (#alpha# + #beta#) titanium alloy in the case of the acicular and rounded formations of the #alpha#-phase, we have studied, employing the X-ray diffraction method, the phase composition of the alloy and the influence of heat treatment upon it. Using the method of electronic fractography, we examined the fractures in samples destroyed by the asymmetric twisting, in order to find out why the durability of the alloy is dependent upon the #alpha# - phase structure. It has been found that in the BT22 alloy, the decay the #beta#-phase may proceed in two ways; either with the formation of the martensite #alpha#'-phase of the acicular shape or with the separation of the non-martensite round-shaped #alpha#-phase. The character of the phase transformations #beta# - #alpha# or ...
The interaction between a lower hybrid wave and a fusion alpha particle displaces the alpha particle simultaneously in space and energy. This results in coupled diffusion. Diffusion of alphas down the density gradient could lead to their transferring energy to the wave. This could, in turn, put energy into current drive. Here we calculate numerical solutions for the alpha energy transfer and study a range of conditions that are favourable for wave amplification from alpha energy. We find that it is possible for fusion alpha particles to transfer a large fraction of their energy to the lower hybrid wave. The numerical calculation shows that the net energy transfer is not sensitive to the value of the diffusion coefficient over a wide range of practical values. An extension of this idea, the use of a lossy boundary to enhance the energy transfer, is investigated. ...
The interaction between a lower hybrid wave and a fusion alpha particle displaces the alpha particle simultaneously in space and energy. This results in coupled diffusion. Diffusion of alphas down the density gradient could lead to their transferring energy to the wave. This could, in turn, put energy into current drive. Here we calculate numerical solutions for the alpha energy transfer and study a range of conditions that are favourable for wave amplification from alpha energy. We find that it is possible for fusion alpha particles to transfer a large fraction of their energy to the lower hybrid wave. The numerical calculation shows that the net energy transfer is not sensitive to the value of the diffusion coefficient over a wide range of practical values. An extension of this idea, the use of a lossy boundary to enhance the energy transfer, is investigated. ...
The interaction between a lower hybrid wave and a fusion alpha particle displaces the alpha particle simultaneously in space and energy. This results in coupled diffusion. Diffusion of alphas down the density gradient could lead to their transferring energy to the wave. This could, in turn, put energy into current drive. An initial analytic study was done by Fisch and Rax. Here the authors calculate numerical solutions for the alpha energy transfer and study a range of conditions that are favorable for wave amplification from alpha energy. They find that it is possible for fusion alpha particles to transfer a large fraction of their energy to the lower hybrid wave. The numerical calculation shows that the net energy transfer is not sensitive to the value of the diffusion coefficient over a wide range of practical values. An extension of this idea, the use of a ...
The experiments show that the fluence threshold of 316L SS irradiated by 1.8 MeV alpha particle is between (0.8655-1.3457) x 10"1"8 #alpha#/cm"2, and the threshold decreases in the 1.5 MeV and 1.0 MeV alpha particle irradiation. For the solid solution samples irradiated by 1.5 MeV alpha particle, the threshold is below 0.5595 x 10"1"8#alpha#/cm"2, and for the 20% cold-worked sample, the threshold is between (0.8595-0.5063) x 10"1"8 #alpha#/cm"2. In 1.0 MeV alpha particle irradiation, the threshold for the solid solution sample and 20% cold-worked sample is between (0.3073-0.1024) x 10"1"8 #alpha#/cm"2 and (0.4108-0.3063) x 10"1"8 #alpha#/cm"2 respectively. The difference of threshold of the two kinds of samples shows that the 20% cold-working can influence the occurrence of blistering
The "2H(#alpha#,p#alpha#)n reaction was investigated in a kinematically complete experiment with a #alpha#-beam at energy 27.2 MeV.The "5He excited state was observed and its parameters were determinate.Coincidence spectra were fitted by contribution of sequential decay through the "5He ground and excited states.The best agreement with the data was obtained assuming the following "5He excited state parameters: E_a_n=2.8 MeV #GAMMA#=2.5 MeV.
Phase transformations occuring during cold deformation in hardened #alpha#+#beta# titanium alloy of the Ti-Al-Mo-Zr-Sn-Si system with 10% summary content of alloying elements are studied by X-ray diffraction analysis. Two stages of trapsformation of metastable #alpha#''-phase are found. A conclusiop is made that ability of the alloy containing #alpha#''-phase to cold deformation is determined by the presence of favourable texture, by high degree of metastability and by volume portion of #alpha#''-phase in the alloy structure.
The neutron transition multipole moment, M/sub n/, for (0"+#->#2"+, 1.84 MeV) transition is inferred by measuring the (#alpha#,#alpha#') angular distribution at E/sub #alpha#/ = 50 MeV and comparing it with a microscopic distorted-wave Born approximation calculation. Proton transition densities are taken from electron scattering data. M/sub n//M/sub p/ is found to be substantially less than N/Z in agreement with the (p,p') result.
In the case of inelastic scattering of alpha particles to the 3"+ state, the averaged angular distributions show a characteristic shape, corresponding to the excitation of such an unnatural parity state by alpha particles in the compound nucleus process. The modified Hauser-Feshbach cross-section calculations give a good description of the averaged distributions for the alpha particle scattering to the 3"+ state and the compound nucleus parameters could be extracted. The calculations of the compounds nucleus contributions to the other states in the case of 24 MeV alpha particle scattering from "2"8Si show that this contribution is not negligible and in the case of the scattering to the 4"+ state seems to be dominant. (Z.M.).
The adsorption properties of four samples of ..cap alpha..-BN were studied by means of gas chromatography. The particles of ..cap alpha..-BN particles, according to data obtained by electron microscopy, have the shape of thin platelets. A sample of ..cap alpha..-BN prepared from magnesium polyboride was found to be the most nearly homogeneous adsorbent. For a number of n-alkanes, benzene, and alkylbenzenes, data have been obtained on the retention volumes (Henry constants) and the differential heats of adsorption for surface coverages approaching zero. These thermodynamic data on the adsorption showed that ..cap alpha..-BN, like graphitized thermal carbon black, is a nonspecific adsorbent.
Both microstructural graded and homogenous single-phase #alpha#-Sialon is obtained from Si_3N_4 powder for a broad range of compositions of practical interest. Elongated grains of #alpha#-Sialon could be developed in the monophase material by controlled mechanism of nucleation and growth. Tailoring of microstructure was realized through slow transformation reaction from Si_3N_4 to #alpha#-Sialon at lower temperature than sintering temperature when the composition is near the #alpha#-Sialon phase boundary. The mechanical properties are strongly correlated with the microstructure and are enhanced greatly in the optimized Sialon composition. (author)
SummaryThe receptors for the second messenger InsP3 comprise a family of closely related ion channels that release Ca2+ from intracellular stores, most prominently...Full Text Available
BackgroundCannabinoids represent unique compounds for treating tumors, including astrocytomas. Whether CB1 and CB2receptors mediate this therapeutic effect...Full Text Available
BackgroundThe status of estrogen receptor-α (ERα) is critical to the clinical prognosis and therapeutic approach in breast cancer. ERα-negative breast cancer...Full Text Available
Background2-Methylthioadenosine 5'-triphosphate (2-MeSATP), formerly regarded as a specific P2Y (metabotropic) purinergic receptor agonist, stimulates Ca2+ influx and...Full Text Available
1. The induction of long-term potentiation (LTP) was investigated in the rat dentate gyrus in the presence of ryanodine, an agent which is known to selectively bind to the ryanodine receptor (RyR) Ca2+...Full Text Available
The Epstein-Barr virus protein, LMP1, is a functional mimic of the cellular receptor CD40, but signals to B lymphocytes in an amplified and sustained manner compared to CD40. LMP1 contributes...Full Text Available
1. The effects on micturition of RP 67,580, a selective NK1 receptor antagonist, and SR 48,968, a highly, potent antagonist at NK2 receptor sites, given intrathecally (i.t.) or intra-arterially (i.a.)...Full Text Available
σ-Receptor (σR) antagonists have been reported to block certain effects of psychostimulant drugs. The present study examined the effects of σR ligands in rats trained to self-administer...Full Text Available
We have previously described an allelic polymorphism in the V beta 6.1 T-cell receptor gene. The V beta 6.1B allele is associated with disease in a subgroup of patients with juvenile rheumatoid arthritis....Full Text Available
Here, we provide the first study of prolactin (PRL) and prolactin receptor (PRLR) expression during the nonseasonal murine hair cycle, which is, in contrast to sheep, comparable with the human scalp...Full Text Available
Airway ciliated cells express an ATP-gated P2X receptor channel of unknown subunit composition (P2Xcilia) which is modulated by Na+ and by long exposures to ATP. P2Xcilia...Full Text Available
AimsTo characterize the pharmacokinetics of terbogrel, a new combined thromboxane A2 (TxA2) receptor and synthase inhibitor, in healthy human subjects after...Full Text Available
The effects of neuroactive steroids on the function of GABAAreceptors were studied using cell-attached records of single channel activity recorded from HEK293 cells transfected with α1...Full Text Available
Peroxisome proliferator activated receptor-{gamma} (PPAR{gamma}) regulates metabolic homeostasis and adipocyte differentiation, and it is activated by oxidized and nitrated fatty acids. Here we report the crystal structure of the PPAR{gamma} ligand binding domain bound to nitrated linoleic acid, a potent endogenous ligand of PPAR{gamma}. Structural and functional studies of receptor-ligand interactions reveal the molecular basis of PPAR{gamma} discrimination of various naturally occurring fatty acid derivatives.
Asialoorosomucoid (ASOR) is internalized and degraded by HepG2 cells after binding to the asialoglycoprotein (ASGP) receptor, internalization through the coated pit/coated vesicle pathway, and trafficking to lysosomes. Primaquine, an 8-aminoquinoline antimalarial compound, inhibits ASOR degradation at concentrations greater than 0.2 mM by neutralizing intracellular acid compartments. This leads to alterations in surface receptor number, receptor-ligand dissociation, and receptor recycling. We have investigated the effects of primaquine on 125I-ASOR uptake and degradation as a function of primaquine concentration and duration of exposure. Concentrations below those required for neutralization of acidic compartments block 125I-ASOR degradation in HepG2 cells and lead to intracellular ligand accumulation. This effect is maximal at 80 microM primaquine. The intracellular 125I-ASOR is undegraded, dissociated ...
Asialoorosomucoid (ASOR) is internalized and degraded by HepG2 cells after binding to the asialoglycoprotein (ASGP) receptor, internalization through the coated pit/coated vesicle pathway, and trafficking to lysosomes. Primaquine, an 8-aminoquinoline antimalarial compound, inhibits ASOR degradation at concentrations greater than 0.2 mM by neutralizing intracellular acid compartments. This leads to alterations in surface receptor number, receptor-ligand dissociation, and receptor recycling. We have investigated the effects of primaquine on 125I-ASOR uptake and degradation as a function of primaquine concentration and duration of exposure. Concentrations below those required for neutralization of acidic compartments block 125I-ASOR degradation in HepG2 cells and lead to intracellular ligand accumulation. This effect is maximal at 80 microM primaquine. The intracellular 125I-ASOR is undegraded, dissociated ...
Growth differentiation factor-9 (GDF-9), an oocyte-secreted member of the transforming growth factor β superfamily, progesterone receptor, cyclooxygenase 2 (Cox2; Ptgs2), and the EP2 prostaglandin...Full Text Available
Backgroundβ2-Adrenergic receptors (β2AR) play important regulatory roles in a variety of cells and organ systems and are important therapeutic...Full Text Available
An unusual S1-nuclease sensitive microsatellite (STMS) has been found in the single copy, rat polymeric immunoglobulin receptor gene (PIGR) terminal exon. In Fisher rats, elements within or beyond the...Full Text Available
Using an anti-receptor mAb that blocks the attachment of echovirus 7 and related viruses (echoviruses 13, 21, 29 and 33), we have isolated a complementary DNA clone that encodes the human decay-accelerating...Full Text Available
The aim of this study was to investigate cumulus expansion, nuclear maturation and expression of connexin 43, cyclooxygenase-2 and FSH receptor transcripts in equine cumuli oophori during in vivo and...Full Text Available
Bovine leukemia virus (BLV), a retrovirus related to human T-cell leukemia virus types 1 and 2, can induce persistent nonneoplastic expansion of the CD5+ B-cell population, termed...Full Text Available
The substantia nigra pars reticulata (SNR) controls seizures in a sex-specific manner. At postnatal day 15 (P15), SNR infusion of GABAAreceptor agonist muscimol have proconvulsant...Full Text Available
T-cell activation requires the influx of extracellular calcium, although mechanistic details regarding such activation are not fully defined. Here, we show that P2X7receptors play a key...Full Text Available
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
It has been postulated that fetal vascular abnormalities in aryl hydrocarbon receptor null (ahr−/−) mice may alter cardiovascular homeostasis in adulthood....Full Text Available
Adenosine regulates a wide variety of physiological processes via interaction with one or more G-protein-coupled receptors (A1R, A2AR, A2BR, and A3R)....Full Text Available
This report investigates acute changes in the sensitivity of 5-HT1Areceptors in dorsal raphe (dr) neurons in response to elevated serotonin. DR neurons were isolated from adult rats...Full Text Available
α1-Fetoprotein transcription factor (FTF), also known as liver receptor homolog 1 (LRH-1) is highly expressed in liver and intestine, where it is implicated in the regulation...Full Text Available
1-Naphthylphthalamic acid (NPA) is a specific inhibitor of polar auxin transport that blocks carrier-mediated auxin efflux from plant cells. To allow identification of the NPA receptor thought to be...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
The present study has examined for #alpha#/#beta#-Ti alloys the relationship between the morphology and crystallography of Widmanstaetten plates of #alpha#-Ti in colonies within a prior grain of #beta#-Ti. Thus, optical metallography, scanning electron microscopy and transmission electron microscopy have been used to characterize the morphological features of the microstructure, whereas orientation-imaging microscopy (OM) and transmission electron microscopy (TEM) have been employed to reveal crystallographic information. It has been discovered that within a prior #beta#-Ti grain, although the growth direction of the Widmanstaetten plates in given colonies may differ by large angles from #alpha#-plates in other colonies, they may exhibit very close crystallographic relationships. For example, inclined #alpha#-plates may share common basal planes and be related by a rotation of #approx#10.5 deg. about ...
The "7Be(#alpha#,#gamma#)"1"1C and "7Li(#alpha#,#gamma#)"1"1B reactions are investigated in the three-cluster Generator Coordinate Method. The microscopic wave functions are described from #alpha# and "3He ("3H) clusters, with two coupling modes: #alpha#+"7Be ("7Li) and "3He ("3H)+"8Be. Different internal states of "7Be ("7Li) and "8Be are taken into account. The model is tested on "1"1C and "1"1B spectroscopic properties, which agree fairly well with experiment. We suggest that, in both nuclei, the (3)/(2)"- and (5)/(2)"- states located close to the #alpha#+"7Be ("7Li) threshold, are intruder states. The "7Be(#alpha#,#gamma#)"1"1C and "7Li(#alpha#,#gamma#)"1"1B reaction rates are calculated for temperatures up to 10"9 K. A strong enhancement is found with respect to the reaction rates currently used in astrophysical calculations. ((orig.)).
The loss of #alpha#-globin gene transcriptional activity rarely occurs as an acquired abnormality during the evolution of myeloproliferative disease or preleukemia. To test whether the mutation responsible for the loss of #alpha#-globin gene expression (hemoglobin H disease) in these patients is linked with the #alpha#-globin genes on chromosome 16, the authors transferred chromosome 16 from preleukemic patients with acquired hemoglobin H disease to mouse erythroleukemia cells and measured the transcriptional activity of the human #alpha#-globin genes. After transfer to mouse erythroleukemia cells, the expression of human #alpha#-globin genes from the peripheral blood or marrow cells of preleukemic patients with acquired hemoglobin H disease was similar to that of human #alpha#-globin genes transferred to mouse erythroleukemia cells from normal donors. These ...
Ca #alpha#-sialon is a high hardness material that exhibits in-situ growth of elongated grains during pressureless sintering. This potentially gives the material very good fracture toughness. This paper examined the effects of a number of variables on microstructural development during sintering. The effect of composition was investigated by studying seven different compositions. Densification was seen to be hindered in compositions that produced only small quantities of liquid phase during sintering. Elongated #alpha#-sialon was observed in all the compositions. It was in combination with equiaxed #alpha#--sialon in low liquid compositions, but only elongated #alpha#-sialon was present in the liquid rich compositions. The effects of using P-Si_3N_4 instead of #alpha#-Si_3N_4 starting powders were also examined. Compositions using only #alpha#-S_3N_4 and those ...
Let $M$ be a complex manifold of complex dimension $n+k$. We say that the functions $u_1,...s,u_k$ and the vector fields $\\xi_1,...,\\xi_k$ on $M$ form a \\emph{complex gradient system} if $\\xi_1,...,\\xi_k,J\\xi_1,...,J\\xi_k$ are linearly independent at each point $p\\in M$ and generate an integrable distribution of $TM$ of dimension $2k$ and $du_\\alpha(\\xi_\\beta)=0$, $\\d^c\\u_\\alpha(\\xi_\\beta)=\\delta_{\\alpha\\beta}$ for $\\alpha,\\beta=1,...,k$. We prove a Cauchy theorem for such complex gradient systems with initial data along a $\\CR-$submanifold of type $(\\CRdim,\\CRcodim)$. We also give a complete local characterization for the complex gradient systems which are \\emph{holomorphic} and \\emph{abelian}, which means that the vector fields $\\xi_\\alpha^c=\\xi_\\alpha-J\\xi_\\beta$, $\\alpha=1,...,k$ are holomorphic and satisfy ...
Traditionally wafer bumps are made from Pb containing solders. Over 20 years ago IBM recognized that {sup 210}Pb has a decay chain resulting in a 5.4 MeV alpha particle that induces soft errors. A variety of efforts to produce and characterize low alpha Pb ensued. Work at Honeywell over the past several years has shown that low alpha lead activity does not follow the decay signature predicted from {sup 210}Pb secular equilibrium. Data are presented indicating that smelting has a minimal effect on {sup 210}Pb/{sup 210}Po secular equilibrium and that other trace radionuclides are the alpha source. The implications of these data to possible alpha emitter sources in lead free solders are discussed, along with a method developed by Honeywell to remove alpha emitters from lead free solder components.
The authors used radioligand binding and studies of cell contraction to characterize muscarinic receptors on dispersed smooth muscle cells from rabbit proximal and distal colon. Cells obtained after serial incubations in collagenase were used to measure binding of tritiated quinuclidinyl benzilate (["3H]QNB). At 37 degree C, specific ["3H]QNB binding was saturable and linearly related to cell number. Nonlinear regression analysis was used to determine the affinity of ["3H]QNB for its receptor. The IC_5_0 for the muscarinic agonists bethanechol and oxotremorine were 80 and 0.57 #mu#M, respectively. Hill coefficients were 0.67 for both, suggesting more complex interaction involving receptors of different affinities. In studies of cell contraction, bethanechol stimulated a dose-dependent decrease in cell length with half the maximal contraction occurring at 100 pM. These results suggest that (1) contraction is mediated by ...
The temporal development of the effect of THIP (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol) on the ultrastructure composition and GABA receptor expression in cerebellar granule cells was investigated by quantitative electron microscopy (morphometric analysis) and GABA binding assays. It was found that the cytoplasmic density of smooth endoplasmic reticulum was decreased, while the cytoplasmic density of rough endoplasmic reticulum, Golgi apparatus, vesicles and coated vesicles was greatly enhanced after exposure of the cells to THIP (150 microM) for only 1 hr. In cerebellar granule cells exposed to THIP (150 microM) for 3 hr low affinity GABA receptors were induced. These findings show that the effect of THIP on the ultrastructure composition and GABA receptor expression in cultured cerebellar granule cells may be interrelated and moreover it is likely that the turn-over of GABA receptors is ...
The effects of muscarinic agonists and diisopropylfluorophosphate (DFP) on muscarinic receptor density and muscarinic receptor-mediated responses was assessed in mouse brain and mouse neuroblastoma cells (clone N1E-115). Utilizing the antagonist ({sup 3}H)quinuclidinyl benzilate (({sup 3}H)QNB), there was no difference in the maximal binding capacity (B{sub max}) or equilibrium dissociation constant (K{sub d}) between untreated and 24 hour DFP-treated mice. However, one administration of DFP produced a 24% and 33% decrease in B{sub max} measured by ({sup 3}H)N-methylscopolamine (({sup 3}H)NMS) after 18 and 24 hours which was rapidly reversible within 36 hours after DFP treatment. The loss of ({sup 3}H)NMS binding sites following acute DFP treatment was not accompanied by a change in a particular muscarinic receptor binding conformation. Furthermore, the magnitude of muscarinic receptor-mediated ...
By improving the currently used lactoperoxidase method, we were able to obtain radioiodinated chicken luteinizing hormone (LH) that shows high specific binding and low nonspecific binding to a crude plasma membrane fraction of testicular cells of the domestic fowl and the Japanese quail, and to the ovarian granulosa cells of the Japanese quail. The change we made from the original method consisted of (1) using chicken LH for radioiodination that was not only highly purified but also retained a high receptor binding potency; (2) controlling the level of incorporation of radioiodine into chicken LH molecules by employing a short reaction time and low temperature; and (3) fractionating radioiodinated chicken LH further by gel filtration using high-performance liquid chromatography. Specific radioactivity of the final {sup 125}I-labeled chicken LH preparation was 14 microCi/micrograms. When specific binding was 12-16%, nonspecific binding was as low as 2-4% in the ...
The theory of ..cap alpha.. decay in first-order perturbation theory is presented. The theory is designed for a strongly deformed nucleus in an isomeric state which changes its deformation dynamically through decay from a very deformed to an almost spherical shape. It is shown that other channels are not coupled to the ..cap alpha.. channel in first-order perturbation theory. The collective degrees of freedom of the daughter nucleus are described by shape vibrational states, eigenstates of a Hamiltonian whose potential has two minima. The parent nucleus is described by dynamically coupling the vibrational degrees of freedom to the ..cap alpha..-particle motion and also taking rotations into account. The ..cap alpha.. particle is taken to be a point-like particle. The theory is applied to the ..cap alpha.. decay of the isomeric state of /sub 95//sup 242/Am.
An experiment on the K#beta#/K#alpha# characteristic X-ray intensity ratio in silver was performed at VEC Centre, Calcutta using the #alpha#-beams at energies 40 MeV and 50 MeV employing a Si(Li) detector system on-line. The results show that the K#beta#/K#alpha# X-ray intensity ratio at energies 40 and 50 MeV are 0.215 #+-# 0.006 and 0.216 #+-# 0.006, respectively, which indicates no change with beam energy and in accordance with the earlier reports. The present experiment shows the feasibility of studying the K#beta#/K#alpha# ratios as a function of beam energy in different regions of periodic table. Experiments in elements belonging to the 3d shell and their compounds are suggested to look for the chemical effects and their dependence on #alpha#-energy. (author). 7 refs.
A LLX procedure for carrier-free separation of the radioisotopes, {sup 47}Sc, {sup 48}V and {sup 48},{sup 49},{sup 51}Cr, the 40 MeV {alpha}-particle activation products of titanium has been developed. Sequential separations of the radionuclides produced in the titanium matrix through the nuclear reactions ({alpha}, {alpha}p{chi}n), ({alpha}, p{chi}n) and {alpha}, ({chi}n) have been performed through LLX from aqueous H{sub 2}SO{sub 4} and HClO{sub 4} acid media using the liquid cation exchanger, HDEHP, as an extractant. Purity of the carrier-free radiotracers at different stages of their separations has been verified by {gamma}-ray spectrometry. (author).
The high-frequency data from 12 sensors at the ITCE 1976 are analyzed to determine the Kolmogoroff constants for velocity, temperature and humidity fluctuations, ..cap alpha../sub u/, ..cap alpha../sub T/, and ..cap alpha../sub q/. The occurrence of aliasing in the spectral analysis in some cases together with the limited response of some sensors at the higher frequencies introduces some uncertainties into the analysis. The Soviet sonic anemometer, fine-wire thermometer and infrared hygrometer and the Australian infrared hygrometer provide the best information, namely that: ..cap alpha../sub u/ = 0.59 +/- 0.01, ..cap alpha../sub T/ = 0.68 +/- 0.02, ..cap alpha../sub q/ = 0.76 +/- 0.03, where the errors quoted refer solely to statistical errors. The other instruments provide general support to these values. The technique of using spectral density measurements to ...
Quantitative analytical electron microscopy study of dopant distribution in the microstructure of selected Nd-#alpha#-sialon samples revealed the presence of relatively large amounts of glassy phase at quadruple pockets, which exhibited a common composition similar to a melilite solution. Al segregants were depleted from adjacent grain boundaries to satisfy the 'stoichiometry' of such glass. Existence of this glass results in significant deviation of the Nd-#alpha#-sialon composition from the expected values, which shifts the #alpha#-#beta#-sialon phase boundary. Only extra Nd_2O_3 additives enable a monolithic #alpha#-sialon microstructure. The absence of similar glass in Yb-#alpha#-sialon materials keeps the phase relations from such deviations.
The relative merits and difficlties of the primary and secondry origin hypotheses for the observed cosmic-ray antiprotons, including the new low-energy measurement of Buffington, et al are discussed. We conclude that the cosmic-ray antiproton data may be evidence for antimatter galaxies and baryon symmetric cosmology. The present bar P data are consistent with a primary extragalactic component having /p /equiv 1+/- 3.2/0.7x10 to the -4 independent of energy. We propose that the primary extragalactic cosmic ray antiprotons are most likely from active galaxies and that expected disintegration of bar alpha/alpha ban alpha/alpha. We further predict a value for ban alpha/alpha /equiv 10 to the -5, within range of future cosmic ray detectors.
Results of an experimental study of the interaction of 140 MeV alpha particles with /sup 90/Zr nuclei resulting in fragmentation of the alpha particle are reported. The experimental observations of the study are analyzed and are found to show that alpha particle breakup reactions leading to at least 4-body final states, composed of two charged alpha particle fragments, contribute significantly to the singles yield of charged fragments observed at a fixed forward angle. The conclusions are based on coincidence measurements where one charged fragment is detected at a small forward angle which remains fixed, while the second charged fragment is detected at a series of coplanar secondary angles. The largest coincidence charged particle yield for the multiparticle final state events results from /sup 90/Zr(..cap alpha..,pp)X reactions, where both of the measured protons have energy ...
Results of an experimental study of the interaction of 140 MeV alpha particles with _9_0Zr nuclei resulting in fragmentation of the alpha particle are reported. The experimental observations of the study are analyzed and are found to show that alpha particle breakup reactions leading to at least 4-body final states, composed of two charged alpha particle fragments, contribute significantly to the singles yield of charged fragments observed at a fixed forward angle. The conclusions are based on coincidence measurements where one charged fragment is detected at a small forward angle which remains fixed, while the second charged fragment is detected at a series of coplanar secondary angles. The largest coincidence charged particle yield for the multiparticle final state events results from _9_0Zr(#alpha#,pp)X reactions, where both of the measured protons have energy distributions ...
The high frequency, low mode number toroidicity-induced Alfven eigenmodes (TAE) are shown to be driven unstable by the circulating and/or trapped {alpha}-particles through the wave-particle resonances. Satisfying the resonance condition requires that the {alpha}-particle birth speed v{sub {alpha}} {ge} v{sub A}/2{vert bar}m-nq{vert bar}, where v{sub A} is the Alfven speed, m is the poloidal model number, and n is the toroidal mode number. To destabilize the TAE modes, the inverse Landau damping associated with the {alpha}-particle pressure gradient free energy must overcome the velocity space Landau damping due to both the {alpha}-particles and the core electrons and ions. The growth rate was studied analytically with a perturbative formula derived from the quadratic dispersion relation, and numerically with the aid of the NOVA-K code. Stability criteria in terms of the ...
Angiokeratoma corporis diffusum with glycopeptiduria is a recently recognized inborn error of glycoprotein catabolism resulting from the deficient activity of human alpha-N-acetylgalactosaminidase (E.C....Full Text Available
Treatment of male rat pups from five to 34 days of age with dihydrotestosterone or 5 alpha-androstane-3 alpha, 17 beta-diol, resulted in reduced testicular size at 35 days of age. This appeared to be...Full Text Available
N alpha-Acetylenkephalin carboxypeptidase was co-purified with N-acetyltyrosine deacetylase from monkey kidney. Almost 90% of the activity from the homogenate was recovered in a high-speed supernatant...Full Text Available
Serum protein and lipid concentrations as well as the serum protein binding of propranolol, diazepam and phenytoin were measured in normal weight and obese volunteers. Concentrations of alpha 1-acid...Full Text Available
alpha-actinins are actin microfilament crosslinking proteins. Vertebrate actinins fall into two classes: the broadly-expressed actinins 1 and 4 (actn1 and actn4)...Full Text Available
A total of 262 strains of Staphylococcus aureus isolated from the mammary gland of dairy cows were examined for the production of alpha-hemolysin. Strains were cultured in a liquid medium of casein...Full Text Available
Probabilistic sensitivities using the score function method are developed for a lifing analysis of an alpha + beta titanium alloy in a round bar under axial fatigue load. Sensitivities with respect to the statistical inputs of the crack initiation size (a...
Optimization of radiation shielding for a medium energy accelerator with 60 MeV alpha ions is carried out using the cost-benefit approach. Cost optimum shield thicknesses are estimated for different operating conditions of the accelerator. (author). 5 refs, 1 tab.
1. In normal rats and rats with bladder hypertrophy secondary to outflow obstruction, undergoing continuous cytometry, we examined the responses to the selective alpha 1-adrenoceptor antagonist doxazosin...Full Text Available
Of the many ways of detecting high redshift galaxies, the selection of objects due to their redshifted Ly-alpha emission has become one of the most successful. But what types of galaxies are selected in this way? Until recently, Ly-alpha emitters were understood to be small star-forming galaxies, possible building-blocks of larger galaxies. But with increased number of observations of Ly-alpha emitters at lower redshifts, a new picture emerges. Ly-alpha emitters display strong evolution in their properties from higher to lower redshift. It has previously been shown that the fraction of ultra-luminous infrared galaxies (ULIRGs) among the Ly-alpha emitters increases dramatically between redshift three and two. Here, the fraction of AGN among the LAEs is shown to follow a similar evolutionary path. We argue that Ly-alpha emitters are not a homogeneous class of ...
Dysprosium #alpha#-sialon ceramic has been fabricated from #alpha#-Si_3N_4, AlN, Al_2O_3 and Dy_2O_3 starting powders, using gas pressure sintering at 1800 deg C or higher temperatures under a relatively low gas pressure of 0.9MPa N_2. The resultant #alpha#-sialon grains showed significantly different features, such as equiaxed, elongated, and even a few extraordinarily large with high aspect ratio grains in the fine matrix, which has rarely been observed in #alpha#' ceramics. It is suggested that the temperature strongly influences the grain morphologies of #alpha#-sialon, playing an important role particularly in the latter stage of the 'nucleation-growth' process. Such a microstructural morphology of mixed with equiaxed and elongated grains toughens the #alpha#-sialon ceramics and leaves them still hard. Overly high temperature treatment leads to the ...
Synthesis genes encoding the human #alpha#- and #beta#-globin polypeptides have been expressed from a single operon in Escherichia coli. The #alpha#- and #beta#-globin polypeptides associate into soluble tetramers, incorporate heme, and accumulate to >5% of the total cellular protein. Purified recombinant hemoglobin has the correct stoichiometry of #alpha#- and #beta#-globin chains and contains a full complement of heme. Each globin chain also contains an additional methionine as an extension to the amino terminus. The recombinant hemoglobin has a C_4 reversed-phase HPLC profile essentially identical to that of human hemoglobin A_0 and comigrates with hemoglobin A_0 on SDS/PAGE. The visible spectrum and oxygen affinity are similar to that of native human hemoglobin A_0. The authors have also expressed the #alpha#- and #beta#-globin genes separately and found that the expression of the ...
Experimental, relative intensities for the components of L X-ray were collected from literature, and atomic-number dependency of L#beta#/L#alpha# has been found. (author).
The in vitro antibacterial activities of the newly developed 7 alpha-methoxy cephalosporins and 7 beta-methoxyiminoacetamido cephalosporins against 67 clinical isolates of Bacteroides fragilis and their...Full Text Available
A process is claimed for selectively preparing alpha-olefins having from 2 to about 22 carbon atoms by contacting a gaseous mixture containing carbon monoxide and hydrogen with an iron titanate alkali metal hydroxide catalyst at reaction conditions correlated so as to favor the formation of a substantial proportion of such alpha-olefin product.
In nuclear fuel with a burn-up of 33 kg/t U and 52 kg/t U 15 transuranium nuclides /sup 237/Np to /sup 246/Cm have been determined by alpha and gamma spectroscopy after radiochemical separation.
Alpha-hemoglobin-stabilizing protein (AHSP) is an erythroid-specific protein that acts as a molecular chaperone for the free α chains of hemoglobin. Evidence strongly suggests...Full Text Available
The plerocercoid stage of the tapeworm Spirometra mansonoides produces a functional analog of human growth hormone (hGH). Among the similarities between plerocercoid growth factor (PGF) and hGH is competition for the same receptors on rabbit liver membranes. To take advantage of this characteristic in a purification scheme for PGF, rabbit liver microsomes were solubilized in Triton X-100 and the hGH receptors were purified over an hGH affinity column. The purified receptors from six rabbit livers were coupled to Affi-Gel-10 to create a receptor affinity column which was used to purify PGF. Chromatography of crude PGF over the receptor column resulted in a 1044 fold increase in specific activity. SDS-PAGE in the presence of 2-mercaptoethanol showed that the affinity-purified PGF contained three protein bands with apparent Mrs of 27.5 K, 22 K, and 16.7 K. Injections of the ...
(3H)Quinuclidinyl benzilate binding to rat brain muscarinic receptors decreased after repeated exposure to soman, a potent organophosphorus cholinesterase inhibitor. The topographical distribution of this decrement was analyzed by quantitative receptor autoradiography. After 4 weeks of soman, three times a week, quinuclidinyl benzilate binding decreased to 67 to 80% of control in frontal and parietal cortex, caudate-putamen, lateral septum, hippocampal body, dentate gyrus, superior colliculus, nucleus of the fifth nerve, and central grey. Minor or no decreases were observed in thalamic or hypothalamic nuclei, reticular formation, pontine nuclei, inferior colliculus, nucleus of the seventh nerve, and cerebellum. Scatchard analyses of saturation curves using frontal cortex sections from soman-treated rats revealed a decrease in maximal quinuclidinyl benzilate binding from that in control rats and a return toward control levels by 24 days without ...
[3H]Quinuclidinyl benzilate binding to rat brain muscarinic receptors decreased after repeated exposure to soman, a potent organophosphorus cholinesterase inhibitor. The topographical distribution of this decrement was analyzed by quantitative receptor autoradiography. After 4 weeks of soman, three times a week, quinuclidinyl benzilate binding decreased to 67 to 80% of control in frontal and parietal cortex, caudate-putamen, lateral septum, hippocampal body, dentate gyrus, superior colliculus, nucleus of the fifth nerve, and central grey. Minor or no decreases were observed in thalamic or hypothalamic nuclei, reticular formation, pontine nuclei, inferior colliculus, nucleus of the seventh nerve, and cerebellum. Scatchard analyses of saturation curves using frontal cortex sections from soman-treated rats revealed a decrease in maximal quinuclidinyl benzilate binding from that in control rats and a return toward control levels by 24 days without ...
Full text: The maturation of chicken forebrain is protracted and occurs well after synapse formation providing a good model for studying mechanisms of brain maturation. Using microslices from immature (10 day) and adult chicken forebrain prepared after decapitation, we have examined functional properties of NMDA and AMPA receptors by measuring agonist-induced uptake of "4"5Ca"2"+ . The rate and extent of NMDA induced "4"5Ca"2"+ accumulation decreased during maturation with no change in EC_5_0. The rate and extent of the AMPA induced response also decreased with a 60-fold increase in EC_5_0. However, the total NMDA receptor content did not change as indicated by 3 H-MK801 binding and NR1 immunoreactivity in P2 fractions. Similarly, there was no change in the B_m_a_x of "3H-AMPA, though there was a two-fold increase in K_D, and little or no change in the immunoreactivity in GluR1, 2, 2/3 or 4. These results suggest that it is the regulation of ...
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 peptides to three cell surface receptors: type A natriuretic peptide receptor (NPR-A), type B natriuretic peptide ...
Introduction: Development of agonist positron emission tomography (PET) radioligands for the 5-HT neurotransmitter system is an important target to enable the understanding of human 5-HT function in vivo. ["1"1C]CUMI-101, proposed as the first 5-HT_1_A receptor agonist PET ligand, has been reported to behave as a potent 5-HT_1_A agonist in a cellular system stably expressing human recombinant 5-HT_1_A receptors. In this study, we investigate the agonist properties of CUMI-101 in rat brain tissue. Methods: ["3"5S]-GTP#gamma#S binding studies were used to determine receptor function in HEK (human embryonic kidney) 293 cells transfected with human recombinant 5-HT_1_A receptors and in rat cortex and rat hippocampal tissue, following administration of CUMI-101 and standard 5-HT1A antagonists (5-HT, 5-CT and 8-OH-DPAT). Results: CUMI-101 behaved as an agonist at human recombinant 5-HT_1_A ...
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 ...
Multi-cation #alpha#-Sialon ceramics were prepared using mixtures of samarium with calcium, magnesium, yttrium and ytterbium, and compared with a pure Sm-Sialon of equivalent total stabilising cation composition. A ratio of 80eq% samarium to 20eq% of the second stabilising additive was used. Samples were fired at 1820 deg C and subsequently heat treated at 1450 deg C. XRD phase analysis showed that all additives resulted in greater #alpha#-Sialon stability, and that calcium was the most effective additive for the stabilisation of the #alpha#-Sialon phase. Copyright (1998) Australasian Ceramic Society
At the RIKEN-RAL Muon Facility, {mu}{sup -} to {alpha} sticking K{sub {beta}} X-rays were observed for the first time taking advantage of the pulsed beam structure. The precision of the present measurements was insufficient to distinguish between theoretical models, however the observed K{sub {beta}}/K{sub {alpha}} X-ray intensity ratio tends to be smaller than most of these theoretical predictions.
Alpha particle confinement is necessary for ignition of a D-T tokamak fusion plasma and for first wall protection. Due to high radiation backgrounds and temperatures, scintillators and semiconductor detectors may not be used to study alpha particles which are lost to the first wall during the D-T programs on JET and ITER. An alternative method of charged particle spectrometry capable of operation in these harsh environments, is proposed: it consists of thin foils of electrically isolated conductors with the flux of alpha particles determined by the positive current flowing from the foils. 2 refs., 3 figs.
Nucleosynthesis and energy production in stellar environments depend critically on nuclear reaction cross sections. Reactions induced by alpha particles are important in the helium burning stage of stars, novae, and supernovae events. They involve light to medium weight nuclei up to about Z=32, and center-of-mass energies up to about 20 MeV. We are working on a project to compile and evaluate cross section data for alpha-induced reactions. These data will eventually be used to derive #alpha#-nucleus potential parameters. (author)
The possibilities, advantages, and difficulties of determining nuclear matter densities by elastic scattering of alpha-particles are generally discussed. On the basis of particular experimental data - 104 MeV alpha-particle scattering from "4"0,"4"2,"4"4,"4"8Ca - a refined folded potential is introduced using a density-dependent alpha-nucleon-interaction and target nucleus densities described by Fourier-Bessel-series. Thereby, the total nucleon densities of these isotopes were determined with little model dependence. The resulting root-mean-square radii and density differences are compared with other experimental results obtained by different methods. (orig.).
Several examples of agonist-directed trafficking of receptor signalling at 5-HT2A and 5-HT2C receptors have been reported that involve independent downstream transduction pathways. We now report the functional selectivity of a series of chemically diverse agonists at human (h)5-HT2A, h5-HT2B and h5-HT2C-VSV by examining two related responses, the upstream activation of Gq/11 proteins in comparison with its associated cascade of calcium mobilisation. At the h5-HT2A receptor, d-lysergic acid diethylamide (LSD) and the antiparkinsonian agents lisuride, bromocriptine and pergolide exhibit a higher potency for Gq/11 activation than calcium release in contrast with all the other tested ligands such as 5-HT, mCPP and BW723C86, that show an opposite preference of signalling pathway. Comparable observations are made at h5-HT2B and h5-HT2C-VSV receptors, suggesting a similar mechanism of functional selectivity ...
The TTT diagrams describing the beta to alpha isothermal transformation have been made by isothermal dilatometry for pure uranium and 21 alloys based on chromium, silicon, molybdenum, iron, aluminium, zirconium. The thermal cycle preceeding the isothermal...
The influence of structure on mechanical properties in the course of tensile tests in a wide range of temperatures was studied, using the VT16 structure thermally strengthened (alpha+beta)-titanium alloy by way of example. It is ascertained that transition from ductile to brittle fracture at the temperature of -196 deg C is observed only in coarse-grain alloy having alpha-eldging of beta grains.
Immobilization of long-lived fission products (LLFP) such as radioactive Tc, Cs and Sr into #alpha#-SiAlON ceramics was evaluated using stable isotopes instead of radioactive isotopes, and the applicability of #alpha#-SiAlON ceramics as the inert matrix for transmutation of LLFP was investigated. In the case of single addition of SrO, SrCO_3, Cs_2CO_3 or ReO_2 to the starting materials, #alpha#-SiAlON, single phase was not formed after hot-pressing. When Y_2O_3 was added with SrO, SrCO_3 or Cs_2CO_3 to the starting materials (#alpha#-Si_3N_4, AlN and #alpha#-Al_2O_3) in optimum compositions, #alpha#-SiAlON single phase was obtained after hot-pressing at 1700degC or 1800degC. From the EDS analysis, Sr and Y were detected from grains. It is suggested that Y would assist the expansion of interstices of #alpha#-SiAlON lattice, resulting in the ...
Mutations in transcription factors hepatocyte nuclear factors (HNF)-1#alpha# and HNF-1#beta# cause maturity-onset diabetes of the young (MODY) types 3 and 5, respectively. HNF-1#alpha# and HNF-1#beta# mutations are well studied in some tissues, but the mechanism by which HNF-1#alpha# and HNF-1#beta# mutations affect sucrase-isomaltase (SI) transcription in the small intestine is unclear. We studied the effects of 13 HNF-1#alpha# mutants and 2 HNF-1#beta# mutants on human SI gene transcription, which were identified in subjects with MODY3 and MODY5, respectively. Transactivation activity of 11 HNF-1#alpha# and 2 HNF-1#beta# mutants was significantly lower than that of wild (wt)-HNF-1#alpha# and wt-HNF-1#beta#. Furthermore, in co-expression studies with mutant (mu)-HNF-1#alpha#/ wt-HNF-1#beta# and ...
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: ...
Somatostatin receptor scintigraphy (SRS) is a valuable method for the detection of somatostatin receptor-positive lesions. Most gastrinomas (over-)express the somatostatin receptor subtype 2 which can be targeted by In-111 labeled Octreotide. Different studies show a high sensitivity of SRS for the localization and staging of gastrinomas. SRS seems to be superior to other non-invasive imaging modalities and has been proven to significantly contribute to patient management. However, the sensitivity depends on the size and exact localization of the tumors. Smaller lesions and lesions located in the duodenum show a significantly lower sensitivity. In any case, SRS belongs to the routine imaging procedure for gastrinomas for localization and staging and can also be used for evaluation of the tumor progression. (author)
Keratinocyte growth factor receptor (KGFR) and fibroblast growth factor receptor (FGFR) 2c share identical amino acid sequences, except for a 46-amino acid domain in the extracellular region. Monoclonal antibodies (MAbs) specific to KGFR have not been reported nor are commercially available. In this study, we generated murine MAbs specific to KGFR in non-obese diabetic (NOD) mice using a modified Repeated Immunizations at Multiple Sites (RIMMS) technology. Stable cell lines expressing the full-length human KGFR or FGFR2c were produced to facilitate the identification of KGFR-specific MAbs. Following the initial screening of hybridoma clones with a fluorescence-based, confocal cell detection method and ELISA, KGFR-specific MAbs were selected and confirmed by flow cytometry and Western blot ...
We develop the formalism of a unified semi-microscopic description of low-energy proton and {alpha}-particle interaction with nuclei. We analyze elastic and inelastic proton scattering at the energy 25.05 MeV and {alpha}-particle scattering at the energy 104 MeV by the {sup 90}Zr nucleus. Information is obtained on differences in the deformation of the proton and neutron distributions. We study the energy dependence of the semi-microscopic {alpha}-particle potential including the energy dependence of the potential geometry.'' We analyze the change in angular distributions of elastically scattered {alpha} particles with increase of energy and the contribution to the scattering cross section from nucleon-nucleon correlations.
The neutron transition multipole moment, M/sub n/, for (0/sup +/..-->..2/sup +/, 1.84 MeV) transition is inferred by measuring the (..cap alpha..,..cap alpha..') angular distribution at E/sub ..cap alpha../ = 50 MeV and comparing it with a microscopic distorted-wave Born approximation calculation. Proton transition densities are taken from electron scattering data. M/sub n//M/sub p/ is found to be substantially less than N/Z in agreement with the (p,p') result.
Proton and alpha decay from the giant resonance region of {sup 28}Si excited with a 129 MeV alpha particle beam has been measured in coincidence with inelastic alpha particles detected at 0{degree}. The angular correlation data show the presence of decay from both {ital E}0 and {ital E}2 giant resonances. The {ital E}0 giant resonance decays primarily through the {alpha}{sub 0}, {alpha}{sub 1}, {ital p}{sub 0}, and {ital p}{sub 1,2} channels with the branching ratios 18{plus minus}6 %, 24{plus minus}8 %, 23{plus minus}9 %, and 18{plus minus}8 %, respectively. Substantial direct decay is observed.
Comparisons of calculated neutron yield distributions from #alpha#-particle induced reactions on thick targets are made with measured data to analyze the initial reaction process in the framework of the exciton (hybrid) model code ALICE91 (M. Blann, Lawrence Livermore National Laboratory Report UCID 19614, 1982). We have considered two reaction mechanisms: dissolution of the #alpha# in the nuclear field, and preequilibrium processes initiated by #alpha#-nucleon collisions. Both these processes seem to contribute to the emitted neutron spectra in varying proportions depending on the incident #alpha# energy and possibly on the target nucleus. Contributions from other processes appear to be non-negligible.
Differential cross sections of the (#alpha#, t) reactions on "4"5Sc, "5"1V, and "5"9Co nuclei are measured in the 10-71 deg, 10-155 deg, and 10-171 deg angular ranges, respectively, with 27.2 MeV alpha particles. The cross sections have also been calculated on the basis of the distorted wave theory. The possibility of an unambiguous choice of the optical potential for alpha particles is discussed. The angular distribution calculations using several combinations of the optical potentials in the inlet and outlet channels of the reactions show that consistence between the calculations and the measurements is achieved (especially in angular range, less than 90 deg, if one of the potentials is chosen to be a sufficiently deep one.
"2"7Al and "2"9Si solid-state NMR spectra and X-ray diffraction (XRD) patterns were obtained for #alpha#-SiAlON powders prepared by combustion synthesis, according to which the phase transformation and structure evolution of #alpha#-SiAlON were studied. It was found that in #alpha#-SiAlON "2"9Si chemical shift values (-48 < #delta# _S_i < -47) were close to those in #beta#-Si_3N_4 and #alpha#-Si_3N_4, indicating that Si atoms kept SiN_4 coordination to a large extent in #alpha#-SiAlON despite the presence of O atoms. Dissimilarly, "2"7Al chemical shift values in #alpha#-SiAlON deviated clearly from that corresponding to AlN_4 coordination (#delta# _A_l #approx# 112) and occurred in a range from #delta# _A_l 95.5 to 99.9, which should be assigned to tetrahedral AlO _xN_4_-_x (0 #<=# x #<=# 4) coordination. The broadening effect of AlO _xN_4_-_x peaks ...
Using conventional deep level transient spectroscopy (DLTS), we have characterized the defects introduced in OMVPE n-GaAs at 15 K by 5.4 MeV alpha particle irradiation from an americium 241 radio-nuclide. After this low temperature irradiation two new defects not yet reported for alpha irradiated GaAs before, E[alpha]7 and E[alpha]9, were detected 0.07 eV and 0.19 eV below the conduction band, respectively. The introduction rates of E[alpha]7 and E[alpha]9 are calculated to be 41 cm[sup -1] and 187 cm[sup -1] respectively. It was observed that both defects obeyed first order annealing kinetics, with E[alpha]9 being removed at 225 K and E[alpha]7 at 245 K corresponding to the well known stage I annealing region. The annealing rate of E[alpha]7 corresponds to an activation energy of 0.86 eV, with a ...
The mechanisms that contribute to the extinction of previously acquired memories are not well understood. These processes, often referred to as inhibitory learning, are thought to be parallel...Full Text Available
Transient receptor potential (TRP) ion channels have been implicated in detecting chemical, thermal and mechanical stimuli in organisms ranging from mammals to Caenorhabditis elegans....Full Text Available
BackgroundGreen tea consumption has been shown to have cancer preventive qualities. Among the constituents of green tea, (-)-Epigallocatechin-3-O-gallate (EGCG)...Full Text Available
Receptor protein tyrosine phosphatase T (PTPRT/PTPρ) is frequently mutated in human cancers including colon, lung, gastric and skin cancers. More than half of the identified tumor-derived...Full Text Available
BackgroundThe dynorphin-kappa opioid receptor (KOR) system regulates glial proliferation after sciatic nerve injury. Here, we investigated its role in cell proliferation following...Full Text Available
Experience-dependent plastic changes in the central sensory systems are due to activation of both the sensory and neuromodulatory systems. Nonspecific changes of cortical auditory neurons elicited by...Full Text Available
Recent research has implicated the nucleus accumbens (NAc) in consolidating recently acquired goal-directed appetitive memories, including spatial learning and other instrumental processes. However,...Full Text Available
Cervical spinal cord hemisection rostral to the phrenic nucleus leads to paralysis of the ipsilateral hemidiaphragm in adult rats. Respiratory function can be restored to the paralyzed hemidiaphragm...Full Text Available
Studies in rodents have shown that male sexual function can be disrupted by fetal or neonatal administration of compounds that alter endocrine homeostasis, such as the synthetic nonsteroidal estrogen...Full Text Available
AimsIt is unclear as to which mediators are involved in mediating the response to nasal mannitol challenge, a novel osmotic stimulus.MethodsA...Full Text Available
BackgroundNFκB signaling is of paramount importance in the regulation of apoptosis, proliferation, and inflammatory responses during human development and homeostasis, as...Full Text Available
The C-C chemokine receptor 5, 32 base-pair deletion (CCR5-Δ32) allele confers strong resistance to infection by the AIDS virus HIV. Previous studies have suggested...Full Text Available
SummaryTRPV1 is the founding and best-studied member of the family of temperature-activated transient receptor potential ion channels (thermoTRPs). Voltage, chemicals, and heat...Full Text Available
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
The synthesis and structure-activity relationship analysis of a novel class of amide-based biaryl NR2B-selective NMDA receptor antagonists are presented. Some of the studied compounds are potent, selective, non-competitive, and voltage-independent antagonists of NR2B-containing NMDA receptors. Like the founding member of this class of antagonists (ifenprodil), several interesting compounds of the series bind to the amino terminal domain of the NR2B subunit to inhibit function. Analogue potency is modulated by linker length, flexibility, and hydrogen bonding opportunities. However, unlike previously described classes of NR2B-selective NMDA antagonists that exhibit off-target activity at a variety of monoamine receptors, the compounds described herein show much diminished effects against the...
Understanding the mechanisms whereby information encoded within patterns of action potentials is deciphered by neurons is central to cognitive psychology. The multiprotein complexes formed by...Full Text Available
Gonadal, adrenal, and thyroid hormones affect the brain directly, and the sensitivity to hormones begins in embryonic life with the appearance of hormone receptor sites in discrete populations of neurons....Full Text Available
Somatostatin receptor expression has been demonstrated on a number of plasma cell lines. Therefore, we questioned whether somatostatin receptor scintigraphy (SRS) can be used to demonstrate in vivo multiple myeloma (MM) activity. SRS was performed in newly diagnosed (n = 9) or relapsing (n = 18) MM patients or in patients with localized plasmacytoma (n = 2). The results were compared with radiographic findings. A positive SRS was demonstrated in 44% of the newly diagnosed patients, in 83% of the relapsed patients and in both patients with plasmacytoma. The SRS findings corresponded with radiographic abnormalities in 40% of the patients. However, in relapsed patients 60% demonstrated increased SRS uptake in areas without new radiographic abnormalities. The positive SRS corresponded with histologically proven disease activity and responded upon treatment. Moreover, immunohistochemical staining of MM material demonstrated concordant somatostatin ...
BackgroundPostoperative delirium is a topic of great importance in the geriatric surgical specialty. Although antipsychotic drugs are the medications most frequently used to treat...Full Text Available
Receptor activator of NF-kB ligand (RANKL) and osteoprotegerin (OPG) play key roles in the pathogenesis of glucocorticoid-induced osteoporosis (GIO). The aim of our study was to determine whether the...Full Text Available
Human epidermal growth factor receptor 2 (HER2) is one of the most important prognostic and predictive factors for breast cancer patients. Recently, serum HER2...Full Text Available
The goal of ultrasonic molecular imaging is the detection of targeted contrast agents bound to receptors on endothelial cells. We propose imaging methods that can distinguish adherent microbubbles...Full Text Available
Background:Endothelin-1 may be involved in the development of diabetic microangiopathy. We studied the effect of endothelin-1 blockade on myocardial microcirculation during coronary...Full Text Available
Rejection of eight aldehydes, eight ketones, five secondary alcohols, and 3-pentanol has been studied in the blowfly Phormia regina Meigen. The data agree with results previously reported...Full Text Available
The effect of A1-adenosine receptor antagonism via 8-cyclopentyl-1,3-dipropyl-xanthine (CPDPX) on the stimulation of skeletal muscle glucose uptake by...Full Text Available
PurposeIn our previous studies we showed that upregulating claudin-6 (CLDN6) expression may contribute to preventing breast cancer, and that 17β-estradiol induces a concentration-...Full Text Available
A statistical method is developed to determine the locations of major pollutant sources affecting a distant downwind receptor, provided that air trajectories can be estimated. Probability density functions are estimated which indicate the overall residence time of air parcels over a given geographic region as they travel toward a receptor and residence time for the case of high pollutant concentrations at the receptor. These functions are used to estimate a conditional probability function which indicates the potential for a source region to contribute to high air pollution concentrations. Finally, a source contribution function is formulated to indicate the relative contribution of different source regions to high concentrations at the receptor. The method is tested using data collected at Grand Canyon National Park in 1980. The dominant pathway for air masses arriving at Grand Canyon during this ...
Targeted studies completed include the evaluation of tritiated N-0437, evaluation of "3"5S-cysteamine, evaluation of "1"8F-FDG and initiation of synthetic efforts towards the synthesis of iodinated N-0437 and pergolide analogs. The direction of the project has been changed due to several factors which include the decided lack of favorable experimental results, the excellence of results using muscarinic receptor ligands in pituitary, brain and heart and the contention of the DOE review panel that the original grant proposal was based on flawed assumptions together with their perceived lack of importance to pituitary imaging. In the final year of this grant, three studies will be completed. The first study is the continuation of synthetic efforts to prepare iodinated N-0437 and pergolide analogs for possible use as brain imaging agents. The second study is directed towards completion of biochemical evaluation of various muscarinic receptor ...
Targeted studies completed include the evaluation of tritiated N-0437, evaluation of /sup 35/S-cysteamine, evaluation of /sup 18/F-FDG and initiation of synthetic efforts towards the synthesis of iodinated N-0437 and pergolide analogs. The direction of the project has been changed due to several factors which include the decided lack of favorable experimental results, the excellence of results using muscarinic receptor ligands in pituitary, brain and heart and the contention of the DOE review panel that the original grant proposal was based on flawed assumptions together with their perceived lack of importance to pituitary imaging. In the final year of this grant, three studies will be completed. The first study is the continuation of synthetic efforts to prepare iodinated N-0437 and pergolide analogs for possible use as brain imaging agents. The second study is directed towards completion of biochemical evaluation of various muscarinic ...
In this study we compared the molecular signalling elicited by rexinoids, selective retinoid X receptor (RXR)-activators, in several organs (i.e. liver, kidney,...Full Text Available
BackgroundGlucocorticoids down-regulate cytokine synthesis and suppress inflammatory responses. The glucocorticoid receptor (GR) antagonist RU486 may exacerbate the inflammatory...Full Text Available
Breast cancer is a progressive and potentially fatal disease that affects women of all ages. Like all progressive diseases, early and reliable diagnosis is the key for successful treatment and annihilation....Full Text Available
BackgroundThe lactogenic hormones prolactin (PRL) and placental lactogens (PL) play central roles in reproduction and mammary development. Their actions are mediated via binding...Full Text Available
Cervical cancer is known to metastasize primarily by the lymphatic system. Dissemination through lymphatic vessels represents an early step in regional tumor progression, and the presence of lymphatic...Full Text Available
Hypoxia, or reduced oxygen, occurs in a variety of clinical and environmental situations. Hypoxic exposure is associated with decreased muscle mass and a concomitant reduction in exercise capacity,...Full Text Available
Cleavage of membrane-associated proteins with the release of biologically active macromolecules is an emerging theme in biology. However, little is known about the nature and regulation of the involved...Full Text Available
Although the mechanism is unknown, Calculus Bovis and its active components, cholic acid analogs (CAAs), have been used in China to treat a wide range of diseases. Based on the previous finding that the potency of CAA is strongly dependent on the intrinsic surface activity, this paper aimed to investigate the role of the plasma membrane in the pharmacological activity of CAAs. First, CAAs (0.1 mM) caused a surface activity-dependent depression on ATPase activity in the cell membrane extract, but it had no effects on other cellular extracts, suggesting an indispensable role of the membrane environment for pharmacological activity. Second, CAAs lowered the membrane fluidity of cultured Caco-2 cells with the same rank-order of potency sequence. Third, the hypothesis that any functional protein located on the membrane is influenced by changes in cellular membrane fluidity was supported by: ileal contraction that was induced by acetylcholine and mediated by the muscarinic ...
BackgroundZibotentan (ZD4054) is a specific endothelin A (ETA) receptor antagonist being investigated for the treatment of prostate cancer. As zibotentan is eliminated...Full Text Available
Idiopathic pulmonary fibrosis (IPF) is a progressive disease with poor survival. The identification of therapeutic targets is essential to improving outcomes. Previous studies found that expression...Full Text Available
Acute inflammation is important for tissue repair; however, chronic inflammation contributes to neurodegeneration in Alzheimer’s disease (AD) and occurs when glial cells undergo prolonged...Full Text Available
IntroductionIn the last few years, various studies have underlined a correlation between thyroid function and male sexual function, hypothesizing a direct action of thyroid hormones...Full Text Available
Macrophage activation by the proinflammatory cytokine interferon-γ (IFN-γ) is a critical component of the host innate response to bacterial pathogenesis. However, the precise nature...Full Text Available
Nicotine is the main psychoactive ingredient in tobacco and its rewarding effects are considered primarily responsible for persistent tobacco smoking and relapse. Although dopamine has been extensively...Full Text Available
Women experience a decline in estrogen and androgen levels after natural or surgically induced menopause, effects that are associated with a loss of sexual desire and bone mineral density. Studies in...Full Text Available
The effects of paeoniflorin (PF), a compound isolated from Paeony radix, on neurological impairment and histologically measured infarction volume...Full Text Available
The CNS can exhibit features of inflammation in response to injury, infection or disease, whereby resident cells generate inflammatory mediators, including cytokines, prostaglandins, free radicals and...Full Text Available
Hypoxia–ischemia (H/I) in the premature infant leads to white matter injury termed periventricular leukomalacia (PVL), the leading cause of subsequent neurological deficits. Glutamatergic...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
The X-ray crystallographic structural determinations of synthetic estrogens and antiestrogens provide reliable information on the global minimum energy conformation of these molecules or a local minimum...Full Text Available
Cytoadherence or sequestration is essential for the pathogenesis of the most virulent human malaria species, Plasmodium falciparum (P. falciparum). Similar to leukocyte-endothelium...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
Antibodies to myelin oligodendrocyte glycoprotein (MOG) have been implicated in Multiple Sclerosis demyelination through activation of complement and/or macrophage-effector processes. We presented...Full Text Available
We had previously identified a macrophage surface protein whose expression is highly induced, transient, and specific, as it is restricted to actively fusing macrophages in vitro and in vivo. This protein...Full Text Available
A growing number of studies suggest that the development of compulsive drug seeking and taking depends on dorsostriatal mechanisms. We previously observed that ex vivo acute...Full Text Available
In addition to its role in megakaryocyte production, signaling initiated by thrombopoietin (TPO) activation of its receptor, myeloproliferative leukemia virus protooncogene (c-Mpl, or Mpl), controls...Full Text Available
Host cells use metabolic signaling through the LXRα nuclear receptor to defend against Listeria monocytogenes infection. 25-Hydroxycholesterol is a natural ligand of LXRs that...Full Text Available
Disruption of circadian rhythms may be involved in the pathophysiology of psychiatric disorders, including drug addiction. Recently, we detected the significant association between prokineticin 2 receptor...Full Text Available
Hematopoiesis is the cumulative result of intricately regulated signaling pathways that are mediated by cytokines and their receptors. Studies conducted over the past 10 to 15 years have revealed that...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
BackgroundThe VP2 outer capsid protein Bluetongue Virus (BTV) is responsible for receptor binding, haemagglutination and eliciting host-specific immunity. However, the assembly of...Full Text Available
Sensory experience plays a crucial role in regulating neuronal shape and in developing synaptic contacts during brain formation. These features are required for a neuron to receive, integrate, and transmit...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 endothelin-B (ETB) receptor is a G-protein-coupled receptor that binds endothelin ligands and is essential for the development of epidermal melanocytes and enteric neurons. Recent reports indicate that ETB is localized to nuclei in cardiac ventricular myocytes, although it has been thought that ETB is localized mainly on the plasma membrane. It remains unknown, however, whether this unique distribution of ETB occurs in other tissues. To elucidate the subcellular distribution of ETB in the intestine, we performed immunofluorescence of ETB in mouse intestine using a specific antibody. ETB-like immunoreactivity was detected in both the mucosal and muscle layers. In the mucosal layer, villous epithelial cells, stromal cells of the lamina propria, and cryptic cells were immunostained. Subcellularly, ETB is localized mainly to the nuclei of villous epithelial cells. In the muscle layer, immunoreactivity of ETB was localized to the myenteric ...
Neuropilin-1 (NRP1) acts as a co-receptor for class 3 semaphorins and vascular endothelial growth factor and is an attractive angiogenesis target for cancer therapy. In addition to the transmembrane...Full Text Available
Bacillus thuringiensis subsp. israelensis, which is used worldwide to control Aedes aegypti larvae, produces Cry11Aa and other toxins during...Full Text Available
This study addresses the mechanism of transport of the H2-receptor antagonist, cimetidine, by the human placenta. A 4-h recycling perfusion of a single placental cotyledon of normal, term, human placenta...Full Text Available
Histamine has been proposed to be an important regulator of energy intake and expenditure. The aim of this study was to evaluate histamine regulation of glucose and lipid metabolism and development...Full Text Available
Recently, we demonstrated that the central ghrelin signalling system, involving the ghrelin receptor (GHS-R1A), is important for alcohol reinforcement. Ghrelin targets a key mesolimbic circuit involved...Full Text Available
Place fields of hippocampal pyramidal cells expand asymmetrically when adult rats repeatedly follow the same route. This behaviorally-induced expression of neuronal plasticity utilizes an NMDAR-dependent,...Full Text Available
The genetic basis of odorant-specific variations in human olfactory thresholds, and in particular of enhanced odorant sensitivity (hyperosmia), remains largely unknown. Olfactory receptor (OR) segregating...Full Text Available
The role of pheromone biosynthesis activating neuropeptide (PBAN) in the regulation of pheromone biosynthesis of several female moth species is well elucidated, but its role in the males has been a...Full Text Available
Exteriorized phosphatidylserine (PS) residues in apoptotic cells trigger rapid phagocytosis by macrophage scavenger receptor pathways. Mimicking apoptosis with liposomes containing PS may represent...Full Text Available
Dectin-1, the major β-glucan receptor in leukocytes, triggers an effective immune response upon fungal recognition. Here we use sortase-mediated transpeptidation, a technique that allows placement...Full Text Available
Tamoxifen (TAM) is a selective estrogen receptor modulator widely used in the prevention and treatment of breast cancer. A major mode of metabolism of the major active metabolites of TAM, 4-OH-TAM...Full Text Available
Fibroblast growth factor (FGF) signaling is involved in skeletal development of the vertebrate. Gain-of-function mutations of FGF receptors (FGFR) cause craniosynostosis, premature fusion of the skull,...Full Text Available
BackgroundLeukotrienes (LTs) belong to the large family of lipid mediators implicated in various inflammatory conditions such as asthma and rheumatoid arthritis. Four distinct types...Full Text Available
SUMMARYMotile dendritic filopodial processes are thought to be precursors of spine synapses, but how motility relates to cell-surface cues required for axon-dendrite recognition...Full Text Available
Protective innate immunity to the nematode Strongyloides stercoralis requires eosinophils in the parasite killing process. Experiments were performed to determine if an extract of S....Full Text Available
BackgroundThiazolidinediones (TZDs) activate peroxisome proliferator-activated receptor gamma (PPARγ) and are used clinically to help restore peripheral insulin sensitivity...Full Text Available
Porphyromonas gingivalis has been implicated as a causative pathogen in periodontitis. Immunotherapeutic approaches have recently been suggested to aid in the clearance of P....Full Text Available
The specific receptor sites and the endocytosis of transferrin (Tf) are evidenced in a cell line (HT-29) derived from a human colic adenocarcinoma by means of "1"2"5I radiolabeled Tf. The receptor density is studied in undifferentiated (UD) or differentiated (D) cells with respective doubling times of about 24 hours and 46 hours. The number of binding sites for Tf is 162,000 (K_d = 7.8 nmol/l in ND cells and 68,000 (K_d = 7.40 nmol/l) in D cells. The distribution between the Tf bound to the cell surface and the internalized Tf is investigated by elimination of Tf bound to the surface by an acid wash method. The intracellular cycle of Tf seems to be characterized by a slower kinetics in UD cells. The high density of Tf receptor sites in HT-29 UD cells should allow the detection or the treatment of highly evolutive colic adenocarcinoma by means of Tf.
Objective:To investigate the combined effect of both pioglitazone and methotrexate on disease activity of rheumatoid arthritis in a biphasic study; experimental and clinical.Methods:Experimentally:...Full Text Available
B lymphocytes can function independently as efficient APCs. However, our previous studies demonstrate that both dendritic cells and macrophages are necessary to propagate immune responses initiated...Full Text Available
Glioblastoma, the most common malignant brain tumor, is among the most lethal and difficult cancers to treat. Although epidermal growth factor receptor (EGFR) mutations are frequent in glioblastoma,...Full Text Available
BackgroundThe N-methyl-D-aspartate (NMDA)-type glutamate receptor expressed at excitatory glutamatergic synapses is required for learning and memory and is critical for normal brain...Full Text Available
Retinoic acid inducible gene I (RIG-I) is a pattern recognition receptor (PRR) responsible for detection of nucleic acids from pathogens in the cytoplasm of infected cells and induction of type I interferon...Full Text Available
SummaryHuman skin expresses elements of the hypothalamo-pituitary-adrenal (HPA) axis including pro-opiomelanocortin (POMC), corticotropin releasing hormone (CRH), the CRH receptor-1...Full Text Available
We investigated the effects of PSARK∷IPT (for Senescence-Associated Receptor Kinase∷Isopentenyltransferase) expression and cytokinin production...Full Text Available
Cyclophilins (Cyps), the intracellular receptors for Cyclosporine A (CsA), are responsible for peptidyl-prolyl cis-trans isomerisation and for chaperoning several membrane proteins. Those functions...Full Text Available
BackgroundMost rapidly evolving gene families are involved in immune responses and reproduction, two biological functions which have been assigned to the carcinoembryonic antigen...Full Text Available
Mechanisms regulating sexual differentiation of the zebra finch song system appear to include both genetic and hormonal factors. Sorting Nexin 2 (SNX2), which is involved in trafficking proteins...Full Text Available
We presented data showing that the CART-19 cells expressing the 4-1BB signaling domain can have unprecedented and massive in-vivo expansion, traffic to tumor sites, persist long term in vivo, and induce...Full Text Available
Cytokinins are distributed through the vascular system and trigger responses of target cells via receptor-mediated signal transduction. Perception and transduction of the signal can occur at the plasma...Full Text Available
Cd36 is a small-molecular-weight integral membrane protein expressed in a diverse, but select, range of cell types. It has an equally diverse range of ligands and physiological functions, which has...Full Text Available
Klebsiella pneumoniae is able to grow anaerobically with citrate as a sole carbon and energy source by a fermentative pathway involving the Na+-dependent citrate...Full Text Available
Benzodiazepine withdrawal anxiety is associated with potentiation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptor (AMPAR) currents in hippocampal CA1 pyramidal...Full Text Available
Calcium, vitamin D, exposure to sunshine, and vitamin D receptor (VDR) genotypes have been associated rectal cancer. We used data from 750 rectal tumors and 1,205 population-based...Full Text Available
Recent evidence suggests a role for corticotropin-releasing factor (CRF) in the regulation of pair bonding in prairie voles. We have previously shown that monogamous and non-monogamous vole...Full Text Available
The pharynx is the primary reservoir for strains of group A Streptococcus (GAS) associated both with pharyngitis (streptococcal sore throat) and with invasive or “flesh-eating”...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
Bacterial pathogens use virulence strategies to invade epithelial barriers, but active processes of epithelial cells may also contribute to the endocytosis of microbial particles. To focus on the latter,...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
Experimental studies have demonstrated that not only dopaminergic signaling but also glutamatergic/NMDA receptor signaling play indispensable roles in the development of methamphetamine psychosis. Our...Full Text Available
Pharmacologic or genetic deletion of components of the renin-angiotensin system leads to postnatal kidney injury, but the roles of these components in kidney development are unknown. To test the hypothesis...Full Text Available
Numerous xenobiotics, including therapeutics agents, are substrates for bioactivation to electrophilic reactive intermediates that may covalently modify biomolecules. Selective estrogen receptor...Full Text Available
BackgroundMale infertility is a common cause of reproductive failure in humans. In mice, targeted deletions of the genes coding for FKBP6 or FKBP52, members of the FK506 binding...Full Text Available
We sought to determine the effects of activation of peroxisome proliferator-activated receptor-γ (PPAR-γ) on multilocularization of adipocytes in adult white adipose tissue (WAT). Male...Full Text Available
Endogenous immune complexes present in sera from 10 different patients with systemic lupus erythematosus (SLE) in an active phase were allowed to bind to Raji cells; the ability of intact complement...Full Text Available
BackgroundCentrosome aberrations can cause genomic instability and correlate with malignant progression in common human malignancies such as breast and prostate cancer. Deregulation...Full Text Available
The ventromedial hypothalamus (VMH) plays a central role in the regulation of the female reproductive behavior lordosis, a behavior dependent upon the sequential activation of receptors for the ovarian...Full Text Available
ObjectiveThe goal of the study was to investigate the genetic and molecular basis of a novel syndrome of marked hyperglucagonemia and pancreatic α cell hyperplasia...Full Text Available
BackgroundThis in vitro study was conducted to compare the accuracy of two digital image receptors in identifying the location of tip of a fine endodontic file and radiographic apex...Full Text Available
Abstract: Snake venom contains a number of small proteins,enzymes and other components,which displays a broad spectrum of biological activities. With the ability of specifically binding on acetylcholine acceptor, alpha-bungarotoxins are not only useful molecular probes in investigating the mechanism of neural signal transmission, but also potential pharmic preparations for neural disease treatment. In current research,cDNAs of Bungarus multicinutus venom gland were synthesized using SMART cDNA amplification kit and then, alpha-bungarotoxin genes were cloned and sequenced. Total of 20 clones were sequenced representing 14 isotoxin mRNAs of alpha-bungarotoxins. Among those clones, a novel isotoxin gene was subcloned into two expression plasmids, alpha-BgTX/pQE30a and alpha-BgTX/pGEX-4T-1, and transformed into E. coli. After inducing with IPTG, fused protein of ...
Tumor necrosis factor alpha (TNF-alpha) and interleukin-1 (IL-1) have been shown to stimulate bone resorption in vitro. We have now investigated whether these cytokines also cause a similar action when administered in vivo. This was made possible by the adaptation of a newly developed technique that enables the continual assessment of bone resorption in vivo in mice by measuring urinary excretion of {sup 3}H from ({sup 3}H)tetracycline-prelabeled animals. Experiments using maneuvers known to influence bone resorption, such as a change in dietary calcium or administration of parathyroid hormone or dichloromethylenebisphosphonate, indicate that the technique is reliable and sensitive in mice. Daily intravenous administration of either recombinant human or recombinant murine TNF-alpha, as well as subcutaneous administration of recombinant human IL-1 alpha, were found to stimulate bone resorption in a ...
The possibility of having Sr as an interstitial metal cation in #alpha#-SiAlON has been investigated in two systems: a single-cation system (Si_3N_4-SrO-AlN) and a multication system (Si_3N_4-(Y_2O_3/SrO/CaO)-AlN). It was found that Sr alone does not form #alpha#-SiAlON and that Sr could only be accommodated in #alpha#-SiAlON in conjunction with Y and Ca. The Sr content of #alpha#-SiAlON increased as the total content of (Y + Ca) increased and appeared to reach a limit at 0.5 at.%, or 0.15 atom per #alpha#-SiAlON. Unexpectedly, some of the #alpha#-SiAlON that contained (Sr + Y + Ca) was present as laths or fibers with the c-axis perpendicular to the hot-press direction.
The densification of #alpha#"1-and #alpha#"+#beta#"1-sialon ceramics has been studied by means of in situ dilatometry. It is seen that the densification is greatly affected by the reaction sequences and the grain growth. The formation and densification of sialons start simultaneously as the dissolution of nitrides into the oxide eutectic liquid phase occurs. The formation of sialons is complete at 1800 deg C., while full densification can only be obtained by using gas pressure sintering. The typical microstructure of both #alpha#"'-and mixed #alpha#'+#beta#'-sialon ceramics consists of a crystalline phase of sialons and a small fraction of amorphous phase at grain boundaries. Vickers hardness (HV0.5) was measured by using the indentation technique, and the biaxial bending strength (#sigma#_b_i) was determined with the 'ball-on-ring' test. Fracture toughness was determined by using both the indentation ...
Rare earth stabilised #alpha#-SiAlONs are commonly observed with an equiaxed grain morphology. Elongated #alpha#-SiAlON has been observed in some of these systems, however it usually results from special techniques such as pressure sintering. The formation of elongated #alpha#-SiAlON grains during pressureless sintering has been shown to commonly occur in the Ca #alpha#-SiAlON system. Examination of phase and microstructural development in three Ca #alpha#-SiAlON compositions in the temperature range 1400 deg to 1800 deg C showed that phase development and grain growth occurred at different temperatures. It was found that chemical reactions were completed by 1550 deg C, however significant grain growth did not occur at this temperature. Grain growth progressed from 1600 deg C and continued up to 1800 deg C, the maximum temperature investigated. At 1800 deg C, ...
The traditional view that Ly-alpha emission and dust should be mutually exclusive has been questioned more and more often, notably the observations of Ly-alpha emission from ULIRGs seems to counter this view. In this paper we seek to address the reverse question: How large a fraction of Ly-alpha selected galaxies are ULIRGs? Using two samples of 24/25 Ly-alpha emitting galaxies at z = 0.3/2.3 we perform this test, also including results at z = 3.1, and find that whereas the ULIRG fraction at z = 3.1 is very small, it systematically increases towards lower redshifts. There is a hint that this evolution may be quite sudden and that it happens around a redshift of z ~ 2.5. Measuring the infrared luminosities of the Ly-alpha emitters, we find that they are in the normal to ULIRG range in the lower redshift sample, whereas the higher redshift galaxies all have luminosities in the ULIRG ...
We construct a sample of low-redshift Ly-alpha emission-line selected sources from GALEX grism spectroscopy of nine deep fields to study the role of Ly-alpha emission in galaxy populations with cosmic time. Our final sample consists of 122 (142) sources selected in the redshift interval z=0.195-0.44 (z=0.65-1.25) from the FUV (NUV) channel. We classify the Ly-alpha sources as AGNs if high-ionization emission lines are present in their UV spectra and as galaxies otherwise. These classifications are broadly supported by comparisons with X-ray and optical spectroscopic observations. We classify additional sources as AGNs using line widths for our Ly-alpha emitter (LAE) analysis. Defining the GALEX LAE sample in the same way as high-redshift LAE samples, we show that LAEs constitute only about 5% of NUV-continuum selected galaxies at z~0.3. We also show that they are less common at z~0.3 than they are at ...
Obtained experimental data on integral cross sections (ICS) of inelastic scattering of 50.5 MeV #alpha# particles with the excitation of "6","7Li, "9Be, "1"2","1"3C, "1"4C, "1"4N, "2"0Ne, "2"4Mg, "2"8Si nucleus low-lying energy levels are discussed. Regularities, detected in the behaviour of ICS forward scattering for 20-90 deg angles and backscattering for 90-160 deg angles for the target-nucleus under investigation are considered. Effect of reaction open channel number on #alpha#-particle scattering ICS where n,p,d- and #alpha#-channels were considered as the main channels for all the target-nuclei, is discussed. Dependence of #alpha#-particle scattering ICS on the target-nucleus level excitation energy and dependences of reaction open channel number on the channel spin, calculated for 50.5 MeV #alpha# particles and different target nuclei are shown in the diagrams. It is noted ...
A technique has been developed for high resolution alpha particle spectroscopy from track length determination in CR-39 plastic. On individual tracks an energy resolution deltaE close to the range straggling limit is obtainable. For 6 MeV alpha-particle deltaE is proportional 35 keV on individual particles and for groups of particles deltaE proportional 20 keV can be achieved using certain data selection criteria. At 100 keV on individual particles deltaE is proportional 20 keV. The analysis requires 1) a knowledge of the track-etch rate (Vsub(T))-range relationship and 2) a theoretical understanding of alpha-particle track structure in CR-39 as a function of particle energy, dip angle and degree of etching. The structure of alpha-particle etched tracks in CR-39 is described and two methods of analysis discussed. Examples are given of the resolution attainable on tracks of ...
The development of tough #alpha#-SiAlON with elongated grains in the last five years is summarized. This progress has been guided by the improved understanding of phase relations and nucleation/growth kinetics in SiAlON ceramics. Although most #alpha#-SiAlON compositions can be processed to contain some elongated grains, their microstructure, fracture toughness and R-curve behavior vary greatly. Such variability is due to the different phase stability of #alpha#-SiAlONs and the varying physical chemistry of the competing phases, including the transient/residual liquid. For this reason, microstructure control of #alpha#-SiAlON must pay close attention to the composition, starting powder and heating schedule. Seeding with single crystals of an appropriate #alpha#-SiAlON composition provides an attractive alternative that simplifies the task of microstructure control, since such seeds ...
The crystallography of #alpha#(hcp) precipitates formed on the #beta#(bcc) matrix grain boundaries has been studied with transmission electron microscopy (TEM) in a Ti-15V-3Cr-3Sn-3Al alloy. The #alpha# precipitates have a near-Burgers orientation relationship with respect to at least one of the adjacent #beta# grains. Among the possible 12 variants in this orientation relationship, the variant that [11 bar 20]_#alpha# is parallel to the _#beta# closest to the grain boundary plane tends to be preferred by the #alpha# precipitates. Additionally, further variant selections are made so as to minimize the deviation of orientation relationship with respect to the ''opposite'' #beta# grain from the Burgers one. Such rules in variant selection often result in the formation of precipitates with a single variant at a planar grain boundary. Prior small deformation of #beta# matrix changes the variant of ...
ABSTRACT: Metabolomic analysis will provide the next large set of clues to further our understanding of human health and disease. A recent study has elucidated the significant differences in the metabolomes of adipocytes, serum and an adipocyte cell line after activation of two nuclear receptors, peroxisome proliferator activated receptor ?/? (PPAR?/?) and PPAR?. These findings hold great promise for explaining fundamental differences in the mechanisms of PPAR agonists and for identifying targets for the treatment of diabetes.See related research article: http://genomebiology.com/2011/12/8/R75. PMID:21861850
Resistance and tolerance are two types of host defense mechanisms that increase fitness in response to fungi. Several genetic polymorphisms in pattern recognition receptors, most remarkably Toll-like receptors (TLRs), have been described to influence resistance and tolerance to aspergillosis in distinct clinical settings. TLRs on dendritic cells pivotally contribute in determining the balance between immunopathology and protective immunity to the fungus. Epithelial cells also contribute to this balance via selected TLRs converging on indoleamine-2,3-dioxygenase (IDO). Studies in experimental hematopoietic transplantation confirmed the dichotomy of pathways leading to resistance and tolerance to the fungus providing new insights on the relative contribution of the hematopoietic/nonhematopoi...
Serotonin is one of the neurotransmitters found in the brain and mediates brain functions. It is very well known that serotonin related brain abnormalities are exerted mainly via serotonin receptors in a similar manner to other neurotransmitters found in the brain. Recently, it has also been found that serotonin is involved in Alzheimer's disease either directly or indirectly by its actions on serotonergic neurons. To understand and treat the diseases caused by abnormalities in the serotonergic system in the brain, it is certain that its mechanism of function has to be well investigated. So far several 5-HT receptors and receptor subtypes have been well characterized. Moreover, serotonin agonists and antagonists acting on specific receptors are chemically synthesized and are now available for the prevention or treatment of serotonergic related diseases. In recent years, a great demand for developing ...
Trastuzumab increases survival amongst women with human epidermal growth factor receptor (HER)-2 receptor positive metastatic breast cancer, but maternal and fetal risks are associated with advanced disease and its treatment in pregnancy. We present a case of a primigravid with HER-2 positive metastatic breast cancer who received trastuzumab throughout pregnancy. She presented with cerebral metastases, requiring surgical decompression and resection. Reversible oligohydramnios developed during pregnancy. Fetal safety data on trastuzumab in pregnancy is limited, but case reports suggest a recurring pattern of (mostly reversible) oligohydramnios.
The possibilities for therapy in the field of severe cardiac insufficiency have been extended in recent years by the introduction of novel agents endowed with a positive inotropic action. These substances may be arranged in two large classes: sympathomimetic agents and "non sympathomimetic--non digitalis-like" inotropic agents. The stimulant action of noradrenaline, adrenaline and isoproterenol on beta-adrenergic myocardial receptors has been clearly demonstrated but the usefulness of these medicines is limited by their positive chronotropic and arrhythmogenic actions. Dopamine and dobutamine have proved to be very useful in the treatment of patients in intensive care units. However, the exclusively intravenous route of administration limits their importance to the medium or long term. Several compounds, which are active by the oral route, have been the subject of therapeutic trials for the short or medium term. The problems posed by their use result, in the first ...
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 ...
Screening of a human placenta lambdagt11 library has led to the isolation of the cDNA for the human ..beta../sub 1/-adrenergic receptor (..beta../sub 1/AR). Used as the probe was the human genomic clone termed G-21. This clone, which contains an intronless gene for a putative receptor, was previously isolated by virtue of its cross hybridization with the human ..beta../sub 2/-adrenergic receptor (..beta../sub 2/AR). The 2.4-kilobase cDNA for the human ..beta../sub 1/AR encodes a protein of 477 amino acid residues that is 69% homologous with the avian ..beta..AR but only 54% homologous with the human ..beta../sub 2/AR. This suggests that the avian gene encoding ..beta..AR and the human gene encoding ..beta../sub 1/AR evolved from a common ancestral gene. RNA blot analysis indicates a message of 2.5 kilobases in rat tissues, with a pattern of tissue distribution consistent with ..beta../sub 1/AR binding. This pattern is quite ...
The objectives of this research were to investigate the possibility of controlling the #alpha#'/#beta#' phase ratio and morphology in Sialon ceramics. These objectives have been sought by the control of the starting composition, and by post sintering heat treatment. The main emphasis has been on the production of a series of #alpha#' and (#alpha#'+#beta#') Sialon ceramics with a minimum amount of the glass phase by the pressureless sintering technique and using ytterbium (Yb) as an #alpha#' stabilising element. The Yb additions were made via the oxide or the alumino- silicate presynthesised glass; the latter was found to improve the density. The XRD analysis of the as sintered materials revealed #alpha#' to be the dominant phase with minor contributions from #beta#' sialon and/ or 12H A1N polytype. Additions of SiO_2 or #beta#-Si_3N_4 were made to various materials to assess ...
Precise measurements of alpha particle counting efficiencies have been made using isotropic, infinitely thin alpha emitting sources placed in direct contact with a thin, end-window, gas flow proportional detector. Except for alpha particle absorption in the window material, this geometry approaches 2#pi#, such that the only other variation in the response of the counter is from the random decay of the source. The data are fitted to the expected linear function of count rate versus window thickness and the resulting fitting parameters are used to calculate the counting efficiencies for a given thickness of window material. Counting efficiencies for 5.31, 6.06, and 8,78 MeV alpha particles have been determined from sources of "2"1"0Po and the progeny of "2"1"2Pb. For the particular counter used, the counting efficiencies in counts per alpha and their respective relative standard ...
Aim: There has been a great demand for developments of the radioligands to visualize the N-methyl-D-aspartate (NMDA) receptors by PET/SPECT. We have recently synthesized two C-11 labeled antagonists for the glycine-binding site on NMDA receptors. The aim of this work is to examine for their in vitro and in vivo binding characteristics, and to evaluate their potentials as PET radioligands for the NMDA receptors. Materials and methods: Two C-11 labeled 4-hydroxy-2-quinolones (1 and 2) were synthesized by conventional methylation of the corresponding phenols with ["1"1C]methyl iodide. In vitro and ex vivo quantitative autoradiographs with imaging plate, as well as animal PET, were employed in order to evaluate their in vitro and in vivo binding to the NMDA receptors. Results: The compound 1 showed the specific binding to rat brain slices with higher localization in the hippocampus and cerebral cortex than ...
This article concerns the synergetic effects between an MoO{sub 3} sample composed of crystallites exposing preferentially the (010) basal faces and {alpha}-Sb{sub 2}O{sub 4} in the oxygen-assisted dehydration of 2-butanol at 220 C. The conversion of 2-butanol and the yield to butene improved when MoO{sub 3} was reacted in the presence of {alpha}-Sb{sub 2}O{sub 4}. The origin of the synergism is discussed. When reacted in the absence of {alpha}-Sb{sub 2}O{sub 4}, MoO{sub 3} got over-reduced and fragmented to MoO{sub 2}. MoO{sub 2} is intrinsically less active than MoO{sub 3} thus explaining that the deep reduction of MoO{sub 3} corresponds to its tendency to deactivate. In the presence of {alpha}-Sb{sub 2}O{sub 4}, the formation of MoO{sub 2} is inhibited with, as a consequence, the absence of deactivation. This leads to the synergetic effects obtained with the mechanical mixture of MoO{sub 3} with ...
For several decades, ceramic matrix composite have been attracted attention in advanced structural and tribological applications. Advanced structural ceramics are presently used in diverse tribological applications such as tips for ballpoint pens, precision instrument bearings and cutting tools inserts. Design and selection of ceramics for these applications require reliable data on the effects of temperature, load and environment on the tribological behavior of these ceramics. In the present work, #alpha#-sialon matrix composites reinforced with different amounts of #beta#-sialon fibers were produced with the aim of improving their toughness to increase the industrial applications. The wear properties of #alpha#-sialon matrix composites were evaluated by carried out wear tests using a pin-on-disk tribometer under dry conditions. The #alpha#-sialon matrix composites were manufactured by slip casting and sintered by uniaxial ...
The energy spectra of energetic confined alpha particles are being measured using the pellet charge exchange method [R. K. Fisher, J. S. Leffler, A. M. Howald, and P. B. Parks, Fusion Technol. 13, 536 (1988)]. The technique uses the dense ablation cloud surrounding an injected impurity pellet to neutralize a fraction of the incident alpha particles, allowing them to escape from the plasma where their energy spectrum can be measured using a neutral particle analyzer. The signal calculations given in the above-mentioned reference disregarded the effects of the alpha particles' helical Larmor orbits, which causes the alphas to make multiple passes through the cloud. Other effects such as electron ionization by plasma and ablation cloud electrons and the effect of the charge state composition of the cloud, were also neglected. This report considers these issues, reformulates the signal level calculation, ...
The effect of one on-ramp (entry) and one off-ramp (exit) is investigated numerically in one dimensional-cellular automaton traffic flow model, with open boundary conditions, using parallel dynamics. Our aim in this paper is to study how the injecting rates $\\alpha$ and $\\alpha_{0}$ and the extracting rates $\\beta$ and $\\beta_{0}$ acts on the density and flux of cars in one dimensional road. The priority of occupation at entry site $i_{1}$ (moving at exit site $i_{2}$) is attributed to the particle which entered (absorbed) in the chain. Phase diagrams in ($\\beta_{0},\\alpha_{0}$), and ($\\beta,\\alpha_{0}$) plans are established. For $\\alpha=0.1$, they show three different topologies in the flow behaviour. The first one correspond to the presence of four regions, by varying $\\alpha_{0}$; namely low density phase (LDP), intermediate density phase (IDP), ...
The detailed electronic energy band structure of hexagonal close-packed #alpha#-zirconium, corresponding to the atomic configuration of 4d"25s"2 of its four outermost valence electrons, has been computed by the composite-wave variational version of the augmented-plane-wave(APW) method in conjunction with the X#alpha#(#alpha# = 0.70424) exchange approximation for obtaining the potentials. From these data the electronic density of states and its angular-momentum-decomposed components have been obtained by the Raubenheimer-Gilat method. These quantities are required in order to calculate the electron-phonon interaction parameter (lambda) and the superconducting transition temperature (Tsub(c)) within the framework of the theories of Gaspari and Gyorffy and McMillan. A study of the variation of Tsub(c) with the Coulomb pseudopotential (#mu#*) revealed that #mu#* = 0.1 yields the best agreement between theory and experiment for ...
A radiochemical charged particle activation procedure for production and separation of carrier free {sup 52,56}Mn, {sup 55,56,58}Co and {sup 56,57}Ni has been developed. The radioisotopes produced on bombardment of an iron foil target with a 40 MeV {alpha}-particle beam through the nuclear reactions, Fe({alpha}, {alpha}pxn){sup 52,56}Mn, Fe({alpha}, pxn){sup 55,56,58}Co and Fe({alpha}, nx){sup 56,57}Ni, have been separated by LLX. The target element and the activation products have been sequentially separated from an HCl medium using diethylether and the liquid anion exchanger, TIOA, as extractants. Extent of separation and purity of the carrier free radiotracers at different stages of their LLX separation have been verified by taking recourse to {gamma}-ray spectrometry. (Author).
For optimizing the microstructure of the (#alpha# + #beta#)-titanium alloy TiAl5Fe2.5 the content of the two alloying elements aluminium and iron in the #alpha#- and #beta#-phase was determined by microprobe analysis. The alloys with the composition of the #alpha#- and of the #beta#-phase at 850 degC TiAl6Fe0.5 (#alpha#-phase) and TiAl3.5Fe6.5 (#beta#-phase) were prepared by arc melting and rolling at 850 degC. The mechanical properties of the '#alpha#'- and of the '#beta#'-phase-alloy are compared with the properties of the (#alpha# + #beta#)-alloy TiAl5Fe2.5 in the as rolled and swaged condition and after an additional aging at 550 degC. By this optimizing process it was possible to achieve a tensile strength of Rsub(m) = 1012 N/mm"2, an yield strength of Rsub(p0.2) 954 N/mm"2 and an elongation at fracture A = 14.5% in the TiAl5Fe2.5-alloy, although the degree ...
Powders with nominal compositions (in atomic percent) Ti-48Al and Ti-48Al-2Nb-2Cr were prepared by the plasma rotating electrode process (PREP) and gas atomization (GA) techniques. As-solidified and heat-treated (1000degC per 3 h) powder samples were examined by metallography, scanning electron microscopy, X-ray diffraction and transmission electron microscopy. The microstructures of the powders were characterized as a function of atomization technique, alloy content, powder particle size (solidification rate) and thermal history. All of the as-solidified powders were comprised of disordered [alpha], and ordered [alpha][sub 2]-Ti[sub 3]Al and [gamma]-TiAl. For both alloys, a larger volume fraction of [alpha] and [alpha][sub 2] was observed in the PREP powders relative to GA powders of comparable size. Additionally, for both alloys and both atomization techniques, the volume fraction of ...
Theoretical interpretation of fast-charged-particle spectra, observed in the #alpha#-particle-induced reactions on the s-d shell nuclei (A = 24-28), in terms of the Intranuclear Cascade Model and the GDH exciton model (ALICE) is presented. The de-excitation of the excited residual nuclei is accounted for by the evaporation process. The theoretically predicted fast-proton and #alpha#' spectral shapes compare reasonably well with the corresponding measured spectra. However, the magnitude depends critically (as expected) on the reaction cross section employed by the model. As a first step to improve the model predictability of the reaction products, a closer look at the calculation of the #alpha#-particle reaction cross sections was undertaken. A microscopic approach using the optical theorem of Glauber's theory was employed to estimate the #alpha#-induced reaction cross sections for the light target ...
The unit cost of energy production of wind generators is examined by means of a model of the turbine power curve and the Weibull model of wind probability function, by applying the usual economic equations. The analysis is carried out in terms of dimensionless variables whose range of variability is defined by examining the data of 80 modern commercial wind turbines; likewise, the economic parameters are based on the present state of costs. The unit cost decreases asymptotically when alpha (ratio between mean wind speed and cut-in speed) - increases and shows a lower limit of 2 to 5 Ecent/kWh. This cost depends both on the value of the machine parameter {phi} (ratio between nominal and cut-in speed) and on the basic prices. The effect of the Weibull shape parameter kappa is different according to the values of {alpha} and {phi}: with low {alpha} and high {phi} the unit cost increases along with {kappa} (that is with the ...
Treatment of cultures of 3T3-L1 cells with methylisobutyl-xanthine and dexamethasone has been shown to result in accumulation of lipid and conversion to the morphology of adipocytes in more than 90% of the cells. The status of the stimulatory (Gs), inhibitory (Gi) and Go-proteins during the course of 3T3-L1 differentiation was examined. The amount of alpha subunit of Gs (#alpha#Gs), assayed by radiolabeling in the presence of cholera toxin and ["3"2P]NAD"+, increased upon differentiation as previously described by others. The amounts of #alpha#Gi and #alpha#Go assayed by radiolabeling in the presence of pertussis toxin and ["3"2P]NAD"+ increased 3-fold upon differentiation. Immunoblots of cell membranes subjected to gel electrophoresis in sodium dodecyl sulfate were probed with two rabbit antisera raised against bovine brain #alpha#Go and with one raised against the#beta#-subunit of ...
We compute the complete two-loop O(alpha) Wilson coefficients relevant for radiative decays of the B meson in the SM. This is a necessary step in the calculation of the O(alphaalpha_s^n ln^n m_b/M_W) corrections and improves on our previous analysis of electroweak effects in B -> X_s gamma. We describe in detail several interesting technical aspects of the calculation and include all dominant QED matrix elements. In our final result, we neglect only terms originated from the unknown O(alphaalpha_s) evolution of the Wilson coefficients and some suppressed two-loop matrix elements. Due to the compensation among different effects, we find that non-trivial electroweak corrections decrease the branching ratio by about 3.8% for a light Higgs boson, in agreement with our previous analysis. As in [1], the corresponding SM prediction for the branching ratio with E_gamma > 1.6 GeV is ...
The broad bands in the room-temperature excitation spectra of Sm"3"+-, Dy"3"+- and Tm"3"+-activated Ca-#alpha#-SiAlON phosphors are interpreted as the N"3"--to-rare earth charge transfer transition (CTT). From the energies of the charge transfer transitions and from the optical data presented for the Eu"2"+ ion, the location of the divalent rare earth ion energy levels relative to the valence and the conduction band of Ca-#alpha#-SiAlON is derived. The salient features of the energy-level diagram are shown to be practical in explaining the temperature-dependent variations of the Eu"2"+ and Yb"2"+ luminescence efficiency in Ca-#alpha#-SiAlON. A comparative study pertaining to the nature of the Yb"2"+ and Eu"2"+ ion luminescence in Ca-#alpha#-SiAlON and in SrSi_2O_2N_2 is presented. A tentative energy-level diagram of the trivalent rare earth ions in Ca-#alpha#-SiAlON is also ...
The effect of the nitrogen uptake in {alpha}-iron upon spark erosion in gaseous and liquid ammonia, plasma nitriding, and plasma immersion ion implantation is studied. The resulting phases and hyperfine parameters, measured by the Moessbauer spectroscopy, are discussed from the point of view of initial conditions of their preparation and subsequent heat and/or mechanical treatment. Spark erosion in the ammonia gas produces fine particles with the dominating ferromagnetic {alpha}-Fe phase (50%). The 20% of specimen volume form {alpha}'-Fe and {alpha}''-Fe{sub 16}N{sub 2} phases. The last 30% occupy the {gamma}'-Fe{sub 4}N, ferro- and paramagnetic {epsilon} phases, and {gamma}-Fe(N). Nitriding in the liquid ammonia allows to incorporate the higher content of nitrogen into {alpha}-iron particles which results in the formation of paramagnetic ...
The effect of the nitrogen uptake in #alpha#-iron upon spark erosion in gaseous and liquid ammonia, plasma nitriding, and plasma immersion ion implantation is studied. The resulting phases and hyperfine parameters, measured by the Moessbauer spectroscopy, are discussed from the point of view of initial conditions of their preparation and subsequent heat and/or mechanical treatment. Spark erosion in the ammonia gas produces fine particles with the dominating ferromagnetic #alpha#-Fe phase (50%). The 20% of specimen volume form #alpha#'-Fe and #alpha#''-Fe_1_6N_2 phases. The last 30% occupy the #gamma#'-Fe_4N, ferro- and paramagnetic #epsilon# phases, and #gamma#-Fe(N). Nitriding in the liquid ammonia allows to incorporate the higher content of nitrogen into #alpha#-iron particles which results in the formation of paramagnetic #epsilon#(#zeta#)-Fe_2N phase. This phase also dominates ...
New and elaborate techniques for alpha-particle autoradiography of thick specimens based on the plastic nuclear track detector CR-39 have been developed. These permit a full analysis of both trace element and microdistribution of alpha-active nuclides present. The important features of the techniques are: 1) reliable low level configuration down to 10/sup -15/ Ci g/sup -1/, 2) high resolution alpha-particle spectroscopy in CR-39, 3) determination of the absolute abundance of alpha active nuclides present in the specimen, 4) determination of the distribution of emission with height up to 30 microns above the surface of the autoradiograph, 5) the local determination of the radon diffusion coefficient in the specimen which is needed to calculate the activity levels of /sup 222/Rn and daughter nuclei, 6) the analysis of small and large clusters of alpha-particle activity recorded on the ...
The soluble pool of alpha hemoglobin chains present in blood or bone marrow cells was measured with a new affinity method using a specific probe, beta A hemoglobin chain labeled with ["3H]N-ethylmaleimide. This pool of soluble alpha chains was 0.067 #+-# 0.017% of hemoglobin in blood of normal adult, 0.11 #+-# 0.03% in heterozygous beta thalassemia and ranged from 0.26 to 1.30% in homozygous beta thalassemia intermedia. This elevated pool of soluble alpha chains observed in human beta thalassemia intermedia decreased 33-fold from a value of 10% of total hemoglobin in bone marrow cells to 0.3% in the most dense red blood cells. The amount of insoluble alpha chains was measured by using the polyacrylamide gel electrophoresis in urea and Triton X-100. In beta thalassemia intermedia the amount of insoluble alpha chains was correlated with the decreased spectrin content of red cell ...
The Drell-Yan mechanism for the production of lepton pairs is one of the most basic processes for physics studies at hadron colliders. It is therefore important to have accurate theoretical predictions. In this work we compute the two-loop virtual mixed QCD x QED corrections to Drell-Yan production. We evaluate the Feynman diagrams by decomposing the amplitudes into a set of known master integrals and their coefficients, which allows us to derive an analytical result. We also perform a detailed study of the ultraviolet and infrared structure of the two-loop amplitude and the corresponding poles in epsilon.
We present numerical calculations for cesium and mercury to estimate the sensitivity of the scattering length to the variation of the fine structure constant alpha. The method used follows ideas Chin and Flambaum [Phys. Rev. Lett. 96, 230801 (2006)], where the sensitivity to the variation of the electron to proton mass ratio, beta, was considered. We demonstrate that for heavy systems, the sensitivity to variation of alpha is of the same order of magnitude as to variation of beta. Near narrow Feshbach resonances the enhancement of the sensitivity may exceed nine orders of magnitude.
The K_#beta#/K_#alpha# X-ray intensity ratios are measured for Mn and Fe and for six other elements with Z lying in the range 49<=Z<=82 following electron capture decay and photon excitation using "2"4"1Am and "5"7Co sources. High-resolution Si(Li) and HpGe detector systems were used in the experiments. The dependence of K_#beta#/K_#alpha# values on the mode of excitation in the case of Mn and Fe is attribuited to the chemical effects, while no such dependence is found for the high-Z elements.
By employing the higher dimensional version of the Wu-Yang Ansatz we obtain magnetically charged new black hole solutions in the Einstein-Yang-Mills-Lovelock (EYML) theory with second ($\\alpha2$) and third ($\\alpha3$)order parameters. These parameters, where $\\alpha2$ is also known as the Gauss-Bonnet parameter, modify the horizons (and the resulting thermodynamical properties) of the black holes. It is shown also that asymptotically, these parameters contribute to an effective cosmological constant -without cosmological constant- so that the solution behaves de-Sitter (Anti de-Sitter) like.
Hitherto in this laboratory, ionization coefficients alpha and attachment coefficients #eta# have been determined from Townsend's discharge experiments by a curve-fitting method. However, the method proved to be laborious, Formulae have been derived in this paper to give value of alpha and #eta# as a function of Isubo, Isub1 and Isub2 where Isubo is the photoelectric current at a gap setting d and Isub2 the current at another gap setting 2 d. The values of alpha and #eta# obtained give currents in agreement to within 3% in the best cases with the observed currents.
The methods of optical and transmission electron microscopy were used to study the influence of different programmes of hot deformation on the structure formation of (#alpha#+#beta#) titanium alloy VT9. The #beta# alloy VT-15 was studied at the same time in order to simulate the dislocation structure generated in the process of hot deformation. During the hot deformation of two-phase titanium alloys in both #beta# and (#alpha#+#beta#) ranges there is found to be an optimum range of deformation in which a homogeneous, polygonized structure is formed.
The effect of variations of the fundamental constants on the thermonuclear rate of the triple alpha reaction, "4He(#alpha##alpha#, #gamma#)"1"2C, that bridges the gap between "4He and "1"2C is investigated. We have followed the evolution of 15 and 60 M#centre dot# zero metallicity stellar models, up to the end of core helium burning. They are assumed to be representative of the first (Population III) stars. The calculated oxygen carbon abundances resulting from helium burning can then be used to constrain the variation of the fundamental constants.
This paper reviews and elaborates on the issue of the dilaton transformation under the usual {tau} {yields} {alpha}{prime}/{tau} target space duality and its non-static generalization (or {sigma}-model duality). It is found that the transformation law {tau} {yields} {alpha}{prime}/{tau}, {phi} {yields} {phi} In ({tau}/{alpha}{prime}) which guarantees duality at the one-loop {sigma}-model level should be modified at two (and higher) loop order. The non-static duality is illustrated on the example of cosmological solutions in D {ge} 2 with time-dependent radii of space torus.
Nano-indentation has been used to assess the hardness of equiaxed grains of #alpha#-Ti as a function of orientation. Surface normals of these grains in metallographic sections were assessed using orientation imaging microscopy. Thin membranes of material from below a series of nano-indentations were excised by use of a dual-beam focused ion beam instrument. In this way, the dislocation substructures beneath individual indentations were characterized using transmission electron microscopy, permitting an identification of both statistically stored and geometrically necessary dislocations.
The purpose of the present research is to find a suitable technique to measure trace amounts of uranium and thorium and to determine the surface #alpha#-flux in silicon compound (SiO) used for fabrication of integrated circuit packaging materials. Among several commonly-used detecting techniques, it was found that neutron activation analysis (NAA) was most promising. The results from NAA show a large difference in uranium and thorium concentrations when cadmium and boron carbide shields are used, whereas #alpha#-flux measurements show a low #alpha#-activity, which corresponds to the trace amounts of uranium and thorium expected to be present in these materials. (author) 13 refs.; 6 figs.
Bremsstrahlung emitted in the {alpha}+p reaction at 50 MeV/nucleon was studied using a 200 MeV {alpha}-particle beam and a liquid hydrogen target. Double-differential photon cross sections were measured over a wide range of angles and energies. Coherent bremsstrahlung was found to be strong for all photon energies. The cross section is enhanced at the highest photon energies and is characteristic of direct capture to the unbound {sup 5}Li ground and first excited state. With direct capture as a limiting case of coherent bremsstrahlung a consistent reaction picture can be obtained.
The charge distribution in the alpha particle induced fission of "2"0"9Bi has been studied at alpha particle energy of 55.7 MeV and 58.6 MeV. The fractional cumulative yields of "9"7Zr, "9"9Mo, "1"0"1Mo and "1"1"2Pd have been determined using gamma ray spectrometry. The charge distribution have been found to be broad. (author). 4 refs., 1 ta b.
This paper describes and analyzes a dithering technique for accurately specifying small values of opacity ({alpha}) that would normally not be possible because of the limited number of bits available in the alpha channel of graphics hardware. This dithering technique addresses problems related to compositing numerous low-opacity semitransparent polygons to create volumetric effects with graphics hardware. The paper also describes the causes and a possible solution to artifacts that arise from parallel or distributed volume rendering using bricking on multiple GPU's.
Titanium base 'alpha'-alloys (Pt-7M, RK-20 and Ti-5Al-2Zr-1.5V) are considered for their behaviour under neutron irradiation. The role of alloying elements in radiation hardening is discussed depending of neutron fluence and irradiation temperature. For PK-20 alloy three stages of change in mechanical properties are revealed which are following: incubation period and weak hardening, intense radiation hardening, radiation hardening attenuation. Irradiation temperature rise results in an increase of incubation period and threshold neutron fluence. A special attention is paid to hydrogen absorption in #alpha#-titanium alloys under irradiation. It is concluded that titanium base 'alpha'-alloys are serviceable as structural materials in nuclear plants with allowance made for peculiar features of their radiation behaviour. 4 refs.; 7 figs.; 1 tab.
We discuss the foundations of factor or regression models in the light of the self-consistency condition that the market portfolio (and more generally the risk factors) is (are) constituted of the assets whose returns it is (they are) supposed to explain. As already reported in several articles, self-consistency implies correlations between the return disturbances. As a consequence, the alpha's and beta's of the factor model are unobservable. Self-consistency leads to renormalized beta's with zero effective alpha's, which are observable with standard OLS regressions. Analytical derivations and numerical simulations show that, for arbitrary choices of the proxy which are different from the true market portfolio, a modified linear regression holds with a non-zero value $\\alpha_i$ at the origin between an asset $i$'s return and the proxy's return. Self-consistency also introduces ``orthogonality'' and ``normality'' conditions ...
In this paper, we investigate the epidemic spreading for SIR model in weighted scale-free networks with nonlinear infectivity, where the transmission rate in our analytical model is weighted. Concretely, we introduce the infectivity exponent $\\alpha$ and the weight exponent $\\beta$ into the analytical SIR model, then examine the combination effects of $\\alpha$ and $\\beta$ on the epidemic threshold and phase transition. We show that one can adjust the values of $\\alpha$ and $\\beta$ to rebuild the epidemic threshold to a finite value, and it is observed that the steady epidemic prevalence $R$ grows in an exponential form in the early stage, then follows hierarchical dynamics. Furthermore, we find $\\alpha$ is more sensitive than $\\beta$ in the transformation of the epidemic threshold and epidemic prevalence, which might deliver some useful information or new insights in the epidemic spreading and ...