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1.
Phys Chem Chem Phys ; 19(13): 8896-8901, 2017 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-28294253

RESUMEN

Small organic molecules based on the unnatural DNA base pair dTPT3 are designed and synthesized, among which compounds bearing the thiocarbonyl group, compared with their carbonyl counterparts, show a much larger SOC integral between S1(1nπ*) and T1(3ππ*) states due to the appropriate energy level alignment and the heavy sulfur atom effect, resulting in the appearance of both fluorescence and phosphorescence in solution and solid state at room temperature.

2.
Phys Chem Chem Phys ; 19(42): 28641-28646, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29058008

RESUMEN

1,8-Dihydroxynaphthalene-2,7-dicarbaldehyde (DHDA) has been strategically designed and synthesized with the aim to study the competitive multiple hydrogen bonding (H-bonding) effect and the associated excited-state intramolecular proton transfer reaction (ESIPT). In nonpolar solvents such as cyclohexane, equilibrium exists between the two H-bonding isomers DHDA-23_OO and DHDA-23_OI, both of which possess double intramolecular H-bonds. In polar, aprotic solvents such as CH2Cl2, DHDA-23_OO becomes the predominant species. Due to various degrees of H-bond induced changes of electronic configuration each isomer reveals a distinct absorption feature and excited-state behavior, in which DHDA-23_OI in cyclohexane undergoes double ESIPT in a stepwise manner, giving the first and second proton-transfer tautomer emissions maximized at ∼500 nm and 660 nm, respectively. As for DHDA-23_OO both single and double ESIPT are prohibited, resulting in an intense normal 450 nm emission band. In a single crystal DHDA-23_OI is the dominant species, which undergoes excited state double proton transfer, giving intense emission bands at 530 nm and 650 nm. The mechanism associated with competitive multiple H-bonding energetics and ESIPT was underpinned by detailed spectroscopy/dynamics and computational approaches.

3.
Phys Chem Chem Phys ; 18(35): 24428-36, 2016 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-27537476

RESUMEN

A series of new amino (NH)-type intramolecular hydrogen-bonding (H-bonding) compounds have been strategically designed and synthesized. These molecules comprise a 2-(imidazo[1,2-a]pyridin-2-yl)aniline moiety, in which one of the amino hydrogens was replaced with substituents of different electronic properties. This, together with the versatile capability for modifying the parent moiety, makes feasible comprehensive spectroscopy and dynamics studies of excited-state intramolecular proton transfer (ESIPT) as a function of N-H acidity. Different from other (NH)-type ESIPT systems where the ESIPT rate and exergonicity increase with an increase in the N-H acidity and hence the H-bonding strength, the results reveal an irregular relationship among ESIPT dynamics, thermodynamics and H-bond strength. This discrepancy may be rationalized by the localized zwitterionic nature of 2-(imidazo[1,2-a]pyridin-2-yl)aniline in the proton-transfer tautomer form, which is different from the π-delocalized tautomer form in other (NH)-type ESIPT systems.

4.
J Am Chem Soc ; 137(45): 14349-57, 2015 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-26493857

RESUMEN

1,8-Dihydroxy-2-naphthaldehyde (DHNA), having doubly intramolecular hydrogen bonds, was strategically designed and synthesized in an aim to probe a long-standing fundamental issue regarding synchronous versus asynchronous double-proton transfer in the excited state. In cyclohexane, DHNA shows the lowest lying S0 →S1 (π-π*) absorption at ∼400 nm. Upon excitation, two large Stokes shifted emission bands maximized at 520 and 650 nm are resolved, which are ascribed to the tautomer emission resulting from the first and second proton-transfer products, denoted by TA* and TB*, respectively. The first proton transfer (DHNA* → TA*) is ultrafast (< system response of 150 fs), whereas the second proton transfer is reversible, for which the rates of forward (TA* → TB*) and backward (TA* ← TB*) proton transfer were determined to be (1.7 ps)(-1) and (3.6 ps)(-1), respectively. The fast equilibrium leads to identical population lifetimes of ∼54 ps for both TA* and TB* tautomers. Similar excited-state double-proton transfer takes place for DHNA in a single crystal, resulting in TA* (560 nm) and TB* (650 nm) dual-tautomer emission. A comprehensive 2D plot of reaction potential energy surface further proves that the sequential two-step proton motion is along the minimum energetic pathway firmly supporting the experimental results. Using DHNA as a paradigm, we thus demonstrate unambiguously a stepwise, proton-relay type of intramolecular double-proton transfer reaction in the excited state, which should gain fundamental understanding of the multiple proton transfer reactions.

5.
Pediatr Neonatol ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38910078

RESUMEN

BACKGROUND AND PURPOSE: Parents of preterm infants experience anxiety and stress in the neonatal intensive care unit (NICU). Visitation restrictions due to COVID-19 have increased maternal pressure and limited bonding opportunities. Little research exists in Taiwan on using video conferencing as a solution. This study investigates depression and stress levels in mothers of preterm infants and evaluates the effectiveness of video visitation during NICU restrictions. METHODS: This study adopts a cross-sectional design and a qualitative survey. Mothers of premature infants were recruited and they participated in the study. Interventions for video visits were scheduled on the third day of admission to the NICU (T1) and during the second week of the study (T2). After each video visit, participants completed an online survey. The study's online survey used structured questionnaires including demographics, the Edinburgh Postnatal Depression Scale (EPDS) and the Parental Stress Scale (PSS): Infant Hospitalization (IH). RESULTS: A total of 51 mothers of preterm infants participated in the study. During the T1 and T2 periods, single mothers with lower educational levels and those aged below 30 experienced depression and high levels of stress. Lower birth weight and gestational age were associated with maternal depression. Video visitation intervention led to a significant decrease in depression scores (EPDS, T1: 11.3 ± 5.5 vs. T2: 10.1 ± 5.2, p = 0.039). Positive correlations were observed between EPDS and PSS: IH scores (p < 0 .005). CONCLUSION: Video visitation intervention can reduce maternal depression in mothers with preterm infants. Since it is practical, video visitation may be applied even after the pandemic.

6.
Neuropsychiatr Dis Treat ; 20: 597-606, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38496324

RESUMEN

Introduction: The coronavirus disease 2019 (COVID-19) pandemic has had an impact on patients with substance use disorder (SUD). We aimed to investigate factors associated with confidence and adherence to governmental policies against COVID-19 (social desirability) among patients with SUD. Methods: This cross-sectional study was conducted during 2020 to 2021. Patients with SUD and healthy controls were recruited. The severity of sleep disturbance, social desirability, drug dependence, vaccine worries, other psychological burdens and demographic variables were collected through self-administrated questionnaires. Differences between the SUD and control groups were estimated. Hierarchical regression analysis was used to identify significant relationships between social desirability and other factors. Results: In total, 58 of patients with SUD and 47 healthy controls were recruited. The patients with SUD had a lower level of social desirability and more severe sleep disturbance than the control group. Older age, more severe sleep disturbance, lower level of drug dependence, and lower level of vaccine worries were significantly associated with a higher level of social desirability among the patients with SUD. Conclusion: Our results show the importance of timely interventions for drug dependence and to address vaccine worries in patients with SUD.

7.
Medicine (Baltimore) ; 101(42): e31316, 2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36281087

RESUMEN

The coronavirus disease 2019 (COVID-19) pandemic has caused a heavily burden on healthcare workers (HCWs) worldwide. The aim of this study was to compare differences in psychological and social impact between two waves of the pandemic among first- and second-line HCWs in Taiwan. The current study derived data from two cross-sectional surveys conducted in 2020 and 2021. Levels of depression, sleep disturbance, psychological distress, social impact, and demographic variables were collected through self-reported questionnaires. The independent t test was used to compare differences in scores between the first and second wave of the pandemic. Differences between first- and second-line HCWs were also analyzed. A total of 711 HCWs in the first wave and 560 HCWs in the second wave were recruited. For the first- and second-line HCWs, the social impact during the second wave was higher than during the first wave, and they expressed a higher intention to maintain social distancing and were more aware of the pandemic overseas in the second wave. The first-line HCWs had a trend of worse sleep quality during the second wave. In addition, sleep quality was worse in the first-line HCWs than in the second-line HCWs during both waves. The second-line HCWs expressed a greater desire to seek COVID-19-related information than the first-line HCWs during the first wave, and more intended to maintain social distancing during the second wave. Our results show the importance of evaluating the social and mental health burden of HCWs, and especially first-line workers.


Asunto(s)
COVID-19 , Pandemias , Humanos , COVID-19/epidemiología , Estudios Transversales , Taiwán/epidemiología , Personal de Salud/psicología
8.
Artículo en Inglés | MEDLINE | ID: mdl-35954849

RESUMEN

Vaccine hesitancy has become a major public health problem among healthcare workers (HCWs) in this coronavirus disease 2019 (COVID-19) pandemic. The aim of this study was to examine the relationship between societal adaptation and vaccine worries and the mediating effects of posttraumatic stress disorder (PTSD) indicators in HCWs. A total of 435 HCWs (327 women and 108 men) were recruited. Their levels of societal adaptation were evaluated using the Societal Influences Survey Questionnaire (SISQ). Their severity and frequency of PTSD symptoms were examined using the Disaster-Related Psychological Screening Test (DRPST). The severity of vaccine worries was assessed using the Vaccination Attitudes Examination (VAX) Scale. The relationships among societal adaptation, PTSD, and vaccine worries were examined using structural equation modeling. The severity of societal adaptation was positively associated with both the severity of PTSD and the severity of vaccine worries. In addition, the severity of PTSD indicators was positively associated with the severity of vaccine worries. These results demonstrated that the severity of societal adaptation was related to the severity of vaccine worries, either directly or indirectly. The indirect relationship was mediated by the severity of PTSD. Societal adaptation and PTSD should be taken into consideration by the community of professionals working on vaccine hesitancy. Early detection and intervention of PTSD should be the objectives for programs aiming to lower vaccine hesitancy among HCWs.


Asunto(s)
COVID-19 , Trastornos por Estrés Postraumático , Vacunas , COVID-19/epidemiología , Femenino , Personal de Salud/psicología , Humanos , Masculino , Pandemias , Trastornos por Estrés Postraumático/epidemiología , Trastornos por Estrés Postraumático/psicología
9.
Sci Rep ; 10(1): 3953, 2020 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-32127576

RESUMEN

Recent advances in high-throughput genomic technologies have nurtured a growing demand for statistical tools to facilitate identification of molecular changes as potential prognostic biomarkers or drugable targets for personalized precision medicine. In this study, we developed a web-based interactive and user-friendly platform for high-dimensional analysis of molecular alterations in cancer (HDMAC) (https://ripsung26.shinyapps.io/rshiny/). On HDMAC, several penalized regression models that are suitable for high-dimensional data analysis, Ridge, Lasso and adaptive Lasso, are offered, with Cox regression for survival and logistic regression for binary outcomes. Choice of a first-step screening is provided to address the multiple-comparison issue that often arises with large-volume genomic data. Hazard ratio or estimated coefficient is provided with each selected gene so that a multivariate regression model may be built based on the genes selected. Cross validation is provided as the method to estimate the prediction power of each regression model. In addition, R codes are also provided to facilitate download of whole sets of molecular variables from TCGA. In this study, illustration of the use of HDMAC was made through a set of data on gene mutations and a set on mRNA expression from ovarian cancer patients and a set on mRNA expression from bladder cancer patient. From the analysis of each set of data, a list of candidate genes was obtained that might be associated with mutations or abnormal expression of genes in ovarian and bladder cancers. HDMAC offers a solution for rigorous and validation analysis of high-dimensional genomic data.


Asunto(s)
Neoplasias/genética , Neoplasias/metabolismo , Femenino , Humanos , Modelos Logísticos , Modelos Teóricos , Análisis Multivariante , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Modelos de Riesgos Proporcionales , ARN Mensajero/genética , ARN Mensajero/metabolismo
10.
Chem Asian J ; 12(23): 3010-3015, 2017 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-28980416

RESUMEN

Searching for eight-membered ring π-conjugated hydrogen bonding (8-MR H-bonding) systems with excited-state intramolecular proton transfer (ESIPT) property is seminal and synthetically challenging. In this work, a series of π-conjugated molecules (8-HB-1, 8-HB-L1 and 8-HB-2) potentially possessing 8-MR H-bonding are strategically designed, synthesized and characterized. The configurations of these three potential molecules are checked by their X-ray structures, among which 8-HB-L1 (a structurally locked 8-HB-1 core chromophore) is proved to be an 8-MR H-bonding system, whereas 8-HB-1 and 8-HB-2 are too sterically hindered to form the 8-MR intramolecular H-bond. The ESIPT property of 8-HB-L1 is confirmed by the dual fluorescence consisting of normal and proton-transfer tautomer emissions. The insight into the ESIPT process of 8-HB-L1 is provided by femtosecond fluorescence upconversion measurements together with computational simulation. The results demonstrate for the first time a successful synthetic route to attain the 8-MR H-bonding molecule 8-HB-L1 with ESIPT property.

11.
Am J Chin Med ; 42(3): 619-37, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24871655

RESUMEN

Expression of cell adhesion molecules by the endothelium and the attachment of leukocytes to these cells play major roles in inflammation and cardiovascular disorders. Magnolol, a major active component of Magnolia officinalis, has antioxidative and anti-inflammatory properties. In the present study, the effects of magnolol on the expression of vascular cell adhesion molecule-1 (VCAM-1) in human aortic endothelial cells (HAECs) and the related mechanisms were investigated. TNF-α induced VCAM-1 protein expression and mRNA stability were significantly decreased in HAECs pre-treated with magnolol. Magnolol significantly reduced the phosphorylation of ERK, JNK, and p38 in TNF-α-treated HAECs. The decrease in VCAM-1 expression in response to TNF-α treatment was affected by JNK and p38 inhibitors, not by an ERK inhibitor. Magnolol also attenuates NF-κB activation and the translocation of HuR (an RNA binding protein) in TNF-α-stimulated HAECs. The VCAM-1 expression was weaker in the aortas of TNF-α-treated apo-E deficient mice with magnolol treatment. These data demonstrate that magnolol inhibits TNF-α-induced JNK/p38 phosphorylation, HuR translocation, NF-κB activation, and thereby suppresses VCAM-1 expression resulting in reduced leukocyte adhesion. Taken together, these results suggest that magnolol has an anti-inflammatory property and may play an important role in the prevention of atherosclerosis and inflammatory responses.


Asunto(s)
Compuestos de Bifenilo/farmacología , Células Endoteliales/metabolismo , Expresión Génica/efectos de los fármacos , Expresión Génica/genética , Lignanos/farmacología , Sistema de Señalización de MAP Quinasas/genética , Sistema de Señalización de MAP Quinasas/fisiología , FN-kappa B/genética , FN-kappa B/fisiología , Transducción de Señal/genética , Transducción de Señal/fisiología , Factor de Necrosis Tumoral alfa/efectos adversos , Molécula 1 de Adhesión Celular Vascular/genética , Molécula 1 de Adhesión Celular Vascular/metabolismo , Animales , Antiinflamatorios , Antioxidantes , Aorta/citología , Aorta/efectos de los fármacos , Apolipoproteínas E/deficiencia , Aterosclerosis/prevención & control , Células Cultivadas , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Fosforilación/efectos de los fármacos , Fosforilación/genética , Fitoterapia , Transducción de Señal/efectos de los fármacos
12.
J Agric Food Chem ; 58(17): 9563-71, 2010 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-20687608

RESUMEN

The expression of adhesion molecules on vessels and subsequent leukocyte recruitment are critical events in vascular diseases and inflammation. The aim of the present study was to examine the effects of an extract of Ganoderma lucidum (Reishi) polysaccharides (EORP), which is effective against cancer and immunological disorders, on adhesion molecule expression by human aortic smooth muscle cells (HASMCs) and the underlying mechanism. EORP significantly suppressed lipopolysaccharide (LPS)-induced intercellular cell adhesion molecule-1 (ICAM-1) mRNA and protein expression and reduced the binding of human monocytes to LPS-stimulated HASMCs. Immunoprecipitation and real-time polymerase chain reaction demonstrated that EORP markedly reduced the interaction of human antigen R protein (HuR) with the 3'-UTR of ICAM-1 mRNA in LPS-stimulated HASMCs. EORP treatment also suppressed extracellular signal-regulated kinase (ERK) phosphorylation and reduced the density of the shifted bands of nuclear factor (NF)-kappaB after LPS-induced activation. In an endothelial-denuded artery model in LPS-treated mice, daily oral administration of EORP for 2 weeks decreased neointimal hyperplasia and ICAM-1 expression in the plasma and neointima. These results provide evidence that EORP attenuates LPS-induced adhesion molecule expression and monocyte adherence and that this protective effect is mediated by decreased ERK phosphorylation and NF-kappaB activation. These findings suggest that EORP has anti-inflammatory properties and could prove useful in the prevention of vascular diseases and inflammatory responses.


Asunto(s)
Endotoxinas/toxicidad , Molécula 1 de Adhesión Intercelular/metabolismo , Músculo Liso/efectos de los fármacos , Polisacáridos/farmacología , Reishi/química , Túnica Íntima/efectos de los fármacos , Animales , Células Cultivadas , Molécula 1 de Adhesión Intercelular/genética , Ratones , Músculo Liso/citología
13.
Mol Nutr Food Res ; 54(9): 1340-50, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20306475

RESUMEN

Sesame lignans have antioxidative and anti-inflammatory properties. We focused on the effects of the lignans sesamin and sesamol on the expression of endothelial-leukocyte adhesion molecules in tumor necrosis factor-alpha (TNF-alpha)-treated human aortic endothelial cells (HAECs). When HAECs were pretreated with sesamin (10 or 100 microM), the TNF-alpha-induced expression of intercellular cell adhesion molecule-1 (ICAM-1) was significantly reduced (35 or 70% decrease, respectively) by Western blotting. Sesamol was less effective at inhibiting ICAM-1 expression (30% decrease at 100 microM). Sesamin and sesamol reduced the marked TNF-alpha-induced increase in human antigen R (HuR) translocation and the interaction between HuR and the 3'UTR of ICAM-1 mRNA. Both significantly reduced the binding of monocytes to TNF-alpha-stimulated HAECs. Sesamin significantly attenuated TNF-alpha-induced ICAM-1 expression and cell adhesion by downregulation of extracellular signal-regulated kinase 1/2 and p38. Furthermore, in vivo, sesamin attenuated intimal thickening and ICAM-1 expression seen in aortas of apolipoprotein-E-deficient mice. Taken together, these data suggest that sesamin inhibits TNF-alpha-induced extracellular signal-regulated kinase/p38 phosphorylation, nuclear translocation of NF-kappaB p65, cytoplasmic translocalization of HuR and thereby suppresses ICAM-1 expression, resulting in reduced adhesion of leukocytes. These results also suggest that sesamin may prevent the development of atherosclerosis and inflammatory responses.


Asunto(s)
Aorta/efectos de los fármacos , Aterosclerosis/prevención & control , Dioxoles/farmacología , Dioxoles/uso terapéutico , Endotelio Vascular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Molécula 1 de Adhesión Intercelular/metabolismo , Lignanos/farmacología , Lignanos/uso terapéutico , Animales , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/uso terapéutico , Antígenos de Superficie/genética , Antígenos de Superficie/metabolismo , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Aorta/citología , Aorta/metabolismo , Aorta/patología , Apolipoproteínas E/genética , Aterosclerosis/metabolismo , Aterosclerosis/patología , Benzodioxoles/farmacología , Línea Celular , Células Cultivadas , Proteínas ELAV , Proteína 1 Similar a ELAV , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Humanos , Molécula 1 de Adhesión Intercelular/genética , Ratones , Ratones Noqueados , Monocitos/efectos de los fármacos , Fenoles/farmacología , ARN Mensajero/metabolismo , ARN Interferente Pequeño , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Distribución Aleatoria , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología
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