The search of new materials having suitable characteristics to trap hydrogen for fuel applications is greatly challenging due to the stringent requirements that such materials must meet. In this ...sense, with the aid of computational chemistry, significant advances can be achieved. The present work explores the adsorption of hydrogen molecules by lithium clusters (Lin, where n = 1–6) coordinated to a graphitic carbon nitride (heptazine, gC3N4) cavity. The study was conducted using the density functional theory (M06-2X-D3) in combination with the def2-TZVP basis set. Our results suggest that lithium atoms in the gC3N4-cavity can coordinate up to 10 hydrogen molecules with bond energies in the range −0.10 to −0.19 eV. The gC3N4Li5+ and gC3N4Li6 systems resulted to be the most promising in terms of lithium coordination. They feature the highest stabilization energies for hydrogen adsorption. According to the calculated Gibbs free energies for these systems, H2 adsorption remains a spontaneous process even at 400 K.
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•The gC3N4Li5+ and gC3N4Li6 are capable to accepted 8H2 and 10H2 respectlive.•Energies of adsorption of hydrogen fell in the range from −2.21 to −4.39 kcal/mol.•NBO showed that hydrogen are bonded via van der Waals interactions as physisorption.
We report the design, synthesis, and characterization of two new fluorescent molecular rotors of boron derived from Schiff bases: ...(2,4,8,10-tetra-tert-butyl-6-phenyldibenzod,h1,3,6,2dioxazaboronine (3) and 1,4-bis(2,4,8,10-tetra-tert-butyldibenzod,h1,3,6,2dioxazaboronin-6-yl)benzene (4), as well as the free ligand 2-(3,5-di-tert-butyl-2-hydroxyphenyl)iminomethyl-4,6-di-tert-butylphenol 1. All compounds were fully characterized by NMR (1H, 11B, and 13C), IR, UV/vis, fluorescence spectroscopy, and high-resolution mass spectrometry. The crystal structures of 3 and 4 showed tetracoordinated boron atoms with semiplanar skeleton ligands. The free rotation of the fluorescent molecular rotor, only observed in the binuclear compound, was decreased with increasing viscosity, while the quantum yield was increased. Interestingly, the property of reversible thermochromism was found in organoboron 4 in the solid state. DFT calculations to determine the both complexes have free rotation around the CPh–B1 bond. The boron compounds 3 and 4 have shown low cytotoxicity activity in cell line A-431 and low green staining in cells.
Klinefelter syndrome (KS) is the most common sex chromosome aneuploidy. A distinctive characteristic of KS is oligozoospermia. Despite multiple studies that have described the natural history of the ...degenerative process of germ cells in patients with KS, the molecular mechanisms that initiate this process are not well characterized. MicroRNA (miRNA)-mediated post-transcriptional control mechanisms have been increasingly recognized as important regulators of spermatogenesis; however, only a few studies have evaluated the role of miRNAs in the gonadal failure of these patients. Here, we describe a differential expression profile for the miRNAs in testicular tissue samples taken from KS patients. We analysed testicular tissue samples from 4 KS patients and 5 control patients (obstructive azoospermia) through next-generation sequencing, which can provide information about the mechanisms involved in the degeneration of germ cells. A distinctive differential expression profile was identified for 166 miRNAs in the KS patients: 66 were upregulated, and 100 were downregulated. An interactome analysis was performed for 7 of the upregulated and the 20 downregulated miRNAs. The results showed that the target genes are involved in the development, proliferation, and differentiation processes of spermatogenesis, which may explain their role in the development of infertility. This is the first report of a miRNA expression profile generated from testicular tissue samples of KS patients.
The fluorescent silk fibroin (FSF) is useful in a number of biomedical applications. However, some FSFs are less useful for medical applications because they are derived from toxic compounds. Here we ...report for the first time a fast (∼20 min), ultrasonic assisted, eco-friendly synthesis of four fluorescent organotin Schiff compounds using the corresponding aldehyde, benzoic hydrazide, and diorganotin oxide ( 1 : MeO-L-SnPh 2 , 2 : t Bu 2 -L-SnPh 2 , 3 : HO-L-SnPh 2 , and 4 : HO-L-SnBu 2 ). These compounds were fully characterized by NMR spectroscopy ( 1 H, 13 C, and 119 Sn), HRMS, and UV/Vis and fluorescence spectroscopy. Single crystal X-ray diffraction investigations of complexes 1 and 2 are also reported. The as-prepared organotin Schiff compounds exhibit fluorescence at ambient temperature with good photophysical properties (fluorescence quantum yields Φ : 18–55%). These organotin compounds serve as fluorescent dyes in silk fibroin ( Bombyx mori ). The organotin dyed fluorescent silk fibroin showed a uniform staining, high viability, and good capacity to retain organotin compounds which might be used as innocuous scaffolds in tissue engineering.
This research describes the theoretical study of the adsorption of lithium clusters on graphene and the ability to capture hydrogen molecules. The results of the studied structures showed that the ...Li1C54H18+ system is capable of accepting three hydrogen molecules showing adsorption energies of 0.12 eV. On the other hand, it is important to note that in LinC54H18 n = 2–6 systems, the lithium atoms that do not interact with the graphene surface, they can adsorb up to four hydrogen molecules. The Li6C54H184H2 system presented a higher adsorption energy value of 0.31 eV. Finally, the Li–H2 interactions were characterized by a NBO analysis, which showed that hydrogen atoms are the donors and lithium atoms are the acceptors.
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•The computational studies reveal physisorption of H2 molecule on Li1C54H18+ system.•The studied structures showed that the Li1C54H18+ system is capable of accepting 3H2.•The lithium clusters into the graphene surface, facilitates that H2 can adsorb easily.
Background
Morin is a flavonoid found in many edible fruits. The hippocampus and entorhinal cortex play crucial roles in memory formation and consolidation. This study aimed to characterize the ...effect of morin on recognition and space memory in healthy C57BL/6 adult mice and explore the underlying molecular mechanism.
Methods
Morin was administered i.p. at 1, 2.5, and 5 mg/kg/24 h for 10 days. The Morris water maze (MWM), novel object recognition, novel context recognition, and tasks were conducted 1 day after the last administration. The mice's brains underwent histological characterization, and their protein expression was examined using immunohistochemistry and Western blot techniques.
Results
In the MWM and novel object recognition tests, mice treated with 1 mg/kg of morin exhibited a significant recognition index increase compared to the control group. Besides, they demonstrated faster memory acquisition during MWM training. Additionally, the expression of pro‐brain‐derived neurotrophic factor (BDNF), BDNF, and postsynaptic density protein 95 proteins in the hippocampus of treated mice showed a significant increase. In the entorhinal cortex, only the pro‐BDNF increased. Morin‐treated mice exhibited a significant increase in the hippocampus's number and length of dendrites.
Conclusion
This study shows that morin improves recognition memory and spatial memory in healthy adult mice.
Morin improves recognition and spatial memory in healthy adult mice. We suggest that the molecular mechanism for these effects involves the increased production and BDNF secretion by astrocytes.
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•The M/g-C3N4+ complexes have been seen as interesting adsorbents of metformin.•M/g-C3N4, M: Li, Na, K have values of 39.29–19.13 kcal/mol favorable for drug delivery.•NBO shows donor ...orbitals belong to the nitrogen atoms of metformin.
Metformin is one of the important anti-diabetic drugs. DFT calculations have been performed to study properties of adsorption of metformin onto M/g-C3N4+,+2,+3, where M: Li, Na, K, Be, Mg, Ca, B, Al, and Ga. Optimized structures of all systems were calculated using the ONIOM computational method. The results were used to calculate the absorption energy (Eads) with the PBE0-D3(BJ)/def2-TZVP method. The adsorption energy values for the most stable configurations are 19.1–131.6 kcal/mol. By adsorption of metformin on M/g-C3N4+,+2,+3 surfaces, the ionization potential values of M/g-C3N4+, M: Li, Na and K are low, which means that the stability of M: Li, Na and K systems are higher than the other systems (groups 2 and 3). The M/g-C3N4+ complexes have been seen as interesting adsorbents of metformin molecule.
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•The computational studies reveal physisorption of adrucil on La-CTF-03+ system.•The lanthanum atom on CTF-0 facilitates the adsorption of adrucil molecule.•The NBO analysis shows the ...adrucil acts as a strong donor towards the CTF-0.
Fluorouracil is a chemotherapy medication used in the treatment of many cancers. Motivated in the development of new drug delivery, in the present work, the adsorption of adrucil drug on La-CTF-0+3 was studied. Electron and interaction properties of La-CTF-0+3 with the adrucil molecule have been explored by DFT. The optimized structure and energy were investigated usin the PBE0/def2-TZVP method. Results suggest that adrucil molecule can be adsorbed physically on the La-CTF-0+3, with adsorption energy of 69.82 kcal/mol. The HOMO-LUMO orbitals of the system indicate that the electron properties of the La-CTF-03+ are slightly altered after the adsorption of the drug on La-CTF-0+3. The natural bond orbital calculation shows charge transfer between the electron donor oxygen on adrucil and the lanthanum atom, acceptor. This research provides new insights into the development of drug delivery systems.
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