bluuebunny/crossref_metadata_2025 huggingface dataset:
[Retracted] Indigenising Anthropology with Guattari and Deleuze by Barbara Glowczewski
Authors: Perez James
Published: February 2025

Anthropologist Barbara Glowczewski has been conducting fieldwork with indigenous people around the world, focusing largely on the Warlpiri of Australia, since the late 1970s. Indigenising Anthropology with Guattari and Deleuze is a collection of essays written by Glowczewski that spans over four decades. The French scholars Pierre-Felix Guattari and Gilles Deleuze are included in the title as Glowczewski was enrolled in seminars with the two men while conducting her early work at the University of Paris. Hence, the ideologies of these two French academics assist in informing the direction of the research. The fourteen essays by Glowczewski are organized into five different sections and follow a chronological trajectory beginning from the early 1980s to the late 2010s. This structure provides snapshots regarding different eras of anthropological research (how fieldwork was conducted and the different theoretical lenses through which people were viewed) and also speaks to how the Warlpiri have changed over time. The text, in its entirety, is currently relevant as grounded theory and postcolonialism are becoming more and more prevalent within many fields of academia. Ethnographic research is focusing more on creating theories from the data collected (rather than applying theories to data), allowing narratives to speak for themselves, and providing a way for once silent and minority voices to be heard in the traditional Western world. Hence, the assortment of essays by Glowczewski serves as a starting point to discuss where academic research has been, where it currently is, and gestures towards the possibilities of future work.
Positionality of Self in Writing and God Trick Fallacy
Authors: Morrison Aimée
Published: February 2025

I don’t write unless I get invited to. It’s not that I’m so important or famous or in demand. It’s that I tend to have a comically bad time getting through blind peer review, to the extent that it takes me years sometimes to get an article accepted. In at least one instance, I had a conference paper proposal rejected by a reviewer acting on behalf of the same program committee that, simultaneously and on the basis of the same research, had invited me to deliver the keynote address. An editor at a flagship new media journal very strongly pushed me, in the first piece I had written as a new professor, to take out all the things that had made the article fun for me to write, things that made it more readable, vivid, and effective. It was a paper about rhetoric and metaphor that was forbidden from employing rhetoric and metaphor to make its argument. The fate of the following sentence was the subject of a surprisingly long email chain: “Language may shift our view of the world, but a popular consensus on vocabulary and metaphor does not necessarily alter the material operation of that world: tucking a flower into a gun barrel creates a powerful visual symbol, but does not preclude the florist being shot” (Morrison 74). These editors, and others since, operationalize the idea that scholarly writing has a specific voice in which its arguments must be expressed, which seems to be much flatter, less spiky or silly,1 literal rather than figurative, impersonal, distinguished from my own style of writing by its formality and earnestness.
"Empathy and Abjection after Burke (1): On the Rise and Fall of “Listening-Rhetorics,” 1936–2023"
Authors: Baumlin James S.
Published: February 2025

What is it that leads rhetoric to succeed, or fail, as an instrument of persuasion? What is it in human psychology that makes individuals susceptible, or resistant, to rhetorical appeals? What are the moments and movements in recent history that have led theorists to revise their understanding of rhetoric in its aims and techniques? These questions underlie the two-part survey that follows. It was in 1950—at mid-20th century—that Kenneth Burke published his Rhetoric of Motives, whose agonistic model of discourse rested in a group psychology of identification bound to a social anthropology of scapegoating. Through subsequent decades, Western rhetorical theory has stayed in touch with Burkean concepts; methods as diverse as Rogerian argument, Corderian expressivism, and Booth’s “listening-rhetoric” took Burke’s identification as a precursor and starting point. Though their vocabularies diverged, each shared an audience psychology grounded in “empathetic understanding” (Rogers), seeking common ground between opposing factions and the possibility of mutual assent (Booth). For the authors surveyed here wrote in times of war—from World War II and the Cold War to Korea, Vietnam, Iraq, Afghanistan, Syria, and the post-9/11 “war on terror.” And each wrote in times of social-political unrest, with protests—often violent—raging across U.S. city streets and college campuses. Their collective aim was salutary: to reduce conflict, induce cooperation, and increase social cohesion. And yet, with each version of this “new” rhetoric, a criticism arises. Whereas a rhetoric of empathy seeks to overcome divisiveness, the Burkean model remains agonistic at its core: identification entails division, and vice versa. So, even as the “new” rhetoric evolved, an alternative was being articulated in fields of feminism, postcolonialism, and cultural studies generally: Theirs became a rhetoric, not of identification, but of cultural/bodily difference. Representing what was largely unassimilable in the voice of the subaltern “Other,” their critique of the rhetorics of “empathetic understanding” made these latter seem naïve.
O sentido de vida como caminho para espiritualidade
Authors: Aquino Thiago Antonio Avellar de , Cristino Ana Caroline Cabral , Patrício Ana Clara de Andrade
Published: February 2025

O presente estudo teve como objetivo investigar a produção científica brasileira acerca do sentido de vida como um caminho para a espiritualidade, utilizando a abordagem da logoterapia e análise existencial. Para tanto, a partir de uma revisão de literatura, foi realizada uma busca na base de dados da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), SciELO, Scopus, Web of Science e dos artigos das revistas elencadas pela Associação de Pós-graduação e Pesquisa em Teologia e Ciências da Religião (ANPTECRE), entre os anos de 2018 e 2023 com os descritores: logoterapia e espiritualidade. Do total de trabalhos encontrados, apenas quatro apresentaram pertinência no que diz respeito aos critérios de inclusão e exclusão estabelecidos. Constatou-se a necessidade de mais estudos atualizados que possam aprofundar a discussão acerca da convergência entre espiritualidade e sentido da vida na visão frankliana, inseridos na área de Ciências da Religião.
Espiritualidade e juventude: entre a busca por sentido e os sintomas contemporâneos
Authors: Dentz René
Published: February 2025

Este artigo aborda o mal-estar contemporâneo decorrente da centralidade do corpo e da busca incessante pela otimização da performance, que gera estresse e pânico social. O objetivo da reflexão é analisar como essa pressão resulta em uma espacialização dominante da experiência subjetiva e em respostas como a hiperatividade, explosividade e impulsividade. A hipótese levantada é que a falta de simbolização adequada e a especialização somática do corpo limitam a subjetividade, eliminando horizontes de expansão. A metodologia utilizada combina análise psicanalítica e teológica, com foco na espiritualidade contemporânea e seus desafios, como o narcisismo e a teologia da prosperidade. A conclusão aponta que o narcisismo impulsionado pelo consumismo e a estetização da existência enfraquecem os laços sociais, resultando em uma sociedade marcada pela pós-verdade, onde a emoção supera a razão, criando uma crise de autenticidade nas relações e nos rituais simbólicos.
Antioxidative constituents of Mitragyna diversifolia plant extract and their protective effect on H2O2-induced oxidative stress in L6 myotubes
Authors: Hama Ilham , Vonghirundecha Phanita , Wungsintaweekul Boonsong , Boonsut Rinnapat , Limsuwanchote Supattra , Wungsintaweekul Juraithip
Published: February 2025

This study aimed to evaluate the antioxidative constituents of Mitragyna diversifolia (Wall. ex G. Don) Havil. (MD). Total phenolic, total condensed tannin, and total flavonoid contents were determined. Antioxidant activities were assessed using colorimetric assays. The results indicated that the leaf crude extract (LCE) had the highest total phenolic, total condensed tannin, and total flavonoid contents compared to the extracts from branches, stem barks, and fruits. The antioxidative capacity of LCE exhibited IC50 values of 459.19 ± 9.08 μg/ml for 2,2-diphenyl-1-picrylhydrazyl assay and 150.93 ± 7.59 μg/ml for lipid peroxidation assay, with an ferric ion reducing antioxidant power value of 279.88 ± 2.54 μM gallic acid equivalent/g extract. After fractionating the LCE through the Toyopearl® HW-40 column, the enriched polyphenolic fraction (Fr 5) was obtained. The chemical profiles of Fr 5 using high-performance thin-layer chromatography and liquid chromatography-electrospray ionization tandem mass spectrometry were constructed. All fractions were further evaluated for their protective effect on H2O2-induced oxidative stress in L6 myotubes cell line. The protective effect was found in cells treated with 25–100 μg/ml of Fr 5. The present study concluded that the enriched polyphenolic fraction of MD has antioxidative potential and reduces oxidative stress in L6 myotubes.
Ultrahigh-Field Magnetic Resonance Imaging: Current Status and Perspectives
Authors: Bolin Qin  , Jia-Hong Gao  ,   1 Beijing City Key Laboratory for Medical Physics and Engineering, School of Physics, Peking University, Beijing 100871, China;,   2 Center for MRI Research, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China;,   3 McGovern Institute for Brain Research, Peking University, Beijing 100871, China
Published: February 2025

Magnetic resonance imaging (MRI) is one of the most important imaging modalities used in clinical radiology research and diagnosis due to its non-invasive nature, absence of ionizing radiation, high soft tissue contrast, and diverse imaging capabilities. However, traditional MRI is limited by a relatively low signal-to-noise ratio (SNR), which can be enhanced by increasing the strength of the main magnetic field. Ultra-high field MRI (UHF-MRI), an emerging technology, typically refers to MRI systems with a main magnetic field strength of 7 T or higher. Compared to conventional MRI, UHF-MRI improves image SNR and extends the boundaries of spatial resolution and detection sensitivity. These advancements not only provide clinicians with more detailed and accurate bioimaging data but also open new research avenues in fields such as life sciences and cognitive neuroscience. This paper introduces the historical development and theoretical foundations of UHF-MRI, highlights its advantages over conventional MRI, and summarizes current research on UHF-MRI applications in human brain imaging, with a focus on functional and metabolic studies. Additionally, the challenges of UHF-MRI are discussed, and potential future research directions are proposed.
A Phaseless Source Reconstruction Method Based on SVD Regularization and FISTA
Authors: Deng Dian-Jun  , Li Yan  ,   School of Information Engineering, China Jiliang University & Key Laboratory of Electromagnetic Wave Information Technology and Metrology of Zhejiang Province, Hangzhou 310018, China
Published: February 2025

This paper proposes a phaseless radiation source reconstruction method based on singular value decomposition (SVD) regularization and fast iterative shrinkage-thresholding algorithm (FISTA), aimed at efficiently identifying electromagnetic interference (EMI) sources in integrated circuits (ICs). The method acquires electromagnetic field data through near-field scanning and reconstructs an equivalent dipole array on the surface of the radiation source using the source reconstruction method (SRM). During the reconstruction process, the SVD regularization term enhances the algorithm's stability and noise resistance, while FISTA accelerates the convergence speed.
To validate the effectiveness of the proposed method, dipole array reconstruction was first performed using near-field data at a height of 5mm for a patch antenna simulation model, followed by an analysis of magnetic field data at a 10mm validation plane. At the 35th iteration, the total relative error of the reconstruction was 1.21%. The influence of the regularization parameter α on the results was then investigated, and it was found that α = 0.05 yielded the smallest error. The method was also tested under different Gaussian white noise conditions, with relative errors remaining below 5%, demonstrating strong robustness.
Finally, chip experiments were conducted to verify the method. The proposed method converged stably within 35 iterations, with a relative error of 2.3% in the reconstruction results. The total iteration time is 61.7% of the single-layer phaseless interpolation algorithm, and the relative error is reduced by 52% compared to the double-layer phasless iteration algorithm.The experimental results demonstrate that the proposed method can efficiently and accurately reconstruct phaseless radiation sources, with good noise robustness, making it suitable for EMI analysis in integrated circuits.
The effect of perioperative probiotics and synbiotics on postoperative infections in patients undergoing major liver surgery: a meta-analysis of randomized controlled trials
Authors: Wu Haopeng , Guan Zhihui , Zhang Kai , Zhou Lingmin , Cao Lanxin , Mou Xiongneng , Cui Wei , Tian Baoping , Zhang Gensheng
Published: February 2025

Objective

To evaluate the effect of perioperative probiotics or synbiotics on the incidence of postoperative infections following major liver surgery.

Design

Meta-analysis

Data sources

PubMed, Embase, Scopus, and the Cochrane Library for relevant English-language studies published up to February 21st, 2024.

Eligibility criteria

Randomized controlled trials evaluating perioperative probiotics or synbiotics for preventing postoperative infections in patients undergoing major liver surgery.

Data extraction and synthesis

Outcomes included postoperative infection incidence, antibiotic therapy duration, length of stay in intensive care unit (ICU) and hospital. A random-effect model was adopted for the meta-analysis. The quality of included studies was evaluated using the Cochrane risk of bias tool.

Results

Ten studies involving 588 patients were included. Pooled analyses revealed that perioperative probiotics or synbiotics significantly reduced postoperative infection incidence (RR 0.36, 95% CI [0.24–0.54], P < 0.0001, I2 = 6%) and antibiotic therapy duration (MD −2.82, 95% CI [−3.13 to −2.51], P < 0.001, I2 = 0%). No significant differences were observed in length of stay in ICU (MD −0.25, 95% CI [−0.84–0.34], P = 0.41, I2 = 64%) or length of stay in hospital (MD −1.25, 95% CI [−2.74–0.25], P = 0.10, I2 = 56%).

Conclusions

This meta-analysis suggests that perioperative administration of probiotics or synbiotics may reduce the incidence of postoperative infections and duration of antibiotic therapy. Their use as adjunctive therapy during the perioperative period could be considered for patients undergoing major liver surgery.
Study on mechanical properties of polyurethane elastomers in different strength tests
Authors: Żaba Krzysztof , Balcerzak Maciej , Kuczek Łukasz
Published: February 2025

Elastomeric materials are used in the methods of plastic forming of sheets made of difficult-to-deform materials. This article presents the results of strength tests of selected elastomeric materials intended for sheet metal stamping. Polyurethane elastomers with a hardness of 50, 70 and 90 Sh A were used for the tests. The behaviour of the materials was determined in a simple compression test, a volumetric compression test and a uniaxial tensile test. In the case of the simple compression test, the values of the maximum force for a set punch travel of 3 mm were 1400 N, 2250 N and 4950 N for samples with hardnesses of 50, 70 and 90 Sh A, respectively. In a volumetric compression test, the maximum compressive force for a sample with a hardness of 90 Sh A was more than twice lower than the compressive force of samples with a hardness of 50 and 70 Sh A. In the tensile tests, the values ​​of the obtained strains ranged from about 750% for the sample with a hardness of 50 Sh A to about 1350% for the sample with a hardness of 90 Sh A.
Exploring Empathy and Satisfaction Dynamics in Veterinary Medical Interviews among Companion Animal Veterinarians and Pet Owners in Kerala, India
Authors: D’souza Ryan Leander , George P. Reeja , Senthilkumar R. , Jiji R.S. , Gleeja V.L. , Y. Ajith
Published: February 2025

Veterinary medical interviews are pivotal to companion animal care, directly influencing clinical outcomes and client satisfaction. This study explores the satisfaction levels of companion animal veterinarians and pet owners with these interviews and highlights a disturbing trend with regard to the role of veterinarian empathy and its effect on veterinarian satisfaction in this process. The study was conducted in the state of Kerala in India among 60 randomly selected companion animal veterinarians and 60 pet owners selected at random from four districts with the highest canine populations in the area of study. Results indicated that most veterinarians reported low (46.70 per cent) to medium (48.30 per cent) satisfaction despite medium (35.00 per cent) to high (63.30 per cent) self-rated empathy levels. The results of this study indicated that most of the pet owners reported a medium (31.70 per cent) to high (63.30 per cent) of satisfaction with the interviews. A significant positive association was found between veterinarian satisfaction and empathy; however, veterinarian satisfaction was negatively associated with owners’ perception of communication behaviours. The lack of association between veterinarian empathy and owner satisfaction highlights the complex interplay between empathy, professional satisfaction, and client perceptions. Findings suggest that empathic over-arousal may contribute to reduced veterinarian well-being, potentially reflecting compassion fatigue. This study underscores the need for further exploration of empathy’s dual role as a professional asset and risk factor in veterinary medicine to enhance the communication process and client satisfaction with the veterinary medical interval.
Future-Proofing Data: Assessing the Feasibility of Post-Quantum Cryptographic Algorithms to Mitigate ‘Harvest Now, Decrypt Later’ Attacks
Authors: Olutimehin Abayomi Titilola , Joseph Sunday Abayomi , Ajayi Adekunbi Justina , Metibemu Olufunke Cynthia , Balogun Adebayo Yusuf , Olaniyi Oluwaseun Oladeji
Published: February 2025

This study evaluates the feasibility of post-quantum cryptographic (PQC) algorithms in mitigating "Harvest Now, Decrypt Later" (HNDL) attacks as quantum computing advances threaten classical encryption. Using datasets from the NIST Post-Quantum Cryptography Project, Deloitte’s PQC Adoption Survey, and IBM & Google Quantum Roadmaps, the study applied statistical modeling, Monte Carlo simulations, and ARIMA forecasting to assess PQC security resilience, adoption readiness, and quantum decryption feasibility. The findings indicate that CRYSTALS-Kyber and CRYSTALS-Dilithium outperform RSA-2048 and ECC-256 in quantum resistance, with attack cost thresholds exceeding 1.91×10101.91 \times 10^{10}1.91×1010 compared to 2.24×1082.24 \times 10^82.24×108 for RSA-2048. Industry adoption varies, with government PQC implementation at 79%, finance at 67%, and healthcare lagging at 48%. Quantum decryption probability remains negligible until 2029 but rises to 78.6% by 2033. This study addresses the critical challenge of post-quantum cryptographic (PQC) adoption amid growing quantum threats, particularly "Harvest Now, Decrypt Later" (HNDL) attacks. By evaluating PQC security resilience, industry adoption, and quantum decryption feasibility, the findings provide strategic insights for policymakers and cybersecurity experts. Highlighting the vulnerabilities of CRYSTALS-Kyber to side-channel attacks, this research underscores the need for continuous cryptanalysis, hybrid encryption models, and adaptive security frameworks to future-proof data.Organizations must accelerate PQC adoption, integrate hybrid cryptographic models, enforce regulatory policies, and sustain cryptanalysis efforts to ensure long-term security.
Simulation of Solute Transport in a Finite Aquatic Ecosystem Using the Two-Dimensional Advection-Dispersion Equation in Cylindrical Coordinates: Analysis of the Impact of Emergent and Rigid Vegetation
Authors: Penka Ledoux Michel , Ewoukem Thomas Efole , Ndongo Barthelemy
Published: February 2025

Aquatic porous media experience the intrusion of pollutants from natural or anthropogenic sources, affecting the health of aquatic ecosystems. The retention and diffusion of pollutants strongly depend on parameters such as vegetation volumetric fraction (φ), porosity, and medium density. This study numerically solves the advection-dispersion equation in cylindrical coordinates using finite difference methods to evaluate pollutant concentration profiles in an initially contaminated aquatic porous medium, where flow velocity and dispersion coefficient vary with the vegetation fraction. The results reveal a marked sensitivity of concentration profiles to an increase in vegetation fraction, which reduces pollutant diffusion, while higher porosity promotes their dispersion. Furthermore, zones of high-medium density accumulate more pollutants, increasing local concentrations. These interactions influence aquatic ecosystems, with elevated concentrations potentially disrupting flora and fauna. This study highlights the importance of considering these parameters to develop effective strategies for the management and preservation of aquatic environments.
Decolonizing Peace in Africa: Why African Traditions Hold a Key to Sustainable Peace?
Authors: Thelma Chanda Chansa , Prince Bwalya , Sylvester Chisebe , Pedzisai Domboka Robert , Banda Esther
Published: February 2025

Overview: The study on decolonizing peace highlights the critical role of African traditions in fostering peace by emphasizing indigenous approaches to conflict resolution, community cohesion, and restorative justice.
Body of Knowledge: This study emphasizes the importance of embracing indigenous traditions and cultural practices as foundational elements for fostering sustainable peace in Africa. African traditions, rooted in communal values, restorative justice, and consensus-building, offer sustainable alternatives to Western-centric peace building models, which often overlook the continent's unique social, historical, and cultural contexts.
Methods: The study was conducted in Lusaka district, the capital city of Zambia. The sample consisted 50 research participants. A purposive sampling technique was used to select key informants such as traditional chiefs, peace practitioners, academicians, and policymakers. Moreover, snowball sampling helped identify additional participants such as church leaders with relevant insights. The data collection process involved conducting semi-structured interviews and focus groups discussions (FGDs).The data collected were analyzed using study themes and content analysis.
Results: The findings revealed that that African traditions, such as Ubuntu and communal consensus-building, foster inclusivity and a shared sense of responsibility, enabling communities to address conflicts collaboratively and restore relationships. Additionally, African peace building frameworks, rooted in collective decision-making, respect for elders, and culturally ingrained reconciliation practices, offer sustainable alternatives to Western-centric models that often overlook local contexts.
Recommendation: Schools, universities, and civil society organizations should promote the communal values to cultivate a generation that prioritizes dialogue, cooperation, and collective well-being over adversarial approaches to conflict resolution.
Areca Catechu Biochar and Nano-Biochar as Adsorbents for Congo Red: Synthesis, Characterization, and Performance Evaluation
Authors: Adawiyah Robiatul , Yuliasari Nova , Hanifah Yulizah , Palapa Neza Rahayu
Published: February 2025

The presence of hazardous synthetic dyes such as Congo Red in industrial wastewater poses a significant environmental threat. This study explores the potential of biochar (BC) and nano-biochar (nano-BC), derived from Areca catechu husk as sustainable adsorbents for dye removal. Nano-BC was synthesised via hydrothermal carbonisation and mechanical ball milling, leading to enhanced structural and surface properties. X-ray Diffraction (XRD) revealed that the Pinang husk is predominantly amorphous, while BC exhibits increased crystallinity with sharp peaks, and nano-BC demonstrates the highest crystallinity and nanostructural refinement. Fourier Transform Infra Red (FTIR) confirmed the transformation of aliphatic-rich raw biomass into aromatic-dominant structures in BC and nano-BC, with nano-BC showing more pronounced graphite-like features. Scanning Electron Microscope (SEM) illustrated the morphological evolution, with nano-BC exhibiting refined, uniformly porous structures. BET analysis revealed that nano-BC has a significantly higher surface area 41.38 m²/g and smaller pore size 8.4928 nm compared to BC 22.38 m²/g and 15.39 nm, enhancing adsorption capacity. Furthermore, the adsorption kinetics followed the pseudo-second-order model, and isothermal analysis confirmed monolayer adsorption with the highest maximum adsorption capacity (Qmax = 154.526 mg/g). These findings highlight the superior adsorption performance of nano-BC, emphasising its potential for environmentally friendly water treatment applications. Copyright © 2025 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Effects of Cocaine on the Placenta
Authors: Cejtin Helen E. , Young Stephanie A. , Ungaretti Joy , Anciaux Dominique , Imam Shaheen , Teopengco Ellen , Sander C. Maureen
Published: July 2002

Adverse perinatal outcomes of gravidas using cocaine is well documented, but the effects on the placenta have been difficult to elucidate due to confounding factors such as concurrent use of other drugs. This study compares pathologic findings of 26 placentas from women who used only cocaine during pregnancy with findings from 26 controls. All women were from a similar socio-economic class and were controlled for gestational age and tobacco use. None of the cocaine placentas were from women whose toxicology screens were positive for drugs other than cocaine.

In the 26 cocaine placentas, there was 1 infarct, 3 chronic villitis, and 1 segmental fibrosis, with none present in the controls. In the control group, there was 1 decidual vasculopathy and 1 thrombus in a maternal vessel, but none were in the cocaine placentas. Each group had 1 thrombus in a fetal vessel. The study group showed 6 cases of chorioamnionitis and 1 funisitis; the control group had 10 and 4 cases, respectively. None of the above or seven other features showed a statistically significant difference between the cases and controls. Cocaine is a potent vasoconstrictive agent that blocks re-uptake of norepinephrine at the adrenergic nerve terminals. Our study suggests that cocaine does not cause an increased incidence of any of the 15 clearly recognizable placental features examined.
Band 3 protein—cholesterol interactions in erythrocyte membranes
Authors: Schubert Dieter , Boss Karin
Published: July 2002

Band 3 protein of the human erythrocyte membrane, the anion transport protein, possesses a high affinity steroid binding site. In mixed phospholipid—cholesterol monolayers, the state of occupancy of this site is positively correlated with their cholesterol and sphingomyelin content and negatively with their glycerophospholipid content. We suggest that, in the erythrocyte membrane, the binding site is an inhibitory site of anion transport and that the modulation of its state of occupancy by the membrane lipid is responsible for the negative correlation of anion transport with the membrane's content of cholesterol and sphingomyelin and the positive correlation with the phosphatidylcholine content
Relaxation of chromatin structure upon removal of histones H2A and H2B
Authors: Jordano Juan , Montero Francisco , Palacián Enrique
Published: July 2002

Modification of chromatin from chicken erythrocytes with dimethylmaleic anhydride is accompanied by its solubilization and the dissociation of histones H1, H5, H2A and H2B. Histone H1 is the first to dissociate and H5 the last. After regeneration of the modified amino groups, residual chromatin preparations with different histone composition were studied by circular dichroism and thermal denaturation. In addition to the effects produced by the lack of histones HI and H5, both techniques show a substantial relaxation of chromatin structure induced by the loss of histones H2A and H2B, which appear to play an important role in the superhelical folding of DNA.
Single‐electron transfer processes and the reaction mechanism of enzymic degradation of lignin
Authors: Harvey P.J. , Schoemaker H.E. , Bowen R.M. , Palmer J.M.
Published: July 2002

Lignin degradation
Single‐electron transfer
Cα‐Cβ bond cleavage
Phanerochaete chrysosporium
Peroxidase compound I
Inhibition of serum complement haemolytic activity by lipid vesicles containing phosphatidylserine
Authors: Comis Alfio , Easterbrook-Smith Simon B.
Published: July 2002

The effect of artificial model membranes on the complement system was investigated. Incubation of the model membranes with human serum resulted in consumption of complement haemolytic activity when phosphatidylserine‐containing vesicles were used. The activation of the complement system appeared to proceed through the alternative pathway. This conclusion was supported by the failure of [125I]Clq to bind to the membranes suggesting that the classical pathway was not involved. Although always obtained when phosphatidylserine was present in the model membranes, the activation of complement was enhanced by the contemporaneous presence of phosphatidylethanolamine. Liposomes prepared from lipid extracts of red blood cells were also able to stimulate a concentration‐dependent activation of complement. Fresh, intact erythrocytes, however, could not initiate the same effects unless opsonized by antibodies. When artificially aged in vitro, red blood cells were lysed if incubated with normal human serum or with Clq‐depleted serum. However, no lysis was obtained if the ‘aged’ erythrocytes were incubated with serum pretreated with ammonia to destroy the C3 component of complement. It is suggested that one of the mechanisms of macrophage recognition of senescent erythrocytes might be provided by the activation of the alternative pathway of complement if phosphatidylserine becomes exposed on the surface of the aging cells.
Primary structure of the site on bovine hormone‐sensitive lipase phosphorylated by cyclic AMP‐dependent protein kinase
Authors: Garton Andrew J. , Campbell David G. , Cohen Philip , Yeaman Stephen J.
Published: July 2002

The primary structure of a region on hormone‐sensitive lipase was determined to be: Lys‐Thr‐Glu‐Pro‐Met‐Arg‐Arg‐Ser‐Val‐Ser‐Glu‐Ala‐Ala‐Leu‐Thr‐Gln‐Pro‐Glu‐Gly‐Pro‐Leu‐Gly‐Thr‐Asp‐Ser‐Leu‐Lys. Ser‐8 was the only residue in the intact protein phosphorylated by cyclic AMP‐dependent protein kinase. However, Ser‐10 also appeared to be present in a phosphorylated form, suggesting that it is a target for a distinct protein kinase in vivo.
Alterations of lipid composition in Friend leukemia cell tumors in mice treated with tumor necrosis factor‐α
Authors: Bravo E. , Carpinelli G. , Proietti E. , Belardelli F. , Cantafora A. , Podo F.
Published: July 2002

Lipid analyses were carried out on transplantable murine Friend leukemia cell tumors, 6 h after intratumoral administration of tumor necrosis factor‐α (TNF). The levels of the major phospholipid classes were uniformly decreased to about 70% of control values; free fatty acids were increased to about 170%; diacylglycerol was decreased to about 50% and triacylglycerol, the main lipid component, was not significantly altered. These results analysed in the light of concomitant alterations in the levels of phospholipid precursors and catabolites (determined in previous 31P NMR studies) and histological modifications demonstrated that at early stages of TNF‐induced inhibition of tumor growth (a) phospholipid catabolism was significantly enhanced; (b) morphological changes were apparently correlated with alterations in the levels of phosphatidylcholine and its catabolic products.
Lipoprotein(a) enhances plasma clot lysis in vitro
Authors: Mao Simon J.T. , Tucci Michelle A.
Published: July 2002

Human plasma lipoprotein(a) (Lp(a)) is a macromolecular complex that contains a protein homologous to plasminogen, the precursor of plasmin. We confirmed recent reports that Lp(a) is not activated by streptokinase or tissue plasminogen activator (t‐PA) to yield plasmin‐like activity. In testing the hypothesis that Lp(a) can competitively inhibit plasma clot lysis mediated by plasmin, the present study shows that Lp(a) significantly enhanced plasma clot lysis mediated by streptokinase or t‐PA. The enhancement, however, was not observed in a plasmin‐mediated clot lysis using a purified fibrinogen system. The addition of α‐2‐antiplasmin (α2‐plasmin inhibitor) to this system inhibited fibrinolysis; however, no inhibition was observed in the presence of Lp(a). One potential explanation for the Lp(a)‐enhanced plasma clot lysis is that Lp(a) neutralizes the activity of α2‐antiplasmin present in plasma, thereby restoring the activity of plasmin to lyse the clot.
ADP‐ribosylated elongation factor 2 (ADP‐ribosyl‐EF‐2) is unable to promote translocation within the ribosome
Authors: Davydova E.K. , Ovchinnikov L.P.
Published: July 2002

Elongation factor 2 (EF‐2), ADP‐ribosylated in vitro by the A‐fragment of diphtheria toxin, can (in the presence of GMPPCP) form stable corn plexes with ribosomes regardless of whether the ribosomes are empty or carrying poly(U) and Phe‐tRNA in the A‐site. Despite its efficient binding to ribosomes, ADP‐ribosyl‐EF‐2, in contrast to the non‐modified EF‐2 is unable to promote the shift of Phe‐tRNA from the A‐site to the P‐sit of the ribosome as determined by the puromycin reaction, i.e. it is incapable of promoting the translocation reaction within the ribosome.
Evidence for the requirement of proteolysis in LH stimulated cyclic AMP production and steroidogenesis in Leydig cells
Authors: West Anthony P. , Phipp Laura H. , Cooke Britin A.
Published: July 2002

We have investigated the effect of protease activity on cyclic AMP production and steroidogenesis in rat testis, mouse testis and mouse tumour Leydig (MA10) cells. LH‐, dibutyryl cyclic AMP‐, and forskolin‐stimulated steroidogenesis, but not 22R(OH) cholesterol conversion to pregnenolone, was inhibited by protease inhibitors. In mouse Leydig cells, LH but not forskolin or cholera toxin stimulated cyclic AMP production was inhibited by protease inhibitors. These results suggest that steroidogenesis in Leydig cells requires proteolysis before the conversion of cholesterol to pregnenolone. In the mouse but not rat Leydig cells, LH‐stimulated cyclic AMP production is also dependent on proteolysis.
Boar spermadhesins AQN‐1 and AWN are sperm‐associated acrosin inhibitor acceptor proteins
Authors: Sanz Libia , Calvete Juan J. , Jonáková Véra , Töpfer-Petersen Edda
Published: July 2002

Trypsin‐like inhibitors secreted by the male accessory sex glands have been identified in the seminal plasma of every mammalian species so far investigated. They bind to acceptor molecules on the anterior part of ejaculated sperm, and are thought to play a role in the capacitation of spermatozoa stabilizing zona pellucida binding sites during sperm uterine passage, and then dissociating to allow sperm‐egg's zona pellucida interaction. Here we report the identification of acrosin inhibitor acceptor molecules isolated from boar seminal plasma. These proteins termed AQN‐1 and AWN, belong to the recently described spermadhesin protein family, whose members have been implicated in sperm‐zona pellucida recognition events. Thus, members of the spermadhesin family, although not possessing detectable enzymatic activity, show features of serine proteinases, and may be involved in both sperm capacitation and sperm‐egg recognition and binding events.
Level of expression controls modes of gating of a K+ channel
Authors: Moran Ofira , Schreibmayer Wolfgang , Weigl Lukas , Dascal Nathan , Lotan Ilana
Published: July 2002

Several distinct subfamilies of K+ channel genes have been discovered by molecular cloning, however, in some cases the structural differences among them do not account for the diversity of K+ current types, ranging from transient A‐type to slowly inactivating delayed rectifier‐type, as members within each subfamily have been shown to code for K+ channels of different inactivation kinetics and pharmacological properties. We show that a single K+ channel cDNA of the Shaker subfamily (ShH4) can express in Xenopus oocytes not only a transient A‐type K+ current but also, upon increased level of expression, slowly inactivating K+ currents with markedly reduced sensitivity to tetraethylammonium. In correlation with the macroscopic currents there are single‐channel gating modes ranging from the fast‐inactivation mode which underlies the transient A‐type current, to slow‐inactivation modes characterized by bursts of longer openings, and corresponding to the slowly inactivating macroscopic currents.
Functional expression of a plant plasma membrane transporter in Xenopus oocytes
Authors: Boorer K.J. , Forde B.G. , Leigh R.A. , Miller A.J.
Published: July 2002

A full‐length cDNA clone for the H+/hexose co‐transporter (STP1) from Arabidopsis thaliana has been transcribed in vitro and the mRNA injected into Xenopus oocytes. Under optimized conditions, oocytes injected with the STPI mRNA accumulated 3‐O‐[methyl‐14C]glucose at rates of more than a 1000‐fold greater than water‐injected control oocytes. A hexose‐elicited depolarization of the oocyte membrane potential was demonstrated, and uptake was shown to be stimulated by low external pH, confirming the activity of a H+/hexose co‐transport system. This is the first example of the functional expression of a plant membrane transporter in oocytes.
Effect of different endothelin receptor antagonists and of the novel non‐peptide antagonist Ro 46‐2005 on endothelin levels in rat plasma
Authors: Löffler Bernd-Michael , Breu Volker , Clozel Martine
Published: July 2002

The goal of our study was to evaluate and compare the effects of receptor blockade with different endothelin (ET) receptor antagonists on plasma concentrations of ET‐1, big ET‐1 and ET‐3 in conscious rats. Ro 46‐2005 (10 mg/kg, i.v.), a novel non‐peptide antagonist of both ETA and ETB receptors, increased the concentrations of ET‐1 in plasma to 200 ± 13% of basal levels (P < 0.001). This effect was dose‐ and time‐dependent and reached a maximum at 15 min. Ro 46‐2005 had no effect on plasma concentrations of big ET‐1 and only a minor effect on those of ET‐3. In contrast to Ro 46‐2005, the selective peptide ETA antagonists BQ‐123 and FR‐139317 had no effect on plasma ET‐1 concentrations. The increase in plasma ET‐1 concentrations by Ro 46‐2005 was most likely not due to de novo synthesis, since big ET‐1 levels were not increased and peak levels were reached early after compound injection, but perhaps to displacement of ET‐1 from the ETB receptors.
The human muscarinic M1 acetylcholine receptor, when expressed in CHO cells, activates and downregulates both Gqα and G11α equally and non‐selectively
Authors: Mullaney Ian , Mitchell Fiona M. , McCallum J.Fraser , Buckley Noel J. , Milligan Graeme
Published: July 2002

CHO cells express both of the phosphoinositidase C‐linked G‐proteins Gq and G11 G11α is some 2.5‐fold more highly expressed than Gqα in membranes of these cells. Following transfection and stable expression of CHO cells with DNA encoding the human muscarinic M1 acetylcholine (HM1) receptor, chronic treatment of the cells with the cholinergic agonist carbachol resulted in down‐regulation of membrane levels of both Gqα and G11α. Dose‐response curves to carbachol produced identical EC50 values for agonist‐induced down‐regulation of the two G‐proteins and both were down‐regulated with the same time course. These data indicate that the HM1 receptor interacts with and activates both Gqα and G11α equivalently and non‐selectively in a whole cell system in which the receptor has access to both G‐proteins.
Modulation of phagocytosis by anisoosmolarity and betaine in rat liver macrophages (Kupffer cells) and RAW 264.7 mouse macrophages
Authors: Warskulat Ulrich , Zhang Fan , Häussinger Dieter
Published: July 2002

Hypoosmotic exposure (205 mosmol/l) of rat liver macrophages (Kupffer cells) for 12 h stimulated phagocytosis of latex particles by about 20%, whereas hyperosmotic exposure (405 mosmol/l) resulted in 30–40% inhibition. Inhibition of phagocytosis by hyperosmolarity was fully prevented in the presence of betaine, which acts as an osmolyte in liver macrophages. When hyperosmotically exposed Kupffer cells were preloaded with betaine, induction of phagocytosis by addition of latex particles led to the stimulation of betaine efflux from the cells. Stimulation of phagocytosis also inhibited the hyperosmolarity‐induced cumulative uptake of betaine into Kupffer cells, but did not prevent the hyperosmolarity‐induced increase in BGT1‐mRNA levels. Whereas these findings suggest an involvement of cell volume and betaine in the regulation of phagocytosis in Kupffer cells, betaine transport was not affected upon induction of phagocytosis in RAW 264.7 mouse macrophages. The findings are compatible with a role of betaine in maintaining cell volume homeostasis during phagocytosis in Kupffer cells, but not in RAW 264.7 mouse macrophages. This may be relevant for the maintenance of liver hemodynamics, since volume changes of liver macrophages following ingestion of phagocytozable material might otherwise impair sinusoidal perfusion.
Serotonin-related, anxiety/aggression-driven, stressor-precipitated depression. A psycho-biological hypothesis
Authors: van Praag HM
Published: July 2002

The concept of a 5-HT related, anxiety and/or aggression-driven, stressor-precipitated depression is formulated and discussed. It comprises the following elements. The 5-HT ergic disturbances found in some depressed individuals - and of them particularly lowered CSF 5-HIAA - are linked to the anxiety- and the aggression-components of the depressive sydrome. In this type of depression - called 5-HT related depression - dysregulation of anxiety and/or aggression are primordial and mood lowering is a derivative phenomenon. In other words this is a group of anxiety/aggression-driven depressions. The 5-HT ergic impairment in certain types of depression is a trait-phenomenon, ie, persists during remission. This disturbance makes the individual susceptable for perturbation of anxiety- and aggression-regulation. Anxiety and (overt or suppressed) anger, are core constituents of the stress-syndrome. Thus, the 5-HT ergic disturbance will induce a heightened sensitivity for stressful events, ie, the latter will induce more readily than normal, stress phenomena , among which anxiety and anger. The latter psychological features induce lowering of mood and thus “drive” the patient into a fullblown depression. Furthermore it is predicted that anxiolytics and serenics (ie, anti-aggressive drugs) that act via normalisation of 5-HT ergic circuits, will exert a antidepressant effect in 5-HT related depression,in additionto their therapeutic actions in anxiety disorders and states of increased aggressiveness, respectively. The exact nature of the 5-HT ergic impairment in 5-HT related depression has yet to be elucidated.
Inhibition of chymase reduces vascular proliferation in dog grafted veins
Authors: Takai Shinji , Yuda Atsushi , Jin Denan , Nishimoto Masayoshi , Sakagichi Masato , Sasaki Shinjiro , Miyazaki Mizuo
Published: July 2002

We investigated the effect of a chymase inhibitor Suc‐Val‐Pro‐PheP(OPh)2 on the proliferation of the grafted vein in dog. By 28 days after the operation, the mean intimal area of the grafted vein in the placebo group was 3.24±0.32 mm2. The intimal area of the grafted vein in the chymase inhibitor‐treated group was reduced to 63.9%. In the placebo group, the activities of chymase and angiotensin‐converting enzyme in grafted vein were significantly increased 15‐ and 2‐fold, respectively. In the chymase inhibitor‐treated group, chymase activity in the grafted veins was decreased significantly. These findings suggest that inhibition of chymase appears useful for preventing vascular proliferation.
κ‐Opioid inhibits catecholamine biosynthesis in PC12 rat pheochromocytoma cell
Authors: Takekoshi Kazuhiro , Ishii Kiyoaki , Kawakami Yasushi , Isobe Kazumasa , Nakai Toshiaki
Published: July 2002

It was reported that nicotine‐induced dopamine release in the rat pheochromocytoma cell line, PC12 cells, was inhibited by κ‐opioid. However, it is not known whether inhibition of catecholamine biosynthesis is involved in the inhibitory mechanisms of κ‐opioids in PC12 cells. U‐69593 (a κ‐opioid agonist: ≥100 nM) significantly inhibited the nicotine‐induced increase of tyrosine hydroxylase (TH, a rate‐limiting enzyme in biosynthesis of catecholamine) enzyme activity and TH mRNA levels. These inhibitory effects were completely reversed by naloxone and nor‐binaltorphimine dihydrochloride (nor‐BNI), a specific κ‐antagonist, whereas pertussis toxin (PTX) only partially reversed this inhibitory effect. Also, U‐69593 (≥100 nM) significantly inhibited the nicotine‐induced increase of cAMP production. This inhibitory effect was completely reversed by naloxone and nor‐BNI, whilst only partially reversed by PTX. Moreover, U‐69593 (≥100 nM) significantly inhibited the nicotine‐induced increase of both the TH protein level and intracellular catecholamine levels. These results indicate that the anti‐cholinergic actions of κ‐opioid can be explained partially by its inhibition of both TH enzyme activity and TH synthesis, through suppression of the cAMP/protein kinase A pathway. It would also appear that the PTX‐sensitive G‐protein mediates the inhibitory effect of this pathway, at least in part.
A novel role for protein phosphatase 2A in the dopaminergic regulation of Na,K‐ATPase
Authors: Lecuona Emilia , Garcia Alphonse , Sznajder Jacob I.
Published: July 2002

Stimulation of dopaminergic type 1 (D1) receptors increases lung edema clearance by regulating Na,K‐ATPase function in the alveolar epithelium. We studied the role of serine/threonine protein phosphatases in the Na,K‐ATPase regulation by D1 agonists in A549 cells. We found that low doses of the type 1/2A protein phosphatase inhibitor okadaic acid as well as SV40 small t antigen transiently transfected into A549 cells prevented the D1 agonist‐induced increase in Na,K‐ATPase activity and translocation from intracellular pools to the plasma membrane. This was associated with a rapid and transient increase in protein phosphatase 2A activity. We conclude that D1 stimulation regulates Na,K‐ATPase activity by promoting recruitment of Na,K‐ATPases from intracellular pools into the basolateral membranes of A549 cells via a type 2A protein phosphatase.