bluuebunny/crossref_metadata_2025 huggingface dataset:
Implementing Rapid Durability Measure for Concrete Using Resistivity and Formation Factor
Authors: Weiss W. Jason , Qiao Chunyu , Isgor Burkan , Olek Jan
Published: November 2020

The durability of in-place concrete is a high priority issue for concrete pavements and bridges. Several studies have been conducted by INDOT to use electrical resistivity as a measure of fluid transport properties. Resistivity is dependent on the chemistry of the cement and supplementary cementitious system used, as such it has been recommended that rather than specifying resistivity it may be more general to specify the formation factor. Samples were tested to establish the current levels of performance for concrete pavements in the state of Indiana. Temperature and moisture corrections are presented and acceptable accelerated aging procedure is presented. A standardized testing procedure was developed (AASHTO TP 119–Option A) resulting in part from this study that provides specific sample conditioning approaches to address pore solution composition, moisture conditioning, and testing procedures. An accelerated aging procedure is discussed to obtain later age properties (91 days) after only 28 days.
FORMAÇÃO DE PROFESSORES E PROFISSÃO DOCENTE: O ESTADO DO CONHECIMENTO DA PESQUISA EM FORMAÇÃO NA REGIÃO DOS INCONFIDENTES - MG
Authors: Jardilino José Rubens Lima , Oliveri Andressa Maris Rezende , Sampaio Ana Maria Mendes
Published: November 2020

The educational field is inserted in a context of multiple actors, actions, and social implications, requiring the use of several viewpoints to understand its movement. As a result, this work aims to remember part of the training path and research trajectory of the Research Group -Teacher Education and Profession (FOPROFI), of the Graduate Program in Education of the Federal University of Ouro Preto. In order to do so, some of the research developed by the group that helps in the composition and knowledge of the field of teacher education, in the teaching occupation and in educational institutions will be treated. The researches were selected after the bibliographic survey of the works in the university repository. In addition, we sought to outline some considerations regarding these fields and their intersection in the experience of training and professional development in the Region of Inconfidentes and their social impact in understanding educational challenges. We understand that the actions organized by the research groups go beyond the frontiers of research through the formation and social insertion of subjects– teacher and studentin society. For this reason, it is important to promote education through in Networks Research, whether they are articulated with other educational institutions or within the research group itself, collaborating to improve education at regional and national levels.
EDUCAÇÃO ESPECIAL E LÍNGUA BRASILEIRA DE SINAIS NA FORMAÇÃO DE PROFESSORES DO CAMPO
Authors: Basso Jaqueline Daniela , Neres Celi Corrêa
Published: November 2020

Special Education is the right of all students with some type of disability; global disorder or high skills / giftedness, a modality present in all stages of Brazilian schooling, from day care to universities, regardless of where the school is located. Therefore, Special Education must take place both in urban schools and in rural schools. As for the specialized educational assistance of deaf students, he must be bilingual, in Brazilian Sign Language and Portuguese Language. Thus, in this study we aim to reflect on the interface between special education and rural education with an emphasis on the inclusion of Libras as a mandatory curricular component in teacher training courses for rural teachers. In order to achieve this objective, we use a bibliographic review; documentary analysis of part of the legislation governing Special Education and a case study of a qualitative and quantitative nature of a Special Degree Course in Pedagogy of the Earth through the documentary analysis of its Political Pedagogical Project and a questionnaire applied to a sample of its students. graduates. We conclude that the inclusion of the Libras discipline in undergraduate courses represents a gain for the deaf community and the possibility of training teachers aware of its importance for the bilingual schooling of deaf students and the educational rights of these students. However, it has not proved to be sufficient to make future teachers proficient in Libras, in this sense we suggest as possibilities the increase in the course load of courses, their deepening in teaching and extension projects and we point to the need for more research in the area.
USABILITY IN OPEN SOURCE SOFTWARE DEVELOPMENT: OPINIONS AND PRACTICE
Authors: Andreasen Morten Sieker , Nielsen Henrik Villemann , Schrøder Simon Ormholt , Stage Jan
Published: November 2020

Open Source Software (OSS) development has gained significant importance in the production of soft-ware products. Open Source Software developers have produced systems with a functionality that is competitive with similar proprietary software developed by commercial software organizations. Yet OSS is usually designed for and by power-users, and OSS products have been criticized for having little or no emphasis on usability. We have conducted an empirical study of the developers’ opinions about usability and the way usability engineering is practiced in a variety of OSS projects. The study included a questionnaire survey and a series of interviews, where we interviewed OSS contributors with both technical and usability backgrounds. Overall we found that OSS developers are interested in usability, but in practice it is not top priority, and OSS projects rarely employs systematic usability evaluation. Most of the efforts are based on common sense. Most developers have a very limited understanding of usability, and there is a lack of resources and evaluation methods fitting into the OSS paradigm.
High-Efficiency GaAs-Based Solar Cells
Authors: Yamaguchi Masafumi
Published: November 2020

The III-V compound solar cells represented by GaAs solar cells have contributed as space and concentrator solar cells and are important as sub-cells for multi-junction solar cells. This chapter reviews progress in III-V compound single-junction solar cells such as GaAs, InP, AlGaAs and InGaP cells. Especially, GaAs solar cells have shown 29.1% under 1-sun, highest ever reported for single-junction solar cells. In addition, analytical results for non-radiative recombination and resistance losses in III-V compound solar cells are shown by considering fundamentals for major losses in III-V compound materials and solar cells. Because the limiting efficiency of single-junction solar cells is 30-32%, multi-junction junction solar cells have been developed and InGaP/GaAs based 3-junction solar cells are widely used in space. Recently, highest efficiencies of 39.1% under 1-sun and 47.2% under concentration have been demonstrated with 6-junction solar cells. This chapter also reviews progress in III-V compound multi-junction solar cells and key issues for realizing high-efficiency multi-junction cells.
Elastic, Optical, Transport, and Structural Properties of GaAs
Authors: A. Tabbakh Thamer , M. Aljohany Raghad , Alhazmi Hatem , M. Alsulami Rawan
Published: November 2020

One of the major objectives of physics is to understand the physical properties of compound metals. Based on this very objective, in this chapter, we intend to review the physical as well as chemical properties of Gallium Arsenide material.
Editorial: We are Core
Authors: Weber Mary Beth
Published: November 2020

I belonged to the Association for Library Collections & Technical Services (ALCTS) (formerly Resources and Technical Services Division (RTSD)) for my entire professional career. It was my home in ALA, and where I forged relationships, learned valuable skills for my career, took advantage of continuing education offerings, and contributed to the profession through presentations, committee and task force work, and in editing ALCTS publications. And now, after considerable discussion and planning, ALCTS, along with the Library Leadership & Management Association (LLAMA) and the Library Information Technology Association (LITA), are now Core: Leadership, Infrastructure, Futures. This new division will draw on the strengths of the three former divisions. The Oxford English Dictionary provides various meanings for the word “core,” including “The central or innermost part, the ‘heart’ of anything,” and “a central portion that is cut out, or that remains after using the surrounding parts.” These definitions are quite appropriate and fitting for Core.
Tradução e adaptação transcultural da escala de atividade física para pessoas com deficiência física (PASIPD BR)
Authors: Rodrigues Douglas Felipe Veroni , Silva Fernanda Carolina Toledo da , Washburn Richard Avery , Braccialli Lígia Maria Presumido
Published: November 2020

A prática de atividade física regular é importante para proporcionar à pessoa com deficiência física bem-estar e melhor qualidade de vida. Observa-se uma carência de instrumentos padronizados e específicos na língua portuguesa para avaliação do nível de atividade física direcionados a essa população. O estudo teve como objetivo traduzir e adequar culturalmente o instrumento Physical Activity Scale for Individuals with Physical Disabilities – PASIPD para o português do Brasil. Para o processo de tradução e adaptação transcultural da escala, foram realizadas cinco etapas: 1) tradução inicial; 2) síntese da tradução; 3) retrotradução; 4) equivalência semântica e operacional; e, 5) Pré-teste. Na equivalência semântica, 7 itens obtiveram índice de concordância abaixo de 70%. No pré-teste o instrumento foi testado com adultos com deficiência física, por seis profissionais especialistas na área de Reabilitação Física. Nessa etapa apenas um item teve índice de concordância abaixo de 70%. Após a adequação dos itens que apresentaram dificuldade a escala foi considerada adequada culturalmente para verificar o nível de atividade física em indivíduos com deficiência física no Brasil.
L’inclusion comme théorie pratique
Authors: Plaisance Éric
Published: November 2020

Ao utilizar a expressão "prática", que Émile Durkheim adotou para projetar a pedagogia, a noção de inclusão é analisada criticamente, examinando seu caráter normativo de acordo com os seguintes aspectos: sua etimologia latina, seus usos iniciais nas políticas internacionais de educação e seu desenvolvimento rumo à valorização da diversidade; suas variações de significação conforme os países em função de suas políticas e suas instituições, tendo como exemplo a Inglaterra, a Itália e o Brasil; seus sentidos em relação às duas noções: a exclusão àquilo que se opõe; a integração demarcada; suas consequências paradoxais segundo as análises das ciências humanas e sociais contemporâneas, com e para além de Durkheim; as perspectivas de acessibilidade que concretizam a inclusão. Por fim, para superar as contradições da noção de inclusão, a acessibilidade pode ser mobilizada como um conceito unificador e operacional e como um novo ideal normativo.
Formation of the Rational Socio-Economic Worldview Based on the Laws of Nature and Society
Authors: N. Semin Alexander , A. Potekhin Nikolai , N. Potekhin Viktor
Published: November 2020

The study is aimed at the improvement of social and economic relations based on modern directions of the formation of a rational socio-economic worldview, eliminating the sociological contradictions of modern society. The use of a system-holistic interdisciplinary methodology determines the need to review the development tools of the problem of creating a rational worldview in society. The basis of the research methodology has become the conceptual matrix of the formation of a rational worldview according to community levels, taking into account the basic socio-economic law of human development in any system. The article presents the results of a study designed as a clarification of the concept of “rational worldview”, creating a list of the benefits of forming a rational socio-economic worldview based on the laws of nature and society, and determining the directions of formation of a rational worldview in the context of the topic under study. The results of the study can be used in the system of state management of economic processes.
Novelty/Originality of this study: (1) actualized, based on the systematization of scientific views, the theoretical provisions of the formation of a rational socio-economic worldview and determined the modern directions of its development; (2) the analysis of modern practices of the life of modern society is carried out and the logical and ideological contradictions in the field of behavioral economics are highlighted; (3) the conceptual apparatus of the category “rational worldview” has been clarified in the context of the contradictions in the functioning of socio-economic systems; (4) a conceptual matrix for the formation of a rational worldview has been developed; (5) the advantages of the formation of a rational worldview among the subjects of the development of society are formulated, based on social criteria analysis.
Framing Analysis of Village Funding Corruption in Media Suaramerdeka.Com in Central Java, Indonesia, 2019
Authors: Triyono Agus
Published: November 2020

Various corruption cases have occurred in many villages in Central Java, Indonesia. Corruption is mostly carried out by village officials in running the government. One of many factors causing such corruption cases is the existence of village fund assistance. These corruption cases have been published in the mass media, Specifically on online media, i.e. suaramerdeka.com
This study aims to look at the media framing of corruption cases that have occurred in Central Java, particularly concerning village funding assistance in various regions through the online media suaramerdeka.com.
This study is a constructive paradigm research. The approach method used is qualitative. Meanwhile, the analytical method used is the Robert N. Entman framing analysis model.
The findings of this study stated that suaramerdeka.com framed the perpetrators of corruption as village officials. Although it is acknowledged that not all of them are corrupt, the news seems to give the impression that village officials have conducted a lot of corruption. However, on the other hand, the news content of suaramerdeka.com as a local media in Central Java also lacks detail in reporting corruption issues. Moreover, it seems only normative and does not show that it is a strong media in covering corruption cases. The explanation of the news was not very in-depth.
The Drive and Nature of Internationalisation of Higher Education in Zambia
Authors: And Nelly Mwale Gift Masaiti
Published: November 2020

While internationalisation of higher education is a topical issue in globalscholarship, it attracts limited scholarly attention in the Zambian context.This article engages with the drive and nature of internationalisation ofhigher education in Zambia. Informed by a descriptive multi-site case studyof six higher education institutions (public and private) in which data werecollected through document analysis, interviews, and questionnaires, thearticle shows that internationalisation was largely motivated by economic,academic, and social and cultural factors. While limited and constrained,it was characterised by student and staff mobility, teaching and learningresources, and research and collaboration, with the context of Zambianhigher education shaping the motives for and nature of internationalisation.The article also argues that limited funding had implications for theinternationalisation of higher education in Zambia.
Monetary Policy and Macroprudential Regulation with Financial Frictions
Authors: Agénor Pierre-Richard
Published: November 2020

An integrated analysis of how financial frictions can be accounted for in macroeconomic models built to study monetary policy and macroprudential regulation.

Since the global financial crisis, there has been a renewed effort to emphasize financial frictions in designing closed- and open-economy macroeconomic models for monetary and macroprudential policy analysis. Drawing on the extensive literature of the past decade as well as his own contributions, in this book Pierre-Richard Agénor provides a unified set of theoretical and quantitative macroeconomic models with financial frictions to explore issues that have emerged in the wake of the crisis. These include the need to understand better how the financial system amplifies and propagates shocks originating elsewhere in the economy; how it can itself be a source of aggregate fluctuations; the extent to which central banks should account for financial stability considerations in the conduct of monetary policy; whether national central banks and regulators should coordinate their policies to promote macroeconomic and financial stability; and how much countercyclical macroprudential policies should be coordinated at the international level to mitigate financial spillovers across countries.

Agénor focuses on upper middle-income countries, which differ from advanced economies in terms of both their structural features (which include a financial sector dominated by banks, weak supervisory capacity, and a high degree of vulnerability to external shocks) and their long-standing policy challenges (such as managing volatile capital flows). Some of the analytical insights and broad policy lessons that can be drawn from the book will be of relevance to advanced economies as well.
BLOS1 mediates kinesin switch during endosomal recycling of LDL receptor
Authors: Zhang Chang , Hao Chanjuan , Shui Guanghou , Li Wei
Published: November 2020

Low-density lipoprotein receptor (LDLR) in hepatocytes plays a key role in plasma clearance of circulating LDL and in whole body cholesterol homeostasis. The trafficking of LDLR is highly regulated in clathrin-dependent endocytosis, endosomal recycling and lysosomal degradation. Current studies focus on its endocytosis and degradation. However, the detailed molecular and cellular mechanisms underlying its endosomal recycling are largely unknown. We found that BLOS1, a shared subunit of BLOC-1 and BORC, is involved in LDLR endosomal recycling. Loss of BLOS1 leads to less membrane LDLR and impairs LDL clearance from plasma in hepatocyte-specific BLOS1 knockout mice. BLOS1 interacts with kinesin-3 motor KIF13A, and BLOS1 acts as a new adaptor for kinesin-2 motor KIF3 to coordinate kinesin-3 and kinesin-2 during the long-range transport of recycling endosomes (REs) to plasma membrane along microtubule tracks to overcome hurdles at microtubule intersections. This provides new insights into RE’s anterograde transport and the pathogenesis of dyslipidemia.
High-quality genome assembly of Metaphire vulgaris
Authors: Jin Feng , Zhou Zhaoli , Guo Qi , Liang Zhenwen , Yang Ruoyu , Jiang Jibao , He Yanlin , Zhao Qi , Zhao Qiang
Published: November 2020

Earthworms enrich the soil and protect the health of their ecological environment. Previous studies on these invertebrates determined their protein content, hormone secretions, medicinal value, and ecological habits, but their whole genomic sequence remains incomplete. We performed whole genome sequencing of Metaphire vulgaris (Chen, 1930), which belongs to the genus Metaphire of the family Megascolecidae. The genome assembly was 729 Mb, with a N50 contig size of 4.2 Mb. In total, 559 contigs were anchored to 41 chromosomes according to the results of Hi-C (High-throughput Chromosome Conformation Capture) technology, which was confirmed by karyological analysis. A comparison of the genomic sequences and genes indicated that there was a whole-genome duplication in M. vulgaris followed by several chromosome fusion events. Hox genes and lumbrokinase genes were identified as partial clusters surrounding the genome. Our high-quality genome assembly of M. vulgaris will provide valuable information for gene function and evolutionary studies in earthworms.
Hydrocortisone inhibition of ascorbic acid transport by chromaffin cells
Authors: Levine Mark A. , Pollard Harvey B.
Published: July 2002

Adrenal chromaffin cells have been found to accumulate ascorbic acid by a saturable high affinity mechanism that is inhibited by hydrocortisone. The rate of ascorbic acid transport into cells was linear for at least 1 h and had a K
m of 103 μM, a value approaching the reported concentration of ascorbic acid in the adrenal vein during stress. The uptake process itself, representing net accumulation rather than exchange, was inhibited by 0°C, lack of sodium, ouabain, and by dinitrophenol and iodoacetate. Hydrocortisone but not the inactive analogue hydrocortisone hemisuccinate was found to inhibit ascorbic acid uptake in a reversible manner, with an ID
50 of 62 μM. This value was within the reported steroid concentration in the adrenal portal system during a significant stress. Both ascorbic acid and hydrocortisone are secreted from cortical cells during stress into the adrenal portal system and thus contact medullary chromaffin cells. We suggest that the control of ascorbic acid uptake by hydrocortisone indicates the existence of a heretofore unanticipated biochemical aspect of the adrenal stress response.
Mechanism of protein biosynthesis in prokaryotic cells
Authors: Pon Cynthia L. , Gualerzi Claudio O.
Published: July 2002

To define the step at which translational initiation factor IF1 excercises its stimulation, initial rate kinetic analyses of 30 S initiation complex formation were carried out in the presence and absence of this factor. It was shown that, without affecting the affinity of the ribosomes either for the initiator tRNA or for the poly(AUG) used as template, IF1 increases approximately 2.5‐fold the limiting V
maxof the ‘pre‐ternary complex’ ← ternary complex transition which represents the rate‐limiting step in 30 S initiation complex formation. This kinetic effect titrates with the 30 S ribosomal subunit which must therefore represent the target of IF1 action.
Bovine serum amine oxidase: a mammalian enzyme having covalently bound PQQ as prosthetic group
Authors: Lobenstein-Verbeek C.L. , Jongejan J.A. , Frank J. , Duine J.A.
Published: July 2002

In addition to the metal ion, copper‐containing amine oxidases possess an organic prosthetic group, the nature of which has long been controversial. We show here that in the case of bovine plasma amine oxidase, this second prosthetic group is covalently bound pyrroloquinoline quinone (PQQ). Until now the coenzyme PQQ has been found in several bacterial dehydrogenases. Thus the finding reported here is the first example of a quinoprotein oxidoreductase discovered in a eukaryotic organism.
Isolation and characterization of epidermal growth factor from human milk
Authors: Petrides Petro E. , Hosang Markus , Shooter Eric , Esch Frederic S. , Böhlen Peter
Published: July 2002

Epidermal growth factor (EGF) has been purified from human milk. The purification was monitored with a human placental membrane radioreceptor assay using murine salivary epidermal growth factor I (mEGF I) as a competitive ligand and was achieved exclusively by the use of reverse‐phase liquid chromatography (RPLC). The sequential use of preparative, semipreparative and analytical RPLC on an octylsilica support with solvent systems of different solute selectivity such as pyridine formate, triethylammonnium phosphate or perfluorocarbonic acids in the presence of n‐propanol or acetonitrile allowed purification to homogeneity with 5 consecutive runs. The molecular mass, amino acid composition and NH2‐terminal sequence of human EGF were determined. Gas‐phase microsequencing of residues 1‐17 revealed the following sequence: Asn ‐Ser‐Asp‐Ser‐Glu‐X‐Pro‐Leu‐Ser‐His‐Asp‐Gly‐Tyr‐X‐Leu‐X‐Asp which is identical with the NH2‐terminof urogastrone from human urine. The purified polypeptide competes with mEGF for the placental membrane receptor with a k
i, of 1 ng. Furthermore, it stimulates the anchorage‐dependent as well as ‐independent proliferation of human and rat indicator cells with half‐maximal stimulation at 1 and 2.5 , respectively. Although human epidermal growth factor has been unequivocally identified in human milk and ‐ for the first time ‐ shown to be identical with urogastrone from human urine, the high‐resolution techniques employed have also revealed the presence of EGF‐related molecules which await further characterization. It is possible that EGF and the EGF‐related growth factors possess important regulatory functions in normal growth of the human breast during pregnancy and lactation as well as in abnormal growth during mammary tumor formation and progression.
Cell nuclei generate DNA‐nicking Superoxide radicals
Authors: Peskin Alexander V. , Shlyahova Larisa
Published: July 2002

Rat liver nuclei generate Superoxide radicals in the presence of NADPH. Active oxygen species induced nicks in nuclear DNA. This was prevented by Superoxide dismutase and catalase as well as by anaerobiosis. EDTA‐Fe3+ dramatically increased the active oxygen‐dependent DNA nicking.
Detection and subcellular localization of a higher plant chorismate synthase
Authors: Mousdale David M. , Coggins John R.
Published: July 2002

Chorismate synthase (EC 4.6.1.4) was detected in tissue extracts and chloroplast preparations of pea (Pisum sativum L.) in the presence of reduced flavin generated by dithionite. Chorismate synthase and anthranilate synthase were present in intact chloroplasts isolated by density gradient centrifugation.
2,5‐Di(tert‐butyl)‐1,4‐benzohydroquinone — a novel inhibitor of liver microsomal Ca2+ sequestration
Authors: Moore Gregory A. , McConkey David J. , Kass Georges E.N. , O'Brien Peter J. , Orrenius Sten
Published: July 2002

Treatment of rat liver microsomes with 2,5‐di(tert‐butyl)‐1,4‐benzohydroquinone caused a dose‐related inhibition (K
i⋍1 μM) of ATP‐dependent Ca2+ sequestration. This was paralleled by a similar impairment of the microsomal Ca2+ ‐stimulated ATPase activity. In contrast, the hydroquinone failed to induce Ca2+ release from Ca2+ ‐loaded liver mitochondria (supplied with ATP), and inhibited neither the mitochondrial F1F0‐ATPase nor the Ca2+ ‐stimulated ATPase activity of the hepatic plasma membrane fraction. The inhibition of microsomal Ca2+ sequestration was not associated with any apparent alteration of membrane permeability or loss of other microsomal enzyme activities or modification of microsomal protein thiols. These findings suggest that 2,5‐di(tert‐butyl)‐1,4‐benzohydroquinone is a potent and selective inhibitor of liver microsomal Ca2+ sequestration which may be a useful tool in studies of Ca2+ fluxes in intact cells and tissues.
Oxidation of veratryl alcohol by the lignin peroxidase of Phanerochaete chrysosporium Involvement of activated oxygen
Authors: Haemmerli Stephan D. , Schoemaker Hans E. , Schmidt Harald W.H. , Leisola Matti S.A.
Published: July 2002

The oxidation of veratryl alcohol by the lignin peroxidase of Phanerochaete chrysosporium was studied. Five products were identified: veratraldehyde, two quinones and two aromatic ring cleavage lactones. A similar product pattern was obtained with the 1‐electron oxidant cerium(IV). Under anaerobic reaction conditions or in the presence of Mn(II) only traces of quinones or lactones were detected besides veratraldehyde. This indicates the involvement of activated oxygen species in the enzyme reaction. Possible mechanisms for the formation of the primary oxidation products from veratryl alcohol are discussed.
Triiodothyronine stimulates proliferation of osteoblast‐like cells in serum‐free culture
Authors: Ernst M. , Froesch E.R.
Published: July 2002

Primary rat ostcoblast‐like cells (Ob) were grown under strictly serum‐free conditions for up to 20 days. In the presence of triiodothyronine (T3) at concentrations of 0.01 and 0.1 nM, Ob proliferation was enhanced. Moreover, a decrease of alkaline phosphatase (AP) activity, a differentiation marker for Ob, was prevented, whereas protein synthesis (collagen and noncollagen protein) was decreased. T3 at much higher concentration (10 nM) had no significant effect on cell proliferation and matrix formation but decreased AP activity disproportionately. Thus, T3 at close to physiological concentrations stimulates growth and maintains differentiation of Ob.
Detection and enzymatic deglycosylation of a glycosylated variant of prolactin in human plasma
Authors: Champier Jacques , Claustrat Bruno , Sassolas Geneviève , Berger Michel
Published: July 2002

Immunoperoxidase electrophoresis was applied to the plasma of a patient showing a high level of prolactin (PRL) secreted by a pituitary adenoma. Two PRL monomers were detected with an anti‐hPRL antiserum: a major 22 kDa form and a minor 25 kDa form. Concanavalin A‐Sepharose 4B chromatography revealed that the 25 kDa form was a glycosylated variant of PRL. Incubation of this variant with endoglycosidase F led to its transformation into the 22 kDa form.
A nuclear yeast gene (GCY) encodes a polypeptide with high homology to a vertebrate eye lens protein
Authors: Oechsner Ulrich , Magdolen Viktor , Bandlow Wolfhard
Published: July 2002

We describe here the nuclear gene for a yeast protein showing unexpectedly high homology with mammalian aldo/keto reductases as well as with ϱ‐crystallin, one of the prominent proteins of the frog eye lens. Although it could be proven that the gene occurs as a single copy in the haploid yeast genome, replacement of the intact by a disrupted, nonfunctional allele led to no obvious phenotype, indicating that the gene is dispensable. The gene was assigned to chromosome XV. It is transcribed in vivo into an mRNA of about 1300 bases with a coding capacity for a protein of 312 amino acids (estimated M
r 35000).
Pertussis toxin inhibits cAMP surface receptor‐stimulated binding of [35S]GTPγS to Dictyostelium discoideum membranes
Authors: Snaar-Jagalska B.Ewa , De Wit Rene J.W. , Van Haastert Peter J.M.
Published: July 2002

GTP‐binding activity to Dictyostelium discoideum membranes was investigated using various guanine nucleotides. Rank order of binding activities was: GTPγS>GTP>8‐N3‐GTP; the binding of GTPγS and GTP, but not of 8‐N3‐GTP, was stimulated by receptor agonists. [3H]GTP binding to D. discoideum membranes has been described previously by a single binding type (K
d = 2.6 μM, B
max = 85 nM). More detailed studies with [35S]GTPγS showed heterogeneous binding composed of two forms of binding sites with respectively high (K
d = 0.2 μM) and low (K
d = 6.3 μM) affinity. cAMP derivatives enhanced GTPγS binding by increasing the affinity and the number of the high‐affinity sites, while the low‐affinity sites were not affected by cAMP. The specificity of cAMP derivatives for stimulation of GTPγS binding showed aclose correlation with the specificity for binding to the cell surface cAMP receptor. Pretreatment of D. discoideum cells with pertussis toxin did not affect basal GTP and GTPγS binding, but eliminated the cAMP stimulation of GTP and GTPγS binding. These results indicate that D. discoideum cells have a pertussis toxin‐sensitive GTP‐binding protein that interacts with the surface cAMP receptor, suggesting the functional interaction of surface receptor with a G‐protein in D. discoideum.
Sulfated N‐linked carbohydrate chains in porcine thyroglobulin
Authors: Kamerling Johannis P. , Rijkse Irma , Maas Augustinus A.M. , van Kuik J.Albert , Vliegenthart Johannes F.G.
Published: July 2002

N‐linked carbohydrate chains of porcine thyroglobulin were released by the hydrazinolysis procedure. The resulting mixture of oligosaccharide‐alditols was fractionated by high‐voltage paper electrophoresis, the acidic fractions were further separated by high‐performance liquid chromatography on Lichrosorb‐NH2, and analyzed by 500‐MHz 1H‐NMR spectroscopy and, partially, by permethylation analysis. Of the acidic oligosaccharide‐alditols, the following sulfated carbohydrate chains could be identified:
The metabolism of biphenyl structures in lignin by the soil bacterium (Pseudomonas paucimobilis SYK‐6)
Authors: Katayama Y. , Nishikawa S. , Murayama A. , Yamasaki M. , Morohoshi N. , Haraguchi T.
Published: July 2002

In the soil bacterium (Pseudomonas paucimobilis SYK‐6), the metabolism of DDVA (biphenyl structure of lignin) and syringic acid (characteristic aromatic ring in hardwood lignin) proceeds via a common intermediate, 3‐methylgallic acid. Protocatechuate is also an intermediate in the metabolism of vanillate and p‐hydroxybenzoic acid. 3‐Methylgallic acid and protocatechuate are the final aromatic intermediates in lignin microbial degradation and these compounds are substrates of protocatechuate‐4,5‐dioxygenase, which is a key enzyme in obtaining metabolic energy from various structures of lignin in this bacterium.
Drug targeting in Leishmania donovani infections using tuftsin‐bearing liposomes as drug vehicles
Authors: Guru P.Y. , Agrawal A.K. , Singha U.K. , Singhal A. , Gupta C.M.
Published: July 2002

The efficacy of sodium stibogluconate against Leishmania donovani infections was markedly enhanced by encapsulating this drug in tuftsin‐bearing liposomes. Also, pretreatment of the animals with these liposomes (free of drug) rendered them resistant to this infection, possibly by activating the host's macrophages. These results demonstrate that tuftsin‐bearing liposomes besides delivering the drug to the target cells could also enhance the nonspecific resistance against infections, thus offering an additional advantage over the use of tuftsin‐free liposomes as drug carriers in leishmania therapy.
Inhibition of poly(ADP‐ribosyl)ation does not prevent lymphocyte entry into the cell cycle
Authors: Marini Marina , Zunica Giovanna , Monti Daniela , Cossarizza Andrea , Ortolani Claudio , Franceschi Claudio
Published: July 2002

The enzyme poly(ADP‐ribosyl)transferase (ADPRT) becomes activated soon after a mitogenic stimulus is applied to lymphocyte cultures. It has also been reported that ADPRT inhibitors prevent cell proliferation when added to cultures at the same time as the mitogen. While this has been ascribed to the need to seal physiologically present DNA strand breaks before cells enter S phase, the presence of DNA strand breaks in quiescent human lymphocytes has been recently questioned. We demonstrate here that non‐toxic concentrations of ADPRT inhibitors do not affect lymphocyte blastization and proliferation, as measured by thymidine incorporation and cytofluorimetry. We therefore suggest that ADPRT activation is required for late functions which are not needed for cell cycle progression.
Molecular cloning and predicted full‐length amino acid sequence of the type Iβ isozyme of cGMP‐dependent protein kinase from human placenta
Authors: Sandberg Mårten , Natarajan Vasanti , Ronander Inger , Kalderon Daniel , Walter Ulrich , Lohmann Suzanne M. , Jahnsen Tore
Published: July 2002

In this study we report the isolation and characterization of three overlapping cDNA clones for the type Iβ isozyme of cGMP‐dependent protein kinase (cGK) from human placenta libraries. The composite sequence was 3740 nucleotides long and contained 58 nucleotides from the 5′‐noncoding region, an open reading frame of 2061 bases including the stop codon, and a 3′‐noncoding region of 1621 nucleotides. The predicted full‐length human type Iβ cGK protein contained 686 amino acids including the initiator methionine, and had an estimated molecular mass of 77 803 Da. On comparison to the published amino acid sequence of bovine lung Iα, human placenta Iβ cGK differed by only two amino acids in the carboxyl‐terminal region (amino acids 105–686). In contrast, the amino‐terminal region of the two proteins was markedly different (only 36% similarity), and human Iβ cGK was 16 amino acids longer. In a specific region in the amino‐terminus (amino acids 63–75), 12 out of 13 amino acids of the human Iβ cGK were identical to the partial amino acid sequence recently published for a new Iβ isoform of cGK from bovine aorta. Northern blot analysis demonstrated a human Iβ cGK mRNA, 7 kb in size, in human uterus and weakly in placenta. An mRNA of 7 kb was also observed in rat cerebellum, cerebrum, lung, kidney, and adrenal, whereas an mRNA doublet of 7.5 and 6.5 kb were observed in rat heart. Comparison of Northern and Western blot analyses demonstrated that the mRNA and protein for cerebellar cGK increased during the development of rats from 5 to 30 days old, whereas the 6.5 kb mRNA in rat heart declined.
Sequence divergence in a specific region of islet amyloid polypeptide (IAPP) explains differences in islet amyloid formation between species
Authors: Betsholtz Christer , Christmansson Lars , Engström Ulla , Rorsman Frederik , Svensson Viveka , Johnson Kenneth H. , Westermark Per
Published: July 2002

Amyloid deposits in the islets of Langerhans occur in association with type 2 diabetes mellitus (DM) in humans and cats and consist of a 37‐amino‐acid polypeptide known as islet amyloid polypeptide (IAPP). In order to find an explanation for the situation that islet amyloid (IA) does not develop in common rodent species, we have deduced the amino acid sequence of the IAPP molecule in mouse, rat and hamster. We find that a specific region of the molecule diverges to a high degree. Synthetic peptides corresponding to this region of human and hamster IAPP were compared for their ability to form amyloid fibrils in vitro. Whereas the human peptide readily formed fibrils with amyloid character, the hamster peptide completely lacked this property. We suggest this to be a likely explanation for the differences in IA formation between humans and rodents and discuss our findings in relation to the type 2 DM syndrome.
Neurotransmitter release
Authors: Zimmermann Herbert
Published: July 2002

Axon terminals release more than one physiologically active substance. Synaptic messengers may be stored in two different types of vesicles. Small electron‐lucent vesicles mainly store classical low molecular weight transmitter substances and the larger electron‐dense granules store and release proteins and peptides. Release of the two types of substances underlies different physiological control. Release of messenger molecules from axon terminals is triggered by influx of Ca2+ through voltage sensitive Ca2+ channels and a rise in cytosolic Ca2+ concentrations. Neither the immediate Ca2+ target(s) nor the molecular species involved in synaptic vesicle docking, fusion and retrieval are known. It is, however, likely that steps involved in the molecular cascade of transmitter release include liberation of vesicles from their association with the cytonet and phosphorylation by protein kinase C of proteins which have the ability to alter between membrane bound and cytoplasmic forms and thus facilitate or initiate the molecular interaction between synaptic vesicles and the plasma membrane.
Phytohormonal regulation of S‐adenosylmethionine synthetase and S‐adenosylmethionine levels in dwarf pea epicotyls
Authors: Mathur Mukul , Sachar R.C.
Published: July 2002

A significant stimulation (2‐ to 2.5‐fold) of AdoMet synthetase was witnessed in glibberellicd acid (GA3, 1μM)‐treated epicotyls of the dwarf pea (Pisum sativum). This was accompanied by a 2.4‐fold increase in the endogenous pool of S‐adenosylmethionine. Both abscisic acid (10 μM) and cycloheximide (20 ) inhibited the GA3‐mediated enhancement of AdoMet synthetase activity. Three isozymes of AdoMet synthetase were detected in GA3‐treated epicotyls, whereas a single activity peak was observed in controls. Thus, GA3 seems to control the induction of two new isozymes of AdoMet synthetase in the dwarf pea. By contrast, the tall pea exhibited three isozymes of AdoMet synthetase even in the absence of GA3 treatment. High concentration of L‐methionine (2 mM) mimicked the GA3‐elicited induction of two new isozymes of AdoMet synthetase in dwarf pea epicotyls.
Saturation kinetics of palmitate uptake in perfused skeletal muscle
Authors: Turcotte Lorraine P. , Kiens Bente , Richter Erik A.
Published: July 2002

We investigated the kinetics of palmitate uptake in a physiological skeletal muscle preparation by using the isolated perfused rat hindquarter. When plotted against the unbound plasma palmitate concentration, palmitate uptake displayed a simple Michaelis‐Menten relation with a calculated Vmax
and Km
of 16.3 nmol · min−1 · g−1 and 0.06 μmol·l−1, respectively. These results show that, as in isolated cell systems, uptake of free fatty acids in perfused skeletal muscle follows saturation kinetics consistent with carrier‐mediated membrane transport of free fatty acids.
Histidine decarboxylase gene expression in rat fundus is regulated by gastrin
Authors: Dimaline R. , Sandvik A.K.
Published: July 2002

The conversion of histidine to histamine by histidine decarboxylase (HDC) is of central importance in the control of vertebrate acid secretion. We have used PCR‐generated probes to study the regulation of HDC gene expression in rat fundic mucosa. When circulating gastrin levels were lowered by fasting or elevated by treatment with omeprazole, there were parallel changes in HDC mRNA abundance. However, when animals with elevated gastrin levels were concurrently treated with the gastrin/CCK‐B receptor antagonist PD 134308, HDC mRNA levels were not increased. These data are consistent with the hypothesis that HDC gene expression is regulated by gastrin, over the physiological range of circulating hormone concentrations.
Molecular cloning of a novel putative G‐protein coupled receptor expressed during rat spermiogenesis
Authors: Meyerhof Wolfgang , Müller-Brechlin Renate , Richter Dietmar
Published: July 2002

A cDNA clone encoding a novel putative G‐protein coupled receptor has been isolated from a rat testis cDNA library using a PCR‐amplified cDNA fragment as a hybridization probe. Northern blot analysis reveals that a corresponding 1.5 kb mRNA is exclusively expressed in testis. By in situ hybridization experiments this mRNA has been localized in spermatocytes and spermatids but not in spermatogonia, Leydig or sertoli cells. Ontogenic studies show that expression of the receptor‐encoding mRNA and sexual maturation are correlated reaching highest levels during the second and third months. Although the ligand for this receptor has not yet been identified, this receptor may play a role during reproduction.
Expression of the envelope antigen F1 of Yersinia pestis is mediated by the product of caf1M gene having homology with the chaperone protein PapD of Escherichia coli
Authors: Galyov E.E. , Karlishev A.V. , Chernovskaya T.V. , Dolgikh D.A. , Smirnov O.Yu. , Volkovoy K.I. , Abramov V.M. , Zav′yalov V.P.
Published: July 2002

The effective synthesis of the envelope antigen F1 of Y. pestis in E. coli HB101 is mediated by the expression of the caf1M gene. This gene was sequenced, and the protein encoded was found to have a significant homology with the chaperone protein PapD of uropathogenic E. coli. The data presented allow one to suppose Caf1M and PapD proteins perform similar functions in the biogenesis of the Y. pestis capsule and E. coli P‐pili, respectively.
Downregulation of collagen synthesis in fibroblasts within three‐dimensional collagen lattices involves transcriptional and posttranscriptional mechanisms
Authors: Eckes Beate , Mauch Cornelia , Hüppe Gabriele , Krieg Thomas
Published: July 2002

Culturing human fibroblasts in a three‐dimensional collagen matrix leads to a reduction of collagen I by more than 90%, both on the level of mRNA steady‐state as well as protein. In order to differentiate changes in de novo transcription and posttranscriptional control, nuclear run on assays and pulse/chase experiments determining mRNA stability were used. Our results indicate that de novo transcription of the COL1A1 gene and proα1(I)collagen mRNA half‐life are both decreased by 50% in fibroblasts grown in three‐dimensional collagen lattices as compared to monolayer cultures. The extracellular matrix therefore elicits signals which are transduced from the cell surface to the inside of fibroblasts resulting in a specific reprogramming of transcriptional as well as posttranscriptional processes.
2‐Oxo‐histidine as a novel biological marker for oxidatively modified proteins
Authors: Uchida Koji , Kawakishi Shunro
Published: July 2002

We report a promising finding that oxidative modification of proteins by free radicals could be monitored by the formation of oxidized histidine that is detectable by reverse‐phase HPLC with electrochemical detection (HPLC‐ECD). When the N‐protected histidine derivative (N‐benzoyl‐histidine) was exposed to a free radical‐generating system (copper/ascorbate), a number of products were detected by HPLC‐ECD and the main product among them was found to be identical to N‐benzoyl‐2‐oxo‐histidine. The acid hydrolysis of N‐benzoyl‐2‐oxo‐histidine provided a single product (2‐oxo‐histidine) that was detected sensitively by HPLC‐ECD. Thus 2‐oxo‐histidine was indeed generated as the main product in the oxidatively modified proteins by free radicals. Taken together, 2‐oxo‐histidine may be a useful biological marker for assessing protein modifications under oxidative stress.
Analysis of topoisomerase II‐mediated DNA cleavage of the c‐myc gene during HL60 differentiation
Authors: Riou Jean-François , Gabillot Michèle , Riou Guy
Published: July 2002

We have investigated the effect of mAMSA, a potent topoisomerase II inhibitor, on the c‐myc proto‐oncogene of the acute promyelocytic leukemia HL60 cell line during its differentiation. When HL60 cells were induced by dimethylsulfoxide (DMSO) to terminally differentiate, a rapid drop in the level of cmyc mRNA was observed, followed by an arrest of cell proliferation. In contrast, the level of topoisomerase II mRNA was transiently increased with a maximum at 6 h after DMSO addition and was then completely abolished after 48 h, indicating that topoisomerase II is activated during the onset of HL60 differentiation. In exponentially growing cells, treatment by mAMSA results in the formation of topoisomerase II‐mediated double strand DNA breaks in the c‐myc gene at positions where topoisomerase II would normally nick and reseal the two strands. In HL60 cells treated with both mAMSA and DMSO, the sites in the cmyc gene at which mAMSA had induced cleavage were not altered. However, a DNA cleavage site located at the end of the first c‐myc exon (position +3100), was strongly stimulated by mAMSA and DMSO treatment. This site fell within a DNase I hypersensitive region encompassing the MYC intron factor 1 (MIF1) binding site, where transcription elongation is normally blocked during differentiation. These data indicate that a change of topoisomerase II binding to critical regulatory region of the c‐myc gene is associated with the downregulation of this gene during differentiation.
Point mutation of glycine receptor α1 subunit in the spasmodic mouse affects agonist responses
Authors: Saul Brigitta , Schmieden Volker , Kling Claudia , Mülhardt Cornel , Gass Peter , Kuhse Jochen , Becker Cord-Michael
Published: July 2002

Homozygotic spasmodic (spd/spd) mice suffer from a motor disorder resembling poisoning by the glycine receptor antagonist strychnine. Here, a point mutation was identified in the glycine receptor α1 subunit gene of the spasmodic mouse which predicts an alanine‐to‐serine exchange at position 52 of the mature polypeptide. Upon expression in Xenopus laevis oocytes, α1A52S receptor channels displayed reduced responses to glycine, β‐alanine and taurine when compared to recombinant α1 glycine receptors. As glycine receptor content in spinal cord and native molecular weight appeared unaltered, this suggests that the spasmodic phenotype results from an altered neurotransmitter sensitivity of the mutant α1A52S subunit.