bluuebunny/crossref_metadata_2025 huggingface dataset:
Zwolnienie z obowiązku zapłaty składek ZUS lub
odroczenie ich płatności – ulgi systemowe czy
nadzwyczajne? Skutki prawne z uwzględnieniem
przepisów o pomocy publicznej
Authors: Pyssa Jacek
Published: April 2020

Przedmiotem tego artykułu jest analiza instytucji prawnych w postaci odroczenia płatności składek na system
zabezpieczenia społecznego w Polsce i zwolnienia z obowiązku opłacania tych składek podczas trwania epidemii
koronawirusa w celu ustalenia, czy ulgi te są systemowe, czy nadzwyczajne. Analiza wskazanych rozwiązań prowadzona
jest także w celu ustalenia, jakie są konsekwencje prawne odroczenia płatności składek lub zwolnienia
z obowiązku opłacania składek w świetle przepisów o pomocy pubicznej
Tricistronic Plasmid Expressing the T7 RNA Polymerase and Measles Virus N and P Proteins for Rescue of Measles Virus AIK-C Strain
Authors: Hoseini Seyed Amir Hosein , Ghaderi Mostafa , Gholami Alireza , Mousavi-Nasab Seyed Dawood , Purnoor Payam , Firouzjani Mohammad Hassan , Majidi Gharenaz Nasrin , Asadi Ava , Fazeli Maryam , Ahmadi Nayebali
Published: April 2020

: Up to now, several attenuated measles virus vaccine strains derived from the Edmonston B vaccine consisting of Schwarz/Moraten, Zagreb, and AIK-C have been introduced for the rescue of their relative viruses through reverse genetics. In most studies, the measles virus rescue was done by supplying a cell line that expresses T7 RNA polymerase and measles virus N and P proteins as accessory proteins. The present study aimed to evaluate the rescue efficiency of the recombinant measles virus AIK-C vaccine strain by using a tricistronic expression plasmid. In this study, the rescue of the recombinant measles virus AIK-C vaccine strain was performed by co-transfection of three plasmids, including the cloned antigenomic cDNA of measles virus, a tricistronic expression plasmid that contained T7 RNA polymerase and measles virus N and P genes, and measles virus L polymerase expression plasmid. To increase the rescue efficiency, the transfected HEK-293 cells were co-cultured with Vero cells. As a result, the use of tricistronic expression plasmid that concomitantly encoded three necessary genes for the rescue of the measles virus led to the viral cytopathic effect with high efficacy five days post-transfection. Finally, the co-culture of transfected HEK-293 cells with Vero cells showed a relatively fast induction of viral cytopathic effect.
The Relationship Between Internet Addiction and Social Adjustment, and Test Anxiety of the Students of Ardabil University of Medical Sciences
Authors: Naeim Mahdi , Rezaeisharif Ali , Zandian Hamed
Published: April 2020

Objectives: This study was conducted to determine the relationship between Internet addiction and social adjustment, and test anxiety among the female students of Ardabil University of Medical Sciences. Methods: This descriptive correlational research was conducted on all female students of Ardabil University of Medical Sciences studying in the second semester of the academic year 2019. The sample consisted of 346 students who were selected by simple random sampling. Data were collected using three questionnaires assessing Internet addiction, social adjustment, and test anxiety. The obtained data were analyzed using Pearson correlation and regression analysis. Results: The results showed that there was a significant positive correlation between Internet addiction and test anxiety. There is also an inverse correlation between social adjustment and test anxiety. The results of step-by-step regression analysis showed that among the variables under study, the Internet addiction variable predicts 0.32 and along with the social adjustment variable 0.37 variance of test anxiety. Conclusions: It can be concluded that the level of test anxiety in students can be controlled through the necessary training to make better use of the Internet and prevent its addiction.
Islamophobia and normative sociology
Authors: Modood Tariq
Published: April 2020

The concept of Islamophobia as anti-Muslim culturalism racism is establishing itself in social science and public discourse alike. Yet there is a tendency to focus on Muslims as an �Other�, an ascribed identity, at the expense of Muslim intersubjectivity and agency. �Othering� analysis also does not attend to how to distinguish between Islamophobia and reasonable criticism of Muslims and Islam. Moreover, the possibility of mutual criticism based on dialogue, as well as group intersubjectivity and agency are important for multicultural recognition and accommodation. The bringing out of the political significance of the latter is illustrative of a sociology which thinks of socio-political problems and solutions as existing within the same intellectual framework. Going further, such normative sociology makes explicit and justifies its normative presuppositions and prizes public intellectual engagement.
Cuestionario del Burnout Deportivo (ABQ): Análisis y validación en el deporte mexicano
Authors: Salazar González Dahiana , Cantú Berrueto Abril , López-Walle Jeanette M. , Berengüí Gil Rosendo
Published: April 2020

Athlete Burnout Questionnaire (ABQ; Raedeke y Smith, 2001) es un instrumento que mide el burnout específico en el deporte el cual se ha utilizado a nivel mundial. En México aún no se cuenta con un estudio que valide sus propiedades psicométricas, por ello, el objetivo de este estudio es validar el Cuestionario de Burnout Deportivo (ABQ) en el contexto mexicano, mediante el análisis de fiabilidad, validez factorial de segundo orden e invarianza factorial por género. Se evaluó a 2,612 deportistas con la versión al castellano (Balaguer, Castillo, Duda, Quested y Morales, 2011) del Cuestionario del Burnout Deportivo (ABQ; Athlete Burnout Questionnaire, Raedeke y Smith, 2001). Los resultados muestran fiabilidad; se confirma una estructura factorial de segundo orden y las cargas factoriales e interceptos se consideran invariantes entre hombres y mujeres. Se concluye que el ABQ es instrumento apropiado para las investigaciones e intervenciones en el deporte del contexto mexicano.

Athlete Burnout Questionnaire (ABQ, Raedeke and Smith, 2001) is an instrument that measures burnout in sport, widely spread and used worldwide. In Mexico there is still no study to validate its psychometric properties. Therefore, the objective of this study is to validate Cuestionario de Burnout Deportivo, evaluating reliability, factorial validity and factorial invariance by gender. We evaluated 2612 athletes with spanish version (Balaguer, Castillo, Duda, Quested and Morales, 2011) of Athlete Burnout Questionnaire (ABQ). The results show satisfactory levels of reliability, a second-order factor structure is confirmed and factor charges and intercepts are considered invariant between men and women. It is concluded that ABQ is an appropriate instrument for research and interventions in sport of Mexican context.

Athlete Burnout Questionnaire (ABQ; Raedeke e Smith, 2001) é um instrumento que mede o burnout específico no esporte, amplamente difundido e usado em todo o mundo. No México ainda não tem um estudo para validar as suas propriedades psicométricas, por conseguinte, o objectivo deste estudo consiste em validar o Questionário de neutralização Deportivo (ABQ) no contexto mexicano, avaliar a fiabilidade, validade fatorial de segunda ordem e a invariância fatorial por gênero. Foram avaliadas; 2612 atletas para a versão castelhana (Balaguer, Castillo, Duda, Quested e Morales, 2011) Burnout Questionário Deportivo (ABQ, Athlete Burnout Questionnaire, Raedeke e Smith de 2001). Os resultados mostram níveis satisfatórios de confiabilidade. A estrutura fatorial, cargas fatoriais e interceptos são considerados invariantes entre homens e mulheres. ABQ conclui-se que o instrumento adequado para pesquisas e intervenções no esporte do contexto mexicano.
Reassessing the observational evidence for nitrogen deposition impacts in acid grassland: spatial Bayesian linear models indicate small and ambiguous effects on species richness
Authors: Pescott Oliver L. , Jitlal Mark
Published: April 2020

Nitrogen deposition (Ndep) is considered a significant threat to plant diversity in grassland ecosystems around the world. The evidence supporting this conclusion comes from both observational and experimental research, with “space-for-time” substitution surveys of pollutant gradients a significant portion of the former. However, estimates of regression coefficients for Ndep impacts on species richness, derived with a focus on causal inference, are hard to locate in the observational literature. Some influential observational studies have presented estimates from univariate models, overlooking the effects of omitted variable bias, and/or have used P-value-based stepwise variable selection (PSVS) to infer impacts, a strategy known to be poorly suited to the accurate estimation of regression coefficients. Broad-scale spatial autocorrelation has also generally been unaccounted for. We re-examine two UK observational datasets that have previously been used to investigate the relationship between Ndep and plant species richness in acid grasslands, a much-researched habitat in this context. One of these studies (Stevens et al., 2004, Science, 303: 1876–1879) estimated a large negative impact of Ndep on richness through the use of PSVS; the other reported smaller impacts (Maskell et al., 2010, Global Change Biology, 16: 671–679), but did not explicitly report regression coefficients or partial effects, making the actual size of the estimated Ndep impact difficult to assess. We reanalyse both datasets using a spatial Bayesian linear model estimated using integrated nested Laplace approximation (INLA). Contrary to previous results, we found similar-sized estimates of the Ndep impact on plant richness between studies, both with and without bryophytes, albeit with some disagreement over the most likely direction of this effect. Our analyses suggest that some previous estimates of Ndep impacts on richness from space-for-time substitution studies are likely to have been over-estimated, and that the evidence from observational studies could be fragile when confronted with alternative model specifications, although further work is required to investigate potentially nonlinear responses. Given the growing literature on the use of observational data to estimate the impacts of pollutants on biodiversity, we suggest that a greater focus on clearly reporting important outcomes with associated uncertainty, the use of techniques to account for spatial autocorrelation, and a clearer focus on the aims of a study, whether explanatory or predictive, are all required.
JUVENTUDES EM POLÍTICAS PÚBLICAS: O ESTADO DA QUESTÃO EM PESQUISAS CEARENSES (2010-2016)
Authors: Fiuza Fialho Lia Machado , Sousa Francisca Genifer Andrade de
Published: April 2020

Objetiva-se compreender as principais discussões fomentadas nas pesquisas cearenses sobre as juventudes na interface com as políticas públicas locais. Metodologicamente utilizou-se a pesquisa do tipo estado da questão em quatro bases de dados com o descritor “juventudes”. Os resultados identificaram dezenove produtos que foram agrupados em quatro categorias após análise de conteúdo: “Trabalho e Educação”, “Violência e Cultura de Paz”, “Protagonismo Juvenil” e “Saúde e Sexualidade”. As discussões apontaram para a relevância de fomento às políticas públicas locais específicas, desde as necessidades e anseios juvenis, objetivando a inclusão e permanência dos jovens no ensino médio, formação cidadã e para o trabalho e fomento ao protagonismo para o enfrentamento das desigualdades.
Quality Evaluation of Oranges Stored in Evaporative Coolers
Authors: Balogun A. A. , Ariahu C. C. , Ojo M. O.
Published: April 2020

Large quantities of oranges are wasted during storage due to its highly perishable nature. Research was therefore conducted on quality evaluation of orange fruits stored in aluminum-cladded (ABBEC) and non-cladded burnt-clay-brick evaporative coolers (NBBEC) to prevent postharvest loss. Essentially, the evaporative coolers comprised of double burnt-brick walls (1.29 × 2.55 × 2.56 m) external and (1.13 × 1.27 × 2.08 m) internal, (L × W × H) with wet sand bed in between and a storage space of (1.13 × 0.36 × 1.32 m), (L × W × H). Metabolic rates of oranges were highest at ambient storage, intermediate in NBBEC with the least value in ABBEC. Beta carotene, ascorbic acid and acidity decreased while total soluble solids, pH and microbial loads increased during storage. ABBEC storage resulted in 4.0 to 5.3°C decrease in ambient temperature with corresponding higher relative humidity over the non-cladded burnt-clay-brick coolers.
Lewis Blood Group Percentage Distribution among Indigenes of Ogoni Ethnicity in Rivers State, Nigeria
Authors: Christian Serekara Gideon , Eze Evelyn Mgbeoma , Moore-Igwe Beatrice Wobiarueri
Published: April 2020

Aim: We attempted to determine the frequency and percentage distribution of Lewis blood group antigens among indigenes of Ogoni ethnicity in Rivers State, Nigeria.

Study Design: The study consisted of 101 Ogoni people, who were apparently healthy and free from transfusion transmissible infections confirmed by serological screening. Ogoniland is located along the Niger Delta Eastern edge, and to the north-east of the Imo River and Port Harcourt city. All subjects were recruited and their blood samples were collected. The presence of Lewis-a and -b (Lea/Leb) blood group was examined using Anti-Lea and Leb monoclonal antibody, respectively (Lorne Laboratories).

Results: Lea and Leb blood group was observed in 17.8% and 11.9%, respectively.

Conclusion: Lea and Leb in this population was observed less frequently than those in other population previously reported. The Lewis antigen was reported to be associated with thrombotic disorders and Helicobacter pylori infection. Further studies may be directed to examine the association between Lewis blood group antigens and the risk of these conditions in Ogoni subjects.
Effects of solubilisation on some properties of the membrane‐bound respiratory enzyme D‐amino acid dehydrogenase of Escherichia coli
Authors: Jones H. , Venables W.A.
Published: July 2002

Solubilisation, delipidation and partial purification of the membrane‐bound enzyme. D‐amino acid dehydrogenase of Escherichia coli K 12 produced significant changes in several of its properties. Solubilised enzyme showed a broader substrate specificity, increased affinity for at least three substrates, and a lower pH optimum with D‐alanine as substrate. Solubilised enzyme was more heat‐labile than native enzyme, particularly at 37°C, and re‐binding to envelope preparations restored protection against heat denaturation. Activity of delipidated enzyme could be increased by addition of pure phospholipids. Native enzyme showed biphasic Arrhenius kinetics associated with phase changes of membrane lipids.
Characterization and synthesis of a macrophage inhibitory peptide from the second constant domain of human immunoglobulin G
Authors: Auriault Claude , Joseph Michel , Tartar André , Capron André
Published: July 2002

We have shown that IgG hydrolysed by Schistosoma mansoni schistosomula inhibited various macrophage functions, especially phagocytosis and anti‐schistosome cytotoxicity. Here we show that a tripeptide, Thr289‐Lys‐Pro291, of the second constant domain of human immunoglobulin G (peptide 286–292) reproduced the inhibitory effect of a total hydrolysate. Indeed the β‐glucuronidase release from IgE‐anti‐IgE‐stimulated rat and human macrophages decreased and its intracellular level did not rise after a prior incubation of the cells with Thr‐Lys‐Pro (500 nmol/ml). Moreover, the cell migration as well as the superoxide anion O−
2 generation were 50–80% reduced by the tripeptide. These results suggest that a single peptide set may be responsible for the decrease of the macrophage functions at the early stage of the parasite infection in the mammalian host. The pharmacologic properties of this tripeptide are under investigation.
Nitrate, but not silver, ions induce spectral changes in Escherichia coli cytochrome d
Authors: Hubbard Julia A.M. , Hughes Martin N. , Poole Robert K.
Published: July 2002

The absorbance maximum (630 nm) of reduced cytochrome d in Escherichia coli membrane particles was diminished by 160 μM AgNO3 or NaNO3 and accompanied by the formation of a species with an absorption maximum at 640–645 nm. Nitrite, trioxodinitrate and nitric oxide elicited qualitatively similar, but faster, changes in the spectrum of cytochrome d, suggesting that formation of a nitrosyl complex may be involved in all cases. In direct contrast to an earlier report, silver ions (160 υM) were without effect on the α‐bands of reduced cytochromes d, b or a
1.
[4,4′‐D‐Diaminopropionic acid]gramicidin S: a synthetic gramicidin S analog with antimicrobial activity against Gram‐negative bacteria
Authors: Ando Shoji , Aoyagi Haruhiko , Shinagawa Susumi , Nishino Norikazu , Waki Michinori , Keto Tetsuo , Izumiya Nobuo
Published: July 2002

Gramicidin S is especially active against Gram‐positive bacteria; e.g., Staphylococcus aureus. An analog, [4,4′‐D‐diaminopropionic acid]gramicidin S, which contains D‐diaminopropionic acid residues instead of D‐phenylalanine residues, has been synthesized. This analog is active against some of the Gram‐negative bacteria; e.g., Escherichia coli and Salmonella typhosa. Activities of several related analogs are discussed.
Evidence for two dinstinct pyruvate kinase genes in Escherichia coli K‐12
Authors: Garrido-Pertierra Amando , Cooper Ronald A.
Published: July 2002

A strain of Escherichia coli K‐12 defective in pyruvate kinase F has been produced. The existence of this mutant, in conjunction with earlier results, strongly suggests that the two pyruvate kinases in this bacterium are distinct forms and not interconvertible. Either form of pyruvate kinase appeared to be equally effective in the glycolytic conversion of phosphoenolpyruvate to pyruvate. Genes specifying pyruvate kinase A and pyruvate kinase F were present on the small F‐prime F506 and the locus for pyruvate kinase F was found to be at minute 36.5 on the E. coli genetic map.
Myosin isozyme changes in the heart following constriction of the ascending aorta of a 25‐day old rat
Authors: Bugaisky Lawrence B. , Siegel Elisabeth , Whalen Robert G.
Published: July 2002

When a constricting band is placed around the ascending aorta of young (25‐day old) rats, all chambers of the heart eventually produce hypertrophy. Both the left and right ventricles show strong shifts toward an isozyme pattern in which V3 is predominant, similar to that seen in models were hypertrophy is induced in adult rats. The hypertrophied atria however, show no detectable change in the native myosin isozymes or the light chain subunits.
Aldehydic peptides inhibiting renin
Authors: Fehrentz Jean-Alain , Heitz Annie , Bertrand Castro , Cazaubon Catherine , Nisato Dino
Published: July 2002

Aldehydic peptides in which the C terminal residue is leucinal or phenylalaninal were synthesized. These compounds exhibited potent inhibition of renin activity and appeared to be precursors of transition state analogues for renin‐catalysed amide bond hydrolysis.
Characteristics of ATPase activity and the subunit composition of myosin in the conduction system of bovine heart
Authors: Tamura Yoshiyuki , Nishimoto Tetsuo , Miyakami Sciji , Sako Harunobu , Saito Ken , Mori Hiroyoshi
Published: July 2002

The ATPase activity, light chains and isoenzymes of myosin from specialized myocardial tissue (the A‐V node, bundle of His, and right and left bundle branches) of bovine heart were compared with those of atrial and ventricular myosins. The order of Ca2+‐activated ATPase activity was atrial ⪢ specialized myocardial tissue ⪢ ventricular myosin. SDS‐polyacrylamide gel electrophoresis showed that myosin from the specialized myocardial tissue contained the light chains of both atrial and ventricular myosins. On the other hand, the specialized myocardial tissue contained one V3 isomyosin and showed no difference from ventricular myocardial tissue on pyrophosphate gel.
Isolation and chemical conversion of two novel prostaglandin endoperoxides: 5(6)‐epoxy‐PGG1 and 5(6)‐epoxy‐PGH1
Authors: Oliw Ernst H.
Published: July 2002

5(6)‐Epoxy‐PGG1 and 5(6)‐epoxy‐PGH1 were isolated after incubation of microsomes of RSV with 3H‐labelled 5(6)‐epoxy‐C20:3 for 45 s at 37°C. The endoperoxides were methylated and characterized by conversion to prostaglandins. In buffer, the endoperoxides were converted to methyl‐5(6)‐epoxy‐PGE1 and methyl‐5(6)‐epoxy‐15‐hydroperoxy‐PGE1, while treatment with SnCl2 reduced the endoperoxides to methyl‐5‐hydroxy‐PGI1α and methyl‐5‐hydroxy‐PGI1β. Significant amounts of methyl‐5(6)‐epoxy‐HHD were also formed. The endoperoxides could be separated by silicic acid chromatography and when 1 mM phenol was present in the incubation, 5(6)‐epoxy‐PGH1 was obtained as the main product.
The influence of thyroid hormone on the degree of control of oxidative phosphorylation exerted by the adenine nucleotide translocator
Authors: Holness M. , Crespo-Armas A. , Mowbray J.
Published: July 2002

Adenine nucleotide translocator
Control strength
Liver mitochondria
Oxidative phosphorylation
Triiodothyronine
β‐Granins: 21 kDa co‐secreted peptides of the insulin granule closely related to adrenal medullary chromogranin A
Authors: Hutton John C. , Hansen Frede , Peshavaria Mina
Published: July 2002

Three closely related forms of a 21 kDa protein which is co‐secreted with insulin have been purified and analysed. These differed in behaviour on ion‐exchange chromatography but were indistinguishable by their susceptibility to staphylococcal V8 proteinase digestion, amino acid composition or N‐terminal amino acid sequence. Their amino acid composition and N‐terminal sequences were remarkably similar to adrenal medullary chromogranin A, a much larger protein (72 kDa). Antibodies to chromogranin A also reacted strongly with the 21 kDa protein in isolated insulin granules. It is concluded that the 21 kDa proteins either represent a repeated domain within the chromogranin molecule or a closely related gene product. The name β‐granin is proposed for these proteins.
Interaction between the mitochondrial ATP synthetase and ATPase inhibitor protein
Authors: Panchenko Maria V. , Vinogradov Andrei D.
Published: July 2002

The rate of mitochondrial ATPase inactivation by the naturally occurring inhibitor protein in the presence of saturating ATP and Mg2+ at pH 8.0 depends hyperbolically on the amount of inhibitor added; the upper limit of an apparent first‐order constant for the inactivation process is 1.0−1 at 25°C. A dramatic difference in the inactivation rate is observed when the protein inhibitor is added to the same assay system from either acidic (pH 4.8) or alkaline (pH 8.2) solutions. The slow reversible transition of the inhibitor from its rapidly reacting ‘acidic’ form to the slow reacting ‘alkaline’ form occurs when the solution of the protein inhibitor is subjected to a pH‐jump from 4.8 to 8.2 (t
½ ~ 30 s at 25°C). The pH‐profile of the inhibitor active/inactive equilibrium suggests that a group with pK
a ~ 6.5 is involved in the transition. Treatment of the inhibitor protein with a histidine‐specific reagent (e.g. diethyl pyrocarbonate) abolishes its inactivating effect on the ATPase activity. It is concluded that the protonation/deprotonation of the inhibitor protein followed by its slow conformational changes is the rate‐limiting step in the inhibitor‐ATP synthetase interaction.
Very low density lipoprotein triglyceride kinetics during hepatic lipase suppression by estrogen
Authors: Tikkanen M.J. , Kuusi T. , Nikkilä E.A. , Sane T.
Published: July 2002

The exact role of the heparin‐releasable hepatic endothelial lipase has remained controversial. It has been suggested that it acts in concert with lipoprotein lipase in the step‐wise delipidation of triglyceride‐rich lipoproteins. On the other hand, there is evidence indicating that high density Iipoprotein2 is the preferred substrate for hepatic lipase. Here, it is shown that a moderate (27%) suppression of hepatic lipase activity by estrogen did not impair removal of 3H‐labeled very low density lipoproteins (VLDL) triglycerides, suggesting that this enzyme is not a major regulator of VLDL catabolism under physiological circumstances.
Meta‐vinculin distribution in adult human tissues and cultured cells
Authors: Glukhova M.A. , Kabakov A.E. , Belkin A.M. , Frid M.G. , Ornatsky O.I. , Zhidkova N.I. , Koteliansky V.E.
Published: July 2002

Meta‐vinculin distribution in adult human tissue was studied by immunoblotting technique. Meta‐vinculin was found in smooth (aorta wall and myometrium) and cardiac muscle, rather than in skeletal muscle, liver, kidney and cultured cells ‐ macrophages, foreskin fibroblasts, peripheral blood lymphocytes and vascular endothelial cells. In the primary culture of smooth muscle cells from human aorta the meta‐vinculin/vinculin ratio was reduced, and on the onset of cell division meta‐vinculin could hardly be detected. Subcultured smooth muscle cells from human aorta did not contain meta‐vinculin. The data show that the presence of meta‐vinculin is characteristic of'contractile' smooth muscle cells rather than of proliferating in vitro.
Potentiation and inhibition of secretion from neutrophils by phorbol ester
Authors: Barrowman M.M. , Cockcroft S. , Gomperts B.D.
Published: July 2002

We demonstrate that PMA exhibits multiple effects on fMetLeuPhe and ionophore‐mediated secretion from rabbit and human neutrophils: (i) Inhibition of receptor‐mediated secretion appears to take place at an early stage in the stimulus‐secretion coupling sequence since PMA inhibits the formation of phosphatidate. (ii) Protein phosphorylation is observed with both PMA and fMetLeuPhe and the extent of phosphorylation is additive in the presence of both stimuli, (iii) Another possible site of regulation by PMA lies distal to the rise in cytosolic Ca2+. This is indicated by the enhancement or inhibition by PMA of the A23187‐induced secretory response at low and high external Ca2+ concentrations, respectively.
Purification and characterization of recombinant murine immune interferon
Authors: Nagata Kiyoshi , Kikuchi Norihisa , Ohara Osamu , Teraoka Hiroshi , Yoshida Nobuo , Kawade Yoshimi
Published: July 2002

The recombinant murine immune interferon (rMu‐IFN‐γ) was purified to homogeneity from Escherichia coli harboring the expression vector of murine IFN‐γ. The purified rMu‐IFN‐γ showed an M
r of 15000 in SDS‐polyacrylamide gel electrophoresis. Results of amino acid analysis, amino‐ and carboxyl‐terminal analyses and peptide mapping of rMu‐IFN‐γ suggest that it has the complete protein sequence predicted on the basis of cDNA except for lack of four amino acid residues from the mature carboxyl‐terminus.
Antithrombin properties of C‐terminus of hirudin using synthetic unsulfated Nα‐acetyl‐hirudin45–65
Authors: Krstenansky John L. , Mao Simon J.T.
Published: July 2002

Unsulfated N
α‐acetyl‐hirudin45–65 (MDL 27 589), which corresponds to the C‐terminus of hirudin1–65, was synthesized by solid‐phase methods. The synthetic peptide was able to inhibit fibrin formation and the release of fibrinopeptide A from fibrinogen by thrombin. The catalytic site of thrombin was not perturbed by the synthetic peptide as H‐D‐Phe‐Pip‐Arg‐pNA hydrolysis (amidase activity) was not affected. The binding of synthetic peptide and thrombin was assessed by isolation of the complex on gel‐filtration chromatography. A single binding site with a binding affinity (K
a) of approx. 1.0 × 105 M−1 was observed for thrombin‐hirudin45–65 interaction. The data suggest that the C‐terminal residues 45–65 of hirudin contain a binding domain which recognizes thrombin and yet does not bind to the catalytic site of the enzyme.
Effects of phosphorylation of inhibitory GTP‐binding protein by cyclic AMP‐dependent protein kinase on its ADP‐ribosylation by pertussis toxin, islet‐activating protein
Authors: Watanabe Yasuhiro , Imaizumi Taro , Misaki Naoyuki , Iwakura Katsuomi , Yoshida Hiroshi
Published: July 2002

Pretreatment of rat cardiac myocytes with the β‐adrenergic agonist, db‐cAMP or forskolin decreased ADP‐ribosylation of 40–41 kDa protein by islet‐activating protein (IAP) in cell membranes. Addition of activated cyclic AMP‐dependent protein kinase (protein kinase A) catalytic subunit and MgCl2 also decreased ADP‐ribosylation of 40–41 kDa protein by IAP in cell membranes. The α‐ and β‐subunits of partially purified inhibitory GTP‐binding protein (Gi) were both phosphorylated by protein kinase A. The amounts of phosphate incorporated into the subunits of Gi were 0.34 and 0.18 mol/mol protein. These show that phosphorylation of Gi by protein kinase A results in a decrease in its ADP‐ribosylation by IAP.
Heat‐induced changes in the conformation of α‐ and β‐crystalline: Unique thermal stability of α‐crystallin
Authors: Maiti Motilal , Kono Masahiro , Chakrabarti Bireswar
Published: July 2002

Of the crystallin proteins of the lens, the principal subunit of the β‐crystallin, βB2 (βBp), has been considered to be the only heat‐stable protein because it does not precipitate upon heating. In our recent investigations, however, we have found that the α‐crystallin from bovine lenses is not only heat stable but also does not denature at temperatures up to 100°C. Using circular dichroism and fluorescence to monitor the conformational changes of α‐ and βB2‐crystallins upon heating, we found that α‐crystallin maintains a high degree of structure, whereas the βB2‐crystallin shows a reversible sigmoidal order‐disorder transition at about 58°C.
Degradation of epidermal growth factor receptors by cathepsin L‐like protease: Inhibition of the degradation by c‐Ha‐ras gene products
Authors: Hiwasa Takaki , Sakiyama Shigeru , Yokoyama Shigeyuki , Ha Jong-Myung , Noguchi Shigeru , Bando Yoshiaki , Kominami Eiki , Katunuma Nobuhiko
Published: July 2002

Extract of N1H3T3 mouse fibroblasts contains a protease which can cleave epidermal growth factor receptor (EGF receptor). This protease was tentatively named cathepsin X and purified to near homogeneity. The characteristics of cathepsin X were similar to those of cathepsin L and the proteolytic activity of cathepsin X was inhibited by c‐Ha‐ras gene products.
Stimulation and inhibition of human platelet membrane high‐affinity GTPase by neomycin
Authors: Herrmann Eva , Jakobs Karl H.
Published: July 2002

The effect of the inositol phospholipid‐binding antibiotic neomycin was studied on high‐affinity GTPase in human platelet membranes. At low concentrations (up to 1 mM), neomycin by itself stimulated a high‐affinity GTPase. This GTPase stimulation was additive with that caused by the hormonal factors, prostaglandin E1 and epinephrine, but not with thrombin. At concentrations higher than 1 mM, neomycin reduced control GTPase activity and eliminated the stimulation caused by thrombin. The data suggest that neomycin by a presently unknown mechanism can regulate activity states of signal transducing GTP‐binding proteins.
Phorbol ester modulates serotonin receptor‐mediated increases in inositol phosphate production and calcium mobilization in cultured rat vascular smooth muscle cells
Authors: Takata Shoichiro , Hirata Yukio , Takagi Yasuyuki , Yoshimi Hiroki , Fukuda Yuka , Fujita Takuo
Published: July 2002

The effect of 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) on serotonin‐induced inositol phosphate (IP) accumulation and intracellular free Ca2+ concentrations ([Ca2+]i) was investigated in cultured rat vascular smooth muscle cells. Pretreatment with TPA had no effect on basal levels of both IP production and [Ca2+]i, whereas it significantly attenuated serotonin‐induced increases in both IP production and [Ca2+]i. These data suggest that protein kinase C is involved in the negative feedback control of serotonin‐induced rises in both IP production and [Ca2+]i.
Isolation and sequencing of a cDNA clone encoding 107 kDa sialoglycoprotein in rat liver lysosomal membranes
Authors: Himeno Masaru , Noguchi Youichiro , Sasaki Hiroyuki , Tanaka Yoshitaka , Furuno Koji , Kono Akira , Sakaki Yoshiyuki , Kato Keitaro
Published: July 2002

A cDNA for 107 kDa sialoglycoprotein (LGP 107), the major protein component of rat liver lysosomal membranes, was isolated and sequenced. The 1.8 kbp cDNA contained an open reading frame encoding a polypeptide consisting of 386 amino acid residues (M
r 41914). The deduced NH2‐terminal 10‐residue sequence is identical with that determined for purified LGP 107. The primary structure deduced for LGP 107 contains 20 potential N‐glycosylation sites and exhibits 82.5, 43 and 60% sequence similarities to mouse LAMP‐1, chicken LEP 100, and a 120‐kDa human lysosomal glycoprotein, respectively. Among these lysosomal glycoproteins, the amino acid sequence of the putative transmembrane segment is highly conserved. Northern blot hybridization analysis identified a single species of LGP 107 mRNA (2.1 kbp in length) in rat liver, kidney, brain, lung, spleen, heart and pancreas, although its level in pancreas was very low.
Collagenase gene expression in fibroblasts is regulated by a three‐dimensional contact with collagen
Authors: Mauch Cornelia , Adelmann-Grill Bernhard , Hatamochi Atsushi , Krieg Thomas
Published: July 2002

Collagenase activity in fibroblasts is regulated by cytokines and the interaction with the extracellular matrix. In this study we demonstrate that fibroblasts cultured within a three‐dimensional collagen gel show a strong induction of collagenase gene expression. In addition to increased de novo synthesis most of the secreted enzyme was found to be activated leading to a high collagenolytic activity and complete degradation of collagen matrices after removal of fetal calf serum. Collagen I gene expression was found to be reduced under these conditions. These data suggest a specific modulation of cellular metabolism in response to contact with a three‐dimensional collagenous matrix resulting in the divergent regulation of collagen and collagenase.
Characterization of cDNA clones encoding two putative isoforms of the α1 subunit of the dihydropyridine‐sensitive voltage‐dependent calcium channel isolated from rat brain and rat aorta
Authors: Koch Walter J. , Hui Anna , Shull Gary E. , Ellinor Patrick , Schwartz Arnold
Published: July 2002

cDNA clones encoding rat brain and rat aorta isoforms of the α1 subunit of the dihydropyridine‐sensitive, voltage‐dependent calcium channel were isolated and sequenced. These tissue‐specific cDNA clones share significant amino acid similarity with the rabbit skeletal muscle calcium channel α1 subunit (75% and 66% amino acid identity for rat brain and rat aorta isoforms, respectively). Northern analysis revealed transcript sizes of 6.5 and 8.6 kb in aorta and 8.6 kb in brain.
Potentiometric titration of cytochrome‐bo type quinol oxidase of Escherichia coli: Evidence for heme‐heme and copper‐heme interaction
Authors: Salerno John C. , Bolgiano Barbara , Ingledew W.John
Published: July 2002

The cytochrome‐bo quinol oxidase of Escherichia coli contains a high‐spin b‐type heme (cytochrome o), a low‐spin b‐type heme (cytochrome b) and copper. The EPR signal from cytochrome o is axial high spin and when titrated potentiometrically gives a bell‐shaped curve. The low‐potential side of this curve (E
m7 approx. 160 mV) corresponds to the reduction/oxidation of the cytochrome. The high‐potential side (E
m7 approx. 350 mV) is proposed to be due to reduction/oxidation of a copper center; in the CuII form tight cytochrome o‐copper spin coupling results in a net even spin system and loss of the EPR spectrum. Optical spectra of the α‐bands of the reduced cytochromes at 77 K show that cytochrome b has its maxima at 564 nm when cytochrome o is oxidized but that this shifts to 561 nm when cytochrome o (max. 555 nm) is reduced. Both a heme‐copper (cytochrome o‐CuII) and a heme‐heme (cytochrome o‐cytochrome b) interaction are indicated in this quinol oxidase. These results indicate that cytochrome‐bo quinol oxidase has a binuclear heme‐copper catalytic site and suggest striking structural similarity to subunit I of the cytochrome aa
3 system.
Fibrinogen is chemotactic for vascular smooth muscle cells
Authors: Naito Michitaka , Hayashi Toshio , Kuzuya Masafumi , Funaki Chiaki , Asai Kanichi , Kuzuya Fumio
Published: July 2002

We studied the effect of fibrinogen on the migration of bovine aortic smooth muscle cells in culture, using a Neuro Probe 48‐well micro chemotaxis chamber. Fibrinogen stimulated the migration of the cells dose‐dependently at concentrations from 30 to 1OOO μg/ml. A modified checkerboard analysis of the response demonstrated that the effect was largely chemotactic in nature. The present results suggest that fibrinogen may play an important role in the pathogenesis of arterial intimal thickening and atherosclerosis.
SRTX‐d, a new native peptide of the endothelin/sarafotoxin family
Authors: Bdolah A. , Wollberg Z. , Fleminger G. , Kochva E.
Published: July 2002

Sarafotoxin; Endothelin; Snake venom; Aorta
Expression in Escherichia coli of a sub‐gene encoding the lipoyl domain of the pyruvate dehydrogenase complex of Bacillus stearothermophilus
Authors: Dardel Frédéric , Packman Leonard C. , Perham Richard N.
Published: July 2002

A sub‐gene encoding the lipoyl domain (residues 1–85) of the lipoate acetyltransferase chain of the pyruvate dehydrogenase complex of Bacillus stearothermophilus was over‐expressed in Escherichia coli. Approx. 80% of the domain was unlipoylated but most of the remainder was correctly lipoylated on Lys‐42 and could be reductively acetylated by the B stearothermophilus enzyme complex. A small proportion (approx. 4%) of the domain carried an aberrant substituent, possibly an octanoyl group, on Lys‐42. The 400 MHz 1H NMR spectra of the lipoylated and unlipoylated domains were essentially identical and closely resembled that of the native lipoyl domain.
Monoclonal antibody to desmin purified from cow Purkinje fibers reveals a cell‐type specific determinant
Authors: Virtanen I. , Närvänen O. , Thornell L.-E.
Published: July 2002

We have raised monoclonal antibodies (Mab) to the M
r 55000 desmin polypeptide, electrophoretically purified from cytoskeletal preparations of isolated bovine heart Purkinje fibers. One of the Mabs, 39AB6, revealed desmin only in cow Purkinje fibers and did not react with desmins from other muscle cells, including ventricular cardiac muscle, striated muscle and smooth muscle, as revealed by both immunoblotting and immunocytochemistry. Desphosphorylation of electrophoretically separated polypeptides on nitrocellulose with alkaline phosphatase did not affect the binding of the Mab. The present results show that there are cell‐type specific antigenic determinants in intermediate proteins of the desmin type.
Protein kinase C during differentiation of human promyelocytic leukemia cell line, HL‐60
Authors: Hashimoto Keisuke , Kishimoto Akira , Aihara Hiroaki , Yasuda Ichiro , Mikawa Katsuya , Nishizuka Yasutomi
Published: July 2002

Protein kinase C (PKC) from human promyelocytic leukemia HL‐60 cells can be resolved into three fractions (peak a, b and c) by hydroxyapatite column chromatography. Peak a and c enzymes are indistinguishable from the brain type II PKC having β (βI and βII)‐sequence and type III having α‐sequence, respectively. Peak b enzyme is a previously unidentified PKC subspecies that has enzymological properties subtly different from type I (having γ‐sequence), type II and type III PKC. Upon treatment of HL‐60 cells with 1 μM retinoic add, this peak b enzyme is decreased dramatically within 24 h, whilst peak a enzyme (β‐PKC) is increased, and peak c (α‐PKC) enzyme is slightly decreased within 48 h. The result implies that the PKC subspecies in HL‐60 cells have distinct functions during cell differentiation.
Erbstatin blocks platelet activating factor‐induced protein‐tyrosine phosphorylation, polyphosphoinositide hydrolysis, protein kinase C activation, serotonin secretion and aggregation of rabbit platelets
Authors: Salari Hassan , Duronio Vincent , Howard Sandra L. , Demos Michelle , Jones Kelvin , Reany Anne , Hudson Alan T. , Pelech Steven L.
Published: July 2002

The role of protein‐tyrosine phosphorylation in the signal transduction of platelet activating factor (PAF) was investigated in rabbit platelets with a range of synthetic compounds that inhibit protein‐tyrosine kinases. In particular, erbstatin (IC50~20) abrogated a wide range of platelet responses to PAF, including tyrosine phosphorylation of cellular proteins, polyphosphoinositide turnover, activation of membranous protein kinase C, platelet aggregation, and serotonin secretion. With about a third of the potency of erbstatin, compound RG50864 also inhibited many of these responses, whereas at 100 , genistein, 670C88 and ST271 were without effect. Finally, the ability of thrombin to cause platelet aggregation and serotonin secretion was also compromised by erbstatin.
Codon reading properties of an unmodified transfer RNA
Authors: Claesson Catharina , Samuelsson Tore , Lustig Florentyna , Borén Thomas
Published: July 2002

We have previously shown that the Mycoplasma mycoides glycine tRNA (anticodon UCC) effectively reads the codons GGU and GGC in violation of the classic codon reading rules. We have attempted to elucidate what structural elements in this tRNA molecule confer this translational property and in the course of this investigation T7 RNA polymerase transcription of the corresponding gene was used to produce a tRNA devoid of modified nucleosides. Using an in vitro translation system the ability of this tRNA to read the 4 glycine codons (GGU, GGC, GGA and GGG) was tested and it was shown to be as efficient as its normal, fully modified counterpart in the reading of all four codons. This result demonstrates that a tRNA devoid of modified nucleosides is able to efficiently sustain protein synthesis in vitro and, furthermore, that the normal modification pattern of the Mycoplasma glycine tRNA is not essential for the ability of this tRNA to read the glycine codons GGU and GGC effectively.
Bacillussubtilis holo‐cytochrome c‐550 can be synthesised in aerobic Escherichia coli
Authors: von Wachenfeldt Claes , Hederstedt Lars
Published: July 2002

Bacillus subtilis membrane‐bound holo‐cytochrome c‐550 was found to be expressed from the structural gene cloned on a plasmid vector in aerobically grown Escherichia coli and exhibited normal biochemical properties. This occurs despite the lack of endogenous eytochrome c and suggests that eytochrome c‐heme lyase activity is also present in aerobic E. coli. The membrane topology of B. subtilis eytochrome c‐550 was studied using fusions to alkaline phosphatase (PhoA). The results show that the heme domain (at least when fused to PhoA) can be translocated as apo‐cytochrome and confirm that the N‐terminal part of the cytochrome functions as both export signal and membrane anchor for the C‐tenninal heme domain. A model for the organisation of B. subtilis cytochrome c‐550 in the cytoplasmic membrane is presented.
Membrane depolarization inhibits thrombin‐induced calcium influx and aggregation in human platelets
Authors: Kovács Tünde , Tordai A. , Szász Ilma , Sarkadi B. , Gárdos G.
Published: July 2002

The relationship between thrombin‐evoked changes in intracellular calcium concentration ([Ca2+]i) and aggregation was examined in Indo‐1‐loaded human platelets. The stimulus‐induced intracellular calcium release and external calcium influx, as well as platelet aggregation, were studied in the same cell preparation. A close correlation between the sustained high [Ca2+]i level, depending on calcium entry, and the aggregation response was found. Gramicidin, at a concentration high enough to induce membrane depolarization, strongly inhibited the calcium influx and aggregation, but did not influence the thrombin‐induced intracellular calcium release. We conclude that calcium influx through depolarization‐inhibited calcium channels is a prerequisite of thrombin‐induced platelet aggregation.
Oxidized low density lipoprotein inhibits bradykinin‐induced phosphoinositide hydrolysis in cultured bovine aortic endothelial cells
Authors: Hirata Ken-ichi , Akita Hozuka , Yokoyama Mitsuhiro
Published: July 2002

Vascular endothelial cells, in response to various neurohumoral and physical stimuli, produce an endothelium‐derived relaxing factor, a substance which regulates vascular tone. We have demonstrated that oxidized low density lipoprotein (LDL) inhibits endothelium‐dependent relaxation. We studied the effect of oxidized LDL on inositol phosphates formation stimulated with bradykinin (BK) in cultured bovine aortic endothelial cells. BK elicited a rapid generation of inositol phosphates from inositol phospholipids. Accumulation of inositol 1,4,5‐trisphosphate (IP3) stimulated with BK (0.1 μM) was markedly inhibited by oxidized LDL. However, native LDL had little effect on BK‐induced accumulation of IP3. From these results, oxidized LDL inhibits receptor‐mediated phosphoinositides hydrolysis and modulates the endothelial function.
The spin trap, α‐phenyl N‐tert‐butylnitrone, inhibits the oxidative modification of low density lipoprotein
Authors: Kalyanaraman B. , Joseph Joy , Parthasarathy Sampath
Published: July 2002

The lipophilic spin trap, N‐tert‐butylnitrone (PBN) inhibits the formation of the oxidatively‐modified low density lipoprotein (LDL) by endothelial cells and by cupric ions. The LDL incubated in the presence of PBN with cells or cupric ions wax less readily degraded by macrophages than the LDL incubated in the absence of PBN. A lipid‐derived radical formed during oxidation of LDL was detected by spin trapping with PBN. It is likely that PBN inhibits the oxidative and biological modification of LDL by scavenging the LDL‐lipid‐derived radical.
Cadmium directly acts on endothelin receptor and inhibits endothelin binding activity
Authors: Wada Kenji , Fujii Yukako , Watanabe Hiroshi , Satoh Misako , Furuichi Yasuhiro
Published: July 2002

The binding of endothelin (ET) to human placenta ET receptor was strongly inhibited by cadmium ions (Cd2+) (IC50 = 2 × 10−5 M). Experiments with affinity cross‐linking showed that the major 40 kDa receptor was inhibited to form a [125I]ET‐1/receptor complex. The mode of inhibition was noncompetitive with respect to ET‐1. The inhibitory effect of Cd2+ on solubilized ET receptor was partially reversed by the chelating agent, ethylenediaminetetraacetic acid (EDTA), whereas the effect was irreversible for the membrane‐associated receptor. The rat aorta contractions by ET were prevented by pretreatment or addition of Cd2+.
Cysteinyl‐tRNA synthetase is a direct descendant of the first aminoacyl‐tRNA synthetase
Authors: Avalos Javier , Corrochano Luis M. , Brenner Sydney
Published: July 2002

The gene encoding the cysteinyl‐tRNA synthetase of E. coli was cloned from an E. coli genomic library made in λ2761, a lambda vector which can integrate and which carries a chloramphenicol resistance gene. A thermosensitive cysS mutant of E. coli was lysogenised and chloramphenicol‐resistant colonies able to grow at 42°C were selected to isolate phages containing the wild‐type cysS gene. The sequence of the gene was determined. It codes for a 461 amino‐acid protein and includes the sequences HIGH and KMSK known to be involved in the ATP and TRNA binding respectively of class I synthetases. The cysteinyl enzyme has segments in common with the cytoplasmic leucyl‐tRNA synthetase of Neurospora crassa, the tryptophanyl‐tRNA synthetase of Bacillus stearothermophilus, and the phenylalanyl‐tRNA synthetase of Saccharomyces cerevisiae. Sequence comparisons show that the amino end of the cysteinyl‐tRNA synthetase has similarities with prokaryotic elongation factors Tu; this region is close to the equivalent acceptor binding domain of the glutaminyl‐tRNa synthetase of E. coli. There is a further similarity with the seryl enzyme (a class II enzyme) which has led us to propose that both classes had a common origin and that this was the ancestor of the cysteinyl‐tRNA synthetase.