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1.
J Microencapsul ; 41(3): 157-169, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38451031

RESUMO

OBJECTIVE: To investigate the transdermal mechanisms and compare the differences in transdermal delivery of Sinomenine hydrochloride (SN) between solid lipid nanoparticles (SLN), liposomes (LS), and nanoemulsions (NE). METHODS: SN-SLN, SN-LS and SN-NE were prepared by ultrasound, ethanol injection and spontaneous emulsification, respectively. FTIR, DSC, in vitro skin penetration, activation energy (Ea) analysis were used to explore the mechanism of drug penetration across the skin. RESULTS: The particle size and encapsulation efficiency were 126.60 nm, 43.23 ± 0.48%(w/w) for SN-SLN, 224.90 nm, 78.31 ± 0.75%(w/w) for SN-LS, and 83.22 nm, 89.01 ± 2.16%(w/w) for SN-LS. FTIR and DSC showed the preparations had various levels of impacts on the stratum corneum's lipid structure which was in the order of SLN > NE > LS. Ea values of SN-SLN, SN-LS, and SN-NE crossing the skin were 2.504, 1.161, and 2.510 kcal/mol, respectively. CONCLUSION: SLN had a greater degree of alteration on the skin cuticle, which allows SN to permeate skin more effectively.


Assuntos
Morfinanos , Nanopartículas , Absorção Cutânea , Portadores de Fármacos/química , Administração Cutânea , Pele/metabolismo , Nanopartículas/química , Lipídeos/química , Tamanho da Partícula
2.
J Transl Med ; 21(1): 302, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147666

RESUMO

BACKGROUND: Epithelial-to-mesenchymal transition (EMT) and cancer stem-like cells (CSLCs) play crucial role in tumor metastasis and drug-resistance. Disheveled3 (DVL3) is involved in malignant behaviors of cancer. However, the role and potential mechanism of DVL3 remain elusive in EMT and CSLCs of colorectal cancer (CRC). METHODS: UALCAN and PrognoScan databases were employed to evaluate DVL3 expression in CRC tissues and its correlation with CRC prognosis, respectively. Transwell, sphere formation and CCK8 assay were used to assess metastasis, stemness and drug sensitivity of CRC cells, respectively. Western blotting and dual luciferase assay were performed to analyze the protein expression and Wnt/ß-catenin activation, respectively. Lentiviral transfection was used to construct the stable cell lines. Animal studies were performed to analyze the effect of silencing DVL3 on tumorigenicity and metastasis of CRC cells in vivo. RESULTS: DVL3 was overexpressed in CRC tissues and several CRC cell lines. DVL3 expression was also higher in CRC tissues with lymph node metastasis than tumor tissues without metastasis, and correlated with poor prognosis of CRC patients. DVL3 positively regulated the abilities of migration, invasion and EMT-like molecular changes in CRC cells. Moreover, DVL3 promoted CSLCs properties and multidrug resistance. We further identified that Wnt/ß-catenin was crucial for DVL3-mediated EMT, stemness and SOX2 expression, while silencing SOX2 inhibited DVL3-mediated EMT and stemness. Furthermore, c-Myc, a direct target gene of Wnt/ß-catenin, was required for SOX2 expression and strengthened EMT and stemness via SOX2 in CRC cells. Finally, knockdown of DVL3 suppressed tumorigenicity and lung metastasis of CRC cells in nude mice. CONCLUSION: DVL3 promoted EMT and CSLCs properties of CRC via Wnt/ß-catenin/c-Myc/SOX2 axis, providing a new strategy for successful CRC treatment.


Assuntos
Neoplasias Colorretais , Proteínas Desgrenhadas , Transição Epitelial-Mesenquimal , Via de Sinalização Wnt , beta Catenina , Animais , Camundongos , beta Catenina/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Humanos , Proteínas Desgrenhadas/genética , Células-Tronco Neoplásicas
3.
Inorg Chem ; 62(17): 6537-6543, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37074131

RESUMO

In the past decades, many supramolecular cages with different sizes and shapes have been achieved through coordination-driven self-assembly. However, the strategy of topology adjustment by using a steric hindrance effect has not been fully developed. In this Article, we report the synthesis of ligand LA with rotatable arms, ligand LB with restricted arms, and their precisely controlled self-assembly to tetramer cage T1 and dimer cage D1, respectively, under the same conditions. By utilizing the steric hindrance of the ligands, the shapes and sizes of metallosupramolecular cages have been successfully adjusted. The metallocages were characterized by NMR spectroscopy (1H, 13C, COSY, NOESY, and DOSY), mass spectrometry (ESI-MS, TWIM-MS), transmission electron microscopy, and atomic force microscopy. This synthetic method would have the potential to be a general strategy for the design and self-assembly of diverse cages with tunable shape, size, and applicable properties.

4.
Inorg Chem ; 62(29): 11500-11509, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37436175

RESUMO

Supramolecular architectures with multiple emissive units are especially appealing due to their desired properties, such as artificial light harvesting and white-light emission. But fully achieving multi-wavelength photoluminescence in a single supramolecular architecture remains a challenge. In this paper, functionalized supramolecular architectures containing twelve metal centers and six pyrene moieties were nearly quantitatively synthesized by multi-component self-assembly and fully characterized by 1D and 2D nuclear magnetic resonance, dynamic light scattering, electrospray ionization mass spectrometry, traveling-wave ion mobility mass spectrometry, and transmission electron microscopy. Moreover, the hierarchical nano-assemblies were prepared by introducing anionic dyes to the positively charged self-assembled framework, which contained three luminescence centers, namely, pyrene, tpy-Cd coordination parts, and Sulforhodamine B anions. Such a hierarchically assembled system displayed tunable emission by taking full advantage of aggregation-induced emission enhancement, aggregation-caused quenching, and fluorescence resonance energy transfer effects and showed the diverse emission colors. This research provides a new insight for constructing multiple emissive metallo-supramolecular assemblies.

5.
J Acoust Soc Am ; 151(3): 1804, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35364939

RESUMO

The aviation sector is rapidly evolving with more electric propulsion systems and a variety of new technologies of vertical take-off and landing manned and unmanned aerial vehicles. Community noise impact is one of the main barriers for the wider adoption of these new vehicles. Within the framework of a perception-driven engineering approach, this paper investigates the relationship between sound quality and first order physical parameters in rotor systems to aid design. Three case studies are considered: (i) contra-rotating versus single rotor systems, (ii) varying blade diameter and thrust in both contra-rotating and single rotor systems, and (iii) varying rotor-rotor axial spacing in contra-rotating systems. The outcomes of a listening experiment, where participants assessed a series of sound stimuli with varying design parameters, allow a better understanding of the annoyance induced by rotor noise. Further to this, a psychoacoustic annoyance model optimised for rotor noise has been formulated. The model includes a novel psychoacoustic function to account for the perceptual effect of impulsiveness. The significance of the proposed model lies in the quantification of the effects of psychoacoustic factors, such as loudness as the dominant factor, and also tonality, high frequency content, temporal fluctuations, and impulsiveness on rotor noise annoyance.


Assuntos
Ruído , Som , Estimulação Acústica , Percepção Auditiva , Humanos , Ruído/efeitos adversos , Psicoacústica
6.
J Am Chem Soc ; 143(6): 2537-2544, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33378184

RESUMO

Nanosized cage-within-cage compounds represent a synergistic molecular self-assembling form of three-dimensional architecture that has received particular research focus. Building multilayered ultralarge cages to simulate complicated virus capsids is believed to be a tough synthetic challenge. Here, we synthesize two large double-shell supramolecular cages by facile self-assembly of presynthesized metal-organic hexatopic terpyridine ligands with metal ions. Differing from the mixture of prisms formed from the inner tritopic ligand, the redesigned metal-organic hexatopic ligands bearing high geometric constraints that led to the exclusive formation of discrete double-shell structures. These two unique nested cages are composed of inner cubes (5.1 nm) and outer huge truncated cubes (12.0 and 13.2 nm) with six large bowl-shape subcages distributed on six faces. The results with molecular weights of 75 232 and 77 667 Da were among the largest synthetic cage-in-cage supramolecules reported to date. The composition, size and shape were unambiguously characterized by a combination of 1H NMR, DOSY, ESI-MS, TWIM-MS, TEM, AFM, and SAXS. This work provides an interesting model for functional recognition, delivery, and detection of various guest molecules in the field of supramolecular materials.

7.
J Acoust Soc Am ; 149(2): 835, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33639829

RESUMO

Unmanned aerial vehicle (UAV) technologies are rapidly advancing due to the unlimited number of applications from parcel delivery to people transportation. As the UAV market expands, community noise impact will become a significant problem for public acceptance. Compact drone architectures based on contra-rotating propellers bring significant benefits in terms of aerodynamic performance and redundancy to ensure vehicle control in case of component failure. However, contra-rotating propellers are severely noisy if not designed appropriately. In the framework of a perception-influenced design approach, this paper investigates the optimal rotor spacing distance configuration to minimise noise annoyance. On the basis of a series of psychoacoustic metrics (i.e., loudness, fluctuation strength, roughness, sharpness, and tonality) and psychoacoustic annoyance (PA) models, the optimal rotor axial separation distance (expressed as a function of propeller blade diameter) is at a range from 0.2 to 0.4. This paper also discusses the performance of currently available psychoacoustic models to predict propeller noise annoyance and defines further work to develop a PA model optimised for rotating systems.

8.
J Am Chem Soc ; 142(17): 7987-7994, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32274928

RESUMO

The artificial synthesis of giant, three-dimensional, and shell-like architectures with growing complexity and novel functionalities is an especially challenging task for chemists. Fullerenes and self-assembled cages are remarkable examples that are proven milestones in the field of functional materials. Herein, we present another unique system: a giant terpyridine-based truncated metallo-tetrahedral architecture that includes densely-packed ionic pairs with a significant internal cavity. This huge metallo-tetrahedron with a molecular weight up to 70 000 Da was self-assembled simultaneously with 64 components: 12 large antler-shaped ligands (5), 4 star-shaped ligands (6), and 48 Cd2+ ions. Surprisingly, the giant tetrahedron shows broad visible emission (400-640 nm) and aggregation induced emission enhancement (AIEE) via a hierarchical assembly into highly-ordered nanoaggregates. A tunable emission color and near white-light emission in mixed solvent systems were also achieved. The present work not only affords an effective approach to the creation of giant shell-like architectures that can be used to mimic biological viruses and chemical frameworks but also provides a new class of functional metallo-architectures.

9.
Inorg Chem ; 59(9): 6640-6645, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32286799

RESUMO

A metal-organic supramolecular nanobelt was synthesized by quantitative self-assembling terpyridine-functionized tetraphenylethylene (TPE) and Cd2+, which only showed a weak emission both in solution or aggregated state. Nevertheless, nanobelt complex could be transferred to a fluorescence turn-on sensor to S2- by taking advantage of the structural transformation from nanobelt to its fluorescent ligand.

10.
Mol Ecol ; 28(15): 3508-3522, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31233652

RESUMO

Seasonal breeding is a universal reproductive strategy in many animals. Hypothalamic genes, especially type 2 and 3 iodothyronine deiodinases (Dio2/3), RFamide-related peptide 3 (Rfrp-3), kisspeptin (Kiss-1) and gonadotropin-releasing hormone (GnRH), are involved in a photoperiodic pathway that encodes seasonal signals from day length in many vertebrate species. However, the seasonal expression patterns of these genes in wild mammals are less studied. Here, we present a four-year field investigation to reveal seasonal rhythm and age-dependent reproductive activity in male Brandt's voles (Lasiopodomys brandtii) and to detect relationships among seasonal expression profiles of hypothalamic genes, testicular activity, age and annual day length. From breeding season (April) to nonbreeding season (October), adult male voles displayed a synchronous peak in gonadal activity with annual day length around summer solstice, which was jointly caused by age structure shifts and age-dependent gonadal development patterns. Overwintered males maintained reproductive activity until late in the breeding season, whereas most newborn males terminated gonadal development completely, except for a minority of males born early in spring. Consistently, the synchronous and opposite expression profiles of Dio2/3 suggest their central function to decode photoperiodic signals and to predict the onset of the nonbreeding season. Moreover, changes in Dio2/3 signals may guide the actions of Kiss-1 and Rfrp-3 to regulate the age-dependent divergence of reproductive strategy in wild Brandt's vole. Our results provide evidence on how hypothalamic photoperiod genes regulate seasonal breeding in a natural rodent population.


Assuntos
Arvicolinae/genética , Cruzamento , Regulação da Expressão Gênica no Desenvolvimento , Hipotálamo/metabolismo , Estações do Ano , Envelhecimento/genética , Animais , Masculino , Tamanho do Órgão/genética , Fotoperíodo , Testículo/embriologia , Testículo/metabolismo
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 Biomed Inform ; 83: 1-9, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29746916

RESUMO

Since identifying relations between chemicals and diseases (CDR) are important for biomedical research and healthcare, the challenge proposed by BioCreative V requires automatically mining causal relationships between chemicals and diseases which may span sentence boundaries. Although most systems explore feature engineering and knowledge bases to recognize document level CDR relations, feature learning automatically is limited only in a sentence. In this work, we proposed an effective model that automatically learns document level semantic representations to extract chemical-induced disease (CID) relations from articles by combining advantages of convolutional neural network and recurrent neural network. First, to purposefully collect contexts, candidate entities existing in multiple sentences of an article were masked to make the model have ability to discern candidate entities and general terms. Next, considering the contiguity and temporality among associated sentences as well as the topic of an article, a hierarchical network architecture was designed at the document level to capture semantic information of different types of text segments in an article. Finally, a softmax classifier performed the CID recognition. Experimental results on the CDR corpus show that the proposed model achieves a good overall performance compared with other state-of-the-art methods. Although only using two types of embedding vectors, our approach can perform well for recognizing not only intra-sentential but also inter-sentential CID relations.


Assuntos
Distúrbios Induzidos Quimicamente/classificação , Mineração de Dados/métodos , Redes Neurais de Computação , Causalidade , MEDLINE , Publicações
13.
AAPS PharmSciTech ; 19(2): 858-865, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29027137

RESUMO

In situ gels containing sinomenine hydrochloride (SMH) for intra-articular (IA) administration to treat rheumatoid arthritis (RA) were designed and investigated in this study. Glycerol monooleate (GMO) was used due to the potential to generate viscous crystalline phase structures upon water absorption. The gels were evaluated using different parameters: syringeability, gelation, viscosity, and drug release. And, polarized light microscopy (PLM), small-angle X-ray scattering investigation (SAXS), and rheological studies were used to analyze their internal structures. In vitro drug release studies were performed by the dialysis membrane diffusion method. The syringeability, viscosity, gelation time, and water for gelation of the obtained preparation met the requirements of IA injection. PLM, SAXS, and rheological analysis showed that all samples had transformed from flowable isotropic solution phases to the inverse cubic (V2) phases upon excess water. And, the gels were found to be able to maintain the drug release for more than 1 week. Results showed that in situ gels based on GMO liquid crystalline could provide a sustained system for SMH. Due to its sustained release, the in situ cubic gels were suitable for IA injection to treat RA.


Assuntos
Glicerídeos/química , Cristais Líquidos/química , Difusão , Liberação Controlada de Fármacos , Géis/química , Glicerídeos/administração & dosagem , Glicerídeos/farmacocinética , Injeções Intra-Articulares , Reologia , Espalhamento a Baixo Ângulo , Viscosidade , Difração de Raios X/métodos
14.
AAPS PharmSciTech ; 19(5): 2237-2246, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29740759

RESUMO

This study developed a new transdermal delivery system for the improved delivery of sinomenine hydrochloride (SH). The delivery system utilized the advantages of lyotropic liquid crystals (LLC) creating an adaptable system that offers a variety of options for the field of transdermal delivery. The formulation was prepared, characterized, and evaluated for its skin penetration in vitro. In the study, the appearance of samples was characterized by visual observation, and these LLC gels were colorless and transparent. Polarizing light microscopy (PLM) and small-angle X-ray diffraction (SAXS) were used to analyze the internal structures of gels, and the gels displayed a cubic double-diamond (Pn3m) internal structure with a dark field of vision. The Franze diffusion cell was used to evaluate its skin penetration. There were several factors which might influence the skin penetration of drugs, such as drug loading, water content, and the layer spacing of the LLC. In our case, drug concentration gradient played a more powerful role. The result of in vitro permeation studies demonstrated that the drug concentration was higher; the cumulative osmotic quantity of SH (Q) was greater. Therefore, the system was a promising formulation for successful percutaneous delivery of SH through the skin.


Assuntos
Sistemas de Liberação de Medicamentos , Cristais Líquidos/química , Morfinanos/química , Administração Cutânea , Animais , Morfinanos/farmacocinética , Permeabilidade , Ratos , Espalhamento a Baixo Ângulo , Pele/metabolismo
15.
AAPS PharmSciTech ; 19(5): 2023-2040, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29869308

RESUMO

Liquid crystals (LCs) are conventionally divided into thermotropic or lyotropic, based on the organization and sequence of the controlled molecular system. Lipid-based lyotropic liquid crystal (LLC), such as lamellar (Lα), bicontinuous cubic (QII), or hexagonal (HII) phases, have attracted wide interest in the last few decades due to their practical potential in diverse applications and notable structural complexity. Various guest molecules, such as biopharmaceuticals, chemicals, and additives, can be solubilized in either aqueous or oily phase. And the LLC microstructure can be altered to affect the rate of drug release eventually. To utilize these microstructural variations to adjust the drug release in drug delivery system (DDS), it is crucial to understand the structure variations of the LLC caused by different types of guest molecules. Therefore, in this article, we review the effect of guest molecules on lipid-based LLC microstructures. In particular, we focus on the different characterization methods to evaluate this change caused by guest substances, such as polarized light microscopy (PLM), small-angle X-ray scattering (SAXS), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), self-diffusion nuclear magnetic resonance (SD-NMR), and so on.


Assuntos
Química Farmacêutica , Cristais Líquidos/química , Animais , Biofarmácia , Sistemas de Liberação de Medicamentos , Humanos
16.
Zhongguo Zhong Yao Za Zhi ; 43(12): 2522-2530, 2018 Jun.
Artigo em Zh | MEDLINE | ID: mdl-29950070

RESUMO

Three different kinds of sinomenine in situ liquid crystal were prepared for different prescriptions, to investigate the rheological properties before and after in situ treatment and evaluate its feasibility for embolization. Rheological experiments were carried out with cone plate fixtures. Both the steady-state rheological and non-steady-state rheological properties of in-situ gels and the swelling gels were studied and compared. Steady-state rheological study results showed that all the three liquid embolic agents were non-newtonian fluid before and after in situ treatment, which would become less ropy when they were pressed with shear stress; their viscosities differed by 2-5 orders of magnitude. It had a yield value of about 10 Pa before in situ treatment and about 4 500 Pa after in situ treatment. All the six systems had thixotropy while their dynamic viscosities were not influenced by the shear rate, all less than 0.3 Pa·s before in situ treatment more than 1 Pa·s after in situ treatment, differing by an order of magnitude. The results of temperature sweeping showed a slight decrease with a steady rate in viscosity within the range of 10-50 °C, differing by 3-4 orders of magnitude. The results of unsteady rheology showed that there was no obvious linear viscoelastic region in the three kinds of agents, indicating the properties of liquid. After in situ treatment, their linear viscoelastic range γ<1% (No.3 was 5%), and their elastic modulus G' was larger than the viscous modulus G", indicating the properties of solid. Frequency scanning results showed that for the systems at low frequencies, G">G', system viscosity in a dominant position; while at high frequencies, G'>G", system elasticity in a dominant position. The results of compound viscosity test also proved that the liquid embolic agent in situ can form a cubic liquid crystal (the structure of No. 3 was destroyed after in situ treatment). The DHR-2 rheometer was used to investigate the rheological properties of in situ gels with three different prescriptions. The method is simple and the result is reliable, which can provide more theoretical reference for the in vitro evaluation and practical application of the product.


Assuntos
Cristais Líquidos , Morfinanos/química , Reologia , Elasticidade , Viscosidade
17.
BMC Bioinformatics ; 18(1): 445, 2017 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-29017459

RESUMO

BACKGROUND: Drug-drug interactions (DDIs) often bring unexpected side effects. The clinical recognition of DDIs is a crucial issue for both patient safety and healthcare cost control. However, although text-mining-based systems explore various methods to classify DDIs, the classification performance with regard to DDIs in long and complex sentences is still unsatisfactory. METHODS: In this study, we propose an effective model that classifies DDIs from the literature by combining an attention mechanism and a recurrent neural network with long short-term memory (LSTM) units. In our approach, first, a candidate-drug-oriented input attention acting on word-embedding vectors automatically learns which words are more influential for a given drug pair. Next, the inputs merging the position- and POS-embedding vectors are passed to a bidirectional LSTM layer whose outputs at the last time step represent the high-level semantic information of the whole sentence. Finally, a softmax layer performs DDI classification. RESULTS: Experimental results from the DDIExtraction 2013 corpus show that our system performs the best with respect to detection and classification (84.0% and 77.3%, respectively) compared with other state-of-the-art methods. In particular, for the Medline-2013 dataset with long and complex sentences, our F-score far exceeds those of top-ranking systems by 12.6%. CONCLUSIONS: Our approach effectively improves the performance of DDI classification tasks. Experimental analysis demonstrates that our model performs better with respect to recognizing not only close-range but also long-range patterns among words, especially for long, complex and compound sentences.


Assuntos
Algoritmos , Interações Medicamentosas , Modelos Teóricos , Redes Neurais de Computação , Bases de Dados como Assunto , Humanos , Publicações , Máquina de Vetores de Suporte
19.
J Nanosci Nanotechnol ; 15(9): 6397-404, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26716193

RESUMO

Camptothecin (CPT) exerts very strong antitumor activities by suppressing the activity of DNA topoisomerase I, but its application is greatly limited owing to its low solubility and the instability of the active lactone form. To overcome this bottleneck, we prepared the novel camptothecin nanocolloids based on N-trimethyl chitosan (CPT-TMC) to efficiently administer CPT systemically. In this study, we investigated the antitumor activity of CPT-TMC against both colon cancer and lung cancer. In vitro cell experiments both CPT and CPT-TMC significantly inhibited the growth of CT26 cells and LL/2 cells, but no statistical difference was observed between CPT-TMC and CPT. In vivo studies, CPT-TMC more effectively inhibited tumor growth and prolonged survival time than CPT both in the CT26 colon carcinoma subcutaneous model and in the LL/2 Lewis lung carcinoma subcutaneous model. In addition, results of PCNA and CD31 immunohistochemical staining of tumor tissues also confirmed the improved antitumor effect of CPT-TMC. These findings suggest that N-trimethyl chitosan could increase the antitumor effect of CPT. Consequently, CPT delivery by N-trimethyl chitosan is a potential approach for effective treatment of cancer.


Assuntos
Antineoplásicos/farmacologia , Camptotecina/farmacologia , Quitosana/química , Portadores de Fármacos/química , Animais , Antineoplásicos/química , Antineoplásicos/toxicidade , Camptotecina/química , Camptotecina/toxicidade , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quitosana/toxicidade , Neoplasias do Colo , Portadores de Fármacos/toxicidade , Feminino , Neoplasias Pulmonares , Camundongos , Camundongos Endogâmicos BALB C
20.
Biomed Chromatogr ; 29(2): 167-75, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24935437

RESUMO

A high-performance liquid chromatography coupled to time-of-flight mass spectrometry (HPLC-TOF MS) method was successfully developed and validated for the identification and determination of seven ginsenosides, Re , Rf , Rb1 , Rc , Rb2 , Ro and Rd , in a Chinese herbal preparation, Shenfu injection, and rat plasma. Based on the method, the pharmacokinetic profiles of the seven ginsenosides were investigated following intravenous administration of single dose of Shenfu injection to six rats. The established method had high linearity, selectivity, sensitivity, accuracy and precision. The pharmacokinetic results showed that Rb1 , Rc and Rb2 had similar pharmacokinetic profiles and relatively long half-life values (19.29 ± 6.36, 29.54 ± 22.91 and 35.60 ± 30.66 h). The half-lives of Rf and Rd were 4.21 ± 3.68 and 8.49 ± 5.20 h, respectively, indicating that they could be metabolized more rapidly than Rb1 , Rc and Rb2 .


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/farmacocinética , Ginsenosídeos/sangue , Espectrometria de Massas em Tandem/métodos , Administração Intravenosa , Animais , Medicamentos de Ervas Chinesas/administração & dosagem , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
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