Search

Objectives: Our previous studies showed that strontium (Sr)‐modified sand‐blasted, large grit, acid etched titanium surface (Sr‐SLA) is beneficial for osseointegration; however, the supporting mechanisms have not been explored in detail. Materials and Methods: Whole‐transcriptome RNA sequencing of peri‐implant bone tissue was performed, and CDH2 was selected as a key mediator of Sr‐SLA‐mediated osseointegration. To test this hypothesis, a lentivirus‐mediated vector targeting the silencing of the CDH2 gene was used in mesenchymal stem cells (MSCs) prior to seeding on Ti substrates. The effects of CDH2 interference on MSCs vitality, differentiation, and β‐catenin signaling activity were evaluated. In vivo, a recombinant adeno‐associated virus 9 vector carrying an artificial siRNA that target CDH2 (AAV9‐CDH2i) was intravenously injected in mice, followed by tibial surgery with implant placement. Osseointegration were monitored using micro‐CT analysis. Results: CDH2 expression in MSCs on Sr‐SLA was higher than the control group, which was in parallel with the enhanced cell migration, adhesion, and upregulation of early osteogenic markers. Knocking down CDH2 in MSCs resulted in decreased cell viability and osteogenic differentiation, and the elevated biocompatibility and osteoinductive effect of Sr‐SLA were greatly diminished. Surprisingly, Sr‐SLA‐induced upregulation of CDH2 was not followed by restriction of β‐catenin signaling because Sr‐SLA also promoted the expression and nuclear translocation of β‐catenin. Systemic administration of AAV9‐CDH2i effectively knocked down CDH2 expression in bone marrow cells, and in turn, inhibited bone formation induced by Sr‐SLA. Conclusions: The results indicated that CDH2 is required for Sr‐SLA‐mediated bone regeneration, which reveals a new mechanism to explain the osteoinductive effect of Sr‐SLA. Thus, biomaterial modifications targeting CDH2 may help improve early osseointegration and bone healing. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of fruit and vegetable intake on gut microbiota using a mouse model of metabolic syndrome (MS) induced by a high‐fat diet. Forty‐eight male mice were randomly divided into four groups, control group (C), high‐fat diet‐fed model group (H), high fat plus low intake of fruits and vegetables diet‐fed group (H.LFV), high fat plus high intake of fruits and vegetables diet‐fed group (H.HFV), and each group were fed for 60 days. During the experiment, mouse body weights were recorded and fecal samples were collected. Cetyltrimethyl ammonium bromide (CTAB) method was used to extract fecal bacterial DNA, and the purity and concentration of the DNA were detected by electrophoresis. DNA samples underwent PCR amplification (primers in 16 S V4 (515F and 806R)). Raw sequencing data were processed, and sample complexity and multiple‐sample comparisons were investigated. Mouse organ coefficient, serum lipid levels, fecal TC (total cholesterol) and TBA (total bile acid) levels, and hepatic glutathione and malondialdehyde levels were determined. Compared to the H group, the fecal TC and TBA levels decreased significantly in the H.HFV group (p <.05), and hepatic glutathione and malondialdehyde levels decreased significantly in both H.LFV and H.HFV groups (p <.05). Decreased abundance of Firmicutes, Burkholderiales, Syntrophomonas, and Pseudomonadales in gut microbiota was observed in H.LFV and H.HFV groups compared to the H group. The Anosim results showed significant differences in pairwise comparison between groups. The linear discriminant analysis effect size (LEfSe) results showed that k_bacteria not only exhibited statistically differences between H and C groups but also among H.LFV, H.LFV, and H groups, and hence, could be used as a biomarker between groups. To sum up, fruit and vegetable powder could increase the fecal excretion of TC and TBA, and the antioxidant capacity in C57BL/6N mice. Meanwhile, the mechanism that fruit and vegetable powder could prevent MS in C57BL/6N mice was related to the decreased abundance of gut microbiota, including Firmicutes, Syntrophomonadales, and Pseudomonadales. Hence, fruit and vegetable powder could be used as a recommended food to regulate gut microbiota and prevent the occurrence of MS‐related diseases. [ABSTRACT FROM AUTHOR]

A strategy is proposed to generate single microdrops with femtoliter to microliter volumes as a liquid reactor and to guide them towards a reactive surface within a viscous carrier liquid. Reactions of the drop content with the surface are exemplified by exhaustive electrolysis of the reactor content, making use of an ion‐conducting pathway through the carrier liquid. The mechanisms by which the redox‐active species from the aqueous drop reach the electrode surface were established by a combination of time‐lapse microscopy of the drop shape, chronoamperometric recording of the single drop electrolysis, and modelling of the reaction‐transport problem, showing that partitioning over the liquid‐liquid interface must be a key step in this mechanism. The possibilities of reagent delivery and external triggering of a reaction are expanded by the possibility for controlled addition of further dissolved reactants to the liquid microreactor. [ABSTRACT FROM AUTHOR]

BACKGROUND: 10‐Hydroxy‐cis‐12‐octadecenoic acid (10‐HOE, 10‐OH C18:1), an emerging functional fatty acid, has anti‐fungal and anti‐inflammatory effects. 10‐HOE is synthesized by bacterial 10‐linoleic acid hydratase (10‐LHT) with linoleic acid as the substate. However, the characterization of 10‐LHT and its targeted synthesis of 10‐HOE have been rarely reported. In this study, the recombinant 10‐LHT from Lactiplantibacillus plantarum ZS2058 was characterized, and the biocatalysis of 10‐HOE using crude enzyme was optimized. RESULTS: The recombinant 10‐LHT catalyzed the conversion of linoleic acid (C18:2) to 10‐HOE as identified using gas chromatography‐mass spectrometry (GC–MS). It showed a molecular weight of about 70 kDa on sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS‐PAGE), and was a flavin adenine dinucleotide (FAD)‐dependent enzyme. The activity of 10‐LHT was optimal at pH 6.5 and 25 °C, and it was pH‐stable but thermo‐sensitive. The optimal condition for the 10‐HOE biosynthesis using crude enzyme was 5 g L−1 linoleic acid (C18:2), 148.0 U mL−1 10‐LHT, 0.05 mmol L−1 FAD, 2% methanol and 100 mmol L−1 sodium chloride at 25 °C and pH 6.5. A conversion yield of 47.8 ± 1.5% and the corresponding 10‐HOE concentration of 2.4 ± 0.1 g L−1 were achieved at 48 h under the optimal reaction conditions. CONCLUSION: This work achieved the highest conversion yield of 10‐HOE with the highest substrate concentration, and provides some useful information for the industrial production of 10‐HOE. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The precise and effective generation and manipulation of micron‐sized droplets is crucial for chemical and biological research and applications. Normally, droplets generation and manipulation are achieved by two separate devices/systems with their respective operation strategies. Pipette, inkjet nozzle, and microfluidic channels equipped with programed syringes are commonly used for droplets generation whereas the subsequent manipulation is normally achieved by leveraging of forces originating either from optical, electric, magnetic or acoustic field and the corresponding complicated devices. Here we report a new paradigm that can realize simultaneous droplets generation and manipulation in an immiscible liquid environment using only the confined interface vibration generated by the ordinary inkjet nozzle. Droplets, ranging from femtoliter to picoliter, can be generated and manipulated without interruption since they are actuated by the same nozzle. Our strategy provides a platform for precise generation and manipulating the micro‐sized droplets that may be valuable for applications requiring simple setups and seamless connection between droplets generation and droplets manipulation. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the retinal vessel oxygen saturation in patients with internal carotid artery stenosis (ICAS). Methods: This is a cross‐sectional study. Sixteen patients with unilateral moderate or worse ICAS (≥50%) and no fundus diseases were included in the study. Sixteen gender‐ and age‐matched healthy subjects were selected as controls. The mean oxygen saturation and vessel diameters of the retinal arterioles and venules were obtained using a dual‐wavelength spectrophotometric retinal oximeter. Results: In the eye of the stenotic side, the retinal vessel oxygen saturation was 100.14 ± 10.27% in the arterioles and 56.50 ± 10.79% in the venules, and the arteriovenous (A‐V) difference was 43.63 ± 7.71%. In the eye of the contralateral side, the oxygen saturation was 96.55 ± 7.50% in the arterioles and 57.42 ± 9.84% in the venules, and the A‐V difference was 39.39 ± 6.33%. In healthy subjects, the oxygen saturation was 93.22 ± 5.98% in the arterioles and 56.57 ± 7.05% in the venules, and the A‐V difference was 36.65 ± 7.33%. The arteriolar oxygen saturation in the stenotic side was higher than that in the contralateral side (p = 0.025) and that in the healthy subjects (p = 0.027), and the A‐V difference in the stenotic side was significantly higher than that in the contralateral side (p = 0.009) and that in the healthy subjects (p = 0.013). The diameters of the arterioles in the stenotic side were smaller than those in the healthy subjects (p = 0.030). Conclusions: Patients with ICAS had decreased retinal arteriole diameters and increased retinal vessel oxygen saturation in the arterioles and A‐V differences, suggesting the presence of microcirculation disorder and hyperoxia in the retina. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is a fatal disease ranking the third among the commonplace cancer types around the world. It is extremely significant to exploit effective treatments against CRC. FAM225A was proved to influence cell progression and forecast unfavorable prognosis in nasopharyngeal carcinoma. The role and function mechanism of FAM225A are still unclear in CRC. In this research, FAM225A was discovered presenting much higher expression in CRC tissues and cell lines. In addition, depleting FAM225A was capable of inhibiting cell proliferation, migration, and epithelial‐to‐mesenchymal transition (EMT) progress, and enhancing cell apoptosis ability. Furthermore, miR‐613 exerted important effects as a mediator between FAM225A and NOTCH3. NOTCH3 was negatively correlated with miR‐613, whereas was positively associated with FAM225A. Via competitively binding with miR‐613, FAM225A positively regulated NOTCH3 expression. FAM225A facilitated CRC occurrence and development through positively regulating NOTCH3 expression by binding with miR‐613. In a word, FAM225A/miR‐613/NOTCH3 axis may play a tumor‐facilitator in CRC cell progression. These data manifested the pivotal effect of FAM225A/miR‐613/NOTCH3 pathway in CRC cell proliferation, apoptosis, and migration process. The findings may provide some theoretical basis and different perspective for CRC treatment. [ABSTRACT FROM AUTHOR]

Quaternion equality constrained least squares problem is an extremely effective tool in studying quantum mechanics and quantum field theory. However, the computation of the quaternion equality constrained least squares problem is extremely complex. In this paper, we first prove that quaternion equality constrained least squares problem is equivalent to weighted quaternion least squares problem when the parameter τ→+∞. Then, for weighted quaternion least squares problem, applying the special structure of real representation of quaternion, we propose real structure–preserving algorithm to obtain the solution of quaternion equality contained least squares problem. At last, we give numerical examples to illustrate the effectiveness of our method. [ABSTRACT FROM AUTHOR]

In today's era, the inkjet printing (IJP) technique plays important roles in the fabrication of mechanical, electronical, and even biological devices. However, the current IJP techniques are incapable of handling viscous inks, which greatly hinder the extensive industrial application. Here, it is found that utilizing the superhydrophobic materials on the end surface of a nozzle combined with the dragging and shearing effects of an airflow, micrometer‐sized droplets can be generated under a quite low ejection/extrusion pressure. This variation of the traditional IJP technique is called pneumatic conveying printing (PCP) and is capable of handling viscous inks. Two PCP prototypes using micropump and micropiezo as the ink extruder, respectively, are homemade to demonstrate the printing performance. For the PCP using micropump inks with viscosities as high as several thousand mPa s can be printed. For the PCP using a micropiezo, the maximum allowed viscosity is about 700 mPa s. Furthermore, the pressure within the pipeline or ink chamber and the shear rate at the orifice during PCP are much smaller than those of the traditional IJP due to the slower ink extrusion rate. Both experiment and simulation are carried out to reveal the mechanisms of the proposed PCP technique. [ABSTRACT FROM AUTHOR]

Electron transfer, ionic liquids, femtoliter reactor, bulk electrolysis Keywords: electron transfer; ionic liquids; femtoliter reactor; bulk electrolysis EN electron transfer ionic liquids femtoliter reactor bulk electrolysis 1 1 1 04/28/22 20220426 NES 220426 B The Front Cover b illustrates a single microscopic drop which is generated and directed to a reactive surface, where the liquid content is detected. [Extracted from the article]

This article proposes a methodology for the application of Bayesian networks in conducting quantitative risk assessment of operations in offshore oil and gas industry. The method involves translating a flow chart of operations into the Bayesian network directly. The proposed methodology consists of five steps. First, the flow chart is translated into a Bayesian network. Second, the influencing factors of the network nodes are classified. Third, the Bayesian network for each factor is established. Fourth, the entire Bayesian network model is established. Lastly, the Bayesian network model is analyzed. Subsequently, five categories of influencing factors, namely, human, hardware, software, mechanical, and hydraulic, are modeled and then added to the main Bayesian network. The methodology is demonstrated through the evaluation of a case study that shows the probability of failure on demand in closing subsea ram blowout preventer operations. The results show that mechanical and hydraulic factors have the most important effects on operation safety. Software and hardware factors have almost no influence, whereas human factors are in between. The results of the sensitivity analysis agree with the findings of the quantitative analysis. The three-axiom-based analysis partially validates the correctness and rationality of the proposed Bayesian network model. [ABSTRACT FROM AUTHOR]