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1.
Inorg Chem ; 63(38): 17478-17487, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39229693

RESUMO

Metalo hydrogen-bonded organic frameworks (MHOFs) have received growing interest in designing crystalline functional materials. However, reports on bifunctional MHOFs showing magnetic and proton-conductive properties are extremely limited and their design is challenging. Herein, we investigated the magnetic and proton-conductive properties of two sulfonated CoHOF and MnHOF, {M(H2O)2(abs)2}n (M = Co2+ and Mn2+, Habs = 4-aminoazobenzene-4'-sulfonic anion), constructed by coordination chains. The supramolecular frameworks sustained by H bonds between -SO3- and coordinated water show directional ladder-type H bonds with hydrophilic nanochannels, leading to high proton conduction with exceptionally high conductivity around 10-2 S cm-1 at 100 °C under 97% relative humidity. In particular, the maximum σ value of CoHOF, 2.11 × 10-2 S cm-1, recorded the highest value among the reported proton-conducting materials showing slow magnetic relaxation. Meanwhile, the molecular structure of organosulfonate enables the magnetic isolation of high-spin Co2+ and Mn2+ centers in the frameworks. Magnetic measurements indicated that the MHOFs show field-induced single-ion magnet (SIM) properties, making these compounds rare magnetic-proton-conductive MHOFs. The work provides not only two unique MHOFs with SIM behavior and high proton conduction performance but also avenues for designing stable bifunctional MHOFs via a coordination chain approach.

2.
BMC Cardiovasc Disord ; 24(1): 338, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965474

RESUMO

BACKGROUND: The relationship between obstructive sleep apnea (OSA) and the occurrence of arrhythmias and heart rate variability (HRV) in hypertensive patients is not elucidated. Our study investigates the association between OSA, arrhythmias, and HRV in hypertensive patients. METHODS: We conducted a cross-sectional analysis involving hypertensive patients divided based on their apnea-hypopnea index (AHI) into two groups: the AHI ≤ 15 and the AHI > 15. All participants underwent polysomnography (PSG), 24-hour dynamic electrocardiography (DCG), cardiac Doppler ultrasound, and other relevant evaluations. RESULTS: The AHI > 15 group showed a significantly higher prevalence of frequent atrial premature beats and atrial tachycardia (P = 0.030 and P = 0.035, respectively) than the AHI ≤ 15 group. Time-domain analysis indicated that the standard deviation of normal-to-normal R-R intervals (SDNN) and the standard deviation of every 5-minute normal-to-normal R-R intervals (SDANN) were significantly higher in the AHI > 15 group (P = 0.020 and P = 0.033, respectively). Frequency domain analysis revealed that the low-frequency (LF), high-frequency (HF) components, and the LF/HF ratio were also significantly elevated in the AHI > 15 group (P < 0.001, P = 0.031, and P = 0.028, respectively). Furthermore, left atrial diameter (LAD) was significantly larger in the AHI > 15 group (P < 0.001). Both univariate and multivariable linear regression analyses confirmed a significant association between PSG-derived independent variables and the dependent HRV parameters SDNN, LF, and LF/HF ratio (F = 8.929, P < 0.001; F = 14.832, P < 0.001; F = 5.917, P = 0.016, respectively). CONCLUSIONS: Hypertensive patients with AHI > 15 are at an increased risk for atrial arrhythmias and left atrial dilation, with HRV significantly correlating with OSA severity.


Assuntos
Arritmias Cardíacas , Frequência Cardíaca , Hipertensão , Polissonografia , Apneia Obstrutiva do Sono , Humanos , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/complicações , Masculino , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Hipertensão/fisiopatologia , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/etiologia , Idoso , Fatores de Risco , Prevalência , Eletrocardiografia Ambulatorial , Adulto , Fatores de Tempo , Ecocardiografia Doppler , Complexos Atriais Prematuros/fisiopatologia , Complexos Atriais Prematuros/diagnóstico , Complexos Atriais Prematuros/epidemiologia , Medição de Risco , Índice de Gravidade de Doença
3.
Sleep Breath ; 28(3): 1251-1260, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38326691

RESUMO

BACKGROUND: Hypertension frequently coexists with obstructive sleep apnea (OSA), and their interplay substantially impacts the prognosis of affected individuals. Investigating the influence of OSA on blood pressure variability (BPV) and blood pressure load (BPL) in hypertensive patients has become a focal point of clinical research. METHODS: This cross-sectional study recruited hypertensive patients (n = 265) without discrimination and classified them into four groups based on their apnea-hypopnea index (AHI): control group (n = 40), AHI < 5; mild group (n = 74), 5 ≤ AHI ≤ 15; moderate group (n = 68), 15 < AHI ≤ 30; severe group (n = 83), AHI > 30. All participants underwent comprehensive assessments, including polysomnography (PSG) monitoring, 24-h ambulatory blood pressure (ABP) monitoring, cardiac Doppler ultrasound, and additional examinations when indicated. RESULTS: BPV and BPL exhibited significant elevations in the moderate and severe OSA groups compared to the control and mild OSA groups (P < 0.05). Moreover, interventricular septum thickness and left ventricular end-diastolic volume (LVEDV) demonstrated higher values in the moderate and severe OSA groups (P < 0.05). Multiple stepwise regression analysis identified noteworthy risk factors for elevated BPV in hypertensive patients with OSA, including AHI, maximum apnea time, total times of oxygen reduction, and mean time of apnea. CONCLUSION: Hypertensive patients with moderate to severe OSA exhibited substantially increased BPV and BPL. Moreover, BPV was correlated with AHI, maximum apnea time, total times of oxygen reduction, and mean time of apnea in hypertensive patients with OSA.


Assuntos
Pressão Sanguínea , Hipertensão , Polissonografia , Apneia Obstrutiva do Sono , Humanos , Apneia Obstrutiva do Sono/fisiopatologia , Hipertensão/fisiopatologia , Hipertensão/complicações , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Transversais , Pressão Sanguínea/fisiologia , Adulto , Monitorização Ambulatorial da Pressão Arterial , Idoso
4.
Exp Appl Acarol ; 92(3): 403-421, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38489086

RESUMO

Spider mites (Acari: Tetranychidae) are polyphagous pests of economic importance in agriculture, among which the two-spotted spider mite Tetranychus urticae Koch has spread widely worldwide as an invasive species, posing a serious threat to fruit tree production in China, including Beijing. The hawthorn spider mite, Amphitetranychus viennensis Zacher, is also a worldwide pest of fruit trees and woody ornamental plants. The cassava mite, Tetranychus truncatus Ehara, is mainly found in Asian countries, including China, Korea and Japan, and mainly affects fruit trees and agricultural crops. These three species of spider mites are widespread and serious fruit tree pests in Beijing. Rapid and accurate identification of spider mites is essential for effective pest and plant quarantine in Beijing orchard fields. The identification of spider mite species is difficult due to their limited morphological characteristics. Although the identification of insect and mite species based on PCR and real-time polymerase chain reaction TaqMan is becoming increasingly common, DNA extraction is difficult, expensive and time-consuming due to the minute size of spider mites. Therefore, the objective of this study was to establish a direct multiplex PCR method for the simultaneous identification of three common species of spider mites in orchards, A. viennensis, T. truncatus and T. urticae, to provide technical support for the differentiation of spider mite species and phytosanitary measures in orchards in Beijing. Based on the mitochondrial cytochrome c oxidase subunit I (COI) of the two-spotted spider mite and the cassava mite and the 18S gene sequence of the hawthorn spider mite as the amplification target, three pairs of specific primers were designed, and the primer concentrations were optimized to establish a direct multiplex PCR system for the rapid and accurate discrimination of the three spider mites without the need for DNA extraction and purification. The method showed a high sensitivity of 0.047 ng for T. truncatus and T. urticae DNA and 0.0002 ng for A. viennensis. This method eliminates the DNA extraction and sequencing procedures of spider mite samples, offers a possibility for rapid monitoring of multiple spider mites in an integrated microarray laboratory system, reducing the time and cost of leaf mite identification and quarantine monitoring in the field.


Assuntos
Reação em Cadeia da Polimerase Multiplex , Tetranychidae , Animais , Tetranychidae/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Pequim , Complexo IV da Cadeia de Transporte de Elétrons/genética
5.
Cell Tissue Res ; 391(1): 1-17, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36380098

RESUMO

Spinal cord injury (SCI) is a very serious clinical traumatic illness with a very high disability rate. It not only causes serious functional disorders below the injured segment, but also causes unimaginable economic burden to social development. Exosomes are nano-sized cellular communication carriers that exist stably in almost all organisms and cell types. Because of their capacity to transport proteins, lipids, and nucleic acids, they affect various physiological and pathological functions of recipient cells and parental cells. Autophagy is a process that relies on the lysosomal pathway to degrade cytoplasmic proteins and organelles and involves a variety of pathophysiological processes. Exosomes and autophagy play critical roles in cellular homeostasis following spinal cord injury. Presently, the coordination mechanism of exosomes and autophagy has attracted much attention in the early efficacy of spinal cord injury. In this review, we discussed the interaction of autophagy and exosomes from the perspective of molecular mechanisms, which might provide novel insights for the early therapeutic application of spinal cord injury.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Traumatismos da Medula Espinal , Humanos , Exossomos/metabolismo , Traumatismos da Medula Espinal/terapia , Autofagia , Neurônios/metabolismo , Células-Tronco Mesenquimais/metabolismo , Medula Espinal/patologia
6.
J Exp Bot ; 74(18): 5694-5708, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37490479

RESUMO

The mitochondrion is a semi-autonomous organelle that provides energy for cell activities through oxidative phosphorylation. In this study, we identified a defective kernel 66 (dek66)-mutant maize with defective kernels. We characterized a candidate gene, DEK66, encoding a ribosomal assembly factor located in mitochondria and possessing GTPase activity (which belongs to the ribosome biogenesis GTPase A family). In the dek66 mutant, impairment of mitochondrial structure and function led to the accumulation of reactive oxygen species and promoted programmed cell death in endosperm cells. Furthermore, the transcript levels of most of the key genes associated with nutrient storage, mitochondrial respiratory chain complex, and mitochondrial ribosomes in the dek66 mutant were significantly altered. Collectively, the results suggest that DEK66 is essential for the development of maize kernels by affecting mitochondrial function. This study provides a reference for understanding the impact of a mitochondrial ribosomal assembly factor in maize kernel development.


Assuntos
Proteínas de Plantas , Zea mays , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Zea mays/metabolismo , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Endosperma/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Regulação da Expressão Gênica de Plantas
7.
BMC Cancer ; 23(1): 72, 2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36670414

RESUMO

BACKGROUND & OBJECTIVE: "Anti-angiogenetic drugs plus chemotherapy" (anti-angio-chemo) and "immune checkpoint inhibitors plus chemotherapy" (ICI-chemo) are superior to traditional chemotherapy in the first-line treatment of patients with advanced non-small-cell lung cancer (NSCLC). However, in the absence of a direct comparison of ICI-chemo with anti-angio-chemo, the superior one between them has not been decided, and the benefit of adding anti-angiogenetic agents to ICI-chemo remains controversial. This study aimed to investigate the role of antiangiogenic agents for advanced NSCLC in the era of immunotherapy. METHODS: Eligible randomized controlled trials (RCTs) comparing chemotherapy versus therapeutic regimens involving ICIs or anti-angiogenetic drugs were included. Outcomes included progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and rate of grade 3-4 toxicity assessment. R-4.3.1 was utilized to perform the analysis. RESULTS: A total of 54 studies with a sample size of 25,046 were finally enrolled. "Atezolizumab + Bevacizumab + Chemotherapy" significantly improved the ORR compared with "Atezolizumab + Chemotherapy" (Odds ratio (OR) = 2.73, 95% confidence interval (CI): 1.27-5.87). The trend also favored "Atezolizumab + Bevacizumab + Chemotherapy" in PFS and OS (hazard ratio (HR) = 0.71, 95% CI: 0.39-1.31; HR = 0.94, 95% CI: 0.77-1.16, respectively). In addition, "Pembrolizumab + Chemotherapy" and "Camrelizumab + Chemotherapy" significantly prolonged the PFS compared to "Bevacizumab + Chemotherapy" (HR = 0.65, 95% CI: 0.46-0.92; HR = 0.63, 95% CI: 0.41-0.97; respectively). Meanwhile, "Pembrolizumab + Chemotherapy" and "Sintilimab + Chemotherapy" yielded more OS benefits than "Bevacizumab + Chemotherapy" (HR = 0.69, 95% CI: 0.56-0.83; HR = 0.64, 95%CI: 0.46-0.91; respectively). Scheme between "Atezolizumab + Bevacizumab + Chemotherapy" and "Atezolizumab + Chemotherapy" made no significant difference (OR = 1.18, 95%CI: 0.56-2.42) concerning the rate of grade 3-4 toxicity. It seemed that ICI-chemo yielded more improvement in quality-adjusted life-year (QALY) than "Bevacizumab + Chemotherapy" in cost-effectiveness analysis. CONCLUSION: Our results suggest that ICI-chemo is associated with potentially longer survival, better cost-effectiveness outcomes, and comparable safety profiles than anti-angio-chemo. Also, adding bevacizumab to ICI-chemo seemed to provide additional therapeutic benefits without adding treatment burden. Our findings would supplement the current standard of care and help the design of future clinical trials for the first-line treatment of patients with advanced NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Inibidores da Angiogênese/efeitos adversos , Bevacizumab/uso terapêutico , Imunoterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
8.
Inorg Chem ; 62(30): 11932-11942, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37452753

RESUMO

A series of trimetallic complexes [FeIII(µ-L)(py)]2MII(py)n (n = 2, MII = MnII, 1; FeII, 2; CoII, 3; ZnII, 4; n = 3, MII = CdII, 5) with a new bridging ligand L4- (deprotonated 1,2-N1,N2-bis(2-mercaptoanil) oxalimidic acid) were synthesized and fully characterized by elemental analysis, single-crystal X-ray crystallography, IR, and Mössbauer spectra. Interestingly, the bridging ligand was obtained by oxidative addition of the (gma•)3- ligand from the mononuclear precursor Fe(gma)py (gma = glyoxal-bis(2-mercaptoanil)). In the obtained complexes, the bridging ligand L4- coordinates to the terminal FeIII ions (intermediate-spin with SFe = 3/2) by the N, S atoms, and coordinate to the central metal MII ion by the four O atoms. The resonance structure of the bridging ligand can be described as the two 4π-electron delocalized systems connected by one single-bond (C1-C2), which is different from the electronic structure of the precursor Fe(gma)py. Remarkably, the magnetic coupling interaction can be regulated through the central metal. The ferromagnetic coupling constant J gradually decreases as MII changes from FeII to CoII and MnII, while the paramagnetic behaviors are presented when MII = ZnII and CdII, confirmed by the magnetic susceptibility measurements and further supported by using the PHI program. Furthermore, the bridging ligand to the terminal FeIII charge transfer (LMCT) transitions emerged in all complexes but the central FeII to terminal FeIII charge transfer (MMCT) only presented in complex 2, strongly supported by the UV/vis-NIR electronic spectra and TDDFT calculations.

9.
Neoplasma ; 70(2): 260-271, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37226933

RESUMO

Metabolic reprogramming is a common feature of glioblastoma (GBM) progression and metastasis. Altered lipid metabolism is one of the most prominent metabolic alterations in cancer. Understanding the links between phospholipid remodeling and GBM tumorigenesis may help develop new anticancer strategies and improve treatments to overcome drug resistance. We used metabolomic and transcriptomic analyses to systematically investigate metabolic and molecular changes in low-grade glioma (LGG) and GBM. We then re-established the reprogrammed metabolic flux and membrane lipid composition in GBM based on metabolomic and transcriptomic analyses. By inhibiting Aurora A kinase via RNA interference (RNAi) and inhibitor treatment, we investigated the effect of Aurora A kinase on phospholipid reprogramming LPCAT1 enzyme expression and GBM cell proliferation in vitro and in vivo. We found that GBM displayed aberrant glycerophospholipid and glycerolipid metabolism compared with LGG. Metabolic profiling indicated that fatty acid synthesis and uptake for phospholipid synthesis were significantly increased in GBM compared to LGG. The unsaturated phosphatidylcholine (PC) and phosphatidylethanolamine (PE) levels were significantly decreased in GBM compared to LGG. The expression level of LPCAT1, which is required for the synthesis of saturated PC and PE, was upregulated in GBM, and the expression of LPCAT4, which is required for the synthesis of unsaturated PC and PE, was downregulated in GBM. Notably, the inhibition of Aurora A kinase by shRNA knockdown and treatment with Aurora A kinase inhibitors such as Alisertib, AMG900, or AT9283 upregulated LPCAT1 mRNA and protein expression in vitro. In vivo, the inhibition of Aurora A kinase with Alisertib increased LPCAT1 protein expression. Phospholipid remodeling and a reduction in unsaturated membrane lipid components were found in GBM. Aurora A kinase inhibition increased LPCAT1 expression and suppressed GBM cell proliferation. The combination of Aurora kinase inhibition with LPCAT1 inhibition may exert promising synergistic effects on GBM.


Assuntos
Glioblastoma , Glioma , Humanos , Glioblastoma/tratamento farmacológico , Fosfolipídeos , Aurora Quinase A , Lipídeos de Membrana , 1-Acilglicerofosfocolina O-Aciltransferase
10.
Sensors (Basel) ; 23(8)2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37112366

RESUMO

The convolution module in Conformer is capable of providing translationally invariant convolution in time and space. This is often used in Mandarin recognition tasks to address the diversity of speech signals by treating the time-frequency maps of speech signals as images. However, convolutional networks are more effective in local feature modeling, while dialect recognition tasks require the extraction of a long sequence of contextual information features; therefore, the SE-Conformer-TCN is proposed in this paper. By embedding the squeeze-excitation block into the Conformer, the interdependence between the features of channels can be explicitly modeled to enhance the model's ability to select interrelated channels, thus increasing the weight of effective speech spectrogram features and decreasing the weight of ineffective or less effective feature maps. The multi-head self-attention and temporal convolutional network is built in parallel, in which the dilated causal convolutions module can cover the input time series by increasing the expansion factor and convolutional kernel to capture the location information implied between the sequences and enhance the model's access to location information. Experiments on four public datasets demonstrate that the proposed model has a higher performance for the recognition of Mandarin with an accent, and the sentence error rate is reduced by 2.1% compared to the Conformer, with only 4.9% character error rate.


Assuntos
Percepção da Fala , Fala , Idioma , Algoritmos , Reconhecimento Psicológico
11.
Am J Respir Cell Mol Biol ; 66(3): 283-292, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34851809

RESUMO

Asthma is a common, complex disease with apparent genetic predispositions, and previous genome-wide association studies suggest that rs1295686 within the IL13 (IL-13) gene is significantly associated with asthma. Analysis of the data provided by the 1,000 Genomes Project indicated an additional four SNPs in nearly complete linkage disequilibrium with rs1295686 in White people. However, the causal SNPs and the associated mechanism remain unclear. To investigate this issue, functional genomics approaches were utilized to analyze the functions of these SNPs. Dual-luciferase assays indicated that the functional SNP is not rs1295686 but a haplotype consisting of three other SNPs: rs1295685, rs848, and rs847. Through chromosome conformation capture, it was found that the enhancer containing the three functional SNPs interacts with the promoter of TH2LCRR (T helper type 2 locus control region associated RNA), a recently identified long noncoding RNA. RNA-seq data analysis indicated that TH2LCRR expression is significantly increased in patients with asthma and is dependent on the genotype at this locus, indicating that TH2LCRR is a novel susceptibility gene for asthma and that these SNPs confer asthma risk by regulating TH2LCRR expression. By chromatin immunoprecipitation, the related transcription factors that bind in the region surrounding these three SNPs were identified, and their interactions were investigated by functional genomics approaches. Our effort identified a novel mechanism through which genetic variations at this locus could influence asthma susceptibility.


Assuntos
Asma , Estudo de Associação Genômica Ampla , RNA/genética , Asma/genética , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas
12.
J Transl Med ; 20(1): 433, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36180876

RESUMO

BACKGROUND: The immune checkpoint inhibitors (ICIs) combined with other therapeutic strategies have shown exciting results in various malignancies, and ICIs have now become the gold standard for current cancer treatment. In several preclinical and clinical investigations, ablation coupled with immunotherapy has proved to be quite effective. Our previous studies have shown that ablation coupled with ICI is a potential anti-cancer regimen for colorectal cancer liver metastases (CRLM). Furthermore, we have reported that following microwave ablation (MWA), the expression of LAG3 is up-regulated in tumor microenvironment (TME), indicating that LAG3 is implicated in the regulation of immunosuppressive immune response, and combination therapy of MWA and LAG3 blockade can serve as a promising therapeutic strategy against cancer. METHODS: The expression of LAG3 was investigated in this study utilizing a preclinical mouse model treated with MWA. Moreover, we monitored the tumor development and survival in mice to assess the anti-cancer effects of MWA alone or in combination with LAG3 blockade. Flow cytometry was also used to phenotype the tumor-infiltrating lymphocytes (TILs) and CD8+ T cell effector molecules. We finally analyzed the single-cell RNA sequencing (scRNA-seq) data of infiltrating CD45+ immune cells in the tumors from the MWA alone and MWA combined with LAG3 blockade groups. RESULTS: After MWA, the expression of LAG3 was up-regulated on sub-populations of TILs, and introducing LAG3 blockade to MWA postponed tumor development and extended survival in the MC38 tumor model. Flow cytometry and scRNA-seq revealed that LAG3 blockade in combination with MWA markedly boosted the proliferation and the function of CD8+ TILs, leading to altered myeloid cells in the TME. CONCLUSION: Combination therapy of LAG3 blockade and MWA was a unique therapeutic regimen for some solid tumors, and such combination therapy might reprogram the TME to an anti-tumor manner.


Assuntos
Neoplasias Hepáticas , Micro-Ondas , Animais , Linfócitos T CD8-Positivos , Inibidores de Checkpoint Imunológico , Linfócitos do Interstício Tumoral , Camundongos , Micro-Ondas/uso terapêutico , Microambiente Tumoral
13.
Chemistry ; 28(34): e202104486, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35347776

RESUMO

To investigate the effects of cis/trans-configuration of the cyanidometal bridge and the electron donating ability of the auxiliary ligand on the cyanidometal bridge on metal to metal charge transfer (MMCT) in cyanidometal-bridged mixed valence compounds, two groups of trinuclear cyanidometal-bridged compounds cis/trans-[Cp(dppe)Fe(µ-NC)Ru(4,4'-dmbpy)2 (µ-CN)Fe(dppe)Cp][PF6 ]n (n=2 (cis/trans-1[PF6 ]2 ), 3 (cis/trans-1[PF6 ]3 ), 4 (cis/trans-1[PF6 ]4 )) and cis/trans-[Cp(dppe)Fe(µ-NC)Ru(bpy)2 (µ-CN)Fe(dppe)Cp][PF6 ]3 (cis/trans-2[PF6 ]3 ) were synthesized and fully characterized. The experimental results indicate that for these one- and two-electron oxidation mixed valence compounds, the trans-configuration compounds are more beneficial for MMCT than the cis-configuration compounds, and increasing the electron donating ability of the auxiliary ligand on the cyanidometal bridge is also conductive to MMCT. Moreover, compounds cis/trans-1[PF6 ]n (n=3, 4) and cis/trans-2[PF6 ]3 belong to localized compounds by analyzing the experimental characterization results, supported by the TDDFT calculations.

14.
Inorg Chem ; 61(8): 3754-3762, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35167748

RESUMO

A unique hydrogen-bonded organic-inorganic framework (HOIF) constructed from a mononuclear cobalt(II) complex, [Co(MCA)2·(H2O)2] (HMCA = 4-imidazolecarboxylic acid), via multiple hydrogen-bonding interactions was synthesized and structurally characterized. The Co(II) center in the HOIF features a highly distorted octahedral coordination environment. Remarkably, the CoII HOIF showed permanent porosity with superior stability as established by combined thermogravimetric analysis (TGA), variable-temperature infrared spectra (IR), variable-temperature powder X-ray diffraction data (PXRD), and a CO2 isotherm. Structural studies reveal that short multiple hydrogen bonds should be responsible for the superior thermal and chemical stability of a HIOF. Magnetic investigations reveal the large easy-plane magnetic anisotropy of the Co2+ ions with the fitted D values being 22.1 (magnetic susceptibility and magnetization data) and 29.1 cm-1 (reduced magnetization data). In addition, the HOIF exhibits field-induced slow magnetic relaxation at low temperature with an effective energy barrier of Ueff = 45.2 cm-1, indicative of a hydrogen-bonded framework single-ion magnet of the compound. The origin of the significant magnetic anisotropy of the complex was also understood from computational studies. In addition, BS-DFT calculations indicate that the superexchange interactions between the neighboring CoII ions are non-negligible antiferromagnetism with JCo-Co = -0.5 cm-1. The foregoing results provide not only a carboxylate-imidazole ligand approach toward a stable HOIF but also a promising way to build a robust single-ion magnet via hydrogen-bond interactions.

15.
Inorg Chem ; 61(15): 5855-5860, 2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35377631

RESUMO

The incorporation of two different cyanide building blocks of [(TpR)FeIII(CN)3]- and [AuI(CN)2]- into one molecule afforded a novel hexanuclear [FeIII2FeII2AuI2] complex (1·2Et2O), in which the cyanide-bridged [FeIII2FeII2] square was further grafted by two [AuI(CN)2]- fragments as long arms in syn orientations. Complex 1·2Et2O undergoes a gradual spin crossover (SCO) ffrom low-spin (LS) to high-spin (HS) state for the Fe(II) centers upon desolvation. Remarkably, its desolvated phase (1) exhibits a reversible but atypical two-step (sharp-gradual) SCO behavior with considerable hysteresis (21 K). Variable-temperature single-crystal X-ray structural studies reveal that the hysteretic spin transition takes place synchronously with the concerted displacive motions of the molecules, representing another rare example including multistep and hysteretic spin transitions due to the synergetic SCO and structural phase transition.

16.
BMC Pregnancy Childbirth ; 22(1): 538, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35787798

RESUMO

BACKGROUND: Perinatal complications are common burdens for neonates born from mother with pPROM. Physicians and parents sometimes need to make critical decisions about neonatal care with short- and long-term implications on infant's health and families and it is important to predict severe neonatal outcomes with high accuracy. METHODS: The study was based on our prospective study on 1001 preterm infants born from mother with pPROM from August 1, 2017, to March 31, 2018 in three hospitals in China. Multivariable logistic regression analysis was applied to build a predicting model incorporating obstetric and neonatal characteristics available within the first day of NICU admission. We used enhanced bootstrap resampling for internal validation. RESULTS: One thousand one-hundred pregnancies with PROM at preterm with a single fetus were included in our study. SNO was diagnosed in 180 (17.98%) neonates. On multivariate analysis of the primary cohort, independent factors for SNO were respiratory support on the first day,, surfactant on day 1, and birth weight, which were selected into the nomogram. The model displayed good discrimination with a C-index of 0.838 (95%CI, 0.802-0.874) and good calibration performance. High C-index value of 0.835 could still be reached in the internal validation and the calibration curve showed good agreement. Decision curve analysis showed if the threshold is > 15%, using our model would achieve higher net benefit than model with birthweight as the only one predictor. CONCLUSION: Variables available on the first day in NICU including respiratory support on the first day, the use of surfactant on the first day and birthweight could be used to predict the risk of SNO in infants born from mother with pPROM with good discrimination and calibration performance.


Assuntos
Recém-Nascido Prematuro , Mães , Peso ao Nascer , Feminino , Ruptura Prematura de Membranas Fetais , Humanos , Lactente , Recém-Nascido , Gravidez , Estudos Prospectivos , Tensoativos
17.
Planta ; 254(3): 58, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34426887

RESUMO

MAIN CONCLUSION: Arabidopsis AtPRP17, a homolog of yeast splicing factor gene PRP17, is expressed in siliques and embryos and functions in embryo development via regulating embryonic patterning. Yeast splicing factor PRP17/CDC40 is essential for cell growth through involvement in cell cycle regulation. Arabidopsis genome encodes a homolog of PRP17, AtPRP17; however, its function in Arabidopsis development is unknown. This study showed that AtPRP17 was highly expressed in siliques and embryos, and the protein was localized in the nucleus. The loss-of-function mutation of AtPRP17 led to shrunken seeds in Arabidopsis mature siliques. Further analysis revealed that the defective mature seeds of the mutant resulted from abnormal embryos with shriveled cotyledons, unequal cotyledons, swollen and shortened hypocotyls, or shortened radicles. During embryogenesis, mutant embryos showed delayed development and defective patterning of the apical and base domains, such as inhibited cotyledons and disorganized quiescent center cells and columella. Our results suggested that AtPRP17 functions in Arabidopsis embryo development via regulating embryonic patterning.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cotilédone/genética , Desenvolvimento Embrionário , Hipocótilo
18.
Chemistry ; 27(43): 11183-11194, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-33939198

RESUMO

The synthesis and characterization of Class II-III mixed valence complexes have been an interesting topic due to their special intermediate behaviour between localized and delocalized mixed valence complexes. To investigate the influence of the isocyanidometal bridge on metal-to-metal charge transfer (MMCT) properties, a family of new isocyanidometal-bridged complexes and their one-electron oxidation products cis-[Cp(dppe)Fe-CN-Ru(L)2 -NC-Fe(dppe)Cp][PF6 ]n (n=2, 3) (Cp=1,3-cyclopentadiene, dppe=1,2-bis(diphenylphosphino)ethane, L=2,2'-bipyridine (bpy, 1[PF6 ]n ), 5,5'-dimethyl-2,2'-bipyridyl (5,5'-dmbpy, 2[PF6 ]n ) and 4,4'-dimethyl-2,2'-bipyridyl (4,4'-dmbpy, 3[PF6 ]n )) have been synthesized and fully characterized. The experimental results suggest that all the one-electron oxidation products may belong to Class II-III mixed valence complexes, supported by TDDFT calculations. With the change of the substituents of the bipyridyl ligand on the Ru centre from H, 5,5'-dimethyl to 4,4'-dimethyl, the energy of MMCT for the one-electron oxidation complexes changes in the order: 13+ <23+ <33+ , and that for the two-electron oxidation complexes decreases in the order 14+ >34+ >24+ . The potential splitting (ΔE1/2 (2)) between the two terminal Fe centres for N[PF6 ]2 are the largest potential splitting for the cyanido-bridged complexes reported so far. This work shows that the smaller potential difference between the bridging and the terminal metal centres would result in the more delocalized mixed valence complex.

19.
Angew Chem Int Ed Engl ; 60(9): 4804-4814, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33226727

RESUMO

Mixed-valence compounds with the iso-cyanidometal-ligand bridge in different oxidation states are used as models for the investigation of the electron-transfer process. We synthesized a series of trimetallic isocyanidometal-bridged compounds with [Fe-CN-Ru-NC-Fe]n+ (n=2-4), in which the one-electron oxidation product (N3+ ) and two-electron oxidation product (N4+ ) compounds possess an isocyanidometal bridge whose energy is, respectively lower and slightly higher than the terminal metal centers energies. For the N3+ compounds, the bridge state (FeII -RuIII -FeII ) and mixed-valence states (FeIII -RuII -FeII or FeII -RuII -FeIII ) could be simultaneously observed on the IR timescale. For the N4+ compounds, as the donor becomes stronger the electron transfer bridge excited state (FeIII -RuII -FeIII ) becomes more and more stable, and even becomes ground state due to the strong electronic coupling between Fe and Ru.

20.
J Cardiovasc Pharmacol ; 76(2): 246-254, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32433360

RESUMO

Cardiac hypertrophy causes heart failure and is associated with hyperglycemia in patients with diabetes mellitus. Mibefradil, which acts as a T-type calcium channel blocker, exerts beneficial effects in patients with heart failure. In this study, we explored the effects and mechanism of mibefradil on high-glucose-induced cardiac hypertrophy in H9c2 cells. H9c2 cells were incubated in a high-glucose medium and then treated with different concentrations of mibefradil in the presence or absence of the Akt inhibitor MK2206 or mTOR inhibitor rapamycin. Cell size was evaluated through immunofluorescence, and mRNA expression of cardiac hypertrophy markers (atrial natriuretic peptide, brain natriuretic peptide, and ß-myosin heavy chain) was assessed by using quantitative real-time polymerase chain reaction. Changes in the expression of p-PI3K, p-Akt, and p-mTOR were evaluated using Western blotting, and autophagosome formation was detected using transmission electron microscopy. Our results indicate that mibefradil reduced the size of H9c2 cells, decreased mRNA expression of atrial natriuretic peptide, brain natriuretic peptide, and ß-myosin heavy chain, and decreased the level of autophagic flux. However, MK2206 and rapamycin induced autophagy and reversed the effects of mibefradil on high-glucose-induced H9c2 cells. In conclusion, mibefradil ameliorated high-glucose-induced cardiac hypertrophy by activating the PI3K/Akt/mTOR pathway and inhibiting excessive autophagy. Our study shows that mibefradil can be used therapeutically to ameliorate cardiac hypertrophy in patients with diabetes mellitus.


Assuntos
Autofagia/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Cardiomegalia/prevenção & controle , Glucose/toxicidade , Mibefradil/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Fator Natriurético Atrial/genética , Fator Natriurético Atrial/metabolismo , Cardiomegalia/induzido quimicamente , Cardiomegalia/enzimologia , Cardiomegalia/patologia , Linhagem Celular , Tamanho Celular/efeitos dos fármacos , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/ultraestrutura , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , Peptídeo Natriurético Encefálico/genética , Peptídeo Natriurético Encefálico/metabolismo , Fosforilação , Ratos , Transdução de Sinais
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