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Context: The aggregation and adsorption of amantadine and sodium dodecyl sulfate on the boron nitride nanotubes in aqueous system were investigated, employing the classical molecular dynamics method. The aqueous system containing amantadine and sodium dodecyl sulfate was investigated by self-diffusion of the molecules, with particular emphasis on their center of mass mean square displacement. The radial distribution function and dipole moment measurement were used to analyze the water effect on the aggregation and molecular interaction between amantadine and sodium dodecyl sulfate in the complex. In turn, the amantadine molecules are able to develop water monolayers at the aqueous solution but show no noticeable aggregated adsorption in the fluid. In contrast, sodium dodecyl sulfate self-aggregation on the boron nitride nanotube efficiently occurs, and so the effect of sodium dodecyl sulfate on aggregated adsorption of amantadine was studied. Our results show that in the presence of sodium dodecyl sulfate at critical micelle concentration, its effect on the aggregation of amantadine was enhanced onto boron nitride nanotube compared to just pure sodium dodecyl sulfate or amantadine on boron nitride nanotube. Our simulations show a remarkable restructuring and enhanced orientation of the water molecules around sodium dodecyl sulfate and amantadine adsorbed on boron nitride nanotube., Method: All molecular dynamics simulations were done using NAMD-2.9 package with CHARMM-36 force field. The nanotube PDB file was made by VMD with (12, 12) indexes. The nanotube atoms were considered to be fixed and periodic during the simulation process, and the ends did not cap with hydrogens. The initial PDB file of components was saved from ChemOffice software, and the webservers to obtain the charge and topology files were Reddb and Swiss Param webservers. The VMD software was used for structural visualizations and graphical analysis., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The possibility of plutonium (Pu) intake by radiation workers can not be ruled out. Transportation of Pu(IV) to various organs/cells is mainly carried through iron-carrying protein, serum transferrin (sTf), by receptor-mediated endocytosis. Understanding the Pu-sTf interaction is a primary step toward future design of its decorporating agents. We report MD simulations of Pu(IV) binding with sTf and look out for its decorporation at extracellular pH using suitable ligands. MD simulations were carried out in polarizable water environment at different protonation states of the protein. Results unravel the binding motif of Pu(IV): (1) sTf binds the ion in closed conformation at extracellular serum pH with carbonate as synergistic anions, (2) change in protonation state of dilysine (K206 and K296)-trigger and that of the carbonate ion at acidic endosomal pH is found to cause conformational changes of protein, conducive for the heavy ion to be released, although; (3) strong electrostatic interaction between D63 in the binding-cleft and Pu(IV) is found not to ever set free the ion. In an endeavour to decorporate Pu(IV), fragmented molecular form of hydroxypyridinone (HOPO) and catechol (CAM)-based ligands are docked at the binding site (BS) of the protein and metadynamics simulations are conducted. Pu(IV) binding at BS is found to be so strong that it was not detached from BS with the docked HOPO. However, for the identical set of simulation parameters, CAM is found to facilitate dislodging the heavy ion from the protein's binding influence. Differential behaviour of the two chelators is further explored. Fragmented molecular form of hydroxy-pyridinone (HOPO) and catecholamide (CAM) ligands were docked at the binding-site (BS) of human serum transferrin (sTf) to explore their feasibility as plausible Pu(IV) decorporating agents by employing metadynamics method. CAM was found to dislodge Pu from the sTf BS, while HOPO could not.

Socio-demographic characteristics of mothers have been associated with exclusive breastfeeding duration, but little is known about the association with maternal full- and part-time employment and return to work in European countries. To study the associations between breastfeeding, any and almost exclusive (infants receiving breast milk as their only milk) breastfeeding, at 4 months of infant's age and the socio-demographic and occupational characteristics of mothers. We used the EDEN mother-child cohort, a prospective study of 2002 singleton pregnant women in two French university hospitals. We selected all mothers (n = 1,339) who were breastfeeding at discharge from the maternity unit. Data on feeding practices were collected at the maternity unit and by postal questionnaires at 4, 8 and 12 months after the birth. Among infants breastfed at discharge, 93 % were still receiving any breastfeeding (83 % almost exclusive breastfeeding) at the 3rd completed week of life, 78 % (63 %) at the 1st completed month, and 42 % (20 %) at the 4th completed month. Time of return to work was a major predictor for stopping breastfeeding: the sooner the mothers returned to work, the less they breastfed their babies at 4 months of infant's age, independently of full-time or part-time employment. The association was stronger for almost exclusive breastfeeding mothers than for any breastfeeding ones. In a society where breastfeeding is not the norm, women may have difficulties combining work and breastfeeding. Specific actions need to be developed and assessed among mothers who return to work and among employers. Keywords Breastfeeding duration * Employment * Socioeconomic status * France, Background Breastfeeding has been shown to have short- and long-term beneficial effects on infant health and it is widely recognised as the optimal infant feeding method. The World Health Organization [...]

To study the relationship between pre-pregnancy body mass index (BMI) and weight gain during pregnancy with pregnancy and birth outcomes, with a focus on gestational diabetes and hypertension and their role in the association with fetal growth. We studied 1,884 mothers and offspring from the Eden mother-child cohort. Weight before pregnancy (W1) and weight after delivery (W2) were collected and we calculated BMI and net gestational weight gain (netGWG = (W2 - W1)/(weeks of gestation)). Gestational diabetes, hypertension gestational age and birth weight were collected. We used multivariate linear or logistic models to study the association between BMI, netGWG and pregnancy and birth outcomes, adjusting for center, maternal age and height, parity and average number of cigarettes smoked per day during pregnancy. High BMI was more strongly related to the risk of giving birth to a large-for-gestational-age (LGA) baby than high netGWG (odds ratio OR [95% CI] of 3.23 [1.86-5.60] and 1.61 [0.91-2.85], respectively). However, after excluding mothers with gestational diabetes or hypertension the ORs for LGA, respectively weakened (OR 2.57 [1.29-5.13]) for obese women and strengthened for high netGWG (OR 2.08 [1.14-3.80]). Low in comparison to normal netGWG had an OR of 2.18 [1.20-3.99] for pre-term birth, which became stronger after accounting for blood pressure and glucose disorders (OR 2.70 [1.37-5.34]). Higher net gestational weight gain was significantly associated with an increased risk of LGA only after accounting for blood pressure and glucose disorders. High gestational weight gain should not be neglected in regard to risk of LGA in women without apparent risk factors. Keywords Obesity * Pregnancy * Gestational diabetes * Hypertension * Birth weight, Introduction The prevalence of obesity has been increasing worldwide, especially among young women susceptible to become pregnant. In France, although the prevalence is lower than in the United States, the [...]