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1.
Angew Chem Int Ed Engl ; 62(52): e202311451, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37861089

RESUMO

Unlike absorption-based colors of dyes and pigments, reflection-based colors of photonic crystals, so called "structural colors", are responsive to external stimuli, but can remain unfaded for over ten million years, and therefore regarded as a next-generation coloring mechanism. However, it is a challenge to rationally design the spectra of structural colors, where one structure gives only one reflection peak defined by Bragg's law, unlike those of absorption-based colors. Here, we report a reconfigurable photonic crystal that exhibits single-peak and double-peak structural colors. This photonic crystal is composed of a colloidal nanosheet in water, which spontaneously adopts a layered structure with single periodicity (407 nm). After a temperature-gradient treatment, the photonic crystal segregates into two regions with shrunken (385 nm) and expanded (448 nm) periodicities, and thus exhibits double reflection peaks that are blue- and red-shifted from the original one, respectively. Notably, the transition between the single-peak and double-peak states is reversible.

2.
Ann Transl Med ; 9(8): 627, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33987325

RESUMO

BACKGROUND: Proliferation of vascular smooth muscle cells (VSMCs) plays a vital role in the progression of vascular remodeling and hypertension. Apelin-13 promotes VSMC proliferation of normal rats. This study was designed to investigate the roles of apelin receptor (APJ) and apelin-13 in VSMC proliferation of hypertension rats and underlying mechanisms. METHODS: Primary VSMCs were obtained from aorta of Wistar-Kyoto rat (WKY) and spontaneously hypertensive rat (SHR). The expressions of apelin and APJ were detected by Western bolt and PCR, as well as immunohistochemistry. VSMC proliferation was evaluated with CCK-8 kit, PCNA protein expression and percentage of EdU-positive cells. Autophagy was determined by the ratio of LC3BII to LC3BI, ATG5 and p62 protein expressions, as well as LC3B immunofluorescence. RESULTS: APJ expression was increased while apelin expression was reduced in aorta and VSMCs of SHR compared with those of WKY. Exogenous apelin-13 promoted VSMC proliferation and autophagy of both WKY and SHR, which were prevented by APJ antagonist F13A. Blockade of APJ had no significant effects on VSMC proliferation and autophagy of WKY, but attenuated VSMC proliferation and autophagy of SHR. Administration of autophagy inhibitor 3-methyladenine (3-MA) not only attenuated VSMC proliferation of SHR, but prevented apelin-13-induced VSMC proliferation of both WKY and SHR. CONCLUSIONS: Apelin-13 stimulates VSMC proliferation via APJ-mediated enhancement in autophagy. APJ upregulation in SHR contributes to the enhanced VSMC proliferation.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31440212

RESUMO

Background: Although many studies indicate a positive correlation between GHRL gene Leu72Met polymorphism and an increased susceptibility to type 2 diabetes mellitus (T2DM), inconsistencies between independent studies still remain. Objective: Considering the inconsistencies between them, we have performed the current meta-analysis study. The objective of this study is to better examine the correlation of the GHRL gene Leu72Met polymorphism and T2DM. Methods: The current meta-analysis, involving 8,194 participants from 11 independent studies, was performed. A fixed effect model was used to evaluate the pooled odds ratios (ORs) and the corresponding 95% confidence intervals (95% CIs). Results: A significant association was found between T2DM and GHRL gene Leu72Met polymorphism under recessive (OR: 1.33, 95% CI: 1.01-1.76, P = 0.04), and homozygous genetic models (OR: 1.34, 95% CI: 1.01-1.78, P = 0.04) in the whole population. The correlation was more distinct in our subgroup analysis of the Chinese population under recessive (OR: 1.52, 95% CI: 1.07-2.15, P = 0.02), dominant (OR: 1.70, 95% CI: 1.38-2.10, P < 0.00001), additive (OR: 1.16, 95% CI: 1.02-1.33, P = 0.02), and homozygous genetic models (OR: 1.54, 95% CI: 1.07-2.20, P = 0.02). Conclusions: In short, GHRL gene Leu72Met polymorphism was significantly correlated with increased T2DM risk, particularly in the Chinese population. Individuals carrying the Met72 allele of GHRL Leu72Met gene polymorphism, particularly those of Chinese ancestry, may be more susceptible to developing T2DM disease.

4.
Nat Commun ; 10(1): 1440, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30926927

RESUMO

Separation of a homogeneous mixture of different components to reach an ordered out-of-equilibrium state in solution has attracted continuous attention. While this can be achieved using external chemical fuels or photo energy, an alternative energy source is heat. Here we realize a temperature-controlled cycle of transitions between ordered and disordered states based on a mixture of two kinds of building blocks that self-assemble into cubic structures (nanocubes). An almost statistical mixture of nanocubes (disordered state) is thermodynamically most stable at lower temperature (25 °C), while homoleptic assemblies composed of single components are preferentially produced at higher temperature (100 °C) followed by rapid cooling. The scrambling of the building blocks between the nanocubes takes place through the exchange of free building blocks dissociated from the nanocubes. Based on this mechanism, it is possible to accelerate, retard, and perfectly block the scrambling by the guest molecules encapsulated in the nanocubes.

5.
Nat Commun ; 9(1): 4530, 2018 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-30382098

RESUMO

Induced-fit or conformational selection is of profound significance in biological regulation. Biological receptors alter their conformation to respond to the shape and electrostatic surfaces of guest molecules. Here we report a water-soluble artificial molecular host that can sensitively respond to the size, shape, and charged state of guest molecules. The molecular host, i.e. nanocube, is an assembled structure consisting of six gear-shaped amphiphiles (GSAs). This nanocube can expand or contract its size upon the encapsulation of neutral and anionic guest molecules with a volume ranging from 74 to 535 Å3 by induced-fit. The responding property of this nanocube, reminiscent of a feature of biological molecules, arises from the fact that the GSAs in the nanocubes are connected to each other only through the hydrophobic effect and very weak intermolecular interactions such as van der Waals and cation-π interactions.

6.
Artigo em Inglês | MEDLINE | ID: mdl-29875737

RESUMO

BACKGROUND: Although solute carrier family 30 (zinc transporter) member 8 (SLC30A8) gene 807C/T polymorphism is associated with an increased risk of type 2 diabetes mellitus (T2DM) risk, there remains some inconsistency between individual studies. OBJECTIVE: The aim of the study is to explore the relationship between SLC30A8 gene 807C/T polymorphism and T2DM in the Chinese population. METHODS: The current meta-analysis compiles and analyzes the data of 6,942 participants from 10 independent studies. Either a fixed or random-effects model was adopted to evaluate the pooled odds ratio (ORs) and the corresponding 95% confidence interval (95% CI). RESULTS: A significant association between SLC30A8 gene 807C/T polymorphism and T2DM was found in the Chinese population under allelic (OR: 0.85, 95% CI: 0.80-0.91, P = 7.42 × 10-7), recessive (OR: 0.52, 95% CI: 0.38-0.72, P = 8.49 × 10-5), dominant (OR: 2.40, 95% CI: 1.68-3.41, P = 1.30 × 10-6), homozygous (OR: 0.52, 95% CI: 0.40-0.67, P = 2.90 × 10-7), heterozygous (OR: 0.79, 95% CI: 0.71-0.88, P = 1.63 × 10-5), and additive genetic models (OR: 0.73, 95% CI: 0.64-0.83, P = 7.05 × 10-7). CONCLUSION: SLC30A8 gene 807C/T polymorphism was significantly associated with an increased T2DM risk in the Chinese population. Therefore, individuals of Chinese descent with the C allele of SLC30A8 gene 807C/T polymorphism may be more susceptible to developing T2DM, while individuals with the T allele may be protected against T2DM.

7.
Chemistry ; 24(37): 9274-9284, 2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29714039

RESUMO

Spontaneous formation of the heteroleptic cadmium(II) bis(terpyridine) complex under ambient conditions can be achieved by a combination of 6,6''-di(2,6-dimethoxylphenyl)-substituted and unsubstituted terpyridine-based ligands. Building on this dynamic heteroleptic complexation, diverse metallo-supramolecular macrocycles and cages were readily assembled in quantitative yields from the predesigned multicomponent systems. The complementary ligation reinforced self-recognition to facilitate the shape-dependent self-sorting of a four-component dynamic library into two well-defined parallelograms. In addition, the subtle lability difference between homoleptic and heteroleptic complexes led to the site-selective CdII -ZnII transmetalation in the Sierpinski triangle. Facile construction of a dodecanuclear tetrahedral metallocage was also realized by using two self-recognizable tritopic building blocks. The photophysical study of the metallo-supramolecules assembled from the d10 metal ions revealed intense ligand-based photoluminescence in solution. The self-assembly strategy described here provides an efficient methodology for building pre-programmable, sophisticated supramolecular architectures furnished with photoactivity.

8.
Chemistry ; 24(36): 9130-9135, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29663544

RESUMO

A thermally highly stable molecular self-assembly (nanocube) in water, the decomposition temperature of which is 415 K, was developed by designing a gear-shaped amphiphile (GSA) with an indented hydrophobic surface, even though the nanocube is stabilized only by van der Waals (vdW) and cation-π interactions as well as the hydrophobic effect. The introduction of an electron-donating substituent in one of the benzene rings of the GSA increased the decomposition temperature by 12 K, which is due to the stronger cation-π interactions between the benzene ring and positively charged pyridinium rings and tighter molecular meshing between the GSAs in the nanocube. The position of the substituent introduced in the benzene ring greatly affects the thermal stability of the nanocubes, and this indicates that both vdW (molecular meshing) and cation-π interactions are crucial for improving the thermal stability of the hydrophobic assemblies.

9.
J Org Chem ; 83(9): 5132-5137, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29644858

RESUMO

The effect of the methyl groups in neutral gear-shaped amphiphiles (GSAs) on the stability of nanocubes was investigated using a novel C2 v-symmetric GSA, which was synthesized using selective alternate trilithiation of a pentabrominated hexaphenylbenzene derivative. The lack of only one methyl group in the GSA decreased the association constant for the assembly of the nanocube by 3 orders of magnitude. A surface analysis recently developed by the authors (SAVPR: surface analysis with varying probe radii) was carried out for characteristic isomers of the nanocube consisting of C2 v-symmetric GSAs. It was found that the methyl groups near the equator of the nanocube play a significant role in the stabilization of the nanocubes.

10.
Chem Commun (Camb) ; 54(27): 3335-3338, 2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29437180

RESUMO

A novel method for the semi-quantitative evaluation of molecular meshing in molecular complexes and assemblies (SAVPR: surface analysis with varying probe radii) is proposed. SAVPR revealed that the extremely high stability of hexameric assemblies (nanocubes) is due to tight molecular meshing between the components in the assemblies, indicating the importance of van der Waals interactions in hydrophobic molecular assemblies.

11.
Biomed Rep ; 2(5): 699-708, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25054014

RESUMO

The methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism has been suggested to be associated with the risk of essential hypertension (EH), however, results remain inconclusive. To investigate this association, the present meta-analysis of 27 studies including 5,418 cases and 4,997 controls was performed. The pooled odds ratio (OR) and its corresponding 95% confidence interval were calculated using the random-effects model. A significant association between the MTHFR C677T gene polymorphism and EH was found under the allelic (OR, 1.32; 95% CI, 1.20-1.45; P=0.000), dominant (OR, 1.39; 95% CI, 1.25-1.55; P=0.000), recessive (OR, 1.38; 95% CI, 1.18-1.62; P=0.000), homozygote (OR, 1.59; 95% CI, 1.32-1.92; P=0.000), and heterozygote (OR, 1.32; 95% CI, 1.20-1.45; P=0.000) genetic models. A strong association was also revealed in subgroups, including Asian, Caucasian and Chinese. The Japanese subgroup did not show any significant association under all models. Meta-regression analyses suggested that the study design was a potential source of heterogeneity, whereas the subgroup analysis additionally indicated that the population origin may also be an explanation. Another subgroup analysis revealed that hospital-based studies have a stronger association than population-based studies, however, the former suffered a greater heterogeneity. Funnel plot and Egger's test manifested no evidence of publication bias. In conclusion, the present study supports the evidence for the association between the MTHFR C677T gene polymorphism and EH in the whole population, as well as in subgroups, such as Asian, Caucasian and Chinese. The carriers of the 677T allele are susceptible to EH.

12.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 24(6): 703-5, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18067089

RESUMO

OBJECTIVE: To investigate the association of thiazide-sensitive Na+ -Cl* cotransporter (TSC) gene 1784C/T and 2736G/A polymorphisms with the risk of essential hypertension (EH) in a Han nationality population. METHODS: A community-based, case-control study including 190 EH patients and 94 sex- and age-matched controls was conducted. Genotypes of TSC gene 1784C/T and 2736G/A polymorphisms were analyzed by gene chip technology. RESULTS: The genotype (1784C/T CC, CT, TT:87, 88, 15 vs 36, 52, 6û2736G/A GG, AG, AA:167, 22, 1 vs 83, 10, 1) and alleles frequency (1784C/T C, T:68.9%, 31.1% vs 66.0%, 34.0%; 2736G/A G,A:93.7%, 6.3% vs 93.6%, 6.4%) distribution of 1784C/T and 2736G/A showed no significant difference between the EH group and the control group (P >0.05). Moreover, no significant difference was observed in the frequencies distribution of four haplotypes (P > 0.05); Logistic regression analysis of haplotypes showed that the risk of EH had no significant difference in the population with different haplotypes (P > 0.05). CONCLUSION: The 1784C/T and 2736G/A polymorphisms of TSC gene may not play an important role in the etiology of EH in a Han nationality population. The studies in the future are warranted to validate our findings.


Assuntos
Frequência do Gene , Hipertensão/genética , Receptores de Droga/genética , Simportadores de Cloreto de Sódio/genética , Feminino , Predisposição Genética para Doença , Haplótipos , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Risco
13.
Chin Med J (Engl) ; 120(9): 782-6, 2007 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-17531119

RESUMO

BACKGROUND: The renin-angiotensin-aldosterone system (RAAS) is important for the development of essential hypertension, and many antihypertensive drugs target it. This study was undertaken to determine whether polymorphisms in the renin-angiotensin-aldosterone system are related to the blood pressure (BP) response to diuretic treatment in a Chinese Han ethnic population. METHODS: Fifty-four patients with essential hypertension received hydrochlorothiazide (12.5 mg, once daily) as monotherapy for four weeks. Seven polymorphisms in RAAS genes were genotyped by gene chip technology. The relationship between these polymorphisms and the change in blood pressure was observed after the 4-week treatment. RESULTS: The patients with angiotensinogen (AGT) -6G allele showed a greater reduction in diastolic BP (P=0.025) and mean BP (P=0.039) than those carrying AA genotype. Patients carrying aldosterone synthase (CYP11B2) CC genotype exhibited a greater BP reduction than those carrying CT and TT genotypes (systolic BP: P=0.030; diastolic BP: P=0.026; mean BP: P=0.003). In addition, patients with a combination of CYP11B2 CC genotype and angiotensin converting enzyme (ACE) D allele might have a more pronounced reduction of systolic BP than those with any other genotypic combinations of the two genes (P=0.007). CONCLUSIONS: AGT-6G allele, CYP11B2 -344CC genotype and its combination with ACE D allele are associated with BP response to hydrochlorothiazide treatment. Larger studies are warranted to validate this finding.


Assuntos
Angiotensinogênio/genética , Citocromo P-450 CYP11B2/genética , Hidroclorotiazida/uso terapêutico , Hipertensão/tratamento farmacológico , Hipertensão/genética , Peptidil Dipeptidase A/genética , Idoso , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único
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