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Insulin resistance: Risk factors, diagnostic approaches and mathematical models for clinical practice, epidemiological studies, and beyond

Krzymien Janusz, Ladyzynski Piotr

Biocybernetics and Biomedical Engineering

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2024

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Vol. 44, no. 1

55--67

EN

Insulin resistance (IR) is a multifactorial metabolic disorder associated with the development of cardiometabolic syndrome, cardiovascular diseases and obesity. Factors such as inflammation, hyperinsulinemia, hyperglucagonemia, mitochondrial dysfunction, glucotoxicity and lipotoxicity contribute to the development of IR. Despite being extensively studied for over 60 years, assessing the incidence of IR, developing effective prevention strategies, and implementing appropriate therapeutic approaches remain challenging. This review explores the multifaceted nature of IR, including its association with various conditions such as obesity, primary hypertension, dyslipidemia, obstructive sleep apnea, Alzheimer’s disease, non-alcoholic fatty liver disease, polycystic ovary syndrome, chronic kidney disease and cancer. Additionally, we discuss the complexity of diagnosing and quantifying IR, emphasizing the lack of absolute, common criteria for classification. We delve into the use of mathematical models in clinical and epidemiological studies, focusing on the choice between insulin, triglycerides, or waist-to-hip ratio as IR determinants. Furthermore, we highlight the importance of reliable input data and caution in interpreting results when utilizing mathematical models for IR assessment. This narrative review aims to provide insights into the challenges and considerations involved in conducting IR diagnostics, with implications for clinical practice, epidemiological research, and future advancements in this field.

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O zależnościach pomiędzy aromatycznością i efektem podstawnikowym w układach jednopierścieniowych

Szatyłowicz Halina, Krygowski Tadeusz Marek

Wiadomości Chemiczne

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2019

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[Z] 73, 3-4

243--261

EN

Aromaticity/aromatic and substituent/substituent effects belong to the most commonly used terms in organic chemistry and related fields. They are used for more than a century, and so far are the subject of thousands publications a year. The quantitative description of the aromaticity of planar π-electron cyclic molecules is based on four criteria: (i) they are more stable than their acyclic unsaturated analogues, (ii) bonds have intermediate lengths between those for the single and double ones, (iii) external magnetic field induces π-electron ring current, and (iv) aromatic systems prefer reactions in which the π-electron structure is preserved. conserved. Quantitative characteristics based on these criteria, named as aromaticity indices, allow to relate aromaticity to the substituent effect. This latter can be described using either traditional Hammett-type substituent constants or characteristics based on quantum-chemistry. For this purpose, the energies of properly designed homodesmotic reactions and electron density distribution are used. In the first case, a descriptor named SESE (substituent effect stabilization energy) is obtained, while in the second case – cSAR (charge of the substituent active region), which is the sum of the charge of the ipso carbon atom and the charge of the substituent. The application of these substituent effect descriptors to a set of π-electron systems, such as: benzene, quinones, cyclopenta- and cyclohepta-dienes, as well as some azoles, allowed to draw the following conclusions: (i) The less aromatic the system, the stronger the substituent influences the π-electron system. Highly aromatic systems are resistant to the substituent effect, in line with the organic chemistry experience that aromatic compounds dislike reactions leading to changes in the π-electron structure of the ring. (ii) Intramolecular charge transfer (resonance effect) is privileged in cases where the number of bonds between the electron-attracting and electron-donating atoms is even. These effects are much weaker when this number is odd. Classically, it may be related to traditional para vs meta substituent effects in benzene derivatives. We should note that in electron-accepting groups, such as CN or NO2 (and others), electron-accepting atoms are second counting from Cipso. (iii) In all cases, when the substituent changes number of π-electrons in the ring in the direction of 4N+2, its aromaticity increases, for example electron-donating substituents in exocyclic substituted pentafulvene, or a halogen atom in complexes with heptafulvene.

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Strukturalne i elektronowe aspekty wiązania azot–azot

Gajda K., Zarychta B., Ejsmont K.

Chemik

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2014

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Vol. 68, nr 4

363--368

PL

Azot, podobnie jak wiele innych pierwiastków chemicznych, posiada zdolność do katenacji. Największą grupę związków z układami Nx stanowią te, które zawierają dwa atomy azotu, a najliczniejszą wśród nich a najliczniejsze wśród nich to związki –hydrazo, –azo, –azoksy, –azodioksy oraz związki zawierające grupę nitraminową. W prezentowanych badaniach dla ustalenia zmian w długości wiązania azot–azot wyliczono średnie jej wartości na podstawie obliczeń kwantowo-mechanicznych oraz danych z krystalograficznej bazy CSD. Dodatkowo, przy użyciu indeksu aromatyczności HOMA opartego na kryteriach geometrycznyche, wyliczono aromatyczność pierścieni fenylowych związanych z analizowanymi grupami funkcyjnymi.

EN

Nitrogen, like many other chemical elements, has catenation ability. The largest family of compounds containing Nx systems are compounds containing two nitrogen atoms, and the most numerous among them are hydrazo, azo, azoxy, azodioxy compounds and compounds with nitramine group. In the presented studies for determining changes in nitrogennitrogen bond length, average lengths were calculated based on quantum mechanical calculations and data from crystallographic database CSD. Furthermore, the aromaticity of phenyl rings connected to studied functional groups was calculated using HOMA aromaticity index based on geometric criteria.

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Five-Membered Heterocycles. Part V. Impact of Heteroatoms on Aromaticity of Five-Membered Heterocycles

Mrozek A., Karolak-Wojciechowska J.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 5-6

721-730

EN

The aromaticity (in the form ofHOMAindex) of various five-membered heterorings systems and their bicyclic derivatives containing N, S, O, and P were studied on the basis of statistical data from Cambridge Structural Database (CSD). The calculations of HOMA were done for pyrroles, furans, thiophenes, phospholes, imidazoles, oxazoles, thiazoles, phosphazoles as well as for 6 + 5 fused systems: benzimidazoles, benzoxazoles, benzothiazoles, and benzophosphazoles. Detailed analysis showed that relationship between classical aromaticity and electronegativity of heteroatom is described by squared equation. An optimal value of electronegativity is about 2.9 (Pauling’s scale) for which aromaticity of heterorings reaches the highest level. For fused systems, the presence of benzene ring causes the evident increasing of average value of HOMA indices.