Stretch-Induced Conductivity Enhancement in Highly Conductive and Tough Hydrogels.

The resistance of gels and elastomers increases significantly with tensile strain, which reduces conductive stability and restricts their use in stable and reliable electronics. Here, highly conductive tough hydrogels composed of silver nanowires (AgNWs), liquid metal (LM), and poly(vinyl alcohol) (PVA) are fabricated. The stretch-induced orientations of AgNWs, deformable LM, and PVA nanocrystalline create conductive pathways, enhancing the mechanical properties of the hydrogels, including increased ultimate fracture stress (13-33 MPa), strain (3000-5300%), and toughness (390.9-765.1 MJ m-3 ). Notably, the electrical conductivity of the hydrogels is significantly improved from 4.05 × 10-3 to 24 S m-1 when stretched to 4200% strain, representing a 6000-fold enhancement. The incorporation of PVA nanocrystalline, deformable LM, and AgNWs effectively mitigates stress concentration at the crack tip, thereby conferring crack propagation insensitivity and fatigue resistance to the hydrogels. Moreover, the hydrogels are designed with a reversible crosslinking network, allowing for water-induced recycling.

Circ_0079471 Regulates the Proliferation, Migration, Invasion and Apoptosis of Osteosarcoma Cells by Mediating miR-485-3p and TRIP6.

BACKGROUND: Circular RNAs (circRNAs) are a special class of non-coding RNA molecules that show a closed circular structure and have been implicated in both tumour formation and oncogenesis. OBJECTIVE: This study aimed to learn more about how circ_0079471 functions in osteosarcomas (OSs). METHOD: Quantitative real-time polymerase chain reaction was used to detect the expression levels of thyroid hormone receptor-interacting protein 6 (TRIP6), miR-485-3p and circ_0079471. Methyl-thiazolyl-tetrazolium and flow cytometry were used to track cell growth and cell-cycle progression, and the research explored wound healing (migration) and invasion using Transwell plates. Western blotting was used to determine the protein expression of TRIP6, proliferating cell nuclear antigen and cyclin D1, and a dual-luciferase assay revealed the target relationship. RESULT: A xenograft experiment evaluated the in vivo effects of circ_0079471 on OS, and the results revealed the high expression of circ_0079471 in OS tissue and cells. The proliferation, cell-cycle migration and invasion of cells were reduced after circ_0079471 knockdown in OS cells; however, the effects of this knockdown were reversed when TRIP6 was overexpressed in the OS cells. The function of circ_0079471 was also achieved by in vivo miR-485-3p sponging. The upregulation of miR-485-3p and the downregulation of TRIP6 partly resulted in circ_0079471 downregulation, which subsequently inhibited OS progression. CONCLUSION: According to these results, circ_0079471 influences the development of OS by regulating miR-485-3p and TRIP6.

Low-Hysteresis and High-Toughness Hydrogels Regulated by Porous Cationic Polymers: the Effect of Counteranions.

Service life and range of polymer materials is heavily reliant on their elasticity and mechanical stability under long-term loading. Slippage of chain segments under load leads to significant hysteresis of the hydrogels, limiting its repeatability and mechanical stability. Achieving the desired elasticity exceeding that of rubber is a great challenge for hydrogels, particularly when subjected to large deformations. Here, low-hysteresis and high-toughness hydrogels were developed through controllable interactions of porous cationic polymers (PCPs) with adjustable counteranions, including reversible bonding of PCP frameworks/polymer segments (polyacrylamide, PAAm) and counteranions/PAAm. This strategy reduces chain segment slippage under load, endowing the PCP-based hydrogels (PCP-gels) with good elasticity under large deformations (7 % hysteresis at a strain ratio of 40). Furthermore, due to the enlarged chain segments entanglement by PCP, the PCP-gels exhibit large strain (13000 %), significantly enhanced toughness (68 MJ m-3 ), high fracture energy (43.1 kJ m-2 ), and fatigue resistance. The unique properties of these elastic PCP-gels have promising applications in the field of flexible sensors.

Poly(Ionic Liquid) Double-Network Elastomers with High-Impact Resistance Enhanced by Cation-π Interactions.

With the continuous development of impact protection materials, lightweight, high-impact resistance, flexibility, and controllable toughness are required. Here, tough and impact-resistant poly(ionic liquid) (PIL)/poly(hydroxyethyl acrylate) (PHEA) double-network (DN) elastomers are constructed via multiple cross-linking of polymer networks and cation-π interactions of PIL chains. Benefiting from the strong noncovalent cohesion achieved by the cation-π interactions in PIL chains, the prepared PIL DN elastomers exhibit extraordinary compressive strength (95.24 ± 2.49 MPa) and toughness (55.98 ± 0.66 MJ m-3) under high-velocity impact load (5000 s-1). The synthesized PIL DN elastomer combines strength and flexibility to protect fragile items from impact. This strategy provides a new research idea in the field of the next generation of safety and protective materials.

Supramolecular Ionogels Tougher than Metals.

Common natural and synthetic high-strength materials (such as rubber, plastics, ceramics, and metals) undergo the occurrence of poor deformability. Achieving high strength and large deformation simultaneously is a huge challenge. Herein, high-strength ionogels are developed through the synergy of force-induced crystallization and halometallate ionic liquid created supramolecular ionic networks. The prepared poly(vinyl alcohol)/halometallate ionic liquid ionogels show excellent mechanical properties, including ultimate fracture stress (63.1 ± 2.1 MPa), strain (5248 ± 113%), and unprecedented toughness (1947 ± 52 MJ m-3 ), which is much higher than that of most metals and alloys. Furthermore, the ionogels can achieve reversibility by water to realize green recovery and restoration of damaged mechanical properties.

Nitric oxide-releasing poly(ionic liquid)-based microneedle for subcutaneous fungal infection treatment.

Poor permeation of therapeutic agents and similar eukaryotic cell metabolic and physiological properties of fungi and human cells are two major challenges that lead to the failure of current therapy for fungi-induced skin and soft tissue infections. Herein, a nitric oxide (NO)-releasing poly(ionic liquid)-based microneedle (PILMN-NO) with the capacity of deep persistent NO toward subcutaneous fungal bed is presented as a synergistic antifungal treatment strategy to treat subcutaneous fungal infection. Upon the insertion of PILMN-NO into skin, the contact fungicidal activities induced by electrostatic and hydrophobic effects of poly(ionic liquid) and the released NO sterilization resulting from the peroxidation and nitrification effect of NO achieved enhanced antifungal efficacy against fungi (Candida albicans) both in vitro and in vivo. Simultaneously, PILMN-NO showed biofilm ablation ability and efficiently eliminated mature biofilms. In vivo fungal-induced subcutaneous abscess studies revealed that PILMN-NO could effectively sterilize fungi while suppressing the inflammatory reaction, facilitating collagen deposition and angiogenesis, and promoting wound healing. This work provides a new strategy to overcome the difficulties in deep skin fungal infection treatment and has potential for further exploitation of NO-releasing microbicidal therapy.

Realizing an Ultrahigh Depolarization Temperature near the Curie Point and Large d33 with Superior Temperature Stability in Lead-Free Ceramics via a Sandwich Structure Design.

An imminent challenge of lead-free Bi0.5Na0.5TiO3-based (BNT) piezoceramics is that the giant piezoelectric constant (d33) caused by the morphotropic phase boundary is incompatible with a high depolarization temperature (Td) and ultralow temperature coefficient (Ttc) of the real-time d33, which severely hinders their industrial application in the field of elevated temperatures. Herein, a sandwich-structured 0.94Bi0.5Na0.5TiO3-0.06BaTiO3/0.89Bi0.5Na0.5TiO3-0.11BaTiO3/0.94Bi0.5Na0.5TiO3-0.06BaTiO3 (SWS-6/11/6BT-y, where y refers to the weight fraction of the BNT-11BT solid solution) ceramic composite is engineered for mitigating the conflict between d33, Td and Ttc. Following this strategy, ultrahigh Td near the Curie point (225 °C, close to that of the BNT-11BT layer) and relatively large d33 (130 pC/N, close to that of the BNT-6BT layer) are simultaneously realized in a SWS-6/11/6BT-40%-Q ceramic composite. More importantly, the ultralow Ttc (0.07%) of real-time d33 is also achieved in this work. The structural heterogeneity yields the high piezoresponse, and the built-in field resulting from layer-type ceramic composites provides the driving force to promote the diffused ferroelectric-relaxor phase transition and the resultant ferroelectric order with high Td. The above synergistic contributions realize the remission of the d33-Td-Ttc conflict in a sandwich-structural SWS-6/11/6BT-40% ceramic composite. Thus, our work provided a path for designing the BNT-based piezoceramics with potential for industrial applications.

Ultra-Tough and Recyclable Ionogels Constructed by Coordinated Supramolecular Solvents.

The mechanical properties of most hydrogels (ionogels) are considerably affected by covalently cross-linked networks. However, the interactions between solvent/solvent molecules and solvent/polymer chains are usually ignored. Herein, a series of ultra-tough ionogels were prepared via a supramolecular solvent, halometallate ionic liquid, in which cations and coordinating anions form a 3D supramolecular network. The linear polymer chains are physically cross-linked with supramolecular solvents synergistically enhancing the strength (14.3 MPa), toughness (78 MJ m-3 ), and Young's modulus (55 MPa) of ionogels, effectively dispersing the stress concentration under load, and obtaining better fatigue resistance and higher fracture energy (198 kJ m-2 ). Furthermore, the reversible cross-linking enables green recovery and recycling of ionogels, simply by water. This strategy shows broad applicability based on a variety of supramolecular solvents and coordinatable polymers.

Three-Dimensional Printable, Highly Conductive Ionic Elastomers for High-Sensitivity Iontronics.

The development of hydrogels and ionic gels for applications in fields such as soft electronics and wearable sensors is limited by liquid evaporation or leakage. Ionic conductors without volatile liquids are better choices for flexible and transparent devices. Here, a liquid polymer electrolyte (LPE) is prepared from a mixture of lithium bis(trifluoromethane)sulfonimide and polyethylene glycol (PEG) above the melting point of PEG. A three-dimensional (3D) printable solvent-free ionic elastomer (IE) is introduced by photopolymerization of ethyl acrylate and hydroxyethyl acrylate in the prepared LPE. The conductivity is significantly improved by the presence of a high content of the lithium salt. Dynamic cross-linking networks improve the stretchability and resilience of the elastomer. The pattern design capability of the IE is provided by light-curing 3D printing. These features demonstrate that the IE has broad application prospects in flexible sensors, ion skins, and soft robots.

Comparison of the clinical efficacy of percutaneous transforaminal endoscopic discectomy and traditional laminectomy in the treatment of recurrent lumbar disc herniation.

ABSTRACT: A few years ago, percutaneous transforaminal endoscopic discectomy (PTED) began to prevail in clinical treatment of recurrent lumbar disc herniation (RLDH), whereas traditional laminectomy (TL) was treated earlier in RLDH than PTED. This study aimed to compare the clinical efficacy of PTED and TL in the treatment of RLDH.Between November 2012 and October 2017, retrospective analysis of 48 patients with RLDH who were treated at the Cancer Hospital, Chinese Academy of Sciences, Hefei and Department of Orthopaedics, Second Affiliated Hospital of Anhui Medical University. Perioperative evaluation indicators included operation time, the intraoperative blood loss, length of incision and hospitalization time. Clinical outcomes were measured preoperatively, and at 1 days, 3 months, and 12 months postoperatively. The patients' lower limb pain was evaluated using Oswestry disability index (ODI) and visual analog scale (VAS) scores. The ODI is the most widely-used assessment method internationally for lumbar or leg pain at present. Every category comprises 6 options, with the highest score for each question being 5 points. higher scores represent more serious dysfunction. The VAS is the most commonly-used quantitative method for assessing the degree of pain in clinical practice. The measurement method is to draw a 10 cm horizontal line on a piece of paper, 1 end of which is 0, indicating no pain, which the other end is 10, which means severe pain, and the middle part indicates different degree of pain.Compared with the TL group, the operation time, postoperative bed-rest time, and hospitalization time of the PTED group were significantly shorter, and the intraoperative blood loss was also reduced. These differences were statistically significant (P < .01). There were no significant differences in VAS or ODI scores between the two groups before or after surgery (P > .05).PTED and TL have similar clinical efficacy in the treatment of RLDH, but PTED can shorten the operation time, postoperative bed-rest time and hospitalization time, and reduce intraoperative blood loss, so the PTED is a safe and effective surgical method for the treatment of RLDH than TL, but more randomized controlled trials are still required to further verify these conclusions.

TRIP6 regulates the proliferation, migration, invasion and apoptosis of osteosarcoma cells by activating the NF-κB signaling pathway.

Thyroid hormone receptor-interacting protein 6 (TRIP6), a member of the zyxin family of Lin-Isl-Mec (LIM) proteins, is an adaptor protein primarily expressed in epithelial cells. TRIP6 can regulate a variety of cellular responses, such as actin cytoskeletal reorganization and cell adhesion. However, to the best of our knowledge, the role of TRIP6 in osteosarcoma (Os) has not been previously reported. Therefore, the present study investigated the role of TRIP6 in the occurrence and development of Os, and the potential of utilizing TRIP6 as a therapeutic target in Os. The present results suggested that the expression levels of TRIP6 were significantly increased in Os cells and clinical tissue specimens compared with normal osteoblasts and adjacent non-tumor tissue. Moreover, the present results suggested that overexpressing TRIP6 significantly increased proliferation, migration and invasion, while inhibiting apoptosis in Os cells. However, silencing TRIP6 decreased proliferation, migration and invasion, while activating apoptosis in Os cells. The present results suggested that overexpression of TRIP6 increased NF-κB activation by decreasing the protein expression levels of inhibitor of κBα, and increasing total and phosphorylated P65 levels. The present results indicated that TRIP6 silencing decreased NF-κB activation. Collectively, the present results suggested that TRIP6 may play a role in promoting Os cell proliferation, migration and invasion, while inhibiting cell apoptosis. Furthermore, TRIP6 may be utilized as a novel prognostic biomarker and therapeutic target in Os.

Clinical efficacy of percutaneous transforaminal endoscopic discectomy in treating adolescent lumbar disc herniation.

Ten years ago, endoscopic techniques began to prevail in clinical treatment of lumbar disc herniation (LDH), but to date, few studies have reported the clinical efficacy of percutaneous transforaminal endoscopic discectomy (PTED) in treating adolescent LDH. This study aimed to evaluate the surgical outcomes of PTED in treating adolescent patients with LDH.Between June 2012 and June 2016, retrospective analysis of 43 adolescent patients diagnosed with single-segment LDH at spine surgery at the Second Affiliated Hospital of Anhui Medical University. The patients' lower limb pain was evaluated using visual analogue scale (VAS) scores and the Oswestry Disability Index (ODI). The VAS is the most commonly-used quantitative method for assessing the degree of pain in clinical practice. The measurement method is to draw a 10 cm horizontal line on a piece of paper, 1 end of which is 0, indicating no pain, while the other end is 10, which means severe pain, and the middle part indicates different degrees of pain. The clinician then asks the patient to make a mark on the line to indicate the degree of pain based on how he or she feels. The ODI is the most widely-used assessment method internationally for lumbar or leg pain at present. The ODI questionnaire is composed of 10 questions, covering pain intensity, independent living, carrying, walking, sitting, standing, sleep, travel, sex, and social life. Every category comprises 6 options, with the highest score for each question being 5 points. Thus the 1st option is worth 0 points, the last option scores 5 points, and higher scores represent more serious dysfunction. Patient satisfaction was evaluated using the modified MacNab score. Clinical outcomes were measured preoperatively, and at 3 days, 6 months, and 12 months postoperatively.All 43 patients were followed up for 12 to 24 months. The average follow-up time was 18.33 months. The VAS scores and ODI scores at 3 days, 6 months, and 12 months postoperatively were significantly lower than before surgery. The difference was statistically significant (P < .001). The differences in VAS scores and ODI scores at 3 days, 6 months, and 12 months after surgery were also statistically significant (P < .001). According to the modified MacNab criteria, 26 cases were rated excellent, 14 cases were good, and 3 cases were acceptable at the final follow-up, and 93.02% of these patients had excellent outcomes.The PTED is an effective and safe surgical method for the treatment of adolescent patients with LDH, but high-quality randomized controlled trials are still required to further verify these findings.

Association between NKX2-5 rs29784 and infantile hypertrophic pyloric stenosis in Chinese Han population.

PURPOSE: The aim of this study was to evaluate the association of three single nucleotide polymorphisms (SNPs, rs11712066 and rs573872 near MBNL1, rs29784 near NKX2-5) with infantile hypertrophic pyloric stenosis (IHPS) in Chinese Han population. METHODS: A total of 47 family trios consisting of infants with IHPS and their healthy biological parents were recruited for this study. Genotypes were determined using direct sequencing. Transmission disequilibrium test (TDT) was performed for family-based association analysis. RESULTS: Genotypic distributions of three SNPs in both groups (patients and proband's parents) were in conformity with Hardy-Weinberg equilibrium (P > 0.05). There were significant preferential transmission of A allele of rs29784 from the parents to affected offspring (TDT: x(2) = 5.444, P = 0.0196). However, other two polymorphism loci (rs11712066 and rs573872) were not significant susceptibility loci for IHPS in Chinese Han population. CONCLUSIONS: We found that there was a significant association between rs29784 and IHPS.

The clinical features of infantile hypertrophic pyloric stenosis in Chinese Han population: analysis from 1998 to 2010.

OBJECTIVE: To investigate clinical features of infantile hypertrophic pyloric stenosis (IHPS) in Chinese Han population. METHODS: Three hundred and sixteen hospitalized patients with IHPS from January 1998 to February 2010 were retrospectively reviewed, and data including patient's sex, onset age, other coexisting congenital defects, pyloric circular muscle thickness evaluated by ultrasonograph, serum electrolytes concentration, and results of arterial blood gas analysis on admission were collected. The patients were divided into two groups: the duration between first onset and admission less than or equal to 10 days (early onset group), and more than 10 days (late onset group). The results of arterial blood gas and serum electrolyte concentration were compared between the two groups. RESULTS: There were 271 males and 45 females in 316 patients; the onset age ranged between 1 and 351 (26.5±26.6) days. The birth weight ranged between 1.6 and 4.5 (3.23±0.44) kilograms; coexisting congenital defects were found in 65 cases (20.6%). Pyloric circular muscle thickness was 4-8 (5.4±1.0) millimetres (mm). For the early onset group, the rates of hypokalemia, hypochloraemia and hypercapnia were significantly lower than those in the late onset group (18.67% VS 50%, P<0.0001; 46.03% VS 71.01%, P = 0.003; 56.58% VS 83.44%, P = 2.17×10(-5); respectively). CONCLUSIONS: The symptom duration in Chinese Han population was longer than that in other populations. And as the prolongation of symptom duration, the incidence of acid-base imbalance increased significantly. Infants with persistent vomiting at the age of 3∼5 weeks after birth should be considered IHPS, and go to hospital as soon as possible in order to reduce the incidence of hypokalemia, hypochloraemia and hypercapnia, and avoid deterioration.

Osteodifferentiation of mesenchymal stem cells on chitosan/hydroxyapatite composite films.

Chitosan (Ch) is one of the most commonly used natural biomaterials. Osteodifferentiation of mesenchymal stem cells (MSCs) on Ch has drawn extensive interest. Hydroxyapatite (HA) is a component of skeleton and teeth with good biocompatibility. Combination with HA may be a good method to modify Ch to facilitate cellular behaviors and functions on it. In this study, Ch/HA film was prepared and characterized. Its potential to benefit cellular behaviors and osteodifferentiation of MSCs was evaluated. Resultantly, physical properties of composite Ch/HA, including water-in-air contact angle, tensile strength, elastic modulus, and breaking elongation were favorably modified. In cellular culture medium, Ch/HA films absorbed more Ca(2+) than Ch films, and more HA crystalline growths on Ch/HA films. 3-(4,5-Dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and morphological features showed better proliferation and adhesion of MSCs on Ch/HA films. Osteodifferentiation of MSCs on Ch/HA was promoted, indicated by modified transcription level of osteocalcin, osteopontin, collagen I, alkaline phosphatase (ALP), and induced ALP activity. These data suggest biocompatibility of Ch is modified after being blended with HA, which promotes osteodifferentiation of MSCs. This can be a promising approach to modify Ch for its applications in bone tissue engineering.

[Application of functional quantum dots in cancer diagnosis and therapy: a review].

Quantum dots (QDs) are nanometer-sized luminescent semiconductor nanocrystals. Their unique optical properties, such as high brightness, long-term stability, simultaneous detection of multiple signals and tunable emission spectra, make them appealing as potential diagnostic and therapeutic systems in oncology. Preparing the functional QDs by modifying bio-molecules such as antibody will have potential value for cancer diagnosis and treatment. This paper summarized the recent progress of promising application of QDs in cancer diagnosis and therapy, from identifying molecular targets, to drug delivery and therapy; from limitations of toxicity issues related to QDs in living organisms to multifunctional design and development. Finally, the promising applications of QDs are also discussed.

Increasing anticancer drug internalization induced by new Au-MWCNTs nanocomposite.

Multi-walled carbon nanotubes (MWCNTs) are found to hold promise in wide range of applications due to their well-known unique properties. However, their applications in biomedicine are still limited by the relative cytotoxicity. In this study, we introduce the biocompatible gold nanoparticles (Au NPs) modified on MWCNTs, forming new stable nanocomposites: Au-MWCNTs. Further, we design a strategy to explore their drug delivery applications and anti-tumor effects by combining with daunorubicin (DNR), using human hepatocarcinoma cells (SMMC-7721 cells) as cancer cells model. Our results show better biocompatibility of Au-MWCNTs than that of MWCNTs. Moreover, compared with DNR treatment alone, when cells treated by Au-MWCNTs together with DNR, obviously increased DNR concentrations in SMMC-7721 cells and anticancer functions are found, which indicates that Au-MWCNTs could be well qualified for efficient delivery carrier importing anticancer agents like DNR into target cells. This strategy develops an avenue to lessen the toxic side-effect of delivery carrier and thus as the promising approach in relevant cancer therapy.

Photodynamic effect of mesoporous material: titanium dioxide whiskers on SMMC-7721 cells.

In this report, we have fabricated a novel nanomaterial, titanium dioxide whiskers (TiO2Whs), and evaluate its photodynamic characters on Rhodamine B, where TiO2Whs exhibit better photocatalytic activity than titanium dioxide nanoparticles (TiO2NPs). After testing the biocompatibility, we further investigated the effects of TiO2Whs on human hepatocarcinoma cells (SMMC-7721 cells) under UV illumination from cell level, concentration-dependent effect level, time-dependent effect level, and finally genomic apoptosis level. Our results showed that TiO2Whs possess more obviously photo-killing effect on cancer cells compared with that of TiO2NPs. These studies implied that the novel nanomaterial, TiO2Whs, could be utilized as a promising biomedical agent and would have enormous potential application in photodynamic therapy for cancer treatment in the future.