bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conducting fieldwork with Tarieng communities in southern Laos: Negotiating discursive spaces between neoliberal dogmas and Lao socialist ideology
Authors: Daviau Steeve 
Published: July 2010

AbstractBased on research with ethnic minorities in Laos aimed at understanding how they cope with and negotiate political and economic ‘double domination’, this article examines the experiences of prolonged fieldwork in a remote Tarieng area in the Annam Range, southern Laos. After briefly reviewing Lao ethnographical policy and practice regarding ethnic minorities, I introduce the Tarieng people. I detail how I initially gained access to these local communities via long‐term engagement with a range of development project initiatives. Then, after eight years of conducting such fieldwork in a Tarieng area ‘below the radar of the state’, I managed to obtain official authorisations to continue research as a graduate student. In this new position, I accessed the field via different negotiations with central, provincial and local official bureaucracies. After detailing this process, back in the field I reveal my strategies to create a discursive space that has allowed me to access dissident Tarieng voices and agency. Finally, I highlight four central elements that have continued to shape my field research: language proficiency, working with research assistants, awareness of political relations and cultural sensitivity, and ethical concerns. These have emerged while the possibilities and constraints of political engagement with the Tarieng people are explored.
THE EFFECT OF HYPOXIA ON THE PENTOSE PHOSPHATE PATHWAY IN BRAIN
Authors: Hakim A. M. , Moss G. , Gollomp S. M. 
Published: July 2010

Abstract—The role of the pentose phosphate pathway in brain glucose metabolism was studied in hypoxic rats. The method of directly labelling the 6‐phosphogluconate pool was used in both in vivo and in vitro experiments. Results indicate that there is significantly more glucose metabolized via this pathway in brains of hypoxic rats than in the controls.
THE REGULATION OF PYRUVATE DEHYDROGENASE IN BRAIN IN VIVO
Authors: Jope R. , Blass J. P. 
Published: July 2010

Abstract—The activity of pyruvate dehydrogenase in the brains of mice frozen in liquid nitrogen was 14·0 nmol/min per mg protein. It rose to 23·8 nmol/min per mg protein after incubation of the brain homogenate with 10mm‐MgCl2 to activate (dephosphorylate) the enzyme, indicating that approx 60% of the enzyme was originally in the active form. Treatment with amobarbital or pentobarbital halved the proportion of pyruvate dehydrogenase in the active form. The proportion of pyruvate dehydrogenase in the active form increased during ischemia, activation being complete within one min. Anesthesia with amobarbital slowed the activation during ischemia but did not alter the total amount of pyruvate dehydrogenase activity. The concentration of ATP, the ATP/ADP ratio and the adenylate energy charge increased as the proportion of pyruvate dehydrogenase in the active form decreased during barbiturate anesthesia, and they decreased as the proportion of pyruvate dehydrogenase in the active form increased during ischemia. After treatment with insulin, the proportion of pyruvate dehydrogenase in the active form increased by 30%. but the energy charge did not change. Treatment of mice with ether, morphine, ethanol, or diazepam did not change the proportion of pyruvate dehydrogenase in the active form although these treatments have been reported to alter pyruvate oxidation in brain in vivo. Treatments which altered pyruvate oxidation in the brain did not consistently alter the proportion of pyruvate dehydrogenase in the active form, unless they also altered energy charge.
MICROHETEROGENEITY AND PHOSPHOAMINO ACIDS IN THE CARBOXY‐TERMINAL HALF OF MYELIN BASIC PROTEIN
Authors: Martenson R. E. , Kramer A. J. , Deibler Gladys E. 
Published: July 2010

Abstract—Three chromatographically distinct peptic peptides (F80‐1, F80‐2 and F80‐3) derived from the C‐terminal half of the bovine and guinea‐pig myelin basic proteins were characterized. The three peptides of each animal species had the same N‐terminal residue (phenylalanine) and essentially the same amino acid composition, but they differed in electrophoretic mobility at alkaline pH. The least basic peptide (F80‐3) differed from the others in showing a deficit of C‐terminal arginine residues and in containing phosphorus, 0·37 and 0·46 g‐atom/mol of bovine and guinea‐pig peptides, respectively. Other peptic peptides. derived from the N‐terminal half of the basic protein, were essentially phosphorus‐frcc. Analyses of partial acid hydrolyzates of peptide F80‐3 by high voltage electrophoresis showed the presence of both phosphoserine and phosphothreonine. After incubation with E. coli alkaline phosphatase (EC 3.1.3.1). 34 and 40% of the bovine and guinea‐pig F80‐3 peptides. respectively, were converted to peptide F80‐1. This reaction involved the loss of 2 net negative charges, and its extent corresponded to loss of essentially all of the phosphate originally present in the peptide. This result indicated that the phosphorylated species of peptide F80‐3 contained one phosphate group per molecule.
TRANSMITTER METABOLIZING ENZYMES AND FREE AMINO ACID LEVELS IN SENSORY AND MOTOR NERVES AND GANGLIA OF THE SHORE CRAB (CARCINUS MAENAS)
Authors: Emson P. C. , Bush B. M. H. , Joseph M. H. 
Published: July 2010

Abstract—The distribution of ChAT (choline acetyltransferase), GAD (glutamate decarboxylase) and acetylcholinesterase in some sensory and motor nerves of the shore crab, Carcinus maenas, has been investigated using micro‐assay techniques. ChAT was concentrated in the afferent nerve fibres of the thoracic‐coxal muscle receptor as well as in the coxo‐basal chordotonal receptor nerve and other leg sensory fibres. GAD was found in leg motor nerves including the promotor and remotor muscle nerves, being undetectable in the sensory nerves. Acetylcholinesterase was found in similar levels in both sensory and motor nerves assayed.Amino acid analysis using a micro‐dansylation technique showed that sensory nerves had low GABA levels, whereas the leg nerve including motor fibres had substantially higher GABA concentrations. GAD and GABA were also found in low amounts in the leg promoter mucle, which is consistent with GABA being a neuromuscular transmitter.
DETERMINATION OF MONOAMINE OXIDASE IN RAT BRAIN BY ELECTRON SPIN RESONANCE TECHNIQUES
Authors: Huang Rosa H. , Eiduson S. , Shih J. C. 
Published: July 2010

Abstract—The recent development of spin‐labeling techniques has permitted its application to the measurement of the concentration of rat brain mitochondrial monoamine oxidase (MAO) and detection of possible multiple forms of this enzyme. Spin‐labeled p‐hydroxyamphetamine (SHA) was used as a probe of the active site of the enzyme. The binding of SHA to MAO was monitored by measuring the intensity of the × band ESR spectra obtained with a Varian V‐4502 ESR spectrometer. The measured volume of each sample was about 0·02 ml and time required for each measurement was 5 min. In the presence of MAO, a linear relationship was observed between spectral intensity and the concentration of the spin‐label in a range of 4 × 10−6m to 10−3m. A plot of the amount of enzyme‐inhibitor complex formed against the concentration of SHA suggested the existence of at least three different affinities of SHA to the possible multiple forms of MAO. Measurements made using a constant concentration of the spin‐label (3·21 × 10−5m) resulted in a calibration curve with two plateaus when the concentration of the enzyme‐inhibitor complex was plotted against the apparent concentration of MAO. These data also suggested that spin‐labeled hydroxyamphetamine had distinctly different affinities toward the multiple forms of MAO that were present in the partially purified preparation employed. Measurements made with constant concentrations of SHA and MAO but with varying temperatures (4‐56°C) resulted in a curve with two plateaus which also suggested the existence of at least three different binding affinities of the enzyme preparation for the inhibitor. This ESR technique is simple, rapid, accurate and fairly sensitive. It was also applied to the measurement of MAO in human platelets.
Parvalbumin in Cat Brain: Isolation, Characterization, and Localization
Authors: Stichel Christine C. , Kägi Urs , Heizmann Claus W. 
Published: July 2010

AbstractBecause of the increasing evidence that Ca2+‐binding proteins have important regulating functions in nerve cells and because of the indications that there are species differences in the structures of these proteins, parvalbumin was purified from cat brain and muscle. Brain and muscle parvalbumins were found to be indistinguishable from each other in their biochemical and im‐munological properties. However, cat parvalbumin differs from all other mammalian parvalbumins by its apparently lower Mr on sodium dodecyl sulfate‐polyacryl‐amide gel electrophoresis of 10–11K (compared to rat parvalbumin, 12K), and a lower pI of 4.6 (rat parvalbumin, 4.9), in the tryptic peptide maps, and in the immu‐nological properties, indicating a distinct primary structure. With the purified parvalbumin as antigen, polyclonal antibodies were raised in rabbits and these were subsequently used for immunohistochemical localizations of parvalbumin in the cat brain. In the visual cortices of adult cats immunoreactive neurons were present throughout layers II and IV. In cerebellar cortex. Pur‐kinje, basket, and stellate cells were immunoreactive. Comparison with staining patterns obtained with anti‐serum against rat parvalbumin revealed some cross‐reactivity but confirmed the existence of species differences in the antigenic structure of rat and cat parvalbumin.
Identification and Initial Characterization of Adipokinetic Hormone‐Like Immunoreactive Peptides of Rat Origin
Authors: Schueler Paula A. , Elde Robert P. , Herman William S. , Mahoney Walter C. 
Published: July 2010

AbstractAn antiserum was raised to adipokinetic hormone (AKH), a 10‐amino‐acid‐residue peptide found in the arthropod Locusta migratoria. The antiserum demonstrated not only immunocytochemical reaction with some other arthropod species, but also stained many areas of the rat CNS, certain islet cells of the pancreas, and some anterior pituitary cells. The pattern of staining was unlike that for any known rat neuropeptide or hormone. With the antiserum used as the detection system, HPLC and high‐voltage electrophoresis yielded two peptides that were purified to homogeneity from rat hypothalamic median eminence. These peptides have unique amino acid compositions, indicating they may be heretofore unknown rat neuropeptides.
Exogenous Glutamate Is Metabolized to Glutamine and Exported by Rat Primary Astrocyte Cultures
Authors: Waniewski Robert A. , Martin David L. 
Published: July 2010

AbstractRat cortical astrocytes in primary culture were examined for their capacity to transport and metabolize exogenous l‐[U‐l4C]glutamate. After incubation for time periods up to 120 min, cells and incubation media were analyzed for labelled and endogenous glutamate and its metabolic products by HPLC coupled with fluorescence detection and liquid scintillation counting. Glutamine was the major labelled metabolite after 120 min, accounted for 38% of the original glutamate label, and was found primarily in the incubation medium. A further 13.5% of the label was recovered in deaminated metabolites of glutamate, 1.2% was associated with aspartate, 23% remained in glutamate, and 10.2% was found in an acid‐precipitated cell fraction. More than 84% of the label was recovered in these fractions, suggesting that the maximum possible formation and loss of I4CO2 was 16%. The rate of total glutamine synthesis was 1.1 nmol ± mg protein‐1 x min‐1 when 9 μM exogenous glutamate was present. The total amount of glutamine synthesized greatly exceeded the consumption of glutamate, indicating that a substantial proportion of glutamine was synthesized from other carbon sources. Almost all of the newly formed glutamine was exported into the medium. These results indicate that astrocytes in primary culture, by accumulating glutamate, producing glutamine, and exporting it, are capable of carrying out the glial component of the glutamine cycle.
Phosphorylation of Synaptic Membrane Glycoproteins: The Effects of Ca2+ and Calmodulin
Authors: Kearney Krystyna A. , Gurd James W. 
Published: July 2010

Abstract:Synaptic membranes were incubated with [γ‐32P]ATP, and glycoproteins were isolated by affinity chromatography on concanavalin A agarose. Glycoproteins accounted for 1.5–2.5% of the total 32P incorporated into synaptic membrane proteins. Ca2+ and calmodulin enhanced the phosphorylation of synaptic membrane glycoproteins approximately threefold. In the presence of Ca2+ and calmodulin, the rate of glycoprotein dephosphorylation was also increased three‐ to fourfold. Gel electrophoretic analysis identified several synaptic membrane glycoproteins that incorporated 32P, with the most highly labeled glycoprotein under basal phosphorylating conditions having an apparent Mr of 205,000 (gpiii). Ca2+ and calmodulin produced a marked increase in the phosphorylation of a glycoprotein with an apparent Mr of 180,000 (gpiv) and lesser increases in the labeling of three other glycoproteins. Membranes that had been labeled with [γ‐32P]ATP were extracted with Triton X‐100 under conditions that yield a detergent‐insoluble residue enriched in postsynaptic structures. The Triton X‐100 insoluble residue accounted for 20–25% of the 32P associated with synaptic membrane glycoproteins. Gpiv and other glycoproteins, the phosphorylation of which was stimulated by calmodulin, were located exclusively in the Triton X‐100 insoluble residue, whereas gpiii and other calmodulin‐insensitive glycoproteins partitioned predominantly into the Triton X‐100‐soluble fraction. Phosphopeptide maps and phosphoamino acid analysis of gpiv isolated from synaptic membranes and a postsynaptic glycoprotein of apparent Mr of 180,000 (gp180) isolated from synaptic junctions indicated that the former protein was identical to the previously identified postsynapticspecific gp180. In addition to phosphoserine and phosphothreonine, gpiv also contained phosphotyrosine, identifying it as a substrate for tyrosine‐protein kinase as well as for Ca2+/calmodulin‐dependent protein kinase.
Adrenal Medullary Tropomyosins: Purification and Biochemical Characterization
Authors: Côté A. , Doucet J.‐P. , Trifaró J.‐M. 
Published: July 2010

Abstract:Tropomyosins have been isolated from bovine adrenal medulla. Purified from a heat‐stable extract, the adrenal medulfary tropomyosins show the same chromatographic patterns as platelet tropomyosin components purified under very similar conditions on ion‐exchange (DEAE‐Sephacel) and hydroxylapatite columns. When analyzed by polyacrylamide gel electrophoresis, the purified fraction, reduced and denatured, yielded three polypeptides with apparent molecular weights of 38,000, 35,500, and 32,000. The molar ratio of the two major polypeptides (38 kd and 32 kd) was 2:1. The predominant form of 38 kd is different from other nonmuscle tropomyosins previously isolated and with which an apparent molecular weight of 30,000 is normally associated. The three adrenal medullary tropomyosins have similar isoelectric points of about 4.7. When adrenal tropomyosins were subjected to sodium dodecyl sulfate‐polyacrylamide gel electrophoresis in the presence of 8 M urea, each form showed a shift to a higher molecular weight, which is a characteristic of muscle tropomyosin. The 38,000 adrenal medullary tropomyosin exhibits a stronger affinity for F‐actin than the other forms. Peptide profiles obtained after limited proteolytic digestion show some similarity between the two predominant tropomyosins of the bovine adrenal medulla and also between these and the α and β forms of bovine skeletal muscle tropomyosin.
Transglutaminase and the Neuronal Cytoskeleton in Alzheimer's Disease
Authors: Miller Christopher C. J. , Anderton Brian H. 
Published: July 2010

Abstract:Transglutaminase [EC 2.3.2.13, (R)‐glutaminyl‐peptide:amine γ‐glutamyltransferase], an enzyme that catalyzes the introduction of glutamine‐lysine cross‐links into proteins, was purified. Neurofilament and microtubule proteins were substrates for this enzyme but the insoluble neurofibrillary tangles (NFT) isolated from Alzheimer's disease brain were not substrates. In vitro cross‐linking of neurofilaments and microtubules by the enzyme did not produce paired helical filaments (PHF), which are the major ultrastructural component of NFT. These results make it unlikely that PHF are formed by the straightforward cross‐linking of neurofilaments or microtubules.
The localisation of the extraneuronal monoamine transporter (EMT) in rat brain
Authors: Haag Christine , Berkels Reinhard , Gründemann Dirk , Lazar Andreas , Taubert Dirk , Schömig Edgar 
Published: July 2010

AbstractThe extraneuronal monoamine transporter plays an important role in the inactivation of monoamine transmitters. A basal extraneuronal tissue expression of this transporter has been reported, but it is also expressed in CNS glia. As little is known about the expression pattern and the function of the extraneuronal monoamine transporter in the brain, we performed a detailed investigation. Firstly, a northern blot analysis of different rat organs revealed that the transporter is strongly expressed in placenta, lung and heart and less prominently in the whole brain, brain stem, intestine, testis, epididymis, stomach, kidney and skeletal muscle. It was not expressed in cerebellum, liver and embryo. Using an in situ hybridization to the rat brain, we detected a marked and highly confined expression of the extraneuronal monoamine transporter in the area postrema, but in no other brain areas. These findings were confirmed by polyclonal antibodies against rat extraneuronal monoamine transporter showing an intensive signal in the area postrema, although a few cells in the cerebellum and the brain stem also showed a signal. Additionally, a partly overlapping expression pattern of the monoamine oxidase‐B was detected. Summarizing, we firstly describe a marked and highly confined expression of the extraneuronal monoamine transporter in the rat area postrema by in situ hybridisation which may play a role in physiological functions of this circumventricular organ such as emesis, food intake and the regulation of cardiovascular functions.
D1‐like dopamine receptors regulate GABAA receptor function to modulate hippocampal neural progenitor cell proliferation
Authors: Goffin Darren , Aarum Johan , Schroeder Jörn E. , Jovanovic Jasmina N. , Chuang Tsu Tshen 
Published: July 2010

AbstractThe proliferation and differentiation of neural progenitor (NP) cells can be regulated by neurotransmitters including GABA and dopamine. The present study aimed to examine how these two neurotransmitter systems interact to affect post‐natal hippocampal NP cell proliferation in vitro. Mouse hippocampal NP cells express functional GABAA receptors, which upon activation led to an increase in intracellular calcium levels via the opening of L‐type calcium channels. Activation of these GABAA receptors also caused a significant decrease in proliferation; an effect that required the entry of calcium through L‐type calcium channels. Furthermore, while activation of D1‐like dopamine receptors had no effect on proliferation, it abrogated the suppressive effects of GABAA receptor activation on proliferation. The effects of D1‐like dopamine receptors are associated with a decrease in the ability of GABAA receptors to increase intracellular calcium levels, and a reduction in the surface expression of GABAA receptors. In this way, D1‐like dopamine receptor activation can increase the proliferation of NP cells by preventing GABAA receptor‐mediated inhibition of proliferation. These results suggest that, in conditions where NP cell proliferation is under the tonic suppression of GABA, agonists which act through D1‐like dopamine receptors may increase the proliferation of neural progenitors.
The Reck tumor suppressor protein alleviates tissue damage and promotes functional recovery after transient cerebral ischemia in mice
Authors: Wang Huan , Imamura Yukio , Ishibashi Ryota , Chandana Ediriweera P. S. , Yamamoto Mako , Noda Makoto 
Published: July 2010

J. Neurochem. (2010) 115, 385–398.AbstractThe extracellular matrix (ECM) is important for both structural integrity and functions of the brain. Matrix metalloproteinases (MMPs) play major roles in ECM‐remodeling under both physiological and pathological conditions. Reversion‐inducing cysteine‐rich protein with Kazal motifs (Reck) is a membrane‐anchored MMP‐regulator implicated in coordinated regulation of pericellular proteolysis. Although patho‐physiological importance of MMPs and another group of MMP‐regulators, tissue inhibitor of metalloproteinases, in brain ischemia has been demonstrated, little is known about the role of Reck in this process. In this study, we found that Reck is up‐regulated in hippocampus and penumbra of subventricular zone after transient cerebral ischemia in mice. Most of the Reck‐positive cells found at day 2 after ischemia are positive for Nestin as well as Ki67 and localized to the CA2 region of the hippocampus. At day 7 after ischemia, the Reck‐positive cells increased in number, extended processes, expressed the reactive astrocyte marker GFAP and the neuronal marker NF200, and were widely distributed in the hippocampus. In the mutant mice carrying single functional Reck allele (Reck+/−), tissue damage and cell death after cerebral ischemia were augmented, the recovery of long‐term potentiation in the hippocampus was compromised, NR2C subunit of NMDA receptor was up‐regulated, gelatinolytic activity of MMPs were up‐regulated and laminin‐immunoreactivity was reduced. Our data implicate Reck in protection of ECM/tissue integrity and promotion of functional recovery in the brain after transient cerebral ischemia.
A Contribution to the Chemistry of Benzidine
Authors: Hodgson H. H. 
Published: July 2010

Summary.This paper deals with—

The substantive character of disazo‐dyestuffs from benzidine and its derivatives.
The diphenyl problem.
The Cain isomerism.
Isomeric benzerythrenes.
Preparation of 4‐chloro‐3‐nitroaniline and the violent explosiveness of its diazonium sulphate.
Preparation of 4: 4′‐dichloro‐3: 5′‐di‐nitrodiphenyl.
The nitration of diphthalylbenzidine.
Colour and Constitution. Part VIII–Some Colour Problems from the Viewpoint of Resonance Theory*
Authors: HODGSON H. H. 
Published: July 2010

SummaryH. E. Armstrong's quinonoid and triple colour‐centre hypotheses are discussed from the standpoint of modern resonance theory, on which the quinonoid system is only one type of oscillating system which can exhibit resonance. The older theory fails completely to explain the colours of the aliphatic nitrosocompounds and of the absence of colour in pp′‐quinonediimine, as well as the enhanced colour of quinhydrone. The earlier attempts, however, laid the foundation for the later quasi‐quantitative theory. That Armstrong should take iodoform as a reference substance in his wider generalisation indicated beyond doubt the necessity for a theory such as that provided by the concept of resonance.