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1.
J Vet Pharmacol Ther ; 47(1): 36-47, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37593974

RESUMO

Toltrazuril (TZR) is currently the only registered chemotherapeutic drug in the European Union for the treatment of Cystoisospora suis. This study investigated the comparative pharmacokinetics and tissue concentration-time profiles of TZR and its active metabolite, toltrazuril sulfone (TZR-SO2 ), after oral (per os, p.o.) and intramuscular (i.m.) administration to suckling piglets. Following a single administration of TZR orally at 50 mg/piglet or intramuscularly at 45 mg/piglet, higher concentrations of TZR and TZR-SO2 were observed in all three investigated tissues after p.o. administration. The mean TZR concentration in serum peaked at 14 µg/mL (34.03 h) and 5.36 µg/mL (120 h), while TZR-SO2 peaked at 14.12 µg/mL (246 h) and 9.92 µg/mL (330 h) after p.o. and i.m. administration, respectively. TZR was undetectable in the liver after p.o. administration (18 days) and in the jejunum (24 days) after i.m. injection, while TZR-SO2 was still detectable in all three tissues after 36 days regardless of administration routes. This study showed that p.o. formulation exhibited faster absorption and higher serum/tissue TZR/TZR-SO2 concentrations than i.m. formulation. Both formulations generated sufficient therapeutic concentrations in the serum and jejunum, and sustained enough time to protect against Cystoisospora suis infection in the piglets.


Assuntos
Coccidiostáticos , Animais , Suínos , Administração Oral , Triazinas , Sulfonas , Injeções Intramusculares/veterinária
2.
Sensors (Basel) ; 20(20)2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33050320

RESUMO

A novel interactive system for calligraphy called mind calligraphy that reflects the writer's emotions in real time by affective computing and visualization techniques is proposed. Differently from traditional calligraphy, which emphasizes artistic expression, the system is designed to visualize the writer's mental-state changes during writing using audio-visual tools. The writer's mental state is measured with a brain wave machine to yield attention and meditation signals, which are classified next into the four types of emotion, namely, focusing, relaxation, calmness, and anxiety. These emotion types then are represented both by animations and color palettes for by-standing observers to appreciate. Based on conclusions drawn from data collected from on-site observations, surveys via Likert-scale questionnaires, and semi-structured interviews, the proposed system was improved gradually. The participating writers' cognitive, emotional, and behavioral engagements in the system were recorded and analyzed to obtain the following findings: (1) the interactions with the system raise the writer's interest in calligraphy; (2) the proposed system reveals the writer's emotions during the writing process in real time via animations of mixtures of fish swimming and sounds of raindrops, insects, and thunder; (3) the dynamic visualization of the writer's emotion through animations and color-palette displays makes the writer understand better the connection of calligraphy and personal emotions; (4) the real-time audio-visual feedback increases the writer's willingness to continue in calligraphy; and (5) the engagement of the writer in the system with interactions of diversified forms provides the writer with a new experience of calligraphy.


Assuntos
Distúrbios Distônicos , Emoções , Humanos , Interface Usuário-Computador , Redação
3.
J Org Chem ; 84(11): 7480-7487, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31062593

RESUMO

A general and straightforward protocol for di-/perfluoroalkylation of ortho-hydroxycinnamic esters via a photoredox-catalyzed cascade was developed to access a variety of 3-fluoroalkylated coumarins. This method was characterized by all-in-one synthetic design, simplified operation, mild reaction conditions, and broad substrate scope. Moreover, a sequential one-pot procedure starting from commercially available salicylaldehyde was also successfully realized to synthesize 3-fluoroalkylated coumarins.

4.
J Org Chem ; 83(19): 12284-12290, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30183297

RESUMO

A facile and enantioselective access to a functionalized octahydroacridine scaffold was developed via an organocatalytic domino sequence between cyclohexenone and 2- N-substituted benzaldehyde. High levels of yields (up to 99%) and enantioselectivities (up to 99:1 er) were readily achieved in this developed organocatalytic transformation, which holds promising applications in the construction of complex multicyclic systems for further pharmacological studies.

5.
J Org Chem ; 82(7): 3895-3900, 2017 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-28281753

RESUMO

Reductive dimerization of isatin and its derivatives can be regarded as a step-economical pathway to construct 3,3'-disubstituted bisoxindoles, which was unfortunately accompanied by severe direct reduction as well as low efficiency. A visible-light driven, photoredox-catalytic protocol was developed to readily furnish 3,3'-dihydroxy- (dl-, > 20:1 dr) and 3,3'-diamino-bisoxindoles (meso-, 3.5:1 to 5:1 dr) in moderate to good yields, successfully circumventing the common problem. Two vicinal quaternary carbon centers were effectively assembled under the irradiation of visible light.

6.
Molecules ; 22(12)2017 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-29207567

RESUMO

A novel series of 11,12-cyclic carbonate azithromycin-3-O-descladinosyl-3-O-carbamoyl glycosyl derivatives were designed, synthesized, and evaluated for their antibacterial activities in vitro. Most of these compounds had significant antibacterial activity against seven kinds of susceptible strains. In particular, compound G1 exhibited the most potent activity against methicillin-resistant Streptococcus pneumoniae 943 (MIC: 1 µg/mL), Staphylococcus pneumoniae 746 (MIC: 2 µg/mL), Streptococcus pyogenes 447 (MIC: 8 µg/mL), and Escherichia coli 236 (MIC: 32 µg/mL), which were two-, four-, four-, four-, and eight-fold stronger activity than azithromycin, respectively. Additionally, compound G2 exhibited improved activity against methicillin-resistant Staphylococcus aureus MRSA-1 (MIC: 8 µg/mL), Streptococcus pneumoniae 943 (MIC: 2 µg/mL), Staphylococcus pneumoniae 746 (MIC: 2 µg/mL), and Escherichia coli 236 (MIC: 32 µg/mL), which were two-, two-, four-, and eight-fold better activity than azithromycin, respectively. As for methicillin-resistant Staphylococcus aureus MRSA-1, compound G6 presented the most excellent activity (MIC: 4 µg/mL), showing four-fold higher activity than azithromycin (MIC: 16 µg/mL) and erythromycin (MIC: 16 µg/mL). However, compared with other compounds, compounds G7 and G8 with the disaccharide side chain were observed the lower activity against seven strains.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Azitromicina/química , Azitromicina/farmacologia , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pyogenes/efeitos dos fármacos
7.
J Org Chem ; 81(17): 8001-8, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27463393

RESUMO

Highly diastereo- and enantioselective conjugate additions of azlactones to enolizable cyclic and linear enones were conducted by employing proline aryl sulfonamide as the organocatalyst in trifluorotoluene. The conjugate adducts bearing contiguous quaternary and tertiary stereocenters were obtained in moderate to good yields with excellent diastereoselectivities and moderate to good enantioselectivities. This developed protocol filled in the substrate gap for the organocatalytic conjugate addition of azlactone to enones.

8.
Ergonomics ; 58(8): 1253-65, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25680001

RESUMO

This study examined usability principles and interface designs in order to understand the relationship between the intentions of mobile e-book interface designs and users' perceptions. First, this study summarised 4 usability principles and 16 interface attributes, in order to conduct usability testing and questionnaire survey by referring to Nielsen (1993), Norman (2002), and Yeh (2010), who proposed the usability principles. Second, this study used the interviews to explore the perceptions and behaviours of user operations through senior users of multi-touch prototype devices. The results of this study are as follows: (1) users' behaviour of operating an interactive interface is related to user prior experience; (2) users' rating of the visibility principle is related to users' subjective perception but not related to user prior experience; however, users' ratings of the ease, efficiency, and enjoyment principles are related to user prior experience; (3) the interview survey reveals that the key attributes affecting users' behaviour of operating an interface include aesthetics, achievement, and friendliness. PRACTITIONER SUMMARY: This study conducts experiments to explore the effects of users' prior multi-touch experience on users' behaviour of operating a mobile e-book interface and users' rating of usability principles. Both qualitative and quantitative data analyses were performed. By applying protocol analysis, key attributes affecting users' behaviour of operation were determined.


Assuntos
Livros , Aplicativos Móveis , Interface Usuário-Computador , Adulto , Comportamento do Consumidor , Feminino , Humanos , Masculino , Percepção , Inquéritos e Questionários , Taiwan
9.
Artigo em Inglês | MEDLINE | ID: mdl-36612448

RESUMO

An interactive digital gaming system with simple tangible interfaces is proposed for use by slightly disabled elderly people to promote their health and enjoyment of playful aging. The system simulates a rice threshing machine with nostalgic and entertaining functions expected to bring better life quality to older adults. Initially, pieces of literature were reviewed to derive relevant design principles. A prototype system was constructed accordingly and refined according to the invited older users' comments. The refined system was performed subsequently by slightly disabled elderly people, followed by a questionnaire survey conducted to collect their opinions. The opinion data were analyzed statistically by SPSS and AMOS to be reliable and valid. In addition, interviews were conducted with the users and experts were invited to collect comments on the system's usability, which were then evaluated to reveal several findings about the system's effectiveness: (1) digital products related to life experiences are more acceptable to slightly disabled elderly people, promoting their willingness to play games to achieve active aging; (2) simple system interfaces requiring no complicated limb functions are appropriate for the slightly disabled elderly people; and (3) digital gaming has the effects of training slightly disabled elderly peoples' cognitive and motor abilities as well as strengthening their body and mind.


Assuntos
Pessoas com Deficiência , Jogos de Vídeo , Humanos , Idoso , Tecnologia Digital , Envelhecimento , Extremidades , Jogos de Vídeo/psicologia
10.
Healthcare (Basel) ; 8(2)2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32575389

RESUMO

To help older adults achieve active aging, an interactive device with tangible interfaces is proposed, which combines human-machine interaction techniques and older adults' life experiences to provide three functions: nostalgia, leisure, and entertainment. Firstly, by a review of related theories and studies, principles for designing a desirable interactive device were established. Accordingly, a prototype device with an interactive game was constructed, which was then tested in a field experiment and improved according to the users' opinions collected by interviews. Subsequently, in a second experiment the users' and some experts' feedback about the system's usability and user interaction satisfaction was collected and analyzed, and found to be reliable and valid for further evaluations of the effectiveness of the proposed system, resulting in the following findings about the older adults who have played the game: the participants become more willing to use technological devices; involving them in the game creates positive aging effects; participants become more receptive to technology products; the participating older adults' cognitive abilities are trained and their body exercises increased, creating sensory stimulation and health promotion effects; and considering users with cognitive impairments who have stress and difficulty operating the device, the system needs to be improved in the future.

11.
Enzyme Microb Technol ; 135: 109498, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32146931

RESUMO

Whole-cell biocatalysts could be used in wide-ranging applications. In this study, a new kind of whole-cell biocatalyst was successfully constructed by genetically immobilizing soybean seed coat peroxidase (SBP) on the cell surface of Yarrowia lipolytica Po1h, using a new integrative surface display expression vector (pMIZY05). The coding sequence of SBP was optimized and chemically synthesized, then inserted into pMIZY05 to generate expression plasmid pMIZY05-oEp. A DNA fragment corresponding to SBP and selection marker expression cassettes, without bacterial sequences, was released from pMIZY05-oEp by enzyme digestion and used to transform host yeast cells. A transformant (CM11) with a high recombinant SBP activity of 1571.9 U/mL was obtained, and recombinant SBP was proved to be successfully anchored on cell surface by testing the activities of different cellular fractions. After optimization of culture conditions, the recombinant SBP activity of CM11 was increased to 4187.8 U/mL. Afterwards, biochemical properties of the recombinant SBP were determined: optimum catalytic conditions were 37.5℃ at pH 3.5, and recombinant SBP exhibited high stability during thermal or acidic treatment. Recombinant activity of cell-displayed SBP was re-examined at optimum temperature and pH, which promoted an increase up to 4432.5 U/mL. To our knowledge, this represents the highest activity ever reported for heterologous expression of SBP. This study also provides a useful strategy for heterologous expression of proteins which could be toxic to intracellular content of host cells.


Assuntos
Peroxidases/genética , Proteínas de Soja/genética , Yarrowia/genética , Biocatálise , Clonagem Molecular , Estabilidade Enzimática , Expressão Gênica , Peroxidases/química , Peroxidases/metabolismo , Plasmídeos/genética , Plasmídeos/metabolismo , Proteínas de Soja/química , Proteínas de Soja/metabolismo , Yarrowia/metabolismo
12.
Chem Asian J ; 13(3): 271-274, 2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-29316376

RESUMO

A facile visible-light photocatalytic conjugate addition to prepare 1,4-dicarbonyl compounds has been developed by employing readily available aroyl chlorides as aryl radical sources. This operationally simple method shows a broad scope with regard to both aroyl chlorides and Michael acceptors. As a result, a variety of 1,4-diketones were efficiently synthesized in moderate to good yields.

13.
Org Lett ; 20(23): 7535-7538, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30411899

RESUMO

An l-pyroglutamic acid-derived bifunctional organocatalyst was designed and applied in an organocatalytic asymmetric direct aldol reaction between isatins and cyclohexanone, in which an erosion of enantiomeric excess of aldol adduct was unexpectedly observed. Through closely monitoring the reaction and performing extensive control experiments, it was determined that the erosion of ee was attributed to a rare stereospecific retro-aldol process. Moreover, effective manipulation of the retro-aldol process by tuning the use of starting materials was ultimately accomplished, leading to evidently upgraded enantioselectivity and functional group tolerance. This study demonstrates the impact of the hidden reaction pathway on the enantioselectivity in asymmetric transformation.

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