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1.
Int J Pharm ; 491(1-2): 8-16, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26051543

RESUMO

The use of solid oral dosage forms is typically favored with regard to stability and ease of administration. The aim of this study was to investigate whether cyclodextrins (CD) or ion exchange resins (IER) could be used to taste-mask cetirizine HCl when formulated in a freeze-dried oral formulation. The oral lyophilisates were produced using the Zydis(®) technology that offer the opportunity to produce the dosage form directly in the aluminum laminate blister packs. This study confirmed that a pre-formed resinate of cetirizine HCl and various cyclodextrins can be successfully incorporated into the Zydis(®) oral lyophilisate. A chemically stable product with acceptable release profile was obtained in the case of cyclodextrin. This study has also demonstrated that the Insent(®) taste sensing system is a useful technique for predicting the taste-masking potential of Zydis(®) formulations. The electronic taste sensing system (e-tongue) data can be used to provide guidance on the selection of taste-masked formulations. Principal component analysis (PCA) of sensor data by plotting the PCA scores revealed the effects of used taste-masking techniques on the e-tongue sensors, indicating the successful taste improvement. The PCA plot of the taste sensor data revealed larger distances between the non-taste-masked sample and the CD- and IER-loaded samples, and the shift toward the drug-free formulations and excipient signals indicates a modification of the product taste. The human taste trial confirms the acceptability of the selected promising formulations. The taste evaluation results showed that an effectively taste-masked formulation has been achieved using ß-cyclodextrin and cherry/sucralose flavor system with over 80% of volunteers finding the tablet to be acceptable.


Assuntos
Cetirizina/administração & dosagem , Cetirizina/química , Administração Oral , Adolescente , Adulto , Química Farmacêutica/métodos , Ciclodextrinas/química , Excipientes/química , Feminino , Liofilização/métodos , Humanos , Resinas de Troca Iônica/química , Masculino , Pessoa de Meia-Idade , Prunus avium/química , Método Simples-Cego , Solubilidade , Sacarose/análogos & derivados , Sacarose/química , Comprimidos/química , Paladar/fisiologia , Língua/fisiologia , Adulto Jovem , beta-Ciclodextrinas/química
2.
Environ Sci Technol ; 45(16): 6777-83, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21770387

RESUMO

Hypoxia is a well-described phenomenon in the offshore waters of the Baltic Sea with both the spatial extent and intensity of hypoxia known to have increased due to anthropogenic eutrophication, however, an unknown amount of hypoxia is present in the coastal zone. Here we report on the widespread unprecedented occurrence of hypoxia across the coastal zone of the Baltic Sea. We have identified 115 sites that have experienced hypoxia during the period 1955-2009 increasing the global total to ca. 500 sites, with the Baltic Sea coastal zone containing over 20% of all known sites worldwide. Most sites experienced episodic hypoxia, which is a precursor to development of seasonal hypoxia. The Baltic Sea coastal zone displays an alarming trend with hypoxia steadily increasing with time since the 1950s effecting nutrient biogeochemical processes, ecosystem services, and coastal habitat.


Assuntos
Monitoramento Ambiental , Oxigênio/análise , Água do Mar/química , Anaerobiose , Geografia , Oceanos e Mares , Fatores de Tempo
3.
Chem Commun (Camb) ; 47(1): 253-5, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-20601994

RESUMO

N-alkylation of a novel pyridine sensor results in pyridinium salts whose conformations are stabilised by pyridinium cation-π interactions resulting in a fluorescent response that can be used to sense the presence of alkylating agents in solution at low concentration.


Assuntos
Fluorescência , Corantes Fluorescentes/química , Hidrocarbonetos Halogenados/análise , Piridinas/química , Alquilação , Cátions/química , Cristalografia por Raios X , Corantes Fluorescentes/síntese química , Modelos Moleculares , Estrutura Molecular , Piridinas/síntese química , Soluções , Espectrometria de Fluorescência
4.
Mar Pollut Bull ; 60(6): 919-24, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20381096

RESUMO

We report the development of a methodology for assessing confidence in ecological status classifications. The method presented here can be considered as a secondary assessment, supporting the primary assessment of eutrophication or ecological status. The confidence assessment is based on scoring the quality of the indicators on which the primary assessment is made. This represents a first step towards linking status classification with information regarding their accuracy and precision. Applied to an existing data set used for assessment of eutrophication status of the Baltic Sea (including the Kattegat and Danish Straits) we demonstrate that confidence in the assessment is Good or High in 149 out of 189 areas assessed (79%). Contrary to our expectations, assessments of the open parts of the Baltic Sea have a higher confidence than assessments of coastal waters. We also find that in open waters of the Baltic Sea, some biological indicators have a higher confidence than indicators representing physical-chemical conditions. In coastal waters, phytoplankton, submerged aquatic vegetation and indicators of physical-chemical conditions have a higher confidence than indicators of the quality of benthic invertebrate communities. Our analyses also show that the perceived weaknesses of eutrophication assessments are due more to Low confidence in reference conditions and acceptable deviations, rather than in the monitoring data.


Assuntos
Classificação/métodos , Monitoramento Ambiental/métodos , Eutrofização , Projetos de Pesquisa , Interpretação Estatística de Dados , Monitoramento Ambiental/estatística & dados numéricos , Oceanos e Mares
5.
Dalton Trans ; (46): 10169-71, 2009 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-19921048

RESUMO

A chiral pseudo-C(3)-symmetric titanium triflate that employs the point chirality of a single stereogenic centre to control the propeller chirality of its aryl rings has been used to catalyse an asymmetric sulfoxidation reaction.


Assuntos
Mesilatos/química , Sulfóxidos/química , Titânio/química , Catálise , Conformação Molecular , Estereoisomerismo
6.
Chem Commun (Camb) ; (9): 1082-4, 2008 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-18292897

RESUMO

NOEsy and fluorescence spectroscopy reveal that conversion of conformationally flexible (phenylalkyl)pyridines into their corresponding N-methyl-pyridinium iodides results in intramolecular pi-stacking.


Assuntos
Iodetos/química , Piridinas/química , Compostos de Piridínio/química , Cátions/química , Espectroscopia de Ressonância Magnética/métodos , Conformação Molecular , Espectrometria de Fluorescência/métodos
7.
Org Lett ; 9(2): 223-6, 2007 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-17217270

RESUMO

An enantiopure amine tris(phenolate) ligand containing a single stereogenic center has been used to control the propeller-like chirality of a derived pseudo-C3-symmetric titanium isopropoxide complex with excellent levels of diastereocontrol. [structure: see text].


Assuntos
Compostos Organometálicos/química , Titânio/química , Cristalografia por Raios X , Ligantes , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Estrutura Molecular , Sensibilidade e Especificidade , Estereoisomerismo
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