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1.
Process Biochem ; 118: 154-170, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35437418

RESUMO

Cases of deaths due to COVID-19 (COrona VIrus Disease-19) infection are increasing gradually worldwide. Immense research is ongoing to control this pandemic condition. Continual research outcomes are indicating that therapeutic and prophylactic agents are the possible hope to prevent the pandemic from spreading and to combat this increasing death count. Experience gained from previous coronavirus infections (eg., SARS (Severe Acute Respiratory Syndrome), MERS (Middle Ease Respiratory Syndrome), accumulated clinical knowledge during this pandemic, and research helped to identify a few therapeutic agents for emergency treatment of COVID-19. Thereby, monoclonal antibodies, antivirals, broad-spectrum antimicrobials, immunomodulators, and supplements are being suggested for treatment depending on the stage of the disease. These recommended treatments are authorized under medical supervision in emergency conditions only. Urgent need to control the pandemic condition had resulted in various approaches of repurposing the existing drugs, However, poorly designed clinical trials and associated outcomes do not provide enough evidence to fully approve treatments against COVID-19. So far, World Health Organization (WHO) authorized three vaccines as prophylactic against SARS-CoV-2. Here, we discussed about various therapeutic agents, their clinical trials, and limitations of trials for the management of COVID-19. Further, we have also spotlighted different vaccines in research in combating COVID-19.

2.
Semin Cancer Biol ; 69: 365-375, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-31442571

RESUMO

The application of nanomedicines in tumor targeting and attaining meaningful therapeutic benefits for the treatment of cancers has been going on for almost two decades. Beyond the lipidic and polymeric nanomedicines-based passive and active targeting, the quest for inventing the new generation of carriers has no end. This has lead to the evolution of some of the unique carrier systems with supramolecular assembly structures. Mesoporous nanoparticulate systems (MSNPs) are the recently explored substances with favorable potential for drug delivery and drug targeting applications especially in cancer chemotherapeutics. Notwithstanding their physical properties that makes them a suitable carrier for cancer treatment, but their outstanding ability towards chemical functionalization helps in delivering the imaging agents for diagnostic applications. MSNPs can improve the dissolution rate and systemic availability of the poorly water soluble drugs due to their mesoporous structures. Besides, guest molecules including targeting ligands, biomimetic agents, fluorescent dyes, and biocompatible polymers can be efficiently encapsulated in their tunable porous structure for targeting purpose. Some special features of the MSNPs which make them one of the highly effective nanocarrier systems include their ability to encapsulate non-crystalline drugs in their mesopores, high dispersion ability as a function of large surface area and wetting properties. For anticancer drug delivery, MSNPs are worthful to provide excellent drug loading capacity and endocytotic behavior. Moreover, the external surface of MSNPs can be precisely modified for tumor-recognition and developing sensitivity of the antitumor agents towards the cancer cells. Owing to the innumerable applications of MSNPs till now in cancer treatment, the present article particularly focuses to provide an overview account with complete details on the topic to make the readers abreast with details on physiochemical and material properties of MSNPs, their applications and current innovations for the purpose.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Nanomedicina , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Dióxido de Silício/química , Animais , Humanos , Nanopartículas/química , Neoplasias/patologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-33212399

RESUMO

A systematic approach to develop a UPLC-MS/MS method was applied for quantifying of risperidone (RISP), its active metabolite, 9-hydroxy risperidone (9-OH-RISP) and internal standard (propranolol) in rat plasma. Liquid-liquid extraction was performed using methyl tert-butyl ether for quantification of drug and its active metabolite by MS detection in the positive ion mode. Acquity UPLC system with BEH C18 (2.1 mm × 100 mm, particle size 1.7 µm) column was used along with acetonitrile (0.1% formic acid)-2 mM (milli mole) ammonium acetate in isocratic condition was used as the mobile phase. Detection was performed by multiple reactions monitoring with precursor-to-product ion transitions with m/z 411.2 â†’ 191.0 for RISP, m/z 427.2 â†’ 207.0 for 9-OH-RISP and m/z 260.1 â†’ 116.0 for IS. The method was validated as per the FDA guidance on bioanalytical method validation. Linearity (r2 = 0.999) was observed in the drug concentration ranging between 0.1 and 50 ng mL-1, while all other parameters were found to be within the acceptable ranges. Method robustness was optimized by Box-Behnken design to monitor the influential variables to achieve maximal recovery of the analytes in the rat plasma. Pharmacokinetic evaluation of the analytes from long-acting microparticles in rat plasma showed two peaks indicating an initial burst effect within 24 h of administration followed by controlled drug release pattern upto 45 days, while marketed formulation (Risperdal Consta®) showed no plasma concentration during the lag-time of 21 days followed by maximal drug absorption between 28 and 40 days.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Risperidona/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Preparações de Ação Retardada , Estabilidade de Medicamentos , Limite de Detecção , Modelos Lineares , Extração Líquido-Líquido , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Risperidona/química , Risperidona/farmacocinética
4.
J Chromatogr Sci ; 49(2): 136-41, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21223639

RESUMO

Docetaxel has significant single agent activity in prostate cancer and ketoconazole also has activity as a second line hormonal agent. In vitro, ketoconazole is synergistic with some chemotherapy agents by enhancing the intracellular retention of the cytotoxic agent. A potential drug-drug interaction exists though between docetaxel and ketoconazole because both agents are metabolized hepatically by the cytochrome P-450 system. Hence, a nanoparticulate system was formulated by loading both drugs for tumor targeting. Assay and in vitro release of the formulation were conducted by developing simple, precise, accurate, and validated analytical method for simultaneous determination docetaxel and ketoconazole using reversed-phase high-performance liquid chromatography (RP-HPLC). The RP-HPLC method was developed using Waters Symmetry C(18) column (25 cm × 4.5 mm, 5 µm) with a mobile phase consisting of acetonitrile and 0.2% triethylamine pH adjusted to 6.4 (48:52, v/v) at flow rate of 1 mL/min. Intra-day and inter-day variations were less than 2% over the linearity range, 0.5-20 µg/mL. The proposed two methods were successfully applied for the determination of docetaxel and ketoconazole in solid lipid nanoparticles.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cetoconazol/análise , Lipídeos/química , Nanopartículas/química , Taxoides/análise , Cromatografia de Fase Reversa/métodos , Docetaxel , Sistemas de Liberação de Medicamentos , Estabilidade de Medicamentos , Cetoconazol/química , Cetoconazol/farmacocinética , Análise dos Mínimos Quadrados , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Taxoides/química , Taxoides/farmacocinética
5.
Recent Pat Drug Deliv Formul ; 3(2): 153-61, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19519575

RESUMO

In the recent years, there has been a growing interest in the development of nanoparticles based targeting agents for the tumor diagnostics and therapeutics. This is because of their potential to detect the tumor and treat the diseased tissue at the cellular and molecular level. In this respect nanoscale magnetic materials have shown a very promising therapeutic concept and offer a new perspective for the diagnostic and target drug delivery approach. The magnetic nanocarriers have the ability to accumulate at any desired pharmacological site just by the guidance of external magnetic field. But, the interactions of these magnetic nanocarriers with the biological environment are rare and depend largely upon their surface chemistry and size. To increase the interactions and achieve the desired pharmaceutically acceptable delivery system, the surface of magnetic nanocarriers is modified in various ways by coating with organic polymers and inorganic metals or oxides. On the basis of surface characteristics, a number of effective magnetically driven therapies have been proposed by many researchers and protected through patents time to time.


Assuntos
Engenharia Biomédica/tendências , Sistemas de Liberação de Medicamentos/métodos , Magnetismo/métodos , Nanopartículas/uso terapêutico , Animais , Compostos Férricos/química , Compostos Férricos/uso terapêutico , Humanos , Hipertermia Induzida/métodos , Separação Imunomagnética/métodos , Nanopartículas/química , Nanotecnologia , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Patentes como Assunto , Propriedades de Superfície
6.
Eur J Pharm Biopharm ; 69(2): 426-35, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18295464

RESUMO

Mucoadhesive nanoparticles (NPs) could be an exciting prospect for trans-nasal insulin delivery as they have higher surface area to cover highly vascularised nasal absorptive area providing a greater concentration gradient; hence the present study makes an attempt in this regard. Starch NPs were prepared by different crosslinkers using various methodologies and were loaded with insulin. Emulsion crosslinked particles were smaller in size compared to gel method (351 vs 997 nm), and size is further reduced when epichlorohydrin is used as crosslinking agent compared to POCl3 (194 vs 810 nm). NPs of epichlorohydrin emulsion were further optimized with variable crosslinking to evaluate the effect of degree of crosslinking on in vivo performance. In vitro, a size dependent first order diffusion controlled insulin release with an initial burst effect was found, which is higher with NPs of small size and least crosslinking. Formulation of EE-NPs with Na glycocholate showed a superior hypoglycemic action compared to other NPs formulations containing the former and lysophosphatidylcholine as permeation enhancers. The hypoglycemic effects were more pronounced with medium crosslinked NPs (EE-L2-NPs), which showed a nadir of 70% reduction of plasma glucose and significant effects until 6h. The peak plasma insulin level (Cmax) of medium crosslinked EE-L2-NPs (258 muIU/ml at 1h) vindicates the pharmacodynamic effect, which was found to be superior compared to all other formulations. The release rate and higher associated surface area might work in tandem, and could be greatly amplified when combined with permeation enhancers to make starch NPs an efficient trans-nasal mucoadhesive carrier of insulin.


Assuntos
Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Nanopartículas , Amido , Adesivos , Administração Intranasal , Animais , Área Sob a Curva , Glicemia/metabolismo , Reagentes de Ligações Cruzadas , Diabetes Mellitus Experimental/tratamento farmacológico , Epicloroidrina , Excipientes , Ácido Glicocólico , Insulina/sangue , Insulina/uso terapêutico , Lisofosfatidilcolinas , Masculino , Tamanho da Partícula , Ratos , Ratos Wistar , Solventes
7.
Artigo em Inglês | MEDLINE | ID: mdl-17921613

RESUMO

BACKGROUND: Topical retinoids normalize desquamation, reduce comedogenesis and may enhance the penetration of other topicals providing more effective treatment of acne. AIM: We evaluated the effect of adapalene on skin penetration of clindamycin phosphate when it is applied concomitantly or after various time durations following adapalene application. METHODS: The in vitro studies were carried out using excised rat skin, whereas the in vivo studies were conducted on healthy human volunteers. Radioactive clindamycin phosphate (1%) gel was applied to rat skin sections and to the hands of human volunteers concomitantly and after the pretreatment of the skin for 3, 5 and 10 min with 10 mg of adapalene (0.1%) gel. Quantification of clindamycin phosphate was performed by liquid scintillation. RESULTS: In vitro skin penetration and distribution of clindamycin phosphate was affected by the pretreatment time. Significantly higher skin concentration of clindamycin phosphate (15.5%) with largest proportion in viable skin layer (9.4% of applied dose) was found when clindamycin phosphate gel was applied after the pretreatment of the skin with adapalene gel for 5 min. Further increase in pretreatment time has no additive influence on the penetration of clindamycin phosphate. In vivo results were in corroboration with the in vitro results and demonstrate significantly higher concentration of clindamycin phosphate (19%) in the skin following pretreatment with adapalene gel for 5 min. Adapalene acts as a penetration enhancer and increases the penetration of topical clindamycin phosphate. CONCLUSION: Application of clindamycin phosphate gel after the pretreatment of skin with adapalene gel for 5 min may contribute significantly to the increased efficacy of therapy.


Assuntos
Antibacterianos/farmacocinética , Clindamicina/análogos & derivados , Ceratolíticos/farmacologia , Naftalenos/farmacologia , Absorção Cutânea/efeitos dos fármacos , Adapaleno , Administração Tópica , Adulto , Animais , Clindamicina/farmacocinética , Quimioterapia Combinada , Humanos , Técnicas In Vitro , Masculino , Cintilografia , Ratos , Pele/diagnóstico por imagem , Pertecnetato Tc 99m de Sódio
8.
J Drug Target ; 15(6): 417-27, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17613660

RESUMO

Considering limitations of conventional insulin therapies, the present study characterizes usefulness of novel mucoadhesive multivesicular liposomes as a mucoadhesive sustained release carrier of insulin via nasal and ocular routes, thus attempts to develop non-invasive carrier system for the controlled release of bioactives. Multivesicular liposomes (MVLs) of 26-34 microm were prepared with a high protein loading (58-62%) and were coated with chitosan and carbopol. These mucoadhesive carriers were characterized by zeta potential studies, in vitro mucoadhesion test and insulin protective ability against nasal aminopeptidase. In vitro, mucoadhesive carriers released insulin for a period of 7-9 days compared to 24 h of conventional liposomes. After intranasal administration to STZ induced diabetic rats, the mucoadhesive MVLs (chitosan coated MVLs) effectively reduced plasma glucose level up to 2 days (35% reduction), compared to non-coated MVLs (32% at 12 h) and conventional liposomes (34% at 8 h). Although the differences are statistically insignificant, chitosan coated formulation has shown a better hypoglycemic profile as the effects were prolonged compared to carbopol coated formulation. When compared to ocular route, chitosan formulation after nasal administration has shown better therapeutic profile as the hypoglycemic effects were prolonged until 72 h. The effectiveness of this chitosan coated MVLs was further demonstrated by the significant quantities of ELISA detectable insulin levels after nasal (334.6 microIu/ml) and ocular (186.3 microIu/ml) administration. These results demonstrate that mucoadhesive carrier is a viable option for a sustained release transmucosal insulin carrier, and open an avenue to develop a non-invasive carrier platform for the controlled release of bioactives.


Assuntos
Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Mucosa Intestinal/química , Lipossomos/química , Mucosa Nasal/química , Resinas Acrílicas , Adesivos , Administração Intranasal , Administração Tópica , Animais , Quitosana/química , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Hipoglicemiantes/sangue , Insulina/sangue , Masculino , Membranas Mitocondriais/química , Soluções Oftálmicas , Polivinil/química , Ratos , Ratos Wistar
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