Bioinspired Interfacial Materials with Enhanced Drop Mobility: From Fundamentals to Multifunctional Applications.

The development of bioinspired interfacial materials with enhanced drop mobility that mimic the innate functionalities of nature will have a significant impact on the energy, environment and global healthcare. Despite extensive progress, state of the art interfacial materials have not reached the level of maturity sufficient for industrial applications in terms of scalability, stability, and reliability. These are complicated by their operating environments and lack of facile approaches to control the local structural texture and chemical composition at multiple length scales. The recent advances in the fundamental understanding are reviewed, as well as practical applications of bioinspired interfacial materials, with an emphasis on the drop bouncing and coalescence-induced jumping behaviors. Perspectives on how to catalyze new discoveries and to foster technological adoption to move this exciting area forward are also suggested.

Surface guided radiation therapy with an innovative open-face mask and mouth bite: patient motion management in brain stereotactic radiotherapy.

INTRODUCTION: To guarantee treatment reproducibility and stability, immobilization devices are essential. Additionally, surface-guided radiation therapy (SGRT) serves as an accurate complement to frameless stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) by aiding patient positioning and real-time monitoring, especially when non-coplanar fields are in use. At our institute, we have developed a surface-guided SRS (SG-SRS) workflow that incorporates our innovative open-face mask (OM) and mouth bite (MB) to guarantee a precise and accurate dose delivery. METHODS: This study included 40 patients, and all patients were divided into closed mask (CM) and open-face mask (OM) groups according to different positioning flow. Cone beam computed tomography (CBCT) scans were performed, and the registration results were recorded before and after the treatment. Then Bland-Altman method was used to analyze the consistency of AlignRT-guided positioning errors and CBCT scanning results in the OM group. The error changes between 31 fractions in one patient were recorded to evaluate the feasibility of monitoring during treatment. RESULTS: The median of translation error between stages of the AlignRT positioning process was (0.03-0.07) cm, and the median of rotation error was (0.20-0.40)°, which were significantly better than those of the Fraxion positioning process (0.09-0.11) cm and (0.60-0.75)°. The mean bias values between the AlignRT guided positioning errors and CBCT were 0.01 cm, - 0.07 cm, 0.03 cm, - 0.30°, - 0.08° and 0.00°. The 31 inter-fractional errors of a single patient monitored by SGRT were within 0.10 cm and 0.50°. CONCLUSIONS: The application of the SGRT with an innovative open-face mask and mouth bite device could achieve precision positioning accuracy and stability, and the accuracy of the AlignRT system exhibits excellent constancy with the CBCT gold standard. The non-coplanar radiation field monitoring can provide reliable support for motion management in fractional treatment.

Analysis of Individualized Silicone Rubber Bolus Using Fan Beam Computed Tomography in Postmastectomy Radiotherapy: A Dosimetric Evaluation and Skin Acute Radiation Dermatitis Survey.

Objective: To investigate the dosimetric effects of using individualized silicone rubber (SR) bolus on the target area and organs at risk (OARs) during postmastectomy radiotherapy (PMRT), as well as evaluate skin acute radiation dermatitis (ARD). Methods: A retrospective study was performed on 30 patients with breast cancer. Each patient was prepared with an individualized SR bolus of 3 mm thickness. Fan-beam computed tomography (FBCT) was performed at the first and second fractions, and then once a week for a total of 5 times. Dosimetric metrics such as homogeneity index (HI), conformity index (CI), skin dose (SD), and OARs including the heart, lungs, and spinal cord were compared between the original plan and the FBCTs. The acute side effects were recorded. Results: In targets' dosimetric metrics, there were no significant differences in Dmean and V105% between planning computed tomography (CT) and actual treatments (P > .05), while the differences in D95%, V95%, HI, and CI were statistically significant (P < .05). In OARs, there were no significant differences between the Dmean, V5, and V20 of the affected lung, V5 of the heart and Dmax of the spinal cord (P > .05) except the V30 of affected lung, which was slightly lower than the planning CT (P < .05). In SD, both Dmax and Dmean in actual treatments were increased than plan A, and the difference was statistically significant (P < .05), while the skin-V20 and skin-V30 has no difference. Among the 30 patients, only one patient had no skin ARD, and 5 patients developed ARD of grade 2, while the remaining 24 patients were grade 1. Conclusion: The OR bolus showed good anastomoses and high interfraction reproducibility with the chest wall, and did not cause deformation during irradiation. It ensured accurate dose delivery of the target and OARs during the treatment, which may increase SD by over 101%. In this study, no cases of grade 3 skin ARD were observed. However, the potential of using OR bolus to reduce grade 1 and 2 skin ARD warrants further investigation with a larger sample size.

Development and Characterization of Multifunctional Wound Dressing with the Property of Anti-bacteria and Angiogenesis.

Overcoming the bacterial infection and promoting angiogenesis are challenge and imperious demands in wound healing and skin regeneration. Hereby, we developed a multifunctional AMP/S1P@PLA/gelatin wound dressing fabricated by electrospinning poly (L-lactic acid) (PLA)/gelatin with antimicrobial polypeptides (AMPs) and sphingosine-1-phosphate (S1P) in order to inhibit the bacteria growth and induce angiogenesis. In our work, AMP/S1P@PLA/gelatin wound dressing was obtained by two-step method of electrospinning and dopamine adsorption. Our results showed that incorporating AMP into PLA/gelatin nanofibrous membranes significantly improved antibacterial properties against both Escherichia coli and Staphylococcus aureus. S1P releasing from AMP/S1P@PLA/gelatin nanofibrous membranes could significantly enhance tube formation. Simultaneously, we found that the AMP/S1P@PLA/gelatin nanofibrous membranes facilitated the adhesion, proliferation, and migration of human umbilical vein endothelial cells (HUVECs) and murine fibroblast (L929). AMP/S1P@PLA/gelatin membranes could also accelerate infected wound healing and skin regeneration by antibacterial and pro-angiogenesis effects. In summary, our developed AMP/S1P@PLA/gelatin nanofibrous membranes could be multifunctional dressing for infected wound healing and skin regeneration. Schematic figure to describe the characterizations and preparation of AMP/S1P@PLA/gelatin nanofibrous membranes.

Enzyme-triggered self-assembly of a small molecule: a supramolecular hydrogel with leaf-like structures and an ultra-low minimum gelation concentration.

We report on the use of a phosphatase to assist the formation of leaf-like structures and a supramolecular hydrogel with an ultra-low minimum gelation concentration. The compound can gel water at a minimum gelation concentration of 0.01 wt%, which is the lowest gelation concentration reported up to now. The images obtained by transmission electron microscopy (TEM) reveal the existence of leaf-like structures serving as the matrix of the hydrogels. The stability of the hydrogels was studied and emission spectra were used to get information about the molecular packing in the leaf-like structures. Since lowering the concentration of the gelator decreases the toxicity of the resulting hydrogels, ultra-low concentration gels have potential uses as biocompatible biomaterials for, e.g., cell cultures, tissue engineering, and drug delivery.

Preparation and characterization of PEG-modified polyurethane pressure-sensitive adhesives for transdermal drug delivery.

BACKGROUND: The purpose of this work was to develop novel pressure-sensitive adhesives (PSAs) for transdermal drug-delivery systems (TDDS) with proper adhesive properties, hydrophilicity, biocompatibility and high drug loading. METHOD: Polyethyleneglycol-modified polyurethane PSAs (PEG-PU-PSAs) were synthesized by prepolymerization method with PEG-modified co-polyether and hexamethylene diisocyanate. The effects of reaction temperature, catalyst, ratios of NCO/OH, co-polyether composition, and chain extender were investigated. Drug loading was studied by using thiamazole (hydrophilic drug), diclofenac sodium (slightly hydrophilic drug), and ibuprofen (lipophilic drug) as model drugs. In vitro drug-release kinetics obtained with Franz diffusion cell and dialysis membrane. RESULTS: The results showed that when reaction temperature at 80 degrees C, weight percentage of stannous octoate as catalyst at 0.05%, ratio of NCO/OH at 2.0-2.2, ratio of PEG/polypropylene glycol (PPG)/polytetramethylene ether glycol (PTMG) at 30/25-30/50-55, and weight percentage of glycol as chain extender at 4.5%, PEGPU-PSAs synthesized performed well on adhesive properties. Actually, PEG on the main chain of the PU could improve the hydrophilicity of PSAs, whereas PPG and PTMG could offer proper adhesive properties. Skin compatibility test on volunteers indicated that PEG-PU-PSAs would not cause any skin irritations. All the model drugs had excellent stabilizations in PEG-PU-PSAs. In vitro drug-release kinetics demonstrated that the drug release depended on drug-loading level and solubility of the drug. CONCLUSION: These experimental results indicated that PEG-PU-PSAs have good potential for applications in TDDS.

Biocompatibility evaluation of silk fibroin with peripheral nerve tissues and cells in vitro.

Silk-based materials have been used in the field of bone or ligament tissue engineering. In order to explore the feasibility of using purified silk fibroin to construct artificial nerve grafts, it is necessary to evaluate the biocompatibility of silk fibroin material with peripheral nerve tissues and cells. We cultured rat dorsal root ganglia (DRG) on the substrate made up of silk fibroin fibers and observed the cell outgrowth from DRG during culture by using light and electron microscopy coupled with immunocytochemistry. On the other hand, we cultured Schwann cells from rat sciatic nerves in the silk fibroin extract fluid and examined the changes of Schwann cells after different times of culture. The results of light microscopy, MTT test and cell cycle analysis showed that Schwann cells cultured in the silk fibroin extract fluid showed no significant difference in their morphology, cell viability and proliferation as compared to that in plain L15 medium. Furthermore, no significant difference was found in expression of the factors secreted by Schwann cells, such as nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and S-100, between Schwann cells cultured in the silk fibroin extraction fluid and in plain L15 medium by the aid of immunocytochemistry, RT-PCR and Western analysis. Collectively, these data indicate that silk fibroin has good biocompatibility with DRG and is also beneficial to the survival of Schwann cells without exerting any significant cytotoxic effects on their phenotype or functions, thus providing an experimental foundation for the development of silk fibroin as a candidate material for nerve tissue engineering applications.

Procalcitonin sensitive detection based on graphene-gold nanocomposite film sensor platform and single-walled carbon nanohorns/hollow Pt chains complex as signal tags.

Septicemia is a serious disease that requires early diagnosis, and procalcitonin (PCT) serves as a diagnostic biomarker for this disease. Traditional clinical detection (via immune-gold chips) remains difficult and expensive. An electrochemical immunosensor based on new nanomaterials may provide a solving approach. Herein, an ultrasensitive sandwich electrochemical strategy for PCT detection was developed. Firstly, reduced graphene oxide (rGO)-gold (Au) nano-composite film was used as the immunosensor platform to increase the amount of PCT antibody 1(Ab1) immobilized. Next, single-walled carbon nanohorns (SWCNHs)/hollow Pt chains (HPtCs) complex was firstly utilized to label PCT Ab2 as signal tags. For SWCNHs with few side effects, high surface area and HPtCs with higher specific surface, better catalytic activity, complex synthesized from both may provide more advantages. Moreover, to amplify signal, HPtC catalytic activity with H2O2 was enhanced by horseradish peroxidase (HRP) for dual synergy amplification. The whole results demonstrated that the proposed immunosensor exhibited fast operation, high sensitivity, good reproducibility, acceptable stability and ideal selectivity compared with traditional method. The linear calibration of the immunosensor ranged from 1.00 pg/mL to 2.00 × 10(1)ng/mL with a detection limit of 0.43 pg/mL. Analytical application results revealed that the immunosensor matched with the real concentrations of serum samples. Overall this immunosensor may provide a new alternative strategy for PCT detection.

Sodium fluoride activates ERK and JNK via induction of oxidative stress to promote apoptosis and impairs ovarian function in rats.

The toxicity of sodium fluoride (NaF) to female fertility is currently recognized; however, the mechanisms are unclear. Previously, we reported a reduction in successful pregnancy rates, ovarian atrophy and dysfunction following exposure to NaF. The purpose of this study was to elucidate the underlying molecular mechanisms. Female Sprague-Dawley rats (10 rats/group) received 100 or 200mg/L NaF in their drinking water for 6 months or were assigned to an untreated control group. Apoptotic indices and oxidative stress indicators in blood and ovarian tissue were analyzed following sacrifice. The results confirmed the NaF-induced ovarian apoptosis, with concomitant activation of oxidative stress. Further investigations in ovarian granular cells showed that exposure to NaF activated extracellular regulated protein kinase (ERK) and c-Jun NH2 kinase (JNK), disrupting the ERK and JNK signaling pathways, while p38 and PI3K remained unchanged. These data demonstrated that oxidative stress may play a key role in NaF-induced ovarian dysfunction by activating the apoptotic ERK and JNK signaling pathways.

Glutathione-triggered formation of molecular hydrogels for 3D cell culture.

The development of three dimensional (3D) scaffolds that are suitable for cell encapsulation and proliferation is highly important for tissue engineering and regenerative medicine. We reported in this paper on several molecular hydrogels formed through glutathione (GSH) reduction, whose mechanical property and zeta potential could be regulated by concentration and structure of gelators in resulting gels, respectively. The hydrogels were characterized by several techniques including rheology, TEM and fluorescence. We found that, in our system, the mechanical property of hydrogels but not the zeta potential of self-assembled structures had big influences on mouse fibroblast 3T3 cells spreading and proliferation. Hydrogels with storage modulus (G') of hundreds of pascals (Pa) were suitable for 3T3 cells spreading and proliferation. We believed that hydrogels reported in this study had big potential for applications in different fields, such as 3D cell culture and tissue engineering.

Effects of sodium fluoride on reproductive function in female rats.

The aim of this study was to investigate the effects of sodium fluoride (NaF) on female reproductive function and examine the morphology of the ovaries and uteri of rats exposed to NaF. Eighty female Sprague-Dawley (SD) rats were divided randomly into four groups of 20: one control group and three NaF treated groups. The three NaF treated groups received 100, 150, and 200 ppm, respectively, of NaF for 6 months via their drinking water, while the control group (GC) received distilled water. The levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T), progesterone (P) and estradiol (E2) were measured using an enzyme-linked immunosorbent assay. Pathomorphological evaluation of the uteri and ovaries was conducted after staining with hematoxylin-eosin and immunohistochemistry. The rate of successful pregnancy in the NaF-treated groups declined in a dose-dependent manner. The concentration of reproductive hormones was significantly lower in the three NaF-treated groups, and the endometrium was damaged. The maturation of follicles was inhibited. In addition, the total number of follicles of all types was significantly lower in the NaF-treated groups. These results suggest that female reproductive function is inhibited by NaF and that exposure to NaF causes ovarian and uterine structural damage. NaF may thus significantly reduce the fertility of female rats.

The toxicity mechanism of sodium fluoride on fertility in female rats.

Recognition of the harmful effects of sodium fluoride (NaF) on human reproduction is increasing, especially as it relates to female reproduction. However, the mechanism by which NaF interferes with female reproduction is unclear. The aims of the present study were to investigate the effects of fluoride exposure on female fertility and to elucidate the mechanisms underlying these effects. Female Sprague-Dawley rats were divided into three groups: one control group and two NaF-treated groups (100 and 200 mg/L in the drinking water for 12 weeks). Several parameters were evaluated, including: (i) fluoride concentrations; (ii) estrogen (E2) and progesterone (P) concentrations; (iii) estrogen receptor alpha protein (ERα); (iv) progesterone receptor (PgR) protein; (v) follicle-stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHR) protein. The results indicated that administration of NaF lead to significant decreases in E2 and P levels in the serum and in the expression of FSHR protein. In addition, fluoride exposure significantly increased Erα and PgR protein expression levels and LHR protein expression. These results suggest that the reproductive hormone reduction and the abnormalities of related receptor proteins expression are important factors underlying the decreased fertility observed in female rats that have been exposed to NaF.

Molecular hydrogelators of peptoid-peptide conjugates with superior stability against enzyme digestion.

We report on molecular hydrogelators based on peptoid-peptide conjugates with good biocompatibility to different cells and superior stability against proteinase K digestion.

Disulfide bond as a cleavable linker for molecular self-assembly and hydrogelation.

Here we reported on the first example of using the disulfide bond as a cleavable linker to control molecular self-assembly and the formation of small molecular (SM) hydrogels.

A hybrid hydrogel for efficient removal of methyl violet from aqueous solutions.

In this study, we reported on the incorporation of a novel supramolecular hydrogel into agarose hydrogel to create a hybrid hydrogel. Both the supramolecular hydrogel and the hybrid hydrogel were characterized by scanning electron microscopy (SEM) and fluorescence microscopy, and their mechanical properties were evaluated by a compress assay. These results showed that the hybrid hydrogel possessed much better mechanical properties and stability than the supramolecular hydrogel itself. The hybrid hydrogel could be applied to efficiently remove methyl violet from an aqueous phase without affecting its appearance under vigorous stirring, while the supramolecular hydrogel changed to a fragile solid after the absorption of a large amount of methyl violet even under the free-standing mode. Such a hybrid hydrogel has the potential for use in the efficient removal of dye molecules from aqueous solutions.

Tuning of the vinyl groups' spacing at surface of modified silica in preparation of high density imprinted layer-coated silica nanoparticles: a dispersive solid-phase extraction materials for chlorpyrifos.

This paper reports the preparation of high density imprinted layer-coated silica nanoparticles toward selective recognition and fast enrichment of chlorpyrifos (CP) from complicated matrices. The molecularly imprinted polymers (MIPs) were successfully coated at the surface of modified silica through using the chemical immovable vinyl groups at the nanoparticles' surface, followed by the graft copolymerization of methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) in the presence of templates CP. It has been demonstrated that the space of end vinyl groups at the surface of silica can be controlled by changing the condition of chemical modification, regulating the thickness of imprinted shells and the density of efficient imprinted sites. After removal of templates by solvent extraction, the recognition sites of CP were created in the polymer coating layer. The CP-imprinted nanoparticles exhibited high recognition selectivity and binding affinity to CP analyte. When the CP-imprinted nanoparticles were used as dispersive solid-phase extraction (dSPE) materials, the high recovery yields of 76.1-93.5% from various spiked samples with only 1microg/mL analyte were achieved by one-step extraction. These results reported herein provide the possibility for the separation and enrichment of CP from complicated matrices by the molecular imprinting modification at the surface of common silica nanoparticles.