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1.
Nanomaterials (Basel) ; 14(4)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38392734

RESUMO

Herein, the preparation process, morphology, structure, and magnetic properties of La1.85Sr0.15CuO4 (LSCO) cobweb-like nanofibers are reported. LSCO nanofibers with a regular grain size distribution are successfully prepared via electrospinning, followed by calcination. We conducted morphology analysis and elemental distribution using electron microscopy and energy-dispersive X-ray spectroscopy (EDS), respectively. Additionally, magnetic property testing was performed using a vibrating sample magnetometer (VSM) to confirm the superconducting properties of the samples. Interestingly, our samples exhibited a superconducting transition temperature, Tc, of 25.21 K, which showed some disparity compared to similar works. Furthermore, we observed a ferromagnetic response at low temperatures in the superconducting nanofibers. We attribute these phenomena to the effects generated by surface states of nanoscale superconducting materials.

2.
Curr Drug Targets ; 20(16): 1636-1651, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31362671

RESUMO

BACKGROUND: Hepatitis B is a very harmful and epidemic disease caused by hepatitis B virus (HBV). Although an effective anti-HBV vaccine is available, chronic infection poses still a huge health burden in the whole world. The present anti-HBV drugs including nucleoside analogues and interferonalpha have their limitations without exception. There is no effective drug and therapeutic method that can really and truly cure hepatitis B so far. The variability of HBV genome results in that a significant number of patients develop drug resistance during the long-term use of anti-HBV drugs. Hence, it is urgently needed to discover novel targets and develop new drugs against hepatitis B. OBJECTIVE: The review aims to provide the theory support for designing of the anti-HBV innovative drugs by offering a summary of the current situation of antiviral potential targets. RESULTS AND CONCLUSION: Since HBV is obligate intracellular parasite, and as such it depends on host cellular components and functions to replicate itself. The targeting both virus and host might be a novel therapeutic option for hepatitis B. Accordingly, we analyse the advances in the study of the potential drug targets for anti-HBV infection, focusing on targeting virus genome, on targeting host cellular functions and on targeting virus-host proteins interactions, respectively. Meanwhile, the immune targets against chronic hepatitis B are also emphasized. In short, the review provides a summary of antiviral therapeutic strategies to target virus factors, host factors and immune factors for future designing of the innovative drug against HBV infection.


Assuntos
Antivirais/farmacologia , Antivirais/uso terapêutico , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Animais , Descoberta de Drogas/métodos , Farmacorresistência Viral/efeitos dos fármacos , Farmacorresistência Viral/genética , Genoma Viral/efeitos dos fármacos , Genoma Viral/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Interações entre Hospedeiro e Microrganismos/efeitos dos fármacos , Interações entre Hospedeiro e Microrganismos/genética , Humanos
3.
J Cancer ; 9(9): 1548-1559, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29760792

RESUMO

Hepatocellular carcinoma (HCC) ranks the third leading cause of cancer death in the world and has a notably low survival rate. Circular RNAs (circRNAs) are newly classed non-coding RNA (ncRNA) members that are capable of regulating gene expression at transcription or post-transcription levels. Recent studies demonstrate that some circRNAs are differentially expressed in HCC, and the deregulation of these circRNAs is associated with the clinical pathological and prognostic significance. They also play essential roles in HCC progression, and contribute to cell proliferation, migration, invasion and metastasis by targeting different microRNAs (miRNAs) and protein-coding genes. In this review, we concentrate on recent progress of some important circRNAs in HCC, with an emphasis on their deregulation, functions and regulatory mechanisms, and discuss their potential utility as diagnostic and/or prognostic biomarkers or therapeutic targets for HCC.

4.
Curr Med Chem ; 24(38): 4279-4302, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28814240

RESUMO

BACKGROUND: A great effort has been made to develop efficacious antiviral drugs, but many viral infections are still lack of efficient antiviral therapies so far. The related exploration of natural products to fight viruses has been raised in recent years. Natural compounds with structural diversity and complexity offer a great chance to find new antiviral agents. Particularly, phenolic acids have attracted considerable attention owing to their potent antiviral abilities and unique mechanisms. The aim of this review is to report new discoveries and updates pertaining to antiviral phenolic acids. METHODS: The relevant references on natural phenolic acids were searched. The antiviral phenolic acids were classified according to their structural properties and antiviral types. Meanwhile, the antiviral characteristics and structure-activity relationships of phenolic acids and their derivatives were summarized. RESULTS: The review finds that natural phenolic acids and their derivatives possessed potent inhibitory effects on multiple virus in humans such as human immunodeficiency virus, hepatitis C virus, hepatitis B virus, herpes simplex virus, influenza virus and respiratory syncytial virus. In particular, caffeic acid/gallic acid and their derivatives exhibited outstanding antiviral properties by a variety of modes of action. CONCLUSION: Naturally derived phenolic acids especially caffeic acid/gallic acid and their derivatives may be regarded as novel promising antiviral leads or candidates. Additionally, scarcely any of these compounds has been used as antiviral treatment in clinical practice. Therefore, these phenolic acids with diverse skeletons and mechanisms provide us an excellent resource for finding novel antiviral drugs.


Assuntos
Antivirais/farmacologia , Produtos Biológicos/farmacologia , Hidroxibenzoatos/farmacologia , Viroses/tratamento farmacológico , Antivirais/síntese química , Antivirais/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Humanos , Hidroxibenzoatos/síntese química , Hidroxibenzoatos/química , Estrutura Molecular , Vírus/efeitos dos fármacos
5.
Molecules ; 22(3)2017 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-28272313

RESUMO

Stems are the important residues of Trapa quadrispinosa Roxb., which are abundant in phenolic compounds. Ultrasonic-assisted enzymatic extraction (UAEE) is confirmed as a novel extraction technology with main advantages of enhancing extraction yield and physiological activities of the extracts from various plants. In this study, UAEE was applied to obtain the highest yield of phenolic content, strongest antioxidant, and antitumor activities and to optimize the extraction conditions using response surface methodology (RSM). The extracts from the stems of T. quadrispinosa were characterized by determination of their antioxidant activities through 2,2-azinobis(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS), 1,1-Diphenyl-2-picrylhydrazxyl (DPPH) radical scavenging, total antioxidant capacity (TAC), ferric reducing antioxidant capacity (FRAC) methods and of their antitumor activity by MTT method. The selected key independent variables were cellulase concentration (X1: 1.5%-2.5%), extraction time (X2: 20-30 min) and extraction temperature (X3: 40-60 °C). The optimal extraction conditions for total phenolic content (TPC) value of the extracts were determined as 1.74% cellulase concentration, 25.5 min ultrasonic extraction time and 49.0 °C ultrasonic temperature. Under these conditions, the highest TPC value of 53.6 ± 2.2 mg Gallic acid equivalent (GAE)/g dry weight (DW) was obtained, which agreed well with the predicted value (52.596 mg GAE/g·DW. Furthermore, the extracts obtained from UAEE presented highest antioxidant activities through ABTS, DPPH, TAC and FRAC methods were of 1.54 ± 0.09 mmol Trolox equivalent (TE)/g·DW; 1.45 ± 0.07 mmol·TE/g·DW; 45.2 ± 2.2 mg·GAE/g·DW; 50.4 ± 2.6 µmol FeSO4 equivalent/g·DW and lowest IC50 values of 160.4 ± 11.6 µg/mL, 126.1 ± 10.8 µg/mL, and 178.3 ± 13.1 µg/mL against Hela, HepG-2 and U251 tumor cells, respectively. The results indicated that the UAEE was an efficient alternative to improve extraction yield and enhance the antioxidant and antitumor activities of the extracts. The phenolic extracts from the stems of T. quadrispinosa had significant antioxidant and antitumor activities, which could be used as a source of potential antioxidant and antitumor agents.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Fenóis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Traqueófitas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico , Humanos , Concentração Inibidora 50 , Ondas Ultrassônicas
6.
Fundam Clin Pharmacol ; 28(4): 364-81, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24118072

RESUMO

There are approximately 350 million hepatitis B virus (HBV) carriers worldwide. Chronic HBV infection increases the risk of liver cirrhosis and hepatocellular carcinoma. To date, two classes of antiviral drugs have been approved by the Food and Drug Administration for the treatment of hepatitis B, immunomodulators (interferon [IFN]-α and pegylated-interferon [PEG-IFN]-α) and nucleos(t)ide analogs (lamivudine, telbivudine, adefovir, tenofovir [TDF], and entecavir [ETV]). Of these, ETV, TDF, and PEG-IFN-α are the most effective and are currently recommended for anti-HBV therapy. However, these therapies are less than optimal because of their low rate of viral DNA and surface antigen clearance; thus, there exists a significant unmet medical need for safe and efficacious new anti-HBV drugs. Covering diverse chemical structures and mechanisms of action, non-nucleos(t)ide compounds offer great promise in the search for new anti-HBV drugs. This review summarizes the currently approved anti-HBV drugs and highlights advances in the identification and characterization of novel small molecule HBV inhibitors. We discuss the sources, structures, anti-HBV effects, mechanisms of action, and potential toxicities of these novel inhibitors.


Assuntos
Antivirais/uso terapêutico , Desenho de Fármacos , Hepatite B Crônica/tratamento farmacológico , Animais , Antivirais/efeitos adversos , Antivirais/farmacologia , Carcinoma Hepatocelular/prevenção & controle , Carcinoma Hepatocelular/virologia , Aprovação de Drogas , Hepatite B Crônica/complicações , Hepatite B Crônica/epidemiologia , Humanos , Cirrose Hepática/prevenção & controle , Cirrose Hepática/virologia , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/virologia
7.
Yao Xue Xue Bao ; 48(9): 1376-82, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24358769

RESUMO

Hyaluronic acid (HA) as anticancer drug carrier has become the new hot point in the field of tumor-targeted drugs delivery system in recent years. Tumor therapeutic agents could be transmitted into cells because of hyaluronic acid innate ability to recognize specific cellular receptors that overexpressed on tumor cells surface. This review introduces the basic properties and physiology foundation of hyaluronic acid. Recent research developments based on different forms of HA tumor-targeted drugs delivery systems are reviewed in particular.


Assuntos
Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Ácido Hialurônico/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Humanos , Estrutura Molecular , Nanopartículas , Neoplasias/tratamento farmacológico
8.
Fitoterapia ; 84: 140-57, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23164603

RESUMO

There are 350,000 hepatitis B virus (HBV) carriers all over the world. Chronic HBV infection is at a high risk of developing liver cirrhosis and hepatocelluar carcinoma (HCC), and heavily threatened people's health. Two kinds of drugs approved by FDA for anti-HBV therapy are immunomodulators (interferon α, pegylated-interferon α) and nucleos(t)ide analogues (lamivudine, adefovir dipivoxil, entecavir, telbivudine, and tenofovir disoproxil fumarate). These drugs have been proved to be far from being satisfactory due to their low specificity, side effects, and high rate of drug resistance. There is an urgent need to discover and develop novel effective anti-HBV drugs. With vast resources, various structures, diverse biological activities and action mechanisms, as well as abundant clinical experiences, botanical agents become a promising source of finding new anti-HBV drugs. This review summarizes the recent research and development of anti-HBV agents derived from botanical origin on their sources and active components, inhibitory effects and possible toxicities, as well as action targets and mechanisms, and also addresses the advantages and the existing shortcomings in the development of botanical inhibitors. This information may not only broaden the knowledge of anti-HBV therapy, and offer possible alternative or substitutive drugs for CHB patients, but also provides considerable information for developing new safe and effective anti-HBV drugs.


Assuntos
Antivirais/química , Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Plantas/química , Humanos
9.
Yao Xue Xue Bao ; 45(9): 1177-82, 2010 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-21351576

RESUMO

Oxaliplatin-loaded nanostuctured lipid carriers (OP-NLC) were prepared by ultrasonic emulsification method. And its optimal prescription was selected by orthogonal design. The laser light scattering technique, zeta potential analyzer, TEM, DSC, XRD and HPLC were employed to study the physicochemical parameters of OP-NLC, which displayed in terms of particle size, zeta potential, crystalline, drug loading and encapsulation efficiency. The results showed that OP-NLC had an average diameter of (111 +/- 20) nm, zeta potential of (-27.4 +/- 13.1) mV, encapsulation efficiency of (77.4 +/- 2.5) % and drug content of (0.8 +/- 1.5) mg mL(-1). TEM, DSC and XRD indicated that OP-NLC was spherical and the drug was dispersed as nanoparticles by means of non-crystalline. The in vitro release test showed that the drug could be sustained-released from NLC in buffer solution (pH 4.5) after a burst release in initial phase.


Assuntos
Antineoplásicos/administração & dosagem , Lipídeos/química , Nanopartículas , Compostos Organoplatínicos/administração & dosagem , Antineoplásicos/química , Varredura Diferencial de Calorimetria , Cromatografia Líquida de Alta Pressão , Preparações de Ação Retardada , Portadores de Fármacos/química , Composição de Medicamentos , Microscopia Eletrônica de Transmissão , Compostos Organoplatínicos/química , Oxaliplatina , Tamanho da Partícula
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