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1.
Pharm Dev Technol ; 29(3): 248-257, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38416122

RESUMO

This study aimed to develop a tablet that shows a drug release profile similar to the tofacitinib sustained-release tablet (Xeljanz XR®; OROS™) using hot melt extrusion technology. Tofacitinib citrate was selected as the drug. HPMCAS, HPMCP, and Kollidon VA64 were used as thermoplastic polymers to prepare a hot-melt extrudate. The extrudate was obtained from a twin screw extruder and pelletizer. The granules were compressed using a single punch press machine and then coated. TGA, DSC, XRD, FT-IR, and SEM were performed on the hot melt extrudate to understand its physicochemical properties. Dissolution tests were performed using the paddle method (USP Apparatus II). The results showed that the crystallinity state of tofacitinib changed to amorphous after the hot melt extrusion process; however, no chemical change was observed. The drug release profile was similar to that of Xeljanz XR®, which has an initial lag time owing to its OROS™ formulation; a coating process was performed to obtain a similar drug release profile. The lag time was controlled by adjusting the thickness of the coating layer. Moreover, the extrudate size and compression force during tableting did not significantly affect drug release. In conclusion, the new tofacitinib sustained-release tablet prepared using hot melt extrusion showed a drug release behavior similar to that of Xeljanz XR®.


Assuntos
Tecnologia de Extrusão por Fusão a Quente , Temperatura Alta , Piperidinas , Pirimidinas , Tecnologia de Extrusão por Fusão a Quente/métodos , Preparações de Ação Retardada/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos/química , Liberação Controlada de Fármacos , Composição de Medicamentos/métodos
2.
Vaccine ; 41(17): 2816-2823, 2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-37024409

RESUMO

Worldwide, high pathogenic avian influenza viruses belonging to clades 2.3.4.4 and 2.3.2.1 have been circulating in both poultry and wild birds. Since 2018, Korea has built a national antigen bank to ensure preparedness in an emergency. In this study, we developed a bivalent vaccine candidate containing antigens derived from two reassortant KA435/2.3.2.1d and H35/2.3.4.4b strains for Korean national antigen bank. We evaluated its immunogenicity and protective efficacy in specific pathogen free chickens. The two vaccine strains, rgKA435-H9N2 PB2/2.3.2.1d and rgH35/2.3.4.4b, both of which were generated successfully by reverse genetics, were highly immunogenic (titres of haemagglutination inhibition: 8.3 and 8.4 log2, respectively) and showed good protective efficacy (100 and 147 50% protective dose, respectively) against lethal challenge with wild-type virus when delivered as a 1:1 mixture. Notably, the vaccine provided complete protection against viral shedding at a full dose (512 HAU) and a 1/10 dose (51.2 HAU), with no clinical signs, after challenge with H35/2.3.4.4b. The bivalent vaccine developed in this study may reduce the cost of vaccine production and could be used as a H5 subtype avian influenza vaccine candidate against two clades simultaneously.


Assuntos
Vírus da Influenza A Subtipo H9N2 , Vacinas contra Influenza , Influenza Aviária , Influenza Humana , Animais , Humanos , Galinhas , Vacinas Combinadas , Vacinas de Produtos Inativados , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética
4.
Vaccine ; 39(42): 6213-6220, 2021 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-34556363

RESUMO

Since June 2020, the Y280 lineage H9N2 virus, which is distinct from the previously endemic Y439 lineage, has been circulating in poultry in Korea. In this study, we developed two whole inactivated vaccines, rgHS314 and vac564, against the Y280 and Y439 lineages, respectively, and evaluated their immunogenicity and protective efficacy against homologous or heterologous viral challenge in mice. Serum neutralizing antibody titers in the rgHS314-vaccinated group were higher (68 ± 8.4 10log2) than in the vac564-vaccinated group (18 ± 8.4 10log2). In homologous challenge, rgHS314 conferred 100% protection, with no severe clinical signs, no body weight loss, and no viral replication in any tissues tested except the nasal turbinate. Viral replication in the lungs at 1, 3, 5, and 7 days post-infection (dpi) was significantly lower than in the sham group (p < 0.01). By contrast, all mice in the sham group were dead by 8 dpi with severe clinical signs and weight loss. Likewise, vac564 conferred 100% protection with no weight loss and with significantly lower viral replication in the lung than in the sham group at 3 dpi (p < 0.01). However, both vaccines showed partial protection in heterologous challenge. Our results suggest that both the rgHS314 and vac564 vaccines could be candidate vaccines for further evaluation in humans.


Assuntos
Vírus da Influenza A Subtipo H9N2 , Vacinas contra Influenza , Animais , Anticorpos Antivirais , Camundongos , República da Coreia , Vacinas de Produtos Inativados
5.
J Environ Radioact ; 213: 106139, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31983448

RESUMO

Interest is increasing in the radiological consequences of a release of aerosol and gaseous iodine, especially after the Fukushima accident and also because of new interpretations of the results of recent severe accident experiments. This work provides a brief review of the history of iodine chemistry in containment and suggests an approach to include gaseous iodine, namely in the forms of elemental iodine and organic iodide, in consequence analyses using the MACCS code. As dry deposition is an important characteristic to distinguish each chemical form of iodine when performing a consequence analysis, the mechanisms and mathematical formulas expressing dry deposition are also investigated. The proposed approach is demonstrated by performing consequence analyses with a unit release of 131I, with the resulting trends of concentration and dose for the different chemical forms of iodine presented and discussed. For the same amount of iodine release, there is a higher surface deposition of elemental iodine (I2) because it has a higher dry deposition velocity, while the air concentration of a representative organic iodide (CH3I) is higher due to its lower dry deposition velocity, which means a lower depletion of the air concentration. Despite elemental iodine having a lower air concentration, its higher dose coefficients for the inhalation pathway compensates for this when calculating doses. Further, inhaled doses increase when considering resuspension inhalation for extended durations of exposure. The approach proposed in this study is expected to be used flexibly to perform consequence analyses incorporating both aerosol and gaseous forms of iodine.


Assuntos
Iodo/análise , Monitoramento de Radiação , Poluentes Radioativos do Ar , Iodetos , Radioisótopos do Iodo
6.
Appl Radiat Isot ; 81: 190-5, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23602586

RESUMO

The UAE has started a nuclear energy program with the aim of having its first four units on-line between 2017 and 2020 and it is important that the country has an environmental radiation analysis capability to support this program. Khalifa University is therefore implementing a research laboratory to support both experimental analysis and radionuclide transport modeling in the aquatic and terrestrial environment. This paper outlines the development of this capability as well as the work in progress and planned for the future.


Assuntos
Programas Governamentais/organização & administração , Física Nuclear/organização & administração , Monitoramento de Radiação/instrumentação , Monitoramento de Radiação/métodos , Pesquisa/organização & administração , Emirados Árabes Unidos
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