Charge distributions and chemical effects. XIX. Analysis of 'bonded' and 'non-bonded' energy contributions in saturated hydrocarbons

1979 ◽  
Vol 57 (14) ◽  
pp. 1772-1778 ◽  
Author(s):  
Sándor Fliszár ◽  
Marie-Thérèse Béraldin
Keyword(s):  
Structural Changes ◽  
Structural Features ◽  
Chemical Bonds ◽  
Coulomb Interactions ◽  
Structural Effects ◽  
Saturated Hydrocarbons ◽  
Polycyclic Hydrocarbons ◽  
Charge Distributions ◽  
Chemical Effects ◽  
Prime Factors

Total Coulomb interactions between non-bonded atoms behave in general in a 'quasi-additive' fashion, not only in simple linear and branched paraffins, but also in polycyclic hydrocarbons constructed from chair and boat cyclohexane rings. Because of their relative insensitivity to structural features, they cannot be regarded as being the leading terms in the explanation of energetic effects related to structural changes. The prime factors governing molecular stabilities, as well as the explanation of the structural effects which are at their origin, are found in the behavior of the charge dependent energy contributions associated with bonded atoms, i.e., in the chemical bonds themselves.

scholarly journals Interaction of Lactoferrin with Unsaturated Fatty Acids: In Vitro and In Vivo Study of Human Lactoferrin/Oleic Acid Complex Cytotoxicity

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1602
Author(s):  
Anna Elizarova ◽  
Alexey Sokolov ◽  
Valeria Kostevich ◽  
Ekaterina Kisseleva ◽  
Evgeny Zelenskiy ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Structural Changes ◽  
Unsaturated Fatty Acids ◽  
Structural Features ◽  
Control Group ◽  
Acid Complex ◽  
Hepatoma 22A ◽  
Constitutive Parameters

As shown recently, oleic acid (OA) in complex with lactoferrin (LF) causes the death of cancer cells, but no mechanism(s) of that toxicity have been disclosed. In this study, constitutive parameters of the antitumor effect of LF/OA complex were explored. Complex LF/OA was prepared by titrating recombinant human LF with OA. Spectral analysis was used to assess possible structural changes of LF within its complex with OA. Structural features of apo-LF did not change within the complex LF:OA = 1:8, which was toxic for hepatoma 22a cells. Cytotoxicity of the complex LF:OA = 1:8 was tested in cultured hepatoma 22a cells and in fresh erythrocytes. Its anticancer activity was tested in mice carrying hepatoma 22a. In mice injected daily with LF-8OA, the same tumor grew significantly slower. In 20% of animals, the tumors completely resolved. LF alone was less efficient, i.e., the tumor growth index was 0.14 for LF-8OA and 0.63 for LF as compared with 1.0 in the control animals. The results of testing from 48 days after the tumor inoculation showed that the survival rate among LF-8OA-treated animals was 70%, contrary to 0% rate in the control group and among the LF-treated mice. Our data allow us to regard the complex of LF and OA as a promising tool for cancer treatment.

scholarly journals Post-operative rehabilitation and nutrition in osteoarthritis

F1000Research ◽  
2016 ◽  
Vol 3 ◽  
pp. 116 ◽  
Author(s):  
Giuseppe Musumeci ◽  
Ali Mobasheri ◽  
Francesca Maria Trovato ◽  
Marta Anna Szychlinska ◽  
Rosa Imbesi ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
Physical Exercise ◽  
Structural Changes ◽  
Exercise Program ◽  
Structural Features ◽  
Synovial Joint ◽  
Comprehensive Overview ◽  
Postoperative Rehabilitation ◽  
Keywords Osteoarthritis ◽  
Rehabilitation Exercise

Osteoarthritis (OA) is a degenerative process involving the progressive loss of articular cartilage, synovial inflammation and structural changes in subchondral bone that lead to loss of synovial joint structural features and functionality of articular cartilage. OA represents one of the most common causes of physical disability in the world. Different OA treatments are usually considered in relation to the stage of the disease. In the early stages, it is possible to recommend physical activity programs that can maintain joint health and keep the patient mobile, as recommended by OA Research Society International (OARSI) and European League Against Rheumatism (EULAR). In the most severe and advanced cases of OA, surgical intervention is necessary. After, in early postoperative stages, it is essential to include a rehabilitation exercise program in order to restore the full function of the involved joint. Physical therapy is crucial for the success of any surgical procedure and can promote recovery of muscle strength, range of motion, coordinated walking, proprioception and mitigate joint pain. Furthermore, after discharge from the hospital, patients should continue the rehabilitation exercise program at home associated to an appropriate diet. In this review, we analyze manuscripts from the most recent literature and provide a balanced and comprehensive overview of the latest developments on the effect of physical exercise on postoperative rehabilitation in OA. The literature search was conducted using PubMed, Scopus, Web of Science and Google Scholar, using the keywords ‘osteoarthritis’, ‘rehabilitation’, ‘exercise’ and ‘nutrition’. The available data suggest that physical exercise is an effective, economical and accessible to everyone practice, and it is one of the most important components of postoperative rehabilitation for OA.

Charge distributions and chemical effects

1980 ◽  
Vol 68 ◽  
pp. 227-234 ◽  
Author(s):  
A.E. Foti ◽  
V.H. Smith ◽  
S. Fliszár
Keyword(s):  
Charge Distributions ◽  
Chemical Effects

scholarly journals Century-Long Dynamics of the Land Use Structure in the United States

2020 ◽  
pp. 220-231
Author(s):  
Valerij Minat
Keyword(s):  
United States ◽  
Land Use ◽  
Structural Changes ◽  
The United States ◽  
Structural Features ◽  
Summary Table ◽  
Land Use Structure ◽  
Periodic Dynamics ◽  
Space Dynamics ◽  
American Society

The paper studies the experience of American land use in the twentieth century on the territory of 48 contiguous continental states. Changes in time and space (dynamics) of the main indicators of distribution and use of land resources that form the structural appearance of the U.S. land fund are shown. Based on the analysis of the countrys land use structure, the resulting part of which is a summary table, the periodic dynamics of the land use structure (in twenty-year time intervals) is considered, and the dependence of structural changes in land use on the level and nature of the socio-economic development of American society is shown. The study of the age-old dynamics of structural features of American land use conducted on the basis of scientific materials of American scientists and data from official American statistics makes it possible to draw generalizing conclusions about the nature of land use in the United States, both in the whole country and in the regional aspect. As a result, the author has obtained a generalized scientific picture of how the structure of land use in the continental part of the country (without Alaska) has changed over the course of a century in the direction from maximum to optimal use of natural resources.

scholarly journals Structural Characterization and Antioxidant Activity of Milled Wood Lignin from Xylose Residue and Corncob

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2092 ◽  
Author(s):  
Miaomiao Xu ◽  
Chao Wang ◽  
Gaojin Lyu ◽  
Lei Zhong ◽  
Liyuan Yang ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Structural Changes ◽  
Food Additives ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Gel Permeation Chromatography ◽  
Structural Features ◽  
2D Nmr Spectroscopy ◽  
Milled Wood Lignin ◽  
Xylose Residue

Xylose residue (XR), after diluted acid treatment of corncob, consists of cellulose and lignin. However, structural changes of XR lignin have not been investigated comprehensively, and this has seriously hindered the efficient utilization of lignin. In this study, corncob milled wood lignin (CC MWL), and xylose residue milled wood lignin (XR MWL) were isolated according to the modified milled wood lignin (MWL) method. The structural features of two lignin fractions were thoroughly investigated via fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), thermogravimetric analysis (TGA) and two dimensional nuclear magnetic resonance (2D NMR) spectroscopy techniques. XR MWL with higher yield and lower bound carbohydrate contents presented more phenolic OH contents than CC MWL due to partial cleavage of β-O-4. Furthermore, the molecular weights of XR MWL were increased, possibly because of condensation of the lignin during the xylose production. A study on antioxidant activity showed that XR lignin had better radical scavenging ability than that of 2,6-Di-tert-butyl-4-methyl-phenol (BHT) and CC MWL. The results suggested that the lignin in xylose residue, showing great antioxidant properties, has potential applications in food additives.

scholarly journals Crosslinked Recombinant-Ara h 1 Catalyzed by Microbial Transglutaminase: Preparation, Structural Characterization and Allergic Assessment

Foods ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1508
Author(s):  
Yang Tian ◽  
Chenglong Liu ◽  
Wentong Xue ◽  
Zhongfu Wang
Keyword(s):  
Disulfide Bonds ◽  
Structural Changes ◽  
Structural Features ◽  
Microbial Transglutaminase ◽  
Enzyme Linked Immunosorbent Assay ◽  
Cross Linking ◽  
Intrinsic Structure ◽  
Ara H 1 ◽  
Molecular Forces ◽  
The One

As the one of the major allergens in peanut, the allergenicity of Ara h 1 is influenced by its intrinsic structure, which can be modified by different processing. However, molecular information in this modification has not been clarified to date. Here, we detected the influence of microbial transglutaminase (MTG) catalyzed cross-linking on the recombinant peanut protein Ara h 1 (rAra h 1). Electrophoresis and spectroscopic methods were used to analysis the structural changes. The immunoreactivity alterations were characterized by enzyme linked immunosorbent assay (ELISA), immunoblotting and degranulation test. Structural features of cross-linked rAra h 1 varied at different reaction stages. Hydrogen bonds and disulfide bonds were the main molecular forces in polymers induced by heating and reducing. In MTG-catalyzed cross-linking, ε-(γ-glutamyl) lysine isopeptide bonds were formed, thus inducing a relatively stable structure in polymers. MTG catalyzed cross-linking could modestly but significantly reduce the immunoreactivity of rAra h 1. Decreased content of conserved secondary structures led to a loss of protection of linear epitopes. Besides, the reduced surface hydrophobic index and increased steric hindrance of rAra h 1 made it more difficult to bind with antibodies, thus hindering the subsequent allergic reaction.

Sputtered Fitas of Amorphous Hydrogenated Silicon Carbide

1987 ◽  
Vol 97 ◽  
Author(s):  
Richard B. Rizk ◽  
Alain E. Kaloyeros ◽  
Wendell S. Williams ◽  
Nancy Finnegan ◽  
Carol Kozlowski
Keyword(s):  
Structural Changes ◽  
Rapid Development ◽  
Chemical Bonds ◽  
Complete Understanding ◽  
Silicon Matrix ◽  
Hydrogenated Silicon ◽  
Physical Mechanisms ◽  
Amorphous Hydrogenated Silicon ◽  
Silicon Carbon ◽  
Scientific Attention

The field of amorphous hydrogenated silicon-carbon alloys and thin films has witnessed, since the pioneering work of Anderson and Spear [1], rapid development and has attracted scientific attention and technological interest [2,3]. However, relatively little information is known [4] about the physical mechanisms that govern the inclusion of C and H in the silicon matrix, the nature of the chemical bonds involved, and the structural changes that result in the amorphous phase. Clearly, further fundamental studies are needed to achieve complete understanding of such amorphous systems with variable disorder.

scholarly journals Analysis of the structural variability of topologically associated domains as revealed by Hi-C

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Natalie Sauerwald ◽  
Akshat Singhal ◽  
Carl Kingsford
Keyword(s):  
Structural Changes ◽  
Chromosome Structure ◽  
Three Dimensional ◽  
Replication Timing ◽  
Building Blocks ◽  
Structural Features ◽  
Genetic Sequence ◽  
Experimental Variation ◽  
Topologically Associated Domains ◽  
Integral Role

Abstract Three-dimensional chromosome structure plays an integral role in gene expression and regulation, replication timing, and other cellular processes. Topologically associated domains (TADs), building blocks of chromosome structure, are genomic regions with higher contact frequencies within the region than outside the region. A central question is the degree to which TADs are conserved or vary between conditions. We analyze 137 Hi-C samples from 9 studies under 3 measures to quantify the effects of various sources of biological and experimental variation. We observe significant variation in TAD sets between both non-replicate and replicate samples, and provide initial evidence that this variability does not come from genetic sequence differences. The effects of experimental protocol differences are also measured, demonstrating that samples can have protocol-specific structural changes, but that TADs are generally robust to lab-specific differences. This study represents a systematic quantification of key factors influencing comparisons of chromosome structure, suggesting significant variability and the potential for cell-type-specific structural features, which has previously not been systematically explored. The lack of observed influence of heredity and genetic differences on chromosome structure suggests that factors other than the genetic sequence are driving this structure, which plays an important role in human disease and cellular functioning.

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