scholarly journals Redox Chemistry and [Au(CN)2-] in the Formation of Gold Metabolites

1994 ◽  
Vol 1 (5-6) ◽  
pp. 351-362 ◽  
Author(s):  
G. Frank Shaw III ◽  
Sabine Schraa ◽  
Ernst Gleichmann ◽  
Yash Paul Grover ◽  
Lothar Dunemann ◽  
...  
Keyword(s):  
Ligand Exchange ◽  
Strong Association ◽  
Enzymatic Reaction ◽  
Phosphine Ligands ◽  
Initial Oxidation ◽  
Full Extent ◽  
Gold Thioglucose ◽  
Pharmacological Significance ◽  
Rate Of Reaction

The role of hypochlorite ion, which can be generated by the enzyme myleoperoxidase, in the biochemistry of gold(I) anti-arthritic drugs was investigated. Sodium hypochlorite (OCl−) directly and rapidly oxidizes AuSTm, Au(CN)2-, AuSTg (gold thioglucose) and auranofin (Et3PAuSATg). The resulting gold(III) species were detected by an Ion Chromotography Ion-Pairing technique that was developed to distinguish gold(I) and gold(III). Formation of Au(III) was also demonstrated spectrophotometrically after the conversion to AuCl4−. The reactions of AuSTm, AuSTg, and auranofin are complex and gold(III) appears only after the initial oxidation of the thiolate (and phosphine) ligands.The enzymatic reaction, using MPO with H2O2 and Cl− as substrates, leads to slow oxidation of Au(CN)2-, AuSTm or AuSTg. The extent and rate of reaction depend on the concentrations of MPO, H2O2, and Au(I). The continued presence of Au(I) during the initial stages of reaction (oxidation of the thiolates in AuSTm and AuSTg) and the conversion to Au(III) in the latter stages of the reaction were demonstrated.Au(CN)2-, a gold metabolite, binds tightly to serum albumin. Unlike other gold(I) complexes, aurocyanide reacts almost negligibly at Cys-34 via ligand exchange. Instead, there is a strong association (K1 = 5.5 × 104 and K2 = 7.0 × 103; n1 = 0.8 and n2 = 3) of intact Au(CN)2-. The full extent of binding is revealed only by equilibrium methods such as NMR or ultrafiltration; the bound gold dissociates extensively on conventional gel-exclusion columns and partially on Penefesky spun columns.The immunological and pharmacological significance of these results are discussed.

scholarly journals Uric Acid and Hypertension: Prognostic Role and Guide for Treatment

2021 ◽  
Vol 10 (3) ◽  
pp. 448
Author(s):  
Federica Piani ◽  
Arrigo F. G. Cicero ◽  
Claudio Borghi
Keyword(s):  
Clinical Trials ◽  
Uric Acid ◽  
Mendelian Randomization ◽  
Strong Association ◽  
Epidemiological Studies ◽  
Hypertensive Disease ◽  
Genetic Studies ◽  
Lowering Therapy ◽  
The Relationship

The relationship between serum uric acid (SUA) and hypertension has been a subject of increasing interest since the 1870 discovery by Frederick Akbar Mahomed. Several epidemiological studies have shown a strong association between high SUA levels and the presence or the development of hypertension. Genetic analyses have found that xanthine oxidoreductase (XOR) genetic polymorphisms are associated with hypertension. However, genetic studies on urate transporters and Mendelian randomization studies failed to demonstrate a causal relationship between SUA and hypertension. Results from clinical trials on the role of urate-lowering therapy in the management of patients with hypertension are not uniform. Our study sought to analyze the prognostic and therapeutic role of SUA in the hypertensive disease, from uric acid (UA) biology to clinical trials on urate-lowering therapies.

A first-principles study of the atomic layer deposition of ZnO on carboxyl functionalized carbon nanotubes: the role of water molecules

2021 ◽  
Vol 23 (5) ◽  
pp. 3467-3478
Author(s):  
J. I. Paez-Ornelas ◽  
H. N. Fernández-Escamilla ◽  
H. A. Borbón-Nuñez ◽  
H. Tiznado ◽  
Noboru Takeuchi ◽  
...  
Keyword(s):  
First Principles ◽  
Ligand Exchange ◽  
Functional Group ◽  
Atomic Layer ◽  
High Reactivity ◽  
Water Molecules ◽  
Exchange Reactions ◽  
Layer Deposition ◽  
The Right

Atomic description of ALD in systems that combine large surface area and high reactivity is key for selecting the right functional group to enhance the ligand-exchange reactions.

The role of dynamics in modulating ligand exchange in intracellular lipid binding proteins

2014 ◽  
Vol 1844 (7) ◽  
pp. 1268-1278 ◽  
Author(s):  
Laura Ragona ◽  
Katiuscia Pagano ◽  
Simona Tomaselli ◽  
Filippo Favretto ◽  
Alberto Ceccon ◽  
...  
Keyword(s):  
Ligand Exchange ◽  
Binding Proteins ◽  
Lipid Binding ◽  
Intracellular Lipid ◽  
Lipid Binding Proteins

scholarly journals “Snow Scenes”: Exploring the Role of Memory and Place in Commemorating Extreme Winters

2016 ◽  
Vol 8 (1) ◽  
pp. 5-19 ◽  
Author(s):  
Alexander Hall ◽  
Georgina Endfield
Keyword(s):  
Rural Communities ◽  
Local Level ◽  
Strong Association ◽  
Potential Effect ◽  
Cultural Dimensions ◽  
Extreme Weather Events ◽  
National Narratives ◽  
Local Climate ◽  
Weather Events

Abstract Scholars are increasingly focusing on the cultural dimensions of climate, addressing how individuals construct their understanding of climate through local weather. Research often focuses on the importance of widespread conceptualizations of mundane everyday weather, although attention has also been paid to extreme weather events and their potential effect on popular understandings of local climate. This paper introduces the “Snow Scenes” project, which aimed to engage rural communities in Cumbria, England, with their memories of extreme and severe past winter conditions in the region. Collating memories across a wide demographic, using a variety of methods, individual memories were analyzed alongside meteorological and historical records. By exploring these memories and their associated artifacts, this paper aims to better understand the role of memory and place in commemorating extreme winters. First, it is demonstrated how national narratives of exceptional winters are used by individuals as benchmarks against which to gauge conditions. Second, this paper identifies how specific locations and landmarks help to place memories and are shown to be important anchors for individuals’ understanding of their climate. Third, the paper considers how memories of severe winters are often nostalgic in their outlook, with a strong association between snowy winters, childhood, and childhood places. Fourth, it is illustrated how such events are regularly connected to important personal or familial milestones. Finally, the paper reflects on how these local-level experiences of historical extreme events may be central to the shaping of popular understandings of climate and also, by extension, climate change.

Looking into a New Challenge, DKA and Covid-19 A Review on Pediatric DKA Cases during New Coronavirus Pandemic Who is to Blame, the Virus or Health System?

2021 ◽  
Vol 5 (7) ◽  
pp. 01-04
Author(s):  
Vida Tajiknia ◽  
Maryam Ghandali ◽  
Ardavan Ahmadvand ◽  
Ali Afrasiabi ◽  
Reza Pirdehghan ◽  
...  
Keyword(s):  
Immune System ◽  
Virus Infection ◽  
Pediatric Patients ◽  
Strong Association ◽  
Diabetes Type ◽  
Diabetes Type 1 ◽  
The World ◽  
Existing Data

Since the first month of this new pandemic situation, all around the world healthcare system has been facing different challenges and difficulties; patients with chronic diseases such as cancer or diabetes with impaired immune system were at greater risk of infections and complications. It goes without saying that this issue was extremely important among pediatric clinicians dealing with diabetic pediatrics. Diabetes is the number one chronic illness among pediatric patients and the most dangerous and frightened complication of it is Diabetic Ketoacidosis (DKA). Studies have shown a strong association between pandemic and increase in new diabetes type 1 cases and its lethal complication called DKA. Here we are going to take a look at existing data and report about cases with this condition trying to find the missing piece of a big puzzle; what is the role of Covid-19 in causing Diabetes in previously healthy kids and what is the real association between SARS-COV2 virus infection and DKA? We are going to review different studies, possible mechanism, new t1dm cases and old cases, with or without covid infection, DKA cases and its severity.

Radical Mechanisms in Saturated and Olefinic Systems. II. Disubstitutive Carbon-Carbon Cross-Linking by Tertiary Alkoxy Radicals in Isoprenic Olefins and Rubber

1951 ◽  
Vol 24 (4) ◽  
pp. 777-786
Author(s):  
E. H. Farmer ◽  
C. G. Moore
Keyword(s):  
Natural Rubber ◽  
Cross Linking ◽  
Chain Molecules ◽  
Alkoxy Radicals ◽  
Full Extent ◽  
Carbon Chains ◽  
Butyl Peroxide ◽  
High Degree ◽  
Vulcanization Process

Abstract The high degree of dehydrogenation effected by tert.-butoxy radicals at the α-methylenic groups of olefins enables these radicals to be used for the carbon-to-carbon cross-linking of unsaturated carbon chains, and especially of the polyisoprenic chains of natural rubber. Such cross-linking amounts to a vulcanization process in which the connecting links between chain molecules are just C—C bonds, which may be expected to have appropriate attributes. An examination has first been made of the cross-linking produced by tert.- butoxy radicals (from di-tert.-butyl peroxide) at 140° between the short iso-prenic chains in 1-methylcyclohexene, 4-methylhept-3-ene, 2,6-dimethylocta-2, 6-diene, and digeranyl. Cross-linking proceeds efficiently in each case, and the points of union in these isoprene units which become directly joined are not confined to original α-methylenic carbon atoms. Where the reagent radicals are in considerable deficit, e.g., one per two or three of the isoprene units present, those olefin molecules which are attacked become linked together mostly by single unions to form aggregates containing two, three or four molecules; but in the tetraisoprenic olefins the extent to which more than one union is formed between some of the directly linked molecules becomes appreciable. In natural rubber, cross-linking occurs smoothly and to nearly the full extent corresponding to the (in practice restricted) proportion of peroxidic reagent employed. Good vulcanizates can be so obtained in which the tensile stength is found to increase towards a maximum and then to decline rapidly as the degree of cross-linking steadily increases. Thus to obtain vulcanizates of the optimum physical characteristics, the degree of cross-linking must be suitably chosen. The role of the peroxidic reagent is almost entirely non-additive and non-degradative.

scholarly journals Mouthrinses containing alcohol and oral cancer: revision of epidemiological studies

2007 ◽  
Vol 21 (spe) ◽  
pp. 16-22 ◽  
Author(s):  
Silvia Adriana López de Blanc ◽  
Ana María Baruzzi
Keyword(s):  
Oral Cancer ◽  
Strong Association ◽  
Epidemiological Studies ◽  
Clear Relationship

The strong association between alcohol usage and the development of oral cancer (OC) has been reported in numerous papers. As some mouthrinses contain significant amounts of ethanol, a possible relationship to this pathology has been considered. The purpose of the present paper is to analyze several epidemiological studies which evaluated the association between commercial mouthrinses and the etiology of OC. Although some authors report an association, most of the studies are unclear and sometimes contradictory. The controversial aspects regarding the role of alcohol in OC may also make difficult to find a clear relationship between the use of mouthrinses containing alcohol and OC.

scholarly journals Association between spectator and other roles in school bullying

2016 ◽  
Vol 26 (3) ◽  
pp. 352
Author(s):  
Marcela Almeida Zequinão ◽  
Pâmella De Medeiros ◽  
Beatriz Pereira ◽  
Fernando Luiz Cardoso
Keyword(s):  
Public Schools ◽  
Negative Reinforcement ◽  
Strong Association ◽  
School Bullying ◽  
The Other ◽  
Seventh Grade ◽  
Santa Catarina ◽  
The Third ◽  
Aggressive Behaviours

Introduction: The school bullying is characterized by repetitiveness of aggression and the intentionality to injure or cause suffering to others. The bystanders to this phenomenon tend to be mainly responsible for the course that bullying will take and its results. Objective: To analyse the association between the role of bystander with the other possible roles played in bullying. Method: A total of 409 children from the third to seventh grade participated in this study, with an average age of 11 years (SD = 1.61), enrolled in two municipal public schools in Florianópolis, Santa Catarina, Brazil. The instruments used were: one of the scales of the Questionnaire for the Study of Violence Among Peers, to identify bystanders, and the Olweus Questionnaire, to describe the possible roles played in school bullying. Results: It was found that most of the participants assumed the role of bystander in school bullying. However, an association was found with regard to gender and being a bystander. Also, strong association was found between being a bystander and the other roles played in bullying, primarily in relation to the bullies. Conclusion: These results reinforce the importance of bystanders in these aggressions, not only because they represent most of the participants, but mainly because of the positive or negative reinforcement they can offer in these aggressive behaviours. Therefore, the incentive and the encouragement of these students to denounce the aggressors, as well as defending the victims is essential to reduce school bullying.

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