Context
The reaction between Na and HF is a typical harpooning reaction which is of great interest due to its significance in understanding the elementary chemical reaction kinetics. This work aims ...to investigate the detailed reaction mechanisms of sodium with hydrogen fluoride and the adsorption of HF on the resultant NaF as well as the (NaF)
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tetramer. The results suggest that the reaction between Na and HF leads to the formation of sodium fluoride salt NaF and hydrogen gas. Na interacts with HF to form a complex HF···Na, and then the approaching of F atom of HF to Na results in a transition state H···F···Na. Accompanied by the broken of H-F bond, the bond forms between F and Na atoms as NaF, then the product NaF is yielded due to the removal of H atom. The resultant NaF can further form (NaF)
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tetramer. The interaction of NaF with HF leads to the complex NaF···HF; the form I as well as II of (NaF)
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can interact with HF to produce two complexes (i.e., (NaF)
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(I-1)···HF, (NaF)
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(I-2)···HF, (NaF)
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(II-1)···HF and (NaF)
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(II-2)···HF), but the form III of (NaF)
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can interact with HF to produce only one complex (NaF)
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(III)···HF. These complexes were explored in terms of noncovalent interaction (NCI) and quantum theory of atoms in molecules (QTAIM) analyses. NCI analyses confirm the existences of attractive interactions in the complexes HF···Na, NaF···HF, (NaF)
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(I-1)···HF, (NaF)
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(I-2)···HF, (NaF)
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(II-1)···HF and (NaF)
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(II-2)···HF, and (NaF)
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(III)···HF. QTAIM analyses suggest that the F···Na interaction forms in the HF···Na complex while the F···H hydrogen bonds form in NaF···HF, (NaF)
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(I-1)···HF, (NaF)
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(I-2)···HF, (NaF)
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(II-1)···HF and (NaF)
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(II-2)···HF, and (NaF)
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(III)···HF complexes. Natural bond orbital (NBO) analyses were also applied to analyze the intermolecular donor-acceptor orbital interactions in these complexes. These results would provide valuable insight into the chemical reaction of Na and HF and the adsorption interaction between sodium fluoride salt and HF.
Methods
The calculations were carried out at the M06-L/6-311++G(2d,2p) level of theory which were performed using the Gaussian16 program. Intrinsic reaction coordinate (IRC) calculations were carried out at the same level of theory to confirm that the obtained transition state was true. The molecular surface electrostatic potential (MSEP) was employed to understand how the complex forms. Quantum theory of atoms in molecules (QTAIM) and noncovalent interaction (NCI) analysis was used to know the topology parameters at bond critical points (BCPs) and intermolecular interactions in the complex and intermediate. The topology parameters and the BCP plots were obtained by the Multiwfn software.
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•ECG and flavonol di-glycosides accumulate in cultivars of assamica variety.•EGCG and flavonol tri-glycosides accumulate in cultivars of sinensis variety.•Flavonoids can be used as ...indicators for distinguishing various tea plant resources.•Accumulation pattern of flavonoids mainly depends on tea plant genetic background.
Flavonoids are important phenolic compounds in tea plant since they have a large number of physiological functions for plants themselves and human beings. Tea samples (n = 151) harvested from 3 varieties, 9 plantation areas and 107 cultivars were analyzed to describe the attributes of catechins and flavonol glycosides in China. A support vector machine (SVM) classifier was built to recognize the assamica variety with 94.2 % accuracy. Accumulation of (-)-epicatechin gallate (ECG) and flavonol di-glycosides was especially observed in assamica variety, while (-)-epigallocatechin gallate (EGCG) and flavonol tri-glycosides were obviously accumulated in sinensis variety. The ratios of ECG/EGCG and flavonol tri-glycosides/flavonol di-glycosides could be used as indicators for distinguishing the different varieties and cultivars. Accumulation pattern of catechins and flavonol glycosides were mainly dependent on the genetic background of the cultivars rather than plantation locations. The increased hydroxyl groups at the C-ring of catechins and the extended sugar chain at the B-ring of flavonol glycosides could be considered as important rules of metabolite change during tea plant evolution. The mechanism of accumulation of flavonoids in various varieties and cultivars was also discussed.
Some patients with diabetic foot ulcers (DFUs) may suffer from depression, but the latest information regarding the incidence of depression in patients with DFUs is limited. This review aimed to ...provide up-to-date information concerning the incidence of depression in patients with DFUs. We searched the literature in PubMed and Web of Science databases, limited to English publications. 11 eligible studies with a total of 2117 participants were included in this review. A random-effects model was applied due to high heterogeneity. The incidence of depression in patients with DFUs ranged from 26% (95% confidence interval CI = 19% to 33%) to 85% (95% CI = 78% to 92%), and was 47% (95% CI = 36% to 58%) after systematically summarizing. Subgroup analyses suggested that the incidence of depression were 49% (95%CI = 35% to 63%) in Europe, 37% (95% CI = 23% to 51%) in Asia, 62% (95% CI = 48% to 76%) in North America. Additionally, the incidence of depression were 40% (95% CI = 29% to 50%) in prospective studies, 55% (95% CI = 28% to 82%) in retrospective studies, 40% (95% CI = 29% to 50%) in cross-sectional studies. Furthermore, the incidence of depression were 43% (95% CI = 25% to 60%), 49% (95% CI = 35% to 63%), 68% (95% CI = 35% to 102%), 32% (95% CI = 26% to 38%), and 28% (95% CI = 18% to 38%) in patients with DFUs assessed by the Hospital Anxiety and Depression Scale, EuroQol 5-Dimension Questionnaire, Geriatric Depression Scale, Diagnostic and Statistical Manual of Mental Disorders, 4th edition, and the Center for Epidemiologic Studies Depression Scale, respectively. The estimates were robust in the sensitivity analysis. According to the meta-regression analyses, diabetes mellitus duration (t = 0.93, P = .422), publication years (t = −0.72, P = .488), and age of subjects (t = 0.01, P = .989) were not the sources of high heterogeneity. Our meta-analysis showed nearly half of patients with DFUs had depression problems.
Background
Calcium‐binding tyrosine phosphorylation‐regulated protein (CABYR) is a group of isoforms produced by alternative splicing and is overexpressed in human malignancies including ...hepatocellular carcinoma (HCC). However, the prognostic value and biological functions of its major protein isoforms, named CABYR‐a/b (combined CABYR‐a and CABYR‐b), in HCC remain to be established.
Methods
CABYR‐a/b expression was detected in HCC tissues and cell lines by quantitative real‐time polymerase chain reaction and Western blot analysis. The correlation of CABYR‐a/b expression with clinical characteristics and its prognosis impact were determined by statistical analysis. Finally, the biological functions and molecular mechanism of CABYR‐a/b were also investigated using molecular biology approaches.
Results
The present research found that CABYR‐a/b was markedly elevated in HCC specimens and cell lines. Upregulated CABYR‐a/b level had positive association with tumor size and differentiation in patients. Moreover, cases with elevated CABYR‐a/b level had poorer overall survival (OS) and disease‐free survival (DFS) than those with reduced CABYR‐a/b level. Multivariate analysis and prognostic nomograms demonstrated that CABYR‐a/b overexpression was an independent predictive indicator for OS and DFS. The calibration curve for the odds of OS and DFS demonstrated that the prediction by nomograms was in excellent accordance with actual situation. CABYR‐a/b downregulation suppressed cell proliferation and induced G1‐phase arrest via decreasing cyclin D1 and cyclin dependent kinase 4, while promoted apoptosis by reducing B‐cell lymphoma 2 (Bcl‐2) and increasing Bcl‐2‐associated death promoter.
Conclusion
Our research indicates that CABYR‐a/b exerts an oncogenic effect on HCC development and may become a new prognostic indicator for patients with HCC.
The present study has established that calcium‐binding tyrosine phosphorylation‐regulated protein (CABYR‐a/b) overexpression is an independent prognostic factor for overall survival and disease‐free survival in hepatocellular carcinoma (HCC). The calibration curve for probability of survival indicates excellent agreement between prediction by nomograms and actual observation. Mechanistically, CABYR‐a/b suppresses cell proliferation through regulating cyclin D1 and CDK4, and promotes cell apoptosis through modulating Bcl‐2 and BAD, thus functioning as an oncogene in HCC.
To evaluate the value of fasting plasma glucose (FPG) value in the first prenatal visit to diagnose gestational diabetes mellitus (GDM).
Medical records of 17,186 pregnant women attending prenatal ...clinics in 13 hospitals in China, including the Peking University First Hospital (PUFH), were examined. Patients with pre-GDM were excluded; data for FPG at the first prenatal visit and one-step GDM screening with 75-g oral glucose tolerance test (OGTT) performed between 24 and 28 weeks of gestation were collected and analyzed.
The median ± SD FPG value was 4.58 ± 0.437. FPG decreased with increasing gestational age. FPG level at the first prenatal visit was strongly correlated with GDM diagnosed at 24-28 gestational weeks (χ(2) = 959.3, P < 0.001). The incidences of GDM were 37.0, 52.7, and 66.2%, respectively, for women with FPG at the first prenatal visit between 5.10 and 5.59, 5.60 and 6.09, and 6.10-6.99 mmol/L. The data of PUFH were not statistically different from other hospitals.
Pregnant women (6.10 ≤ FPG < 7.00 mmol/L) should be considered and treated as GDM to improve outcomes; for women with FPG between 5.10 and 6.09 mmol/L, nutrition and exercise advice should be provided. An OGTT should be performed at 24-28 weeks to confirm or rule out GDM. Based on our data, we cannot support an FPG value ≥5.10 mmol/L at the first prenatal visit as the criterion for diagnosis of GDM.
Diffusive gradients in thin films technique (DGT) is recognized as a more reliable method for determining labile heavy metal (HM) concentration in soil than traditional destructive methods. However, ...the current DGT measurement index, CDGT, theoretically underestimates the true labile concentration (Clabile) of HMs in soil and lacks direct comparability with the conventional soil HM content indices due to unit differences. Here, we proposed CDGT-W, a new simple index which is defined as the HM accumulation in the binding layer, normalized to the weight of soil (optimized water content = 100% of the maximum water holding capacity) filled in the open cavity-type DGT device over a specified deployment time (optimized time = 24 h). The procedure for measuring CDGT-W is analogous to that of CDGT but includes precise determination of water content (water/dry soil) and the mass of soil filled in the cavity. We conducted measurements of Cu, Pb, Cr(Ⅵ) and As(V) as CDGT-W, CDGT, solution concentration (Csoln), and CaCl2 extractable concentration (CCaCl2) on three soils with a diverse range of HM concentrations. CDGT-W showed significant linear correlations with all other tested indexes. The ratios of CDGT-W to CCaCl2 varied between 0.30 and 0.98 for all HM–soil combinations with only one exception, a range much greater than CDGT/Csoln (typically <0.1) but lower than 1. This suggested that CDGT-W may more accurately reflect Clabile than CDGT (theoretically underestimates Cliable) and CCaCl2(likely overestimates Cliable). Additionally, CDGT-W measurements for these four HMs exhibited a broad measure concentration range and a low detection limit (mg/kg level). Consequently, CDGT-W may offer a more reliable alternative to CDGT for characterizing Clabile in unsaturated soils.
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•We proposed a new index CDGT-W to measure labile content of heavy metals in soil (Clabile).•CDGT-W linearly correlated to CaCl2 extractable content (CCaCl2) and CDGT.•CDGT-W may more accurately reflect Clabile than CDGT and CCaCl2.•CDGT-W is probably a better measure of Clabile than CDGT in unsaturated soil.
Pathophysiological micro-environments such as viscosity, polarity and hypoxia are tightly correlated with regulating diffusion, transportation, and intermolecular interactions in living cells. ...However, the interplay and crosstalk among these key factors have not been clearly explored yet due to the lack of practical tools. In this work, based on logic-gate, we developed a versatile fluorescent probe (VPHPP) for simultaneously detecting viscosity, polarity and Nitroreductases (NTRs) in living cells. This probe was able to distinguish cancer cells from normal cells with signals in blue channel (λem = 540 nm) for NTRs and red channel (λem > 747 nm) for viscosity/polarity, which seemed more accurate (or more information at least) to define the cell types than testing only one factor. Meanwhile, the dynamic changes of viscosity, polarity and NTRs were simultaneously observed under hypoxic conditions in living cells for the first time. Furthermore, the detection system could image the simultaneous down-regulation of NTRs and the elevation of viscosity level (decreasing polarity degree) induced by dicoumarin in living cells under a confocal microscopy. Last but not least, VPHPP could achieve the imaging in tumor-bearing mouse model. In brief, VPHPP could be used as a promising visualizing agent in image-guided surgery.
•A multifunctional fluorescent probe VPHPP was developed for simultaneously detecting viscosity, polarity and hypoxia.•Capable of distinguish cancer cells from normal cells through blue and far-red signals, respectively.•The cross-talk of viscosity, polarity and hypoxia under hypoxic conditions directly observed for the first time.•Revealing that dicoumarin could induce the upregulation of polarity (or decreased levels of viscosity) in living cells.•Achieve imaging tumors ex vivo and in vivo through two and signal channels separately.
With the rapid development of aerospace, the large complex curved workpiece is widely used. However, the lack of digital monitoring and detection in the current manufacturing process leads to the low ...efficiency of the parts produced and processed, and quality consistency cannot be guaranteed. Aiming at the problems of low degree of virtual visualization and insufficient monitoring ability of large complex surface machining, a framework of large complex surface machining monitoring system based on digital twin technology was proposed. The digital research of intelligent processing monitoring system is carried out from six dimensions. By studying the key technologies of virtual twin model construction, multi-source data acquisition and transmission, and virtual-real mapping relationship construction, a digital twin monitoring system for large complex surface machining is developed. Finally, the feasibility and effectiveness of the twin system are verified by a real scene, and it provides a reference for monitoring the machining process of large complex curved workpieces.
Cytochrome P450 3A4 (CYP3A4) is a key xenobiotic-metabolizing enzyme-mediated drug metabolism and drug-drug interaction (DDI). Herein, an effective strategy was used to rationally construct a ...practical two-photon fluorogenic substrate for hCYP3A4. Following two-round structure-based substrate discovery and optimization, we have successfully constructed a hCYP3A4 fluorogenic substrate (
) with desirable features, including high binding affinity, rapid response, excellent isoform specificity, and low cytotoxicity. Under physiological conditions,
is readily metabolized by hCYP3A4 to form a brightly fluorescent product (
) that can be easily detected by various fluorescence devices. The practicality of
for real-time sensing and functional imaging of hCYP3A4 has been examined in tissue preparations, living cells, and organ slices.
also demonstrates good performance for high-throughput screening of hCYP3A4 inhibitors and assessing DDI potentials
. Collectively, this study develops an advanced molecular tool for sensing CYP3A4 activities in biological systems, which strongly facilitates CYP3A4-associated fundamental and applied research studies.
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