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Hypertensive disorders of pregnancy (HDP) are a great danger. A previous GWAS found a relationship between rs259983 of the ZNF831 gene and HDP, such as for chronic hypertension (CHTN) and preeclampsia (PE). We conducted the case-control study to determine the association between rs259983 of the ZNF831 gene and HDP in women with Gestational Diabetes Mellitus (GDM). For target genotyping, we developed primers and TaqMan probes. In analyzing the population, we did not manage to find a relationship between PE and rs259983 of the ZNF831 gene. Additional study of women with PE and PE superimposed on CHTN (SIPE) establishes an association between rs259983 of the ZNF831 gene only with SIPE. Carriers of CC genotypes have been discovered to have a 5.05 times higher risk of SIPE development in women with GDM. [ABSTRACT FROM AUTHOR]

The 199Hg chemical-shift tensor of solid HgCl2 was determined from spectra of polycrystalline materials, using static and magic-angle spinning (MAS) techniques at multiple spinning frequencies and field strengths. The chemical-shift tensor of solid HgCl2 is axially symmetric (η = 0) within experimental error. The 199Hg chemical-shift anisotropy (CSA) of HgCl2 in a frozen solution in dimethylsulfoxide (DMSO) is significantly smaller than that of the solid, implying that the local electronic structure in the solid is different from that of the material in solution. The experimental chemical-shift results (solution and solid-state) are compared with those predicted by density functional theory (DFT) calculations using the zeroth-order regular approximation (ZORA) to account for relativistic effects.199Hg spin-lattice relaxation of HgCl2 dissolved in DMSO is dominated by a CSA mechanism, but a second contribution to relaxation arises from ligand exchange. Relaxation in the solid state is independent of temperature, suggesting relaxation by paramagnetic impurities or defects.

Perfluoroalkyl carboxylic and sulfonic acids (PFCAs and PFSAs, respectively) have low acid dissociation constant values and are, therefore, deprotonated under most experimental and environmental conditions. Hence, the anionic species dominate their partitioning between water and organic phases, including octanol and phospholipid bilayers which are often used as model systems for environmental and biological matrices. However, data for solvent–water (SW) and membrane–water partition coefficients of the anion species are only available for a few per‐ and polyfluoroalkyl substances (PFAS). In the present study, an equation is derived using a Born‐Haber cycle that relates the partition coefficients of the anions to those of the corresponding neutral species. It is shown via a thermodynamic analysis that for carboxylic acids (CAs), PFCAs, and PFSAs, the log of the solvent–water partition coefficient of the anion, log KSW(A−), is linearly related to the log of the solvent–water partition coefficient of the neutral acid, log KSW(HA), with a unity slope and a solvent‐dependent but solute‐independent intercept within a PFAS (or CA) family. This finding provides a method for estimating the partition coefficients of PFCAs and PFSAs anions using the partition coefficients of the neutral species, which can be reliably predicted using quantum chemical methods. In addition, we have found that the neutral octanol–water partition coefficient, log KOW, is linearly correlated to the neutral membrane–water partition coefficient, log KMW; therefore, log KOW, being a much easier property to estimate and/or measure, can be used to predict the neutral log KMW. Application of this approach to KOW and KMW for PFCAs and PFSAs demonstrates the utility of this methodology for evaluating reported experimental data and extending anion property data for chain lengths that are unavailable. Environ Toxicol Chem 2023;42:2317–2328. © 2023 SETAC [ABSTRACT FROM AUTHOR]

To successfully understand and model the environmental fate of per- and polyfluoroalkyl substances (PFAS), it is necessary to know key physicochemical properties (PChPs) such as pKa; however, measured PChPs of PFAS are scarce and of uncertain reliability. In this study, quantitative structure–activity relationships (QSARs) were developed by correlating calculated (M062-X/aug-cc-pVDZ) vibrational frequencies (VF) and corresponding infrared intensities (IRInt) to the pKa of carboxylic acids, sulfonic acids, phosphonic acids, sulfonamides, betaines, and alcohols. Antisymmetric stretching VF of the anionic species were used for all subclasses except for alcohols where the OH stretching VF performed better. The individual QSARs predicted the pKa for each subclass mostly within 0.5 pKa units from the experimental values. The inclusion of IRInt as a pKa predictor for carboxylic acids improved the results by decreasing the root-mean-square error from 0.35 to 0.25 (n > 100). Application of the developed QSARs to estimate the pKa of PFAS within each subclass revealed that the length of the perfluoroalkyl chain has minimal effect on the pKa, consistent with other models but in stark contrast with the limited experimental data available. [ABSTRACT FROM AUTHOR]

One of the most significant factors for age-related macular degeneration (AMD) development is considered to be aging, the processes of which are closely associated with telomere shortening. The different forms, indicators of aggressiveness, and intensities of AMD can be observed in the same age group, confirming the need to find a biomarker for early diagnosis and be capable of monitoring the progression of the pathological process. Therefore, we investigated whether the relative telomere length (RTL) has any connection with the risk of development of disease and its progression. RTL was measured using RT-PCR in 166 people, including 96 patients with AMD. RTL was significantly lower in patients with AMD. Women were more likely to develop AMD than men (odds ratio (OR) = 9.53 × 106 vs. OR = 1.04 × 108, respectively). The decrease in RTL in patients reliably correlated with the progression of AMD, and the smallest RTL was observed in late-stage patients. RTL < 0.8 is a significant risk factor for disease progression. The results of our research showed that RTL may be considered as a potential biomarker and a promising predictor of disease progression in patients with early AMD. [ABSTRACT FROM AUTHOR]

Experimental and predicted [sup.207]Pb nuclear magnetic resonance (NMR) parameters of solid-state coordination complexes of lead(II) bromide, lead(II) iodide, and lead(II) chloride with 1,10-phenanthroline are reported. Structural and electronic differences between the 1:1 and 1:2 adducts are reflected by the NMR parameters. The NMR chemical shieldings of the isostructural complexes indicate that the electronic state of the lead(II) center depends on the number of ligands and the halogen anion. The NMR results suggest that the 1:2 adduct may be more stereochemically active than the 1:1 adduct. Key words: 1,10-phenanthroline, lead(II) bromide, lead(II) iodide, [sup.207]Pb NMR, solid-state NMR, density functional theory, zeroth-order regular approximation (ZORA). On rapporte les valeurs experimentales et predites pour les parametres de resonance magnetique nucleaire (RMN) du [sup.207]Pb de complexes de coordination a l'etat solide du bromure de plomb(II), de l'iodure de plomb(II) et du chlorure de plomb(II) avec la 1,10-phenanthroline. Les differences structurales et electroniques entre les adduits 1 : 1 et 1 : 2 sont reflechies par les parametres de RMN. Les blindages chimiques en RMN des complexes isostructuraux indique que l'etat electronique du noyau de plomb(II) depend du nombre de ligands et de l' anion de l' halogene. Les resultats de la RMN suggerent que l'adduit 1 : 2 peut etre stereochimiquement plus actif que l'adduit 1:1. Mots-cles: 1,10-phenathroline, bromure de plomb(II), iodure de plomb(II), [sup.207]Pb RMN, RMN a l'etat solide, theorie de la fonctionnelle de la densite, approximation reguliere d'ordre zero ('ZORA'). [Traduit par la Redaction], Introduction There has been a long interest in the roles of lead, its compounds, and lead-containing materials in the chemistry of electronic devices, optical sensors, and biological systems. Lead(II) oxide, [...]

A series of the theoretical calculations are conducted to present a new somersault mechanism for the oxidation step in enzymatic cytochrome P450 hydroxylation of saturated hydrocarbons with the help of a new class of transient inverted metastable metal hydroperoxides. These hydroperoxides involve the rearrangement of the ground-state metal hydroperoxide to its inverted isomeric form and are supposed to have higher energy levels than the ground state compounds.

A theoretical study that addresses the question of whether nucleophilic addition to the carbonyl groups of acid chlorides, esters, and anhydrides involves an addition elimination pathway or proceeds by a concerted S(sub N)2-like mechanism in the absence of the generally assumed tetrahedral intermediate is presented.

The mechanism of 4a-hydroperoxyflavin oxidation of a series of heteroatom nucleophiles is studied using density functional calculations at the B3LYP/6-31+G(d,p) level. Findings provide an estimate of 40kcal/mol for the O-O bond energy in 4a-flavinhydroperoxide (FIHOOH).

Complex salts of VW5O(sub 19)(super 3-), cis-V2W4O19(super 4-), and W6O(sub 19)(super 2-) anions are investigated using Fourier transform infrared spectroscopy and density functional theory computational methods. Theoretical investigations suggest that the anions alone may not show significant absorption in the region commonly assigned to the M-O(sub t) vibrations.

High-level ab initio and CASSCF calculations on the transition structure for the peroxyformic acid epoxidation of ethylene is carried out. The objective choice of the active space is demonstrated to be critical to the transition structure obtained.

A comparative study is conducted of the evaluated gas-phase activation barricade for the epoxidation of ethylene with dimethyldioxirane (DMDO) and peroxyformic acid (PFA) and E-2-butene indicates identical oxygen atom contributor capacities for both oxidants. The results show that the epoxidation barricades are slightly larger for the damaged alkenes cyclopropene and cyclobutene than for cyclopentene, indicating the reality that the pressure of strain in the transition stage has not reduced substantially.

Research has been conducted on the dimethyl sulfide oxidation. The use of theoretical calculations in investigating this oxidation is described.

Research has been conducted on the dioxirane dimethyldioxirane. The strain energies of these dioxiranes have been investigated via the use of the high-level computational schemes and the dioxirane reactivity towards alkenes has been predicted.

Research has been conducted on the cyclic molecules' strain energy. The effect of substituents on this energy has been examined and the results are presented.

Research is done on the mechanism of 2-trans-2,4-hexadiene triplet interconversion which has been explored using the B3LYP method with 6-31+G(d,p) and cc-pVTZ basis sets. In conclusion, the accessibility of planar triplet intermediates is consistent with triplet excitation transfer steps between the diene isomers that are responsible for the observed quantum chain process in the photoisomerization of the 2,4-hexadienes.

Quantitative theoretical evidence suggests that the neighboring silicon group is silyl peroxides effectively stabilizes the developing negative charge on oxygen in a concerted transfer of an oxygen atom to nucleophiles. The bond dissociation energy of a dialkyl peroxide is 11-12 kcal/mol less than that of the corresponding silyl peroxide.

Research reveals that the diastereoselectivity in the epoxidation of chiral allylic alcohols is dictated by a hydrogen-bonding between the peroxy acids and the allylic alcohols. Computational analysis of the structural implications of the findings are presented.