bluuebunny/crossref_metadata_2025 huggingface dataset:
Speed change and traffic safety power model for inter-urban roads with heterogeneous traffic
Authors: Siregar Martha , Tjahjono Tri , Nahry N
Published: June 2021

The aim of this study is to develop the power model of the relationship between speed and traffic safety. As the inter-urban roads are characterised with heterogeneous traffic, the heterogeneity became the focus of the analysis. The present study analysed the effects of various types of vehicles through a number of speed change combinations and developed six equations: number of fatal accidents, number of fatalities, number of fatal and serious injury accidents, number of fatal or serious injuries, number of injury accidents and number of injured road users. The results indicated that the Power Model showed high predictability of the speed-accident relationship. The models fit the data well with Rsq in the range of 0.6-0.8. The vehicle category-specific ratio power models exhibited how traffic heterogeneity accounts for traffic safety. The equations' power varies with the types of vehicles, indicating the different sensitivity of accidents and casualties to the speed ratios. Overall, with the power estimates around one, except for all injured victims, the estimates were systematically smaller than those that were initially inferred in Nilsson's Power model. The values indicated that the increase in speed determined the increase in the number of accidents and casualties from year to year. The present study successfully developed the first speed-traffic safety Power Model for Indonesia. As it is exclusively dependent on the speed changes, the model can well describe the direction of change in traffic safety irrespective of other changes in the driving environment factors.
The Power of Interviewing Students
Authors: MacVicar Theresa J. , Brodesky Amy R. , Fagan Emily R.
Published: June 2021

A teacher uses formative assessment interviews to uncover evidence of students’ understandings and to plan targeted instruction in a mathematics intervention class. We present an example of a student interview, a discussion of the benefits and challenges of conducting interviews, and actionable suggestions for implementing them.
Hidden in Plain Sight
Authors: Aminata Dionne , Peart Deborah , Turner Kaneka
Published: June 2021

Dionne Aminata, Deborah Peart, and Kaneka Turner created #Blackwomenrockmath to connect and uplift Black women in mathematics education after recognizing the need for greater representation and support.
Taking a Cue from Conic Sections
Authors: Jacob Guidry
Published: June 2021

First graders learn about artist Wayne Thiebaud and explore estimation, counting, and probability while creating an artistic masterpiece.
Partial Pies
Authors: Marshall Jennifer
Published: June 2021

A series of tasks encourage students to reflect on the reasonableness of their number sense and use benchmarks to refine their estimations.
IMPLEMENTATION OF THE FIRST QFD MATRIX IN A FIXING DEVICE FOR WEAR MASKS
Authors: BENITEZ LOZANO ADRIAN JOSE , GIRALDO HERNANDEZ MILDRED JULIANA
Published: June 2021

ABSTRACT:
This paper presents the implementation of the first matrix known as house of quality (HOQ) in the framework of ´quality function deployment´ (QFD) methodology in a fixing device for wear masks. As a starting point, the customer´s voice is interpreted through the Kano model, which achieves the unique classification of customer requirements and technical aspects, in response to this by the manufacturer, are essential inputs to build the HOQ. In this house, the importance level scale of the requirements is shown, the correlation between them and the technical aspects, in order to achieve right decisions-making. Subsequently, the initial device design is presented, where the objectives that are expected to be obtained and its functionality are specified. For this, a commercial software in computer aided design (CAD) was used. An initial device prototype was obtained, with additive manufacturing technology or 3D printing by fused deposition melting. With the previously mentioned results, close scenarios would be achieved for the device´s final design, his validation and the scale production viability.

Key Words: Quality Function Deployment (QFD), KANO Model, House Of Quality (HOQ), Design Methodology.
Pour une vision géopolitique de l’identification des risques dans les mégaprojets : le cas de la centrale nucléaire de Jaitapur en Inde
Authors: Belhoste Nathalie
Published: June 2021

Cet article s’intéresse à la façon dont le raisonnement géopolitique peut enrichir l’étude de l’analyse du contexte des entreprises participant aux mégaprojets dans une perspective d’identification des risques. En détaillant cette méthode d’analyse particulière et au travers de l’analyse du cas de la centrale nucléaire de Jaitapur en Inde, il met en avant l’intérêt de détailler les chaînes relationnelles entre les risques eux-mêmes en raisonnant en termes de territoire, de représentation, de création de déséquilibre ou de rupture d’équilibre grâce à une observation multiscalaire et multi disciplinaire. Il appelle au développement d’une géopolitique des mégaprojets afin de minimiser les risques d’investissement.
Estudio y análisis de la evolución de los estudiantes matriculados en titulaciones de Educación Musical en la Universidad Autónoma de Madrid
Authors: Cuenca Rodríguez María Elena , Pérez-Eizaguirre Miren , Morales Fernández Ángela
Published: June 2021

Este artículo muestra una investigación descriptiva y analítica de datos institucionales a lo largo del tiempo. Los objetivos planteados se circunscriben a la descripción de la evolución de la antigua especialidad de Música en la Facultad de Formación de Profesorado de la Universidad Autónoma de Madrid, así como a los factores determinantes de esta evolución en la pérdida tanto cualitativa, desde el punto de vista curricular, como cuantitativa en lo que respecta al cómputo en créditos/horas con la aparición de las menciones. Por otra parte, se referencia el lugar que ocupa la Mención de Educación Musical en el conjunto de menciones de la citada Facultad, tanto para el Grado de Maestro de Primaria como de Infantil. Los resultados evidencian de forma definida el concepto de maestro especialista frente al de maestro generalista en la evolución legislativa. Por otra parte, la conclusión más notable es que, con las nuevas menciones, la Educación Musical, ha perdido de forma relevante un espacio formativo para la Educación Musical en la Educación Infantil y Primaria, considerando las cifras de estudiantes de nuevo ingreso y comparándolas con las de la antigua Diplomatura de la Especialidad de Música y las de las demás menciones ofertadas actualmente.
Sustainability Indicators in Heating Systems Towards Climate Neutrality
Authors:   , Prodaņuks Toms
Published: June 2021

The European Union has declared the goal of achieving climate neutrality by 2050, ensuring economy with zero net greenhouse gas (GHG) emissions. To achieve this goal, the EU has announced the European Green Deal which includes an action plan to accelerate efficient resource usage while moving towards circular economy as well as to restore biodiversity and reduce pollution. The transition to climate neutrality is urgent and offers an opportunity to build a better future. In order to achieve climate neutrality, society and all economic sectors must play their part. Increasing the efficiency of heat production and reducing consumption is considered one of the key tools for achieving the EU’s climate and energy goals by 2030, which envisage at least a 40 % reduction in GHG emissions, using 1990 as a baseline, at least a 32 % share of renewable energy and a 32.5 % increase in energy efficiency. In accordance with the EU climate and energy policy, the Latvia’s National Energy and Climate Plan 2021–2030 has been developed, and it includes national objectives and main actions that are directly or indirectly related to the increase of the efficiency in heat energy production and the reduction of consumption focusing on renewable energy. The overall aim of the present Doctoral Thesis is to evaluate heating systems in Latvia using sustainability indicators, including heat energy producers and end-users, make proposals on potential methodologies to increase the efficiency of the heating system and to reduce GHG emissions, emphasizing the use of renewable energy sources. An evaluation of various technologies and methods has been developed, which offers complex solutions for increasing the energy efficiency of heat energy producers.
On the development of the concept of neighborliness in the Russian housing Law
Authors: Kirakosyan Susana Arsenovna , Odnachev Pavel Sergeevich
Published: June 2021

The subject of this research is the relevant although poorly studied issued of neighborly relations in the Russian housing law. The authors set the goal to analyze the current legal regulation of neighborly relations in the housing sector, and substantiate the need for the development of the concept of neighborliness in the Russian housing law and legislation. Such concept aims to form the culture of living in a multifamily residential building, overcome excessive individualism that cultivates complete disunity of interests and indifference of neighbors to each other and to the fate of common property.  The authors explore the problem of neighborly relations in the housing sector, viewing neighborship from two perspectives: as a social institution of the neighborhood community and as a behavioral standard of particular subjects – neighbors. The need for the development of the concept of neighborliness is substantiated. This fully corresponds to the historical path of development of neighborly relations in the housing sector and the objective pursued by the legislator –increase the responsibility and awareness of the housing owners. The concept of neighborliness is a product of the development of the doctrine and law enforcement practice in the sphere of neighborly relations, and should become a part of the new housing policy of the Russian Federation. The concept of neighborliness includes such elements, as objective, principles, functions, and boundaries of neighborliness.
La gramática de construcciones. Una mirada externa
Authors: Bosque Ignacio
Published: June 2021

En este artículo se analiza la Gramática de Construcciones como marco teórico, así como algunas de sus conexiones con otros enfoques, sean antiguos o modernos. El objetivo del trabajo no es oponerse a este modelo en su conjunto o defender una teoría alternativa a él, sino valorar sus aspectos positivos y destacar a la vez aquellos que no lo son tanto, examinados por un lingüista no constructivista. Entre los aciertos de ese marco teórico se resalta especialmente la concepción escalar o gradual de la composicionalidad, con notables consecuencias para la relación léxico-sintaxis. Entre los aspectos menos positivos se menciona la atribución de significado a las construcciones mismas, así como las dificultades que el modelo presenta para incorporar las relaciones sintácticas que se establecen a distancia.
La gramática de construcciones. Una mirada interna, periférica y aplicada
Authors: Gras Pedro
Published: June 2021

Este artículo constituye una respuesta a la crítica de la gramática de construcciones realizada por Ignacio Bosque en su trabajo La gramática de construcciones: una mirada externa. La crítica de Bosque se complementa con una mirada interna, periférica y aplicada. Para contextualizar mi respuesta, comienzo presentando una panorámica de los enfoques constructivistas, para poner de relieve la existencia de diferencias en cuanto a los intereses como a las herramientas conceptuales y el grado de formalización, así como los aspectos más destacados de los enfoques constructivistas para mis tareas como analista de la sintaxis coloquial (periferia de la sintaxis) y profesor de español como lengua extranjera (visión aplicada). En la segunda parte del texto, respondo a las principales críticas de Bosque desde la versión de la gramática de construcciones desarrollada por Charles Fillmore, que debe dar cuenta tanto de las expresiones idiomáticas como de las composicionales. El objetivo final del texto es contribuir al dialogo interteórico mostrando que las diferencias entre constructivistas y proyeccionistas no son tan extremas como a veces se suele asumir.
Seafloor Pipeline Detection With Deep Learning
Authors: Schøyen Vemund Sigmundson , Warakagoda Narada Dilp , Midtgaard Øivind
Published: June 2021

This paper presents fast, accurate, and automatic methods for detecting seafloor pipelines in multibeam echo sounder data with deep learning. The proposed methods take inspiration from the highly successful ResNet and YOLO deep learning models and tailor them to the idiosyncrasies of the seafloor pipeline detection task.

We use the area between lines and Hausdorff line distance functions to accurately evaluate how well methods can localize (pipe)lines. The same functions also show promise as loss functions compared to standard mean squared error, which does not include the regression variables' geometrical interpretation.

The model outperforms the highest likelihood baseline by more than 35% on a region-wise F1-score classification evaluation while being more than eight times more accurate than the baseline in locating pipelines. It is efficient, operating at over eighteen 32-ping image segments per second, which is far beyond real-time requirements.
Comparative sequence and structure of circular RNAs from two isolates of lucerne transient streak virus
Authors: Keese Paul , Bruening George , Symons Robert H.
Published: July 2002

The sequences of the circular viroid‐like RNA 2 (virusoid) from two isolates of lucerne transient streak virus (LTSV) have been determined. They both contain 324 residues and share 98% sequence homology. The proposed secondary structures fit a highly base‐paired rod‐like model as shown previously for viroids and two other virusoids, velvet tobacco mottle virus (VTMoV) and Solanum nodiflorum mottle virus (SNMV). Except for one region of sequence and positional homology (GAUUUU, residues 21–26) LTSV virusoid exhibits limited homology with all presently known virusoids, including those from VTMoV, SNMV and subterranean clover mottle virus.
Interaction of colchicine analogues with purified tubulin
Authors: Choudhury Goutam Ghosh , Banerjee Ashok , Bhattacharyya Bhabatarak , Biswas Birendra B.
Published: July 2002

Binding of two colchicine analogues, desacetamidocolchicine and 2‐methoxy‐5‐(2′,3′,4′‐trimethoxyphenyl) tropone to purified tubulin have been studied. Both analogues bind to tubulin with a significant increase in fluorescence polarization of the drugs in solutions containing tubulin. The K
d for tubulin‐drug complexes were found to be 1.25 × 10−6 M and 1.08 × 10−6 M for desacetamidocolchicine and 2‐methoxy‐5‐(2′,3′,4′‐trimethoxyphenyl) tropone, respectively. Scatchard analysis of the fluorescence titration curve of drug tubulin interaction also gives the values of stoichiometry and affinity constant. These were 0.8 and 1.6 × 106 M−1 for desacetamidocolchicine, and 0.9 and 0.58 × 106 M−1 for 2‐methoxy‐5‐(2′,3′,4′‐trimethoxyphenyl) tropone.
Structural organization of C‐terminal parts of fibrinogen Aα‐chains
Authors: Medved' L.V. , Gorkun O.V. , Privalov P.L.
Published: July 2002

Calorimetric studies of fibrinogen melting and of its early degradation products have shown that the C‐terminal parts of both the Aα‐chains form structural domains which strongly interact with each other in the native fibrinogen molecule.
Complete amino acid sequence of glucose dehydrogenase from Bacillus megaterium
Authors: Jany Klaus-Dieter , Ulmer Wolfgang , Fröschle Marion , Pfleiderer Gerhard
Published: July 2002

The amino acid sequence of glucose dehydrogenase from Bacillus megaterium has been determined. The enzyme consists of 4 identical subunits, each containing 262 amino acid residues. Its structure was established using manual Edman degradation procedures after modification of the enzyme in the native form with reagents specific to the amino acids histidine, tyrosine, tryptophan and lysine in order to identify residues involved in catalysis or located in the subunit binding area.
Relationships of respiratory chain and ATP‐synthetase in energized mitochondria
Authors: Krasinskaya Inna P. , Marshansky Vladimir N. , Dragunova Svetlana F. , Yaguzhinsky Lev S.
Published: July 2002

The present study reveals that the previously described effect of ATP‐synthetase inhibition concomitant with inhibition of respiratory chain functioning may be observed at different absolute values of Δψ on the mitochondrial membrane. This fact points out that the membrane potential is not a unique regulator in coupling of ATP‐synthetase and respiratory chain activities. We found, using the double‐inhibitor titration technique, that ATP‐synthetase inhibition induces proportional inhibition of respiratory chain enzymes and vice versa respiratory chain inhibition induces proportional inhibition of ATP‐synthetase. This effect is shown to exist only when osmolarity is close to 150–300 (mosM) (in the physiological range). The coupling effectivity (ADP/O) of mitochondria under these conditions is maximal. Under conditions of high osmolarity (400–600 mosM) the respiratory chain and ATP‐synthetase behave as if they were coupled by bulk phase Δ{ovbar|μ|}H+
, from the kinetic point of view.
A unique photosynthetic reaction center from Heliobacterium chlorum
Authors: Fuller R.Clinton , Sprague Sallie G. , Gest Howard , Blankenship Robert E.
Published: July 2002

A previously unknown type of photosynthetic reaction center in the brownish‐green bacterium Heliobacterium chlorum is described. The reaction center is tightly bound in a highly proteinaceous undifferentiated plasma membrane and contains bacteriochlorophyll g, which has major in vivo absorbancies at 788, 576 and 370 nm. The purified membrane shows a reversible photobleaching at 798 nm; the reaction center bacteriochlorophyll g is designated P798. A reversible photobleaching at 553 nm is assigned to photooxidation of a membrane‐bound c‐type cytochrome. The membrane structure, pigment composition and photochemical properties suggest that H. chlorum may represent a fifth family of anoxygenic photosynthetic procaryotes.
Impaired α‐carboxyamidation of gastrin in vitamin C‐deficient guinea pigs
Authors: Hilsted Linda , Rehfeld Jens F. , Schwartz Thue W.
Published: July 2002

The biosynthetic activation of many hormonal peptides requires enzymatic a‐carboxyamidation via glycine‐extended intermediate forms. By specific radioimmunochemical measurement on extracts of guinea pig antra, we found that vitamin C deficiency induced a 30‐fold increase in glycine‐extended (i.e. inactive) gastrins. The results indicate that ascorbic acid is neccessary for α‐carboxyamidation in vivo, and thus, that the biosynthetic activation of hormonal peptides can be modified by simple dietary means.
Glycosylation of bacterial cellulases prevents proteolytic cleavage between functional domains
Authors: Langsford M.L. , Gilkes N.R. , Singh B. , Moser B. , Miller R.C. , Warren R.A.J. , Kilburn D.G.
Published: July 2002

Glycosylated cellulases from Cellulomonas fimi were compared with their non‐glycosylated counterparts synthesized in Escherichia coli from recombinant DNA. Glycosylation of the enzymes does not significantly affect their kinetic properties, or their stabilities towards heat and pH. However, the glycosylated enzymes are protected from attack by a C. fimi protease when bound to cellulose, while the non‐glycosylated enzymes yield active, truncated products with greatly reduced affinity for cellulose.
Cloning and high‐level expression of a chloroperoxidase gene from Pseudomonas pyrrocinia in Escherichia coli
Authors: Wolfframm Christina , van Pée Karl-Heinz , Lingens Franz
Published: July 2002

A chloroperoxidase gene from Pseudomonas pyrrocinia was cloned into Escherichia coli using the cosmid vector pJB8. The gene coding for the chloroperoxidase could be localized to a 1.5 kb fragment of DNA which was subcloned into the high‐copy‐number plasmid pUC18. In one subclone increased halogenating activity could be found which was 570‐fold greater than in P. pyrrocinia. The halogenating enzyme was identified as the chloroperoxidase by SDS‐polyacrylamide gel electrophoresis.
Modulation of protein kinase C activity by NaF in bone marrow derived macrophages
Authors: Hauschildt S. , Hirt W. , Bessler W.
Published: July 2002

Stimulation of murine bone marrow derived macrophages with NaF, prelabeled with [1‐14C]oleate and [3H]inositol, increased the production of inositol phosphates and the release of 1,2‐[14C]diacylglycerol (DAG). Moreover, NaF also induced activation of protein kinase C. These results indicate that bone marrow derived macrophages exhibit a phosphatidyl‐4,5‐bisphosphate phospholipase C activity, sensitive to NaF, which might be modulated by G‐proteins. Activation of protein kinase C could have been mediated by NaF‐induced release of DAG.
Primary structure of sheep prostaglandin endoperoxide synthase deduced from cDNA sequence
Authors: Yokoyama Chieko , Takai Toshiyuki , Tanabe Tadashi
Published: July 2002

The complete amino acid sequence of prostaglandin endoperoxide synthase from sheep vesicular gland has been deduced by cloning and sequence analysis of DNA complementary to its messenger RNA. The results were confirmed by digestion of the enzyme with carboxypeptidase Y and by automated Edman degradation of the intact enzyme polypeptide and peptide fragments obtained by limited proteolysis of the enzyme with Achromobacter proteinase I. Mature sheep prostaglandin endoperoxide synthase is shown to be composed of 576 amino acids with an M
r of 66 175. The precursor peptide is predicted to contain a 24‐residue signal peptide. The serine residue susceptible to acetylation by aspirin is found to be located near the C‐terminus of the enzyme polypeptide.
Formation and release of nitric oxide from human neutrophils and HL‐60 cells induced by a chemotactic peptide, platelet activating factor and leukotriene B4
Authors: Schmidt Harald H.H.W. , Seifert Roland , Böhme Eycke
Published: July 2002

Vascular endothelial cells and neutrophils synthesize and release potent vasodilatatory factors, i.e. endothelium‐derived relaxing factors (EDRF) and neutrophil‐derived relaxing factors (NDRF). One EDRF has been identified as nitric oxide (NO) derived from arginine. We studied the synthesis and release of NO from human neutrophils stimulated with the chemotactic peptide N‐formyl‐L‐methionyl‐L‐leucyl‐L‐phenylalanine, platelet activating factor or leukotriene B4. The formation and release of NO was enhanced several‐fold in the presence of superoxide dismutase, probably by inhibiting superoxide‐induced breakdown of NO. The formation and release of NO but not the formation of superoxide anions was decreased in neutrophils pretreated with L‐canavanine, an inhibitor of arginine‐utilizing enzymes. Our data suggest that at least one NDRF is identical with NO or another labile NO containing compound derived from arginine.
Biphasic increase in intracellular calcium induced by platelet‐activating factor in macrophages
Authors: Randriamampita C. , Trautmann A.
Published: July 2002

In single mouse macrophages stimulated by platelet‐activating factor (PAF), the intracellular calcium concentration (Cai) monitored with fura‐2 at room temperature presents a biphasic increase, including a transient and a more sustained component. After pulse administration of PAF, the first phase lasts for a few seconds and reaches a peak value of 0.5–1 μM Ca2+ at high PAF concentration. The amplitude of this peak is independent of extracellular Ca+ concentration, suggesting that the initial Ca2+ transient is due to the release of Ca2+ from intracellular stores. The second phase of the response lasts for several minutes; its maximum amplitude is reached 1–2 min after the brief initial PAF stimulation. This phase, suppressed in zero external Ca2+ and increased in 10 mM Ca2+, is probably due to influx of Ca2+ through the plasma membrane. This secondary Ca2+ increase is blocked by 10–50 μM lanthanum. At low PAF concentration, the initial Ca2+ transient is not followed by a second phase, showing that the initial rises of Ca2+ and of its activator (presumably inositol trisphosphate) are not sufficient to trigger the second phase of Ca2+ increase.
Glucose‐induced synthesis of diacylglycerol de novo is associated with translocation (activation) of protein kinase C in rat adipocytes
Authors: Ishizuka Tatsuo , Hoffman Joanne , Cooper Denise R. , Watson James E. , Pushkin David B. , Farese Robert V.
Published: July 2002

Addition of glucose (5–20 mM) to rat adipocytes provoked dose‐related increases in diacylglycerol, without increasing production of [3H]inositol phosphates. Cytosolic protein kinase C enzyme activity and immunoreactivity decreased within 1–5 min of 5 mM glucose addition, and further over 20 min. Membrane protein kinase C increased stoichiometrically during the first 5 min and then decreased. Higher concentrations (10 and 20 mM) of glucose provoked greater and more rapid decreases of cytosolic and membrane protein kinase C. Our findings suggest that glucose stimulates diacylglycerol production by providing substrate for phosphatidic acid synthesis de novo, and this is associated with translocative activation of protein kinase C.
The structure of syringomycins A1, E and G
Authors: Segre A. , Bachmann R.C. , Ballio A. , Bossa F. , Grgurina I. , Iacobellis N.S. , Marino G. , Pucci P. , Simmaco M. , Takemoto J.Y.
Published: July 2002

By a combination of 1D and 2D 1H‐ and 13C‐NMR, FAB‐MS, and chemical and enzymatic reactions carried out at the milligram level, it has been demonstrated that syringomycin E, the major phytotoxic antibiotic produced by Pseudomonas syringae pv. syringae, is a new lipodepsipeptide. Its amino acid sequence is Ser‐Ser‐Dab‐Dab‐Arg‐Phe‐Dhb‐4(Cl)Thr‐3(OH)Asp with the β‐carboxy group of the C‐terminal residue closing a macrocyclic ring on the OH group of the N‐terminal Ser, which in turn is N‐acylated by 3‐hydroxydodecanoic acid. Syringomycins A1 and G, two other metabolites of the same bacterium, differ from syringomycin E only in their fatty acid moieties corresponding, respectively, to 3‐hydroxydecanoic and 3‐hydroxytetradecanoic acid.
Effects of benzyl alcohol on transferrin and low density lipoprotein receptor mediated endocytosis in leukemic guinea pig B lymphocytes
Authors: Sainte-Marie J. , Vignes M. , Vidal M. , Philippot J.R. , Bienvenüe A.
Published: July 2002

We demonstrated that benzyl alcohol, a neutral local anesthetic drug, inhibits the uptake and degradation of lowdensity lipoprotein and endocytosis of transferrin receptors of guinea pig leukemic B lymphocytes (L2C). This inhibition is very rapid, concentration dependant and reversible by simple washing. Membrane fluidity of the living cells is also modified.
The β‐subunit of the gastric H+/K+‐ATPase can occur without the α‐subunit
Authors: Baldwin G.S.
Published: July 2002

The renal Na+/K+‐ATPase and the gastric H+/K+‐ATPase both contain α‐ and β‐subunits. We report here the identification and partial purification of a second population of the β‐subunit of the gastric H+/K+‐ATPase, which has no accompanying a‐subunit detectable by Coomassie blue staining or by Western blotting with monoclonal antibodies specific for the α‐subunit.
Carboxyatractylate‐sensitive uncoupling in liver mitochondria from ground squirrels during hibernation and arousal
Authors: Brustovetsky N.N. , Amerkanov Z.G. , Yegorova M.E. , Mokhova E.N. , Skulachev V.P.
Published: July 2002

Energy coupling parameters of liver mitochondria from hibernating and arousing ground squirrels have been studied. In the oligomycin‐treated mitochondria, carboxyatractylate, an inhibitor of the ATP/ADP‐antiporter, is shown to decrease the respiration rate, to increase the membrane potential and to lower the rate of the membrane‐potential discharge after the addition of cyanide to liver mitochondria from hibernating and arousing animals. BSA effectively substitutes for carboxyactactylate so that carboxyactactylate, added after BSA, has no effect. In mitochondria from hibernating animals, the maximal respiration rate in the presence of DNP and the rate of the membrane potential discharge in its absence are much lower than in those from arousing animals. It has been concluded that upon arousal of the animals from hibernation, the uncouling of oxidative phosphorylation, mediated by free fatty acids and ATP/ADP‐antiporter, parallels the respiratory chain activation.
The three carboxy‐terminal amino acids of human interleukin‐6 are essential for its biological activity
Authors: Krüttgen Alex , Rose-John Stefan , Dufhues Gabi , Bender Sven , Lütticken Claudia , Freyer Peter , Heinrich Peter C.
Published: July 2002

We have constructed on the cDNA level deletion mutants of human interleukin‐6 lacking one, two, three or four amino acids from the carboxyterminus of the molecule. After in vitro transcription and translation the biological activity of these deletion mutants was determined by two independent bioassays. Both, the mouse B9 cell proliferation assay and the fibrinogen induction assay with the human hepatoma cell line HepG2 led to the following result: already the removal of the last amino acid resulted in a five‐fold loss of biological activity. An additional slight reduction was seen when two amino acids were removed from the carboxy‐terminus. Interleukin‐6 lacking three or four C‐terminal amino acids were completely inactive. The presented results emphasize the extreme importance of the carboxy‐terminus of interleukin‐6 for its biological function.
Chloroquine inhibition of cholera toxin
Authors: Liang Yi-fan , Peterson Johnny W. , Jackson Christopher A. , Reitmeyer James C.
Published: July 2002

Cholera toxin (CT) stimulated adenylate cyclase and a phospholipase which elevated levels of 3.5‐cyclic adenosine monophosphate (cAMP) and arachidonic acid (AA). The AA was quickly converted to prostaglandins (PGs) via the cyclo‐oxygenase pathway. Chloroquine exerted minimal inhibition of cAMP levels in CT‐treated cells, although CT‐induced release of [3H]AA and PGs was blocked completely when the drug was added in concentrations as low as 0.1 mM (30 μγ ml). Inhibition of [3H]AA release was complete when chloroquine was added before or within 30 min after CT. The capacity of chloroquine to inhibit either phospholipase C (PLC) or phospholipase A2 (PLA2) could explain the antisecretory activity of this drug.
Bombesin receptor from Swiss 3T3 cells Affinity chromatography and reconstitution into phospholipid vesicles
Authors: Coffer Arnold , Sinnett-Smith James , Rozengurt Enrique
Published: July 2002

Bombesin and its mammalian counterpart gastrin releasing peptide (GRP) are potent mitogens for Swiss 3T3 cells in which distinct high affinity receptors have been identified. We developed here a probe for specific ligand affinity chromatography by coupling biotin to [lys1]bombesin. The resulting biotinylated [lys3]bombesin (BLB) retained biological activity as judged by inhibition of [125I]GRP binding to intact cells and membrane preparations and stimulation of rapid Ca2+ mobilization and DNA synthesis in intact cells. Using this ligand and magnetised beads coated with streptavidin, we extracted differentially a single protein from detergent‐solubilized Swiss 3T3 membranes in a BLB‐dependent manner. Visualization was achieved either after autoradiograph of metabolically labelled proteins with [13S]methionine or by silver staining of larger preparations. In other experiments, elution of BLB‐receptor complexes bound to streptavidin beads was carried out at neutral pH and eluted fraction was reconstituted into phospholipid vesicles. This procedure revealed[125I]GRP binding activity that exhibited saturability, specificity and a 1946‐fold increase in specific activity.
Proglycogen: A low‐molecular‐weight form of muscle glycogen
Authors: Lomako Joseph , Lomako Wieslawa M. , Whelan William J.
Published: July 2002

We recently reported that muscle contains a trichloroacetic acid‐precipitable component having M
r approx. 400 kDa that can be glucosylated by an endogenous enzyme acting on UDPglucose. This component contains within itself the autocatalytic, self glucosylating protein glycogenin, the primer for glycogen synthesis. We now report that this substance, to which we give the name proglycogen, is a glycogen‐like molecule constituting about 15% or total glycogen. It acts as a very efficient acceptor of glucose residues added from UDPglucose. Further, that the endogenous enzyme that adds the glucose to proglycogen is not the autocatalytic protein but a glycogen synthase‐like enzyme. Proglycogen may be an intermediate in the synthesis and degradation of macromolecular glycogen and may exist and be metabolized as a separate entity. Consideration should now be given to the revival of the concept that tissue contains two forms of glycogen. One is proglycogen. The other is the ‘classical’, macromolecular glycogen. Additionally, proglycogen and glycogen may be glucosylated by different forms of synthase.
Mutation in the sphingolipid activator protein 2 in a patient with a variant of Gaucher disease
Authors: Schnabel Doris , Schröder Maria , Sandhoff Konrad
Published: July 2002

The lysosomal degradation of glucosylceramide requires the hydrolase, glucosylceramide‐β‐glucosidase and a sphingolipid activator protein (Gaucher factor, SAP‐2, saposin C). Genetic defects in either of these lysosomal proteins cause phenotypically similar disorders in man, the Gaucher disease. SAP‐2 originates from a gene which generates a mRNA that codes for four homologous proteins. In a patient with an immunologically proven SAP‐2 deficiency a G1154 → T transversion (counted from A of the initiation codon ATG) was found in the mRNA of the SAP‐2 precursor which results in the substitution of Phe for Cys385 in the mature SAP‐2. The rest of the coding sequence remained entirely normal.
Syringopeptins, new phytotoxic lipodepsipeptides of Pseudomonas syringae pv. syringae
Authors: Ballio A. , Barra D. , Bossa F. , Collina A. , Grgurina I. , Marino G. , Moneti G. , Paci M. , Pucci P. , Segre A. , Simmaco M.
Published: July 2002

The primary structure of some new lipodepsipeptides named syringopeptins, produced by plant pathogenic strains of Pseudopmonas syringae pv. syringae has been determined by a combination of chemical methods, 1H and 13C NMR spectroscopy and FAB mass spectrometry. Two syringomycin‐producing strains afforded 3‐hydroxydecanoyl‐Dhb‐Pro‐Val‐Val‐Ala‐Ala‐Val‐Val‐Dhb‐Ala‐Val‐Ala‐Ala‐Dhb‐aThr‐Ser‐Ala‐Dhb‐Ala‐Dab‐Dab‐Tyr, with Tyr acylating a Thr to form a macrolactone ring, and smaller amounts of the 3‐hydroxydodecanoyl homologue. Evidence was obtained that a third syringomycin‐producing strain and a syringotoxin‐producing strain synthesize 3‐hydroxydecanoyl‐Dhb‐Pro‐Val‐Ala‐Ala‐Val‐Leu‐Ala‐Ala‐Dhb‐Val‐Dhb‐Ala‐Val‐Ala‐Ala‐Dhb‐aThr‐Ser‐Ala‐Val‐Ala‐Dab‐Dab‐Tyr, with Tyr and aThr forming again the macrolactone ring, and smaller amounts of the 3‐hydroxydodecanoyl homologue.
A unique vacuolar processing enzyme responsible for conversion of several proprotein precursors into the mature forms
Authors: Hara-Nishimura Ikuko , Inoue Kaori , Nishimura Mikio
Published: July 2002

Proprotein precursors of vacuolar components are transported from the endoplasmic reticulum into vacuoles, where they are proteolytically processed into their mature forms. However, the processing mechanism in plant vacuoles is very obscure. Characterization of a purified processing enzyme is required to determine whether a single enzyme is responsible for processing many vacuolar proteins with a large variability of molecular structure. If this is true, how can it recognize the numerous varieties of processing sites? We have now purified a processing enzyme (Mt
=37 000) from castor bean seeds. Our results show that the purified enzyme can process 3 different proproteins isolated from either the endoplasmic reticulum or transport vesicles in cotyledon cells to produce the mature forms of these proteins which are found at different suborganellar locations in the vacuole: the 2S protein found in the soluble matrix, the 11S globulin found in the insoluble crystalloid and the 51 kDa protein associated with the membrane. Thus a single vacuolar processing enzyme is capable of converting several proprotein precursors into their respective mature forms.
EPR spectroscopic characterization of an ‘iron only⌉ nitrogenase S = 3/2 spectrum of component 1 isolated from Rhodobacter capsulatus
Authors: Müller Achim , Schneider Klaus , Knüttel Karlheinz , Hagen Wilfred R.
Published: July 2002

The alternative nitrogenase of Rhodobacter capsulatus, isolated from a nifHDK deletion mutant, has been purified to near homogeneity and identified as an ‘iron only’ nitrogenase. The dithionite‐reduced component 1 (‘FeFe protein’) or this enzyme showed an EPR spectrum consisting of two components: a minor S = 12 signal at g = 1.93 and a very characteristic S = 32 signal of near‐stoichiometric intensity at g = 5.44. This resonance is very close to the highest possible g value (g = 5.46) for the coinciding two intradoublet subspectra of an S = 32 system or maximal rhombicity (E/D = 0.33)). The deviation from axial symmetry (increasing E/D) correlates with the stability, activity and substrate selectivity of the different (Mo, V, Fe) nitrogenases.
Ubiquitin metabolism in HeLa cells starved of amino acids
Authors: Hiroi Yuzo , Rechsteiner Martin
Published: July 2002

Radio‐iodinated ubiquitin (Ub) was introduced into HeLa cells by red blood cell‐mediated microinjection. The half‐life and solubility of Ub, as well as the molecular weight distributions of Ub conjugates, were then measured in HeLa cells grown in complete medium or in medium lacking amino acids and fetal calf serum. Ub metabolism was similar in the two sets of cells. Thus, the dramatic changes in Ub metabolism induced by thermal stress are not observed upon amino acid deprivation.
Expression of blood clotting Factor VIII:C gene in capillary endothelial cells
Authors: Banerjee Dipak K. , Tavárez José J. , Oliveira Caroline M.
Published: July 2002

The essential role of Factor VIII:C (FVIII:C, anti‐hemophilia factor A) as a cofactor for Factor IXa‐dependent activation of Factor X has been established. In this paper, we describe that capillary endothelial cells from bovine adrenal medulla express active FVIII:C gene. Accumulation of FVIII:C in conditioned media from an 8‐day‐old culture is approximately twice as high as that stored in the cell when immunoprecipitated FVIII:C was analyzed for its ability to convert Factor X to Factor Xa. Analysis of [35S]methionine‐labeled and immunoprecipitated FVIII:C from cells or conditioned media on SDS‐PAGE under fully denatured conditions indicated that the newly synthesized FVIII:C consists of heavy chain of M
r 200,000 and light chain of M
r 46,000. The secreted FVIII:C in the non‐reduced condition however, has a molecular weight of 270,000 which suggests that in native protein, the heavy and light chains are held together by S‐S bonds. Furthermore, susceptibility of the immunoprecipitated FVIII:C to N‐glycanase digestion establishes that the endothelial cells derived FVIII:C contains asparagine‐linked carbohydrate side chains.
CDP‐diacylglycerol synthesis in rat liver mitochondria
Authors: Mok Amy Y.P. , McDougall Gordon E. , McMurray William C.
Published: July 2002

CDP‐diacylglycerol for polyglycerophosphatide biogenesis can be synthesized within rat liver mitochondria. This membrane‐associated enzyme was predominantly located in the inner mitochondrial membrane. GTP had a significant effect in activating the microsomal CDP‐diacylglycerol synthase, especially if the microsomes were preincubated with GTP in the presence of phosphatidic acid. This stimulatory effect of GTP on the microsomal enzyme was not detected in the mitochondrial fractions. The enzymes could be solubilized from the membrane fractions using CHAPS, and the detergent‐soluble activity partially restored by addition of phospholipids. Mitochondrial and microsomal CDP‐diacylglycerol synthase activity could be completely separated by anion‐exchange column chromatography. The mitochondrial and microsomal CDP‐diacylglycerol synthases appear to be two distinct enzymes with different localization and regulatory characteristics.
Mapping and sequence‐specific identification of phosphopeptides in unfractionated protein digest mixtures by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry
Authors: Yip Tai-Tung , Hutchens T.William
Published: July 2002

We have demonstrated a procedure for the rapid (minutes), sensitive (<pmol), and sequence‐specific identification of phosphopeptides in unfractionated digests of phosphoproteins using matrix‐assisted UV laser desorption/ionization (MALDI) time‐of‐flight (TOF) mass spectrometry. The mass‐dependent identification of one specific 13‐residue phosphopeptide (S105‐K117), observed among the 153 possible trypsin digest fragments of human β‐casein (211 residues), was confirmed by amino acid sequence analysis of the ???P‐labeled peptide after isolation by reverse‐phase HPLC. MALDI‐TOF was also used to monitor the rate and extent to which an 18‐residue N‐terminal β‐casein peptide (R1‐K18) was phosphorylated in vitro. These results demonstrate that MALDI‐TOF may be used (i) to facilitate the identification of sequence‐specific sites of protein phosphorylation and dephosphorylation. (ii) to monitor protein and peptide phosphorylation and dephosphorylation reaction rate, even in complex unfractionated mixtures, (iii) to determine the minimum primary structure necessary for the phosphorylation of specific protein surface domains, and (iv) to evaluate the effects of intact protein phosphorylation and dephosphorylation on susceptibility to subsequent proteolytic events.
Characterization and regulation of the angiotensin II type‐1 receptor (binding and mRNA) in human adrenal fasciculata‐reticularis cells
Authors: Naville D. , Lebrethon M.C. , Kermabon A.Y. , Rouer E. , Benarous R. , Saez J.M.
Published: July 2002

The classical concept of human adrenal physiology indicates that only glomerulosa cells are the target of A‐II. Herein, we demonstrated that cultured human adrenal fasciculata‐reticularis cells were also responsive to this hormone. Indeed, these cells contained high affinity (K
d = 0.9–1.1 nM) and low capacity (8,000–13,000 sites/cell) A‐II receptors, and more than 95% of them were of the type‐1. These AT1 receptors are functional since A‐II was able to increase cortisol production after 48 h of treatment. These effects were inhibited by losartan, an ATI antagonist, but not by CGP 42112 A, an AT2 antagonist. The expression of the type‐1 A‐II recptor mRNA was detected in the whole adrenal in both adult and fetus, and in cultured human adrenal fasciculata‐reticularis cells. In these cells A‐II negatively regulated ATI receptor mRNA, and this effect was also mediated through the ATI receptor subtype.
Thioredoxin reduction dependent on α‐ketoacid oxidation by α‐ketoacid dehydrogenase complexes
Authors: Bunik Victoria , Follmann Hartmut
Published: July 2002

The pyruvate and α‐ketoglutarate dehydrogenase complexes isolated from pig heart mitochondria promote the reduction of thioredoxin in the presence of their α‐ketoacid substrates, coenzyme A, and free lipoate. Substrate‐specific generation of reduced thioredoxin was established by two independent methods, viz. reduction of insulin and thioredoxin reductase‐catalyzed NADPH formation. Dihydrolipoate accumulating in the absence of NAD+ is the likely intermediate. A redox function in α‐ketoacid oxidation provides a potential role for the specific thioredoxins previously identified by us in mitochondria.
Changes in the expression of guanine nucleotide‐binding proteins during differentiation of 3T3‐F442A cells in a hormonally defined medium
Authors: Kilgour Elaine , Anderson Neil G.
Published: July 2002

Using specific antisera, the expression of the G protein α subunits, G8, gi1, Gi2, Gi3, and G0, were determined in 3T3‐F442A cells during their differentiation to adipocytes in a hormonally defined medium. Differentiation caused distinct increases in the expression of two Gs isoforms and decreases in the expression of both Gi2 and Gi3. Differentiation also resulted in a 2‐ to 4‐fold increase in forskolin‐stimulated adenylyl cyclase activity and a 15‐fold increase in the response of cells to a β‐adrenergic agonist. The increase in Gs expression was also observed, to a lesser degree, in cells maintained at confluence under conditions where morphological conversion was negligible and the decreased expression of Gi2 and Gi3 and the increased β‐adrenergic responsiveness did not occur.
Mycalolide‐B, a novel and specific inhibitor of actomyosin ATPase isolated from marine sponge
Authors: Hori Masatoshi , Saito Shin-ya , Shin Yutaka Z. , Ozaki Hiroshi , Fusetani Nobuhiro , Karaki Hideaki
Published: July 2002

A toxin isolated from marine sponge, mycalolide‐B, inhibited smooth muscle contractions without changing cytosolic Ca2+ levels. It also inhibited Ca2+‐induced contraction in permeabilized smooth muscles. In native actomyosin prepared from chicken gizzard, mycalolide‐B inhibited superprecipitation and Mg2+‐ATPase activity stimulated by Ca2+ without changing myosin light chain phosphorylation. In the permeabilized muscle and native actomyosin preparation thiophosphorylated with ATPγS, mycalolide‐B inhibited ATP‐induced contraction and Mg2+‐ATPase activity, respectively, in the absence of Ca2+. Mycalolide‐B also inhibited Mg2+‐ATPase activity of skeletal muscle native actomyosin. Mycalolide‐B had no effect on calmodulin‐stimulated (Ca2+–Mg2+)‐ATPase activity of erythrocyte membranes. These results suggest that mycalolide‐B selectively inhibits actin—myosin interaction.
Structure of the nuclear encoded γ subunit of CF0CF1 of the diatom Odontella sinensis including its presequence
Authors: Pancic Peter G. , Strotmann Heinrich
Published: July 2002

Using a PCR‐product as homologous probe for screening of a cDNA library of the diatom Odontella sinensis overlapping cDNA clones were obtained which showed homologies to atpC‐genes of F0F1‐ATPases from different sources. Comparison of the deduced amino acid sequence with the N‐terminal sequence of the Odontella γ subunit obtained by protein sequencing, indicated that the complete 370 amino acid protein is processed to a mature protein of 315 amino acids. The 55 amino acids comprising the presequence consists of two segments, one resembling a signal sequence for cotranslational transport through ER membranes and one showing characteristics of a transit sequence for transport of proteins into chloroplasts of higher plants. This result is discussed with respect to the particular envelope structure of chromophytic plastids consisting of four membranes. The outer membrane contains ribosomes on its cytosolic surface. As in cyanobacterial γ subunits the regulatory sequence region, which is involved in thiol modulation of chloroplast ATPase of green algae and higher plants, is absent in the Odontella γ subunit.
Cloning and characterization of the entire cDNA encoded by ATP1AL1 — a member of the human Na,K/H,K‐ATPase gene family
Authors: Grishin Alexander V. , Sverdlov Vladimir E. , Kostina Mariya B. , Modyanov Nikolai N.
Published: July 2002

The cDNA for ATP1AL1 — the fifth member of the human Na,K‐/H,K‐ATPase gene family — was cloned and sequenced. The deduced primary ATP1AL1 translation product is 1,039 amino acids in length and has M
r of 114,543. The encoded protein has all of the structural features common to known catalytic subunits of P‐type membrane ion‐transporting ATPases and is equally distant (63–64% of identity from the Na,K‐ATPase isoforms and the gastric H,K‐ATPase. The ATP1ALI encoded protein was proposed to represent a new separate group within the family of human potassium‐dependent ion pumps.