Synthesis and Assembly of Photoresponsive Colloidal Tubes.

Inspired by the sophisticated multicomponent and multistage assembly of proteins and their mixtures in living cells, this study rationally designs and fabricates photoresponsive colloidal tubes that can self-assemble and hybrid-assemble when mixed with colloidal spheres and rods. Time-resolved observation and computer simulation reveal that the assembly is driven by phoretic attraction originating from osmotic pressures. These pressures are induced by the chemical concentration gradients generated by the photochemical reaction caused by colloidal tubes in a H2O2 solution under ultraviolet (UV) irradiation. The assembled structure is dictated by the size and shape of the constituent colloids as well as the intensity of the UV irradiation. Additionally, the resulting assembly can undergo self-propelled motion originating from the broken symmetry of the surrounding concentration gradients. This motion can be steered by a magnetic field and used for microscale cargo delivery. The study demonstrates a facile synthesis method for colloidal tubes and highlights their unique potential for controlled, hierarchical self-assembly and hybrid-assembly.

Development and validation of a nomogram predictive model for colorectal adenoma with low-grade intraepithelial neoplasia using routine laboratory tests: A single-center case-control study in China.

Background: Colorectal cancer (CRC) is the third most common cancer in the world and has a high mortality rate. Colorectal adenoma (CRA) is precancerous lesions of CRC. The purpose of the present study was to construct a nomogram predictive model for CRA with low-grade intraepithelial neoplasia (LGIN) in order to identify high-risk individuals, facilitating early diagnosis and treatment, and ultimately reducing the incidence of CRC. Methods: We conducted a single-center case-control study. Based on the results of colonoscopy and pathology, 320 participants were divided into the CRA group and the control group, the demographic and laboratory test data were collected. A development cohort (n = 223) was used for identifying the risk factors for CRA with LGIN and to develop a predictive model, followed by an internal validation. An independent validation cohort (n = 97) was used for external validation. Receiver operating characteristic curve, calibration plot and decision curve analysis were used to evaluate discrimination ability, accuracy and clinical practicability of the model. Results: Four predictors, namely sex, age, albumin and monocyte count, were included in the predictive model. In the development cohort, internal validation and external validation cohort, the area under the curve (AUC) of this risk predictive model were 0.946 (95%CI: 0.919-0.973), 0.909 (95 % CI: 0.869-0.940) and 0.928 (95%CI: 0.876-0.980), respectively, which demonstrated the model had a good discrimination ability. The calibration plots showed a good agreement and the decision curve analysis (DCA) suggested the predictive model had a high clinical net benefit. Conclusion: The nomogram model exhibited good performance in predicting CRA with LGIN, which can aid in the early detection of high-risk patients, improve early treatment, and ultimately reduce the incidence of CRC.

Colloidal antibiotic mimics: selective capture and killing of microorganisms by shape-anisotropic colloids.

The development of targeted and efficient antimicrobials for the selective killing of pathogenic bacteria is of great importance, yet remains challenging. Here, we propose a targeted approach to selectively capture and kill microorganisms with colloidal antibiotic mimics that are readily prepared by common chemical syntheses. The mimics are shape-anisotropic colloids, which can selectively capture shape-matching microorganisms due to lock-key depletion attractions. Furthermore, after being modified with gold nanoparticles (AuNPs) and irradiated with near-infrared light, the colloidal mimics can kill the selectively captured microorganisms due to the localized photothermal effect of the AuNPs. The work demonstrates the important ability of anisotropic colloids to selectively capture and precisely kill microorganisms, which holds considerable promise for safe and adaptive antibacterial therapies without the risk of antibiotic resistance.

Shape-Dictated Self-Assembly of Photoresponsive Hybrid Colloids.

The shape-dictated self-assembly of hybrid colloids induced by chemical concentration gradients generated by photocatalytic reactions of the colloids is studied. Different shapes enable the formation of assemblies with distinct lattice structures including hexagons, distorted hexagons, and squares, which are corroborated by computer simulations. Furthermore, assemblies change from lattices to chains when increasing the attraction between the colloids. The results show that photoresponsive hybrid colloids possess a unique capability for shape-dependent self-assembly, offering a practical and versatile approach to manipulate self-assembly at the microscale.

Comparative study of the dynamics of colloidal glass and gel.

We investigate and compare the difference in the dynamics of two arrested states: colloidal glass and colloidal gel. Real-space experiments reveal two distinct nonergodicity origins for their slow dynamics, namely, cage effects for the glass and attractive bondings for the gel. Such distinct origins lead to a faster decay of the correlation function and a smaller nonergodicity parameter of the glass than those of the gel. We also find that the gel exhibits stronger dynamical heterogeneity compared with the glass due to the greater correlated motions in the gel. Moreover, a logarithmic decay in the correlation function is observed as the two nonergodicity origins merge, consistent with the mode coupling theory.

A Versatile Method for Synthesis of Light-Activated, Magnet-Steerable Organic-Inorganic Hybrid Active Colloids.

The immense potential of active colloids in practical applications and fundamental research calls for an efficient method to synthesize active colloids of high uniformity. Herein, a facile method is reported to synthesize uniform organic-inorganic hybrid active colloids based on the wetting effect of polystyrene (PS) with photoresponsive inorganic nanoparticles in a tetrahydrofuran/water mixture. The results show that a range of dimer active colloids can be produced by using different inorganic components, such as AgCl, ZnO, TiO2, and Fe2O3 nanoparticles. Moreover, the strategy provides a simple way to prepare dual-drive active colloids by a rational selection of the starting organic materials, such as magnetic PS particles that result in light and magnet dual-drive active colloids. The motions of these active colloids are quantified, and well-controlled movements are demonstrated.

Evaluation of Tigecycline Utilization and Trends in Antibacterial Resistance from 2018 to 2021 in a Comprehensive Teaching Hospital in China.

Purpose: Tigecycline, the first glycylcycline antibiotic, which was widely used for off-label indications because of its broad-spectrum antibacterial activity. This study evaluated the indications for clinical use of tigecycline, clinical and microbiological effectiveness, factors associated with in hospital mortality, and bacterial resistance. Methods: This retrospective study evaluated all inpatients who received tigecycline treatment for >72 hours between January 2018 and December 2021 in a comprehensive teaching hospital in China. The evaluation included indications, administration regimen, etiology, efficacy and so on. Univariate and multivariate analyses were used to evaluate the risk factors for all-cause mortality. Results: There were 203 patients treated with tigecycline. Tigecycline was commonly prescribed for off-label indications (83.25%, 169/203), and hospital-acquired pneumonia ranked first (79.29%, 134/169). The most common pathogen was Acinetobacter baumannii. Clinical and microbiological success was 57.14% (116/203) and 32.28% (41/127), respectively. Fifty-four patients died and all-cause mortality was 26.60%. Univariate and multivariate analyses showed no significant difference in age, gender, off-label indication, duration of treatment, combination with other drugs, multidrug-resistant or extensively drug-resistant infections and tigecycline application scoring with respect to mortality. Conclusion: Although detection of A. baumannii has decreased in the past 4 years in our hospital, resistance to tigecycline has increased. For clinical application, physicians attach importance to detection of pathogenic microorganisms, but there is still empirical medication without bacterial culture reports. Therefore, an antibiotic stewardship program oriented toward tigecycline should be strengthened to curb bacterial resistance.

Artificial Extracellular Matrix Composed of Heparin-Mimicking Polymers for Efficient Anticoagulation and Promotion of Endothelial Cell Proliferation.

Heparin-mimicking polymers have emerged as an alternative to heparin to construct effective and safe anticoagulant surfaces. However, the present heparin-mimicking polymers are usually limited to the combinations of glucose and sulfonic acid units, and the structure origin of their anticoagulant properties remains vague. Inspired by the structure of natural heparin, we synthesized a series of novel heparin-mimicking polymers (named GSAs) composed of three units, glucose, sulfonic acid, and carboxylic acid. Then, we constructed artificial extracellular matrices composed of GSAs and two typical cationic polymers, polyethyleneimine and chitosan, to investigate the anticoagulation and endothelialization of GSAs. By changing the ratio of the three units, their functions in the matrices were studied systematically. We found that an increase in the sulfonic acid content enhanced surface anticoagulant activity, an increase in glucose and sulfonic acid content promoted the proliferation of human umbilical vein vascular endothelial cells, and an increase in the carboxylic acid content inhibited the adherence of human umbilical vein vascular smooth muscle cells. This work uncovers the important role of the GSAs structure to the anticoagulation properties, which sheds new light on the design and preparation of heparin-mimicking polymers for practical engineering applications.

A self-cleaning surface based on UV-activatable, AgCl micropumps for bacterial killing and removal.

We report a self-cleaning, bacterial killing surface by immobilization of AgCl microparticles on a surface, acting as chemical micropumps. The surface shows a high bacterial killing efficacy of attached bacteria and exhibits sustainable removal of bacteria as a result of UV-activatable micropumping originating from the photocatalytic reaction of AgCl microparticles. Our work provides an advance in the sustainable use of bacterial contact-killing surfaces stricto sensu through removal of dead bacteria and debris that may shield contact-killing sites.

Synthesis of Rod-Shaped ZnO/Polysiloxane Micromotors with Patch-Dependent Motion Modes.

Inorganic particles with photocatalytic properties are excellent candidates for the fabrication of micromotors. To achieve self-propulsion, the geometric and chemical symmetries of inorganic particles should be broken. However, the synthesis of micromotors with different geometric and chemical symmetries remains challenging. In this paper, a simple synthesis method is proposed to prepare rod-shaped micromotors with different patches, leading to distinct geometric and chemical symmetries. The micromotors are composed of zinc oxide (ZnO) microrods partially patched with polysiloxanes at different positions. The patches of the micromotors can be roughly regulated by varying the amount of siloxanes used in the synthesis. These micromotors are propelled in H2O2 solution by an ionic self-diffusiophoresis mechanism, which exhibits two motion modes, including linear motion and circular motion, due to different patch positions. Moreover, the degradation of organic dyes by the micromotors depending on the patches is demonstrated.

Reconfiguring Self-Assembly of Photoresponsive Hybrid Colloids.

The reconfigurable self-assembly of colloidal particles allows the bottom-up creation of adaptive materials, yet significant challenges remain. Here, we demonstrate a synthesis of photoresponsive Fe2O3/polysiloxane hybrid colloids that perform a dynamically reconfigurable self-assembly. Such self-assembly is due to chemical gradients originating from the decomposition of H2O2 by the Fe2O3 component under UV irradiation. The morphology of the self-assembly includes chains and flower-structures, where the chains can be transformed in situ into flower-like structures with decreasing UV intensity. The flower-structures can be further switched by applying an external magnetic field, leading to orientationally ordered clusters. This, interestingly, leads to an asymmetrical chemical gradient surrounding the assemblies, and transforms the cluster into a micromotor exhibiting a self-propulsion steerable by the magnetic field. Our findings demonstrate a new possibility to control and reconfigure the self-assembly of colloids, which offers an important pathway for fabrications of adaptive and smart materials at the microscale.

Clinical practice guidelines for management of dual antiplatelet therapy in patients with noncardiac surgery: A critical appraisal using the AGREE II instrument.

WHAT IS KNOWN AND OBJECTIVE: Despite the availability of clinical practice guidelines (CPGs), there are considerable differences in their recommendations in the perioperative management of stented patients who need elective noncardiac surgery. Our aim was to systematically review the quality of CPGs for perioperative management of dual antiplatelet therapy (DAPT) and summarize the recommendations. METHODS: A systematic search for perioperative DAPT guidelines was conducted on PubMed, Embase and websites of guideline organizations and professional societies until 4 February 2021. Independently, two assessors appraised the quality of CPGs using the Appraisal of Guidelines for Research & Evaluation II (AGREE II) instrument and extracted the data. Recommendations were summarized, and a comparative study was conducted to analyse the consistency among guidelines. RESULTS AND DISCUSSION: A total of 10 guidelines fulfilled our inclusion criteria. The domain of scope and purpose and clarity of presentation obtained the highest median scores, while the domain of stakeholder involvement and rigour of development obtained the lowest median scores. Three guidelines (ACCP, ESC/ESA and ACC/AHA) with a score of at least 60% in most AGREE II domains were recommended. Recommendations across perioperative management of DAPT guidelines were inconsistent. WHAT IS NEW AND CONCLUSION: The ACCP, ESC/ESA and ACC/AHA CPGs were recommended. There is a need for high-quality prospective studies assessing different management strategies on this issue. Given the lack of consensus, the results of this study will help to guide perioperative dual antiplatelet management strategies for patients with coronary stents who are undergoing noncardiac surgery.

The impact of pharmacist intervention on prophylactic antibiotics use in orthopedic surgery at a hospital in China.

ABSTRACT: This study aimed to assess the impact of the pharmacist-led intervention on perioperative antibiotic prophylaxis by standardizing the cephalosporin intradermal skin test in the orthopedic department.A pre-and postintervention study was conducted among patients in the Orthopedics Department at the Beijing Chao-Yang Hospital in China. Use of intradermal skin test, perioperative antibacterial prophylaxis, and cost of care were compared between the preintervention population (admitted from 6/1/2018 to 8/31/2018) and postintervention population (admitted from 1/1/2019 to 3/31/2019). Logistic regression and generalized linear regression were used to assess the intervention impact.425 patients from the preintervention period and 448 patients from the postintervention period were included in the study. After the implementation of the pharmacist intervention program, there was a decrease in the utilization of intradermal skin tests, from 95.8% to 16.5% (P < .001). Patients were more likely to have cephalosporin as prophylactic antimicrobials (OR = 5.28, P < .001) after the implementation. The cost of antimicrobials was significantly reduced by $150.21 (P < .001) for each patient.Pharmacist-involved intervention can reduce the utilization of cephalosporins skin tests and decrease the prescription of unnecessary high-cost antimicrobials.

Colloidal assembly manipulated by light-responsive Ag3PO4 nanoparticles.

We report controllable assembly of polystyrene (PS) microspheres via a photocatalytically driven electroosmotic flow deriving from UV irradiation of Ag3PO4 nanoparticles in water. A series of assembly phases, including crystallites, chains and gels, are programmed by systematically modulating the UV intensity, the packing density of the PS microspheres and the concentration of the Ag3PO4 nanoparticles. Our findings demonstrate an important ability of light-responsive nanoparticles for colloidal assembly, which offers a new pathway toward effective manipulation of assembly at the microscale.

MiR-374b-5p inhibits KDM5B-induced epithelial-mesenchymal transition in pancreatic cancer.

Micro(mi)RNAs play a critical regulatory role in the progression and metastasis of pancreatic cancer (PC). In this study, we aimed to reveal the mechanisms of miR-374b-5p in regulating epithelial-mesenchymal transition (EMT) in PC. Gene Expression Omnibus datasets (GSE24279 and GSE71533) and the pancreatic ductal adenocarcinoma (PDAC) cohort of The Cancer Genome Atlas were employed to screen for potential prognostic miRNAs. The expression of miR-374b-5p was measured by quantitative real-time polymerase chain reaction (qRT-PCR) in 78 paired PDAC tissue samples. The biological effects of miR-374b-5p were investigated using in vitro and in vivo assays. Luciferase reporter assays and immunohistochemical tests were conducted to verify the interaction between miR-374b-5p and its predicted direct target, KDM5B. MiR-374b-5p was downregulated in PC tissues, and a low level of miR-374b-5p was associated with poor overall survival, greater tumor size, and more lymph node metastasis in PC. In vitro assays indicated that overexpression of miR-374b-5p suppressed the proliferation, migration, and invasion of PC cells. Mechanistically, miR-374b-5p suppressed the expression of KDM5B, which inhibited E-cadherin expression but promoted N-cadherin and vimentin expression. Finally, in vivo assays demonstrated that miR-374b-5p overexpression suppressed tumor growth and lung metastasis in PANC-1 cells. Thus, our findings indicate that miR-374b-5p could be a potential prognostic biomarker and therapeutic target for KDM5B-induced EMT in PC.

Single-cell transcriptomics reveals heterogeneous progression and EGFR activation in pancreatic adenosquamous carcinoma.

Pancreatic adenosquamous carcinoma (PASC) - a rare pathological pancreatic cancer (PC) type - has a poor prognosis due to high malignancy. To examine the heterogeneity of PASC, we performed single-cell RNA sequencing (scRNA-seq) profiling with sample tissues from a healthy donor pancreas, an intraductal papillary mucinous neoplasm, and a patient with PASC. Of 9,887 individual cells, ten cell subpopulations were identified, including myeloid, immune, ductal, fibroblast, acinar, stellate, endothelial, and cancer cells. Cancer cells were divided into five clusters. Notably, cluster 1 exhibited stem-like phenotypes expressing UBE2C, ASPM, and TOP2A. We found that S100A2 is a potential biomarker for cancer cells. LGALS1, NPM1, RACK1, and PERP were upregulated from ductal to cancer cells. Furthermore, the copy number variations in ductal and cancer cells were greater than in the reference cells. The expression of EREG, FCGR2A, CCL4L2, and CTSC increased in myeloid cells from the normal pancreas to PASC. The gene sets expressed by cancer-associated fibroblasts were enriched in the immunosuppressive pathways. We demonstrate that EGFR-associated ligand-receptor pairs are activated in ductal-stromal cell communications. Hence, this study revealed the heterogeneous variations of ductal and stromal cells, defined cancer-associated signaling pathways, and deciphered intercellular interactions following PASC progression.

2D Colloidal Crystals with Anisotropic Impurities.

We report a study of 2D colloidal crystals with anisotropic ellipsoid impurities using video microscopy. It is found that at low impurity densities, the impurity particles behave like floating disorder with which the quasi-long-range orientational order survives and the elasticity of the system is actually enhanced. There is a critical impurity density above which the 2D crystal loses the quasi-long-range orientational order. At high impurity densities, the 2D crystal breaks into polycrystalline domains separated by grain boundaries where the impurity particles aggregate. This transition is accompanied by a decrease in the elastic moduli, and it is associated with strong heterogeneous dynamics in the system. The correlation length vs impurity density in the disordered phase exhibits an essential singularity at the critical impurity density.

2D isotropic-nematic transition in colloidal suspensions of ellipsoids.

Liquid crystals are important condensed matter systems for technological applications, as well as for fundamental studies. An important unresolved issue is the nature of the phase transition in a two-dimensional (2D) liquid crystal system. In contrast to numerous computational studies reported in the last few decades, there have been no convincing experiments to verify these numerical results. Anisotropic colloids provide an excellent experimental model system to study phase transitions, such as crystallization and glass transition in condensed matter physics with single particle resolution. However, using colloids to probe the two-dimensional liquid crystal transition remains a challenge, since the condensed anisotropic colloids usually become stuck in the metastable glassy state rather than approaching their equilibrium liquid crystal phase. Here we report a method of using an external magnetic field to assist a colloidal system of super-paramagnetic anisotropic particles to overcome the local free energy barriers in the metastable states and approach the equilibrium phase. The experiments demonstrate a 2D isotropic-nematic phase transition with increasing packing density. The effects of the anisotropy of the colloidal particles on the 2D isotropic-nematic transition are explored. Our experimental results are compared with those from previous computational work, and quantitative agreements are reached.

Magnetic matchstick micromotors with switchable motion modes.

The ability to in situ tune various motion modes of micromotors is challenging, yet critical for any practical applications of micromotors in complex microenvironments. Here, we designed and synthesized magnetic matchstick micromotors with two motion modes, a persistent rotational motion and a straight-line motion, that can be readily and reversibly switched in situ by an external magnetic field. Such micromotors with switchable motion modes hold considerable promise for local environment sensing and probing at the microscale.

Shape-Tunable Janus Micromotors via Surfactant-Induced Dewetting.

The ability to tune shapes of micromotors is challenging yet crucial for creating intelligent and functional micromachines with shape-dependent dynamics. Here, we demonstrate a facile strategy to synthesize Janus micromotors in large quantity whose shapes can be precisely tuned by a surfactant-induced dewetting strategy. The Janus micromotor is composed of a TiO2 microparticle partially encapsulated within a polysiloxane microsphere. A range of particle shapes, from approximately spherical to snowman, is achieved, and the shape-tunable dynamics of the micromotors are quantified. Our strategy is versatile and can be applicable to other photoactive materials, such as ZnO and Fe2O3 nanoparticles, demonstrating a general approach to synthesize Janus micromotors with controllable shapes. Such shape-tunable micromotors provide colloidal model systems for fundamental research on active matter, as well as building blocks for the fabrication of micromachines.