Can the Lewis basicity of an isolated solvent molecule be used for characterizing solvent effects?

2020 ◽  
Vol 16 ◽  
Author(s):  
Jean-François Gal ◽  
Pierre-Charles Maria
Keyword(s):  
Solvent Effects ◽  
Molecular Level ◽  
Solvent Molecule ◽  
Lewis Base ◽  
Bulk Liquid ◽  
Donor Number ◽  
Special Focus ◽  
Solution Processes ◽  
Inert Solvent

Background: The ubiquitous Lewis acid/base interactions are important in solution processes. Analytical chemistry may benefit of a better understanding of the role of Lewis basicity, at the molecular level or acting through a bulk solvent effect. Objective: To clearly delineate (i) the basicity at a molecular level, hereafter referred as solute basicity, and (ii) the solvent basicity, which is a bulk-liquid property. Method: The literature that relates Lewis basicity scales and solvent effects is analyzed. A special focus is placed on two extensive scales, the Donor Number, DN, and the BF3 affinity scale, BF3A, which were obtained by calorimetric measurement on molecules as solutes diluted in a quasi-inert solvent, and therefore define a molecular Lewis basicity. We discuss the validity of these solute scales when regarded as solvent scales, in particular when the basicity of strongly associated liquids is discussed. Results: We demonstrate the drawbacks of confusing the Lewis basicity of a solvent molecule, isolated as solute, and that of the bulk liquid solvent itself. Conclusion: Consequently, we recommend a reasoned use of the concept of Lewis basicity taking clearly into account the specificity of the process for which a Lewis basicity effect may be invoked. In particular, the action of the Lewis base, either as an isolated entity, or as a bulk liquid, must be distinguished.

FAITH–BASED COMMUNITIES AND POLITICS IN DULLSTROOM-EMNOTWENI: LOCAL STORIES OF IDENTITY

2016 ◽  
Vol 1 (1) ◽  
pp. 45-57 ◽  
Author(s):  
Christina Landman
Keyword(s):  
Higher Education ◽  
Service Delivery ◽  
Special Focus ◽  
Traditional Role ◽  
Cultural Conflicts ◽  
Local Identities ◽  
Political Interests ◽  
Local Municipality ◽  
The Face

A majority of the black community of Dullstroom-Emnotweni in the Mpumalanga highveld in the east of South Africa trace their descent back to the southern Ndebele of the so-called ‘Mapoch Gronden’, who lost their land in the 1880s to become farm workers on their own land. A hundred years later, in 1980, descendants of the ‘Mapoggers’ settled in the newly built ‘township’ of Dullstroom, called Sakhelwe, finding jobs on the railways or as domestic workers. Oral interviews with the inhabitants of Sakhelwe – a name eventually abandoned in favour of Dullstroom- Emnotweni – testify to histories of transition from landowner to farmworker to unskilled labourer. The stories also highlight cultural conflicts between people of Ndebele, Pedi and Swazi descent and the influence of decades of subordination on local identities. Research projects conducted in this and the wider area of the eMakhazeni Local Municipality reveal the struggle to maintain religious, gender and youth identities in the face of competing political interests. Service delivery, higher education, space for women and the role of faith-based organisations in particular seem to be sites of contestation. Churches and their role in development and transformation, where they compete with political parties and state institutions, are the special focus of this study. They attempt to remain free from party politics, but are nevertheless co-opted into contra-culturing the lack of service delivery, poor standards of higher education and inadequate space for women, which are outside their traditional role of sustaining an oppressed community.

scholarly journals Sub-Inhibitory Concentrations of Ciprofloxacin Alone and Combinations with Plant-Derived Compounds against P. aeruginosa Biofilms and Their Effects on the Metabolomic Profile of P. aeruginosa Biofilms

Antibiotics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 414
Author(s):  
Didem Kart ◽  
Tuba Reçber ◽  
Emirhan Nemutlu ◽  
Meral Sagiroglu
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Inhibitory Concentration ◽  
Molecular Level ◽  
Metabolomic Profile ◽  
Gene Expressions ◽  
New Agents ◽  
Qrt Pcr ◽  
Metabolomic Approach

Introduction: Alternative anti-biofilm agents are needed to combat Pseudomonas aeruginosa infections. The mechanisms behind these new agents also need to be revealed at a molecular level. Materials and methods: The anti-biofilm effects of 10 plant-derived compounds on P. aeruginosa biofilms were investigated using minimum biofilm eradication concentration (MBEC) and virulence assays. The effects of ciprofloxacin and compound combinations on P. aeruginosa in mono and triple biofilms were compared. A metabolomic approach and qRT-PCR were applied to the biofilms treated with ciprofloxacin in combination with baicalein, esculin hydrate, curcumin, and cinnamaldehyde at sub-minimal biofilm inhibitory concentration (MBIC) concentrations to highlight the specific metabolic shifts between the biofilms and to determine the quorum sensing gene expressions, respectively. Results: The combinations of ciprofloxacin with curcumin, baicalein, esculetin, and cinnamaldehyde showed more reduced MBICs than ciprofloxacin alone. The quorum sensing genes were downregulated in the presence of curcumin and cinnamaldehyde, while upregulated in the presence of baicalein and esculin hydrate rather than for ciprofloxacin alone. The combinations exhibited different killing effects on P. aeruginosa in mono and triple biofilms without affecting its virulence. The findings of the decreased metabolite levels related to pyrimidine and lipopolysaccharide synthesis and to down-regulated alginate and lasI expressions strongly indicate the role of multifactorial mechanisms for curcumin-mediated P. aeruginosa growth inhibition. Conclusions: The use of curcumin, baicalein, esculetin, and cinnamaldehyde with ciprofloxacin will help fight against P. aeruginosa biofilms. To the best of our knowledge, this is the first study of its kind to define the effect of plant-based compounds as possible anti-biofilm agents with low MBICs for the treatment of P. aeruginosa biofilms through metabolomic pathways.

scholarly journals Hypoxia, Acidification and Inflammation: Partners in Crime in Parkinson’s Disease Pathogenesis?

Immuno ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 78-90
Author(s):  
Johannes Burtscher ◽  
Grégoire P. Millet
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Neurodegenerative Diseases ◽  
Current Knowledge ◽  
Cell Types ◽  
Brain Cell ◽  
Special Focus ◽  
Molecular Alterations ◽  
Research Fields

Like in other neurodegenerative diseases, protein aggregation, mitochondrial dysfunction, oxidative stress and neuroinflammation are hallmarks of Parkinson’s disease (PD). Differentiating characteristics of PD include the central role of α-synuclein in the aggregation pathology, a distinct vulnerability of the striato-nigral system with the related motor symptoms, as well as specific mitochondrial deficits. Which molecular alterations cause neurodegeneration and drive PD pathogenesis is poorly understood. Here, we summarize evidence of the involvement of three interdependent factors in PD and suggest that their interplay is likely a trigger and/or aggravator of PD-related neurodegeneration: hypoxia, acidification and inflammation. We aim to integrate the existing knowledge on the well-established role of inflammation and immunity, the emerging interest in the contribution of hypoxic insults and the rather neglected effects of brain acidification in PD pathogenesis. Their tight association as an important aspect of the disease merits detailed investigation. Consequences of related injuries are discussed in the context of aging and the interaction of different brain cell types, in particular with regard to potential consequences on the vulnerability of dopaminergic neurons in the substantia nigra. A special focus is put on the identification of current knowledge gaps and we emphasize the importance of related insights from other research fields, such as cancer research and immunometabolism, for neurodegeneration research. The highlighted interplay of hypoxia, acidification and inflammation is likely also of relevance for other neurodegenerative diseases, despite disease-specific biochemical and metabolic alterations.

scholarly journals 26.A. Workshop: Assessing the role of policies and actions to address childhood obesity

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
◽  
Keyword(s):  
Public Health ◽  
Childhood Obesity ◽  
Stakeholder Engagement ◽  
Special Focus ◽  
Policy Options ◽  
Sustainable Solutions ◽  
Relevant Evidence ◽  
Multi Stakeholder ◽  
The Impact

Abstract   Childhood obesity has grown to become one of the most dramatic features of the global obesity epidemic, with long-term consequences. The spread of obesity has been fueled by changes in social norms and living environments that have shaped individual behaviours making them conducive to excessive and imbalanced nutrition, sedentary lifestyles, and ultimately obesity and associated diseases. The STOP project will aim to generate scientifically sound, novel and policy-relevant evidence on the factors that have contributed to the spread of childhood obesity in European countries and on the effects of alternative technological and organisational solutions and policy options available to address the problem. STOP will translate the evidence gathered and generated into indicators and measurements, policy briefs and toolkits and multi-stakeholder frameworks. A special focus of STOP is understanding the stakeholders' networks and drivers of stakeholders' action. STOP will establish new ways for policy-relevant evidence to be generated, made available and used in the design and implementation of effective and sustainable solutions for childhood obesity at the EU, national and local levels. Each of the policy work packages will: Produce evidence syntheses and impact simulations for different policy approaches;Assess selected policy approaches and actions in children cohorts and other relevant settings;Devise policy toolkits and policy guidance to support the adoption and implementation of specific actions by relevant actors;Establish a country-based European accountability and monitoring framework in each policy area. The workshop aims to: Showcase the impact of different policy options evaluated throughout the STOP project;Increase participants' understanding and awareness of the opportunities and challenges associated with the implementation of selected policies;Increase awareness of public health professionals of the importance of overcoming siloes in identifying and implementing public health policies;Increase the understanding of multi-stakeholder engagement. The discussion will explore the role of stakeholders across different policy areas. We will explore the different definitions of “stakeholders” and “multi-stakeholders” engagement. This will also be an opportunity to explore some of the benefits, risks and challenges around stakeholder engagement, and explore what are the different types of stakeholders involved in these policies as well as their roles. The workshop will offer an opportunity to: Inform participants about existing physical activity, regulatory and fiscal policies to address childhood obesity;Inform participants about new, innovative EU-level projects that aim to address childhood obesity;Outline preliminary findings of the STOP project with regards to the effectiveness of the evaluated policies;Identify some of the gaps and limitations of existing policies and discuss some of the steps to ensure successful policy implementation. Key messages Present new evidence on what policy approaches work in addressing key determinants of childhood obesity. Showcase findings on the attitudes of different stakeholders towards obesity policies, and debate the benefits, risks and challenges of multi-stakeholder engagement.

scholarly journals Insights in the Role of Lipids, Oxidative Stress and Inflammation in Rheumatoid Arthritis Unveiled by New Trends in Lipidomic Investigations

Antioxidants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 45
Author(s):  
Helena Beatriz Ferreira ◽  
Tânia Melo ◽  
Artur Paiva ◽  
Maria do Rosário Domingues
Keyword(s):  
Rheumatoid Arthritis ◽  
Oxidative Stress ◽  
Lipid Peroxidation ◽  
Lipid Profile ◽  
Inflammatory Responses ◽  
Molecular Level ◽  
Lipid Hydroperoxides ◽  
Lipid Species ◽  
Inflammatory Autoimmune Disease

Rheumatoid arthritis (RA) is a highly debilitating chronic inflammatory autoimmune disease most prevalent in women. The true etiology of this disease is complex, multifactorial, and is yet to be completely elucidated. However, oxidative stress and lipid peroxidation are associated with the development and pathogenesis of RA. In this case, oxidative damage biomarkers have been found to be significantly higher in RA patients, associated with the oxidation of biomolecules and the stimulation of inflammatory responses. Lipid peroxidation is one of the major consequences of oxidative stress, with the formation of deleterious lipid hydroperoxides and electrophilic reactive lipid species. Additionally, changes in the lipoprotein profile seem to be common in RA, contributing to cardiovascular diseases and a chronic inflammatory environment. Nevertheless, changes in the lipid profile at a molecular level in RA are still poorly understood. Therefore, the goal of this review was to gather all the information regarding lipid alterations in RA analyzed by mass spectrometry. Studies on the variation of lipid profile in RA using lipidomics showed that fatty acid and phospholipid metabolisms, especially in phosphatidylcholine and phosphatidylethanolamine, are affected in this disease. These promising results could lead to the discovery of new diagnostic lipid biomarkers for early diagnosis of RA and targets for personalized medicine.

scholarly journals Sex-Specific Differences in Glioblastoma

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1783
Author(s):  
Anna Carrano ◽  
Juan Jose Juarez ◽  
Diego Incontri ◽  
Antonio Ibarra ◽  
Hugo Guerrero Cazares
Keyword(s):  
Sex Differences ◽  
Immune System ◽  
Molecular Level ◽  
Deep Understanding ◽  
Protective Role ◽  
Men And Women ◽  
Individualized Approach ◽  
Male Patients ◽  
Outcome Differences

Sex differences have been well identified in many brain tumors. Even though glioblastoma (GBM) is the most common primary malignant brain tumor in adults and has the worst outcome, well-established differences between men and women are limited to incidence and outcome. Little is known about sex differences in GBM at the disease phenotype and genetical/molecular level. This review focuses on a deep understanding of the pathophysiology of GBM, including hormones, metabolic pathways, the immune system, and molecular changes, along with differences between men and women and how these dimorphisms affect disease outcome. The information analyzed in this review shows a greater incidence and worse outcome in male patients with GBM compared with female patients. We highlight the protective role of estrogen and the upregulation of androgen receptors and testosterone having detrimental effects on GBM. Moreover, hormones and the immune system work in synergy to directly affect the GBM microenvironment. Genetic and molecular differences have also recently been identified. Specific genes and molecular pathways, either upregulated or downregulated depending on sex, could potentially directly dictate GBM outcome differences. It appears that sexual dimorphism in GBM affects patient outcome and requires an individualized approach to management considering the sex of the patient, especially in relation to differences at the molecular level.

In situ nanoscale visualization of solvent effects on molecular crystal surfaces

CrystEngComm ◽  
2021 ◽  
Author(s):  
Mikkel Herzberg ◽  
Anders Støttrup Larsen ◽  
Tue Hassenkam ◽  
Anders Østergaard Madsen ◽  
Jukka Rantanen
Keyword(s):  
Solid Solution ◽  
Solvent Effects ◽  
Molecular Crystal ◽  
Rational Design ◽  
Molecular Level ◽  
Molecular Crystals ◽  
Crystal Surfaces ◽  
Solution Interface ◽  
Atomic Force

Solvents can dramatically affect molecular crystals. Obtaining favorable properties for these crystals requires rational design based on molecular level understanding of the solid-solution interface. Here we show how atomic force...

scholarly journals Erythrocytes: Central Actors in Multiple Scenes of Atherosclerosis

2021 ◽  
Vol 22 (11) ◽  
pp. 5843
Author(s):  
Chloé Turpin ◽  
Aurélie Catan ◽  
Olivier Meilhac ◽  
Emmanuel Bourdon ◽  
François Canonne-Hergaux ◽  
...  
Keyword(s):  
Iron Homeostasis ◽  
The Body ◽  
Diabetic Patients ◽  
Special Focus ◽  
Plaque Progression ◽  
Cell Dysfunction ◽  
Circulating Cells ◽  
The Impact ◽  
Progression Of Atherosclerosis

The development and progression of atherosclerosis (ATH) involves lipid accumulation, oxidative stress and both vascular and blood cell dysfunction. Erythrocytes, the main circulating cells in the body, exert determinant roles in the gas transport between tissues. Erythrocytes have long been considered as simple bystanders in cardiovascular diseases, including ATH. This review highlights recent knowledge concerning the role of erythrocytes being more than just passive gas carriers, as potent contributors to atherosclerotic plaque progression. Erythrocyte physiology and ATH pathology is first described. Then, a specific chapter delineates the numerous links between erythrocytes and atherogenesis. In particular, we discuss the impact of extravasated erythrocytes in plaque iron homeostasis with potential pathological consequences. Hyperglycaemia is recognised as a significant aggravating contributor to the development of ATH. Then, a special focus is made on glycoxidative modifications of erythrocytes and their role in ATH. This chapter includes recent data proposing glycoxidised erythrocytes as putative contributors to enhanced atherothrombosis in diabetic patients.

scholarly journals Foam Cells as Therapeutic Targets in Atherosclerosis with a Focus on the Regulatory Roles of Non-Coding RNAs

2021 ◽  
Vol 22 (5) ◽  
pp. 2529
Author(s):  
Amin Javadifar ◽  
Sahar Rastgoo ◽  
Maciej Banach ◽  
Tannaz Jamialahmadi ◽  
Thomas P. Johnston ◽  
...  
Keyword(s):  
Lipid Metabolism ◽  
Foam Cell ◽  
Cell Formation ◽  
Foam Cells ◽  
Foam Cell Formation ◽  
Special Focus ◽  
Lipid Uptake ◽  
Therapeutic Goals ◽  
Expression Of Genes

Atherosclerosis is a major cause of human cardiovascular disease, which is the leading cause of mortality around the world. Various physiological and pathological processes are involved, including chronic inflammation, dysregulation of lipid metabolism, development of an environment characterized by oxidative stress and improper immune responses. Accordingly, the expansion of novel targets for the treatment of atherosclerosis is necessary. In this study, we focus on the role of foam cells in the development of atherosclerosis. The specific therapeutic goals associated with each stage in the formation of foam cells and the development of atherosclerosis will be considered. Processing and metabolism of cholesterol in the macrophage is one of the main steps in foam cell formation. Cholesterol processing involves lipid uptake, cholesterol esterification and cholesterol efflux, which ultimately leads to cholesterol equilibrium in the macrophage. Recently, many preclinical studies have appeared concerning the role of non-encoding RNAs in the formation of atherosclerotic lesions. Non-encoding RNAs, especially microRNAs, are considered regulators of lipid metabolism by affecting the expression of genes involved in the uptake (e.g., CD36 and LOX1) esterification (ACAT1) and efflux (ABCA1, ABCG1) of cholesterol. They are also able to regulate inflammatory pathways, produce cytokines and mediate foam cell apoptosis. We have reviewed important preclinical evidence of their therapeutic targeting in atherosclerosis, with a special focus on foam cell formation.

scholarly journals Transnational Lived Citizenship – The Case of the Eritrean Diaspora

2021 ◽  
Vol 56 (1) ◽  
pp. 3-18
Author(s):  
Tanja R. Müller ◽  
Milena Belloni
Keyword(s):  
The State ◽  
Special Focus ◽  
Diaspora Studies ◽  
Historical Events ◽  
Everyday Practices ◽  
Key Questions

This special focus section analyses state–diaspora relationships with a focus on the case of Eritrea, a paradigmatic example, as we show in this introduction, to elaborate on the following key questions: What determines loyalty between diaspora and the state? How can we understand the dynamics of co-optation, loyalty, and resistance that characterise many diaspora–state relationships? What is the role of historical events and memory in building alliances as well as divides among different generations and different groups in the diaspora? How do diaspora citizens interpret and enact their citizenship in everyday practices of engagement? By engaging with both citizenship and diaspora studies, this introduction shows the significance of analysing these questions through the lens of “transnational lived citizenship.” This concept enables a look at the intersections between formal aspects of citizenship as well as the emotional and practical aspects related to feelings of belonging, transnational attitudes, and circulation of material cultures.

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