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1.
Phys Chem Chem Phys ; 25(43): 29940-29950, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37902029

RESUMEN

A new five-dimensional potential energy surface (PES) for H2O-Kr which explicitly includes the intramolecular 2OH overtone state of the H2O monomer is presented. The intermolecular potential energies were evaluated using explicitly correlated coupled cluster theory [CCSD(T)-F12] with a large basis set. Four vibrationally averaged analytical intermolecular PESs for H2O-Kr with H2O molecules in its |00+〉, |02+〉, |02-〉, and |11+〉 states are obtained by fitting to the multi-dimensional Morse/Long-Range potential function form. Each vibrationally averaged PES fitted to 578 points has root-mean-square (RMS) deviations smaller than 0.14 cm-1 and requires only 58 parameters. The combined radial discrete variable representation/angular finite basis representation method and the Lanczos algorithm were employed to calculate the rovibrational energy levels for |00+〉, |02+〉, |02-〉, and |11+〉 states of the H2O-Kr complexes. The calculated |02-〉Πf/e(101) ← |00+〉Σe(000) and |02+〉Πf/e(110) ← |00+〉Σe(101) infrared transitions are in excellent agreement with the experimental values with RMS discrepancies being only 0.007 and 0.016 cm-1, respectively. These analytical PESs can be used to provide reliable theoretical guidance for future infrared overtone spectroscopy of H2O-Kr.

2.
Front Pharmacol ; 13: 842839, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35308239

RESUMEN

In the clinical practice of traditional Chinese medicine, toxic heat and blood stasis syndrome (THBSS) is a common syndrome observed in various critical diseases. Paeoniae Radix Rubra (PRR) has known therapeutic effects on THBSS. However, its pharmacodynamic mechanisms and effective substances in the treatment of THBSS still need further elucidation. Our previous study indicated that THBSS had three stages of progression, and the abnormal biochemical indices of each stage were different. Therefore, this study aimed to elucidate the pharmacodynamic mechanisms and effective substances of PRR for the treatment of THBSS with a stage-oriented strategy. Specifically, research was performed separately in two stable stages of THBSS: the excessive heat and little blood stasis (EHLBS) and blood stasis (BS) stages. THBSS model rats, at different time periods after syndrome initiation (first 5 h for EHLBS and 24 h later for BS), were used to conduct the two-stage investigation. Targeted metabonomics analysis was performed to elucidate the pharmacodynamic mechanisms of PRR in the treatment of EHLBS or BS. Based on the relationship between the individual differences in blood drug concentrations and pharmacodynamic effects, partial least squares regression analysis was employed to screen for the effective substances from the original constituents and metabolites of PRR. We found that PRR could upregulate primary bile acid biosynthesis, glycerophospholipid metabolism, ether lipid metabolism, and five amino acid metabolic pathways (e.g., arginine and proline metabolism) to treat EHLBS. Meanwhile, PRR alleviated BS by upregulating primary bile acid biosynthesis and downregulating glycerophospholipid metabolism. But PRR had no obvious effects on ether lipid metabolism and amino acid metabolism in this stage. In total, 17 and 9 potential effective substances were found in the EHLBS and BS stages, respectively, among which there were only five common compounds between the two stages. To our knowledge, sixteen compounds were regarded as potential effective substances of PRR for the first time. Therefore, the pharmacodynamic mechanisms and effective substances of PRR in the treatment of EHLBS and BS were partly different. Overall, this stage-oriented strategy provides a new way to study the pharmacodynamic mechanisms and effective substances of traditional Chinese drugs.

3.
Molecules ; 24(1)2018 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-30577501

RESUMEN

Carbon bonding is a weak interaction, particularly when a neutral molecule acts as an electron donor. Thus, there is an interesting question of how to enhance carbon bonding. In this paper, we found that the ⁻OCH3 group at the exocyclic carbon of fulvene can form a moderate carbon bond with NH3 with an interaction energy of about -10 kJ/mol. The ⁻OSiH3 group engages in a stronger tetrel bond than does the ⁻OGeH3 group, while a reverse result is found for both ⁻OSiF3 and ⁻OGeF3 groups. The abnormal order in the former is mainly due to the stronger orbital interaction in the ⁻OSiH3 complex, which has a larger deformation energy. The cyano groups adjoined to the fulvene ring not only cause a change in the interaction type, from vdW interactions in the unsubstituted system of ⁻OCF3 to carbon bonding, but also greatly strengthen tetrel bonding. The formation of tetrel bonding has an enhancing effect on the aromaticity of the fulvene ring.


Asunto(s)
Ciclopentanos/química , Carbono/química , Enlace de Hidrógeno , Modelos Moleculares , Electricidad Estática
4.
Zhongguo Zhong Yao Za Zhi ; 32(18): 1906-8, 2007 Sep.
Artículo en Chino | MEDLINE | ID: mdl-18051904

RESUMEN

OBJECTIVE: To observe the effect on P170, LRP, TOPO II of S180 tumour MDR mice for matter by 70% ethanol with Huanglian Jiedu Tang, and then discuss the molecular biology base for clinic. METHOD: 18-22 gramme mice were divided into four groups for normal S180 tumour cell group, matter by 70% ethanol with Huanglian Jiede Tang 100 mg x kg(-1) and 50 mg x kg(-1) in random. Each mouse was given S180 cell 0.2 mL by celiac, and after 24 hours give cisplatin for Injective 3 mg x kg(-1), ip, once a week. And give cyclophosphamide and 5-FU 3 mg x kg(-1), ig, once every day. After 15 days, collect lively mice ascites and give it for onefold normal mice. And then repeat before process. At the same time, every group was given corresponding medicine for 0.2 mL x 10 g(-1). The normal group and the model group were given the same cubage water, all together fore weeks. At last observd the P170, LRP, TOPO II by flow cytometry. RESULT: Matter by 70% ethanol with Huanglian Jiedu Tang could obviously reduce the express of P170 and LRP, and the activiation of TOPO II. CONCLUSION: Matter by 70% ethanol with Huanglian Jiedu Tang can intervene the ocurrence of the multi-drug resistance of tumour cells by regulating the biology gene.


Asunto(s)
Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Sarcoma 180/prevención & control , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Animales , Línea Celular Tumoral , Coptis/química , ADN-Topoisomerasas de Tipo II/metabolismo , Combinación de Medicamentos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Etanol/química , Citometría de Flujo , Ratones , Fitoterapia , Plantas Medicinales/química , Sarcoma 180/metabolismo , Sarcoma 180/patología , Partículas Ribonucleoproteicas en Bóveda/metabolismo
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