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1.
Angew Chem Int Ed Engl ; 63(14): e202319480, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38317379

RESUMO

Controlled synthesis of lead-halide perovskite crystals is challenging yet attractive because of the pivotal role played by the crystal structure and growth conditions in regulating their properties. This study introduces data-driven strategies for the controlled synthesis of oriented quasi-spherical CsPbBr3, alongside an investigation into the synthesis mechanism. High-throughput rapid characterization of absorption spectra and color under ultraviolet illumination was conducted using 23 possible ligands for the synthesis of CsPbBr3 crystals. The links between the absorption spectra slope (difference in the absorbance at 400 nm and 450 nm divided by a wavelength interval of 50 nm) and crystal size were determined through statistical analysis of more than 100 related publications. Big data analysis and machine learning were employed to investigate a total of 688 absorption spectra and 652 color values, revealing correlations between synthesis parameters and properties. Ex situ characterization confirmed successful synthesis of oriented quasi-spherical CsPbBr3 perovskites using polyvinylpyrrolidone and Acacia. Density functional theory calculations highlighted strong adsorption of Acacia on the (110) facet of CsPbBr3. Optical properties of the oriented quasi-spherical perovskites prepared with these data-driven strategies were significantly improved. This study demonstrates that data-driven controlled synthesis facilitates morphology-controlled perovskites with excellent optical properties.

2.
Chem Sci ; 14(35): 9409-9417, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37712014

RESUMO

Mn(diimine)(CO)3X (X = halide) complexes are critical components of chromophores, photo- and electrocatalysts, and photoactive CO-releasing molecules (photoCORMs). While these entities have been incorporated into metal-organic frameworks (MOFs), a detailed understanding of the photochemical and chemical processes that occur in a permanently porous support is lacking. Here we site-isolate and study the photochemistry of a Mn(diimine)(CO)3Br moiety anchored within a permanently porous MOF support, allowing for not only the photo-liberation of CO from the metal but also its escape from the MOF crystals. In addition, the high crystallinity and structural flexibility of the MOF allows crystallographic snapshots of the photolysis products to be obtained. We report these photo-crystallographic studies in the presence of coordinating solvents, THF and acetonitrile, showing the changing coordination environment of the Mn species as CO loss proceeds. Using time resolved experiments, we report complementary spectroscopic studies of the photolysis chemistry and characterize the final photolysis product as a possible Mn(ii) entity. These studies inform the chemistry that occurs in MOF-based photoCORMs and where these moieties are employed as catalysts.

3.
Front Neurosci ; 16: 1026610, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312016

RESUMO

Psoriasis is a chronic, autoimmune disorder that is related to mental health disorders such as depression. However, few studies have focused on the features of brain activity in psoriasis patients with depression (PPD) and the association between brain activity and disease severity. A total of 29 PPD and 24 healthy controls were involved in this study, and all participants underwent resting-state functional magnetic resonance imaging (fMRI) scanning. The psoriasis area and severity index (PASI) and the self-rating depression scale (SDS) were used to measure clinical symptoms. Compared with HCs, PPD patients showed increased fractional amplitude of low-frequency fluctuation (fALFF) in the Frontal_Mid_L and increased functional connectivity (FC) between the hypothalamus-R and the Cingulum_Mid_R. Correlation analysis suggested a positive correlation between PASI and SDS scores in PPD, while the fALFF and FC values were negatively correlated with their SDS and PASI scores. These brain regions may be associated with the development of depressive symptoms and disease severity in psoriasis patients.

4.
Small ; 18(33): e2201642, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35843870

RESUMO

The development of advanced electronic devices is boosting many aspects of modern technology and industry. The ever-increasing demand for advanced electrical devices and integrated circuits calls for the design of novel materials, with superior properties for the improvement of working performance. In this review, a detailed overview of the synthesis strategies of 2D metal organic frameworks (MOFs) acquiring growing attention is presented, as a basis for expansion of novel key materials in electrical devices and integrated circuits. A framework of controllable synthesis routes to be implanted in the synthesis strategies of 2D materials and MOFs is described. In short, the synthesis methods of 2D MOFs are summarized and discussed in depth followed by the illustrations of promising applications relating to various electrical devices and integrated circuits. It is concluded by outlining how 2D MOFs can be synthesized in a simpler, highly efficient, low-cost, and more environmentally friendly way which can open up their applicable opportunities as key materials in advanced electrical devices and integrated circuits, enabling their use in broad aspects of the society.


Assuntos
Estruturas Metalorgânicas , Eletricidade
5.
Microb Pathog ; 167: 105560, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35504350

RESUMO

BACKGROUND: Guttate psoriasis (GP) and psoriasis plaques (PP) are common subtypes of psoriasis. Previous studies have fully researched the association between psoriasis and gut microbiota. However, the differences in gut microbiota between GPs and PPs are still unknown. METHODS: Fecal samples were collected from 30 psoriatic patients (15 GP and 15 PP) and 15 healthy subjects. Metagenomic sequencing was then used to compare gut microbiota compositions and corresponding genetic and metabolic features between GP and PP. RESULTS: We found that the genus Megamonas was increased in PP and reduced in GP. The genus Eubacterium was increased in GP and decreased in PP. Ten KEGG pathway were significantly enriched in GP: bacterial secretion system, ribosome, sphingolipid signaling pathway, steroid hormone biosynthesis, complement and coagulation cascades, proteoglycans in cancer, FOXO signaling pathway, cGMP-PKG signaling pathway, insulin resistance, and Epstein-Barr virus infection. Ten metabolites were significantly differentially abundant between GP and PP. Among them, thiamine, biotin, butylamine, phenylethylamine, folic acid, 1,2-propanediol, and 4-aminobutyrate were enriched in PP and l-glutamate, l-glutamine, and propanoate were enriched in GP. CONCLUSIONS: These results provide a theoretical basis for the microbiome-guided stratification of patients with psoriasis.


Assuntos
Infecções por Vírus Epstein-Barr , Microbioma Gastrointestinal , Psoríase , Microbioma Gastrointestinal/genética , Herpesvirus Humano 4 , Humanos , Metagenômica
6.
Transl Oncol ; 21: 101424, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35477065

RESUMO

Cancer is the most acute disease and the leading cause of patient death worldwide. Both chemotherapy and molecular-based therapies play an important role in curing cancer. However, the median and overall survival of patients is poor. To date, immune therapies have changed the treatment methods for cancer patients. Programmed death ligand 1 (PD-L1, also known as B-H1, CD274) is a well-studied tumor antigen. PD-L1 is overexpressed in colon cancer, lung cancer, and so on and plays a vital role in cancer development. In this study, anti-PD-L1 single-domain antibodies were identified from recombinant human PD-L1 (rhPD-L1)-immunized llamas. Then, we generated a novel multifunctional anti-PD-L1-CD16a-IL15 antibody targeting PD-L1-positive tumor cells. Anti-PD-L1-CD16a-IL15 was constructed by linking the Interleukin-2 (IL-2) signal peptide, anti-PD-L1 single domain antibody (anti-PD-L1-VHH) and anti-cluster of differentiation 16a single domain antibody (anti-CD16a-VHH), and Interleukin-15/Interleukin-15 receptor alpha (IL15/IL-15Rα). This anti-PD-L1-CD16a-IL15 fusion protein can be expressed and purified from HEK-293F cells. In vitro, our data showed that the anti-PD-L1-CD16a-IL15 fusion protein can recruit T cells and drive natural killer cells (NK) with specific killing of PD-L1-overexpressing tumor cells. Furthermore, in the xenograft model, the anti-PD-L1-CD16a-IL15 fusion protein inhibited tumor growth with human peripheral blood mononuclear cells (PBMCs). These data suggested that the anti-PD-L1-CD16a-IL15 fusion protein has a latent function in antitumour activity, with better guidance for future cancer immunotherapy.

7.
Fish Shellfish Immunol ; 124: 572-578, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35483598

RESUMO

AP-1 is an important transcription factor for cell proliferation/differentiation and animal immunity/development; however, its role in research in shellfish is poorly understood. Here, the cDNA of AP-1 gene from Pinctada fucata martensii was characterized. Its expression was detected in all six examined tissues, and a high level was observed in the gill and hepatopancreas. Analysis of the developmental transcriptomes showed that the PmAP-1 gene expression levels were high during D-stage larval and spat stages. The gene also exhibited a significantly high expression under cold tolerance stress. SNP analysis of the exon region and 5' flanking region of PmAP-1 revealed 19 SNPs of which 8 showed significant differences between cold tolerance selection line and base stock. Furthermore, three haplotypes generated by the SNPs of PmAP-1 were significantly associated with cold tolerance, respectively.These results suggest that the PmAP-1 gene plays an important role in the response of P. f. martensii to low temperature stress. These SNPs and haplotypes of PmAP-1 may be related to the cold tolerance of P. f. martensii, and could be candidate markers potentially for further selective breeding.


Assuntos
Pinctada , Animais , Temperatura Baixa , Regulação da Expressão Gênica , Pinctada/genética , Pinctada/metabolismo , Fator de Transcrição AP-1/genética , Transcriptoma
8.
Biosci Rep ; 42(1)2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35005769

RESUMO

PURPOSE: Our previous data indicated that miR-24-3p is involved in the regulation of vascular endothelial cell (EC) proliferation and migration/invasion. However, whether IL-1ß affects hypoxic HUVECs by miR-24-3p is still unclear. Therefore, the present study aimed to investigate the role and underlying mechanism of interleukin 1ß (IL-1ß) in hypoxic HUVECs. METHODS: We assessed the mRNA expression levels of miR-24-3p, hypoxia-inducible factor-1α (HIF1A) and NF-κB-activating protein (NKAP) by quantitative real-time polymerase chain reaction (RT-qPCR). ELISA measured the expression level of IL-1ß. Cell counting kit-8 (CCK-8) assays evaluated the effect of miR-24-3p or si-NKAP+miR-24 on cell proliferation (with or without IL-1ß). Transwell migration and invasion assays were used to examine the effects of miR-24-3p or si-NKAP+miR-24-3p on cell migration and invasion (with or without IL-1ß). Luciferase reporter assays were used to identify the target of miR-24-3p. RESULTS: We demonstrated that in acute myocardial infarction (AMI) patient blood samples, the expression of miR-24-3p is down-regulated, the expression of IL-1ß or NKAP is up-regulated, and IL-1ß or NKAP is negatively correlated with miR-24-3p. Furthermore, IL-1ß promotes hypoxic HUVECs proliferation by down-regulating miR-24-3p. In addition, IL-1ß also significantly promotes the migration and invasion of hypoxic HUVECs; overexpression of miR-24-3p can partially rescue hypoxic HUVECs migration and invasion. Furthermore, we discovered that NKAP is a novel target of miR-24-3p in hypoxic HUVECs. Moreover, both the overexpression of miR-24-3p and the suppression of NKAP can inhibit the NF-κB/pro-IL-1ß signaling pathway. However, IL-1ß mediates suppression of miR-24-3p activity, leading to activation of the NKAP/NF-κB pathway. In conclusion, our results reveal a new function of IL-1ß in suppressing miR-24-3p up-regulation of the NKAP/NF-κB pathway.


Assuntos
Células Endoteliais , Interleucina-1beta , MicroRNAs , Proliferação de Células , Células Endoteliais/citologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Interleucina-1beta/genética , MicroRNAs/genética , Infarto do Miocárdio , NF-kappa B/genética , Proteínas Repressoras
9.
Biomed Pharmacother ; 137: 111065, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33540138

RESUMO

The occurrence, progression and recurrence of psoriasis are thought to be related to mood and psychological disorders such as depression. Psoriasis can lead to depression, and depression, in turn, exacerbates psoriasis. No specific mechanism can explain the association between psoriasis and depression. The gut-brain-skin axis has been used to explain correlations among the gut microbiota, emotional states and systemic and skin inflammation, and this axis may be associated with overlapping mechanisms between psoriasis and depression. Therefore, in the context of the gut-brain-skin axis, we systematically summarized and comparatively analysed the inflammatory and immune mechanisms of psoriasis and depression and illustrated the dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and the gut microbiota. This review provides a theoretical basis and new targets for the treatment of psoriasis and depression.


Assuntos
Bactérias/imunologia , Encéfalo/imunologia , Depressão/imunologia , Microbioma Gastrointestinal , Intestinos/microbiologia , Psoríase/imunologia , Pele/imunologia , Afeto , Bactérias/metabolismo , Encéfalo/metabolismo , Depressão/metabolismo , Depressão/microbiologia , Depressão/psicologia , Disbiose , Emoções , Humanos , Mediadores da Inflamação/metabolismo , Neuroimunomodulação , Neuropeptídeos/metabolismo , Psoríase/metabolismo , Psoríase/microbiologia , Psoríase/psicologia , Transdução de Sinais , Pele/metabolismo
10.
J Am Chem Soc ; 141(29): 11471-11480, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31306004

RESUMO

Complexes with weakly coordinating ligands are often formed in chemical reactions and can play key roles in determining the reactivity, particularly in catalytic reactions. Using time-resolved X-ray absorption fine structure (XAFS) spectroscopy in combination with time-resolved IR (TRIR) spectroscopy and tungsten hexacarbonyl, W(CO)6, we are able to structurally characterize the formation of an organometallic alkane complex, determine the W-C distances, and monitor the reactivity with silane to form an organometallic silane complex. Experiments in perfluorosolvents doped with xenon afford initially the corresponding solvated complex, which is sufficiently reactive in the presence of Xe that we can then observe the coordination of Xe to the metal center, providing a unique insight into the metal-xenon bonding. These results offer a step toward elucidating the structure, bonding, and chemical reactivity of transient species by X-ray absorption spectroscopy, which has sensitivity to small structural changes. The XAFS results indicate that the bond lengths of metal-alkane (W-H-C) bond in W(CO)5(heptane) as 3.07 (±0.06) Å, which is longer than the calculated W-C (2.86 Å) for binding of the primary C-H, but shorter than the calculated W-C (3.12 Å) for the secondary C-H. A statistical average of the calculated W-C alkane bond lengths is 3.02 Å, and comparison of this value indicates that the value derived from the XAFS measurements is averaged over coordination of all C-H bonds consistent with alkane chain walking. Photolysis of W(CO)6 in the presence of HSiBu3 allows the conversion of W(CO)5(heptane) to W(CO)5(HSiBu3) with an estimated W-Si distance of 3.20 (±0.03) Å. Time-resolved TRIR and XAFS experiments following photolysis of W(CO)6 in perfluoromethylcyclohexane (PFMCH) allows the characterization of W(CO)5(PFMCH) with a W-F distance of 2.65 (±0.06) Å, and doping PFMCH with Xe allows the characterization of W(CO)5Xe with a W-Xe bond length of 3.10 (±0.02) Å.

11.
J Am Chem Soc ; 140(13): 4534-4542, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29537264

RESUMO

The ground and excited state photophysical properties of a series of fac-[Re(L)(CO)3(α-diimine)] n+ complexes, where L = Br-, Cl-, 4-dimethylaminopyridine (dmap) and pyridine (py) have been extensively studied utilizing numerous electronic and vibrational spectroscopic techniques in conjunction with a suite of quantum chemical methods. The α-diimine ligand consists of 1,10-phenanthroline with the highly electron donating triphenylamine (TPA) appended in the 5 position. This gives rise to intraligand charge transfer (ILCT) states lying lower in energy than the conventional metal-to-ligand charge transfer (MLCT) state, the energies of which are red and blue-shifted, respectively, as the ancillary ligand, L becomes more electron withdrawing. The emitting state is 3ILCT in nature for all complexes studied, characterized through transient absorption and emission, transient resonance Raman (TR2), time-resolved infrared (TRIR) spectroscopy and TDDFT calculations. Systematic modulation of the ancillary ligand causes unanticipated variation in the 3ILCT lifetime by 2 orders of magnitude, ranging from 6.0 µs for L = Br- to 27 ns for L = py, without altering the nature of the excited state formed or the relative order of the other CT states present. Temperature dependent lifetime measurements and quantum chemical calculations provide no clear indication of close lying deactivating states, MO switching, contributions from a halide-to-ligand charge transfer (XLCT) state or dramatic changes in spin-orbit coupling. It appears that the influence of the ancillary ligand on the excited state lifetime could be explained in terms of energy gap law, in which there is a correlation between ln( knr) and Eem with a slope of -21.4 eV-1 for the 3ILCT emission.

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