bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abnormal cholinergic and GABAergic vascular innervation in the hypothalamic arcuate nucleus of obese tub/tub mice
Authors: Bäckberg Matilda , Meister Björn 
Published: April 2004

AbstractTubby and tubby‐like proteins (TULPs) are encoded by members of a small gene family. An autosomal recessive mutation in the mouse tub gene leads to blindness, deafness, and maturity‐onset obesity. The mechanisms by which the mutation causes the obesity syndrome has not been established. We compared obese tub/tub mice and their lean littermates in order to find abnormalities within the mediobasal hypothalamus, a region intimately associated with the regulation of body weight. Using an antiserum to the vesicular acetylcholine transporter (VAChT), a marker for cholinergic neurons, many unusually large VAChT‐immunoreactive (‐ir) nerve terminals, identified by colocalization with the synaptic vesicle protein synaptophysin, were demonstrated in the hypothalamic arcuate nucleus of obese tub/tub mice. Double‐labeling showed that VAChT‐ir nerve endings also contained glutamic acid decarboxylase (GAD), a marker for γ‐aminobutyric acid (GABA) neurons. The VAChT‐ and GAD‐ir nerve terminals were in close contact with blood vessels, identified with antisera to platelet endothelial cell adhesion molecule‐1 (PECAM; also called CD31), laminin, smooth muscle actin (SMA), and glucose transporter‐1 (GLUT1). Such large cholinergic and GABAergic nerve terminals surrounding blood vessels were not seen in the arcuate nucleus of lean tub/+ mice. The presence of abnormal cholinergic/GABAergic vascular innervation in the arcuate nucleus suggests that alterations in this region, which contains neurons that receive information from the periphery and which relays information about the energy status to other parts of the brain, may be central in the development of the obese phenotype in animals with an autosomal recessive mutation in the tub gene. Synapse 52:245–257, 2004. © 2004 Wiley‐Liss, Inc.
INO® – Oberflächentechnik im Internet. INO® – Surface – Technology in the WWW
Authors: Petrik Marko , Brand Jochen , Schiffmann Kirsten , Fetzer Hans‐Jochen , Gemmler Armin , Schwarz Stefan , Griepentrog Michael , Reiners Georg 
Published: April 2004

AbstractIn den letzten Jahren wurde eine Menge Forschungsarbeit auf dem Gebiet der Oberflächen‐ und Dünnschichttechnologie geleistet, oftmals gefördert durch staatliche Forschungsprogramme, wie zum Beispiel durch das Forschungsprogramm “OSTec”.Aber die Übertragung dieser großen Menge Wissens in industrielle Anwendungen ist noch ein Problem, weil der Zugang zu diesem Wissen für die Öffentlichkeit oft mit Hindernissen verbunden ist. Es ist kaum möglich einen Überblick zu behalten über alle neuen Entwicklungen. Um dieses Problem zu lösen ist ein neues internetbasiertes Informationssystem entwickelt worden (www.schichttechnik.net).Es beinhaltet das gesammelte Wissen des “OSTec” – Programms der letzen 10 Jahre und die Daten von Produkten kommerzieller Beschichter. INO® macht das Wissen einer breiten Öffentlichkeit zugänglich.
Rural poverty, household responses to shocks, and agricultural land use: panel results for El Salvador
Authors: RODRÍGUEZ-MEZA JORGE , SOUTHGATE DOUGLAS , GONZÁLEZ-VEGA CLAUDIO 
Published: April 2004

This paper addresses factors influencing agricultural land use in rural households in El Salvador, with particular attention paid to the effects of income. Two linkages between the area a household farms and income per capita are critical. First, there is a precautionary demand for land that can be used for subsistence agriculture and this demand declines as income rises. Second, the area a household is able to farm goes up as income increases. Together, these two linkages imply that the relationship between agricultural land use and per capita income takes the shape of an Environmental Kuznets Curve (EKC).Using panel data collected since 1995 in four biennial surveys of a nationally representative sample of rural households, we have analyzed agricultural land use at the household level. Evidence of an EKC relating farmed area to per capita income has been obtained. In addition, other factors influencing a household's use of natural resources have been examined.
BLACK HEARTS AND MONSTERS OF THE MIND: RACE AND IDENTITY IN ANTEBELLUM AMERICA
Authors: FREDRICKSON GEORGE M. 
Published: April 2004

Bruce Dain, A Hideous Monster of the Mind: American Race Theory in the Early Republic (Cambridge, MA: Harvard University Press, 2002)Patrick Rael, Black Identity and Black Protest in the Antebellum North (Chapel Hill, NC: University of North Carolina Press, 2002)John Stauffer, The Black Hearts of Men: Radical Abolitionism and the Transformation of Race (Cambridge, MA: Harvard University Press, 2002)
JESUS MATTERS IN THE USA
Authors: HOLLINGER DAVID A. 
Published: April 2004

Eugene McCarraher, Christian Critics: Religion and the Impasse in Modern American Social Thought (Ithaca, NY: Cornell University Press, 2000)D. G. Hart, The Lost Soul of American Protestantism (Lanham, MD: Rowman & Littlefield, 2002)William R. Hutchison, Religious Pluralism in America: The Contentious History of a Founding Ideal (New Haven, CT: Yale University Press, 2003)John T. McGreevy, Catholicism and American Freedom: A History (New York: W. W. Norton, 2003)
Understanding and Improving NADPH‐Dependent Reactions by Nongrowing Escherichia coli Cells
Authors: Walton Adam Z. , Stewart Jon D. 
Published: April 2004

AbstractWe have shown that whole Escherichia coli cells overexpressing NADPH‐dependent cyclohexanone monooxygenase carry out a model Baeyer‐Villiger oxidation with high volumetric productivity (0.79 g ϵ‐caprolactone/L·h ) under nongrowing conditions (Walton, A. Z.; Stewart, J. D. Biotechnol. Prog. 2002, 18, 262–268). This is approximately 20‐fold higher than the space‐time yield for reactions that used growing cells of the same strain. Here, we show that the intracellular stability of cyclohexanone monooxygenase and the rate of substrate transport across the cell membrane were the key limitations on the overall reaction duration and rate, respectively. Directly measuring the levels of intracellular nicotinamide cofactors under bioprocess conditions suggested that E. coli cells could support even more efficient NADPH‐dependent bioconversions if a more suitable enzyme‐substrate pair were identified. This was demonstrated by reducing ethyl acetoacetate with whole cells of an E. coli strain that overexpressed an NADPH‐dependent, short‐chain dehydrogenase from bakerapos;s yeast ( Saccharomyces cerevisiae). Under glucose‐fed, nongrowing conditions, this reduction proceeded with a space‐time yield of 2.0 g/L·h and a final product titer of 15.8 g/L using a biocatalyst:substrate ratio (g/g) of only 0.37. These values are significantly higher than those obtained previously. Moreover, the stoichiometry linking ketone reduction and glucose consumption (2.3 ± 0.1) suggested that the citric acid cycle supplied the bulk of the intracellular NADPH under our process conditions. This information can be used to improve the efficiency of glucose utilization even further by metabolic engineering strategies that increase carbon flux through the pentose phosphate pathway.
A Facile and Efficient Method To Achieve LacZ Overproduction by the Expression Vector Carrying the Thermoregulated Promoter and Plasmid Copy Number
Authors: Chao Yun‐Peng , Wen Chih‐Sheng , Wang Jen‐You 
Published: April 2004

AbstractOn the basis of the runaway‐replication vector, an expression plasmid was developed to achieve tight regulation as well as high‐level expression of cloned genes by thermal control of the promoter together with the plasmid copy number. To demonstrate the feasibility of this approach, the lacZ gene was fused with the heat‐inducible promoter on the vector, and the result showed that protein production levels in the Escherichia coli strain harboring the recombinant plasmid could be varied in response to various degrees of heat shock. The maximal soluble LacZ ranging between 45 000 and 50 000 Miller units was obtained as the recombinant strain received a 30 → 40 °C stepwise upshift, and it accounted for a 450‐fold amplification over an uninduced level. Further analyses by SDS‐PAGE indicated the maximal protein production (including soluble and insoluble forms) in the bacteria reaching approximately 30% total cell protein. In addition, two approaches were demonstrated to be very useful in enhancing the total soluble LacZ production on a fermenter scale. One was to shuttle the culture between two fermenters connected in series and set at different temperatures. The other resorted to the use of two‐step temperature alteration in a batch fermenter, namely, raising the temperature to 40 °C for a certain period of time followed by reducing the temperature to 37 °C. Overall, it illustrates the remarkable features of the expression system with stringent regulation, high‐level production capacity, facile induction, and high stability, and the usefulness of this system for recombinant protein productions is promising.
Catalytic Properties of d‐Amino Acid Oxidase in Cephalosporin C Bioconversion: A Comparison between Proteins from Different Sources
Authors: Pollegioni Loredano , Caldinelli Laura , Molla Gianluca , Sacchi Silvia , Pilone Mirella S. 
Published: April 2004

AbstractLacking an efficient process to produce 7‐aminocephalosporanic acid from cephalosporin C in a single step, d‐amino acid oxidase (DAAO) is of foremost importance in the industrial, two‐step process used for this purpose. We report a detailed study on the catalytic properties of the three available DAAOs, namely, a mammalian DAAO and two others from yeast ( Rhodotorula gracilisand Trigonopsis variabilis). In comparing the kinetic parameters determined for the three DAAOs, with both cephalosporin C and d‐alanine as substrate, the catalytic efficiency of the two enzymes from microorganism is at least 2 orders of magnitude higher than that of pig kidney DAAO. Furthermore, the mammalian enzyme is more sensitive to product inhibition (from hydrogen peroxide and glutaryl‐7‐aminocephalosporanic acid). Therefore, enzymes from microorganisms appear to be by far more suitable catalysts for bioconversion, although some different minor differences are present between them (e.g., a higher activity of the R. gracilisenzyme when the bioconversion is carried out at saturating oxygen concentration). The mammalian DAAO, even being a poor catalyst, is more stable with respect to temperature than the R. gracilis enzyme in the free form. In any case, for industrial purposes DAAO is used only in the immobilized form where a strong enzyme stabilization occurs.
Maximizing Recovery of Native Protein from Aggregates by Optimizing Pressure Treatment
Authors: Lefebvre Brian G. , Gage Matthew J. , Robinson Anne Skaja 
Published: April 2004

AbstractRecovering native protein from aggregates is a common obstacle in the production of recombinant proteins. Recent reports have shown that hydrostatic pressure is an attractive alternative to traditional denature‐and‐dilute techniques, both in terms of yield and process simplicity. To determine the effect of process variables, we subjected tailspike aggregates to a variety of pressure‐treatment conditions. Maximum native tailspike yields were obtained with only short pressure incubations (<5 min) at 240 MPa. However, some tailspike aggregates were resistant to pressure, despite multiple cycles of pressure. Extending the postpressure incubation time to 4 days improved the yield of native protein from aggregates from 19.4 ± 0.9 to 47.4 ± 19.6 μg/mL (approximately 78% yield of native trimer from nonaggregate material). The nearly exclusive conversion of monomer to trimer over the time scale of days, when combined with previous kinetic data, allows for the identification of three postpressure kinetic phases: a rapid phase consisting of structured dimer conversion to trimer (30 min), an intermediate phase consisting of monomer conversion to aggregate (100 min), and a slow phase consisting of conversion of monomer to trimer (days). Optimizing the production of structured dimer can yield the highest level of folded protein. Typical refolding additives, such as glycerol, or low‐temperature incubation did not improve yields.
Incorporation of 3T3‐L1 Cells To Mimic Bioaccumulation in a Microscale Cell Culture Analog Device for Toxicity Studies
Authors: Viravaidya Kwanchanok , Shuler Michael L. 
Published: April 2004

AbstractDeficiencies in the early ADMET (absorption, distribution, metabolism, elimination, and toxicity) information on drug candidates extract a significant economic penalty on pharmaceutical firms. We have developed a microscale cell culture analog (μCCA) device that can potentially provide better, faster, and more efficient prediction of human and animal responses to a wide range of chemicals. The system described in this paper is a simple four‐chamber μCCA (“lung”–“liver”–“fat”–“other tissue”) designed on the basis of a physiologically based pharmacokinetics (PBPK) model of a rat. Cultures of L2, HepG2/C3A, and differentiated 3T3‐L1 adipocytes were selected to mimic the key functions of the lung, liver, and fat compartments, respectively. Here, we have demonstrated the application of the μCCA system to study bioaccumulation, distribution, and toxicity of selected compounds. Results from the bioaccumulation study reveal that hydrophobic compounds such as fluoranthene preferentially accumulated in the fat chamber. Only a small amount of fluoranthene was observed in the liver and lung chambers. In addition, the presence of the differentiated 3T3‐L1 adipocytes in the μCCA device significantly reduced naphthalene and naphthoquinone‐induced glutathione (GSH) depletion. These findings suggest the potential utilization of the μCCA system to assess ADMET characteristics of the compound of interest prior to animal or human trials.
Hydrolysis of Nonstarch Carbohydrates of Wheat‐Starch Effluent for Ethanol Production
Authors: Palmarola‐Adrados Beatriz , Juhász Tamás , Galbe Mats , Zacchi Guido 
Published: April 2004

AbstractA (polysaccharide‐rich) waste stream derived from a combined starch and ethanol factory was investigated regarding hydrolysis of the nonstarch carbohydrates for ethanol production. The material was characterized and processed to yield the maximum amount of sugars. The starch fraction was hydrolyzed with amylolytic enzymes, and the resulting fibrous material was separated by filtration. This material, denoted starch‐free fibers (SFF), was subjected to heat treatment followed by enzymatic hydrolysis to recover the other major carbohydrate components, namely, cellulose and hemicellulose, in monomeric form. Heat treatment in a microwave oven efficiently solubilized a fraction of these polysaccharides and made the material more accessible to the cellulolytic and hemicellulolytic enzymes used in the subsequent enzymatic hydrolysis. The maximum sugar yield after enzymatic hydrolysis, achieved with pretreatment at 170 °C for 40 min, was 34.1 g per 100 g SFF, comprising 12.8 g glucose, 13.9 g xylose and 7.4 g arabinose, corresponding to 66%, 71% and 51% of the theoretical, respectively.
Determination of Viable Yeast Cells by Gravitational Field‐Flow Fractionation with Fluorescence Detection
Authors: Sanz R. , Galceran M. T. , Puignou L. 
Published: April 2004

AbstractVinification processing is largely related to yeast performance and depends on the initial cell viability. To optimize the quality of wine fermentation, control of the yeast quality is mandatory. The present paper describes a new method using gravitational field flow fractionation (GrFFF) with fluorescence detection for the determination of yeast cell viability before the fermentation process. A GrFFF calibration procedure was developed using commercial yeast to prepare standards of viable cells and propidium iodide (PI) as fluorescent probe for nonviable cells. The suitability of the new method was tested with several commercial yeast strains with a g/L content ranging from 1 to 3. The validation of the method was performed by comparing GrFFF viability values with those obtained using Coulter counter and flow cytometry techniques.
Interaction of a novel dihydropyridine K+ channel opener, A‐312110, with recombinant sulphonylurea receptors and KATP channels: comparison with the cyanoguanidine P1075
Authors: Felsch Holger , Lange Ulf , Hambrock Annette , Löffler‐Walz Cornelia , Russ Ulrich , Carroll William A , Gopalakrishnan Murali , Quast Ulrich 
Published: April 2004

ATP‐sensitive K+ channels (KATP channels) are composed of pore‐forming subunits (Kir6.x) and of regulatory subunits, the sulphonylurea receptors (SURx). Synthetic openers of KATP channels form a chemically heterogeneous class of compounds that are of interest in several therapeutic areas. We have investigated the interaction of a novel dihydropyridine opener, A‐312110 ((9R)‐9‐(4‐fluoro‐3‐iodophenyl)‐2,3,5,9‐tetrahydro‐4H‐pyrano[3,4‐b]thieno [2,3‐e]pyridin‐8(7H)‐one‐1,1‐dioxide), with SURs and Kir6/SUR channels in comparison to the cyanoguanidine opener P1075.
In the presence of 1 mM MgATP, A‐312110 bound to SUR2A (the SUR in cardiac and skeletal muscle) and to SUR2B (smooth muscle) with Ki values of 14 and 18 nM; the corresponding values for P1075 were 16 and 9 nM, respectively. Decreasing the MgATP concentration reduced the affinity of A312110 binding to SUR2A significantly more than that to SUR2B; for P1075, the converse was true. At SUR1 (pancreatic β‐cell), both openers showed little binding up to 100 μM.
In the presence of MgATP, both openers inhibited [3H]glibenclamide binding to the SUR2 subtypes in a biphasic manner. In the absence of MgATP, the high‐affinity component of the inhibition curves was absent.
In inside‐out patches, the two openers activated the Kir6.2/SUR2A and Kir6.2/SUR2B channels with similar potency (∼50 nM). Both were almost 2 × more efficacious in opening the Kir6.2/SUR2B than the Kir6.2/SUR2A channel.
The results show that the novel dihydropyridine A‐312110 is a potent KATP channel opener with binding and channel‐opening properties similar to those of P1075.

British Journal of Pharmacology (2004) 141, 1098–1105. doi:10.1038/sj.bjp.0705718
4‐Bromo‐2,5‐dimethoxyphenethylamine (2C‐B) and structurally related phenylethylamines are potent 5‐HT2A receptor antagonists in Xenopus laevis oocytes
Authors: Villalobos Claudio A , Bull Paulina , Sáez Patricio , Cassels Bruce K , Huidobro‐Toro J Pablo 
Published: April 2004

We recently described that several 2‐(2,5‐dimethoxy‐4‐substituted phenyl)ethylamines (PEAs), including 4‐I=2C‐I, 4‐Br=2C‐B, and 4‐CH3=2C‐D analogs, are partial agonists at 5‐HT2C receptors, and show low or even negligible intrinsic efficacy at 5‐HT2A receptors. These results raised the proposal that these drugs may act as 5‐HT2 antagonists.
To test this hypothesis, Xenopus laevis oocytes were microinjected with the rat clones for 5‐HT2A or 5‐HT2C receptors. The above‐mentioned PEAs and its 4‐H analog (2C‐H) blocked the 5‐HT‐induced currents at 5‐HT2A, but not at the 5‐HT2C receptor, revealing 5‐HT2 receptor subtype selectivity. The 5‐HT2A receptor antagonism required a 2‐min preincubation to attain maximum inhibition.
All PEAs tested shifted the 5‐HT concentration–response curves to the right and downward. Their potencies varied with the nature of the C(4) substituent; the relative rank order of their 5‐HT2A receptor antagonist potency was 2C‐I>2C‐B>2C‐D>2C‐H.
The present results demonstrate that in X. laevis oocytes, a series of 2,5‐dimethoxy‐4‐substituted PEAs blocked the 5‐HT2A but not the 5‐HT2C receptor‐mediated responses. As an alternative hypothesis, we suggest that the psychostimulant activity of the PEAs may not be exclusively associated with partial or full 5‐HT2A receptor agonism.

British Journal of Pharmacology (2004) 141, 1167–1174. doi:10.1038/sj.bjp.0705722
In vitro coronary artery imaging with sixteen‐slice helical computed tomography
Authors: Knollmann F. , Yankah C. A. , Kaisers U. , Felix R. 
Published: April 2004

Purpose: To determine the benefits of submillimeter coronary computed tomography (CT) angiography in vitro. Material and Methods: The coronary arteries of three domestic pigs were filled with contrast agent and depicted with clinically applicable CT angiography protocols with a slice thickness of 0.63 to 2.5 mm. Results: With 2.5 mm slices, only the third‐degree coronary artery branches could be discerned. With 1.25 mm slices, some fourth‐degree branches of the right coronary artery could be discerned upon maximum intensity projections. With 0.63 mm slices, fourth‐degree coronary artery branches could be discerned in all locations. Conclusion: The introduction of 16‐row detector CT with submillimeter z‐axis resolution translates into an order‐of‐magnitude benefit for the depiction of coronary artery branches.
Comparable ultrasound measurements of ten anatomical specimens of infant hip joints by the methods of graf and terjesen
Authors: Falliner A. , Hahne H.‐J. , Hedderich J. , Brossmann J. , Hassenpflug J. 
Published: April 2004

Purpose: To define which sonographic section planes relative to the acetabular inlet plane will produce analyzable images with the methods of Graf and Terjesen. Material and Methods: Anatomical specimens of infant hip joints were investigated in a water bath using the methods of Graf and Terjesen. Acetabular position was varied in defined increments with respect to the ultrasound beam. The alpha angles and the femoral head coverage (FHC) were measured. Results: To obtain images analyzable by the two methods, the ultrasound beam had to intersect with the acetabular inlet plane at defined angles. The acetabular notch had to be anteriorly rotated from the ultrasound beam plane by at least 20°. Beam entry within a 50° sector posterior to the perpendicular on the inlet plane resulted in analyzable images. The stepwise multiple linear regression analysis showed that alpha angles and FHC were much affected by the coronal‐plane transducer tilt. Conclusions: The fact that caudal tilts of the transducer are associated with reduced alpha angles and FHC values should be kept in mind in clinical ultrasound investigations. It is recommended that the transducer should be put on the greater trochanter perpendicular to the transverse axis of the body.
Limitations of quantitative bone‐mass measurements using assessments of first‐order statistics of grey‐level histograms in plain radiographs
Authors: Kouloulias V. E. , Matsopoulos G. , Kouvaris J. R. , Antypas C. , Uzunoglu N. C. , Varela M. N. , Metafa A. , Sandilos P. , Vlahos L. J. 
Published: April 2004

Purpose: To evaluate the quality assurance of image‐processing techniques in plain radiographs of skeletal structures. Material and Methods: Twenty‐two patients were studied, each with one osteolytic metastasis. Accuracy and precision of tube voltage and timer were confirmed. The mean value of grey‐level histograms in plain radiographs (MVGLHs) was assessed. The deviation was monitored after five sets of sequential X‐rays retaining the same settings for each radiograph. Results: Deviation was significantly higher in anatomical areas of thorax (21.2%) and abdomen (42.4%), while the consistency of MVGLH for weight‐bearing bones was satisfactory with a maximum deviation of 2.9% ( P<0.001, Kruskal‐Wallis test). Conclusion: Assessment of MVGLH in plain radiographs is a reliable method for the extremities and generally for regions without superimposed movable tissues.