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1.
Colloids Surf B Biointerfaces ; 234: 113762, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38244483

RESUMO

Gastric ulcers are worrying, and their worsening conditions may result in bleeding in the internal lining of the stomach. The problem is annoying, and both patients and professionals are still not satisfied with the available treatment options. Hesperidin, a flavonoid molecule with potent anti-inflammatory and antioxidant effects, can work like witchcraft to repair gastric ulcers and preserve the stomach lining. Here, we employed a strategy that involved covering the surface of the nano-lipid carriers (NLCs) with sericin before encasing the hesperidin within (Se-He-NLC). Sericin, a biodegradable polymer increases the muco-adhesion with stomach lining and deployment of hesperidin in controlled manner. Se-He-NLCs were physico-chemically characterized for drug loading, encapsulation, particle size, morphology, drug release, chemical stability, and chemical bonding. The nanocarriers showed first order drug release in a controlled manner. Se-He-NLCs showed better in vitro permeation and ex vivo mucoadhesion, thereby by promoting the in vivo bioavailability. Se-He-NLCs also promoted the reduced glutathione (GSH) and glutathione-S-transferase (GST) levels by 2.24- and 1.61-folds, respectively in the stomach lining, and also the regulation of superoxide dismutase (SOD) and catalase (CAT) activities parallel to the control group. In addition, tissues lipid hydroperoxides (LOOH) and myeloperoxidase (MPO) activity were reduced significantly with Se-He-NLCs administration. Se-He-NLC therapy of stomach ulcers in vivo demonstrated better binding ratio and ulcer healing potential. This approach reveals huge capacity for delivering therapies to treat gastric ulcers based on the clinical significance of sericin coated hesperidin nanocarriers in gastric ulcer treatment.


Assuntos
Hesperidina , Nanopartículas , Sericinas , Úlcera Gástrica , Humanos , Ratos , Animais , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/metabolismo , Hesperidina/farmacologia , Ratos Wistar , Antioxidantes/metabolismo , Superóxido Dismutase/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-37674537

RESUMO

Quercetin was extracted from Portulaca oleracea L. through biphasic acid hydrolysis to investigate its potential as a suppressor of dipeptidyl peptidase IV (DPP-IV) and its hypoglycemic effect in type 2 diabetic mice. The extraction procedure was optimized utilizing the response surface method (RSM) in a single-factor experimental setting. An extraction efficiency of 0.675% was achieved using the following optimized parameters: 0.064 mol/L vitriol, 1 : 109.155 solid-liquid ratio, and 21.408 min ultrasonication. Overall, findings indicate the effectiveness of quercetin extraction. A mouse model for type 2 diabetes was established to receive oral treatment with various quercetin concentrations for 8 weeks. Fasting blood glucose (FBG) and the DPP-IV activity in the serum were significantly reduced. The weight and insulin levels of the mice in the quercetin group were raised compared to those in the model group (P < 0.01). Quercetin dose-dependently inhibited postprandial blood glucose excursions, as demonstrated by the oral glucose tolerance test. These results confirmed that quercetin has hypoglycemic effects and considerably improves insulin sensitivity via DPP-IV targeting.

3.
Chemistry ; 26(43): 9518-9526, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32379364

RESUMO

As redox-active based supercapacitors are known as highly desirable next-generation supercapacitor electrodes, the targeted design of two ferrocene-functionalized (Fc(COOH)2 ) clusters based on coinage metals, [(PPh3 )2 AgO2 CFcCO2 Ag(PPh3 )2 ]2 ⋅7 CH3 OH (SC1 : super capacitor) and [(PPh3 )3 CuO2 CFcCO2 Cu(PPh3 )3 ]⋅3 CH3 OH (SC2 ), is reported. Both structures are fully characterized by various techniques. The structures are utilized as energy storage electrode materials, giving 130 F g-1 and 210 F g-1 specific capacitance at 1.5 A g-1 in Na2 SO4 electrolyte, respectively. The obtained results show that the presence of CuI instead of AgI improves the supercapacitive performance of the cluster. Further, to improve the conductivity, the PSC2 ([(PPh3 )2 CuO2 CFcCO2 ]∞ ), a polymeric structure of SC2 , was synthesized and used as an energy storage electrode. PSC2 displays high conductivity and gives 455 F g-1 capacitance at 3 A g-1 . The PSC2 as a supercapacitor electrode presents a high power density (2416 W kg-1 ), high energy density (161 Wh kg-1 ), and long cycle life over 4000 cycles (93 %). These results could lead to the amplification of high-performance supercapacitors in new areas to develop real applications and stimulate the use of the targeted design of coordination polymers without hybridization or compositions with additive materials.

4.
Ultrason Sonochem ; 39: 420-429, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28732964

RESUMO

Two novel Ru(II) complexes [(η6-p-cymene)RuCl(L1)]PF6 (R1) and [(η6-C6H6)RuCl(L1)]PF6 (R3) with ligand (E)-4-(methylthio)-N-((quinolin-2-yl)methylene)benzenamine (L1), were synthesized and investigated using elemental analysis, IR, 1H NMR, 13C NMR spectroscopy and X-ray crystallography. Complexes R1 and R3 have coordination environments with formulated (η6-p-cymene)Ru(N2Cl) and (η6-C6H6)Ru(N2Cl) respectively. The thermal stabilities of compounds R1 and R3 were studied by thermal gravimetric (TG) and differential scanning calorimetry (DSC). The binding of the complexes R1 and R3 to calf thymus DNA (CT DNA) was investigated by using electronic absorption spectra, fluorescence and redox behavior studies. Such experimental data showed that there are interactions between complexes and CT-DNA and the nature of this binding is electrostatic interaction type. Calcination of ultrasonic treated R1 and R3 results in the formation of nanoparticles of RuO2. The nanoparticles were characterized by IR spectroscopy and X-ray diffraction (XRD). Also size and morphology of nanoparticles were investigated by scanning electron microscopy (SEM).


Assuntos
Nanoestruturas/química , Compostos Organometálicos/química , Polímeros/química , Compostos de Rutênio/química , Rutênio/química , Ondas Ultrassônicas , Animais , Bovinos , DNA/química , Temperatura Alta , Ligantes , Modelos Moleculares , Conformação Molecular , Oxirredução
5.
Mitochondrial DNA B Resour ; 2(2): 486-488, 2017 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33473872

RESUMO

The complete mitogenome sequence of the masked shrew (Sorex caecutiens) was determined using long PCR. The genome was 17,096 bp in length and contained 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, one origin of L strand replication, and one control region. The overall base composition of the heavy strand is A (32.9%), C (24.5%), T (29.3%), and G (13.3%). The base compositions present clearly the A-T skew, which is most obviously in the control region and protein-coding genes. The extended termination-associated sequence domain, the central conserved domain and the conserved sequence block domain are defined in the mitochondrial genome control region of the masked shrew. Mitochondrial genome analyses based on MP, ML, NJ, and Bayesian analyses yielded identical phylogenetic trees. The five Sorex species formed a monophyletic group with the high bootstrap value (100%) in all examinations.

6.
Acta Crystallogr C Struct Chem ; 72(Pt 10): 720-723, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27703117

RESUMO

A fixed hydrogen-bonding motif with a high probability of occurring when appropriate functional groups are involved is described as a `supramolecular hydrogen-bonding synthon'. The identification of these synthons may enable the prediction of accurate crystal structures. The rare chiral hydrogen-bonding motif R53(10) was observed previously in a cocrystal of 2,4,6-trichlorophenol, 2,4-dichlorophenol and dicyclohexylamine. In the title solvated salt, 2C4H12N+·C6H3Cl2O-·(C6H3Cl2O-·C6H4Cl2O)·2C4H8O, five components, namely two tert-butylammonium cations, one 2,4-dichlorophenol molecule, one 2,4-dichlorophenolate anion and one 2,6-dichlorophenolate anion, are bound by N-H...O and O-H...O hydrogen bonds to form a hydrogen-bonded ring, with the graph-set motif R53(10), which is further associated with two pendant tetrahydrofuran molecules by N-H...O hydrogen bonds. The hydrogen-bonded ring has internal symmetry, with a twofold axis running through the centre of the 2,6-dichlorophenolate anion, and is isostructural with a previous and related structure formed from 2,4-dichlorophenol, dicyclohexylamine and 2,4,6-trichlorophenol. In the title crystal, helical columns are built by the alignment and twisting of the chiral hydrogen-bonded rings, along and across the c axis, and successive pairs of rings are associated with each other through C-H...π interactions. Neighbouring helical columns are inversely related and, therefore, no chirality is sustained, in contrast to the previous case.

7.
Phytochemistry ; 122: 294-300, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26790964

RESUMO

Phytochemical investigation of the aerial parts of Chimonanthus salicifolius resulted in the isolation of two sesquiterpenoids, 8α-hydroxy-T-muurolol and (1α,6ß,7ß)-cadinane-4-en-8α,10α-diol, together with 13 known compounds. The 15 structures were established by means of 1D and 2D NMR spectroscopy. The relative and absolute configurations of 8α-hydroxy-T-muurolol and 8α,11-elemodiol were achieved by NOESY experiments and X-ray crystallography using CuKα radiation. 8α-hydroxy-T-muurolol and (1α,6ß,7ß)-cadinane-4-en-8α,10α-diol showed immunosuppressive activities in a dose-dependent manner.


Assuntos
Calycanthaceae/química , Sesquiterpenos/química , Terpenos/química , Cristalografia por Raios X , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos Policíclicos , Estereoisomerismo
8.
PLoS One ; 10(3): e0120211, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25789618

RESUMO

Two novel coordination compounds of half-sandwiched ruthenium(II) containing 2-(5-fluorouracil)-yl-N-(pyridyl)-acetamide were synthesized, and their intercalation binding modes with calf thymus DNA were revealed by hyperchromism of ultraviolet-visible spectroscopy; the binding constants were determined according to a Langmuir adsorption equation that was deduced on the base of careful cyclic voltammetry measurements. The two compounds exhibited DNA intercalation binding activities with the binding constants of 1.13×106 M-1 and 5.35 ×105 M-1, respectively.


Assuntos
Complexos de Coordenação/síntese química , DNA/química , Fluoruracila/química , Substâncias Intercalantes/síntese química , Rutênio/química , Algoritmos , Animais , Bovinos , Complexos de Coordenação/metabolismo , DNA/metabolismo , Técnicas Eletroquímicas , Eletrodos , Substâncias Intercalantes/metabolismo , Espectrofotometria Ultravioleta
9.
Ying Yong Sheng Tai Xue Bao ; 25(2): 620-4, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24830265

RESUMO

Genetic diversity is the base of the species diversity and ecosystem diversity, and also the foundation for biological evolution and species differentiation. Furthermore, genetic diversity is important evidence for evaluation of biological resources of nature. The genetic diversity data from a wide variety of rodents have many complex applications. We summarized the application of rodent prevention, the origin and differentiation including evolutionary history of rodents, the potential adaptation of rodents, the dynamics of population and regulatory mechanisms, and the conservation biology of rodents. Researches in the future should focus on the systematic study on the relationships between population dynamics and genetic diversity, and long-term monitoring of genetic diversity of rodents.


Assuntos
Variação Genética , Roedores/genética , Animais , Evolução Biológica , Dinâmica Populacional
10.
Acta Crystallogr C Struct Chem ; 70(Pt 2): 207-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24508971

RESUMO

The title complex, 2C12H24N(+)·C6H3Cl2O(-)·C6H2Cl3O(-)·C6H4Cl2O, consists of three different achiral components, dicyclohexylammonium cations, 2,4,6-trichlorophenolate anions and H-atom-bridged 2,4-dichlorophenolate/2,4-dichlorophenol units, held together by O-H···N and O-H···O hydrogen bonds to form a chiral hydrogen-bonded ring. A helical cylinder is established by the packing of these rings along a crystallographic 41 screw axes. Helical cylinders may be generated from each other by translation, resulting in the formation of the chiral crystal. Neighbouring parallel helical cylinders are associated by van der Waals interactions only.


Assuntos
Ânions/química , Cátions/química , Clorofenóis/química , Cicloexilaminas/química , Cristalografia por Raios X , Ligação de Hidrogênio , Estrutura Molecular , Estereoisomerismo
11.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): m146, 2007 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-21200500

RESUMO

The asymmetric unit of the title compound, (C(5)H(14)N(2))[SbCl(5)]·H(2)O, consists of an N-methyl-piperazinediium cation, a penta-chloridoanti-monate anion with the Sb(III) ion in a slightly distorted square-pyramidal coordination environment, and one solvent water mol-ecule. The crystal structure is stabilized by inter-molecular N-H⋯Cl, O-H⋯Cl and N-H⋯O hydrogen bonds.

12.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): m167, 2007 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-21200515

RESUMO

The title compound, (C(11)H(14)N(4)O(4))[SbCl(4)]·H(2)O, comprises a protonated doxofyllinium cation [7-(1,3-dioxolan-2-ylmeth-yl)-1,3-dimethyl-2,6-dioxo-3,7-dihydro-1H-purin-9-ium], an [SbCl(4)](-) anion and a water mol-ecule linked by N-H⋯O and O-H⋯Cl hydrogen bonds: the [SbCl(4)](-) anions form centrosymmetric dimers via weak Sb⋯Cl inter-actions [Sb⋯Cl = 3.1159 (9) Å]. The geometrical arrangement in the crystal structure is characterized by slipped π-π stacking of the parallel purine ring systems, with an inter-planar separation of 3.32 Å.

13.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): o193, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21200758

RESUMO

In the title salt, C(19)H(23)N(2)O(+)·Cl(-)·H(2)O, the ions and the water mol-ecule are held together by O-H⋯Cl, N-H⋯Cl, O-H⋯O, O-H⋯N and C-H⋯Cl hydrogen bonds, forming a three-dimensional framework. The vinyl group is disordered over two orientations with refined occupancies of 0.564 (16) and 0.436 (16). The cell parameters of the title compound have been reported previously [Griffiths (1952 ▶). Acta Cryst.5, 290-291].

14.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): o30, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21200864

RESUMO

The title compond, C(19)H(24)O(5)·H(2)O, has two gibberellin A4 mol-ecules and two water mol-ecules in the asymmetric unit. The A and B rings have chair conformations, whereas the C and D rings have envelope conformations; the two rings which contain the lactone and carbonyl bridge adopt chair and envelope conformations. The crystal structure is established by O-H⋯O hydrogen bonds and supported by C-H⋯O hydrogen bonds.

15.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): o346, 2007 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-21200908

RESUMO

In the asymmetric unit of the title compound, C(2)H(10)N(2) (2+)·2C(7)H(7)O(3)S(-)·H(2)O, there are two independent 4-methyl-benzene-sulfonate anions, one ethyl-enediammonium cation and a water mol-ecule. The present redetermination was carried out to improve the treatment of disorder, which was not refined in the previous study [Ahn & Kim (1985 ▶). J. Korean Chem. Soc.29, 335-340]. One of the sulfonate groups is disordered over two positions, with site-occupancy factors of 0.588 (14) and 0.412 (14). Inter-molecular N-H⋯O and O-H⋯O hydrogen bonds hold the three components together, affording a layer structure extending parallel to the (001) plane.

16.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): o347, 2007 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-21200909

RESUMO

In the title compound, C(11)H(14)N(4)O(4)·C(2)HCl(3)O(2), the dioxolane ring adopts an envelope conformation. Doxophylline [7-(1,3-dioxolan-2-yl-meth-yl)-1,3-dimethyl-3,7-dihydro-1H-purine-2,6-dione] and trichloro-acetic acid mol-ecules are linked by O-H⋯N and C-H⋯O hydrogen bonds.

17.
J Phys Chem A ; 110(29): 9261-6, 2006 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-16854042

RESUMO

Density functional theory calculations at the B3LYP/6-31+G(d,p) level of theory have been performed to explore proton exchanges between phenols and ammonia or amines, which can be used to account for previous NMR experiments. For the parent phenol-NH(3) system, a transition state with a symmetric phenolate-NH(4)(+)-like structure, which lies about 35 kcal mol(-1) in energy above the hydrogen-bonded complex, has been successfully located. An intrinsic reaction coordinate (IRC) analysis indicates that the proton exchange is a concerted process, which can be roughly divided into four continuous subprocesses. A series of para-substituted phenol-NH(3) systems have been considered to investigate the substituent effect. Whereas introduction of an electron-withdrawing group on the phenol appreciably reduces the barrier, an opposite effect is observed for an electron-donating group. Moreover, it has been disclosed that there exists a good linear correlation between the activation barriers and the interaction energies between the phenols and NH(3), indicating the important role of proton transfer (or hydrogen bonding) in determining the proton exchange. Also considered are the proton exchanges between phenol and amines and those for some sterically hindered systems. The results show that the phenol tends to exchange hydrogen with the amines, preferably the secondary amines, and that the steric effect is favorable for the proton exchange, which imply that, as the IRC analysis suggested, besides the proton transfer, the flip of the ammonium-like moiety may play a significant role in the course of proton exchange. For all of these systems, we investigated the solvent effects and found that the barrier heights of proton exchange decrease remarkably as compared to those in a vacuum due to the ion pair feature of the transition state. Finally, we explored the phenol radical cation-NH(3) system; the barrierless proton transfer and remarkably low barrier (5.2 kcal mol(-1)) of proton exchange provide further evidence for the importance of proton transfer in the proton exchange.


Assuntos
Aminas/química , Amônia/química , Fenóis/química , Prótons , Cátions/química , Simulação por Computador , Radicais Livres/química , Ligação de Hidrogênio , Estrutura Molecular , Oxigênio/química
18.
Acta Crystallogr C ; 61(Pt 10): o593-5, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16210766

RESUMO

The title complex, C8H6O4.2C6H7N, consists of two crystallographically independent 1:2 clusters of benzene-1,3-dicarboxylic acid and 4-methylpyridine. Each cluster, the components of which are linked by O-H...N hydrogen bonds, is almost planar by alignment of C-H...O hydrogen bonds. Herring-bone ribbons of clusters are formed by other C-H...O hydrogen bonds, and these ribbons are further packed to form a laminar structure by pi-pi interactions.


Assuntos
Ácidos Ftálicos/química , Picolinas/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular
19.
Acta Crystallogr C ; 61(Pt 6): m311-2, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15930675

RESUMO

In the title compound, [FeII(NCS)2(CH6N4S)2], the Fe(II) cation is surrounded by two S atoms and two N atoms from thiocarbohydrazide groups and by two N atoms from thiocyanate groups. The geometry around the FeII cation, which is located on a center of inversion, is distorted octahedral. The thiocarbohydrazide molecule assumes a cis-trans conformation, which is reinforced by an N-H...N hydrogen bond. Molecules of the title compound are connected via intermolecular N-H...S and N-H...N hydrogen bonds to form a three-dimensional network structure.

20.
Acta Crystallogr C ; 61(Pt 4): m197-9, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15805621

RESUMO

The title compound, (C6H9N2)[ZnCl3(C6H8N2)], consists of one 2-amino-5-methylpyridinium cation and one (2-amino-5-methylpyridine)trichlorozincate(II) anion, which are held together by N-H...Cl hydrogen bonds and pi-pi interactions. The cation and the pyridine ligand show similar geometric features, except for the N-C bond lengths. Molecules of the title compound are connected by N-H...Cl hydrogen bonds to form chiral chains; these chains are associated further by C-H...Cl hydrogen bonds to form layers, which are in turn linked by pi-pi interactions.


Assuntos
Compostos Organometálicos/química , Compostos de Piridínio/química , Zinco/química , Cristalografia por Raios X , Ligação de Hidrogênio , Conformação Molecular , Compostos Organometálicos/síntese química , Compostos de Piridínio/síntese química , Espectrofotometria Infravermelho
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