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1.
Cell Commun Signal ; 22(1): 14, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38183076

RESUMEN

R-spondins (RSPOs) are secreted signaling molecules that potentiate the Wnt/ß-catenin pathway by cooperating with Wnt ligands. RSPO1 is crucial in tissue development and tissue homeostasis. However, the molecular mechanism by which RSPOs activate Wnt/ß-catenin signaling remains elusive. In this study, we found that RSPOs could mediate the degradation of Axin through the ubiquitin-proteasome pathway. The results of Co-IP showed that the recombinant RSPO1 protein promoted the interaction between Axin1 and CK1ε. Either knockout of the CK1ε gene or treatment with the CK1δ/CK1ε inhibitor SR3029 caused an increase in Axin1 protein levels and attenuated RSPO1-induced degradation of the Axin1 protein. Moreover, we observed an increase in the number of associations of LRP6 with CK1ε and Axin1 following RSPO1 stimulation. Overexpression of LRP6 further potentiated Axin1 degradation mediated by RSPO1 or CK1ε. In addition, recombinant RSPO1 and Wnt3A proteins synergistically downregulated the protein expression of Axin1 and enhanced the transcriptional activity of the SuperTOPFlash reporter. Taken together, these results uncover the novel mechanism by which RSPOs activate Wnt/ß-catenin signaling through LRP6/CK1ε-mediated degradation of Axin.


Asunto(s)
Proteína Axina , Trombospondinas , Vía de Señalización Wnt , beta Catenina , Transporte Biológico , Proteína Wnt3A , Humanos , Trombospondinas/metabolismo
2.
J Biol Inorg Chem ; 28(6): 559-570, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37477757

RESUMEN

Two arene ruthenium(II) complexes [η6-(C6H6)Ru(pprip)Cl]PF6 (Ru1; pprip = 2-(3-phenyl-1H-pyrazol-4-yl)-imidazolo[4,5-f][1,10]phenanthroline) and [η6-(C6H6)Ru(H2iiP)Cl]PF6 (Ru2; H2iiP = 2-(indole-3-yl)-imidazolo[4,5-f][1,10]phenanthroline) have been synthesized and characterized in this work. Binding properties of Ru1 and Ru2 with the triplex RNA poly(U)•poly(A)*poly(U) were investigated by spectrophotometry and spectrofluorometry as well as viscosimetry. Analysis of spectroscopic titrations and viscosity measurements show that the two complexes bind with the triplex through intercalation, while the binding affinity for Ru2 toward the triplex is stronger than that for Ru1. Melting experiments indicate that the stabilizing effects of Ru1 and Ru2 toward the triplex differ from each other. Under the conditions used herein, Ru1 only stabilizes the Hoogsteen base-paired strand (third strand) without affecting stabilization of the Watson-Crick base-paired strand (the template duplex) of the triplex, while Ru2 stabilizes both the template duplex and the third strand. Although the two complexes prefer to stabilizing the third strand rather than the template duplex, the third-strand stabilization effect of Ru2 is stronger than that of Ru1. The obtained results of this work reveal that the planarity of the intercalative ligands plays an important role in the triplex stabilization by arene Ru(II) complexes.


Asunto(s)
Poli A , Rutenio , Poli A/química , Rutenio/química , Poli U/química , ARN/química , Fenantrolinas , Conformación de Ácido Nucleico , Espectrometría de Fluorescencia
3.
J Biol Inorg Chem ; 28(5): 509-517, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37452869

RESUMEN

Two chiral ruthenium(II) polypyridyl complexes, Λ-[Ru(bpy)2(dppx)]2+ (bpy = 2,2'-bipyridine, dppx = 7,8-dimethyldipyridophenazine; Λ-1) and Δ-[Ru(bpy)2(dppx)]2+ (Δ-1) have been synthesized and characterized in this work. Interactions of Λ-1 and Δ-1 with the RNA triplex poly(U)⋅poly(A)*poly(U) have been investigated by various biophysical techniques. Spectrophotometric titrations and viscosity measurements suggested that enantiomers Λ-1 and Δ-1 bind with the triplex through intercalation, while the binding strengths of the two enantiomers toward the triplex differed only slightly from each other. Fluorescence titrations showed that although enantiomers Λ-1 and Δ-1 exhibited molecular "light switch" effects toward the triplex, the effect of Δ-1 was more marked. Furthermore, Furthermore, thermal denaturation showed that the two enantiomers have significantly different stabilizing effects on the triplex. The obtained results indicate that the racemic complex [Ru(bpy)2(dppx)]2+ is similar to a non-specific metallointercalator for the triplex investigated in this study, and chiralities of Ru(II) polypyridine complexes have an important influence on the binding and stabilizing effects of enantiomers toward the triplex. Two chiral ruthenium(II) polypyridyl complexes, Λ-[Ru(bpy)2(dppx)]2+ (bpy = 2,2'-bipyridine, dppx = 7,8-dimethyldipyridophenazine; Λ-1) and Δ-[Ru(bpy)2(dppx)]2+ (Δ-1) have been synthesized and characterized in this work. Interactions of Λ-1 and Δ-1 with the RNA triplex poly(U)⋅poly(A)*poly(U) have been investigated by various biophysical techniques. The obtained results indicate that the racemic complex [Ru(bpy)2(dppx)]2+ is similar as a non-specific metallointercalator for the triplex investigated in this study, and chiralities of Ru(II) polypyridine complexes have an important influence on the binding and stabilizing effects of enantiomers toward the triplex.


Asunto(s)
Poli A , Rutenio , Poli A/química , Rutenio/química , Poli U/química , 2,2'-Dipiridil , ARN/química
4.
Int J Biol Macromol ; 242(Pt 1): 124710, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37146854

RESUMEN

To further develop new luminescent probes for RNA, a new ruthenium(II) polypyridyl complex [Ru(dmb)2dppz-idzo]2+ (dmb = 4,4'-dimethyl-2,2'-bipyridine, dppz-idzo = dppz-imidazolone) has been synthesized and characterized in this study. Binding properties of [Ru(dmb)2dppz-idzo]2+ to RNA duplex poly(A) · poly(U) and triplex poly(U) · poly(A) ∗ poly(U) have been explored by spectroscopic techniques and viscometry experiments. The binding modes of [Ru(dmb)2dppz-idzo]2+ to RNA duplex and triplex are intercalation as revealed from spectral titrations and viscosity experiments, while the binding strength of this complex to duplex structure is significantly greater than that of triplex structure. Fluorescence titrations indicate that [Ru(dmb)2dppz-idzo]2+ can act as a molecular "light switch" for both duplex poly(A) · poly(U) and triplex poly(U) · poly(A) ∗ poly(U), while [Ru(dmb)2dppz-idzo]2+ is more sensitive to poly(A) · poly(U) compared to poly(U) · poly(A) ∗ poly(U) and poly(U). Therefore, this complex can distinguish between RNA duplex, triplex and poly(U), and can as luminescent probes for the three RNAs used in this study. In addition, thermal denaturation studies show that [Ru(dmb)2dppz-idzo]2+ is able to significantly increase the Stabilization of RNA duplex and triplex. The results obtained in this study may contribute to further understanding of the binding of Ru(II) complexes with different structural RNAs.


Asunto(s)
Rutenio , Rutenio/química , ARN/química , Poli U/química , Análisis Espectral , Poli A/química
5.
Bioorg Chem ; 135: 106523, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37027949

RESUMEN

To further explore the binding properties of Ru(Ⅱ) polypyridine complexes with RNA, three Ru(Ⅱ) complexes [Ru(phen)2(PIP)]2+ (Ru1), [Ru(phen)2(p-HPIP)]2+ (Ru2), and [Ru(phen)2(m- HPIP)]2+ (Ru3) have been synthesized and characterized in this work. The binding properties of three Ru(Ⅱ) complexes with RNA duplex poly(A)•poly(U) have been investigated by spectral and viscosity experiments. These studies all support that these three Ru(Ⅱ) complexes bind to poly RNA duplex poly(A)•poly(U) by intercalation, and Ru1 without substituents has a stronger binding affinity for poly(A)•poly(U). Interestingly, the thermal melting experiments show that these three Ru(Ⅱ) complexes all destabilize RNA duplex poly(A)•poly(U), and the destabilizing effect can be explained by the conformational changes of duplex structure induced by intercalating agents. To the best of our knowledge, this work report for the first time a small molecule capable of destabilizing an RNA duplex, which reflects that the substitution effect of intercalated ligands has an important influence on the affinity of Ru(Ⅱ) complexes to RNA duplex, and that not all Ru(Ⅱ) complexes show thermal stability effects on an RNA duplex.


Asunto(s)
Poli A , Rutenio , Poli A/química , Rutenio/farmacología , Rutenio/química , ARN/química
6.
PLoS One ; 18(3): e0282537, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36862742

RESUMEN

The spatial layout of the coastal forts defense system of the Ming Dynasty of China has been studied in a relatively comprehensive way. Nonetheless, ancient defense mechanisms have not been fully revealed. Previous studies have focused more on the macro and meso levels. Studies into its microscopic construction mechanism need to be enhanced. This research attempts to quantify and validate the rationality of the ancient microscopic defense mechanism, using the ancient defense mechanism of Pu Zhuang Suo-Fort in Zhejiang Province as an instance. This study concentrates on the distribution of firepower strength beyond the walls of coastal defense forts, as well as the effect of wall height on firepower defense capabilities. There is a specific firepower attenuation area near the walls due to the firing blind area in the coastal forts defense system. And the construction of the moat plays an additive role in its defensive capability. Meanwhile, the height of the fort wall will also affect the range of the firing blind zone under Yangmacheng. In theory, there is a reasonable height range of the wall and a proper position of the moat. This height range can meet both good economy and defensive capabilities. In turn, the position of the moats and the height of the walls can verify the rationality of the construction mechanism of the coastal forts' defense system.

7.
J Inorg Biochem ; 237: 111991, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36115329

RESUMEN

To further determine the factors that affect the binding properties of ruthenium(II) polypyridine complexes with RNA duplex and to find excellent RNA-binding agents, the binding properties of ruthenium(II) complexes [Ru(phen)2(7-OCH3-dppz)]2+ (Ru1, phen = 1,10-phenan- throline, 7-OCH3-dppz = 7-methoxy-dipyrido-[3,2-a,2',3'-c]-phenazine) and [Ru(phen)2(7-NO2- dppz)]2+ (Ru2, 7-NO2-dppz = 7-nitro-dipyrido-[3,2-a,2',3'-c]-phenazine) with RNA poly(A)•poly(U) duplex have been investigated by spectroscopic methods and viscosity measurements in this work. The results show that complexes Ru1 and Ru2 bind to poly(A)•poly(U) through intercalation and the binding affinity between Ru2 and poly(A)•poly(U) is greater than that of Ru1. Thermal denaturation experiments suggest that both ruthenium(II) complexes exhibit a significant stabilizing effect on poly(A)•poly(U) duplex. Moreover, fluorescence emission spectra exhibit that, deviating from Ru2, Ru1 exhibits a "light switch" effect for poly(A)•poly(U). This effect can be observed by the naked eye under UV light and adjusted by pH, meaning that Ru1 may act as a reversible pH controlled molecular "light switch". The results obtained in this work will contribute to our understanding of the significant influence of the intercalative ligand substituent effect in the binding process of ruthenium(II) complexes with RNA duplex.


Asunto(s)
Poli A , Rutenio , Poli A/química , Rutenio/química , Dióxido de Nitrógeno , ARN/química , Fenazinas
8.
Int J Biol Macromol ; 219: 579-586, 2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-35952809

RESUMEN

RNA triplexes have a variety of potential applications in molecular biology, diagnostics and therapeutics, while low stabilization of the third strand hinders their practical utilities under physiological conditions. In this regard, achieving the third-strand stabilization by binding small molecules is a promising strategy. Chirality is one of the basic properties of nature. To clarify achirality and chirality effects on the binding and stabilizing effects of RNA triplexes by small molecules, we report for the first time the RNA interactions of an racemic ruthenium(II) polypyridyl complex [Ru(bpy)2(11-CN-dppz)]2+ (rac-Ru1) and its two enantiomers Δ/Λ-[Ru(bpy)2(11-CN-dppz)]2+ (Δ/Λ-Ru1) with an RNA triplex poly(U-A*U) (where "-" represents Watson-Crick base pairing, and "*" denotes Hoogsteen base pairing, respectively) in this work. Research shows that although rac-Ru1 and its two enantiomers Δ/Λ-Ru1 bind to the RNA triplex through the same mode of intercalation, the binding affinity for enantiomer Δ-Ru1 is much higher than that for rac-Ru1 and enantiomer Λ-Ru1. However, compared to enantiomer Λ-Ru1, the binding affinity for rac-Ru1 does not show much of an advantage, which is slightly greater than that for the former. Thermal denaturation measurements reveal both rac-Ru1 and Δ-Ru1 to have a preference for stabilizing the third strand rather than the template duplex of the RNA triplex, while Λ-Ru1 stabilizes the RNA triplex without significant selectivity. Besides, the third-strand stabilizing effects by rac-Ru1 and Δ-Ru1 are not markedly different from each other, but more marked than that by Λ-Ru1. This work shows that the binding properties of the racemic Ru(II) polypyridyl complex with the RNA triplex are not simply an average of its two enantiomers, indicating potentially complicated binding events.


Asunto(s)
Rutenio , Conformación de Ácido Nucleico , Poli A/química , Poli U/química , ARN/química , Rutenio/química
9.
Sci Rep ; 12(1): 10773, 2022 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-35750746

RESUMEN

In ancient China, where was frequently troubled by invaders, the government set up many beacon towers for alerting and transmitting military information along the border and the coast. Many beacon sites still exist in some areas, which are generally located in dangerous places with high mountains and rough terrain, bringing great difficulties to archaeological discovery. Therefore, it is particularly important to develop a predictive model applicable to the distribution of mountain beacon sites. Taking 68 beacon sites found in Wenzhou as research samples, this study used the superimposed method of logistic regression and viewshed analysis, forming a high-precision, scientific and operational predictive model for the distribution of beacon sites, which was verified by the cross-validation method. The results showed that the beacon site predictive model simulated in this study could reduce the probability scope of site location by 90% compared with the common logistic regression predictive model, which greatly improved the accuracy and ability of site prediction. At the same time, it could also be used to understand the relationship between the known sites and their surroundings to assist in decision-making about conservation and management.


Asunto(s)
Arqueología , Sistemas de Información Geográfica , China
10.
Int J Biol Macromol ; 215: 571-578, 2022 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-35752337

RESUMEN

Binding of [Ru(phen)2ttbd]2+ (phen = 1,10-phenanthroline, ttbd = 4-(6-propenylpyrido-[3,2-a]- phenzain-10-yl-benzene-1,2-diamine) to the RNA triplex poly(U-A*U) (herein "-" and "*" refer to the Watson-Crick and Hoogsteen binding, respectively) and the duplex poly(A-U) have been investigated by spectral technology and viscosity method. Analysis of spectral titrations and viscosity experiments as well as melting measurements suggest that [Ru(phen)2ttbd]2+ binds to the studied RNA triplex and duplex through intercalation, while its binding constant toward the triplex is greater than the duplex. Luminescent titrations indicate that [Ru(phen)2ttbd]2+ can act as a molecular "light switch" for the two RNAs and the switch effect can be detected by the naked-eye. Moreover, the "light switch" can be repeatedly cycled off and on by adjusting the pH of the solution, whereas color change in the case of the triplex is more significant compared with the duplex. To our knowledge, [Ru(phen)2ttbd]2+ is the first small molecule capable of serving as a pH-controlled reversible visual molecular "light switch" for both the RNA triplex poly(U-A*U) and duplex poly(A-U). Thermal denaturation experiments suggest that [Ru(phen)2ttbd]2+ can obviously increase the triplex stabilization, while it stabilizing third-strand is more marked in comparison with the template duplex of the triplex, indicating this complex preferentially binds to third-strand. The obtained results may be useful for understanding the binding of Ru(II) polypyridyl complexes to RNAs.


Asunto(s)
Rutenio , Colorimetría , Conformación de Ácido Nucleico , Poli A/química , Poli U/química , ARN/química , Rutenio/química
11.
Front Oncol ; 12: 844477, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35494070

RESUMEN

Casein kinase 1δ/ϵ (CK1δ/ϵ) are well-established positive modulators of the Wnt/ß-catenin signaling pathway. However, the molecular mechanisms involved in the regulation of ß-catenin transcriptional activity by CK1δ/ϵ remain unclear. In this study, we found that CK1δ/ϵ could enhance ß-catenin-mediated transcription through regulating ß-catenin acetylation. CK1δ/ϵ interacted with Tip60 and facilitated the recruitment of Tip60 to ß-catenin complex, resulting in increasing ß-catenin acetylation at K49. Importantly, Tip60 significantly enhanced the SuperTopFlash reporter activity induced by CK1δ/ϵ or/and ß-catenin. Furthermore, a CK1δ/CK1ϵ/ß-catenin/Tip60 complex was detected in colon cancer cells. Simultaneous knockdown of CK1δ and CK1ϵ significantly attenuated the interaction between ß-catenin and Tip60. Notably, inhibition of CK1δ/ϵ or Tip60, with shRNA or small molecular inhibitors downregulated the level of ß-catenin acetylation at K49 in colon cancer cells. Finally, combined treatment with CK1 inhibitor SR3029 and Tip60 inhibitor MG149 had more potent inhibitory effect on ß-catenin acetylation, the transcription of Wnt target genes and the viability and proliferation in colon cancer cells. Taken together, our results revealed that the transcriptional activity of ß-catenin could be modulated by the CK1δ/ϵ-ß-catenin-Tip60 axis, which may be a potential therapeutic target for colon cancer.

12.
Int J Biol Macromol ; 209(Pt B): 1648-1655, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35489619

RESUMEN

Two Ru(II) complexes containing different substituents, [Ru(phen)2(7-CH3-dppz)]2+ (Ru1) and [Ru(phen)2(7-Br-dppz)]2+ (Ru2), have been synthesized in this study. The binding properties of Ru1 and Ru2 with the duplex RNA poly(U)•poly(A) (where "•" denotes the Watson - Crick base pairing) have been researched by biophysical techniques and viscosity measurements. Analysis of spectral titrations and viscosity measurements indicate that Ru1 and Ru2 bind to the duplex via intercalative, and the binding affinity of Ru1 with the duplex is remarkably higher than that of Ru2. Furthermore, fluorescence emission spectra demonstrates that although complexes Ru1 and Ru2 can act as molecular "light switches" for the duplex RNA, alters in fluorescence emission of Ru1 and Ru2 are prominent differences, and the effectiveness of Ru1 is more remarkable compared with that of Ru2. The melting experiments suggest that the duplex RNA stabilizing effects of Ru1 and Ru2 differ from each other, among them, complex Ru1 can obviously enhance the stability of the duplex RNA, while Ru2 has only a slightly stabilizing effect for the duplex RNA, indicating that Ru1 preferentially binds to RNA duplex over Ru2. The obtained results indicate that subtle modifications of the intercalative ligand of Ru(II) polypyridyl complex with either methyl or bromide group have a significant effect on the duplex-binding discrimination.


Asunto(s)
Complejos de Coordinación , Rutenio , Bromo , Complejos de Coordinación/química , Poli A/química , ARN/química , ARN Mensajero , Rutenio/química
13.
J Inorg Biochem ; 232: 111833, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35462128

RESUMEN

Two Ru(II) complexes, [Ru(phen)2(11-F-dppz)]2+ (Ru1, phen = 1,10-phenanthroline, 11-F-dppz = 11-fluorodipyrido[3,2-a:2',3'-c]phenazine) and [Ru(phen)2(11-CN-dppz)]2+ (Ru2, 11-CN-dppz = 11-cyanodipyrido[3,2-a:2',3'-c]phenazine), have been synthesized and characterized in this work. The binding properties of Ru1 and Ru2 with poly(A)•poly(U) RNA duplex have been investigated by spectroscopic methods and viscosity measurements. UV-vis absorption spectra and viscosity experiments demonstrate that the binding modes of Ru1 and Ru2 with poly(A)•poly(U) RNA duplex are intercalation, while the binding affinity for Ru2 is greater than that for Ru1. In addition, thermal denaturation studies reveal that both complexes significantly improve the stability of poly(A)•poly(U) duplex RNA. However, fluorescence titrations indicate that Ru1, unlike Ru2, can act as a molecular "light switch" for the poly(A)•poly(U) duplex RNA. The obtained results of this work indicate that the electron-withdrawing effect of substituents on the main ligands can significantly affect the binding of Ru(II) polypyridyl complexes with poly(A)•poly(U).


Asunto(s)
Complejos de Coordinación , Rutenio , Complejos de Coordinación/química , Fenazinas , Poli A/química , ARN/química , Rutenio/química
14.
J Inorg Biochem ; 232: 111813, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35405487

RESUMEN

To comprehend the binding properties of η6-arene Ru(II) complexes with poly(U)*poly(A)•poly(U) triplex, two arene Ru(II) complexes with different fluorine substituent positions, [(η6-C6H6)Ru(o-fpip)Cl]PF6 (Ru1,η6-C6H6 = benzene ring, o-fpip = 2-(2'­fluorine) imidazo [4,5-f] Biver et al. (2008), Gupta et al. (2012) [1, 10] phenanthroline) and [(η6-C6H6)Ru(p-fpip)Cl]PF6 (Ru2,η6-C6H6 = benzene ring, o-fpip = 2-(4'­fluorine) imidazo [4,5-f] Biver et al. (2008), Gupta et al. (2012) [1, 10] phenanthroline), have been synthesized and characterized in this study. The binding of Ru1 and Ru2 with poly(U)*poly(A)•poly(U) triplex has been investigated by viscosity measurement and spectroscopic methods. Analysis of UV-Vis absorption spectral titrations suggests that Ru1 and Ru2 bind to the triplex through an intercalative mode, but the binding affinity of Ru2 is slightly higher than that of Ru1, which is also verified by viscosity and EB (ethidium bromide) competition measurements. Furthermore, the thermal denaturation experiment shows that Ru1 and Ru2 increase the third-strand stabilization to a similar extent. Interestingly, the two complexes have essentially no effect on the stabilization of the template duplex. Considering the structure of Ru1 and Ru2, conceivably besides the intercalation of ligand, the force stabilizing the triplex should also involve covalent binding and electrostatic interaction. The obtained results will contribute to our understanding of the interaction of arene Ru(II) complexes with the poly(U)*poly(A)•poly(U) triplex.


Asunto(s)
Rutenio , Benceno , Flúor , Conformación de Ácido Nucleico , Fenantrolinas , Poli A/química , Poli U/química , ARN/química , Rutenio/química
15.
PLoS One ; 17(3): e0264238, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35275916

RESUMEN

Taking the traditional fort-type settlements in Shaanxi as the research object, quantitative research methods such as K-means clustering algorithm, correlation analysis, density analysis, and nearest neighbor index are used to study their spatial distribution, formation causes, and cluster characteristics. The objective of the study is to break through the geographical limitations of fort-type settlements research and to explore the scientific methods of classifying and analyzing traditional fort-type settlements. The conclusions are: (1) The results of cluster analysis show that the fort-type settlements in Shaanxi can be divided into three categories; (2) The overall distribution of fort-type settlements in Shaanxi shows multi-point aggregation, and contains both point and linear aggregation distribution; (3) There are four typical cluster systems among the traditional fort-type settlements in Shaanxi; (4) The factors that have the greatest influence on the distribution of settlements are construction force, wall masonry, age, fortification purpose, and topographic environment. The article innovatively proposes the "cluster system" perspective and introduces mathematical algorithms and quantitative research methods to study the cluster system of the fort-type Settlements. This approach is feasible and can be applied to other settlement-related studies. At the same time, the perspective of cluster system could be used in heritage conservation, which can contribute to the restoration of architectural relics and systemic conservation on a larger scale.


Asunto(s)
Algoritmos , Proyectos de Investigación , Análisis por Conglomerados , Correlación de Datos , Geografía
16.
J Am Med Dir Assoc ; 23(3): 405-413.e3, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35219506

RESUMEN

OBJECTIVES: A major surge in COVID-19 cases despite Singapore's high vaccination has strained the health care system in October 2021. Our aim was to assess and compare Healthcare Worker (HCW) mental well-being in 2021 against a previously published cohort in 2020. DESIGN: Cross-sectional survey study. SETTING AND PARTICIPANTS: HCWs from 4 public hospitals and a primary health care system over a 4-week duration in 2021 coinciding with a major surge compared with a similar period in 2020. METHODS: A survey comprising of the Oldenburg Burnout Inventory (OLBI), Hospital Anxiety and Depression Scale (HADS), and Safety Attitudes Questionnaire (SAQ) was distributed via email. Primary endpoints were the proportion meeting OLBI thresholds for both disengagement and exhaustion and being at risk for both Anxiety and Depression using HADS. Multivariate analysis identified significant predictors among demographic, workplace, and SAQ data. Subgroup analysis of overseas HCWs was performed. RESULTS: We surveyed 1475 HCWs. Significantly more HCWs met primary outcomes using OLBI and HADS than in 2020 (84.1% and 39.6% vs 68.2% and 23.3%, respectively; P < .001). Burnout levels were uniformly high. A HADS score ≥8 in either subscale was significantly associated with meeting burnout thresholds (P < .001). Overseas HCWs (P = .002), South Asian ethnicity (P = .004), preuniversity educational qualifications (P = .026), and longer shift workhours of 8 to <12 (P = .015) and ≥12 (P = .001) were significantly associated with meeting HADS thresholds. Among overseas HCWs (n=407), seeing family more than a year ago was significantly associated with worse OLBI disengagement scores and a greater proportion meeting HADS thresholds vs seeing them within a year or being local HCWs (47.2% vs 37.2% and 35.6%, respectively; P = .001). CONCLUSIONS AND IMPLICATIONS: HCW mental health has objectively worsened between 2020 and 2021 in the pandemic's second year. Avoiding prolonged shifts, adopting preventive mental health strategies, improving patient safety, and attention to HCWs of minority ethnicity, from overseas, and with preuniversity education may help.


Asunto(s)
COVID-19 , Salud Mental , Ansiedad/epidemiología , Ansiedad/psicología , Estudios Transversales , Depresión/psicología , Personal de Salud/psicología , Humanos , SARS-CoV-2
17.
Cell Death Dis ; 12(10): 912, 2021 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-34615853

RESUMEN

Upregulation of transmembrane protein 97 (TMEM97) has been associated with progression and poor outcome in multiple human cancers, including breast cancer. Recent studies suggest that TMEM97 may be involved in the activation of the Wnt/ß-catenin pathway. However, the molecular mechanism of TMEM97 action on Wnt/ß-catenin signaling is completely unclear. In the current study, TMEM97 was identified as an LRP6-interacting protein. TMEM97 could interact with LRP6 intracellular domain and enhance LRP6-mediated Wnt signaling in a CK1δ/ε-dependent manner. The binding of TMEM97 to LRP6 facilitated the recruitment of CK1δ/ε to LRP6 complex, resulting in LRP6 phosphorylation at Ser 1490 and the stabilization of ß-catenin. In breast cancer cells, knockout of TMEM97 attenuated the Wnt/ß-catenin signaling cascade via regulating LRP6 phosphorylation, leading to a decrease in the expression of Wnt target genes AXIN2, LEF1, and survivin. TMEM97 deficiency also suppressed cell viability, proliferation, colony formation, migration, invasion, and stemness properties in breast cancer cells. Importantly, TMEM97 knockout suppressed tumor growth through downregulating the Wnt/ß-catenin signaling pathway in a breast cancer xenograft model. Taken together, our results revealed that TMEM97 is a positive modulator of canonical Wnt signaling. TMEM97-mediated Wnt signaling is implicated in the tumorigenesis of breast cancer, and its targeted inhibition may be a promising therapeutic strategy for breast cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proteína-6 Relacionada a Receptor de Lipoproteína de Baja Densidad/metabolismo , Proteínas de la Membrana/metabolismo , Oncogenes , Vía de Señalización Wnt , Animales , Quinasa de la Caseína I/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Supervivencia Celular , Regulación hacia Abajo , Femenino , Genes Reporteros , Células HEK293 , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Fosforilación , Fosfoserina/metabolismo , Unión Proteica , Ensayo de Tumor de Célula Madre , Ensayos Antitumor por Modelo de Xenoinjerto , beta Catenina/metabolismo
18.
PLoS One ; 16(4): e0250622, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33891664

RESUMEN

In ancient China, an unobstructed, convenient and efficient transmission system nationwide was established for long-distance transmission of information. The transmission system works to different degrees in different regions, which is an important index to measure the interregional information level. Yet, some minor differences, may not be easily sensed by people subjectively. Identifying and quantifying the influences of information transmission efficiency is the best way to solve this problem. Based on the historical information map visualized by ArcGIS software, this study established a hierarchy evaluation model suitable for the analysis of ancient information transmission efficiency from three aspects of Wei-Suo system, beacon system and post system. The information transmission systems in five different regions of Wenzhou in the Ming Dynasty were quantitatively explored respectively. The results break through the qualitative conclusions of the general studies, and find out that the overall information transmission efficiency of Wenzhou in Ming Dynasty was strong in coastal, northern and southern regions, but weak in inland and central regions, which was closely related to the geographical environment and military defense demands in coastal areas of the Ming Dynasty. The model is proven to greatly contribute to judging the spatial configuration of ancient information transmission system in different regions, and provides a new idea for the study on ancient information transmission system.


Asunto(s)
Difusión de la Información/métodos , China , Historia del Siglo XV , Historia del Siglo XVI , Humanos , Difusión de la Información/historia , Programas Informáticos
19.
PLoS One ; 16(4): e0238666, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33861739

RESUMEN

The Covid-19 pandemic has placed unprecedented pressure on healthcare systems and workers around the world. Such pressures may impact on working conditions, psychological wellbeing and perception of safety. In spite of this, no study has assessed the relationship between safety attitudes and psychological outcomes. Moreover, only limited studies have examined the relationship between personal characteristics and psychological outcomes during Covid-19. From 22nd March 2020 to 18th June 2020, healthcare workers from the United Kingdom, Poland, and Singapore were invited to participate using a self-administered questionnaire comprising the Safety Attitudes Questionnaire (SAQ), Oldenburg Burnout Inventory (OLBI) and Hospital Anxiety and Depression Scale (HADS) to evaluate safety culture, burnout and anxiety/depression. Multivariate logistic regression was used to determine predictors of burnout, anxiety and depression. Of 3,537 healthcare workers who participated in the study, 2,364 (67%) screened positive for burnout, 701 (20%) for anxiety, and 389 (11%) for depression. Significant predictors of burnout included patient-facing roles: doctor (OR 2.10; 95% CI 1.49-2.95), nurse (OR 1.38; 95% CI 1.04-1.84), and 'other clinical' (OR 2.02; 95% CI 1.45-2.82); being redeployed (OR 1.27; 95% CI 1.02-1.58), bottom quartile SAQ score (OR 2.43; 95% CI 1.98-2.99), anxiety (OR 4.87; 95% CI 3.92-6.06) and depression (OR 4.06; 95% CI 3.04-5.42). Significant factors inversely correlated with burnout included being tested for SARS-CoV-2 (OR 0.64; 95% CI 0.51-0.82) and top quartile SAQ score (OR 0.30; 95% CI 0.22-0.40). Significant factors associated with anxiety and depression, included burnout, gender, safety attitudes and job role. Our findings demonstrate a significant burden of burnout, anxiety, and depression amongst healthcare workers. A strong association was seen between SARS-CoV-2 testing, safety attitudes, gender, job role, redeployment and psychological state. These findings highlight the importance of targeted support services for at risk groups and proactive SARS-CoV-2 testing of healthcare workers.


Asunto(s)
Agotamiento Profesional/psicología , COVID-19/psicología , Personal de Salud/psicología , Adulto , Ansiedad/psicología , Agotamiento Profesional/etiología , Agotamiento Psicológico/psicología , COVID-19/epidemiología , Estudios Transversales , Depresión/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estrés Laboral/psicología , Pandemias , Polonia/epidemiología , SARS-CoV-2/aislamiento & purificación , Singapur/epidemiología , Encuestas y Cuestionarios , Reino Unido/epidemiología
20.
J Inorg Biochem ; 214: 111301, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33166867

RESUMEN

Two chiral Ru(II) polypyridyl complexes, Δ-[Ru(bpy)2(6-F-dppz)]2+ (Δ-1; bpy = 2,2'-bipyridine, 6-F-dppz = 6-fluorodipyrido[3,2-a:2',3'-c]phenazine) and Λ-[Ru(bpy)2(6-F-dppz)]2+ (Λ-1), have been synthesized and characterized as binders for the RNA poly(U)•poly(A)*poly(U) triplex and poly(A)•poly(U) duplex in this work. Analysis of the UV-Vis absorption spectra and fluorescence emission spectra indicates that the binding of intercalating Δ-1 with the triplex and duplex RNA is greater than that of Λ-1, while the binding affinities of the two enantiomers to triplex structure is stronger than that of duplex structure. Fluorescence titrations show that the two enantiomers can act as molecular "light switches" for triple- and double-helical RNA. Thermal denaturation studies revealed that that the two enantiomers are more stable to Watson-Crick base-paired double strand of the triplex than the Hoogsteen base-paired third strand, but their stability and selectivity are different. For Δ-enantiomer, the increase of the thermal stability of the Watson-Crick base-paired duplex (13 °C) is slightly stronger than of the Hoogsteen base-paired strand (10 °C), displaying no obvious selectivity. However, compared to the Hoogsteen base-paired strand (5 °C), the stability of the Λ-enantiomer to the Watson-Crick base-paired duplex (13 °C) is more significant, which has obvious selectivity. The overall increase in viscosity of the RNA-(Λ-1) system and its curve shape are similar to that of the RNA-(Δ-1) system, suggesting that the binding modes of two enantiomers with RNA are intercalation. The obtained results in this work may be useful for understanding the binding differences in chiral Ru(II) polypyridyl complexes toward RNA triplex and duplex.


Asunto(s)
Complejos de Coordinación/química , ARN Bicatenario/química , Rutenio/química
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