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1.
Phys Chem Chem Phys ; 26(4): 3092-3100, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38180442

RESUMO

Kagome lattices may have numerous exotic physical properties, such as stable ferromagnetism and topological states. Herein, combining the particle swarm structure search method with first-principles calculations, we identify a two-dimensional (2D) kagome Mo2Se3 crystal structure with space group P6/mmm. The results show that 2D kagome Mo2Se3 is a 100% spin-polarized topological nodal line semimetal and exhibits excellent ambient stability. The band crossing points form two nodal loops around the high-symmetry points Γ and K. On the other hand, Mo2Se3 shows intrinsic ferromagnetism with a large magnetic moment of 3.05 µB per Mo atom and magnetic anisotropy energy (MAE) of 4.78 meV. Monte Carlo simulations estimate that Mo2Se3 possesses a high Curie temperature of about 673 K. In addition, its ferromagnetic ground state can be well preserved under external strain, and the MAE can be improved by increasing the strain. More importantly, the position of each nodal line can be adjusted to the Fermi level through hole doping. This multifunctional 2D magnetic material that combines spin and topology has great potential in the field of nanoscale spintronic devices.

2.
AAPS PharmSciTech ; 23(7): 261, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36131215

RESUMO

Oral delivery is considered the preferred route of administration due to its convenience and favorable compliance. However, this delivery often faces difficulties, such as poor solubility, limited absorption, and undesirable stability, especially for some volatile oils. The aim of this study was to develop self-emulsifying drug delivery systems (SEDDS) containing cinnamaldehyde (CA) to overcome these shortcomings. The CA-SEDDS were spherical and smooth with an average size of 14.96 ± 0.18 nm. Differential scanning calorimetry (DSC) and attenuated total reflection by Fourier transform infrared (ATR-FTIR) showed that CA has been successfully loaded into SEDDS. The accumulative release of CA-SEDDS (73.39%) was approximately 2.14-fold that of free CA when using simulated intestinal fluid as the release medium. A scanning electron microscope was used to observe the mucus network structure. Rheological tests found that CA-SEDDS can appropriately enhance the viscosity of the mucus system. We found from tissue distribution studies that CA was more widely distributed in various tissues in the CA-SEDDS group compared to the free CA group. The cinnamaldehyde and cinnamon acid also accumulated more in various tissues in the CA-SEDDS group than in the free CA group, especially in the kidney. These findings hinted that SEDDS exhibited lower irritation, good release, and penetration, which demonstrated great potential for utilizing CA. Our research supports the rational implications of SEDDS in delivering similar volatile substances by improving the solubility, mucus penetration, and stability, resulting in excellent clinical efficacy.


Assuntos
Sistemas de Liberação de Medicamentos , Óleos Voláteis , Acroleína/análogos & derivados , Sistemas de Liberação de Medicamentos/métodos , Emulsificantes/química , Emulsões/química , Muco , Solubilidade , Distribuição Tecidual
3.
Drug Dev Ind Pharm ; 47(8): 1223-1234, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34779328

RESUMO

PURPOSE: To develop a liquid crystal (LC) precursor that can be used as a novel vaginal delivery system for Itraconazole (ITZ) and evaluate its pharmacodynamics. METHODS: The LC precursor was prepared by using phytantriol (PYT) as lipid matrix and N, N-dimethylformamide (DMAC) as solvent. Swelling studies were performed to assess the phase conversion ability. The formulations were characterized by crossed polarized light microscopy (CPLM), small-angle X-ray scattering (SAXS). Moreover, the rheological and in vitro drug release behavior were investigated. Then the vaginal retention time of ITZ in the optimal prescription was evaluated. Finally, the pharmacodynamics studies of the ITZ-loaded LC precursor were performed in a mouse model of vulvovaginal candidiasis (VVC). RESULTS: The LC precursor could transform to LC gels after administration into the vagina. Based on PLM and SAXS, the LC gels, formed after phase-conversion, were cubic LC. The LC precursor was non-Newtonian, while the LC gels exhibited a pseudo-plastic fluid behavior. In vitro release results revealed that F2 (68.0%) had a higher cumulative drug release than that of F1 (59.17%) at 72 h. Most of the LC gels could be retained in the vagina of mice for 24-36 h. Pharmacodynamics studies showed that there was only mild inflammation or no inflammatory stimulation in the control group. The ITZ-loaded LC precursor significantly improved the symptoms of vaginitis in mice and had a better therapeutic effect than that of the positive control group. CONCLUSIONS: The ITZ-loaded LC precursor would be a promising formulation for vaginal drug delivery.


Assuntos
Itraconazol , Cristais Líquidos , Animais , Antifúngicos/química , Parto Obstétrico , Feminino , Géis , Itraconazol/química , Itraconazol/farmacologia , Cristais Líquidos/química , Camundongos , Gravidez , Espalhamento a Baixo Ângulo , Difração de Raios X
4.
Clin Exp Hypertens ; 42(5): 420-427, 2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31760826

RESUMO

Background: Honey has been shown to have multiple positive effects on human health. However, data on the associations of honey consumption with prehypertension are scarce. The aim of this study was to investigate whether honey consumption is associated with prehypertension in a Chinese population. Method: A cross-sectional study was conducted in 4,561 individuals aged ≥40 years. A validated 100-item semi-quantitative food frequency questionnaire was used to assess honey consumption. Blood pressure was measured at least twice by trained nurses. Multiple logistic regression models were used to explore the associations between honey consumption and prehypertension. Results: After adjustment for potential confounders, the odds ratios and 95% confidence intervals of prehypertension across increasing frequency of honey consumption were 1.00 (reference) for almost never, 1.17 (0.96, 1.41) for ≤6 times/week, and 1.25 (0.86, 1.84) for ≥7 times/week in men (P for trend = 0.09); 1.00 (reference) for almost never, 0.76 (0.62, 0.92) for ≤6 times/week, and 0.84 (0.63, 1.12) for ≥7 times/week in women (P for trend = 0.055), respectively. Conclusion: Our results showed that light-to-moderate intake of honey was associated with lower prevalence of prehypertension in women, but not men. Future studies are required to confirm these associations.


Assuntos
Mel , Pré-Hipertensão , Pressão Sanguínea/fisiologia , China/epidemiologia , Estudos Transversais , Comportamento Alimentar/fisiologia , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Pré-Hipertensão/diagnóstico , Pré-Hipertensão/epidemiologia , Prevalência , Fatores de Risco , Fatores Sexuais
5.
AAPS PharmSciTech ; 21(6): 224, 2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32749554

RESUMO

This study aimed to evaluate the effects of two different structural alcohol permeation enhancers (menthol and propylene glycol) on the internal structure and in vitro properties of the dual drug-loaded lyotropic liquid crystalline (LLC) gels. The LLC gels were prepared and characterized by polarized light microscopy, small-angle X-ray scattering, differential scanning calorimetry, attenuated total reflectance-Fourier transform infrared spectrum, and rheology. Based on the results, the inner structure of the gels was QII mesophase and exhibited a pseudoplastic fluid behavior. The level of internal order in the LLC mesophase would be affected by introduced 2 wt% menthol (MEN) and propylene glycol (PG). The in vitro release experiment showed that the release behavior of sinomenine hydrochloride (SH) and cinnamaldehyde (CA) from the LLC system was dominated by Fickian diffusion (n < 0.43). MEN and PG had the opposite effects on the release of hydrophilic SH, while the MEN and PG both increased the release of lipophilic drug CA. Furthermore, in vitro permeation studies indicated that MEN and PG could both improve the skin permeability of SH and CA, and MEN displayed more pronounced enhancement. All the samples showed no skin irritation on the normal rat skin. Collectively, in our research, monoterpenoid MEN exhibited a better penetration-promoting effect than straight-chain fatty alcohol PG on the dual drug-loaded LLC system.


Assuntos
Acroleína/análogos & derivados , Sistemas de Liberação de Medicamentos , Cristais Líquidos/química , Mentol/química , Morfinanos/química , Propilenoglicol/química , Acroleína/química , Administração Cutânea , Animais , Liberação Controlada de Fármacos , Feminino , Géis/química , Masculino , Ratos , Ratos Sprague-Dawley
6.
AAPS PharmSciTech ; 21(3): 84, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31989358

RESUMO

The purpose of this study was to compare the pharmacokinetics and tissue distribution of ibuprofen (IBU) gel in female rats after transdermal administration through the skin of the abdomen and back. IBU was used as the model drug to prepare carbomer gel. After the abdominal and back administration, the concentration of IBU in rat plasma was detected by high-performance liquid chromatography (HPLC). Besides, the contents of IBU in the uterus, heart, liver, spleen, lung, and kidney were detected, respectively, to clarify the distribution characteristics in vivo. Through abdominal route, the AUC0- ∞ (area under the concentration-time curve from time zero to infinity) of uterus was 424.75 µg/g h, which is 3.60 times higher than that of plasma, and was significantly higher than that of other tissues (P < 0.0001). Tmax (peak time) of uterus and plasma was 4 h and 2 h, respectively. Upon transdermal application of IBU to the back, the AUC0-∞ of uterus was 75.47 µg/g h, which is 12.63 times lower than that of plasma, while Tmax of uterus and plasma was not lower than 20 h. These results indicated that IBU entered the blood circulation through abdominal administration in a small amount and mainly of the drug entered the uterus, while IBU entered the blood circulation and redistributed to tissues after absorption through the dorsal skin slowly. IBU could effectively reach the uterus and have a certain targeting through abdominal administration, which provides a prospect for clinical transdermal administration in the treatment of dysmenorrhea.


Assuntos
Ibuprofeno/administração & dosagem , Administração Cutânea , Animais , Feminino , Géis , Ibuprofeno/farmacocinética , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
7.
Clin Endocrinol (Oxf) ; 90(5): 753-765, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30776142

RESUMO

OBJECTIVE: Handgrip strength (HGS) begins an accelerating decline around 50 years. Many of the studies performed in old adults have demonstrated a significant relationship between vitamin D and HGS, but the studies performed in participants with a broad age range have yielded conflicting results. The purpose of the study was to investigate the relationship between vitamin D and HGS using age 50 as a specific cut-off. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Totally 5102 participants (2911 males, 2191 females) from the TCLSIH Cohort. MEASUREMENTS: Serum concentration of 25-hydroxyvitamin D (25(OH)D) was measured using an enzyme immunoassay. We divided participants into quartiles according to 25(OH)D, and the ranges for increasing quartiles were as follows: (males [≥50 years]: 10.94-31.85, 31.88-43.01, 43.20-56.06, 56.20-143.0; males [<50 years]: 11.11-34.68, 34.71-46.91, 46.96-59.45, 59.50-143.7; females [≥50 years]: 7.21-30.01, 30.02-40.18, 40.21-52.44, 52.49-275.4; females [<50 years]: 5.29-28.91, 28.92-40.19, 40.20-51.90, 51.91-140.2). HGS was measured with a hydraulic hand-held dynamometer. Analysis of covariance was employed to explore the relationship. RESULTS: Among males aged above 50 years, the means (95% confidence interval) for HGS per body weight across the categories of serum 25(OH)D concentration were 0.523 (0.430-0.638), 0.545 (0.447-0.664), 0.543 (0.446-0.661), 0.546 (0.449-0.664) (Ptrend  < 0.01) after adjustment for potential confounding factors. However, no relationships were observed between serum 25(OH)D concentration and HGS in males aged below 50 years and females in the whole age range. CONCLUSIONS: Serum 25(OH)D concentration was significantly related to HGS in males aged above 50 years, independent of confounding factors. Future studies are needed to clarify the age and sex relationship between serum 25(OH)D concentration and HGS.


Assuntos
Envelhecimento/fisiologia , Força da Mão/fisiologia , Vitamina D/análogos & derivados , Envelhecimento/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vitamina D/sangue
8.
Nutr Metab Cardiovasc Dis ; 29(9): 916-922, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31377185

RESUMO

BACKGROUND AND AIMS: Metabolic syndrome (MetS) is a combination of metabolic disorders that increase the risk of developing cardiovascular disease, and inflammation is considered as a pathological basis for MetS. Immunoglobulins (Igs) are the major secretory products of the adaptive immune system. However, no large-scale population study has focused on a possible relationship between Igs and MetS. We designed a cross-sectional study to investigate the relationship between Igs and prevalence of MetS in a large-scale adult population. METHODS AND RESULTS: A total of 10,289 participants were recruited among residents in Tianjin, China. Metabolic syndrome was defined in accordance with the criteria of the American Heart Association scientific statements of 2009. Serum levels of Igs were determined by immunonephelometry. Multiple logistic regression models were used to assess the relationship between the quintiles of serum levels of Igs and the prevalence of MetS. The overall prevalence of MetS was 36.1%. The mean (standard deviation) values of Igs (IgG, IgE, IgM, and IgA) were 1205.7 (249.3) mg/dL, 93.1 (238.9) IU/mL, 105.7 (57.3) mg/dL, and 236.2 (97.6) mg/dL, respectively. The adjusted odds ratios (95% confidence interval) of MetS for the highest quintile of Igs (IgG, IgE, IgM, and IgA), when compared to the lowest quintile, were 0.81 (0.70, 0.95), 0.97 (0.83, 1.12), 1.13 (0.97, 1.33), and 1.52 (1.30, 1.77), respectively. CONCLUSIONS: This study demonstrated that decreased IgG and increased IgA are independently related to a higher prevalence of MetS. The results indicate that the Igs might be useful predictive factors for MetS in the general adult population.


Assuntos
Imunoglobulina A/sangue , Imunoglobulina G/sangue , Síndrome Metabólica/sangue , Biomarcadores/sangue , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/imunologia , Pessoa de Meia-Idade , Prevalência , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco
9.
J Chem Phys ; 150(20): 204114, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31153203

RESUMO

One of the fundamental problems relating to the properties of hydrogen is that of insulator-metal transition. Recent theoretical and experimental studies show that the metallization in liquid hydrogen could be a first-order phase transition and involve molecular to atomic transition. However, the location of the critical point is still an unresolved question. Earlier studies reported the critical point at a temperature of 1500-2000 K, but recent experimental observations on diamond-anvil cells show that the discontinuous transition still persists at temperatures well above 2000 K. We have carried out a detailed study on the liquid-liquid phase transition in dense hydrogen by uisng ab initio molecular dynamics simulations and found new evidence for the abrupt metallization between weakly dissociated and strongly dissociated fluid phases at temperatures as high as 3000 and 4000 K. Also, the predicted phase boundary is in excellent agreement with the recent experiments. Our results suggest that this first-order transition in liquid hydrogen likely ends in a critical point around 4000 K, which is significantly higher than the previous theoretical predictions.

10.
Drug Dev Ind Pharm ; 45(12): 1879-1888, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31672067

RESUMO

The goal of this paper was to develop and evaluate dual component-loaded with the hydrophilic sinomenine hydrochloride (SH) and lipophilic cinnamaldehyde (CA) cubic liquid crystal gels for transdermal delivery. The gels was prepared with a vortex method using phytantriol/water (70:30, w/w) and characterized by polarized light microscopy, small-angle X-ray scattering and rheology. The inner structure of the gels were Pn3m cubic phase and exhibited a pseudoplastic fluid behavior. Furthermore, the in vitro release profile showed that the release behavior of the two drugs from cubic liquid crystal gels conformed to Higuchi equation and were dominated by Fick's diffusion (n < 0.45). The ex vivo penetration experiment indicated that dual components-loaded liquid crystal gels can enhance and extend the skin permeation of these two drugs, especially the ratio of SH to CA is 1: 0.5. Finally, transdermal mechanisms were evaluated using laser scanning confocal microscopy and attenuated total reflectance-fourier transform infrared, hinting that hydrophilic and lipophilic drugs weaken each other's transdermal velocity at the initial stage of penetration. In short, the dual drug-loaded liquid crystal gels was a promising strategy for transdermal applications in treatment of chronic disease.


Assuntos
Antirreumáticos/administração & dosagem , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Cristais Líquidos/química , Acroleína/administração & dosagem , Acroleína/análogos & derivados , Acroleína/farmacocinética , Administração Cutânea , Animais , Antirreumáticos/farmacocinética , Artrite Reumatoide/tratamento farmacológico , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Liberação Controlada de Fármacos , Álcoois Graxos/química , Géis , Interações Hidrofóbicas e Hidrofílicas , Masculino , Morfinanos/administração & dosagem , Morfinanos/farmacocinética , Ratos , Pele/metabolismo , Água/química
11.
AAPS PharmSciTech ; 20(1): 32, 2019 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-30603986

RESUMO

The purpose of this paper was to investigate the potential of liquid crystalline (LC) gels for ophthalmic delivery, so as to enhance the bioavailability of pilocarpine nitrate (PN). The gels were prepared by a vortex method using phytantriol and water (in the ratio of 73:27 w/w). Their inner structures were confirmed by crossed polarized light microscopy, small-angle X-ray scattering, attenuated total reflectance-Fourier transform infrared spectrum, and rheology. The in vitro release studies revealed that PN could keep sustained release from the gels over a period of 12 h. The ex vivo apparent permeability coefficient of the gels demonstrated a 3.83-folds (P < 0.05) increase compared with that of eye drops. The corneal hydration levels of the gel maintained in the normal range of 79.46 ± 2.82%, hinting that the gel could be considered non-damaging and safe to the eyes. Furthermore, in vivo residence time evaluation suggested that a better retention performance of LC gel was observed in rabbit's eyes compared to eye drops. In vivo ocular irritation study indicated that LC gel was nonirritant and might be suitable for various eye applications. In conclusion, LC gels might represent a potential ophthalmic delivery strategy to overcome the limitations of eye drops.


Assuntos
Córnea/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Álcoois Graxos/administração & dosagem , Cristais Líquidos , Mióticos/administração & dosagem , Pilocarpina/administração & dosagem , Administração Oftálmica , Animais , Córnea/metabolismo , Álcoois Graxos/metabolismo , Géis , Masculino , Mióticos/metabolismo , Soluções Oftálmicas/administração & dosagem , Soluções Oftálmicas/metabolismo , Permeabilidade/efeitos dos fármacos , Pilocarpina/metabolismo , Coelhos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Água/química
12.
J Chem Phys ; 143(17): 174506, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26547175

RESUMO

An investigation on many-body effects of solid argon at high pressure was conducted based on a many-body expansion of interaction energy. The three- and four-body terms in the expansion were calculated using the coupled-cluster method with single, double, and noniterative triple theory and incremental method, in which the configurations of argon trimers and tetramers were chosen as the same as those in the actual lattice. The four-body interactions in compressed solid argon were estimated for the first time, and the three-body interaction ab initio calculations were extended to a small distance. It shows that the four-body contribution is repulsive at high densities and effectively cancels the three-body lattice energy. The dimer potential plus three-body interaction can well reproduce the measurements of equation of state at pressure approximately lower than ∼60 GPa, when including the four-body effects extends the agreement up to the maximum experimental pressure of 114 GPa.

13.
Nanoscale ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39267610

RESUMO

Two-dimensional room-temperature Janus ferrovalley semiconductors with valley polarization and piezoelectric polarization offer new perspectives for designing multifunctional nanodevices. Herein, using first-principles calculations, we predict that the Janus 2H-ZrTeI monolayer is an intrinsic ferromagnetic semiconductor with in-plane magnetic anisotropy and a Curie temperature of 111 K. The Janus ZrTeI monolayer possesses a significant valley polarization of 141 meV due to time-reversal and inversion symmetry breaking. Based on the valley-contrasting Berry curvature, the anomalous valley Hall effect can be observed under an in-plane electric field. Meanwhile, the breaking of the inversion symmetry and mirror symmetry results in large longitudinal and transverse piezoelectric coefficients. By applying biaxial strain, the Janus 2H-ZrTeI monolayer can also be transformed into a Weyl nodal line semimetal. Furthermore, bilayers of ZrTeI with AB and BA stacking configurations allow the coexistence of valley polarization and ferroelectricity, enabling the manipulation of magnetism, ferroelectric polarization, and valley polarization through interlayer sliding. Our work provides a platform for studying valley polarization, piezoelectricity, and multiferroic coupling, which is significant for the application of multifunctional devices.

14.
J Biomater Sci Polym Ed ; 34(14): 2021-2039, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37089114

RESUMO

Primary dysmenorrhea is a common disease in women, and oral administration of Ibuprofen (IBU) is associated with first-pass effects and gastrointestinal irritation. Here, we developed ibuprofen-loaded hexagonal liquid crystal (IBU HLC) gel for transdermal administration. In this study, the structure of prepared IBU HLC was characterized using polarizing microscopey (PLM) and small angle X ray diffraction (SAXS). In vitro drug release behavior and percutaneous penetration were investigated, and drug transdermal behavior was observed by confocal laser scanning microscope (CLSM). Finally, the pharmacokinetic profile and tissue distribution were investigated after transdermal administration. The PLM and SAXS results showed that the inner structure of IBU HLC was hexagonal phase. Moreover, in vitro release, skin permeation and CLSM demonstrated that IBU HLC had an excellent sustained-release effect, and a good transdermal penetration effect accompanied by the combination of multiple percutaneous routes. Pharmacokinetic studies indicated that IBU entered the blood circulation through abdominal transdermal administration in small amounts, mainly entering the uterus, and had a certain targeting ability. In conclusion, the IBU HLC gel would be a promising sustained-release preparation for transdermal administration to relieve dysmenorrhea with a significant drug concentration in the uterus.


Assuntos
Ibuprofeno , Cristais Líquidos , Feminino , Humanos , Administração Cutânea , Dismenorreia/tratamento farmacológico , Espalhamento a Baixo Ângulo , Difração de Raios X , Útero
15.
J Chem Phys ; 137(4): 044108, 2012 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-22852598

RESUMO

The importance of the four-body contribution in compressed solid krypton was first evaluated using the many-body expansion method and the coupled cluster theory with full single and double excitations plus perturbative treatment of triples. All different four-atom clusters existing in the first- and second-nearest neighbor shells of face-centered cubic krypton were considered, and both self-consistent-field Hartree-Fock and correlation parts of the four-body interaction were accurately determined from the ambient conditions up to eightfold volume compression. We find that the four-body interaction energy is negative at compression ratio lower than 2, where the dispersive forces play a dominant role. With increasing the compression, the four-body contribution becomes repulsive and significantly cancels the over-softening effects of the three-body potential. The obtained equation of state (EOS) was compared with the experiments and the density-functional theory calculations. It shows that combination of the four-body effects with two- and three-body interactions leads to an excellent agreement with EOS measurements throughout the whole experimental range 0-130 GPa, and extends the prediction to 300 GPa.

16.
Int J Pharm ; 614: 121461, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35026310

RESUMO

Self-emulsifying drug delivery systems (SEDDS) have potential applications in the delivery of hydrophobic components. Oral drugs are readily captured and cleared by intestinal mucus, a natural barrier that covers the mucosal epithelium and prevents the entry of foreign substances. In this study, we investigated for the first time the ability of SEDDS to deliver the lipophilic aldehyde cinnamaldehyde (CA-SEDDS) in rat mucus, mucin solution, Caco-2 and Caco-2/HT29 co-culture monolayer systems. CA-SEDDS was characterized by particle size, Zeta potential and the logDSEDDS/release medium. The capacity of CA-SEDDS to enhance mucus permeability was investigated in rat intestinal mucus gel and mucin solution with the period of in 12 h by Transwell® diffusion. We evaluated the potential of CA-SEDDS delivery of CA in a co-culture system of absorptive Caco-2 and mucus-secreting HT29 cells. CA-SEDDS exhibited excellent mucus permeability in mucus and mucin solutions, 5.1- and 2.8-fold higher than the free CA group, respectively. CA-SEDDS penetration increased by 2.5-fold compared with free CA when using the mucus-secreting co-culture cell model as a barrier. The relative oral bioavailability of CA-SEDDS was 242% compared to CA without formulation. These findings suggest that SEDDS exhibited good release and superior mucus permeability, displaying great potential for the future of hydrophobic oral applications.


Assuntos
Sistemas de Liberação de Medicamentos , Muco , Acroleína/análogos & derivados , Animais , Células CACO-2 , Técnicas de Cocultura , Emulsões , Humanos , Ratos
17.
J Phys Condens Matter ; 33(1): 015401, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-32932242

RESUMO

The properties of dense hot hydrogen, in particular the phase transition between the molecular insulating and atomic conductive states, are important in the fields of astrophysics and high-pressure physics. Previous ab initio calculations suggested the metallization in liquid hydrogen, accompanied by dissociation, is a first-order phase transition and ends at a critical point in temperature range between 1500 and 2000 K and pressure close to 100 GPa. Using density functional theoretical molecular dynamics simulations, we report a first-principles equation of state of hydrogen that covers dissociation transition conditions at densities ranging from 0.20 to 1.00 g/cc and temperatures of 600-9000 K. Our results clearly indicate that a drop in pressure and a sharp structural change still occur as the system transforms from a diatomic to monoatomic phase at temperatures above 2000 K, and support the first-order phase transition in liquid hydrogen would end in the temperature about 4500 K.

18.
J Chromatogr Sci ; 59(7): 606-617, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33969409

RESUMO

OBJECTIVE: Sinomenii Caulis (QingFengTeng) and Ramulus Cinnamomi (GuiZhi) are traditional Chinese drugs that have been used for anti-inflammation. In this study, the team plans to find out the material basis of a Chinese herb combination composed of the two herbs with different ratios. METHODS: The extracts of the herbal compound with various ratios obtained from ethanol extraction were analyzed by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) and gas chromatography coupled mass spectrometry to identify the basic chemical compounds. Simultaneously, the contents of the eight main components (sinomenine, magnoflorine, laurifoline, dauricine, coumarin, cinnamyl alcohol, cinnamic acid and cinnamaldehyde) from herb formula were determined by gradient elution by high-performance liquid chromatography. Furthermore, the content of sinomenine and cinnamaldehyde were determined by isocratic elution, respectively. RESULTS: Eighteen compounds in the herb formula were identified by UHPLC-Q-TOF-MS. The components in the GuiZhi are mostly volatile oils and the kinds of compounds isolated from the formula in the ratio of 4:1 were the most. Wherein eight compounds were identified as the main detection targets in the content determination. CONCLUSION: The extraction rate of sinomenine in QingFengTeng was related to the proportion of GuiZhi in the drug pairs. Synchronously, the addition of sinomenine in different proportions also had some influence on the extraction of cinnamaldehyde in GuiZhi. Furthermore, the series of methods was successfully applied to the simultaneous determination of chemical compounds in different samples of QingFengTeng-GuiZhi decoction.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas , Cromatografia Gasosa-Espectrometria de Massas/métodos , Acroleína/análogos & derivados , Acroleína/análise , Acroleína/química , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Morfinanos/análise , Morfinanos/química , Óleos Voláteis/química
19.
Int J Pharm ; 599: 120415, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33647411

RESUMO

Mucus is widely disseminated in the nasal cavity, oral cavity, respiratory tract, eyes, gastrointestinal tract, and reproductive tract to prevent the invasion of pathogenic bacteria and toxins. The mucus layer through its continuous secretion can prevent the passage of macromolecular substances such as pathogenic bacteria and toxins, thereby reducing the occurrence of inflammation. Without a doubt, mucus also hinders oral absorption. The physiological and biochemical properties of intestinal mucus and the different types of mucus barrier models need to be predominated. To find ways to increase the bioavailability of drugs in the future, this article summarizes mucus composition, barrier properties, mucus models, and mucoadhesive/mucopenetrating particles to highlight the information they can afford. Collectively, the review seeks to provide a state-of-the-art roadmap for researchers who must contend with this critical barrier to drug delivery.


Assuntos
Preparações Farmacêuticas , Disponibilidade Biológica , Difusão , Sistemas de Liberação de Medicamentos , Muco
20.
Plant Physiol Biochem ; 151: 400-410, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32278958

RESUMO

Cymbidium faberi Rolfe (Orchidaceae) is an herbaceous plant native to China, where it has a long history of cultivation owing to its beautiful flower pattern and floral fragrance. Previously, we conducted a transcriptome analysis of the flower and vegetative buds to elucidate the mechanisms of flower development in C. faberi. In the present study, we found nine secondary metabolic pathways through the KEGG pathway database that were related to the biosynthesis of methyl jasmonate (MeJA) and other volatile organic compounds. qRT-PCR was performed to analyze the expression levels of four key genes in the MeJA pathway. Among these, CfJMT (jasmonic acid carboxyl methyltransferase) had higher transcript levels in sepals, petals and labella than in other tissues. CfJMT was cloned from the petals of full-bloom flowers of C. faberi. The predicted CfJMT protein sequence contains conserved jasmonic acid methyl transferase-7 domains, indicating that it belongs to the SABATH protein family. The CfJMT coding sequence driven by the CaMV35S promoter was successfully transformed into Petunia hybrida through an Agrobacterium-mediated method. Although MeJA could not be detected in either wild-type or transgenic petunia plants, the leaves of the transgenic plants were smaller than those of wild-type plants and pollen development was abnormal. These results indicate that heterologous expression of CfJMT may change the levels of endogenous jasmonic acid and other hormones, but that the content of MeJA is not increased significantly by transformation with CfJMT alone. Thus, other related genes and regulation factors may play important roles in this process.


Assuntos
Acetatos , Ciclopentanos , Regulação da Expressão Gênica de Plantas , Orchidaceae , Oxilipinas , Petunia , Acetatos/metabolismo , China , Ciclopentanos/metabolismo , Flores/genética , Genes de Plantas/genética , Orchidaceae/genética , Orchidaceae/metabolismo , Oxilipinas/metabolismo , Petunia/genética , Petunia/metabolismo
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