bluuebunny/crossref_metadata_2025 huggingface dataset:
“Truth and Taxes”
Authors: McNairn Jeffrey L.
Published: January 2021

Part of the roundtable on E. A. Heaman’s Macdonald prize-winning Tax, Order, and Good Government, this essay takes up the book’s claim to offer a social history of knowledge. It explores the central role knowledge production plays in the book to speak to current anxieties in our “post-truth” moment. It suggests that the book can be read as a neo-progressive intervention that refurbishes and updates the progressive historians of the early twentieth century. As a result, this brilliant book twins a rather naturalistic conception of self-interest with a deep commitment to thinking historically about social injustice, power, and the conditions by which truth might replace ignorance.
Comment on Padraic X. Scanlan, Freedom’s Debtors: British Antislavery in Sierra Leone in the Age of Revolution
Authors: Rogers Nicholas
Published: January 2021

Padraic Scanlan’s Freedom’s Debtors makes an important intervention in the debate on the abolition of slavery by looking at what actually happened in Sierra Leone as it moved from company project to crown colony. Scanlan shows that anti-slavery advocates were not in practice equity advocates: slaves had to earn their freedom. In so doing he forces us to reconsider the manifold forms of bonded labour that characterised the Atlantic world and the imperatives of a globalizing market that demanded the continuing production of tropical staples by captive workforces, before and after slavery. Scanlan arguably blends abolition and emancipation in the opening phase of the British campaign to end the slave trade, but he shows, despite the humanitarian motives of some activists, that the full emancipation for slaves was conditional on their integration into global political economies.
The Abolition of the British Slave Trade Seen from Sierra Leone: Padraic Scanlan’s Freedom’s Debtors: British Antislavery in Sierra Leone in the Age of Revolution
Authors: Elbourne Elizabeth
Published: January 2021

This essay discusses the important contributions of Padraic Scanlan’s book Freedom’s Debtors: British Antislavery in Sierra Leone in the Age of Revolution, to the history of the abolition of the slave trade in the British empire. Scanlan’s innovative work emphasizes material concerns rather than altruism in explaining how policing the slave trade in West Africa and attempting to control the formerly enslaved, not least in redeploying them as soldiers, worked to the advantage of colonial administrators and British elites.  The essay examines Scanlan’s work in relation to the economic history of abolition, the history of humanitarianism, the entanglement of abolition and imperialism in West Africa, and the military history of empire, which Scanlan vitally puts back into conversation with the history of abolition.  It also asks how to include religion as a motivating force, and suggests that the book may undervalue the role of religious belief, not least among Africans.  As Scanlan’s evidence shows, the line between freedom and unfreedom was by no means sharp. Debates about the post-abolition economy were accordingly informed by anxieties about the meaning of “freedom”, as ideological beliefs informed economic conceptions.  Freedom’s Debtors demonstrates how events in Sierra Leone anticipated the fusion of humanitarianism and colonialism that was crucial to justifying empire in West Africa and underscores the vital importance of understanding abolition in terms of how it worked on the ground rather than solely how it was thought about in Britain.
Revisiting Freedom’s Debtors
Authors: Scanlan Padraic X.
Published: January 2021

This essay reconsiders Freedom’s Debtors through the lens of the three Ferguson Prize panelists’ comments. It frames the arguments of the book in relationship to a growing body of scholarship on the history of Sierra Leone, and in relationship to older problems in the history of British imperial political economy. The essay reasserts two of the core contentions in Freedom’s Debtors: the close, and sometimes unacknowledged, proximity between British slavery and British antislavery, and the centrality of antislavery to British imperial expansion in the nineteenth century.
Relationship between grammatical and pragmatic competence in EFL of Spanish learners through a computer adaptive test
Authors: Martín Marchante Beatriz
Published: January 2021

The work at hand is part of a wider study by Martín-Marchante (2015), the objective of which was to study the way pragmatics assessment is approached in the Oxford Online Placement Test (OOPT) which is, currently, one of the most profusely administered computer adaptive tests (CAT). This paper aims, now, to find out the degree of difficulty of the pragmatic items in the OOPT and how much importance is given to pragmatic competence in this test. Furthermore, we analyze the relationship between grammatical and pragmatic competence in EFL of a group of Spanish un- dergraduate students, who took this test. To this end, a descriptive analysis and a multiple linear regression analysis was carried out. The results showed that the quality of the pragmatic items in the OOPT could be improved. Also, we have found that the pragmatic items were somehow related to the student’s final score but not so much as other items of the test, such as those related to gram- mar and reading comprehension. Additionally, the results indicated that there was no correlation between the grammatical and the pragmatic competence of this group of students.
Testing of Journal Writing for Symptom Concordance in Adults with Multiple Sclerosis
Authors: Newland Pamela , Bettencourt B. Ann , Schares Sarah , Hendricks-Ferguson Verna
Published: January 2021

Background:

Adults with multiple sclerosis (MS) experience many complex symptoms. However, research is lacking on the best method to record their symptom experience. The primary goal of this study was to test the feasibility of journal writing to capture the description of core symptoms experienced by adults with MS. A secondary goal was to collect self-report symptom data to assess concordance between the journal entries and MS-Related Symptom Checklist (MS-RS) scores.

Methods:

A preselected group of participants (n = 5) from the total sample of 16 participants with MS were asked to complete the revised MS-RS and Web-based journal writing for 20 minutes per day for 4 consecutive days over a 4-week period. Feasibility was evaluated by journal completion rates.

Results:

Most participants found journal writing acceptable as a method for writing about symptoms. Participants were able to write about symptoms that formed clusters: unpredictable physical alterations and unpredictable sensory and emotional changes. Likewise, participants reported frequent fatigue, difficulty sleeping, heat intolerance, and difficulty concentrating/cognitive problems from the revised MS-RS. Disconcordance between revised MS-RS data and journal entries included lack of disclosure of difficulty sleeping and “pins and needles” in the journals.

Conclusions:

Preliminary findings from this study provide the personal perspectives of core symptoms experienced by adults with MS. These results provide preliminary evidence of the feasibility of journal writing, along with self-report survey, to describe symptoms in adults with MS.
Assessment of Cerebrovascular Dynamics and Cognitive Function with Acute Aerobic Exercise in Persons with Multiple Sclerosis
Authors: Lefferts Wesley K. , Rosenberg Alexander J. , Schroeder Elizabeth C. , Grigoriadis Georgios , Sandroff Brian M. , Motl Robert W. , Baynard Tracy
Published: January 2021

Background:

Cognitive dysfunction in multiple sclerosis (MS) may partially stem from inadequate cerebral blood flow. Cerebral blood flow and cognitive function improve with aerobic exercise in healthy adults. The effect of aerobic exercise on cerebrovascular hemodynamics and cognitive performance in persons with MS is unclear. The acute effect of aerobic exercise versus quiet rest on cerebrovascular hemodynamics and cognitive performance in relapsing-remitting MS was examined.

Methods:

Sixteen adults with relapsing-remitting MS underwent cerebrovascular hemodynamics and cognitive performance testing before, 2 minutes after, and 30 minutes after aerobic exercise (20-minute treadmill walking, 60% peak oxygen consumption) and a time-matched seated control. Brachial blood pressure was obtained via an oscillometric cuff. Right middle cerebral artery (MCA) blood velocity was measured via transcranial Doppler and used to calculate mean velocity, pulsatility index (PI), and conductance. Carotid artery stiffness was measured via ultrasonography and tonometry. Cognitive performance (accuracy, reaction time) was assessed using a modified flanker task.

Results:

Exercise elicited significant increases in mean pressure and carotid artery stiffness and decreases in MCA conductance at 2 minutes after exercise, which subsided by 30 minutes (P < .05). Exercise did not significantly alter MCA PI. Flanker reaction time decreased during posttesting in both conditions (P < .05). There were no condition × time interactions for cognitive performance.

Conclusions:

Persons with MS seem resilient to exercise-induced acute changes in MCA PI despite transient carotid stiffening, potentially via reductions in MCA conductance. These data suggest that changes in cognitive performance after acute aerobic exercise are not directly related to transient cerebrovascular responses in persons with MS.
Las virtualidades del arte (o cómo el arte es, ante todo, virtual)
Authors: Ruiz José Manuel
Published: January 2021

Virtual deriva del latín virtus: ‘poder, facultad, fuerza, virtud’. Hoy es un término empleado para referirse a aquello que reproduce la experiencia de la realidad en el medio digital. En el espacio del arte, por su parte, se denomina arte virtual a aquellas obras fruto de la interacción multimedia hombre-máquina desarrolladas mediante tecnología de realidad virtual. Pero virtual es el principal nombre del Ser en la obra del filósofo francés Gilles Deleuze. No tiene relación alguna con lo ilusorio o lo falso, por lo que existiría una deformación colectiva del concepto, un malentendido integral heredado del mundo tecnológico y del marketing empresarial. Este trabajo pretende retomar lo virtual deleuziano para trasladarlo desde el campo filosófico hacia el espacio del arte y demostrar su relación. Se ha empleado una metodología cualitativa basada en la literatura comparada que ha partido de la exégesis como método para afrontar la definición de lo virtual hasta llegar a la eiségesis en el corpus concerniente a las virtualidades del arte. Se concluye que la potencialidad de la obra de arte reside en su capacidad de generar virtualidades. Lo virtual es el lugar del enigma, la potencia de ilusión, verdadera estrategia del arte. La obra de arte es el problema, el arte es el conjunto problemático. Lo virtual es el fundamento del arte. El arte es, fundamentalmente, virtual.
El trauma de lo inerte. Apuntes para una nueva parasitología
Authors: Flores Arancibia Ivan , Saez Tajafuerce Begonya
Published: January 2021

En el contexto de una crisis ecológica que amenaza el destino de las especies que pueblan la Tierra, incluida la humana, la pandemia causada por el virus SARS-CoV-2 cae en un mundo en extinción. Esto nos obliga a revisar el discurso parasitológico contemporáneo que no ha dejado de articular la lógica del intruso basándose en una concepción afirmativa o incluso bondadosa del parásito. Sean cuales sean los modos de infección parasitaria, una inconfesada dialéctica evolutiva conserva el futuro de lo viviente. Pero si planteamos como originaria la intrusión del parásito y la economía parasitaria como estructural poniendo el énfasis en su negatividad constitutiva, su apertura al futuro debe ser considerada como destitución de todo porvenir. En este planteamiento, lo inerte viene a dar cuenta de dicha negatividad constitutiva en calidad de resto latente que procede como materialización de la contingencia, afectando irreversiblemente al tiempo y a su vivencia, y constituye, de ese modo, un trauma para el mundo y para la vida; el trauma de lo humano que muta para extinguirse.
Analytical solution of magneto-mechanical magnetic dipole model for metal magnetic memory method
Authors: Shi Peng-Peng , Hao Shuai ,   Institute of Mechanics and Technology, School of Civil Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China
Published: January 2021

Magnetic dipole theory has been widely and successfully used to explain the leakage magnetic field signals. Because the model parameter such as magnetic dipole density is not easy to quantify, magnetic dipole theory often needs normalizing in application, which is considered to be unsuitable for quantitatively analyzing the magnetic memory signals with the stress effect. In this paper, the theoretical model of magneto-mechanical coupling magnetic dipole is established, which is suitable for analyzing the stress effect on magnetic signals in magnetic memory testing method. Based on the ferromagnetic theory, the equivalent field under the combined action of the applied load and the magnetic field is determined. And then, the magneto-mechanical analytical model is obtained for the isotropic ferromagnetic material under the weak magnetic field based on the first-order magnetization approximation in the weak magnetization state. Under the assumptions of rectangular and V-shaped magnetic charge distribution for the two-dimensional magnetic signal problem, the theoretical analytical models of the magnetic memory signals from the smooth and cracked specimens, and the analytical models of the magnetic memory signal induced by the rectangular and V-shaped surface defect are established. Based on the analytical solution of the proposed magneto-mechanical magnetic dipole theory, the difference in signal between before and after the failure of the specimen, the signal from the rectangular and V-shaped defect, and other influencing factors and laws of the magnetic signal are analyzed in detail. In particular, the influence of stress, environmental magnetic field, defect morphology and size, lift-off effect, specimen size and other factors on magnetic memory signals can be described based on the analytical solution of magneto-mechanical magnetic dipole models proposed in this paper. The proposed analytical model of magneto-mechanical magnetic dipole in this paper is simple and easy to use, and the present research shows that the proposed analytical solution in this paper can explain some basic experimental phenomena and laws in magnetic memory testing experiments. In addition, the precise magneto-mechanical coupling quantitative model combined with the finite element analysis method is still needed for accurately analyzing the magnetic memory signals in experiment.
The influence of rare birds on observer effort and subsequent rarity discovery in the American birdwatching community
Authors: Laney Jesse A. , Hallman Tyler A. , Curtis Jenna R. , Robinson W. Douglas
Published: January 2021

Birdwatching is a rapidly growing pastime, increasingly involving the pursuit of rare birds as birders build lists of species they encounter. We expected reports of rare bird discoveries to quickly draw birders to locations, and that the increased attention at those locations would decay over time. We hypothesized that magnitude of draw and rates of decay would vary depending on characteristics of the species and the geographic locations where rarities were discovered. Discoveries of additional rarities might affect both the draw and decay, so we also quantified empirical evidence for thePatagonia Picnic Table Effect(PPTE), a social feedback loop where rarity discoveries are presumed to lead to additional rarity discoveries because of the elevated levels of birder activity once an initial rarity is reported. Although commonly invoked, supporting evidence for the PPTE hypothesis is anecdotal. We used 10 years of eBird data (2008–2017) in the United States to (1) understand birding activity when rarities were reported and the factors associated with draw and decay, and (2) assess the frequency at which initial rarity discoveries lead to reports of additional rarities. Across 273 rarity events, birder effort, as indexed by numbers of eBird checklists, increased above the pre-event baseline level, with the magnitude of draw varying geographically. We found no indication that draw was influenced by species identity or rarity-level, but latitude and distance to small airport proved important in drawing additional eBirders to rare bird discoveries. Mean draw of rarities and mean number of checklists from the same locations prior to each rarity discovery grew through the ten years, suggesting an increased influence of eBird on birder behavior in general. Decay rates in birder effort were more gradual in rare bird events with longer durations. Effort declined below baseline-levels after rarities went undetected, suggesting, “location-fatigue” following rarity events. Results did not support the PPTE hypothesis. Controlling for site-specific circumstances, birders had no better chance of finding additional rarities during events than at times outside events. Our results emphasize that eBird checklist quantity at rarity events follows a predictable but variable pattern of draw and decay influenced by location and time since rarity discovery; that birders have statistically similar chances of finding rarities during normal “baseline” birding activities as they do when known rarities are present; and that eBird represents a largely untapped resource for studying factors that influence levels of birding activity.
Reduced Port Surgery for a Pregnant Woman With Strangulated Small Bowel Obstruction: A Case Report
Authors: Morimoto Yoshihiro , Takahashi Hidekazu , Kobayashi Teruyuki , Miyoshi Norikatsu , Haraguchi Naotsugu , Nishimura Junichi , Hata Taishi , Matsuda Chu , Mizushima Tsunekazu , Yamamoto Hirofumi , Doki Yuichiro , Mori Masaki
Published: January 2021

Introduction

Intestinal obstruction in pregnancy is very rare, but the maternal mortality rate and the fetal loss rate are high. Therefore, an early diagnosis and appropriate treatments for small bowel obstructions (SBOs) during pregnancy are crucial for the mothers and fetuses. On the other hand, laparoscopic surgeries are widely used in pregnant patients, although laparoscopic surgeries for SBOs can have higher risks of complications. Then, reduced port surgery (RPS) can reduce the risk of intestinal injury by minimizing the number of ports the operator could not control alone. There is no previous report of RPS for SBOs in pregnant patients. We report on a pregnant patient with a strangulated SBO treated with RPS without complications.

Case presentation

A 37-year-old Japanese pregnant woman complaining of severe abdominal pain was admitted by ambulance. Her gestational age was 9 weeks. Her medical history included surgery for acute perforated appendicitis and deep vein thrombosis due to anti-thrombin III deficiency. Abdominal computed tomography revealed a strangulated SBO. We performed RPS and the cause of strangulated SBO was a string at the postoperative site of the appendectomy. The ischemic region of the small bowel recovered after we cut the string and released the adhesion. The patient's postoperative course was uneventful and the fetus was not harmed.

Conclusion

This is the first report of RPS performed for the pregnant patient with the strangulated SBO. Our findings indicate that RPS is a feasible treatment for strangulated SBOs in pregnant women.
A protein kinase C inhibitory activity is present in rat brain homogenate
Authors: Schwantke Nicole , Le Peuch Christian J.
Published: July 2002

The partial purification and characterization of (a) factor(s) from rat brain which inhibit(s) the activity of calcium and phospholipid‐dependent protein kinase from the same tissue is described. This factor, present in 100000 × g rat brain homogenate supernatant, is inactivated upon treatment by trypsin and pepsin and is therefore assumed to be a protein. It was partially purified by ion‐exchange chromatography on DEAEcellulose, ammonium sulfate precipitation and gel filtration. This inhibitor is not stable to heating at 70°C for 10 min, however partial renaturation of the inhibitory activity can be observed after incubation of the denatured inhibitor for 24 h at 4°C. It is precipitable by 10% trichloroacetic acid and by 2 M ammonium sulfate. It exhibits a Stokes radius of 20 Å by gel exclusion chromatography, corresponding to a molecular mass of 20 kDa assuming a globular shape. Kinetic analysis of the inhibition of calcium‐phospholipid‐dependent histone kinase activity indicates that the inhibitor is competitive with respect to the protein substrate. No change was observed in the kinetic values of the kinase for ATP, Ca2+ and phospholipids.
Evidence for an active‐center cysteine in the SH‐proteinase α‐clostripain through use of N‐tosyl‐L‐lysine chloromethyl ketone
Authors: Gilles A.-M. , Keil B.
Published: July 2002

The rapid reaction of α‐clostripain with tosyl‐L‐lysine chloromethyl ketone results in a complete loss of activity and in the disappearance of one titratable SH group whereas the number of histidine residues is not affected. Tosyl‐L‐phenylalanine chloromethyl ketone and phenylmethylsulfonyl fluoride have no effect on the catalytic activity. From the molar ratio and under the assumption of 1:1 molar interaction, the fully active enzyme has a specific activity of 650–700 [twice the value proposed by Porter et al. (J. Biol. Chem. 246 (1971) 7675‐7682)]. Partial oxidation makes it experimentally impossible to attain this maximal value.
Cortisone‐induced small RNP tightly bound to chromatin
Authors: Konstantinova I.M. , Turoverova L.V. , Petukhova O.A. , Vorob'ev V.I.
Published: July 2002

Small nuclear RNP
Chromatin
Cortisone induction
Small RNA
Hormone acceptor
Cooperative effects in the binding of pyridoxal 5′‐phosphate to mitochondrial apo‐aspartate aminotransferase
Authors: Garzillo A.M. , Marino G. , Pispisa B.
Published: July 2002

Titrations of mitochondrial apo‐aspartate aminotransferase with pyridoxal 5′‐phosphate in the presence of AMP, contrary to what has been observed in the case of the cytosolic isoenzyme [(1983) FEBS Lett. 153, 98–102], show sigmoidal isotherms, with Hill coefficients ranging from n
H = 1.4, in the absence of AMP, to n
H = 1.8, in the presence of 5.9 mM AMP. The experimental data were successfully fitted by the Monod‐Wyman‐Changeaux model. The best fit, in the absence of AMP, was obtained with L = 30, K
R = 4.72 × 10−7 M and K
T = 1.18 × 10−5 M. Binding curves in the presence of AMP fit the model by keeping K
R as a constant. This implies that AMP could bind to the apoenzyme only in the T state. In contrast, binding curves in the presence of phosphate ion (Pi) showed a less pronounced cooperativity, the Hill coefficient dropping to n
H = 1.0 in the presence of 0.1 mM Pi. The above results suggest a regulatory role of AMP and Pi in the reconstitution of aspartate aminotransferase.
Collagen cross‐links: location of pyridinoline in type I collagen
Authors: Light Nicholas , Bailey Allen J.
Published: July 2002

Collagen from bone, dentine and tendon (type I), all of which contain the pyridinoline cross‐link at varying levels, were each digested with CNBr. The resulting peptide mixtures were resolved by gel filtration on A 1.5m agarose and assayed for pyridinoline. The polymeric cross‐linked peptide complex, polyαlCB6 [(1980) Biochem. J. 189, 111] isolated from each of these tissues did not contain pyridinoline. Only one peptide fraction contained the pyridinoline cross‐link; that identified as α2CB3,5. However, this peptide showed only a small increase in M
r in its cross‐linked form (approx. 2000–5000) demonstrating that pyridinoline is not involved in the formation of polymeric structures like polyα1CB6. These data, considered in the light of the recent finding that pyridinoline is present in type I collagens from different sources in widely varying amounts, cast doubt on its role in collagen maturation.
Specificity and mechanism of action of metal ions in yeast enolase
Authors: Brewer John M.
Published: July 2002

Enolase
Specificity
Yeast
The involvement of calcium in the stimulation of respiration in isolated rat hepatocytes by adrenergic agonists and glucagon
Authors: Crompton Martin , Goldstone Timothy P.
Published: July 2002

The effects of adrenergic agonists and glucagon on respiration and cytosolic free Ca2+ measured with quin2, in female rat hepatocytes have been compared. In the presence of lactate, all three agonists caused a permanent stimulation of respiration. However, unlike phenylephrine, glucagon induced only a transient increase in cytosolic free Ca2+ and isoprenaline caused no detectable change. Mechanisms other than Ca2+ for respiratory stimulation by cAMP‐linked agonists in liver are indicated.
Binding of gastrin to gastric transferrin
Authors: Baldwin Graham S. , Chandler Rosemary , Weinstock Janet
Published: July 2002

Binding of 125I‐gastrin2,17 to porcine gastric transferrin has been demonstrated by covalent cross‐linking with disuccinimidyl suberate. The concentration of gastrin17 required to reduce cross‐linking by 50% was approx. 100 μM. The occurrence of both gastrin and gastric transferrin in porcine gastric mucosa and lumen suggests a novel synergistic role for the observed interaction in the uptake of dietary iron.
1‐Deoxymannojirimycin inhibits Golgi‐mediated processing of glycoprotein in Xenopus oocytes
Authors: Fabbrini Maria Serena , Zoppè Monica , Bollini Roberto , Vitale Alessandro
Published: July 2002

We prepared in vitro an mRNA transcript coding for the erythroagglutinating subunit of the kidney bean glycoprotein phytohemagglutinin, E‐PHA. The mRNA, injected into Xenopus oocytes, synthesized E‐PHA carrying two Asn‐linked carbohydrate chains, one of which was processed and acquired resistance to endo‐β‐N‐acetylglucosaminidase H, as occurs in the native bean cells. When the mannose analog 1‐deoxymannojirimycin, an inhibitor of mammalian Golgi mannosidase I, was included in the oocyte culture medium, the acquisition of endo‐β‐N‐acetylglucosaminidase H resistance was abolished, indicating that also in an amphibian cell the inhibitor blocks a key reaction in Golgi‐mediated processing.
Site directed mutants of human interleukin‐1α: A 1H‐NMR and receptor binding study
Authors: Gronenborn Angela M. , Wingfield Paul T. , McDonald H.Robson , Schmeissner Ursula , Clore G.Marius
Published: July 2002

Mutant human interleukin‐1α proteins were constructed by oligonucleotide directed mutagenesis. Six different mutants were tested for receptor binding activity and showed no alteration with respect to the wild‐type protein. Analysis of these mutants by nuclear magnetic resonance spectroscopy confirmed the structural integrity of the mutant proteins and permitted the sequence specific assignment of the histidine and tryptophan residues.
Amino acid sequence of hemoglobin I from root nodules of the non‐leguminous Casuarina glauca‐Frankia symbiosis
Authors: Kortt Alexander A. , Inglis Adam S. , Fleming Anthony I. , Appleby Cyril A.
Published: July 2002

The amino acid sequence of hemoglobin I from nitrogen‐fixing root nodules of the Casuarina glauca‐Frankia symbiosis has been determined. The protein is composed of 151 amino acids including a single cysteine, a residue not found in the leghemoglobins. The molecular mass, including heme, is calculated to be 17856 Da. C. glauca hemoglobin I shows extensive sequence homology (43–52%) with other plant hemoglobins and this provides further evidence that hemoglobins from distant plant genera and animal hemoglobins share a common evolutionary origin.
The 5′‐CA DNA‐sequence preference of daunomycin
Authors: Skorobogaty Andrew , White Robin J. , Phillips Don R. , Reiss James A.
Published: July 2002

The DNA‐sequence specificity of daunomycin was investigated by DNase I footprinting and an E. coli RNA polymerase transcription‐inhibition assay. The 5′‐CA sequence was identified as being the highest affinity binding site, although other modest affinity (5′‐GC, CG, CT, TC, AC) and poor affinity sites (5′‐AA, AT, TA) were also observed. The preference of daunomycin for 5′‐CA nucleotide sequence suggests that its biological activity may arise from association with the 5′‐CA‐containing sequences thought to be associated with genetic regulatory elements in eukaryotes.
N‐terminal region of Proteus mirabilis glutathione transferase is not homologous to mammalian and plant glutathione transferases
Authors: Di Ilio C. , Aceto A. , Piccolomini R. , Allocati N. , Caccuri A.M. , Barra D. , Federici G.
Published: July 2002

The N‐terminal amino acid sequence of glutathione transferase, Pm‐GST‐6.0, purified from Proteus mirabilis [(1988) Biochem. J. 255, 971–975] up to residue 38 and a comparative peptide fingerprint are reported. No obvious homology with the sequences of alpha, pi and mu classes of mammalian glutathione transferases as well as with those of plant glutathione transferases has been noted. These results suggest that the classification so far adopted for glutathione transferases cannot be extended to the bacterial enzyme.
Structure of the α1 subunit of horse Na,K‐ATPase gene
Authors: Kano Itsu , Nagai Fumiko , Satoh Kanako , Ushiyama Keiko , Nakao Toshiko , Kano Kazutaka
Published: July 2002

Genomic DNA for Na,K‐ATPase α1 subunit was obtained from libraries of horse kidney genomic DNA in Charon 4A and in EMBL3 bacteriophages by screening with the full sized cDNA probe of the α1 subunit of rat Na,K‐ATPase as probe. The gene spans 30 kb and consists of 23 exons and 22 intervening sequences. Intron‐exon boundaries were analyzed. The protein‐coding nucleotide sequence encodes 1016 amino acids with an M
r of 112 264. The putative amino acid sequence of horse α1 is 96–97% homologous to those of other mammalian species.
Enzymatic deglycosylation of the dendrotoxin‐binding protein
Authors: Rehm Hubert
Published: July 2002

The neuronal membrane protein which binds the K+‐channel ligands dendrotoxin, mast cell degranulating peptide, and β‐bungarotoxin was purified from rat brain membranes. When analysed on 10% SDS gel electrophoresis, the purified protein contained two peptides: the toxin‐binding subunit of apparent M
r, 90 000 and another peptide of M
r, 38 000. Neuraminidase treatment reduced the M
r, of the toxin‐binding subunit to 70 000. Glycopeptidase F gave a further reduction to M
r, 65 000. In contrast, the peptide of M
r, 38 000 showed no change in M
r, upon treatment with neuraminidase and/or glycopeptidase F. It is concluded that the toxin‐binding subunit of the dendrotoxin‐binding protein, a presumptive K+ channel, is a sialated membrane protein with a peptide core of, at most, M
r, 65 000.
‘Antiflammins’: Two nonapeptide fragments of uteroglobin and lipocortin I have no phospholipase A2 ‐inhibitory and anti‐inflammatory activity
Authors: Marki F. , Pfeilschifter J. , Rink H. , Wiesenberg I.
Published: July 2002

The ‘antiflammin’ nonapeptides P1 and P2 [(1988) Nature 335, 726‐730] were synthesized and tested for inhibition of phospholipase A2 and release of prostaglandin E2, and leukotriene C4 in stimulated cells in vitro, and in vivo for anti‐inflammatory activity in rats with carrageenan‐induced paw oedema. Porcine pancreatic phospholipase A2, was not inhibited at concentrations of 0.5–50 μM. Prostaglandin E2, and leukotriene C4 release by mouse macrophages stimulated with zymosan or ATP was not affected up to a concentration of 10 μm, nor was prostaglandin release by interleukin 1β‐stimulated mesangial cells and angiotensin II‐stimulated smooth muscle cells. Both peptides exhibited no anti‐inflammatory activity in carrageenan‐induced rat paw oedema after topical (250 μg/paw) or systemic administration (1 or 4 s.c.). These results do not support the claim of potent phospholipase A2‐inhibitory and anti‐imflammatory activity of the ‘antiflammins’ P1 and P2 [1].
Carbohydrate structures of a human tissue plasminogen activator variant expressed in recombinant Chinese hamster ovary cells
Authors: Nimtz Manfred , Noll Gabriele , Pâques Eric-Paul , Conradt Harald S.
Published: July 2002

The carbohydrate structures of a genetically engineered human tissue plasminogen activator variant bearing a single N‐glycosylation site at Asn 448 are reported. After isolation of the tryptic glycopeptide and liberation of the N‐linked carbohydrates by polypeptide:N‐glycosidase F, 6 major oligosaccharide fractions were separated by HPLC on NH2‐bonded phase. Their structures were determined by compositional and methylation analyses combined with fast atom bombardment mass spectrometry. Seventy percent of the carbohydrates were of the biantennary complex type with fucose at the proximal GlcNAc and zero, one or two α2‐3 linked NeuAc. The remainder were triantennary structures with one, two or three NeuAc.
The Saccharomyces cerevisiae CDC25 gene product is a 180 kDa polypeptide and is associated with a membrane fraction
Authors: Garreau H. , Camonis J.H. , Guitton C. , Jacquet M.
Published: July 2002

In the yeast Saccharomyces cerevisiae, the CDC25 gene product is supposed to interact with ras proteins and adenylate cyclase for progression through the cell division cycle. To identify the CDC25 gene product, we raised antibodies against two hybrid proteins, encoded by in‐frame fusions between the E. coli lacZ gene and two different parts of the CDC25 gene. By protein immuno‐blotting, we were able to identify the CDC25 gene product as a 180 kDa polypeptide, which we named p180CDC25. It was detected only when the CDC25 gene was overexpressed in a proteases‐deficient yeast strain. Subcellular fractionation experiments showed that p180CDC25, as well as ras proteins, is attached to the membrane, even after treatments which release peripheral membrane proteins.
Morphological alteration of Xenopus oocytes induced by valine‐14 p21rho depend on isoprenylation and are inhibited by Clostridium botulinum C3 ADP‐ribosyltranferase
Authors: Mohr Chistiane , Just Ingo , Hall Alan , Aktories Klaus
Published: July 2002

Microinjection of the constitutively active recombinant Val‐14 p21rho A into Xenopus oocytes induced dramatic morphological changes with re‐distribution of pigments from the animal pole resulting in spotted oocytes. The effects induced by Val‐14 p21rho A were regulated by progesterone in a dose‐dependent manner whereas prior ADP‐ribosylation of the rho protein blocked its activity. About 30 min after microinjection, p21 rho was associated with the plasma membrane. The membrane association of p21rho and its biological activity were inhibited by lovastatin, an inhibitor of the 3‐hydroxy‐3‐methylglutaryl coenzyme A reductase. The findings suggest that membrane attachment and biological activity of p21rho depend on isoprenylation of the GTP‐binding protein.
Separation of two βγ subunit complexes of brain GTP‐binding proteins composed of distinct γ subunits
Authors: Asano Tomiko , Morishita Rika , Kobayashi Tamio , Kato Kanefusa
Published: July 2002

The γ subunits of GTP‐binding proteins are always associated with β subunits under physiological conditions, and at least two γ subunits exist in the brain. We report here that brain βγ subunit complexes composed of distinct γ subunits can be separated by anion exchange chromatography under nondenaturing conditions. One βγ complex was composed of a 36‐kDa β subunit and a 6‐kDa γ subunit and the other was composed of 36/35‐kDa β subunits and 4.5‐kDa γ subunit. The 6‐kDa γ subunit was phosphorylated by protein kinase C but the 4.5‐kDa γ subunit was not.
Expression of biologically active hormone‐sensitive lipase in mammalian (COS) cells
Authors: Holm Cecilia , Davis Richard C. , Fredrikson Gudrun , Belfrage Per , Schotz Michael C.
Published: July 2002

cDNAs encoding rat adipose tissue hormone‐sensitive lipase were expressed in COS cells, under the control of the SV40 promoter to half the level in rat adipocytes, the richest native source of the enzyme. A cDNA lacking most of the long 5′‐untranslated region of the full‐length rat hormone‐sensitive lipase cDNA was, with regard to the lipase activity, on the average 70% more efficiently expressed than the full‐length cDNA. The recombinant protein was almost identical to hormone‐sensitive lipase of rat adipose tissue with respect to specific activity, susceptibility to inhibitors, molecular size, phosphorylation and activation by cyclic AMP‐dependent protein kinase. The described eukaryotic expression system will allow analysis of effects of amino acid substitutions introduced into the lipase molecule by site‐directed mutagenesis.
Molybdopterin adenine dinucleotide and molybdopterin hypoxanthine dinucleotide in formylmethanofuran dehydrogenase from Methanobacterium thermoautotrophicum (Marburg)
Authors: Börner G. , Karrasch M. , Thauer R.K.
Published: July 2002

Formylmethanofuran dehydrogenase from Methanobacterium thermoautotrophicum was purified to apparent homogeneity and found to contain per mol (apparent molecular mass 110 kDa) 0.6 mol molybdenum, 4 mol non‐heme iron, 4 mol acid‐labile sulfur, in addition, 0.7 mol of a pterin‐containing co‐factor (apparent molecular mass 800 Da) which has been characterized. The pterin material was extracted after alkylation by iodoacetamide and the extract subjected to HPLC on Lichrospher 100 RP‐18. Three pterin compounds were resolved. On the basis of their UV/visible spectra and of the products formed after cleavage by nucleotide pyrophosphatase and alkaline phosphatase they were identified as the [di(carboxamidomethyl)]‐derivatives of molybdopterin guanine dinucleotide (MGD) of molybdopterin adenine dinucleotide (MAD), and of molybdopterin hypoxanthine dinucleotide (MHD). The three pterin dinucleotides were present in the proportions 1:0,4:0.1.
Expression of the N‐terminal domain of dystrophin in E. coli and demonstration of binding to F‐actin
Authors: Way M. , Pope B. , Cross R.A. , Kendrick-Jones J. , Weeds A.G.
Published: July 2002

The N‐terminal head domain of human dystrophin has been expressed in soluble form and high yield in E. coli, allowing us to test the previously unconfirmed assumption that dystrophin binds actin. DMD246, the first 246 amino acid residues of dystrophin, binds F‐actin in a strongly co‐operative manner with a Hill constant of 3.5, but does not bind G‐actin. Dystrophin heads are thus functionally competent actin‐binding proteins. This result opens the way to identifying critical residues in the actin‐binding site and encourages us that the other domains of dystrophin might also be treated as functionally autonomous modules, accessible to a similar approach.
Azidobutyryl clentiazem, a new photoactivatable diltiazem analog, labels benzothiazepine binding sites in the α1 subunit of the skeletal muscle calcium channel
Authors: Watanabe Toshiro , Kalasz Huba , Yabana Hideo , Kuniyasu Akihiko , Mershon John , Itagaki Kiyoshi , Vaghy Pal L. , Naito Kazuaki , Nakayama Hitoshi , Schwartz Arnold
Published: July 2002

[3H]Azidobutyryl clentiazem, a new photoactivatable diltiazem derivative, has a higher binding affinity than azidobutyryl diltiazem. It can be covalently incorporated into the α1 subunit of the skeletal muscle calcium channel by UV irradiation, which allows the benzothiazepine binding site to be determined. The photolabeled α1 subunit and its proteolytic fragments were analyzed with a panel of sequence‐directed antibodies. The results suggest that the linker region between segment S5 and S6 of domain IV is involved in benzothiazepine binding. This site is different from the dihydropyridine and verapamil binding sites.
Systematic substitution of individual bases in two important single‐stranded regions of the HDV ribozyme for evaluation of the role of specific bases
Authors: Suh Young-Ah , Kumar P.K.R. , Kawakami Junji , Nishikawa Fumiko , Taira Kazunari , Nishikawa Satoshi
Published: July 2002

To elucidate the role of specific bases in the self‐cleavage activity of the human hepatitis delta virus (HDV) ribozyme, systematic substitutions of individual bases in two important single‐stranded regions [between nucleotides 726–731 (SSrA region) and 762–766 (SSrB region)] were carried out by oligonucleotide‐directed point mutagenesis. Among the mutants obtained, 12 mutants (G726 variants, G727A, G727C, G728C, G762A, G762C, C763 variants and A766C) could not tolerate the respective base‐substitutions and self‐cleavage activities were reduced to very low levels (10%), suggesting a requirement of the respective bases. In particular, G726 in the SSrA region and C763 in the SSrB region were found to be essential for the ribozyme activity. We could determine the preferred sequences, 5′‐G‐G‐(G/A/U)‐N‐(A/U/G)‐Pu‐3′for SSrA and 5′‐(G/U)‐C‐N‐(A/G/U)‐A‐3′ for SSrB regions, respectively.
A homology‐based molecular model of the proline‐rich homeodomain protein Prh, from haematopoietic cells
Authors: Neidle Stephen , Goodwin Graham H.
Published: July 2002

A molecular structural model for the homeodomain of the haematopoietic protein Prh together with its DNA recognition sequence, has been built using the known crystal structure of the MATα2 homeodomain as a starting‐point. The modelling procedure used main and side‐chain optimisations by means of molecular mechanics/simulated annealing procedures to obtain stereochemically plausible geometries. The resulting structure has a number of specific interactions in both major and minor grooves of the DNA that serve to define the consensus binding sequence for Prh. In particular, the side‐chain of glutamine 50 is postulated to be involved in hydrogen bonds to adjacent adenine and cytosine bases within the consensus sequence.
Selective inhibition of lignoceroyl‐CoA synthetase by adenosine 5′‐alkylphosphates
Authors: Shiraishi Takayuki , Tezuka Kazuko , Uda Yutaka
Published: July 2002

Structural analogs of adenosine 5′‐acylphosphates, which are intermediates of the reaction catalysed by acyl‐CoA synthetases, were synthesized by condensing primary alcohols with AMP to examine the inhibitory effects on the lignoceroyl‐CoA and palmitoyl‐CoA synthetase activities. Hexadecyl, octadecyl, eicosyl, docosyl and tetracosyl esters of AMP were remarkably potent inhibitors of the lignoceroyl‐CoA formation. On the other hand, the eicosyl, docosyl or tetracosyl esters of AMP did not behave as significant inhibitors of the palmitoyl‐CoA formation at the concentration at which the two other shorter chain analogs were effective. Namely, these longer alkyl esters of AMP have selective inhibitory effects on the lignoceroyl‐CoA synthetase activity. The K
i value of adenosine 5′‐tetracosylphosphate, the most potent inhibitor, was about one tenth lower than the K
m value for the substrate lignoceric acid. Furthermore, the results support the notion that lignoceroyl‐CoA synthetase is distinct from palmitoyl‐CoA synthetase.
Molecular cloning of a novel mouse aspartic protease‐like protein that is expressed abundantly in the kidney
Authors: Mori Kiyoshi , Ogawa Yoshihiro , Tamura Naohisa , Ebihara Ken , Aoki Tomohiro , Muro Seiji , Ozaki Shoichi , Tanaka Issei , Tashiro Kei , Nakao Kazuwa
Published: July 2002

By use of the signal sequence trap method, we isolated a cDNA encoding a novel aspartic protease‐like protein from the mouse kidney, and termed it ‘kidney‐derived aspartic protease‐like protein (KAP).’ The protein, a 419‐amino‐acid polypeptide with a 16‐amino‐acid signal sequence, had 47% identity with mouse cathepsin D, and its overall structure was closely related to known aspartic proteases. Northern blot analysis revealed that KAP mRNA is expressed at the highest level in the kidney, at a moderate level in the lung, and at low levels in the spleen and adipose tissue. In situ hybridization analysis demonstrated that the mRNA is expressed abundantly in the proximal straight tubule and slightly, but significantly, in the proximal convoluted tubule in the kidney. This intra‐renal distribution differs distinctly from those of previously reported proteases such as cathepsins B, D, and H.
Identification of a specific amino acid cluster in the calmodulin‐binding domain of the neuronal nitric oxide synthase
Authors: Watanabe Yasuo , Hu Yu , Hidaka Hiroyoshi
Published: July 2002

© 1997 Federation of European Biochemical Societes.
Glycosylation at Asn‐289 facilitates the ligand‐induced conformational changes of human Glu‐plasminogen
Authors: Mølgaard Lone , Ponting Chris P , Christensen Ulla
Published: July 2002

Glu‐plasminogen exists in two major glycoforms (I and II). Glycoform I contains carbohydrate chains linked to Asn‐289 and Thr‐346, whereas glycoform II is glycosylated only at Thr‐346. Disparities in carbohydrate content lead to differences in the important functional properties of the zymogen, e.g. the kinetics of activation. The kinetics of the large ligand‐induced conformational changes of each of the Glu‐plasminogen glycoforms have been studied using stopped‐flow fluorescence. The results are in accordance with a conformational change governed by positive co‐operative binding at two weak lysine‐binding sites. Additional glycosylation at Asn‐289 in Glu‐plasminogen I results in a two‐fold increase in the overall dissociation constant of a ligand, trans‐4‐aminomethyl‐cyclohexane carboxylic acid. This effect stems directly from the reaction step during which the conformational changes occur. This implies a higher population of Glu‐plasminogen I in the open conformation even in the absence of ligands, and thus accounts for a higher rate of activation of Glu‐plasminogen I, in comparison with Glu‐plasminogen II.
Resistance to nitrophenolic herbicides and metronidazole in the cyanobacterium Synechocystis sp. PCC 6803 as a result of the inactivation of a nitroreductase‐like protein encoded by drgA gene
Authors: Elanskaya Irina V , Chesnavichene Egle A , Vernotte Claudie , Astier Chantal
Published: July 2002

Dinoseb is a herbicide known to inhibit photosystem II electron transfer like DCMU, triazine and phenolic‐type herbicides. The mutant Din7 of the cyanobacterium Synechocystis sp. PCC 6803, selected for resistance to dinoseb, and the mutant Ins2, constructed by the insertion of the kanamycin resistance cassette into the drgA gene, were cross‐resistant to other nitrophenolic herbicides (DNOC, 2,4‐dinitrophenol) and to the cell inhibitor metronidazole but not to the photosystem II inhibitors DCMU or ioxynil. The Din7 mutant had the same characteristics of photosystem II inhibition by dinoseb as the wild type. This result suggested the existence of another site for dinoseb inhibition. The wild type cells modified dinoseb to a non‐toxic product that gave an absorption spectrum similar to that of dithionite treated dinoseb containing reduced nitro groups. In contrast, the Din7 mutant did not modify dinoseb. These phenomena were controlled by the drgA gene encoding a protein which showed similarity to several enzymes having nitroreductase activity. The addition of superoxide dismutase to the medium relieved the toxic effect of dinoseb in wild type cells but not in Din7. It is proposed that in wild type cells of Synechocystis sp. PCC 6803 the DrgA protein is involved in detoxification of dinoseb via the reduction of the nitro group(s) and this process is accompanied by the formation of toxic superoxide anions. Mutations blocking the activity of the DrgA protein lead to the development of resistance to nitrophenolic herbicides and metronidazole.