Facile Fabrication of Multifunctional Hydrogel Nanoweb Coating Using Carboxymethyl Chitosan-Based Short Nanofibers for Blood-Contacting Medical Devices.

Blood-contacting medical devices (BCDs) require antithrombotic, antibacterial, and low-friction surfaces. Incorporating a nanostructured surface with the functional hydrogel onto BCD surfaces can enhance the performances; however, their fabrication remains challenging. Here, we introduce a straightforward method to fabricate a multifunctional hydrogel-based nanostructure on BCD surfaces using O-carboxymethyl chitosan-based short nanofibers (CMC-SNFs). CMC-SNFs, fabricated via electrospinning and cutting processes, are easily sprayed and entangled onto the BCD surface. The deposited CMC-SNFs form a robust nanoweb layer via fusion at the contact area of the nanofiber interfaces. The superhydrophilic CMC-SNF nanoweb surface creates a water-bound layer that effectively prevents the nonspecific adhesion of bacteria and blood cells, thereby enhancing both antimicrobial and antithrombotic performances. Furthermore, the CMC-SNF nanoweb exhibits excellent lubricity and durability on the bovine aorta. The demonstration results of the CMC-SNF coating on catheters and sheaths provide evidence of its capability to apply multifunctional surfaces simply for diverse BCDs.

Security Comparison of Various Surgical Knots Using Nylon Suture.

OBJECTIVE: To evaluate the strengths of various surgical knot techniques, including square knot, surgeon's knot, granny knot, and random knot with the same three throws. METHODS: The authors tested each of the four knot techniques using four different gauges of nylon (polyamide [Ethicon]): 4-0, 5-0, 6-0, and 7-0. Each knot type was tested 20 times per nylon gauge, for a total of 320 knots tested. The authors used a static pull machine to measure elongation at yield and maximal force to break. RESULTS: A comparison of elongation at yield revealed that the surgeon's knot was superior to the square knot, granny knot, and random knots across all gauges of nylons. Further, a comparison of maximal force to break revealed that the surgeon's knot was superior to the square knot, granny knot, and random knots when using 4-0, 5-0, and 6-0 nylon but not when using 7-0 nylon. CONCLUSIONS: The surgeon's knot was the strongest, and random knot was the weakest when the authors used nylon 4-0, 5-0, and 6-0. While handling fine suture materials such as 7-0 nylon, knot failure appears to be unrelated to the knot technique used. This study provides not only fundamental guidance for tying surgical knots using nylon, but also a rational basis for an adequately strong knot choice in various fields of surgery.

Functional expression of polyethylene terephthalate-degrading enzyme (PETase) in green microalgae.

BACKGROUND: For decades, plastic has been a valuable global product due to its convenience and low price. For example, polyethylene terephthalate (PET) was one of the most popular materials for disposable bottles due to its beneficial properties, namely impact resistance, high clarity, and light weight. Increasing demand of plastic resulted in indiscriminate disposal by consumers, causing severe accumulation of plastic wastes. Because of this, scientists have made great efforts to find a way to biologically treat plastic wastes. As a result, a novel plastic degradation enzyme, PETase, which can hydrolyze PET, was discovered in Ideonella sakaiensis 201-F6 in 2016. RESULTS: A green algae, Chlamydomonas reinhardtii, which produces PETase, was developed for this study. Two representative strains (C. reinhardtii CC-124 and CC-503) were examined, and we found that CC-124 could express PETase well. To verify the catalytic activity of PETase produced by C. reinhardtii, cell lysate of the transformant and PET samples were co-incubated at 30 °C for up to 4 weeks. After incubation, terephthalic acid (TPA), i.e. the fully-degraded form of PET, was detected by high performance liquid chromatography analysis. Additionally, morphological changes, such as holes and dents on the surface of PET film, were observed using scanning electron microscopy. CONCLUSIONS: A PET hydrolyzing enzyme, PETase, was successfully expressed in C. reinhardtii, and its catalytic activity was demonstrated. To the best of our knowledge, this is the first case of PETase expression in green algae.

Amplified intracellular Ca2+ for synergistic anti-tumor therapy of microwave ablation and chemotherapy.

BACKGROUND: Developing new strategies to reduce the output power of microwave (MW) ablation while keeping anti-tumor effect are highly desirable for the simultaneous achievement of effective tumor killing and avoidance of complications. We find that mild MW irradiation can significantly increase intracellular Ca2+ concentration in the presence of doxorubicin hydrochloride (DOX) and thus induce massive tumor cell apoptosis. Herein, we designed a synergistic nanoplatform that not only amplifies the intracellular Ca2+ concentration and induce cell death under mild MW irradiation but also avoids the side effect of thermal ablation and chemotherapy. RESULTS: The as-made NaCl-DOX@PLGA nanoplatform selectively elevates the temperature of tumor tissue distributed with nanoparticles under low-output MW, which further prompts the release of DOX from the PLGA nanoparticles and tumor cellular uptake of DOX. More importantly, its synergistic effect not only combines thermal ablation and chemotherapy, but also obviously increases the intracellular Ca2+ concentration. Changes of Ca2+ broke the homeostasis of tumor cells, decreased the mitochondrial inner membrane potential and finally induced the cascade of apoptosis under nonlethal temperature. As such, the NaCl-DOX@PLGA efficiently suppressed the tumor cell progression in vivo and in vitro under mild MW irradiation for the triple synergic effect. CONCLUSIONS: This work provides a biocompatible and biodegradable nanoplatform with triple functions to realize the effective tumor killing in unlethal temperature. Those findings provide reliable solution to solve the bottleneck problem bothering clinics about the balance of thermal efficiency and normal tissue protection.

Bilirubin Nanoparticle-Assisted Delivery of a Small Molecule-Drug Conjugate for Targeted Cancer Therapy.

Despite growing interest in targeted cancer therapy with small molecule drug conjugates (SMDCs), the short half-life of these conjugates in blood associated with their small size has limited their efficacy in cancer therapy. In this report, we propose a new approach for improving the antitumor efficacy of SMDCs based on nanoparticle-assisted delivery. Ideally, a nanoparticle-based delivery vehicle would prolong the half-life of an SMDC in blood and then release it in response to stimuli in the tumor microenvironment (TME). In this study, PEGylated bilirubin-based nanoparticles (BRNPs) were chosen as an appropriate delivery carrier because of their ability to release drugs in response to TME-associated reactive oxygen species (ROS) through rapid particle disruption. As a model SMDC, ACUPA-SN38 was synthesized by linking the prostate-specific membrane antigen (PSMA)-targeting ligand, ACUPA, to the chemotherapeutic agent, SN38. ACUPA-SN38 was loaded into BRNPs using a film-formation and rehydration method. The resulting ACUPA-SN38@BRNPs exhibited ROS-mediated particle disruption and rapid release of the SMDC, resulting in greater cytotoxicity toward PSMA-overexpressing prostate cancer cells (LNCaP) than toward ROS-unresponsive ACUPA-SN38@Liposomes. In a pharmacokinetic study, the circulation time of ACUPA-SN38@BRNPs in blood was prolonged by approximately 2-fold compared with that of the SMDC-based micellar nanoparticles. Finally, ACUPA-SN38@BRNPs showed greater antitumor efficacy in a PSMA-overexpressing human prostate xenograft tumor model than SN38@BRNPs or the SMDC alone. Collectively, these findings suggest that BRNPs are a viable delivery carrier option for various cancer-targeting SMDCs that suffer from short circulation half-life and limited therapeutic efficacy.

The negative feedback regulation of microRNA-146a in human periodontal ligament cells after Porphyromonas gingivalis lipopolysaccharide stimulation.

OBJECTIVE: Toll-like receptors (TLRs) pathway has been demonstrated to play an important role in periodontitis. However, the regulatory mechanism of microRNAs (miRNAs) on TLRs pathway is still unclear. Hence, this study is to explore the function of miRNA-146a in inflammatory reaction induced by Porphyromonas gingivalis lipopolysaccharide (LPS) in human periodontal ligament cells (hPDLCs). METHODS: Cells were treated with 1 or 10 µg/ml P. gingivalis LPS. The expression of TLR2, TLR4 and miRNA-146a were measured by real-time polymerase chain reaction (PCR). Enzyme-linked immunosorbent assay (ELISA) was applied to detect nuclear factor (NF)-κ B p65 nuclear activity, interleukin-1ß (IL-1ß), IL-6, IL-8 and tumor necrosis factor-α (TNF-α). To examine the underlying mechanisms, cells were exposed to anti-TLR2/4 mAb or miRNA-146a inhibitor/mimic and evaluated by real-time PCR and ELISA. RESULTS: 10 µg/ml P. gingivalis LPS increased the expressions of TLR2 (3.79 ± 0.31), TLR4 (2.21 ± 0.31), and miRNA-146a (4.91 ± 0.87), NF-κ B p65 nuclear activity (6.51 ± 0.77 fold) (p < 0.05). 1 µg/ml P. gingivalis LPS induced TLR2 (3.05 ± 0.23), miRNA-146a (3.66 ± 0.83) and NF-κ B p65 nuclear activity (4.06 ± 0.78 fold) (p < 0.05), except TLR4 (1.11 ± 0.30, p > 0.05). Also, cytokines production increased (p < 0.05). The up-regulation of miRNA-146a could be blocked by anti-TLR2/4 mAb (p < 0.05). After the blockage of miRNA-146a, TLR2, TLR4, NF-κ B p65 nuclear activity and proinflammatory cytokines increased. However, after application of miRNA-146a mimic, the levels of these indexes decreased obviously (p < 0.05). CONCLUSION: MiRNA-146a functions as a negative feedback regulator via down-regulating proinflammatory cytokine secretion and blocking TLRs signaling pathway in hPDLCs after P. gingivalis LPS stimulation.

Horticultural therapy: a pilot study on modulating cortisol levels and indices of substance craving, posttraumatic stress disorder, depression, and quality of life in veterans.

CONTEXT: Horticultural therapy (HT) is a subgroup of occupational therapy (OT). Both HT and OT have been successful as adjunctive treatment modalities in substance abuse treatment. Studies have indicated that gardening promotes neuroendocrine and affective restoration from stress. OBJECTIVES: The study intended to assess the effect of HT versus nonhorticultural OT on cortisol levels, depression, symptoms of posttraumatic stress disorder (PTSD), alcohol cravings, and quality of life. METHODS: The research team designed a randomized pilot study. SETTING: The study was open for participation from July 2012-October 2012. It took place during multiple occurrences of a 28-d treatment programs for substance use disorder at a Veterans Affairs medical center. Participants • Participants were 49 veterans, averaging 46.4 y old (SD = 11.9); the dropout rate was 37%. INTERVENTION: Participants were randomly assigned to the HT or the OT group. They attended supervised HT and OT groups 5 h/d for 3 wk. Outcome Measures • Pre- and posttreatment, participants completed the Quality of Life Enjoyment and Satisfaction Questionnaire-Short Form (Q-LES-Q-SF), the Alcohol Craving Questionnaire (ACQ-NOW), the Posttraumatic Stress Disorder Checklist Civilian Version (PCLC), and the Center for Epidemiologic Studies Depression Scale (CES-D). Salivary cortisol samples were taken at wk 1, 2, and 3. RESULTS: A repeated measures analysis of variance (ANOVA) (F2,20 = 0.878) revealed that the HT performed was associated with a 12% reduction in salivary cortisol levels from wk 1 to wk 3, but the difference was not statistically significant (P = .43). Separate 1-way analyses of covariance (ANCOVAs) revealed no statistically significant differences in the self-administered tests, although both the Q-LES-Q-SF and CES-D showed a trend toward improving quality of life and depressive symptoms in the HT group compared with the OT group. Additional analysis of the nonbiologic tests suggests that most participants in the HT and OT had some benefit from the programmed activities. CONCLUSIONS: The trends suggest that HT may modulate stress in veterans, as evidenced by decreased cortisol levels and depressive symptoms, and may improve quality of life more than the programs in which the OT group participated. Further investigation with larger samples, including a nontreatment control group, is needed to determine whether the observed trends are treatment effects or due to abstinence.

Local co-delivery of pancreatic islets and liposomal clodronate using injectable hydrogel to prevent acute immune reactions in a type 1 diabetes.

PURPOSE: The purpose of this study was to investigate the effect of locally delivered pancreatic islet with liposomal clodronate (Clodrosome®) as an immunoprotection agent for the treatment of type 1 diabetes. METHOD: The bio-distribution of liposomal clodronate in matrigel was checked by imaging analyzer. To verify the therapeutic efficacy of locally delivered islet with liposomal clodronate using injectable hydrogel, four groups of islet transplanted mice (n = 6 in each group) were prepared: 1) the islet group, 2) the islet-Clodrosome group, 3) the islet-Matrigel group, and 4) the islet-Matrigel-Clodrosome group. Immune cell migration and activation, and pro-inflammatory cytokine secretion was evaluated by immunohistochemistry staining and ELISA assay. RESULTS: Cy5.5 labeled liposomes remained in the matrigel for over 7 days. The median survival time of transplanted islets (Islet-Matrigel-Clodrosome group) was significantly increased (>60 days), compared to other groups. Locally delivered liposomal clodronate in matrigel effectively inhibited the activation of macrophages, immune cell migration and activation, and pro-inflammatory cytokine secretion from macrophages. CONCLUSIONS: Locally co-delivered pancreatic islets and liposomal clodronate using injectable hydrogel effectively cured type 1 diabetes. Especially, the inhibition of macrophage attack in the early stage after local delivery of islets was very important for the successful long-term survival of delivered islets.

Precisely targeted drug delivery by mesenchymal stem cells-based biomimetic liposomes to cerebral ischemia-reperfusion injured hemisphere.

The precise and targeted delivery of therapeutic agents to the lesion sites remains a major challenge in treating brain diseases represented by ischemic stroke. Herein, we modified liposomes with mesenchymal stem cells (MSC) membrane to construct biomimetic liposomes, termed MSCsome. MSCsome (115.99 ± 4.03 nm) exhibited concentrated accumulation in the cerebral infarcted hemisphere of mice with cerebral ischemia-reperfusion injury, while showing uniform distribution in the two cerebral hemispheres of normal mice. Moreover, MSCsome exhibited high colocalization with damaged nerve cells in the infarcted hemisphere, highlighting its advantageous precise targeting capabilities over liposomes at both the tissue and cellular levels. Leveraging its superior targeting properties, MSCsome effectively delivered Dl-3-n-butylphthalide (NBP) to the injured hemisphere, making a single-dose (15 mg/kg) intravenous injection of NBP-encapsulated MSCsome facilitate the recovery of motor functions in model mice by improving the damaged microenvironment and suppressing neuroinflammation. This study underscores that the modification of the MSC membrane notably enhances the capacity of liposomes for precisely targeting the injured hemisphere, which is particularly crucial in treating cerebral ischemia-reperfusion injury.

D-galacto-D-mannan-mediated Dectin-2 activation orchestrates potent cellular and humoral immunity as a viral vaccine adjuvant.

Introduction: Conventional foot-and-mouth disease (FMD) vaccines have been developed to enhance their effectiveness; however, several drawbacks remain, such as slow induction of antibody titers, short-lived immune response, and local side effects at the vaccination site. Therefore, we created a novel FMD vaccine that simultaneously induces cellular and humoral immune responses using the Dectin-2 agonist, D-galacto-D-mannan, as an adjuvant. Methods: We evaluated the innate and adaptive (cellular and humoral) immune responses elicited by the novel FMD vaccine and elucidated the signaling pathway involved both in vitro and in vivo using mice and pigs, as well as immune cells derived from these animals. Results: D-galacto-D-mannan elicited early, mid-, and long-term immunity via simultaneous induction of cellular and humoral immune responses by promoting the expression of immunoregulatory molecules. D-galacto-D-mannan also enhanced the immune response and coordinated vaccine-mediated immune response by suppressing genes associated with excessive inflammatory responses, such as nuclear factor kappa B, via Sirtuin 1 expression. Conclusion: Our findings elucidated the immunological mechanisms induced by D-galacto-D-mannan, suggesting a background for the robust cellular and humoral immune responses induced by FMD vaccines containing D-galacto-D-mannan. Our study will help to facilitate the improvement of conventional FMD vaccines and the design of next-generation FMD vaccines.

Effects of surface camouflaged islet transplantation on pathophysiological progression in a db/db type 2 diabetic mouse model.

To investigate the inhibition effects of pancreatic islet transplantation on the progression of obese type 2 diabetes, we analyzed the effects of surface camouflaged islet transplantation on delaying the disease progression in a db/db diabetic mouse model. Surface camouflaged islets using 6-arm-PEG-catechol were transplanted in db/db diabetic mice. The fat accumulation and toxicity in the liver, the expansion of islets in the pancreas, and the size change of abdominal adipocyte were analyzed. In addition, the blood glucose control, insulin levels and immunohistochemical staining of recovered tissues were analyzed after transplantation. Then co-administration of anti-CD154 monoclonal antibody and Tacrolimus (IT group) deterred the pathophysiological progression of obese type 2 diabetes. At day 3 of transplantation, the serum insulin concentration of IT group was increased compared to the db/db diabetic mice group. The immunohistochemical studies demonstrated that the mass of 6-arm-PEG-catechol grafted islet was preserved in the transplantation site for 14 days. Surface modification using 6-arm-PEG-catechol effectively inhibited the immune cell infiltration and activation of host immune cells when immunosuppressive drug was given to the db/db type 2 diabetes mice. Therefore, 6-arm-PEG-catechol grafted islets effectively restored the insulin secretion in islet recipients and prevented the disease progression in type 2 diabetes.

Magnetic separation of encapsulated islet cells labeled with superparamagnetic iron oxide nano particles.

Islet cell transplantation is a promising option for the restoration of normal glucose homeostasis in patients with type 1 diabetes. Because graft volume is a crucial issue in islet transplantations for patients with diabetes, we evaluated a new method for increasing functional tissue yield in xenogeneic grafts of encapsulated islets. Islets were labeled with three different superparamagnetic iron oxide nano particles (SPIONs; dextran-coated SPION, siloxane-coated SPION, and heparin-coated SPION). Magnetic separation was performed to separate encapsulated islets from the empty capsules, and cell viability and function were tested. Islets labeled with 1000 µg Fe/ml dextran-coated SPIONs experienced a 69.9% reduction in graft volume, with a 33.2% loss of islet-containing capsules. Islets labeled with 100 µg Fe/ml heparin-coated SPIONs showed a 46.4% reduction in graft volume, with a 4.5% loss of capsules containing islets. No purification could be achieved using siloxane-coated SPIONs due to its toxicity to the primary islets. SPION labeling of islets is useful for transplant purification during islet separation as well as in vivo imaging after transplantation. Furthermore, purification of encapsulated islets can also reduce the volume of the encapsulated islets without impairing their function by removing empty capsules.

Electrical and mechanical properties as a processing condition in polyvinylchloride multi walled carbon nanotube composites.

We investigated the electrical conductivity (sigma) and mechanical property of polyvinylchloride/carbon nanotube composites as a function of the CNT content and processing time during a solid-state process of high speed vibration mixing (HSVM) and high energy ball milling (HEBM). Both processes were suggested to avoid high temperatures, solvents, chemical modification of carbon nanotubes. In this study, the percolation threshold (phi(c)) for electrical conduction is about 1 wt% CNT with a sigma value of 0.21 S/m, and the electrical conductivity is higher value than that reported by other researchers from melt mixing process or obtained from the other solid-state processes. We found that the dispersion of CNTs and morphology change from CNT breaking are closely related to sigma. Especially, a large morphology change in the CNTs was occurred at the specific processing time, and a significant decrease in the electrical conductivity of polyvinylchloride/carbon nanotube composite occurred in this condition. A meaningful increase of electrical properties and mechanical property is observed in the sample with about 1-2 wt% CNT contents sintered at 200 degrees C after the milling for 20 min by HEBM process. Our study indicates the proper process condition required to improve sigma of PVC/CNT composites.

Fabrication of flocculation-resistant pH/ionic strength/temperature multiresponsive hollow microspheres and their controlled release.

pH/ionic strength/temperature multiresponsive hollow microspheres were successfully prepared by the Ce(IV) initiated grafting polymerization of N-isopropylacrylamide (NIPAm) onto the multilayered polyelectrolyte shells encapsulating the polystyrene sulfonate (PSS) microsphere templates fabricated by the layer-by-layer assembly of chitosan (CS) and alginate (SAL), after etching the templates by dialysis. The hollow structure of the obtained multiresponsive hollow microspheres was characterized by transmission electron microscopy (TEM), which indicated that the inner diameter of the hollow microspheres was about 200 nm. The environmental responsive properties of the multiresponsive hollow microspheres were characterized with dynamic light scattering (DLS) in an aqueous system. The introduction of poly(N-isopropylacrylamide) (PNIPAm) brushes onto the pH/ionic strength dual-responsive hollow microspheres achieved temperature-responsive characteristics. It also could prevent flocculation among the obtained multiresponsive hollow microspheres in a solution with higher salt concentration. Their controlled release of drug molecules (a model hydrophobic drug, dipyridamole (DIP)) was also investigated.

Amino acid-mediated negatively charged surface improve antifouling and tribological characteristics for medical applications.

To prevent infections associated with biomedical catheters, various antimicrobial coatings have been investigated. However, those materials do not provide consistent antibacterial effects or biocompatibility, generally, due to degradation of the coating materials, in vivo. Additionally, biomedical catheters must have low surface friction to reduce tribological damage. In this study, we developed an antifouling surface composed of biocompatible amino acids (leucine, taurine, and aspartic acid) on polyimide, via modification using a series of facile immersion steps with waterborne reactions. The naturally derived amino acid could be formed highly biostable amide bonds on the polyimide surface like peptides. The amino acid-modified surface formed a water layer with antifouling performance through the hydrophilic properties of amino acids. Amino acid-mediated modification reduced adhesion up to 84.45% and 94.81% against Escherichia coli and Staphylococcus epidermidis, respectively, and exhibited an excellent prevention to adhesion against the proteins, albumin and fibrinogen. Evaluation of the surface friction of the catheter revealed a dramatic reduction in the tribological force after amino acid modification on polyimide that of 0.81 N to aspartic acid of 0.44 N. These results clearly demonstrate a reduced occurrence of infections, thrombi and tribological damage following the relatively facile surface modification of catheters. The proposed modification method can be used in a continuous manufacturing process via using the same time of modification steps for the easy producing the product. Moreover, the method uses biocompatible naturally derived materials and can be applied to medical equipment that requires biocompatibility and biofunctionality with polyimide surfaces.

Bio-inspired strategy for on-surface synthesis of silver nanoparticles for metal/organic hybrid nanomaterials and LDI-MS substrates.

A strategy for the on-surface synthesis of silver nanoparticles (AgNPs) on a variety of two- to three-dimensional material surfaces, utilizing polydopamine, an emerging surface modifying agent, is reported in this paper. This material-independent platform for AgNP synthesis is useful for fabricating organic/inorganic hybrid nanomaterials and for preparing substrates for laser desorption-ionization time-of-flight mass spectrometry (LDI-ToF MS).

Enhancing the antibacterial activity of biomimetic HA coatings by incorporation of norvancomycin.

BACKGROUND: Bacterial infections associated with the use of biomaterials remain a great challenge for orthopedic surgery. The main purpose of the work discussed in this paper was to improve the antibacterial activity of a biomimetic calcium phosphate (CP) coating widely used in orthopedic biomaterials by incorporation of norvancomycin in the biomimetic process. METHODS: CP coating and CP coating containing norvancomycin were produced on a titanium alloy (Ti6Al4V) surface by a biomimetic process. The morphology, surface crystal structure, and concentrations of elements in the coatings were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDX), respectively. The amount of norvancomycin and its release were investigated by UV-visible spectroscopy. MTT was used to investigate cell behavior. The morphology of adhered bacteria was observed by SEM. Antibacterial activity was expressed as inhibition zone by using Staphylococcus aureus (ATCC 25923) as model bacteria. RESULTS: Results from SEM, EDX, and XRD revealed formation of a hydroxyapatite (HA) coating. The amount of antibiotic in the CP coating increased with increasing concentration of norvancomycin in the coating solution, followed by a plateau when the concentration of norvancomycin in the coating solution reached 600 mg/l. Approximately 2.16 µg norvancomycin per mg coating was co-precipitated with the CP layer onto titanium alloy discs when 600 mg/l norvancomycin coating solution was applied. The norvancomycin had a fast release profile followed by slow release. The MTT test of osteoblast cell cultures suggested that coatings containing norvancomycin did not cause any cytotoxicity compared with the CP coating and control titanium plate. The antibacterial activity test showed that the norvancomycin released from the coatings inhibited the growth of Staphylococcus aureus; more bacteria were found on the CP coating than on the norvancomycin-loaded coating. CONCLUSIONS: A norvancomycin-loaded HA-like coating was successfully obtained on titanium surfaces. The norvancomycin incorporated had no negative effects on osteoblast cell behavior. The released norvancomycin results in excellent antibacterial activity of Ca-P coatings. Therefore, incorporation of norvancomycin can enhance antibacterial activity and the norvancomycin-loaded CP coating can be used to inhibit post-surgical infections in orthopaedics.

808 nm NIR Laser-Excited Upconversion Nanoplatform for Combinatory Photodynamic and Chemotherapy with Deep Penetration and Acid Bursting Release Performance.

Combinatory photodynamic and chemotherapy have demonstrated superior performance in cancer ablation over singular therapeutics. However, photodynamic therapy (PDT) often exhibits suboptimal efficacy for deep-seated tumors, owing to the limited penetration depth of illumination light, while chemotherapy is generally accompanied by severe side effects. Therefore, it is imperative to develop a functional nanoplatform for combinatory PDT and chemotherapy, which could, for PDT, achieve enhanced light penetration and, for chemotherapy, realize reduced therapeutic threshold dosage and a controllable drug release profile (e.g., minimized release in blood circulation but bursting release in the tumor microenvironment). Herein, we demonstrate a therapeutic nanoplatform composed of poly(acrylic acid) (PAA)-modified silica-coated Nd3+-doped upconversion nanoparticles decorated with methylene blue (MB) and doxorubicin (DOX) in silica and a PAA layer, respectively. Notably, 808 nm light is used to excite upconversion nanoparticles and further trigger the photosensitization behavior of MB in PDT, while the quick acid response of the PAA layer in the tumor acid environment introduces DOX bursting for optimized chemotherapy with significantly decreased therapeutic threshold dosage and minimized side effects. Importantly, the anticancer efficiency of the nanoplatform in vitro and in vivo shows an IC50 and a tumor inhibition rate of 12.55 µg mL-1 and 89.81%, respectively. This study provides a strategy for combinatory cancer therapy.

Chemical and geometrical criteria for the release of elastomeric 1D nanoarrays from porous nanotemplates.

Releasing 1D nanoarrays from nanotemplates is a significant challenge for the integration of mechanically soft materials in a variety of newly emerging technological areas. To fabricate nanoarrays without defects, the combined effects of the surface energy and the geometric features of the nanotemplate should be considered. A previously reported approach based on the correlation between the adhesion energy and the real contact area was not satisfactory to describe the rupture conditions of the nanofibers while they were being peeled off from the porous template. Here we demonstrate that the aspect ratio rather than the contact area of the nanoporous template is the key factor determining the upper limit of the pore length of the nanotemplate with respect to the rupture of the nanoarray during separation. We propose that the value of alpha(c)*, which is calculated with a simple expression in which the adhesion energy is multiplied by the aspect ratio, can be used as an excellent criterion for the fabrication of 1D nanoarrays without defects with a simple peel-off processes. Our approach opens up new applications for unconventional lithographic techniques, such as soft lithography, imprint lithography, and others.

The legacy of trace metal deposition from historical anthropogenic river management: A regional driver of offshore sedimentary microbial diversity.

River management, both modern and historical, have dramatically modified offshore environments. While numerous studies have described the modern impacts, very few have evaluated the legacies remaining from hundreds of years ago. Herein, we show trace metal enrichment in the surface sediment of the abandoned Yellow River Delta, hypothesized to be associated with ancient river management. Essentially, anthropogenic modification caused the river to shift, creating a 12.4×103 km2 area with elevated trace metals; characterized by clear metal deposition gradients. Geographical factors related to the ancient river mouth had the most significant influences on Zn (explained by distance to the river mouth, DTM) and Cd (DTM and sediment salinity), while the sediment absorptive capacity was associated with the reallocation of Cu (clay, silt, and iron), Ni (clay and iron), and Pb (silt and iron). Trace metal legacies showed stronger influences on prokaryotic diversity than on micro-eukaryotic diversity, with the former best described by changes in rare, rather than dominant families and classes, and explainable by an "overlapping micro-niche" model. The ancient river's legacies provide evidence of longer-term human disturbance over hundreds of years; as its impacts on associated benthic microbiomes have led to lessons for modern-day waterway management of benthic ecosystems.