Thermal-Responsive Gel-Based Overheat Limiter Enabled Intelligent Photothermal Therapy.

Uncontrolled and excessive photothermal heating in photothermal therapy (PTT) inevitably causes thermal damage to surrounding normal tissues, severely limiting the universality and safety of PTT. To address this issue, an intelligent cooling thermal-responsive (ICTR) gel containing poly(N-isopropylacrylamide-co-acrylamide) (P(NIPAM-AM))microgel is applied onto the skin to realize intelligent PTT, which can avoid excessive heating and accidental injury. The high near-infrared (NIR) light transmittance (> 95%) of the ICTR gel ensures effective light delivery at low temperatures, while the refractive index of the P(NIPAM-AM) microgel increases remarkably when the temperature exceeds a predetermined threshold, resulting in progressively enhanced light scattering and weakened photothermal conversion. In animal studies, the negative feedback regulation of ICTR gel on light transmittance and photothermal heating allows the photothermal temperature in the lesion site to be stabilized within the effective therapeutic range (45 °C) while ensuring that the skin surface temperature does not exceed 35 °C. Compared with the severe skin thermal damage found in the histological staining of mice skin receiving conventional PTT, the mice skin receiving the ICTR gel-enabled intelligent PTT remains in good condition. This study establishes an intelligent and universal paradigm for PTT thermal regulation, which is of great significance for achieving safe and effective PTT.

Stretchable, Programmable and Magnet-Insensitive Protonic Display Based on Integrated Ionic Circuit.

As a new approach to "More than Moore", integrated ionic circuits serve as a possible alternative to traditional electronic circuits, yet the integrated ionic circuit composed of functional ionic elements and ionic connections is still challenging. Herein, a stretchable and transparent ionic display module of the integrated ionic circuit has been successfully prepared and demonstrated by pixelating a proton-responsive hydrogel. It is programmed to excite the hydrogel color change by a Faraday process occurring at the electrode at the specific pixel points, which enables the display of digital information and even color information. Importantly, the display module exhibits stable performance under strong magnetic field conditions (1.7 T). The transparent and stretchable nature of such ionic modules also allows them to be utilized in a broad range of scenarios, which paves the way for integrated ionic circuits.

Deepened Photodynamic Therapy through Skin Optical Clearing Technology in the Visible Light Window.

The trade-off that shorter wavelength light facilitates the efficient generation of reactive oxygen species (ROS) from photosensitizer (PS) while facing the drawback of limited penetration depth through skin tissue restricts the further development of photodynamic therapy (PDT). Here, we address this contradiction and achieve visible-light-tailored deep PDT combined with the skin optical clearing technology. With the help of the prepared skin optical clearing gel, the refractive index inhomogeneity between skin tissue components is greatly attenuated, and the light scattering effect within the skin tissue is remarkably reduced. As a consequence, the transmittance of visible light at 600 nm through in vitro porcine skin and in vivo mouse skin after treatment increases from approximately 10 and 40 to 70 and 70%, respectively. Furthermore, in the tumor cell eradication experiment, the local ROS generation efficiency in the experimental group is several times higher than that in the control group owing to improved visible transmittance, which is thus responsible for the complete eradication of tumor cells, even when shaded by skin tissue. The results suggest that this strategy may serve as a valuable supplement to the current deep PDT strategies.

Revealing the Mechanism of Ink Flaking from Surfaces of Palm Leaves (Corypha umbraculifera).

Palm leaves are the primary literary support in South and Southeast Asia before the widespread use of paper. However, palm leaf manuscripts face the threat of information loss due to the persistent issue of ink flaking during long-term preservation. Herein, we focus on studying the botanical structure, surface properties, and surface composition of palm leaves to gain an insightful understanding of the mechanism of ink flaking. According to the surface energy analysis, the surface of palm leaves is dominated by the dispersive component due to the presence of hydrophobic substances, resulting in the weak interaction between the handwriting and palm leaves. Moreover, the accumulation of silicon on palm leaves creates a "cuticle-silicon double layer", leading to a dense structure that hinders deep ink absorption. These two main reasons are considered to cause the ink flaking easily, which is further proven by the ink flaking test with the simulated palm leaf manuscripts. To the best of our knowledge, this is the first in-depth technical study on the adhesion performance of handwriting on plant leaves. This work also provides a theoretical basis for the study of the deterioration, adhesive repair, enhancement of flexibility, handwriting reinforcement, and beyond, which contributes to the conservation of precious palm leaf manuscripts.

Stabilizing Liquid in Precise Nonequilibrium Shapes via Fast Interfacial Polymerization.

Due to the minimization of interface area caused by surface tension, the stabilization of liquid in complex and precise nonequilibrium shapes is challenging. In this work, a simple, surfactant-free, and covalent strategy to stabilize liquid in precise nonequilibrium shapes via fast interfacial polymerization (FIP) of highly reactive n-butyl cyanoacrylate (BCA) monomer triggered by water-soluble nucleophiles is described. Full interfacial coverage can be achieved instantly, and the resultant polyBCA film anchored at the interface can support the unequal interface stress, which allows the production of non-spherical droplets with complex shapes. Notably, the formulation of internal aqueous phase is nearly unaffected since no specific additive is required. Moreover, considering the excellent biocompatibility of BCA and polyBCA, the produced droplets can be used as micro-bioreactor for enzyme catalysis and even bacterial culture, which well mimic the morphology of cells and bacteria to achieve the biochemical reaction in non-spherical droplets. The present work not only opens a new sight for the stabilization of liquid in nonequilibrium shapes, but may also promote the development of synthetic biology based on non-spherical droplets, and tremendous potential applications are anticipated.

Fast Interfacial Polymerization for Stabilizing Emulsion Droplets with Polymer Films beyond Emulsifiers.

Stabilizing emulsion droplets with amphiphilic emulsifiers are the current prevailing method, but the extensive use of such amphiphilic substances has caused widespread concerns. In this Perspective, three traditional methods for the stabilization of emulsion droplets according to the type of emulsifiers used are outlined, and the emphasis is placed on the mechanism of steric hindrance for emulsion stabilization. Then, we provide a concise introduction and discussion of the fast interfacial polymerization method as a new strategy for preparing stable emulsifier-free emulsion droplets with a polymer film, including its research background, current progress, and possible development directions. It is anticipated that this paper will promote the development of emulsifier-free emulsion production via fast interfacial polymerization and other related methods.

Uniformly Hybrid Surface Containing Adjustable Hydrophobic/Hydrophilic Components Obtained by Programmed Strain for Synergistic Anti-Icing.

Sufficient efforts have been put into the design of anti-icing materials to eliminate the icing hazard. Among the currently approved anti-icing concepts, hydrophilic/hydrophobic hybrid anti-icing materials inspired by antifreeze proteins show excellent properties in inhibiting ice nucleation, inhibiting ice crystal growth, and reducing ice adhesion. However, it is still a great challenge to accurately regulate the hydrophilic and hydrophobic hybrid components of the coating surface to clarify the synergistic mechanism. This work proposes a strain-manipulated surface modification strategy, and an anti-icing coating with adjustable hydrophilic/hydrophobic hybrid components prepared by combining chemical vapor deposition and siloxane chemistry is obtained. According to the ice resistance experiment at -15 °C, the performance of anti-icing is closely related to the proportion of hydrophilic and hydrophobic hybrids. The icing delay time and ice adhesion strength of the material with the optimal hydrophilic/hydrophobic components are 280 s and 18.6 kPa, respectively. These unique properties can be attributed to the synergistic effect of hydrophilic and hydrophobic structures on the regulation of interfacial water.

Administration of a new nano delivery system coated with Tirofiban to prevent early thrombosis of vein graft.

OBJECTIVE: To verify the administration of a new nano delivery system coated with Tirofiban on preventing early thrombosis in vein graft. METHODS: Forty New Zealand white rabbits were randomly divided into five groups with eight rabbits in each group. The rabbits of all groups underwent jugular vein transplantation, except group I with only neck opening and closing operation. Vein grafts of group II were preprocessed by intravenous injection of normal saline; group III were preprocessed by tirofiban alone; group IV were preprocessed by unloaded nanoparticles of PLGA-PEG; group V were preprocessed by PLGA-PEG coated with tirofiban. Coagulation and platelet function of peripheral and vein graft blood were detected at 1, 2, 4, 12 h and 1, 3, 7, 10, 14 days after operation. Patency rate of vein graft and blood flow index were measured by vascular ultrasound at third, seventh, 10th, and 14th days after operation; two rabbits in each group were randomly sacrificed at the corresponding time of detection. Pathological differences of vein grafts were observed by HE stainin. RESULTS: The patency rate of vein grafts in group V was significantly higher than that in group II to IV. The platelet and platelet aggregation rate in group V were inhibited in vein graft blood significantly. The post-operative PT and APTT in vein graft blood in group V were increased obviously while the FBG, D-dimer and FDP were significantly inhibited. Except group I, the lumen loss rate of vein grafts in group V was significantly lower than that in other groups, and vein graft blood in group V had a significant lower expression of platelet P-selectin and GP IIb/IIIa receptor than that in other groups. CONCLUSION: This study proves that PEG-PLGA coated with tirofiban can effectively prevent early vein graft stenosis from thrombosis by inhibition of platelet function, coagulation function.

Early Braking of Overwarmed Lithium-Ion Batteries by Shape-Memorized Current Collectors.

In the context of the constant impending energy crisis, the lithium-ion battery as a burgeoning energy storage means is showing extraordinary talents in many energy relevant investigations. However, fire and explosion would probably occur when the battery is encountered with overheating, at which the shrinking of the separator routinely causes an internal short circuit. Herein, we develop a kind of novel shape-memorized current collector (SMCC), which can successfully brake battery thermal runaway at the battery internal overheating status. Unlike traditional current collectors made of commercial copper foils, SMCC is made of a micropatterned shape memory micron-sized film with copper deposition. SMCC displays ideal conductivity at normal temperatures and turns to be insulative at overheating temperatures. Following this principle, the battery consisting of an SMCC can run normally at temperatures lower than 90 °C, while it quickly achieves self-shutdown before the occurrence of battery combustion and explosion.

Double Asymmetric Core Optimizes Crystal Packing to Enable Selenophene-based Acceptor with Over 18 % Efficiency in Binary Organic Solar Cells.

Side-chain tailoring is a promising method to optimize the performance of organic solar cells (OSCs). However, asymmetric alkyl chain-based small molecular acceptors (SMAs) are still difficult to afford. Herein, we adopted a novel asymmetric n-nonyl/undecyl substitution strategy and synthesized two A-D1 A'D2 -A double asymmetric isomeric SMAs with asymmetric selenophene-based central core for OSCs. Crystallographic analysis indicates that AYT9Se11-Cl forms a more compact and order intermolecular packing compared to AYT11Se9-Cl, which contributed to higher electron mobility in neat AYT9Se11-Cl film. Moreover, the PM6 : AYT9Se11-Cl blend film shows a better morphology with appropriate phase separation and distinct face-on orientation than PM6 : AYT11Se9-Cl. The OSCs with PM6 : AYT9Se11-Cl obtain a superior PCE of 18.12 % compared to PM6 : AYT11Se9-Cl (17.52 %), which is the best efficiency for the selenium-incorporated SMAs in binary BHJ OSCs. Our findings elucidate that the promising double asymmetric strategy with isomeric alkyl chains precisely modulates the crystal packing and enhances the photovoltaic efficiency of selenophene-incorporated SMAs.

Floating Hydrogel Beads Made by Droplet Impact.

Droplet impact is a ubiquitous natural phenomenon that has been widely utilized to inspire and facilitate many industrial applications. Compared to the widely studied water droplet impact onto identical liquid surfaces, the water droplet impact onto an oil layer floating on a water bath (OLW) receives far less attention and its potential application has never been exploited. Herein, the process of water droplet impact onto the OLW is investigated with emphasis on the metastable states and potential applications. It is found that the dramatic deformation of the oil-water interface caused by the water droplet impact leads to two metastable states: oil in water in oil in water (O/W/O/W) and oil in water in oil (O/W/O). Through the subsequent introduction of gelation process, the metastable states can be frozen into floating hydrogel beads with similar shape to the roly-poly toys, which are attempted in gastric retentive drug delivery and algae bloom control. Specifically, the floating hydrogel beads perform well in gastric retentive drug delivery in vitro due to their inherent slow-release properties and floating capability. In addition, the floating hydrogel beads loading photocatalysts can capture more sunshine, and exhibit high photocatalytic efficiency, which is thus responsible for efficient algae bloom control.

Iodine-Oxidized Diene-Based Rubbers as Anti-icing and Deicing Polymer Coatings.

In an effort to prevent or minimize icing hazards, techniques and materials for icing inhibition and deicing have always been highly favored throughout human history. This work discovers the integrated anti-icing and deicing effects of poly(styrene-b-butadiene-b-styrene) triblock rubber (SBS) after its easy oxidation in iodine vapor. Iodine oxidation happens on the block of polybutadiene, featured by the conversion of SBS from hydrophobic to amphiphilic and the improved capability of photothermal conversion. The oxidized SBS can serve as a polymer coating, which possesses intriguing abilities to delay the kinetics of icing on its surface and repel the ice under light illumination. According to characterizations of surface chemistry and mechanical performance, iodine oxidation is assumed to involve the processes of iodine coordination to unsaturated bonds, the formation of radical cations as a result of the redox reaction between iodine and unsaturated carbon-carbon bonds, improved light absorption owing to the formation of polyiodide anions, and intermolecular coupling of radical cations. The appearance of polar moieties/species within the oxidized SBS is attributed to the delayed ice nucleation. The significant photothermal capacity in visible and near-infrared windows enables the iodine-oxidized SBS coating to remove the adhered ice by melting under light illumination when the icing process is inevitable, even at an extremely low temperature (-25 °C).

Superhydrophilic 2D Covalent Organic Frameworks as Broadband Absorbers for Efficient Solar Steam Generation.

The intrinsic hydrophobicity and limited light absorption especially in the near-infrared (NIR) region of porous organic polymers are two bottlenecks impeding their applications in solar steam generation (SSG). Herein, we develop a 1,4,5,8-tetrakis(phenylamino)anthracene-9,10-dione (TPAD)-based covalent organic framework (COF) (TPAD-COF) featuring both superhydrophilicity and broad light absorption covering from the entire UV/Vis to NIR regions for SSG. TPAD-COF serving as a highly efficient photothermal conversion material without any additives displays an excellent water evaporation of 1.42 kg m-2 h-1 and achieves a high energy conversion efficiency of 94 % under 1 sun irradiation. Further extension of the light absorption range of the TPAD-based COF is realized through post-synthetic modification by chelating BF2 moieties. Systematic control experiments and analysis confirm that the hydrophilicity of photothermal conversion materials plays a more dominant role in the current TPAD-based COFs for SSG.

R-loops mediate transcription-associated formation of human rDNA secondary constrictions.

The ribosomal gene DNA (rDNA) often forms secondary constrictions in the chromosome; however, the molecular mechanism involved remains poorly understood. Here, we report that occurrence of rDNA constriction was increased in the chromosomes in human cancer cell lines compared with normal cells and that decondensed rDNA was significantly enhanced after partial inhibition of rDNA transcription. rDNA transcription was found during the S phase when replication occurred, and thus, DNA replication inhibitors caused constriction formation through hindering rDNA transcription. Inhibition of ataxia ATR (telangiectasia-mutated and RAD3-related) induced rDNA constriction formation. Replication stress or transcription inhibition increased R-loop formation. Topoisomerase I and RNase H1 suppressed secondary constriction formation. These data demonstrate that transcription stress causes the accumulation of stable R-loops (RNA-DNA hybrid) and subsequent constriction formation in the chromosomes.

Three Birds with One Stone: Preventive Protection of Paper Materials by ZnO-PHMB and UV-531 Composite Systems.

As the most frequently used archival materials for painting and recording, paper lays the groundwork for the development of prosperous human civilization. However, its susceptibility to three primary factors including external ultraviolet light, increased acidity, and biological pathogens in long-term storage shortens the longevity of paper. Therefore, the protection of paper-based cultural relics is extremely urgent. Inspired by the three adverse factors affecting the protection of cultural relics, we herein propose to combine the ultraviolet absorber 2-hydroxy-4-(octyloxy)benzophenone (UV-531) and alkaline zinc oxide (ZnO) nanoparticles innovatively into the antibacterial agent polyhexamethylene biguanidine hydrochloride (PHMB) to realize the strategy of three birds with one stone for relics protection. This study illustrates that the tensile strength and the folding endurance of different test papers are guaranteed by coating them with the composite reagents, and molds including Mucor, Trichoderma, and Aspergillus niger are effectually sterilized. In addition, a hand-painted Chinese ink-wash painting with beautiful flowers is chosen as the object for simulating cultural relics protection, and negligible color fading is observed in aging experiments. From the perspective of effectiveness, simplicity, and economy, this strategy sheds light on preservative protection of paper-based relics in long-term storage.

Self-Shaping Microemulsion Gels for Cultural Relic Cleaning.

Cleaning is a foundational and essential operation of protection and restoration of cultural relics, which is also the key step of follow-up works. To overcome the problems of uncontrollable diffusion of cleaning solvents and poor coverage of the cleaning solvent carriers on rough surfaces, here, we propose a strategy of using a self-shaping microemulsion gel that is prepared via emulsifying oleophilic solvents into the specific shear-thinning hydrogel structures. The gel can adaptively cover rough surfaces during the cleaning process coupled with avoidance of unnecessary diffusion of the cleaning solvents, and the mechanical reinforcement of in situ polymerized double-network gels enables its easy peeling off from the surfaces without leaving determinable residues. As a representative demonstration, Paraloid B72, a widely used material for the repair and reinforcement of cultural relics, is employed as a model discolored coating, which can be effectively removed from the rough surface of simulated cultural relics after treatment with the resulting gels. Convincingly, the strategy of constructing agarose/polyacrylamide hybrid double-network gels with shear-thinning and self-shaping performances for the cleaning of cultural relics not only improves the convenience and accuracy of operation but also exhibits an efficient cleaning effect, which will greatly expand the application of microemulsion gels in the cleaning of rough surfaces of cultural relics.

Identification of nucleic acid aptamers against lactate dehydrogenase via SELEX and high-throughput sequencing.

Nucleic acid aptamers are small fragments of DNA or RNA molecules binding specifically to targets, which can be obtained through in vitro screening via systematic evolution of ligands by exponential enrichment (SELEX). Lactate dehydrogenase (LDH) is an important tumor marker, whose level in patients is of great significance for diagnosis of many diseases. Here, we report the identification of LDH aptamers by 9 rounds of screening from a length-mixed single-stranded DNA library using the SELEX technology. After the 3rd and 7th rounds of aptamer screening, affinity was significantly improved, and fluorescence quantitative analysis showed stronger affinity for the aptamers selected from the 7th to 9th rounds of screening. After high-throughput sequencing, motif analysis, and secondary structure prediction, we finally chose and further investigated 15 candidate LDH aptamer sequences with obvious differences in secondary structure in the 7th to 9th rounds of screening. Among them, LDH7-1, LDH7-9, LDH8-2, and LDH9-1 were shown to bind to LDH protein with high affinity and specificity with Kd < 25 nM. This study provides new ideas for rapid detection of LDH protein content and enzyme activity, thus contributing to the development of rapid medical detection.

Effect of pH or Metal Ions on the Oil/Water Interfacial Behavior of Humic Acid Based Surfactant.

Humic acid, a kind of widespread organic macromolecule on earth, is naturally formed through the microbial biodegradation of plant, animal, and microorganism residues. Because of the large number of active functional groups (phenolic hydroxyl and carboxyl), humic acid has been considered as a biocompatible, green, and low-cost biosurfactant recently. In this work, based on the sensitivity of humic acid to the external chemical environment, the oil/water interfacial behavior of sodium humate at different pH or in the presence of metal ions is closely investigated. Sodium humate is significantly enriched toward the oil/water interface at either low pH or high metal-ion concentration to adjust the properties of the prepared emulsion, but the mechanisms are proved to be different when considering the influence of pH and metal ions. Besides, to the best of our knowledge, humic acid based surfactant is proposed as a Pickering emulsifier for the first time, known as solid surfactant. This work promises the great potential of humic acid as a natural environment-responsive surfactant and has important implications for the application of humic acid based surfactant in industry and understanding of the role of humic acid in the natural environment.

A Double-Edged Sword: Complement Component 3 in Toxoplasma gondii Infection.

Sprague Dawley rats and Kunming (KM) mice are artificially infected with type II Toxoplasma gondii strain Prugniaud (Pru) to generate toxoplasmosis, which is a fatal disease mediated by T. gondii invasion of the central nervous system (CNS) by unknown mechanisms. The aim is to explore the mechanism of differential susceptibility of mice and rats to T. gondii infection. Therefore, a strategy of isobaric tags for relative and absolute quantitation (iTRAQ) is established to identify differentially expressed proteins (DEPs) in the rats' and the mice's brains compared to the healthy groups. In KM mice, which is susceptible to T. gondii infection, complement component 3 (C3) is upregulated and the tight junction (TJ) pathway shows a disorder. It is presumed that T. gondii-stimulated C3 disrupts the TJ of the blood-brain barrier in the CNS. This effect allows more T. gondii passing to the brain through the intercellular space.

Metformin treatment alleviates polycystic ovary syndrome by decreasing the expression of MMP-2 and MMP-9 via H19/miR-29b-3p and AKT/mTOR/autophagy signaling pathways.

In this study, we aimed to investigate the molecular pathway(s) underlying the effect of metformin (MET) on the expression of matrix metalloproteinase (MMP)-2 and MMP-9. Real-time polymerase chain reaction, Western blot analysis, and gelatin zymography were used to assay the effects of MET on MMP and AMPK signaling pathways. In addition, HTOG cells were treated with miR-29b-3p/a scramble control, H19/a negative control, or MET/PBS to explore possible signaling pathway(s) underlying the inhibitory effect of MET on MMP-2/MMP-9. A rat model of polycystic ovary syndrome (PCOS) was also established to validate the molecular mechanism(s) of MET in vivo. The administration of MET suppressed the expression of MMP-9/MMP-2 and mTOR while increasing the expression of Akt and AMPK, indicating that MET reduced the expression of MMPs via the AMPK signaling pathway. Meanwhile, the H19/miR-29b-3p/MMP-9 and H19/miR-29b-3p/MMP-2 signaling pathways were implicated in PCOS, in which the interactions between H19/miR-29b-3p and MMP-9/MMP-2/miR-29b-3p were confirmed. Furthermore, the administration of MET suppressed the expression of H19 while elevating the expression of miR-29b-3p. And the role of MET in PCOS was also confirmed in vivo via examining the activity of H19 and AMPK signaling pathways in cell or serum samples collected from PCOS rats. MET exhibits a therapeutic effect in the treatment of PCOS by reducing the expression of MMPs.