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1.
Nat Commun ; 15(1): 2920, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575569

RESUMO

Metal-organic frameworks (MOFs) with diverse chemistry, structures, and properties have emerged as appealing materials for miniaturized solid-state devices. The incorporation of MOF films in these devices, such as the integrated microelectronics and nanophotonics, requires robust patterning methods. However, existing MOF patterning methods suffer from some combinations of limited material adaptability, compromised patterning resolution and scalability, and degraded properties. Here we report a universal, crosslinking-induced patterning approach for various MOFs, termed as CLIP-MOF. Via resist-free, direct photo- and electron-beam (e-beam) lithography, the ligand crosslinking chemistry leads to drastically reduced solubility of colloidal MOFs, permitting selective removal of unexposed MOF films with developer solvents. This enables scalable, micro-/nanoscale (≈70 nm resolution), and multimaterial patterning of MOFs on large-area, rigid or flexible substrates. Patterned MOF films preserve their crystallinity, porosity, and other properties tailored for targeted applications, such as diffractive gas sensors and electrochromic pixels. The combined features of CLIP-MOF create more possibilities in the system-level integration of MOFs in various electronic, photonic, and biomedical devices.

2.
Nutr. hosp ; 41(1): 130-137, Ene-Feb, 2024. tab, graf
Artigo em Inglês | IBECS | ID: ibc-230892

RESUMO

Objective: to evaluate leptin levels and its relation to nutritional status in Crohn’s disease (CD).Methods: the study included 154 CD patients and healthy controls. Leptin level was determined before treatment. Nutrition levels were assessedusing the Nutrition Risk Screening 2002 (NRS-2002) and Patient-Generated Subjective Global Assessment (PG-SGA). Indicators included bodymass index (BMI), mid-arm circumference, the circumference of the upper-arm muscle, triceps skinfold thickness, and circumference of legs.Results: leptin levels differed between CD patients (1,025 ± 874 ng/ml) and controls (18,48 ± 1,222 ng/ml). Significant differences were seenin NRS-2002, PG-SGA scores, BMI and other nutritional indicators. Negative correlations were observed between leptin and NRS-2002, PG-SGAscores, while positive correlations were observed with other nutritional indicators. The receiver operating characteristic (ROC) curve showedassociation between leptin and the diagnosis of CD, suggesting leptin concentration below 803.02 ng/ml as a threshold for CD.Conclusion: dysfunctional leptin regulation may relate to poor nutritional status associated with CD. The leptin level is thus an additional toolfor evaluating CD patients, predicting disease activity and clinical response. Leptin may be a potential target for intervention in CD to improvenutritional status.(AU)


Objetivo: evaluar los niveles de leptina y su relación con el estado nutricional en la enfermedad de Crohn (EC).Métodos: se incluyeron 154 pacientes con EC y controles sanos. El nivel de leptina se determinó antes del tratamiento. La situación nutricionalse evaluó mediante el examen de riesgo nutricional 2002 (NRS-2002) y la Valoración Global Subjetiva Generada por el Paciente (VGS-GP). Losindicadores incluyen el índice de masa corporal (IMC), la circunferencia media del brazo, la circunferencia del músculo superior del brazo, elgrosor del pliegue cutáneo del tríceps y la circunferencia de las piernas.Resultados: los niveles de leptina difirieron entre los pacientes con EC (1.025 ± 874 ng/ml) y los controles (18.48 ± 1.222 ng/ml). Se obser-varon diferencias significativas en NRS-2002, puntajes de VGS-GP, IMC y otros indicadores nutricionales. Se observaron correlaciones negativasentre leptina y NRS-2002, puntuaciones de VGS-GP, mientras que se observaron correlaciones positivas con otros indicadores nutricionales.La curva ROC mostró asociación entre leptina y el diagnóstico de EC, sugiriendo concentraciones de leptina por debajo de 803,02 ng/ml comoumbral para EC.Conclusión: puede relacionarse la alteración en la regulación de la leptina con la peor situación nutricional en enfermos con EC. La leptinapuede ser un objetivo potencial para la intervención en EC a fin de mejorar el estado nutricional.(AU)


Assuntos
Humanos , Masculino , Feminino , Doença de Crohn , Leptina , Estado Nutricional , Avaliação Nutricional , Índice de Massa Corporal , Ciências da Nutrição , Estudos de Casos e Controles
3.
ACS Nano ; 18(9): 6896-6907, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38376996

RESUMO

Microscale patterning of colloidal perovskite nanocrystals (NCs) is essential for their integration in advanced device platforms, such as high-definition displays. However, perovskite NCs usually show degraded optical and/or electrical properties after patterning with existing approaches, posing a critical challenge for their optoelectronic applications. Here we achieve nondestructive, direct optical patterning of perovskite NCs with rationally designed carbene-based cross-linkers and demonstrate their applications in high-performance light-emitting diodes. We reveal that both the photochemical properties and the electronic structures of cross-linkers need to be carefully tailored to the material properties of perovskite NCs. This method produces high-resolution (∼4000 ppi) NC patterns with preserved photoluminescent quantum efficiencies and charge transport properties. Prototype light-emitting diodes with patterned/cross-linked NC layers show a maximum luminance of over 60000 cd m-2 and a peak external quantum efficiency of 16%, among the highest for patterned perovskite electroluminescent devices. Such a material-adapted patterning method enabled by designs from a photochemistry perspective could foster the applications of perovskite NCs in system-level electronic and optoelectronic devices.

4.
Lab Chip ; 24(5): 1307-1326, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38247405

RESUMO

High-throughput microfluidic systems are widely used in biomedical fields for tasks like disease detection, drug testing, and material discovery. Despite the great advances in automation and throughput, the large amounts of data generated by the high-throughput microfluidic systems generally outpace the abilities of manual analysis. Recently, the convergence of microfluidic systems and artificial intelligence (AI) has been promising in solving the issue by significantly accelerating the process of data analysis as well as improving the capability of intelligent decision. This review offers a comprehensive introduction on AI methods and outlines the current advances of high-throughput microfluidic systems accelerated by AI, covering biomedical detection, drug screening, and automated system control and design. Furthermore, the challenges and opportunities in this field are critically discussed as well.


Assuntos
Inteligência Artificial , Microfluídica , Automação , Avaliação Pré-Clínica de Medicamentos
5.
Entropy (Basel) ; 26(1)2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38248178

RESUMO

In this paper, a unified gas kinetic particle (UGKP) method is developed for radiative transfer in both absorbing and anisotropic scattering media. This numerical method is constructed based on our theoretical work on the model reduction for an anisotropic scattering system. The macroscopic solver of this method directly solves the macroscopic anisotropic diffusion equations, eliminating the need to solve higher-order moment equations. The reconstruction of macroscopic scattering source in the microscopic solver, based on the multiscale equivalent phase function we proposed in this work, has also been simplified as one single scattering process, significantly reducing the computational costs. The proposed method has also the property of asymptotic preserving. In the optically thick regime, the proposed method solves the diffusion limit equations for an anisotropic system. In the optically thin regime, the kinetic processes of photon transport are simulated. The consistency and efficiency of the proposed method have been validated by numerical tests in a wide range of flow regimes. The novel equivalent scattering source reconstruction can be used for various transport processes, and the proposed numerical scheme is widely applicable in high-energy density engineering applications.

7.
Pharmacol Res ; 199: 107006, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38000562

RESUMO

Gallbladder and biliary diseases (GBDs) are one of the most common digestive diseases. The connections between GBDs and several organs other than the liver have gradually surfaced accompanied by the changes in people's diet structure and the continuous improvement of medical diagnosis technology. Among them, cholecardia syndrome that takes the heart as the important target of GBDs complications has been paid close attention. However, there are still no systematic report about its corresponding clinical manifestations and pathogenesis. This review summarized recent reported types of cholecardia syndrome and found that arrhythmia, myocardial injury, acute coronary syndrome and heart failure are common in the general population. Besides, the clinical diagnosis rate of intrahepatic cholestasis of pregnancy (ICP) and Alagille syndrome associated with gene mutation is also increasing. Accordingly, the underlying pathogenesis including abnormal secretion of bile acid, gene mutation, translocation and deletion (JAG1, NOTCH2, ABCG5/8 and CYP7A1), nerve reflex and autonomic neuropathy were further revealed. Finally, the potential treatment measures and clinical medication represented by ursodeoxycholic acid were summarized to provide assistance for clinical diagnosis and treatment.


Assuntos
Síndrome de Alagille , Colestase Intra-Hepática , Complicações na Gravidez , Feminino , Gravidez , Humanos , Síndrome de Alagille/complicações , Síndrome de Alagille/diagnóstico , Síndrome de Alagille/genética , Colestase Intra-Hepática/complicações , Colestase Intra-Hepática/tratamento farmacológico , Ácido Ursodesoxicólico/uso terapêutico
8.
Int J Biol Macromol ; 255: 128211, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37989429

RESUMO

A two-step method for preparing smart labels that can monitor food freshness through color change is presented. The conventional casting method for such labels is not cost-effective, as it uses organic solvents and requires additional cutting processes. Our method is more eco-friendly and customizable, as it uses water as the sole solvent and 3D printing as the fabrication technique. First, curcumin was encapsulated with soy protein isolate (SPI) by a pH-driven method involving hydrogen bonding and hydrophobic interactions. Subsequently, the SPI-curcumin complex was blended with gelatin to create a printable ink. The ink has suitable rheological properties for extrusion, with a yield stress of 400-600 Pa and a viscosity of 122.93-142.82 Pa·s at the optimal printing temperature. The complex modulus of the ink increases to above 2 × 103 Pa when cooled to 25 °C, indicating rapid gel formation. The application of these smart labels to minced meat demonstrated their ability to reflect its freshness by transitioning from yellow to red. Furthermore, the printability and mechanical properties of the labels can be adjusted by changing the glycerol/water ratio. This innovative approach is a promising solution for producing environmentally friendly and customizable smart labels for food freshness monitoring.


Assuntos
Curcumina , Curcumina/química , Proteínas de Soja/química , Impressão Tridimensional , Gelatina/química , Água
9.
Talanta ; 269: 125458, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008027

RESUMO

Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas enzymes have been widely applied for biosensor development, combined with various isothermal amplification strategies (IAS) to boost sensitivity and specificity. Currently, the unstable assay and tedious manipulation usually hinder its practical applications. Here, a Cas14a1-advanced LAMP assay (CALA) combined with Rapid Extraction of Bacterial Genomic DNA (REBGD) is proposed for pathogen detection. For rapid CALA, a single stranded fluorescence reporter and ssDNA-gold nanoparticles (AuNPs) are used as signal indicators to establish ultrasensitive and visual platforms. This assay displays precise detection of bacteria, which can achieve an ultrasensitive limit of detection (LOD) 10 aM target genomic DNA. Furthermore, the high reliability of pathogen diagnostic for contrived samples is validated through the rapid visual CALA platform, demonstrating the promising practical testing availability of pathogen detection.


Assuntos
Ouro , Nanopartículas Metálicas , Reprodutibilidade dos Testes , Bioensaio , DNA Bacteriano
10.
Nutr Hosp ; 41(1): 130-137, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37534522

RESUMO

Introduction: Objective: to evaluate leptin levels and its relation to nutritional status in Crohn's disease (CD). Methods: the study included 154 CD patients and healthy controls. Leptin level was determined before treatment. Nutrition levels were assessed using the Nutrition Risk Screening 2002 (NRS-2002) and Patient-Generated Subjective Global Assessment (PG-SGA). Indicators included body mass index (BMI), mid-arm circumference, the circumference of the upper-arm muscle, triceps skinfold thickness, and circumference of legs. Results: leptin levels differed between CD patients (1,025 ± 874 ng/ml) and controls (18,481,222 ng/ml). Significant differences were seen in NRS-2002, PG-SGA scores, BMI and other nutritional indicators. Negative correlations were observed between leptin and NRS-2002, PG-SGA scores, while positive correlations were observed with other nutritional indicators. The receiver operating characteristic (ROC) curve showed association between leptin and the diagnosis of CD, suggesting leptin concentration below 803.02 ng/ml as a threshold for CD. Conclusion: dysfunctional leptin regulation may relate to poor nutritional status associated with CD. The leptin level is thus an additional tool for evaluating CD patients, predicting disease activity and clinical response. Leptin may be a potential target for intervention in CD to improve nutritional status.


Introducción: Objetivo: evaluar los niveles de leptina y su relación con el estado nutricional en la enfermedad de Crohn (EC). Métodos: se incluyeron 154 pacientes con EC y controles sanos. El nivel de leptina se determinó antes del tratamiento. La situación nutricional se evaluó mediante el examen de riesgo nutricional 2002 (NRS-2002) y la Valoración Global Subjetiva Generada por el Paciente (VGS-GP). Los indicadores incluyen el índice de masa corporal (IMC), la circunferencia media del brazo, la circunferencia del músculo superior del brazo, el grosor del pliegue cutáneo del tríceps y la circunferencia de las piernas. Resultados: los niveles de leptina difirieron entre los pacientes con EC (1.025 ± 874 ng/ml) y los controles (18.481.222 ng/ml). Se observaron diferencias significativas en NRS-2002, puntajes de VGS-GP, IMC y otros indicadores nutricionales. Se observaron correlaciones negativas entre leptina y NRS-2002, puntuaciones de VGS-GP, mientras que se observaron correlaciones positivas con otros indicadores nutricionales. La curva ROC mostró asociación entre leptina y el diagnóstico de EC, sugiriendo concentraciones de leptina por debajo de 803,02 ng/ml como umbral para EC. Conclusión: puede relacionarse la alteración en la regulación de la leptina con la peor situación nutricional en enfermos con EC.La leptina puede ser un objetivo potencial para la intervención en EC a fin de mejorar el estado nutricional.


Assuntos
Doença de Crohn , Desnutrição , Humanos , Estado Nutricional , Doença de Crohn/diagnóstico , Leptina , Avaliação Nutricional , Desnutrição/diagnóstico
11.
Nat Chem ; 16(1): 114-121, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37723258

RESUMO

Single-crystal X-ray diffraction is a powerful characterization technique that enables the determination of atomic arrangements in crystalline materials. Growing or retaining large single crystals amenable to it has, however, remained challenging with covalent organic frameworks (COFs), especially suffering from post-synthetic modifications. Here we show the synthesis of a flexible COF with interpenetrated qtz topology by polymerization of tetra(phenyl)bimesityl-based tetraaldehyde and tetraamine building blocks. The material is shown to be flexible through its large, anisotropic positive thermal expansion along the c axis (αc = +491 × 10-6 K-1), as well as through a structural transformation on the removal of solvent molecules from its pores. The as-synthesized and desolvated materials undergo single-crystal-to-single-crystal transformation by reduction and oxidation of its imine linkages to amine and amide ones, respectively. These redox-induced linkage conversions endow the resulting COFs with improved stability towards strong acid; loading of phosphoric acid leads to anhydrous proton conductivity up to ca. 6.0 × 10-2 S cm-1.

12.
Int J Psychiatry Med ; : 912174231219041, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38047438

RESUMO

OBJECTIVE: This survey aimed to explore the relationships between burnout, moral injury, and suicidal/self-harm ideation among Chinese health professionals to provide a reference for protecting their mental health. METHOD: Health professionals were surveyed online using the Maslach Burnout Inventory-Human Services Survey for Medical Personnel, Patient Health Questionnaire-9, and the Moral Injury Symptoms Scale-Health Professional. RESULTS: In the analysis, 6146 eligible respondents were included in the study. The average participant age was 34.9 ± 8.5 years, and suicidal/self-harm ideation was detected in 2338 participants (38.0%). The prevalence of suicidal/self-harm ideation among those with severe burnout in the dimensions of emotional exhaustion, depersonalisation, and decreased personal accomplishment was significantly higher than those with mild burnout. The prevalence of suicidal/self-harm ideation among those with significant moral injury symptoms was higher than those without moral injury. Unconditional logistic regression analysis showed that those with moderate or severe emotional exhaustion, moderate or severe reduced sense of professional accomplishment and moderate or severe depersonalisation had increased risks of suicidal/self-harm ideation. CONCLUSIONS: Structural equation modelling demonstrated that burnout significantly mediated the relationship between moral injury and suicidal/self-harm ideation. The proportion of mediation (PM) by burnout was 43.0%. Burnout and moral injury were potential predictors of suicidal/self-harm ideation among health professionals. Both moral injury and burnout had positive and direct effects on suicidal/self-harm ideation, and burnout was a mediator in this relationship among Chinese health professionals. Therefore, to alleviate the moral injury and subsequent burnout of healthcare workers and enhance their mental qualities, active interventions should be developed in the future.

13.
Anal Chem ; 95(51): 18898-18906, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38096497

RESUMO

Surface plasmon resonance microscopy (SPRM), based on the scattering of single molecules at the interface, is a highly efficient analytical platform widely used in the fields of biology and chemistry. Due to the interference scattering, the imaging pattern exhibits typical parabolic tail and phase transition features, providing a quantitative means of observing the changes in the physical and chemical properties of single molecules. In this work, we reported another unique asymmetric parabolic distribution pattern resulting from polarization conversion in the experiment based on SPRM. This microscopic-level feature is derived from the switching between SPR resonant and nonresonant states. Starting from energy flux theory, we constructed an analysis model and conducted full-wave numerical simulations to verify the experimental results. Furthermore, we demonstrate that the optical rotation induced by chiral thin films can be directly measured through imaging with asymmetric features, providing valuable insights into the field of chiral materials. The quantitative interpretation of asymmetric scattering not only advances the fundamental understanding of the imaging mechanism of SPRM, but also opens up possibilities for utilizing this polarization-sensitive characteristic for single-particle detection and sensing in the future.

14.
J Am Chem Soc ; 145(46): 25332-25340, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37944150

RESUMO

Rational control and understanding of isomerism are of significance but still remain a great challenge in reticular frameworks, in particular, for covalent organic frameworks (COFs) due to the complicated synthesis and energy factors. Herein, reaction of 3,3',5,5'-tetra(4-formylphenyl)-2,2',6,6'-tetramethoxy-1,1'-biphenyl (TFTB) with 3,3',5,5'-tetrakis(4-aminophenyl)bimesityl (TAPB) under different reaction conditions affords single crystals of two 3D COF isomers, namely, USTB-20-dia and USTB-20-qtz. Their structures with resolutions up to 0.9-1.1 Å have been directly solved by three-dimensional electron diffraction (3D ED) and synchrotron single crystal X-ray diffraction, respectively. USTB-20-dia and USTB-20-qtz show rare 2 × 2-fold interpenetrated dia-b nets and 3-fold interpenetrated qtz-b frameworks. Comparative studies of the crystal structures of these COFs and theoretical simulation results indicate the crucial role of the flexible molecular configurations of building blocks in the present interpenetrated topology isomerism. This work not only presents the rare COF isomers but also gains an understanding of the formation of framework isomerism from both single crystal structures and theoretical simulation perspectives.

15.
J Am Chem Soc ; 145(49): 26711-26719, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38031299

RESUMO

In situ and accurate measurement of the structure and dynamics of interfacial water in the hydrogen evolution reaction (HER) is a well-known challenge because of the coupling of water among varied structures and its dual role as reactants and solvents. Further, the interference of bulk water and intricate interfacial interactions always hinders the probing of interfacial water. Surface-enhanced infrared absorption spectroscopy is extremely sensitive for the measurement of interfacial water; herein, we develop a nanoconfinement strategy by introducing nonaqueous ionic liquids to decouple and tailor the water structure in the electric double layer and further combined with molecular dynamics simulations, successfully gaining the correlation between isolated water, water clusters, and the water network with HER activity. Our results clearly disclosed that the potential-dependent asymmetric four-coordinated water network, whose connectivity could be regulated by hydrophilic and hydrophobic cations, was positively correlated with HER activity, which provided a pioneering guidance framework for revealing the function of water in catalysis, energy, and surface science.

16.
Cureus ; 15(10): e47574, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38021786

RESUMO

Background The poor prognosis of lung adenocarcinoma (LUAD) has been confirmed by a large number of studies, so it is necessary to construct a prognosis model. In addition, exosome is closely related to tumors, but there are few studies on exosome-related long non-coding RNA (lncRNA) (ExolncRNA). Methods In this study, we designed a prognostic model, exosome-related lncRNA-based signature (ExoLncSig), using ExolncRNA expression profiles of LUAD patients from The Cancer Genome Atlas (TCGA). ExolncRNAs were identified through univariate and multivariate and Lasso analyses. Subsequently, based on the ExoLncSig, gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, immune function and immunotherapy analysis, drug screening, and so on were performed. Results AC026355.2, AC108136.1, AL590428.1, and LINC01312 were examined to establish the ExoLncSig. Gene enrichment analysis identified potential prognostic markers and therapeutic targets, including human leukocyte antigen (HLA), parainflammation, chemokine receptor (CCR), antigen-presenting cell (APC) co-inhibition, cancer-associated fibroblast (CAF), and myeloid-derived suppressor cell (MDSC). Moreover, we ascertained that the high-risk subgroup exhibits heightened susceptibility to pharmaceutical agents. Conclusion Our findings indicate that ExoLncSig holds promise as a valuable prognostic marker in LUAD. Furthermore, the immunogenic properties of ExolncRNAs may pave the way for the development of a therapeutic vaccine against LUAD.

18.
Angew Chem Int Ed Engl ; 62(49): e202312603, 2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-37847126

RESUMO

Immunotherapies have shed light on the treatment of many cancers, but have not improved the outcomes of glioma (GBM). Here, we demonstrated that suppressor of cytokine signaling 1 (SOCS1) was associated with the GBM-associated immunosuppression and developed a multifunctional nanomedicine, which silenced SOCS1 in the tumor microenvironment (TME) of GBM and triggered strong antitumor immunity against GBM. Synthetic high-density lipoprotein (sHDL) was selected as the nanocarrier and a peptide was used to facilitate the blood-brain-barrier (BBB) penetration. The nanocarrier was loaded with a small interfering RNA (siRNA), a peptide, and an adjuvant to trigger antitumor immunity. The nanomedicine concentrated on the TME in vivo, further promoting dendritic cell maturation and T cell proliferation, triggering strong cytotoxic T lymphocyte responses, and inhibiting tumor growth. Our work provides an alternative strategy to simultaneously target and modulate the TME in GBM patients and points to an avenue for enhancing the efficacy of immunotherapeutics.


Assuntos
Glioma , Microambiente Tumoral , Humanos , Proteína 1 Supressora da Sinalização de Citocina/genética , Lipoproteínas HDL , Nanomedicina , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Glioma/terapia , RNA Interferente Pequeno/genética , Linhagem Celular Tumoral
19.
Cell Signal ; 112: 110925, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37839545

RESUMO

Heterochromatin Protein 1 (HP1) is a major component of heterochromatin. Multiple proteins have been shown to interact with HP1 with the HP1-binding motif PxVxL/I, thereby affecting heterochromatin stability. The HP1-interacting proteins include the signal transducer and activator of transcription (STAT) protein, which can be regulated by phosphorylation on a tyrosine around amino acid 700 in the carboxyl terminus. Previous research has shown that unphosphorylated STAT (uSTAT) binds to HP1 via a PxVxI HP1-binding motif and maintains the stability of heterochromatin, while phosphorylated STAT (pSTAT) dissociates from HP1, resulting in heterochromatin disruption. To understand the theoretical basis of the biochemical observations, we employed computational modeling to investigate STAT-HP1 binding configurations and the effect of STAT phosphorylation on their interaction. Using STAT3 and HP1α protein structures for molecular docking and thermodynamic calculations, our computations predict that uSTAT homodimers have a higher affinity for HP1 and a lower affinity for DNA than pSTAT homodimers, and that phosphorylation induces a conformational change in STAT, shifting its binding preference from HP1 to DNA. The results of our modeling studies support the idea that phosphorylation drives STAT from HP1-binding to DNA-binding, suggesting a potential role for uSTAT in both maintaining and initiating heterochromatin formation.


Assuntos
Homólogo 5 da Proteína Cromobox , Heterocromatina , Simulação de Acoplamento Molecular , Proteínas Cromossômicas não Histona/metabolismo , DNA
20.
Science ; 381(6665): 1468-1474, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37769102

RESUMO

3D printing of inorganic materials with nanoscale resolution offers a different materials processing pathway to explore devices with emergent functionalities. However, existing technologies typically involve photocurable resins that reduce material purity and degrade properties. We develop a general strategy for laser direct printing of inorganic nanomaterials, as exemplified by more than 10 semiconductors, metal oxides, metals, and their mixtures. Colloidal nanocrystals are used as building blocks and photochemically bonded through their native ligands. Without resins, this bonding process produces arbitrary three-dimensional (3D) structures with a large inorganic mass fraction (~90%) and high mechanical strength. The printed materials preserve the intrinsic properties of constituent nanocrystals and create structure-dictated functionalities, such as the broadband chiroptical responses with an anisotropic factor of ~0.24 for semiconducting cadmium chalcogenide nanohelical arrays.

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