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1.
Health Commun ; : 1-11, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38567546

RESUMO

The health literacy of immigrants has been often viewed in a deficit model. By using structuration theory as a theoretical lens, this study aimed to uncover the health literacy development of Korean immigrants in the U.S. as an agentic behavior during the COVID-19 pandemic. A total of 20 semi-structured interviews were conducted with Korean immigrants in the U.S. Findings reveal how the participants' experience was shaped by structural forces such as conflicting but co-existing public health systems between the U.S. and Korea, information overload, and the uncertainty surrounding the pandemic. Participants also employed strategies such as constantly comparing the public health guidelines from the two countries, critically appraising the information, deliberately choosing which guideline to follow, combating misinformation, and regulating media consumption. These strategies enabled them to develop health literacy by leveraging their immigrant status as an advantage. Theoretical, practical, and policy implications are discussed.

2.
Healthcare (Basel) ; 12(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38470635

RESUMO

BACKGROUND: This study aimed to determine whether self-regulation acts as a mediating factor in the relationship between obesity-related stress and weight control behavior, targeting Korean female college students. Obesity-related stress and weight control behaviors are important factors affecting an individual's health and well-being, and self-control, a psychological trait, can play a pivotal role in regulating how individuals respond to stress and engage in weight management behaviors. METHODS: This study employed a descriptive correlational design. A total of 109 female college students with overweight and obesity participated in the study. We used a self-report questionnaire to measure obesity-related stress, self-control, and degree of weight control behavior. Data were analyzed using descriptive statistics, Pearson's correlation coefficient analysis, and bootstrapping using Hayes' PROCESS macro for mediation. RESULTS: Significant relationships between obesity-related stress and weight control behavior (r = 0.25, p < 0.001), obesity-related stress and self-control (r = -0.36, p < 0.001), and weight control behavior and self-control (r = 0.26, p < 0.001) were observed. Self-control showed an indirect mediating effect on the relationship between obesity-related stress and weight control behavior (Β = 0.37, p = 0.001). CONCLUSIONS: Through the research results, it was confirmed that self-control is a factor that has a mediating effect in the relationship between obesity-related stress and weight control behavior among female college students with overweight and obesity. These results underscore the importance of addressing self-control strategies in interventions aimed at promoting healthy weight management among female college students with overweight or obesity.

3.
Sensors (Basel) ; 24(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38257477

RESUMO

In this paper, we propose a deployable broadband mesh reflector antenna for use in signals intelligence (SIGINT) satellite systems, considering performance degradation due to shape deformation. To maximize gain by increasing the diameter of the reflector while reducing the weight of the antenna, the reflector of the antenna is designed using lightweight silver-coated Teflon mesh. The mesh reflectors are typically expanded by tension to maintain their parabolic structure; thus, shape deformation cannot be avoided. This shape deformation results in shape differences between the surface of the mesh reflector and the ideal parabolic reflector, thus resulting in the degradation of the performance of the mesh reflector antenna. To observe this degradation, we analyze antenna performance according to the number of arms, the number of joints, the feed distance, and the distance from the reflector center to each joint. The performance of the mesh reflector antenna is examined using an effective lossy conducting surface (ELCS) that has the same reflectivity as the silver-coated Teflon mesh to reduce simulation time and computing resources. The designed silver-coated Teflon mesh reflector and the double-ridged feed antenna are fabricated, and the bore-sight gain is measured using the three-antenna method. The measured bore-sight gain of the proposed antenna is 31.6 dBi at 10 GHz, and the measured and simulated results show an average difference of 3.28 dB from 2 GHz to 18 GHz. The proposed deployable mesh reflector antenna can be used in a variety of applications where small stowed volume is required for mobility, such as mobile high-gain antennas as well as satellite antenna systems. Through this study, we demonstrate that shape deformation of the mesh reflector surface significantly affects the performance of reflector antennas.

4.
Front Cardiovasc Med ; 10: 1253177, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38075963

RESUMO

The presence of residual activated coagulation factor XI (FXIa) in some commercial intravenous immunoglobulin (IVIG) products has been identified as the root cause of a small number of thromboembolic events in patients who had received such therapy. Our objectives here were to design and evaluate the manufacturing process of GC5107, a 10% glycine-stabilized IVIG product, for its capacity to remove FXIa. The manufacturing process included a cation exchange chromatography (CEX) step, which employs a resin that binds immunoglobulin G (IgG) with high capacity. Procoagulant activity was assessed using Western blot analysis, enzyme-linked immunosorbent assay, thrombin generation assay, chromogenic FXIa assay, and non-activated partial thromboplastin time (NaPTT) assay. A spiking study in which large quantities of FXIa were added to samples before CEX chromatography was used to examine the robustness of the process to remove FXIa. Western blot and ELISA analyses demonstrated that residual FXIa remained in the intermediate manufacturing products until after CEX chromatography, when it was reduced to undetectable levels. The spiking study demonstrated that CEX chromatography removed >99% of FXI protein and reduced FXI activity to below detection limits, even in samples containing 158-fold greater FXIa levels than that of normal samples. Procoagulant activity in 9 consecutive lots of GC5107 was reduced to below the detection limits of the thrombin generation and chromogenic FXIa assays (<1.56 IU/ml and <0.16 IU/ml, respectively). The NaPTT of >250 s in all 9 lots indicated very low levels of procoagulant activity. We demonstrate that a novel 10% IVIG manufacturing process including CEX chromatography is a robust means of removing FXIa from the final preparation.

5.
Health Commun ; 38(7): 1359-1372, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-34894918

RESUMO

Health literacy is an important social determinant of health. Achieving health literacy of immigrants can be critical to empower this disadvantaged population in healthcare communication. However, to achieve this goal, it is a prerequisite to examine the relationship between health literacy and patient engagement in healthcare communication. This systematic review conceptualizes behavioral, emotional, and cognitive dimensions of patient engagement in healthcare communication and examines how health literacy and patient engagement among immigrants shape each other. A systematic review was conducted to identify relevant articles from five databases between 2010 and 2020. The reviewers synthesized findings from 15 articles that met the inclusion criteria. The results indicate that communication researchers should be more attentive to the emotional dimension of patient engagement in healthcare communication and that more empirical studies are needed to evaluate the relationship between health literacy and patient engagement among immigrants. Practical implications and recommendations for future research are discussed.


Assuntos
Emigrantes e Imigrantes , Letramento em Saúde , Humanos , Letramento em Saúde/métodos , Participação do Paciente
6.
Antioxidants (Basel) ; 10(11)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34829563

RESUMO

Unpredictable climate change might cause serious lack of food in the world. Therefore, in the present world, it is urgent to prepare countermeasures to solve problems in terms of human survival. In this research, quantitative trait loci (QTLs) were analyzed when rice attacked by white backed planthopper (WBPH) were analyzed using 120 Cheongcheong/Nagdong double haploid lines. Moreover, from the detected QTLs, WBPH resistance-related genes were screened in large candidate genes. Among them, OsCM, a major gene in the synthesis of Cochlioquinone-9 (cq-9), was screened. OsCM has high homology with the sequence of chorismate mutase, and exists in various functional and structural forms in plants that produce aromatic amino acids. It also induces resistance to biotic stress through the synthesis of secondary metabolites in plants. The WBPH resistance was improved in rice overexpressed through map-based cloning of the WBPH resistance-related gene OsCM, which was finally detected by QTL mapping. In addition, cq-9 increased the survival rate of caecal ligation puncture (CLP)-surgery mice by 60%. Moreover, the aorta of rat treated with cq-9 was effective in vasodilation response and significantly reduced the aggregation of rat platelets induced by collagen treatment. A cq-9, which is strongly associated with resistance to WBPH in rice, is also associated with positive effect of CLP surgery mice survival rate, vasodilation, and significantly reduced rat platelet aggregation induced by collagen treatment. Therefore, cq-9 presents research possibilities as a substance in a new paradigm that can act on both Plant-Insect in response to the present unpredictable future.

7.
Sensors (Basel) ; 21(20)2021 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-34696100

RESUMO

This paper proposes a novel wideband leaf-shaped printed dipole antenna sensor that uses a parasitic element to improve the impedance matching bandwidth characteristics for high-power jamming applications. The proposed antenna sensor consists of leaf-shaped dipole radiators, matching posts, rectangular slots, and a parasitic loop element. The leaf-shaped dipole radiators are designed with exponential curves to obtain a high directive pattern and are printed on a TLY-5 substrate for high-power durability. The matching posts, rectangular slots, and a parasitic loop element are used to enhance the impedance matching characteristics. The proposed antenna sensor has a measured fractional bandwidth of 66.7% at a center frequency of 4.5 GHz. To confirm the array antenna sensor characteristics, such as its active reflection coefficients (ARCs) and beam steering gains, the proposed single antenna sensor is extended to an 11 × 1 uniform linear array. The average values of the simulated and measured ARCs from 4.5 to 6 GHz are -13.4 dB and -14.7 dB. In addition, the measured bore-sight array gains of the co-polarization are 13.4 dBi and 13.7 dBi at 4 GHz and 5 GHz, while those of the cross-polarizations are -4.9 dBi and -3.4 dBi, respectively. When the beam is steered at a steering angle, θ0, of 15°, the maximum measured array gains of the co-polarization are 12.2 dBi and 10.3 dBi at 4 GHz and 5 GHz, respectively.


Assuntos
Impedância Elétrica , Tecnologia sem Fio , Desenho de Equipamento
8.
Foods ; 10(6)2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34205436

RESUMO

To investigate the adipogenesis and lipolysis effects of the Bacillus subtilis-fermented white sword bean extract (FWSBE) on 3T3-L1 adipocytes, we treated 3T3-L1 preadipocytes before and after differentiation with FWSBE and measured triglyceride, free glycerol, mRNA, and protein levels. First, FWSBE reduced the cell viability of 3T3-L1 pre-adipocytes under 1000 µg/mL conditions. Triglyceride accumulation in 3T3-L1 pre-adipocytes was suppressed, and free glycerol content in mature 3T3-L1 adipocytes was increased in the FWSBE treatment groups, indicating that FWSBE has anti-obesity effects. Further, FWSBE suppressed adipogenesis in 3T3-L1 pre-adipocytes by lowering the protein levels of C/EBPα, PPARγ, and FAS and increasing the level of pACC and pAMPK. Additionally, FWSBE promoted lipolysis in mature 3T3-L1 adipocytes by increasing the transcription levels of Ppara, Acox, and Lcad and the protein levels of pHSL and ATGL. Thus, we suggest that FWSBE can be a potential dietary supplement because of its anti-obesity properties.

9.
Ultrason Sonochem ; 71: 105382, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33276234

RESUMO

Hydrodynamic cavitation is a powerful tool for the enhancement of various processing applications. This study utilizes continuous hydrodynamic cavitation (CHC) for the inactivation of pathogens in milk for the first time. The thermal characteristics, inactivation performance, damage on the nutritional composition, product safety, and cost of the advanced rotational hydrodynamic cavitation reactor at pilot scale were comprehensively investigated. The inactivation results demonstrated that 5.89, 5.53, and 2.99 ± 0.08 log reductions of Escherichia coli, Staphylococcus aureus, and Bacillus cereus were achieved, respectively, at a final treatment temperature of 70 °C for 1-2 s. Moreover, the detrimental effect of CHC on the nutritional composition of milk, including mineral, fat, protein, and vitamin contents, was similar to that of high-temperature short-time method. The change in the concentrations of general bacteria and E. coli, as well as the pH value and acidity of the CHC treated milk stored at 5 °C for 14 days was found to be close to that of low-temperature long-time pasteurized milk. The cost of the present CHC treatment was $0.00268/L with a production rate of 4.2 L/min. CHC appears to be a remarkable method for the continuous processing of milk, as well as other liquid foods with high nutrition and "fresh-picked" flavor, due to its high efficacy, good scalability, high production capacity, and low operating and equipment costs.


Assuntos
Manipulação de Alimentos/instrumentação , Hidrodinâmica , Viabilidade Microbiana , Leite/microbiologia , Animais , Concentração de Íons de Hidrogênio , Valor Nutritivo
10.
Int J Biol Macromol ; 153: 169-179, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32105695

RESUMO

Lotus leaf polysaccharides were extracted by enzyme-assisted extraction using α-amylase (LLEP-A), cellulose (LLEP-C), pectinase (LLEP-P) or protease (LLEP-PR). Their physicochemical properties and immunostimulatory activities were compared with those of hot-water extracted polysaccharides (LLWP). HPAEC-PDA and HPSEC-RI profiles indicated that variations in their molecular weight patterns and chemical compositions. Moreover, their effects on proliferation, phagocytic activity, and cytokine production in macrophages could be ordered as LLEP-P > LLEP-C > LLEP-A > LLWP > LLEP-PR, suggesting that LLEP-P by pectinase-assisted extraction was the most potent enhancer of macrophage activation. LLEP-P was further purified by gel filtration, and the main fraction (LLEP-P-І) was obtained to elucidate the structural and functional properties. LLEP-P-І (14.63 × 103 g/mol) mainly consisted of rhamnose, arabinose, galactose, and galacturonic acid at molar percentages of 15.5:15.8:20.1:32.8. FT-IR spectra indicated the predominant acidic and esterified form, suggesting the pectic-like structure. Above all, LLEP-P-І exerted greater stimulation effects on NO and cytokines production and the phagocytic activity in macrophages. Transcriptome analysis also demonstrated that LLEP-P and LLEP-P-І could upregulate macrophage immune response genes, including cytokines, chemokines, and interferon via TLR and JAK-STAT signaling. Thus, these results suggest that pectinase application is most suitable to obtain immunostimulatory polysaccharides from lotus leaves.


Assuntos
Adjuvantes Imunológicos , Lotus/química , Macrófagos/imunologia , Folhas de Planta/química , Polissacarídeos , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/isolamento & purificação , Adjuvantes Imunológicos/farmacologia , Animais , Configuração de Carboidratos , Citocinas/imunologia , Macrófagos/citologia , Camundongos , Óxido Nítrico/imunologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Células RAW 264.7
11.
Rice (N Y) ; 12(1): 87, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776807

RESUMO

BACKGROUND: Rice is one of the few cereals consumed as a whole grain, and therefore the appearance of the final milled product, both before and after cooking, strongly influences the consumer's perception of product quality. Matching consumer preference for rice grain quality is a key component of rice variety development programs, as the quality drives demand, which in turn drives variety adoption, market price, and profitability. The quality of cooked rice is normally evaluated indirectly, through measurement of key elements driving quality as well as more directly by sensory evaluation, but remains a complex trait conditioned by the genetic complexity of factors driving quality, changes wrought by environment, and the complexity of consumer preferences. RESULT: In this study, we evaluated 17 traits, including the taste value obtained by glossiness of cooked rice (TV), to explain rice eating quality by statistical methods and identified QTLs associated with TV. To explain the correlation among traits, exploratory factor analysis was performed for 2 years. The overall eating quality (OE) was correlated with TV and protein content loading at the same factor (PA1) in 2017, and there was a relationship between the OE (PA1) and the TV (PA2) in 2018 (PA1:PA2, r = 0.3). In QTL analysis using 174 RILs, three QTLs for TV derived from Wandoaengmi6 were detected on chromosomes 4, 6, and 9. The QTL qTV9 delimited within Id9007180 and 9,851,330 on chromosome 9 was detected in both years, explaining approximately 17% of the variation, on average. Through the use of fine mapping, qTV9 was delimited to an approximately 34-Kbp segment flanked by the DNA markers CTV9_9 and CTV9_13, and nine ORFs were listed in the target region as candidate genes associated with TV. In the evaluation of qTV9's effect on OE, the lines with qTV9 showed a significant increase in correlation coefficiency compared to the negative lines. These data will apply to functional analysis on the glossiness and the MAS breeding program to improve the eating quality of japonica as a donor line. CONCLUSION: In this paper we report a number of QTL associated with changes in glossiness of cooked rice, and these may have utility in the development of MAS in breeding programs with a specific focus on cooked grain quality.

12.
Nutr Res Pract ; 11(6): 487-491, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29209459

RESUMO

BACKGROUND/OBJECTIVES: Although globally the numbers of children diagnosed with failure to thrive (FTT) have decreased, FTT is still a serious pediatric problem. We aimed to investigate the effects of zinc supplementation for 6 months on growth parameters of infants and children with FTT. SUBJECTS/METHODS: In this retrospective study, of the 114 participants aged between 4 months and 6 years, 89 were included in the zinc supplementation group and were provided with nutrition counseling plus an oral zinc supplement for 6 months. The caregivers of the 25 participants in the control group received nutrition counseling alone. Medical data of these children, including sex, age, height, weight, serum zinc level, and serum insulin-like growth factor 1 (IGF1) level were analyzed. RESULTS: Zinc supplementation for 6 months increased weight-for-age Z-score and serum zinc levels (5.5%) in the zinc supplementation group of underweight category children. As for stunting category, height-for-age Z-score of the participants in the zinc supplementation group increased when compared with the baseline, and serum zinc levels increased in the normal or mild stunting group. Serum IGF1 levels did not change significantly in any group. Thus, zinc supplementation was more effective in children in the underweight category than those in the stunted category; this effect differed according to the degree of the FTT. CONCLUSION: These findings suggest that zinc supplementation may have beneficial effects for growth of infants and children with FTT, and zinc supplementation would be required according to degree of FTT.

13.
Chem Asian J ; 8(2): 400-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23208797

RESUMO

A series of heterocycle-linked constrained phenylbenzyl amides were found to be TRPV1 antagonists with promising in vivo profiles. In particular, one of the analogues containing a furan linker exhibited excellent TRPV1 antagonistic activity and in vivo analgesic efficacy. In addition, the binding modes of dibenzyl thiourea, benzylphenethyl amide, and furan-linked phenylbenzyl amide were examined by using the flexible docking study within the rTRPV1 homology model.


Assuntos
Amidas/química , Compostos Heterocíclicos/química , Canais de Cátion TRPV/antagonistas & inibidores , Amidas/farmacocinética , Amidas/uso terapêutico , Analgésicos/síntese química , Analgésicos/farmacocinética , Analgésicos/uso terapêutico , Animais , Sítios de Ligação , Furanos/química , Meia-Vida , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Masculino , Simulação de Acoplamento Molecular , Estrutura Terciária de Proteína , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo , Tioureia/química
14.
J Med Chem ; 55(19): 8392-408, 2012 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-22957803

RESUMO

A series of N-(2-amino-6-trifluoromethylpyridin-3-ylmethyl)-2-(3-fluoro-4-methylsulfonylaminophenyl)propanamides were designed combining previously identified pharmacophoric elements and evaluated as hTRPV1 antagonists. The SAR analysis indicated that specific hydrophobic interactions of the 2-amino substituents in the C-region of the ligand were critical for high hTRPV1 binding potency. In particular, compound 49S was an excellent TRPV1 antagonist (K(i(CAP)) = 0.2 nM; IC(50(pH)) = 6.3 nM) and was thus approximately 100- and 20-fold more potent, respectively, than the parent compounds 2 and 3 for capsaicin antagonism. Furthermore, it demonstrated strong analgesic activity in the rat neuropathic model superior to 2 with almost no side effects. Compound 49S antagonized capsaicin induced hypothermia in mice but showed TRPV1-related hyperthermia. The basis for the high potency of 49S compared to 2 is suggested by docking analysis with our hTRPV1 homology model in which the 4-methylpiperidinyl group in the C-region of 49S made additional hydrophobic interactions with the hydrophobic region.


Assuntos
Analgésicos/síntese química , Piridinas/síntese química , Sulfonamidas/síntese química , Canais de Cátion TRPV/antagonistas & inibidores , Analgésicos/química , Analgésicos/farmacologia , Animais , Temperatura Corporal/efeitos dos fármacos , Células CHO , Capsaicina/farmacologia , Cricetinae , Cricetulus , Dopamina/análogos & derivados , Dopamina/farmacologia , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Simulação de Acoplamento Molecular , Neuralgia/tratamento farmacológico , Piridinas/química , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Estereoisomerismo , Relação Estrutura-Atividade , Sulfonamidas/química , Sulfonamidas/farmacologia , Canais de Cátion TRPV/genética
15.
Bioorg Med Chem Lett ; 22(11): 3656-60, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22546668

RESUMO

The structure-activity relationships of N-(3-acyloxy-2-benzylpropyl)-N'-4-[(methylsulfonylamino)benzyl] thioureas, which represent simplified RTX-based vanilloids, were investigated by varying the distances between the four principal pharmacophores and assessing binding and antagonistic activity on rTRPV1. The analysis indicated that a 3-pivaloyloxy-2-benzylpropyl C-region conferred the best potency in binding affinity and antagonism. The molecular modeling of this best template with the tetrameric homology model of rTRPV1 was performed to identify its binding interactions with the receptor.


Assuntos
Simulação de Dinâmica Molecular , Canais de Cátion TRPV/antagonistas & inibidores , Tioureia/química , Animais , Sítios de Ligação , Células CHO , Cricetinae , Cricetulus , Estrutura Terciária de Proteína , Ratos , Relação Estrutura-Atividade , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/metabolismo , Tioureia/síntese química
16.
J Med Chem ; 55(1): 342-56, 2012 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-22142423

RESUMO

Truncated N(6)-substituted-4'-oxo- and 4'-thioadenosine derivatives with C2 or C8 substitution were studied as dual acting A(2A) and A(3) adenosine receptor (AR) ligands. The lithiation-mediated stannyl transfer and palladium-catalyzed cross-coupling reactions were utilized for functionalization of the C2 position of 6-chloropurine nucleosides. An unsubstituted 6-amino group and a hydrophobic C2 substituent were required for high affinity at the hA(2A)AR, but hydrophobic C8 substitution abolished binding at the hA(2A)AR. However, most of synthesized compounds displayed medium to high binding affinity at the hA(3)AR, regardless of C2 or C8 substitution, and low efficacy in a functional cAMP assay. Several compounds tended to be full hA(2A)AR agonists. C2 substitution probed geometrically through hA(2A)AR docking was important for binding in order of hexynyl > hexenyl > hexanyl. Compound 4g was the most potent ligand acting dually as hA(2A)AR agonist and hA(3)AR antagonist, which might be useful for treatment of asthma or other inflammatory diseases.


Assuntos
Agonistas do Receptor A2 de Adenosina/síntese química , Antagonistas do Receptor A3 de Adenosina/síntese química , Adenosina/análogos & derivados , Adenosina/síntese química , Receptor A3 de Adenosina/metabolismo , Receptores A2 de Adenosina/metabolismo , Tiofenos/síntese química , Adenosina/farmacologia , Agonistas do Receptor A2 de Adenosina/farmacologia , Antagonistas do Receptor A3 de Adenosina/farmacologia , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/farmacologia , Células CHO , Cricetinae , Cricetulus , AMP Cíclico/biossíntese , Células HEK293 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Masculino , Modelos Moleculares , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Estereoisomerismo , Relação Estrutura-Atividade , Tiofenos/farmacologia
17.
Bioorg Med Chem Lett ; 21(1): 299-302, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21111618

RESUMO

A series of 5'-halogenated resiniferatoxin analogs have been investigated in order to examine the effect of halogenation in the A-region on their binding and the functional pattern of agonism/antagonism for rat TRPV1 heterologously expressed in Chinese hamster ovary cells. Halogenation at the 5-position in the A-region of RTX and of 4-amino RTX shifted the agonism of parent compounds toward antagonism. The extent of antagonism was greater as the size of the halogen increased (I > Br > Cl > F) while the binding affinities were similar, as previously observed for our potent agonists. In this series, 5-bromo-4-amino RTX (39) showed very potent antagonism with K(i) (ant) = 2.81 nM, which was thus 4.5-fold more potent than 5'-iodo RTX, previously reported as a potent TRPV1 antagonist. Molecular modeling analyses with selected agonists and the corresponding halogenated antagonists revealed a striking conformational difference. The 3-methoxy of the A-region in the agonists remained free to interact with the receptor whereas in the case of the antagonists, the compounds assumed a bent conformation, permitting the 3-methoxy to instead form an internal hydrogen bond with the C4-hydroxyl of the diterpene.


Assuntos
Diterpenos/química , Canais de Cátion TRPV/antagonistas & inibidores , Animais , Células CHO , Cricetinae , Cricetulus , Diterpenos/síntese química , Diterpenos/farmacologia , Halogenação , Ligantes , Modelos Moleculares , Ratos , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/metabolismo
18.
Bioorg Med Chem ; 18(19): 7015-21, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20826090

RESUMO

We synthesized homologated truncated 4'-thioadenosine analogues 3 in which a methylene (CH(2)) group was inserted in place of the glycosidic bond of a potent and selective A(3) adenosine receptor antagonist 2. The analogues were designed to induce maximum binding interaction in the binding site of the A(3) adenosine receptor. However, all homologated nucleosides were devoid of binding affinity at all subtypes of adenosine receptors, indicating that free rotation through the single bond allowed the compound to adopt an indefinite number of conformations, disrupting the favorable binding interaction essential for receptor recognition.


Assuntos
Antagonistas do Receptor A3 de Adenosina/síntese química , Antagonistas do Receptor A3 de Adenosina/farmacologia , Adenosina/análogos & derivados , Desenho de Fármacos , Receptor A3 de Adenosina/metabolismo , Tionucleosídeos/síntese química , Tionucleosídeos/farmacologia , Adenosina/síntese química , Adenosina/química , Adenosina/farmacologia , Antagonistas do Receptor A3 de Adenosina/química , Sítios de Ligação , Humanos , Modelos Moleculares , Conformação Molecular , Receptor A3 de Adenosina/química , Estereoisomerismo , Relação Estrutura-Atividade , Tionucleosídeos/química
19.
ACS Med Chem Lett ; 2010(9): 516-520, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21286238

RESUMO

The truncated C2- and C8-substituted-4'-thioadenosine derivatives 4a-d were synthesized from D-mannose, using palladium-catalyzed cross coupling reactions as key steps. In this study, an A(3) adenosine receptor (AR) antagonist, truncated 4'-thioadenosine derivative 3 was successfully converted into a potent A(2A)AR agonist 4a (K(i) = 7.19 ± 0.6 nM) by appending a 2-hexynyl group at the C2-position of a derivative of 3 that was N(6)-substituted. However, C8-substitution greatly reduced binding affinity at the human A(2A)AR. All synthesized compounds 4a-d maintained their affinity at the human A(3)AR, but 4a was found to be a competitive A(3)AR antagonist/A(2A)AR agonist in cyclic AMP assays. This study indicates that the truncated C2-substituted-4'-thioadenosine derivatives 4a and 4b can serve as a novel template for the development of new A(2A)AR ligands.

20.
Bioorg Med Chem ; 16(22): 9772-9, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18930405

RESUMO

The abnormal proliferation and migration of vascular smooth muscle cells (SMCs) play an important role in the pathology of coronary artery atherosclerosis and restenosis following angioplasty. It was reported that some heterocyclic quinone derivatives such as 6-arylamino-quinoxaline-5,8-diones and 6-arylamino-1H-benzo[d]imidazole-4,7-diones have inhibitory activity on rat aortic smooth muscle cell (RAoSMC) proliferation. To understand the structural basis for antiproliferative activity to design more potent agents, we generated pharmacophore models of representative molecules with high activity using Genetic Algorithm with Linear Assignment of Hypermolecular Alignment of Database (GALAHAD) and aligned a series of compounds to the selected pharmacophore model, then performed three-dimensional quantitative structure-activity relationship (3D-QSAR) studies using Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Indices Analysis (CoMSIA). Good cross-validated correlations were obtained with CoMFA (resulting in q(2) of 0.734 and r(2) of 0.947) and CoMSIA (resulting in q(2) of 0.736 and r(2) of 0.913). The IC(50) values of the heterocyclic quinone derivatives on RAoSMC exhibited a strong correlation with steric and hydrophobic fields of the 3D structure of the molecules, resulting in the reliable prediction of inhibitory activity of the series of compounds.


Assuntos
Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Quinonas/química , Quinonas/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Simulação por Computador , Desenho de Fármacos , Concentração Inibidora 50 , Modelos Moleculares , Estrutura Molecular , Músculo Liso Vascular/citologia , Relação Quantitativa Estrutura-Atividade , Quinonas/síntese química , Ratos
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