bluuebunny/crossref_metadata_2025 huggingface dataset:
De Symbolo Apostolorum. El caso del Retablo de Ánimas del Museo Catedralicio de Segorbe
Authors: Macián Ferrandis Julio
Published: February 2025

El Museo de la Catedral de Segorbe (Castellón), alberga un retablo de finales del siglo XV, adscrito al taller del maestro de Perea, dedicado a las almas del Purgatorio y en el que se representa el Juicio Final, la misa de san Gregorio y las penas del infierno. Los guardapolvos del conjunto albergan un apostolado con los artículos del Credo Romano. Sin embargo, estos puntos se encuentran desordenados, al mismo tiempo que faltan dos de ellos. En el presente trabajo se busca dar una respuesta a esta disposición del Símbolo, relacionándola con las diferentes escenas del retablo y sustentándolo en los comentarios al respecto de eminentes teólogos.
«Le dio un golpe con tanta furia y fuerça que fue milagro no matarle»: la agresión al escultor aragonés Juan Miguel Orliens en Zaragoza (1624)
Authors: Carretero Calvo Rebeca
Published: February 2025

Este artículo analiza el proceso inquisitorial incoado por el escultor oscense Juan Miguel Orliens en noviembre de 1624 en Zaragoza, en calidad de familiar del Santo Oficio, con motivo de la agresión que sufrió por parte del fustero Miguel Canales. Poco después de la reyerta, Orliens, el escultor aragonés más prestigioso del momento, decidió trasladarse a la ciudad de Valencia con toda su familia para comenzar una nueva etapa vital y, sobre todo, profesional.
Diversidad, cultura, nación: El currículum oculto de la Sociología de la Educación
Authors: García García Juan
Published: February 2025

El debate académico sobre la diversidad cultural en las aulas ha desatendido a menudo los factores estructurales y los marcos ideológicos en los que se inscriben los llamados planes o programas de educación intercultural. Ni siquiera la Sociología de la Educación, mucho más atenta que otras áreas de conocimiento al estudio del poder, la ideología y el currículum oculto en los procesos de enseñanza-aprendizaje, parece haber estudiado en profundidad la estrecha vinculación que la escuela habría tenido desde su nacimiento con la construcción del Estado y la naturalización de la nación. Ahora bien, ¿se puede reconocer la diversidad y fomentar la inclusión en las aulas sin tematizar el estudio de naciones y nacionalismo? ¿Se puede propiciar la interculturalidad del currículo sin deconstruir el nacionalismo curricular? En este trabajo se hace un balance crítico del abordaje y el tratamiento que la Sociología de la Educación ha venido realizando de la diversidad cultural, revisando para ello su presencia desigual durante cuatro décadas de congresos nacionales y su paulatina institucionalización temática en los manuales de Sociología de la Educación.
High resolution deep mutational scanning of the melanocortin-4 receptor enables target characterization for drug discovery
Authors: Howard Conor J , Abell Nathan S , Osuna Beatriz A , Jones Eric M , Chan Leon Y , Chan Henry , Artis Dean R , Asfaha Jonathan B , Bloom Joshua S , Cooper Aaron R , Liao Andrew , Mahdavi Eden , Mohammed Nabil , Su Alan L , Uribe Giselle A , Kosuri Sriram , Dickel Diane E , Lubock Nathan B
Published: February 2025

Deep Mutational Scanning (DMS) is an emerging method to systematically test the functional consequences of thousands of sequence changes to a protein target in a single experiment. Because of its utility in interpreting both human variant effects and protein structure-function relationships, it holds substantial promise to improve drug discovery and clinical development. However, applications in this domain require improved experimental and analytical methods. To address this need, we report novel DMS methods to precisely and quantitatively interrogate disease-relevant mechanisms, protein-ligand interactions, and assess predicted response to drug treatment. Using these methods, we performed a DMS of the melanocortin-4 receptor (MC4R), a G protein-coupled receptor (GPCR) implicated in obesity and an active target of drug development efforts. We assessed the effects of >6,600 single amino acid substitutions on MC4R’s function across 18 distinct experimental conditions, resulting in >20 million unique measurements. From this, we identified variants that have unique effects on MC4R-mediated Gα
s
- and Gα
q
-signaling pathways, which could be used to design drugs that selectively bias MC4R’s activity. We also identified pathogenic variants that are likely amenable to a corrector therapy. Finally, we functionally characterized structural relationships that distinguish the binding of peptide versus small molecule ligands, which could guide compound optimization. Collectively, these results demonstrate that DMS is a powerful method to empower drug discovery and development.
Sexual Failure Decreases Sweet Taste Perception in Male Drosophila via Dopaminergic Signaling
Authors: Wang Gaohang , Qi Wei , Huang Rui , Wang Liming
Published: February 2025

Sweet taste perception, a critical aspect of the initiation of feeding behavior, is primarily regulated by an animal’s internal metabolic state. However, non-metabolic factors, such as motivational and emotional states, can also influence peripheral sensory processing and hence feeding behavior. While mating experience is known to induce motivational and emotional changes, its broader impact on other innate behaviors such as feeding remains largely uncharacterized. In this study, we demonstrated that mating failure of male fruit flies suppressed sweet taste perception via dopamine signaling in specific neural circuitry. Upon repetitive failure in courtship, male flies exhibited a sustained yet reversible decline of sweet taste perception, as measured by the proboscis extension reflex (PER) towards sweet tastants as well as the neuronal activity of sweet-sensing Gr5a
+
neurons in the proboscis. Mechanistically, we identified a small group of dopaminergic neurons projecting to the subesophageal zone (SEZ) and innervating with Gr5a
+
neurons as the key modulator. Repetitive sexual failure decreased the activity of these dopaminergic neurons and in turn suppressed Gr5a
+
neurons via Dop1R1 and Dop2R receptors. Our findings revealed a critical role for dopaminergic signaling in integrating reproductive experience with appetitive sensory processing, providing new insights into the complex interactions between different innate behaviors and the role of brain’s reward systems in regulating internal motivational and emotional states.
Legalized Inequalities: Immigration and Race in the Low-Wage Workplace
Authors: Griffith Kati , Gleeson Shannon , Dubuisson Darlène , Campos-Medina Patricia
Published: February 2025

This book illuminates how government regulation (and under-regulation) degrades workplace conditions, as well as workers’ ability to contest them. The authors interpret government action and inaction broadly to include statutory frameworks, enforcement systems, and other implementation processes. They also include both punitive arms of governance and everyday mundane aspects of government bureaucracies. Through enacting, enforcing, administering, and interpreting laws, or by deciding not to do so, the government feeds poor working conditions and disempowers workers. The three parts of the book disaggregate and interrogate three key policy arenas through which this occurs: under-regulation of workers’ rights, an immigration regime that disempowers workers, and failure to counteract racialized labor hierarchies and colonial legacies. The book examines three domains successively, via three pairs of chapters that focus on how the government fuels precarious working conditions and shapes barriers and pathways to change. Throughout, the authors highlight instances where workers have resisted despite the odds—sometimes individually, sometimes collectively; sometimes quietly, sometimes loudly.
Comprehensive Evaluation of the Anti-hyperglycemic Efficacy of Tinospora cordifolia in Rodent Models Coupled with a Detailed Assessment of its Adverse Effect Profile
Authors: Ankhi Arjina Akter , Hasan Khandoker Shamim Al , Sultana Sanjida , Akhter Mehjabin , Trayee Sarani Pal , Nadvi Faisal Ahmed , Faruk Md. Omar
Published: February 2025

A prevalent endocrine condition, diabetes mellitus (DM) is generally characterized by diminished insulin function, which results in hyperglycemia and complications such as neuropathy and retinopathy. Bigunaides, sulfonylureas, thiazolidinediones (TZDs) and SGLT2 inhibitors are common oral antidiabetic drugs while each has unique adverse effects.  A medicinal herb called Tinospora cordifolia has the potential to control blood sugar levels by lowering oxidative stress and increasing insulin secretion. In the experimental rat model, diabetes was induced using alloxan. 50 rats were split up into ten groups for the study in order to examine how T. cardifolia extract affected blood glucose levels. Following alloxan-induced diabetes, the rats were given metformin, different dosages (such as 300mg, 600 mg and 900 mg) of T.cardifolia extract or plain water and food from day 7 to day 42. Elevated blood glucose, liver damage (increased SGPT/SGOT), kidney dysfunction (high creatinine/urea), and changed lipid profiles were all consequences of alloxan-induced diabetes. The therapeutic potential of the plant extract in managing diabetes and its complications is suggested by the significant reduction in blood glucose, improvement in liver and kidney markers, and correction of lipid imbalances, especially at medium (600mg) and high doses (900 mg).
Implementation of Indigenous Peoples Education (IPEd) in Lower Calanasan District, Philippines
Authors: Alday Maynard B.
Published: February 2025

Purpose: The study aimed to assess the implementation of the Indigenous People Education (IPEd) Program and its relationship to the learners’ scholastic achievement at the District of Lower Calanasan, Division of Apayao, school year 2021-2022.
Methods: The study looked into the personal profiles of the respondents in terms of age, sex, civil status, faculty rank, length of teaching service in years, and their highest educational attainment, These personal profiles of respondents will be tested through the Pearson r, if there’s a bearing with their perceptions on the level of implementation of the IPED Program along the seven indicators namely: Pedagogy and Methodology, Indigenous Knowledge Systems, Curriculum Content and Planning, Language of Instruction, Teacher Training, Instructional Materials, and Assessment and Evaluation. The null hypothesis was either rejected or accepted at .05 level of significance.
Results: The study found out that majority of the teachers in Lower Calanasan, Apayao are female whose age is in their mid-30s. The majority of the teachers are married who hold a Bachelor’s Degree with a Teacher I position. The said teachers have an average year of experience in teaching for over 10 years as of writing.
Digging deeper to the Level of Implementation of IPED, the teachers indicated that they were able to implement the Pedagogy and Methodology, Indigenous Knowledge Systems, Teacher training, Instructional materials, and the Assessment and Evaluation to a “great extent”.
Meanwhile, only Language of Instruction and Curriculum Content and Planning tallied a descriptive value of “to a very great extent”. In terms of the best practices of the teachers in implementing the IPED Program, the teachers indicated the strategy on “Translating modules of K to 12 into the Isnag dialect to make a more contextualized lesson”. When it comes to perceiving the benefits of the IPED Program, the teachers strongly agree that the said program, has a significant effect on the learners. Specifically, the study found out that the IPED program is helpful in making the IP learners have become active in class activities.
On the other hand, the students were found out to have achieved a very satisfactory mark in their core subjects during the School year 2021-2022. However, it can be noticed that the marks of the students are near the demarcation of the Satisfactory range.
Conclusions: Finally, the study found out that the level of implementation of the IPED Program particularly the indicators such as Pedagogy and Methodology; and Curriculum Content and Planning are both significantly related to the learners’ level of performance in their core subjects.
Mediating Effect of Work Environment on the Relationship between Locus of Control, learning Goal Orientation and Training Transfer of Genz Employees of Start-Up Companies in Jakarta
Authors: Tari Audria Cahya , Jimad Habibullah , Ribhan
Published: February 2025

This research aims to determine the influence of locus of control, learning goal orientation and work environment on training transfer of GenZ employees with self-efficacy as a mediating variable, the sample in this study was 210 Gen Z respondents in Start-Up Companies in Jakarta. This research used SEM-Amos analysis, the results of this research positive and significant locus of control, positive learning goal orientation and work environment characteristics and training transfer. Self efficacy mediates locus of control goal orientation and work environment characteristics and training transfer. It is recommended that Gen Z in start-up companies must be able to solve problems, build their own potential, personal skills, be able to complete difficult tasks and gain new experiences, teach each other among co-workers.
Mortality Predictors during Extrapulmonary Tuberculosis in Adults in the Infectious and Tropical Diseases Departments of Fann National University Hospital and Hôpital Principal de Dakar, Senegal
Authors: Mbaye Khardiata Diallo , Fall Ndeye Maguette , Massaly Aminata , Cisse Viviane Marie Pierre , Ndiaye Sokhna Waalo Mbacké , Diop Moustapha Ndiandam , Lakhe Ndeye Aissatou , Ka Daye , Badiane Aboubacr Sidikh , Diouf Assane , Ndour Cheikh Tidiane , Seydi Moussa
Published: February 2025

Introduction: Pulmonary tuberculosis remains the priority of national disease control programs, while extra-pulmonary cases are increasingly observed, often at a late stage. Additionally, in sub-Saharan Africa, data on these extra-pulmonary locations are scarce.
Methodology: This is a prospective, multicenter, descriptive, and analytical study including patients followed for extra-pulmonary tuberculosis in the Infectious and Tropical Diseases Departments of Fann National University Hospital and Hôpital Principal de Dakar, from March 1, 2019, to February 29, 2020. Data were entered into Epi Info™ version 7.2.2.6, exported to Excel, and processed using R software version 3.4.1.
Results: Overall, 189 patients were included. The mean age was 39 ± 16 years with a male predominance at 65.6%, representing a sex ratio of 1.9. Regarding medical history, a previous tuberculosis contact was found in 44 patients (23.3%) and a history of tuberculosis in 15 patients (7.9%). HIV infection was the most representative comorbidity in 34.4% of patients, followed by hypertension (7.9%) and diabetes (3.7%). Lymph node tuberculosis was the most frequent (54%), followed by neurological (26.2%), pleural (18.5%), and peritoneal (13.8%) locations in patients living with HIV, while in HIV-negative patients, pleural, peritoneal, and vertebral locations were more frequent than neurological involvement. The case fatality rate was 10.1%. Factors associated with death were age over 60 years: aOR: 1.07 (95% CI: 1.02–1.11), neurological location of tuberculosis: aOR: 7.05 (95% CI: 1.87–26.59), and anemia with hemoglobin level < 10 g/dl: aOR: 7.87 (95% CI: 1.62–38.1).
Conclusion: Tuberculosis remains a public health concern in resource-limited countries. In our series, young adult males were the most affected. Lymph node involvement was the most frequent location, followed by neurological and pleural and peritoneal serous involvement. More than a third of patients were co-infected with HIV, and factors associated with death were age over 60 years, neurological location, and the presence of anemia. Proper management of these factors could improve patient care.
Correlation and Regression Analysis of Growth and Yield Parameters in Jasmine (Jasminum sambac L.) during the Off-season
Authors: Kumaravel R. , Ganesh S.
Published: February 2025

The present investigation was attempted to highlight the correlation and regression Analysis of Growth and Yield Parameters in Jasmine (Jasminum sambac L.) During the Off-Season. Jasmine (Jasminum sambac L.) stands first among the fragrant loose flowers. India is one of the centre of origin of jasmine. In the present investigation, staggered pruning has been carried out to enhance the flower yield during off-season period (December to March). Data on various growth and yield component variables (X1–X­12) were subjected to correlation coefficient with flower yield (Y) and concrete content (Y). The results showed that the number of flowers per plant had the highest and positive association with flower yield (r=0.828**). The positive and significant “b” coefficient was also observed with (b=0.367**) growth and yield attributes. Hence, the regression equation to predict the flower yield would be Y= a + 0.367**. The leaf area was found to be highly correlated with concrete content (r=0.856**); whereas the regression coefficient is 0.895**. with one per cent significant. Therefore, the regression equation would be Y= a + 0.895x. Hence, it could be concluded from the present investigation that leaf area and number of flowers per plant are the important parameters to increase the flower yield and concrete content respectively.
Short - Term Solar Radiation Forecasting for Adaptive Solar Cell Using a Hybrid D-FFNN Model
Authors: Kusuma Hikmat Oka , Kartini Unit Three , Suprianto Bambang , Firmansyah Rifqi
Published: February 2025

Variations in the value of solar radiation affect the efficiency of solar panels and thus cannot be predicted. This causes instability in the generated power and negatively impacts the reliability of the solar power plant. This research formulates the prediction of solar radiation at short time intervals based on decomposition techniques and Artificial Neural Network - Feed Forward Multi-Layer Perceptron. The prediction method consists of the following steps: data pre-processing, application of the modified FFN model, and evaluation through RMSE, MSE, MAPE, and MAE. The experimental results show that the prediction model performs well, with MAE of 3.3823, MSE of 37.0858, RMSE of 6.089, and MAPE of 0.29%. Although there is variation between the predicted and actual values, the overall trend of the data yields good accuracy, with a deviation of only 5%. This shows that the combination of decomposition and FFNN techniques can improve the prediction accuracy of solar radiation which is crucial for adaptive solar panel system applications. The next research direction is to build more complicated models using larger data shares and other decomposition methods, which will improve the prediction accuracy under rapidly changing weather conditions.
Advanced Data Analytics for Real-Time Performance Engineering
Authors: Ramdoss Vasudevan Senathi
Published: February 2025

Real-time data analytics plays a crucial role in performance engineering by enabling continuous monitoring and analysis of system performance metrics as they occur. This allows engineers to identify bottlenecks, pinpoint performance issues, and make proactive adjustments in real-time, ultimately leading to optimized system performance and improved user experience. This paper explores the key aspects, applications, and technological considerations of real-time data analytics in performance engineering, along with its benefits and industry use cases.
The role of citric acid in intermediate metabolism in animal tissues
Authors: Krebs H.A. , Johnson W.A.
Published: July 2002

In the present paper experiments are reported which throw new light on the problem of the intermediate stages of oxidation of carbohydrate; in conjunction with the work of Szent‐Györgyi
20), Stare and Baumann
19) and Martius and Knoop
13,14) the new experiments allow us to outline the principal steps of the oxidation of sugar in animal tissues.
Short‐term disappearance of muscarinic cell surface receptors in carbachol‐induced desensitization
Authors: Maloteaux Jean-M. , Gossuin Annie , Pauwels Petrus J. , Laduron Pierre M.
Published: July 2002

A rapid carbachol‐induced disappearance of muscarinic cell surface receptors was shown using [3H]methyl scopolamine as ligand on intact 108CC15 hybrid cells or rat cerebellar cells. This phenomenon is temperature‐dependent, correlated to agonist stimulation and reversible. In these short time periods (⩽30 min), no change was observed in the total receptor amount measured on membrane preparations. This disappearance of cell surface receptors could represent the first event in cell desensitization which could be followed by receptor recycling in physiological conditions or by receptor degradation if the stimulation by agonists persists, as in long‐term regulation.
NMR solution spatial structure of ‘short’ scorpion insectotoxin I5A
Authors: Arseniev Alexander S. , Kondakov Vladimir I. , Maiorov Vladimir N. , Bystrov Vladimir F.
Published: July 2002

Two‐dimensional 500 MHz NMR study reveals the three‐dimensional structure of the insectotoxin I5A of Buthus eupeus in aqueous solution. The most likely set of disulfide linkages is proposed. Comparison with the single crystal structure of the ‘long’ toxin v‐3 of Centruroides sculpturatus shows similarity in their α‐helical and antiparallel β‐structure fragments.
A fast method of comparing protein structures
Authors: Murthy M.R.N.
Published: July 2002

Comparative studies on protein structures form an integral part of protein crystallography. Here, a fast method of comparing protein structures is presented. Protein structures are represented as a set of secondary structural elements. The method also provides information regarding preferred packing arrangements and evolutionary dynamics of secondary structural elements. This information is not easily obtained from previous methods. In contrast to those methods, the present one can be used only for proteins with some secondary structure. The method is illustrated with globin folds, cytochromes and dehydrogenases as examples.
Time‐course and stoichiometry of light‐induced proton release and uptake during the photocycle of bacteriorhodopsin
Authors: Grzesiek Stephan , Dencher Norbert A.
Published: July 2002

The kinetics and stoichiometry of light‐induced proton release in purple membrane suspensions have been investigated using the pH‐indicator dye pyranine and single‐turnover flash spectroscopy at a time resolution of 0.1 μs. The number of protons detected by pyranine is inversely proportional to the buffering power of the medium and 1.1 ± 0.2 protons are released per photocycling bacteriorhodopsin molecule (pH 7.0, 20°C). At high ionic strength (250 mM KCl) and higher phosphate buffer concentrations (1 mM) the proton release lags slightly behind the formation of the intermediate M‐412 and proton reuptake by the purple membrane parallels the slow decay process of M‐412 or the decay of O‐640.
Transport of F1‐ATPase subunit β into mitochondria depends on both a membrane potential and nucleoside triphosphates
Authors: Pfanner Nikolaus , Neupert Walter
Published: July 2002

Transport of cytoplasmically synthesized precursor proteins into or across the inner mitochondrial membrane requires a mitochondrial membrane potential. We have studied whether additional energy sources are also necessary for protein translocation. Reticulocyte lysate (containing radiolabelled precursor proteins) and mitochondria were depleted of ATP by pre‐incubation with apyrase. A membrane potential was then established by the addition of substrates of the electron transport chain. Oligomycin was included to prevent dissipation of Δψ by the action of the F0F1‐ATPase. Under these conditions, import of subunit β of F1‐ATPase (F1β) was inhibited. Addition of ATP or GTP restored import. When the membrane potential was destroyed, however, the import of F1β was completely inhibited even in the presence of ATP. We therefore conclude that the import of F1β depends on both nucleoside triphosphates and a membrane potential.
Isolation and characterization of a lectin with exclusive specificity towards mannose from snowdrop (Galanthus nivalis) bulbs
Authors: Van Damme Els J.M. , Allen Anthony K. , Peumans Willy J.
Published: July 2002

A lectin was isolated from snowdrop (Galanthus nivalis) bulbs by affinity chromatography on mannoseagarose. It is a tetrameric protein composed of 4 identical subunits of 13 kDa which are not held together by disulphide bridges. The G. nivalis agglutinin exhibits exclusive specificity towards mannose. Although it readily agglutinates rabbit erythrocytes it is completely inactive with human red blood cells.
Interaction of iodinated vinculin, metavinculin and α‐actinin with cytoskeletal proteins
Authors: Belkin A.M. , Koteliansky V.E.
Published: July 2002

Iodinated vinculin, metavinculin and α‐actinin were used to probe the interaction of these proteins with electrophoretically separated cytoskeletal proteins. Using the gel overlay technique, we detected strong binding of 125I‐vinculin and 125I‐metavinculin to α‐actinin, 175 kDa polypeptide, talin, vinculin and metavinculin themselves, and moderate binding to actin.125I‐α‐actinin was capable of interacting with vinculin and metavinculin. The specific binding of 125‐I‐α‐actinin to vinculin and metavinculin immobilized on a polysterene surface was also demonstrated. We suggest that the ability of vinculin and α‐actinin to form a complex may be realized in microfilament‐membrane linkages.
Prediction of terminal protein and ribonuclease H domains in the gene P product of hepadnaviruses
Authors: Khudyakov Yu.E. , Makhov A.M.
Published: July 2002

By means of comparative analysis of primary and secondary structures, and hydropathy plots of hepadnavirus P proteins new functional domains were revealed additionally to the polymerase domain which had been found earlier in these proteins. The C‐terminal part of P proteins was revealed to be significantly similar to ribonuclease H of E. coli. The ribonuclease H functional domain is known to be an integral entity of retrovirus reverse transcriptase as a rule. Availability of this domain indicates once more the putative reverse transcriptase properties of the P products. The proteins of hepadnaviruses were compared to terminal proteins of picornaviruses, adenoviruses and bacteriophages. The data obtained suggested that a conservative N‐terminal region of P proteins functions as protein primer for DNA synthesis in hepadnaviruses.
Oxyradical reactions: from bond‐dissociation energies to reduction potentials
Authors: Koppenol W.H.
Published: July 2002

Destructive radical reactions involve alkykl, alkoxyl and alkylperoxyl radicals, as well as alkylhydroperoxides. From bond energies the following reduction potentials vs NHE at neutral pH are derived: Esuo'(RO./ROH) = 1.6 V, E
o'(ROO./ROOH) = 1.0 V, E
o'(ROOH/RO., H2;0) = 1.9 V, and the two‐electron reduction potential E
o'(ROOH/ROH, H2O) = 1.7 V. Hydrogen abstraction from a bis‐allylic methylene group by alkoxyl and alkylperoxyl radicals is favourable with Gibbs energies of −23 and −9 , respectively. Similarly, alkoxyl radicals can oxidize alkylhydroperoxides, ΔGo' = −14 .
Selective blockade of NMDA‐activated channel currents may be implicated in learning deficits caused by lead
Authors: Alkondon Manickavasagom , Costa Alberto C.S. , Radhakrishnan Veeraswamy , Aronstam Robert S. , Albuquerque Edson X.
Published: July 2002

The effect of Pb2+ on glutamate receptor activity in rat hippocampal neurons was investigated with a view of explaining the cognitive and learning deficits produced by this heavy metal. Pb2+ (2.5–50 μ;M) selectively inhibited N‐methyl‐D‐aspartate (NMDA)‐induced whole‐cell and single‐channel currents in a concentration‐dependent but voltage‐independent manner, without significantly altering currents induced by either quisqualate or kainate. The frequency of NMDA‐induced channel activation was decreased by Pb2+. Neither glycine (10–100 μ;M), nor Ca2+ (10 mM) reversed the effect of Pb2+. Pb2+ also inhibited the [3H]MK‐801 binding to rat hippocampal membranes in vitro. The elucidation of the actions of Pb2+ on the NMDA receptor ion channel complex provides important insights into the clinical and toxic effects of this cation.
Molecular cloning of human cardiac troponin I using polymerase chain reaction
Authors: Vallins William J. , Brand Nigel J. , Dabhade Nina , Butler-Browne Gillian , Yacoub Magdi H. , Barton Paul J.R.
Published: July 2002

We have used the polymerase chain reaction (PCR) to synthesise a cDNA encoding part of human cardiac troponin I. Amplification was achieved using fully degenerate sets of oligonucleotides corresponding to conserved regions of amino acid sequence identified in other troponin I isoforms. The cloned PCR fragment was subsequently used to isolate full‐length cDNAs from a cardiac cDNA library. We describe the approach, as a general cloning strategy starting from limited amino‐acid sequence data and report the cloning, and complete amino acid sequence of human cardiac troponin I. Analysis of human development using these clones demonstrates early expression of this gene in the heart.
An organophosphorus compound, Vx, selectively inhibits the rat cardiac Na+,K+‐ATPase α1 isoform Biochemical basis of the cardiotoxicity of Vx
Authors: Robineau Pascale , Leclercq Yves , Gerbi Alain , Berrebi-Bertrand Isabelle , Lelievre Lionel G.
Published: July 2002

Serine‐specific reagents, anticholinesterase organophosphorus compounds like Vx provoke, in the micromolar range, digitalis‐like ventricular arrythmias of non‐cholinergic origin in rodent hearts. The sensitivities of the two rat cardiac Na+,K+‐ATPase isoforms (α1 and α2) to Vx (0.1–100 μM) were measured in sarcolemma vesicles. At 1 μM Vx, the inhibition of the total activity averaged 18% but never exceeded 75% with 100 μM. When the α2 isoform activity was inhibited by 0.1 μM ouabain, α1 was 35% inhibited by 1 μM Vx, i.e. a 16±4% inhibition of the total acitivity. The cardiac α1 being related to the digitalis‐induced toxicity, its selective inhibition by a micromolar dose of Vx fully accounts for the cardiotoxicity of Vx. Inasmuch as Vx had no effect on the rat kidney α1, differentially inactivated the cardiac isozymes and specifically reacted with serine residues, the putative binding‐site(s) of the organophosphorus compound on the Na+,K+‐ATPase molecules has been considered.
Interference with protein binding at AP2 sites by sequence‐specific methylation in the late E2A promoter of adenovirus type 2 DNA
Authors: Hermann Ralf , Doerfler Walter
Published: July 2002

The in vitro methylation of the +6, +24, and −215 located 5′‐CCGG‐3′ sequences in the late E2A promoter of adenovirus type 2 (Ad2) DNA abrogates promoter function. 3‐Methyldeoxycytidine (5‐mC) at positions +6 and +24 in both or either of the two DNA complements in the late E2A promoter abolishes the formation of high‐molecular‐mass DNA‐protein complex that is essential for promoter function. The formation of this complex can be competed for by an oligodeoxyribonucleotide with a consensus AP2 sequence, but not by AP1, AP3, and CREB sequences, The AP2 sites comprise the +6 and +24 located 5′‐CCGG‐3′ sequences in the late E2A promoter; the AP1, AP3, and CREB sequences are in their immediate vicinity, Methylation of either the +6 or the +24 5′‐CCGG‐3′ sequence also compromises formation of the DNA‐protein complex. A 40 nucleotide pair oligodeoxyribonucleotide encompassing the −215 5′‐CCGG‐3′ site in the late E2A promoter can also form DNA‐protein complexes which is not affected by the introduction of a 5‐mC residue in the −215 position. The data suggest that the AP2 protein together with other proteins is involved in the generation of a transcription‐activating complex with the late E2A promoter of Ad2 DNA, and the formation of this complex is completely abolished when both the +6 and +24 5′‐CCGG‐3′ sequences are methylated.
Structural symmetry of the extracellular domain of the Cytokine/Growth hormone/Prolactin receptor family and Interferon receptors revealed by Hydrophobic Cluster Analysis
Authors: Thoreau E. , Petridou B. , Kelly P.A. , Djiane J. , Mornon J.P.
Published: July 2002

Sequence comparison based on Hydrophobic Cluster Analysis procedures shows that the extracellular ≈ 200 amino acids domains of cytokines receptors belonging to the Cytokine/Growth hormone/Prolactin receptor family and to the Interferon one are organized in two homologous subdomains. Further, comparison of the subdomains of 32 independent sequences and of a lot of already recognized homologous domains with data bases could lead to the hypothesis that these ≈ 100 amino acids subdomains could possess the overall fold of the constant immunoglobulin domains and so could belong to the immunoglobulin superfamily.
Activation of Epstein‐Barr virus promoters by a growth‐factor and a glucocorticoid
Authors: Schuster C. , Chasserot-Golaz S. , Beck G.
Published: July 2002

Transforming growth factor‐β (TGF‐β) and a glucocorticosteroid, Dexamethasone (DXM), both cause transcriptional induction of Epstein‐Barr virus (EBV) early antigens (EA) in Daudi lymphoma cells. The viral induction occurs through the viral promoter DR overlapping an origin of replication which is active during the lytic cycle. Each hormone requires specific regions on the DR promoter. Since these regions also mediate the action of two viral transcription factors, EBI and R, it may be emphasized that EBI and/or R are involved in the EA induction process by TGF‐β and by DXM.
Inhibition of neutrophil superoxide production by human plasma α1‐antitrypsin
Authors: Bucurenci Nadia , Blake David R. , Chidwick Keith , Winyard Paul G.
Published: July 2002

We report here that human plasma α1‐antitrypsin (α1‐AT) inhibited human neutrophil O2
− release elicited by a variety of stimulants. In comparison, the inhibitory capacities of two serine protease inhibitors, l‐1‐tosylamide 2‐phenylethylchloromethyl ketone (TPCK) and soybean trypsin inhibitor (SBTI) and the human recombinant α1‐AT mutant, α1‐AT‐Arg358 were in the order: α1‐AT ‐ TPCK> α1‐AT‐Arg358 > SBTI when cells were stimulated with concanavalin A plus cytochalasin E. These data suggest that, in human inflammatory fluks containing relatively high concentrations of α1‐AT (such as rheumatoid arthritis synovial fluids) (i) α1‐AT may down‐regulate the inflammatory process by inhibiting the neurophil respiratory burst and (ii) serpin oxidation by neutrophil‐released oxygen species is unlikely to occur.
RNase H activity of HIV reverse transcriptases is confined exclusively to the dimeric forms
Authors: Restle T. , Müller B. , Goody R.S.
Published: July 2002

A method for the rapid preparation of a defined substrate to monitor RNase H activity has been developed. Using this substrate, we have investigated the RNase H activities of the different forms of recombinant HIV‐1 and HIV‐2 reverse, transcriptase (RT) in detail. As we report here, RNase H activity is associated only with the dimeric forms (p51/p66 or p66/p66) of the enzymes
Shortened cecropin A‐melittin hybrids Significant size reduction retains potent antibiotic activity
Authors: Andreu David , Ubach Josep , Boman Anita , Wåhlin Birgitta , Wade David , Merrifield R.B. , Boman Hans G.
Published: July 2002

We have earlier reported two 26‐residue antibacterial peptides made up from different segments ol'cecropin A (CA) and melittin (M). We now report a substantial reduction in size at the C‐terminal section of the highly active hybrid CA(1–8)M(1–18), leading to a series of 20‐, 18‐ and 15‐residue analogs with antibiotic properties similar to the larger molecule. In particular, the 15‐residue hybrids CA(1–7)M(2–9), CA(1–7)M(4–11) and CA(1–7)M(5–12) are the shortest cecropin‐based peptide antibiotics described so far, with antibacterial activity and spectra similar or better than cecropin A and a 60% reduction in size. Their reduced size and highly α‐helical structure require an alternative mechanism for their interaction with bacterial membranes.
The WD‐40 repeat
Authors: van der Voorn Loesje , Ploegh Hidde L.
Published: July 2002

An amino acid sequence motif, called the WD‐40 repeat, has been found as a repeat in a large variety of proteins that do not share any obvious functional properties. At present, the function of the repeated motif is not known for any of these proteins. Interestingly, recent experiments in yeast indicate that several proteins containing the WD‐40 repeat are genetically associated with members of the TPR‐family, a protein family that is characterized by the presence of another repeated motif of unknown function: the tetratricopeptide repeat. It is conceivable that proteins containing the WD‐40 repeat interact physically with members of the TPR‐family via their respective repeated motifs.
Molecular cloning of a cDNA that encodes a serine protease with chymotryptic and collagenolytic activities in the hepatopancreas of the shrimp Penaeus vanameii (Crustacea, Decapoda)
Authors: Sellos Daniel , Van Wormhoudt Alain
Published: July 2002

Two clones were isolated by screening a shrimp hepatopancreas cDNA library with a DNA fragment obtained by PCR amplification using two oligonucleotides based on the partial protein sequence of Penaeus vanamei chymotrypsin purified earlier. One of these clones, PVC 7 contains a complete cDNA coding for a serine protease. The deduced amino acid sequence shows the existence of a 270 residue‐long preproenzyme containing a highly hydrophobic signal peptide of 14 amino acids. This suggests the existence of a putative zymogen form of the enzyme containing a 30 amino acid‐long peptide which is cleaved to give a mature protein of 226 residues. A highly preferred codon usage is observed for this protein. The other obtained cDNA was found to encode the less predominant variant of the protein. Sequence alignments show that shrimp chymotrypsin is highly homologous with crab collagenase (77% homology taking into account the same amino acid at the same position, and 83% homology taking into account amino acids wall conserved function) and that it is more similar to mouse trypsin (41% homology of strictly conserved amino acids) than to hornet chymotrypsin (35% homology).
Dopaminergic stimulation up‐regulates the in vivo expression of brain‐derived neurotrophic factor (BDNF) in the striatum
Authors: Okazawa Hitoshi , Murata Miho , Watanabe Masahiko , Kamei Masaki , Kanazawa Ichiro
Published: July 2002

We investigated the effect of dopamine on the in vivo expression of brain‐derived neurotrophic factor (BDNF) in the striatum of mouse. BDNF mRNA expression in the striation, which was Quantified with the reverse transcriptase polymerase chain reaction, was up‐repulated from 2 h after oral administration of levodopa, a precursor of dopamine. The increase was sustained for 16 h. Co‐administrstion of haloperidol partially inhibited dopamine‐induced BDNF enhancement. These data suggest that dopaminergic stimulation directly promotes the expression of BDNF in the striatum in vivo.
Caffeic acid phenethyl ester as a lipoxygenase inhibitor with antioxidant properties
Authors: Sud'ina G.F. , Mirzoeva O.K. , Pushkareva M.A. , Korshunova G.A. , Sumbatyan N.V. , Varfolomeev S.D.
Published: July 2002

Caffeic acid phenethyl ester, an active component of propolis extract, inhibits 5‐lipoxygenase in the micromolar concentration range. The inhibition is of an uncompetitive type, i.e. the inhibitor binds to the enzyme‐substrate complex but not to the free enzyme. Caffeic acid phenethyl ester also exhibits antioxidant properties. At a concentration of 10 μM, it completely blocks production of reactive oxygen species in human neutrophils and the xanthine/xanthine oxidase system.
Mutagenesis of human profilin locates its poly(l‐prolme)‐bindmg site to a hydrophobic patch of aromatic amino acids
Authors: Björkegren Camilla , Rozycki Mike , Schutt Clarence E. , Lindberg Uno , Karlsson Roger
Published: July 2002

The actin‐binding protein, profilin, contains a src‐homology (SH) 3‐like fold (Schutt C.E. et al., submitted), and its tight interaction with poly(l‐proline) is reminiscent of the binding activity exhibited by SH3‐domains. Here we demonstrate that replacements of aromatic amino acids in a hydrophobic patch on the surface of the profilin molecule abolish its poly(l‐proline)‐binding capacity. However, the location of this hydrophobic patch is found in another region of the molecule than that displaying structural similarities with SH3 domains.
Primary structures and expression from cDNAs of rat opioid receptor δ‐and μ‐subtypes
Authors: Fukuda Kazuhiko , Kato Shigehisa , Mori Kenjiro , Nishi Miyuki , Takeshima Hiroshi
Published: July 2002

The complete amino acid sequences of rat opioid receptors (designated as ROR‐A and ROR‐B) have been deduced by cloning and sequencing the cDNAs. The ligand‐binding properties of ROR‐A and ROR‐B expressed from the cloned cDNAs in Chinese hamster ovary cells correspond most closely to those of the pharmacologically defined δ‐ and μ‐opioid receptor subtypes, respectively. RNA blot hybridization analysis revealed that cerebrum and brainstem contain both ROR‐A and ROR‐B mRNAs, whereas neither ROR‐A nor ROR‐B mRNAs can be detected in cerebellum.
Protein kinase C inhibitors induce apoptosis in human malignant glioma cell lines
Authors: Couldwell William T. , Hinton David R. , He Shikun , Chen Thomas C. , Sebat Ibrahim , Weiss Martin H. , Law Ronald E.
Published: July 2002

Previous work has demonstrated the importance of the protein kinase C (PKC) system in regulating glioma growth, and has led to clinical trials utilizing PKC inhibitors as adjuncts in the therapy of patients harboring malignant gliomas. This study was performed to explore the possibility that inhibition of PKC in gliomas was triggering an apoptosis signal. Glioma cell lines were treated with PKC inhibitors staurosporine (10 nM), and tamoxifen (10 μM). DNA from cells treated with each of these drugs exhibited a ‘ladder’ pattern of oligonucleosome‐sized fragments characteristic of apoptosis, thus suggesting that in glioma cells, these drugs may be cytocidal in action.
Prothymosin α binds to histone H1 in vitro
Authors: Papamarcaki Thomais , Tsolas Orestes
Published: July 2002

Previous studies have shown that prothymosin α (Pro Tα) is a nuclear acidic protein implicated in cell proliferation. To identify proteins that interact with Pro Tα we have used ligand‐blotting assays. We report here that purified Pro Tα binds specifically to histone H1 in a dose dependent manner. Polyglutamic acid, an analog of the central acidic domain of Pro Tα, strongly inhibits the above interaction, suggesting that the binding of Pro Tα to histone H1 is mediated through its acidic domain.
Free insulin‐like growth factors (IGF‐I and IGF‐II) in human serum
Authors: Frystyk Jan , Skjærbæk Christian , Dinesen Bo , Ørskov Hans
Published: July 2002

Using ultrafiltration by centrifugation we have isolated the free, unbound fractions of insulin‐like growth factor I and II (free IGF‐I and IGF‐II) in human serum. In this way near in vivo conditions could be maintained before and during isolation. The recovery was 80 to 100% in the ultrafiltrates, which contained no detectable amounts of IGF‐binding proteins (IGFBPs) as measured by Western ligand blotting and IGFBP‐1 and IGFBP‐3 immunoassays. The concentration of free peptides was measured in two ultrasensitive non‐competitive IGF‐I and IGF‐II time‐resolved fluoroimmunoassays. We found that (i) equilibrium between free and protein‐complexed IGF was strongly dependent on re‐establishment of in vivo conditions (temperature, pH, ionic milieu and dilution); (ii) metabolic events (glucose load and fasting) caused significant changes in free IGF‐I and IGF‐II levels without concomitant changes in total circulating levels of IGFs; (iii) in 49 healthy adult subjects (20 to above 60 years) free IGF‐I was inversely related to age and ranged from 950 ± 150 ng/l (mean ± S.E.M.) (20–30 years) to 410 ± 70 ng/l (⪢ 60 years). The relative percentage was, however, unchanged, being 0.38 ± 0.02% of total IGF‐I. In contrast, free IGF‐II was independent of age, being 1,480 ± 80 ng/l (∼0.20 ± 0.01% of total IGF‐II).
The kinetics of the interaction between the actin‐binding domain of α‐actinin and F‐actin
Authors: Kuhlman Philip A. , Ellis Jacqueline , Critchley David R. , Bagshaw Clive R.
Published: July 2002

Measurement of the binding equilibrium for the interaction of α‐actinin with F‐actin is complicated by secondary reactions involving cross‐linking and/or bundling of the actin filaments. To quantitate the initial binding event, we studied the interaction of the bacterially expressed actin‐binding domain (ABD) of chick smooth muscle α‐actinin with F‐actin. Stopped‐flow measurements revealed a quench in protein fluorescence and an enhancement in light scattering when ABD binds to F‐actin yielding second order rate constants for association of 2 × 105, 1.8 × 106 and 4 × 106 M−1 · s−1 at 5°C, 15°C and 25°C, respectively. At the latter two temperatures the dissociation rate constants were 1.5 and 9.6 s−1, giving equilibrium constants of 0.83 and 2.4 μM, respectively. Optical changes on mixing intact α‐actinin with F‐actin were dominated by secondary bundling events.
Multiple functions of pro‐parts of aspartic proteinase zymogens
Authors: Koelsch Gerald , Mareš Michael , Metcalf Peter , Fusek Martin
Published: July 2002

The importance of aspartic proteinases in human pathophysiology continues to initiate extensive research. With burgeoning information on their biological functions and structures, the traditional view of the role of activation peptides of aspartic proteinases solely as inhibitors of the active site is changing. These peptide segments, or pro‐parts, are deemed important for correct folding, targeting, and control of the activation of aspartic proteinase zymogens. Consequently, the primary structures of pro‐parts reflect these functions. We discuss guidelines for formation of hypotheses derived from comparing the physiological function of aspartic proteinases and sequences of their pro‐parts.
Replacement of proteasome subunits X and Y by LMP7 and LMP2 induced by interferon‐γ for acquirement of the functional diversity responsible for antigen processing
Authors: Akiyama Kinya , Kagawa Susumu , Tamura Tomohiro , Shimbara Naoki , Takashina Makoto , Kristensen Poul , Hendil Klavs B. , Tanaka Keiji , Ichihara Akira
Published: July 2002

Proteasomes catalyze the non‐lysosomal, ATP‐dependent selective breakdown of ubiquitinated proteins and are thought to be responsible for MHC class I‐restricted antigen presentation. Recently, we reported that gamma interferon (IFN‐γ) induced not only marked synthesis of the MHC‐encoded proteasome subunits LMP2 and LMP7, but also almost complete loss of two unidentified proteasome subunits tentatively designated as X and Y in various human cells. Here, we show that subunit X is a new proteasomal subunit highly homologous to LMP7, and that subunit Y is identical to the LMP2‐related proteasomal subunit delta. Thus, IFN‐γ appears to induce subunit replacements of X and Y by LMP7 and LMP2, respectively, producing 'immuno‐proteasomes' with the functional diversity responsible for processing of endogenous antigens.
Shortened amoebapore analogs with enhanced antibacterial and cytolytic activity
Authors: Andrä Jörg , Berninghausen Otto , Wülfken Jan , Leippe Matthias
Published: July 2002

Amoebapores are cytolytic peptides of Entamoeba histolytica which function by the formation of ion channels in target cell membranes. Three isoforms (amoebapore A, B, and C) exist in amoebic cytoplasmic granules. They are composed of 77 amino acid residues arranged in four α‐helical domains. In order to analyze the structure‐function relationships, 15 synthetic peptides of 24–25 residues were constructed based on the assumption that the third helix is the membrane‐penetrating domain and on the previous finding that positively charged residues are significant for activity. Activity of these short versions of Amoebapores was determined towards artificial and natural targets, such as liposomes, bacteria, erythrocytes and a human tumor cell line. It was found that some of the novel peptides were highly active and showed a broader activity spectrum compared to the parent molecules.