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1.
Angew Chem Int Ed Engl ; 62(29): e202305942, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37150744

RESUMO

Glassy and liquid state metal-organic frameworks (MOFs) are emerging type of materials subjected to intense research for their rich physical and chemical properties. In this report, we obtained the first glassy MOF that involves metal-carboxylate cluster building units via multi-stage structural transformations. This MOF is composed of linear [Mn3 (COO)6 ] node and flexible pyridyl-ethenylbenzoic linker. The crystalline MOF was first perturbed by vapor hydration and thermal dehydration to give an amorphous state, which can go through a glass transition at 505 K into a super-cooled liquid. The super-cooled liquid state is stable through a wide temperature range of 40 K and has the largest fragility index of 105, giving a broad processing window. Remarkably, the super-cooled liquid can not only be quenched into glass, but also recrystallize into the initial MOF when heated to a higher temperature above 558 K. The mechanism of the multi-stage structural transformations was studied by systematic characterizations of in situ X-ray diffraction, calorimetry, rheological, spectroscopic and pair-distribution function analysis. These multi-stage transformations not only represent a rare example of high temperature coordinative recognition and self-assembly, but also provide new MOF processing strategy through crystal-amorphous-liquid-crystal transformations.

2.
Nano Lett ; 23(9): 4066-4073, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37097764

RESUMO

Reticular chemistry provides opportunities to design solid-state electrolytes (SSEs) with modular tunability. However, SSEs based on modularly designed crystalline metal-organic frameworks (MOFs) often require liquid electrolytes for interfacial contact. Monolithic glassy MOFs can have liquid processability and uniform lithium conduction, which is promising for the reticular design of SSE without liquid electrolytes. Here, we develop a generalizable strategy for the modular design of noncrystalline SSEs based on a bottom-up synthesis of glassy MOFs. We demonstrate such a strategy by linking polyethylene glycol (PEG) struts and nanosized titanium-oxo clusters into network structures termed titanium alkoxide networks (TANs). The modular design allows the incorporation of PEG linkers with different molecular weights, which give optimal chain flexibility for high ionic conductivity, and the reticular coordinative network provides a controlled degree of cross-linking that gives adequate mechanical strength. This research shows the power of reticular design in noncrystalline molecular framework materials for SSEs.

3.
PeerJ ; 10: e13708, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35846880

RESUMO

Background: Triple-negative breast cancer (TNBC) is the most malignant subtype of breast cancer and lacks effective biomarkers. This study seeks to unravel the expression status and the prospective transcriptional mechanisms of EZH1/EZH2 in TNBC tissue samples. Moreover, another objective of this study is to reveal the prognostic molecular signatures for risk stratification in TNBC patients. Methods: To determine the expression status of EZH1/EZH2 in TNBC tissue samples, microarray analysis and immunohistochemistry were performed on in house breast cancer tissue samples. External mRNA expression matrices were used to verify its expression patterns. Furthermore, the prospective transcriptional mechanisms of EZH1/EZH2 in TNBC were explored by performing differential expression analysis, co-expression analysis, and chromatin immunoprecipitation sequencing analysis. Kaplan-Meier survival analysis and univariate Cox regression analysis were utilized to detect the prognostic molecular signatures in TNBC patients. Nomogram and time-dependent receiver operating characteristic curves were plotted to predict the risk stratification ability of the prognostic-signatures-based Cox model. Results: In-house TMAs (66 TNBC vs. 106 non-TNBC) and external gene microarrays, as well as RNA-seq datasets (1,135 TNBC vs. 6,198 non-TNBC) results, confirmed the downregulation of EZH1 at both the protein and mRNA levels (SMD = -0.59 [-0.80, -0.37]), as is opposite to that of EZH2 (SMD = 0.74 [0.40, 1.08]). The upregulated transcriptional target genes of EZH1 were significantly aggregated in the cell cycle pathway, where CCNA2, CCNB1, MAD2L1, and PKMYT1 were determined as key transcriptional targets. Additionally, the downregulated transcriptional targets of EZH2 were enriched in response to the hormone, where ESR1 was identified as the hub gene. The six-signature-based prognostic model produced an impressive performance in this study, with a training AUC of 0.753, 0.981, and 0.977 at 3-, 5-, and 10-year survival probability, respectively. Conclusion: EZH1 downregulation may be a key modulator in the progression of TNBC through negative transcriptional regulation by targeting CCNA2, CCNB1, MAD2L1, and PKMYT1.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Proteínas de Ciclo Celular/genética , Regulação para Baixo/genética , Proteínas de Membrana/genética , Prognóstico , Estudos Prospectivos , Proteínas Serina-Treonina Quinases/genética , Proteínas Tirosina Quinases/genética , RNA Mensageiro , Neoplasias de Mama Triplo Negativas/genética
4.
J Am Chem Soc ; 144(29): 13021-13025, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35748600

RESUMO

Metal-organic framework (MOF) glasses are a fascinating new class of materials, yet their prosperity has been impeded by the scarcity of known examples and limited vitrification methods. In the work described in this report, we applied synergistic stimuli of vapor hydration and thermal dehydration to introduce structural disorders in interpenetrated dia-net MOF, which facilitate the formation of stable super-cooled liquid and quenched glass. The material after stimulus has a glass transition temperature (Tg) of 560 K, far below the decomposition temperature of 695 K. When heated, the perturbed MOF enters a super-cooled liquid phase that is stable for a long period of time (>104 s), across a broad temperature range (26 K), and has a large fragility index of 83. Quenching the super-cooled liquid gives rise to porous MOF glass with maintained framework connectivity, confirmed by EXAFS and PDF analysis. This method provides a fundamentally new route to obtain glassy materials from MOFs that cannot be melted without causing decomposition.

5.
Head Face Med ; 17(1): 9, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33741006

RESUMO

BACKGROUND: 3D facial scanning has changed the way facial aesthetic is evaluated and has numerous advantages for facial analysis. The specific relationship between lip vermilion morphological changes after orthodontic extraction treatment has not been fully explained. The objective of this study was to evaluate 3D morphological changes after orthodontic extraction treatment in lip vermilion of adult females with dentoalveolar protrusion using a structured light-based scanner. METHODS: Forty-two female subjects (25.2 ± 1.9 years) were recruited as the treatment group; these patients had undergone extraction treatment and achieved better sagittal profiles. Twenty female subjects (25.5 ± 2.1 years) were enrolled in the non-treatment group; these patients did not require any orthodontic treatment. The follow up time for the treatment group was more than 24 months and for the non-treatment group was more than 12 months. 3D facial scans were captured using 3D CaMega. Six landmarks (Ls, Li, R.Chp, L.Chp, R.Ch, and L.Ch), three linear measurements (mouth height, philtrum width, and mouth width), and three area measurements (upper, lower, and total vermilion area) were measured. The spatial deviations of three volumetric measurements (upper, lower, and total vermilion) were constructed for quantitative analysis. Color-coded displacement map were constructed for visualization of the soft-tissue displacement as qualitative evaluation. RESULTS: Mouth height and philtrum width decreased (-0.93 mm and - 1.08 mm, respectively) significantly (p = 0.008 and p = 0.027, respectively), and no significant (p = 0.488) change in mouth width was observed in the treatment group. The lower and total vermilion surface areas decreased (-51.00mm2 and - 69.82mm2, respectively) significantly (p = 0.003 and p = 0.031, respectively) in the treatment group, but no statistically significant (p = 0.752) change was detected in the upper vermilion. In the treatment group, significant retractions were observed in the color-coded displacement map, and three volumetric measurements of vermilion changed significantly (p = 0.012, p = 0.001 and p = 0.004, respectively). Significant differences were found between the treatment group and the non-treatment group in the linear, area and volumetric measurements. CONCLUSIONS: This study established a method for qualitative and quantitative evaluation of the lip vermilion. Significant 3D retraction of the lip vermilion after the extraction treatment was found, with morphological variation between upper and lower vermilion.


Assuntos
Face , Lábio , Adulto , Cefalometria , Feminino , Humanos , Lábio/anatomia & histologia , Lábio/diagnóstico por imagem , Estudos Longitudinais , Estudos Retrospectivos
6.
Biotechnol Appl Biochem ; 65(4): 533-539, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29274173

RESUMO

Interstitial cells of Cajal (ICC), especially myenteric interstitial cells of Cajal (ICC-MY), are key to gastrointestinal motility. However, their role in the pathogenesis of functional dyspepsia (FD) is unclear. Therefore, autophagy and differentiation of ICC-MY were investigated to elucidate the pathogenesis of gastric motility disorder in FD. FD model was induced by chronic stress via tail clamping in rats, which was assessed by the vital signs of rats, gastric emptying rate result, and histology. The ultrastructure of ICC-MY was examined using transmission electron microscope. In ICC-MY, changes in autophagic biomarkers (Beclin1 and LC3B) and differentiation biomarkers (c-kit and SCF) were evaluated with in situ hybridization, quantitative real time PCR, immunofluorescence, and Western blot, respectively. The FD model was successfully induced in rats, as evidenced by the abnormal vital signs (such as loss of appetite, liquid excreta, less activity, and slower weight gain), the decrease in gastric emptying rates, and little pathological change in gastric antrum tissue. Compared with the control group, FD caused increased organelle denaturation or reduction and increase in vacuolization. FD also promoted generation of autophagosomes in ICC-MY. Moreover, increased the expression of Beclin1 and LC3B, but decreased expression of c-kit and SCF. Excessive autophagy and abnormal differentiation of ICC-MY may contribute to the pathogenesis of gastric motility disorder in FD.


Assuntos
Autofagia , Dispepsia/patologia , Gastroparesia/patologia , Células Intersticiais de Cajal/patologia , Animais , Diferenciação Celular , Dispepsia/metabolismo , Feminino , Motilidade Gastrointestinal , Gastroparesia/metabolismo , Células Intersticiais de Cajal/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
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