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1.
Front Nutr ; 11: 1407454, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903618

RESUMO

Background: Previous findings imply a potential positive association between BMI and all-cause mortality in individuals with psoriasis, yet direct evidence remains absent. This study aimed to fill this gap. Methods: We utilized data from the National Health and Nutrition Examination Survey (NHANES) for the periods 2003-2006 and 2009-2014. Participants' BMI was categorized as lean (<25), overweight (25 ≤ BMI < 30), and obese (BMI ≥ 30). Psoriasis status was determined through self-reporting. The main outcome measured was all-cause mortality up to December 2019. We accounted for multiple covariates, such as sociodemographic factors and histories of smoking and alcohol consumption. Our statistical analyses mainly included Kaplan-Meier survival analysis, Restricted Cubic Spline (RCS) and Multivariate Cox Regression (MCR). We also applied propensity score matching (PSM) to verify the robustness of our findings. Results: Among 22,876 participants, 618 (2.70%) reported a history of psoriasis. An overall effect from the MCR analysis showed that, among individuals with psoriasis, a higher baseline BMI was independently associated with an increased risk of all-cause mortality, noting a 5.5% rise in mortality risk per BMI unit [hazard ratio (HR) = 1.055, 95% CI: 1.004-1.110, p = 0.035]. This significant relationship persisted after PSM. A statistically significant positive correlation was consistent among males, smokers, and individuals younger than 60. However, no such association was found in individuals without a history of psoriasis. Additionally, no significant difference in mortality risk was found between lean and overweight groups with psoriasis, according to the RCS regression and stratified analysis. Conclusion: Our findings indicated a trend that, higher BMIs significantly correlated with increased risks of all-cause mortality in people with psoriasis, particularly among obese ones. However, the impact of being overweight on this relationship remains underexplored. Moreover, the necessity to employ alternative metrics beyond BMI for body fat assessment to further investigate these associations is critical.

3.
Nat Chem ; 16(6): 893-900, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38641678

RESUMO

Metal-free catalysts offer a desirable alternative to traditional metal-based electrocatalysts. However, metal-free catalysts, featuring defined active sites, rarely show activities as promising as metal-based materials. Here we report 2-thiolimidazole as an efficient metal-free catalyst for selective electrocatalytic hydrogenation of acetylene into ethylene. Under alkaline conditions, the sulfhydryl and imino groups of 2-thiolimidazole are spontaneously deprotonated into dianions. Deprotonation thus enriches the negative charges of pyridinic N sites in 2-thiolimidazole to enhance the adsorption of electrophilic acetylene through the σ-configuration. Ethylene partial current densities show a volcano relationship with the negative charges of the pyridinic N sites in various imidazole derivatives. Consequently, the deprotonated 2-thiolimidazole exhibits an ethylene partial current density and faradaic efficiency competitive with metal-based catalysts like Cu and Pd. This work highlights the tunability and promising potential of metal-free molecules in electrocatalysis.

4.
J Comput Chem ; 45(3): 159-169, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37698288

RESUMO

Using full configuration interaction (FCI) and multi-reference configuration interaction methods (MRCI), reliable geometrical and energetic references for Bn (n = 1-4) clusters were established. The accuracy of the computed results was confirmed by comparison with available experimental data. Benchmark calculations indicated that B97D3, B97D, VSXC, HCTH407, BP86 and CCSD(T) methods provided reasonable results for structural parameters, with mean absolute error (MAEs) within 0.020 Å. Among the tested density functional theory (DFT) methods, the VSXC functional showed the best performance in predicting the relative energies of B1 B4 with a MAE of 12.8 kJ mol-1 . Besides, B1B95, B971, TPSS, B3LYP, and BLYP functionals exhibited reasonable performance with MAE values of less than 15.0 kJ mol-1 . T1 diagnostic values between 0.035 and 0.109 at the CCSD(T) level revealed strong correlations in B2 B4 clusters, highlighting the need for caution in using CCSD(T) as an energy reference for small boron clusters. The methods of CCSDT, CCSDT(Q) and CCSDT[Q], which incorporate three-electron and four-electron excitations, effectively improved the accuracy of the energy calculations.

5.
Front Med (Lausanne) ; 10: 1232127, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38155665

RESUMO

Objective: This study explored the efficacy of acupuncture and metformin in enhancing insulin sensitivity among women with polycystic ovary syndrome (PCOS) and insulin resistance (IR), distinguishing between overweight/obese and lean groups. Methods: A post-hoc analysis of a randomized trial (NCT02491333) was undertaken. Participants were women aged 18-40 with PCOS and IR. They were randomized to receive true acupuncture with a placebo, metformin with sham acupuncture, or sham acupuncture with a placebo for 4 months, with follow-up visits over 3 months. Our study, involving 339 women, assessed the differential impact of acupuncture and metformin on insulin sensitivity in overweight/obese [body mass index (BMI) ≥ 24] versus lean women (BMI < 24). Primary outcomes measured changes in the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) at 4 and 7 months. Secondary outcomes assessed changes in glucose area under the curve (glucoseAUC) during the oral glucose tolerance test (OGTT) and BMI changes at 4 months. Results: Overweight/obese participants were generally older with higher measurements in various health metrics, but lower levels in specific hormonal metrics compared to lean women (p < 0.05). Among overweight/obese women, metformin outperformed acupuncture in reducing HOMA-IR levels (p = 0.004) and showed a significant drop from the baseline after 4 months (p < 0.05). In contrast, acupuncture's effect on HOMA-IR did not significantly differ from sham acupuncture at 4 and 7 months. For lean women, metformin and acupuncture showed comparable improvements in HOMA-IR, with notable declines at 4 and 7 months (p < 0.05). Acupuncture proved more beneficial for lean women than their overweight/obese counterparts after 4 months (p = 0.021). Conclusion: In overweight/obese women with PCOS and IR, acupuncture was less effective than metformin in enhancing insulin sensitivity. However, in lean women, acupuncture's efficacy was comparable to metformin. Further studies are required to validate these observations.

6.
RSC Adv ; 13(34): 23984-23990, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37577084

RESUMO

Searching for the maximum coordination number (CN) in planar species with novel bonding patterns has fascinated chemists for many years. Using the experimentally observed polyynic cyclo[18]carbon D9h C18 and theoretically predicted polyynic cyclo[14]carbon D7h C14 as effective ligands and based on extensive first-principles theory calculations, we predict herein their perfect planar alkaline-metal-centered complexes D9h Cs©C18+ (1) and D7h Na©C14+ (4) which as the global minima of the systems possess the record coordination numbers of CN = 18 and 14 in planar polyynic species, respectively. More interestingly, detailed energy decomposition and adaptive natural density partitioning bonding analyses indicate that the hypercoordinate alkaline-metal centers in these complexes exhibit obvious transition metal behaviors, with effective in-plane (π-6s)σ, (π-7p)σ, and (π-5d)σ coordination bonds formed in Cs©C18+ (1) and (π-3s)σ, (π-3p)σ, and (π-3d)σ coordination interactions fabricated in Na©C14+ (4) to dominate the overall attractive interactions between the metal center and its cyclo[n]carbon ligand. Similarly, alkaline-metal-centered planar Cs Cs©C17B (2), C2v Cs©C17- (3), C2v Na©C13B (5), and C2v Na©C13- (6) have also been obtained with CN = 18, 17, 14, and 13, respectively.

7.
Mediators Inflamm ; 2023: 7992140, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152370

RESUMO

Liver hepatocellular carcinoma (LIHC) is a highly lethal malignant tumor originating from the digestive system, which is a serious threat to human health. In recent years, immunotherapy has shown significant therapeutic effects in the treatment of LIHC, but only for a minority of patients. The basement membrane (BM) plays an important role in the occurrence and development of tumors, including LIHC. Therefore, this study is aimed at establishing a risk score model based on basement membrane-related genes (BMRGs) to predict patient prognosis and response to immunotherapy. First, we defined three patterns of BMRG modification (C1, C2, and C3) by consensus clustering of BMRG sets and LIHC transcriptome data obtained from public databases. Survival analysis showed that patients in the C2 group had a better prognosis, and Gene Set Variation Analysis (GSVA) revealed that the statistically significant pathways were mainly enriched in the C2 group. Moreover, we performed Weighted Correlation Network Analysis (WGCNA) on the above three subgroups and obtained 179 intersecting genes. We further applied function enrichment analyses, and the results demonstrated that they were mainly enriched in metabolism-related pathways. Furthermore, we conducted the LASSO regression analysis and obtained 4 BMRGs (MPV17, GNB1, DHX34, and MAFG) that were significantly related to the prognosis of LIHC patients. We further constructed a prognostic risk score model based on the above genes, which was verified to have good predictive performance for LIHC prognosis. In addition, we analyzed the correlation between the risk score and the tumor immune microenvironment (TIM), and the results showed that the high-risk scoring group tended to be in an immunosuppressed status. Finally, we investigated the relationship between the risk score and LIHC immune function. The results demonstrated that the risk score was closely related to the expression levels of multiple immune checkpoints. Patients in the low-risk group had significantly higher IPS scores, and patients in the high-risk group had lower immune escape and TIDE score. In conclusion, we established a novel risk model based on BMRGs, which may serve as a biomarker for prognosis and immunotherapy in LIHC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas/genética , Membrana Basal , Prognóstico , Microambiente Tumoral , RNA Helicases
8.
Angew Chem Int Ed Engl ; 62(26): e202303433, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37083026

RESUMO

A homogeneous manganese-catalyzed cross-coupling of two secondary alcohols for the divergent synthesis of γ-disubstituted alcohols and ß-disubstituted ketones is reported. Employing the well-defined Mn-MACHOPh as the catalyst, this novel protocol has a broad substrate scope with good functional group tolerance and affords a diverse library of valuable disubstituted alcohols and ketones in moderate to good yields. The strong influence of the reaction temperature on the selective formation of alcohol products was theorized in preliminary DFT studies. Studies have shown that the Gibbs free energy of the formation of alcohols is thermodynamically more favourable than corresponding ketones at a lower temperature.


Assuntos
Álcoois , Manganês , Cetonas , Oxirredução , Estrutura Molecular , Catálise
9.
Redox Biol ; 62: 102696, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37058999

RESUMO

As the essential amino acids, branched-chain amino acid (BCAA) from diets is indispensable for health. BCAA supplementation is often recommended for patients with consumptive diseases or healthy people who exercise regularly. Latest studies and ours reported that elevated BCAA level was positively correlated with metabolic syndrome, diabetes, thrombosis and heart failure. However, the adverse effect of BCAA in atherosclerosis (AS) and its underlying mechanism remain unknown. Here, we found elevated plasma BCAA level was an independent risk factor for CHD patients by a human cohort study. By employing the HCD-fed ApoE-/- mice of AS model, ingestion of BCAA significantly increased plaque volume, instability and inflammation in AS. Elevated BCAA due to high dietary BCAA intake or BCAA catabolic defects promoted AS progression. Furthermore, BCAA catabolic defects were found in the monocytes of patients with CHD and abdominal macrophages in AS mice. Improvement of BCAA catabolism in macrophages alleviated AS burden in mice. The protein screening assay revealed HMGB1 as a potential molecular target of BCAA in activating proinflammatory macrophages. Excessive BCAA induced the formation and secretion of disulfide HMGB1 as well as subsequent inflammatory cascade of macrophages in a mitochondrial-nuclear H2O2 dependent manner. Scavenging nuclear H2O2 by overexpression of nucleus-targeting catalase (nCAT) effectively inhibited BCAA-induced inflammation in macrophages. All of the results above illustrate that elevated BCAA promotes AS progression by inducing redox-regulated HMGB1 translocation and further proinflammatory macrophage activation. Our findings provide novel insights into the role of animo acids as the daily dietary nutrients in AS development, and also suggest that restricting excessive dietary BCAA consuming and promoting BCAA catabolism may serve as promising strategies to alleviate and prevent AS and its subsequent CHD.


Assuntos
Aterosclerose , Proteína HMGB1 , Animais , Humanos , Camundongos , Aminoácidos de Cadeia Ramificada/metabolismo , Aminoácidos de Cadeia Ramificada/farmacologia , Aterosclerose/etiologia , Estudos de Coortes , Peróxido de Hidrogênio , Inflamação/induzido quimicamente , Macrófagos/metabolismo
10.
J Hepatocell Carcinoma ; 10: 43-55, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36660412

RESUMO

Purpose: In this study, we developed a nomogram based on the platelet-albumin-bilirubin (PALBI) score to predict recurrence-free survival (RFS) after curative resection in alpha-fetoprotein (AFP)-negative (≤20 ng/mL) hepatocellular carcinoma (HCC) patients. Patients and Methods: A total of 194 pathologically confirmed AFP-negative HCC patients were retrospectively analyzed. Univariate and multivariate Cox regression analyses were performed to screen the independent risk factors associated with RFS, and a nomogram prediction model for RFS was established according to the independent risk factors. The receiver operating characteristic (ROC) curve and the C-index were used to evaluate the accuracy and the efficacy of the model prediction. The correction curve was used to assess the calibration of the prediction model, and decision curve analysis was performed to evaluate the clinical application value of the prediction model. Results: PALBI score, MVI, and tumor size were independent risk factors for postoperative tumor recurrence (P < 0.05). A nomogram prediction model based on the independent predictive factors was developed to predict RFS, and it achieved a good C-index of 0.704 with an area under the ROC curve of 0.661 and the sensitivity was 73.2%. Patients with AFP-negative HCC could be divided into the high-risk group or the low-risk group by the risk score calculated by the nomogram, and there was a significant difference in RFS between the two groups (P < 0.05). Decision curve analysis (DCA) showed that the nomogram increased the net benefit in predicting the recurrence of AFP-negative HCC and exhibited a wider range of threshold probabilities than the independent risk factors (PALBI score, MVI, and tumor size) by risk stratification. Conclusion: The nomogram based on the PALBI score can predict RFS after curative resection in AFP-negative HCC patients and can help clinicians to screen out high-risk patients for early intervention.

11.
Curr Cancer Drug Targets ; 23(3): 211-221, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36056860

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the leading cause of cancer-related deaths globally. This study aimed to provide a comprehensive investigation to screen and identify biomarkers for predicting HCC. METHODS: Firstly, the bioinformatics technique was applied to screen potential HCC-related genes, and the relationships between BZW2, CDT1, IVD expression and survival rate and clinicopathological factors were assessed. Afterward, qRT-PCR, western blot and immunohistochemistry were employed to validate the expression of BZW2, CDT1, and IVD in clinical resected cancer specimens. Furthermore, in vitro assays, cell cycle, apoptosis, colony formation and scratch experiments were performed to detect the effects of si-BZW2, si-CDT1 and oe-IVD in HCC cells. In vivo experiments, tumor volume and weight were measured to assess the anti-tumor effect of si-BZW2, si-CDT1 and oe-IVD in HCCtumor- bearing mice. RESULTS: Bioinformatics analysis indicated that HCC patients with high expression of BZW2, CDT1 and low expression of IVD have a poor prognosis and unfavorable clinicopathological factors. Similarly, clinical sample analysis revealed that BZW2 and CDT1 expression were increased while IVD expression was decreased in HCC tissues. Meanwhile, in vitro experiments found that si-BZW2, si- CDT1 and oe-IVD promoted apoptosis and inhibited the colony formation and migration of HCC cells. As expected, in vivo experiments demonstrated that si-BZW2, si-CDT1 and oe-IVD could inhibit tumor growth. CONCLUSION: Increased BZW2, CDT1 levels, and decreased IVD levels could act as biomarkers for predicting HCC. Furthermore, targeting BZW2, CDT1, and IVD may offer a new approach to treat HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Prognóstico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Apoptose/genética
12.
Chemistry ; 29(2): e202202774, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36193859

RESUMO

Manganese-catalyzed hydrogenation reactions have aroused widespread interest in recent years. Among the catalytic systems described, especially PNP- and NNP-Mn pincer catalysts have been reported for the hydrogenation of aldehydes, ketones, nitriles, aldimines and esters. Furthermore, NNP-Mn pincer compounds are efficient catalysts for the hydrogenolysis of less reactive amides, ureas, carbonates, and carbamates. Herein, the synthesis and application of specific imidazolylaminophosphine ligands and the corresponding Mn pincer complexes are described. These new catalysts have been characterized and studied by a combination of experimental and theoretical investigations, and their catalytic activities have been tested in several hydrogenation reactions with good to excellent performance. Especially, the reduction of N-heterocycles can be performed under very mild conditions.

13.
Cardiovasc Diabetol ; 21(1): 271, 2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36471410

RESUMO

BACKGROUND: Diabetes was commonly seen in chronic total occlusion (CTO) patients but data regarding the impact of successful percutaneous coronary intervention (PCI) on clinical outcome of CTO patients with diabetes was controversial. And importantly, no studies have compared quality of life (QOL) after CTO-PCI in patients with and without diabetes. METHODS: Consecutive patients undergoing elective CTO-PCI were prospectively enrolled from Apr. 2018 to May 2021. Patients were subdivided into 2 groups: Diabetes and No Diabetes. Detailed baseline characteristics, assessment of symptoms and QOL, angiographic and procedural details, in-hospital complications, and 1 month and 1 year follow-up data were collected. These data were analyzed accordingly for risk predictors of clinical outcome in patients who have diabetes and received successful CTO-PCI. RESULTS: A total of 1076 patients underwent CTO-PCI attempts. Diabetes was present in 374 (34.76%) patients, who had more hypertension, previous PCI and stroke. Regarding the coronary lesions, diabetic patients suffered more LCX lesion, multivessel disease, number of lesions per patient, blunt stump, calcification and higher J-CTO score (p < 0.05). In-hospital major adverse cardiac event (MACE) (4.13% vs. 5.35%; p = 0.362) was similar in the two groups. At 1 month and 1 year follow-up after successful CTO-PCI, the incidence of MACE and all-cause mortality were also similar in the two groups (p > 0.05). Number of lesions per patient was an independent risk factor of MACE and all-cause mortality (p < 0.001) 1 year after successful CTO-PCI. Symptom and QOL were markedly improved regardless of diabetes both at 1 month and 1 year follow-up, and importantly, patients with diabetes showed similar degrees of improvement to those without diabetes (P > 0.05). CONCLUSIONS: Successful CTO-PCI could represent an effective strategy improving clinical outcome, symptoms and QOL in CTO patients with diabetes.


Assuntos
Oclusão Coronária , Diabetes Mellitus , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Oclusão Coronária/diagnóstico por imagem , Oclusão Coronária/cirurgia , Qualidade de Vida , Angiografia Coronária , Resultado do Tratamento , Fatores de Risco , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/etiologia , Doença Crônica , Sistema de Registros
14.
J Phys Chem Lett ; 13(41): 9618-9631, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36214484

RESUMO

Since the first optical detection of single molecules in 1989, single-molecule spectroscopy has developed rapidly and been widely applied in many areas. However, the vast majority of matter is extremely inefficient at emitting photons in our physical world, which seriously limits the applications of optical methods based on photoluminescence. In addition to indirect detection by fluorescence labeling, many efforts have been made to directly image nonfluorescent matter at the single-particle or single-molecule level in different ways based on the absorption or scattering interaction between light and matter. Herein, we review five popular methods for imaging nonfluorescent particles/molecules, including dark-field microscopy (DFM), surface plasmon resonance microscopy (SPRM), surface enhanced Raman microscopy (SERM), interferometric scattering microscopy (iSCAT), and photothermal microscopy (PTM). After summarizing the principles and applications of these methods, we compare the advantages and disadvantages of each method and describe further potential development and applications.


Assuntos
Nanotecnologia , Moduladores Seletivos de Receptor Estrogênico , Ressonância de Plasmônio de Superfície/métodos , Microscopia/métodos , Fótons
15.
Nat Commun ; 13(1): 3330, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35680880

RESUMO

Sensitive detection of local acoustic vibrations at the nanometer scale has promising potential applications involving miniaturized devices in many areas, such as geological exploration, military reconnaissance, and ultrasound imaging. However, sensitive detection of weak acoustic signals with high spatial resolution at room temperature has become a major challenge. Here, we report a nanometer-scale system for acoustic detection with a single molecule as a probe based on minute variations of its distance to the surface of a plasmonic gold nanorod. This system can extract the frequency and amplitude of acoustic vibrations with experimental and theoretical sensitivities of 10 pm Hz-1/2 and 10 fm Hz-1/2, respectively. This approach provides a strategy for the optical detection of acoustic waves based on molecular spectroscopy without electromagnetic interference. Moreover, such a small nano-acoustic detector with 40-nm size can be employed to monitor acoustic vibrations or read out the quantum states of nanomechanical devices.


Assuntos
Ressonância de Plasmônio de Superfície , Vibração , Acústica , Nanotecnologia/métodos , Ressonância de Plasmônio de Superfície/métodos , Temperatura
16.
Light Sci Appl ; 11(1): 172, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35668065

RESUMO

Due to the complex core-shell structure and variety of surface functional groups, the photoluminescence (PL) mechanism of carbon dots (CDs) remain unclear. o-Phenylenediamine (oPD), as one of the most common precursors for preparing red emissive CDs, has been extensively studied. Interestingly, most of the red emission CDs based on oPD have similar PL emission characteristics. Herein, we prepared six different oPD-based CDs and found that they had almost the same PL emission and absorption spectra after purification. Structural and spectral characterization indicated that they had similar carbon core structures but different surface polymer shells. Furthermore, single-molecule PL spectroscopy confirmed that the multi-modal emission of those CDs originated from the transitions of different vibrational energy levels of the same PL center in the carbon core. In addition, the phenomenon of "spectral splitting" of single-particle CDs was observed at low temperature, which confirmed these oPD-based CDs were unique materials with properties of both organic molecules and quantum dots. Finally, theoretical calculations revealed their potential polymerization mode and carbon core structure. Moreover, we proposed the PL mechanism of red-emitting CDs based on oPD precursors; that is, the carbon core regulates the PL emission, and the polymer shell regulates the PL intensity. Our work resolves the controversy on the PL mechanism of oPD-based red CDs. These findings provide a general guide for the mechanism exploration and structural analysis of other types of CDs.

17.
Dalton Trans ; 51(12): 4869-4877, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35258062

RESUMO

Two novel manganese coordination polymers [Mn2(µ2-bcpb)(µ4-bcpb)(2,2'-bipy)2]n (1) and [Mn2(µ3-bcpb)2(2,2'-bipy)2(H2O)]n (2) (H2bcpb = 1,4-bis(2'-carboxylato phenoxy)-benzene; 2,2'-bipy = 2,2'-bipyridine), have been synthesized successfully from the same reactants. This unusual selectivity was corroborated by X-ray powder diffraction. Single crystal X-ray diffraction analysis of complex 1 reveals that neighboring Mn(II) ions are linked via two bcpb2- anions to form a dinuclear Mn(II) subunit [Mn2(µ1,1-COO)2]2+ with a Mn⋯Mn distance of 3.3758 (6) Å. And π⋯π interactions between aromatic rings of the bcpb2- and 2,2'-bipy ligands stabilize the two-dimensional extended coordination network with the unprecedented Schläfli symbols {4·62}2{42·62·82}. In the [Mn2(µ1,3-COO)2]2+ subunit of 2, two linking bcpb2- ligands subtend an interaction distance of 4.4048(6) Å. Intermolecular O-H⋯O hydrogen bonds involving oxygen atoms of carboxylic acid and coordinated water molecules connect adjacent 1D chain molecules into a 2D network. Experimental temperature-dependent magnetic susceptibility measurements and spin density analyses by DFT disclose that compounds 1 and 2 display different magnetic properties.

18.
Commun Chem ; 5(1): 1, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36697780

RESUMO

Non-spherical distributions of ligand atoms in coordination complexes are generally unfavorable due to higher repulsion than for spherical distributions. To the best of our knowledge, non-spherical heptagonal bipyramidal nonacoordination is hitherto unreported, because of extremely high repulsion among seven equatorial ligand atoms. Herein, we report the computational prediction of such nonacoordination, which is constructed by the synergetic coordination of an equatorial hepta-dentate centripetal ligand (B7O7) and two axial mono-dentate ligands (-BO) in the gear-like mono-anionic complexes [OB-M©B7O7-BO]- (M = Fe, Ru, Os). The high repulsion among seven equatorial ligand B atoms has been compensated by the strong B-O bonding. These complexes are the dynamically stable (up to 1500 K) global energy minima with the HOMO-LUMO gaps of 7.15 to 7.42 eV and first vertical detachment energies of 6.14 to 6.66 eV (being very high for anions), suggesting their high probability for experimental realization in both gas-phase and condensed phases. The high stability stems geometrically from the surrounded outer-shell oxygen atoms and electronically from meeting the 18e rule as well as possessing the σ + π + δ triple aromaticity. Remarkably, the ligand-metal interactions are governed not by the familiar donation and backdonation interactions, but by the electrostatic interactions and electron-sharing bonding.

19.
Front Cardiovasc Med ; 9: 1019688, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36620621

RESUMO

Background: A low estimated glomerular filtration rate (eGFR <90 mL/min/1.73 m2) is widely recognized as a risk factor for major adverse cardiac events (MACE) after percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). However, the impact of successful CTO-PCI on quality of life (QOL) of patients with low eGFR remains unknown. Objectives: The aim of this prospective study was to assess the QOL of CTO patients with low eGFR after successful PCI. Methods: Consecutive patients undergoing elective CTO-PCI were prospectively enrolled and subdivided into four groups: eGFR ≥90 mL/min/1.73 m2 (n = 410), 90 > eGFR ≥ 60 mL/min/1.73 m2 (n = 482), 60 > eGFR ≥ 30 mL/min/1.73 m2 (n = 161), and eGFR <30 mL/min/1.73 m2 (n = 23). The primary outcomes included QOL, as assessed with the European Quality of Life-5 Dimensions (EQ-5D) questionnaire, and symptoms, as assessed with the Rose Dyspnea Scale (RDS) and Seattle Angina Questionnaire (SAQ), at 1 month and 1 year after successful PCI. Results: With the decline of eGFR, CTO patients were more likely to present with comorbidities of hypertension, diabetes, hyperuricemia, and previous stroke, in addition to lower hemoglobin levels and left ventricular ejection fraction (p < 0.05). Low eGFR was associated with greater incidences of in-hospital pericardiocentesis, major bleeding, acute renal failure, and subcutaneous hematoma, but not in-hospital MACE (p < 0.05). Symptoms of dyspnea and angina were alleviated in all CTO patients with eGFR ≥30 mL/min/1.73 m2 at 1 month and 1 year after successful CTO-PCI, but only at 1 month for those with eGFR <30 mL/min/1.73 m2 (p < 0.01). Importantly, QOL was markedly improved at 1 month and 1 year after successful PCI (p < 0.01), notably at a similar degree between patients with low eGFR and those with normal eGFR (p > 0.05). Conclusion: Successful PCI effectively improved symptoms and QOL of CTO patients with low eGFR.

20.
J Phys Chem Lett ; 12(35): 8614-8620, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34469165

RESUMO

Carbon dots (CDs), as emerging luminescent nanomaterials, possess excellent but complex properties, and thus, they have attracted immense attention for their applications. Further practical application of CDs has been hindered by their limited photostability and photoluminescence intermittency. In this study, we demonstrated that an antioxidant (Trolox) can dramatically enhance the photostability and minimize the photoblinking of CDs without affecting their native spectral characteristics. Significant photoluminescence enhancement and stabilization were observed with the addition of Trolox in ensemble level. Meanwhile, strikingly stable emissions from individual CDs have been observed in the presence of Trolox in single-particle-level experiments. Our observations revealed that the charged state of CDs can be effectively recovered to a neutral state by Trolox via electron transfer. These results prove that the combination of antioxidants and CDs is a powerful means to improve their fluorescence robustness, which is crucial for applications that demand long-lived, nonblinking emission.

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