Co-impacts of cation type and humic acid on migration of polystyrene microplastics in saturated porous media.

The aging process of microplastics (MPs) could significantly change their physical and chemical characteristics and impact their migration behavior in soil. However, the complex effects of different cations and humic acids (HA) on the migration of aged MPs through saturated media are not clear. In this research, the migration and retention of pristine/aged PSMPs (polystyrene microplastics) under combined effects of cations (Na+, Ca2+) (ionic strength = 10 mM) and HA (0, 5, 15 mg/L) were investigated and analyzed in conjunction with the two-site kinetic retention model and DLVO theory. The findings showed that the aging process accelerated PSMPs migration under all tested conditions. Aged PSMPs were less susceptible to Ca2+ than pristine PSMPs. Under Ca2+ conditions, pristine/aged PSMPs showed higher retention than under Na+ conditions in the absence of HA. Furthermore, under Na+ conditions, the migration of aged PSMPs significantly increased at higher concentrations of HA. However, under Ca2+ conditions, the migration of aged PSMPs decreased significantly at higher concentrations of HA. In higher HA conditions, HA, Ca2+, and PSMPs interact to cause larger aggregations, resulting in the sedimentation of aged PSMPs. The DLVO calculations and two-site kinetic retention models' results showed the detention of PSMPs was irreversible under higher HA conditions (15 mg/L) with Ca2+, and aged PSMPs were more susceptible to clogging. These findings may help to understand the potential risk of migration behavior of PSMPs in the soil-groundwater environment.

[Recent Advance of Stainless Steel Used In Non-active Surgical Implantable Medical Device and Regulatory Perspective].

Stainless steel has been widely used in non-active surgical implantable medical device of cardiovascular, orthopedics, dental and ophthalmology. In this paper, we mainly focused on development of stainless steel, as well as the material-related standard evolution. We further summarized the recent advancement of stainless steel use in surgical implantable medical device. Insight and regulatory perspective has been further demonstrated.

Epirubicin-loaded superparamagnetic iron-oxide nanoparticles for transdermal delivery: cancer therapy by circumventing the skin barrier.

The transdermal administration of chemotherapeutic agents is a persistent challenge for tumor treatments. A model anticancer agent, epirubicin (EPI), is attached to functionalized superparamagnetic iron-oxide nanoparticles (SPION). The covalent modification of the SPION results in EPI-SPION, a potential drug delivery vector that uses magnetism for the targeted transdermal chemotherapy of skin tumors. The spherical EPI-SPION composite exhibits excellent magnetic responsiveness with a saturation magnetization intensity of 77.8 emu g(-1) . They feature specific pH-sensitive drug release, targeting the acidic microenvironment typical in common tumor tissues or endosomes/lysosomes. Cellular uptake studies using human keratinocyte HaCaT cells and melanoma WM266 cells demonstrate that SPION have good biocompatibility. After conjugation with EPI, the nanoparticles can inhibit WM266 cell proliferation; its inhibitory effect on tumor proliferation is determined to be dose-dependent. In vitro transdermal studies demonstrate that the EPI-SPION composites can penetrate deep inside the skin driven by an external magnetic field. The magnetic-field-assisted SPION transdermal vector can circumvent the stratum corneum via follicular pathways. The study indicates the potential of a SPION-based vector for feasible transdermal therapy of skin cancer.

Efficient solution-processed double-layer red OLEDs based on a new europium complex with a carbazole group.

A new europium complex EuL3 (Phen) was used as guest dopant, and a blend of Polyvinylcarbazole and 2-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PVK and PBD) as host matrix. Efficient red organic light-emitting devices (OLEDs) with double-layer structures were manufactured via a solution-processed technique. The guest-doped levels were 1, 3 and 5 wt% relative to the blend mass, respectively. For the 1 wt% doping-level device, the luminous efficiency and luminance were up to 2.96 cd/A and 635.78 cd/m(2) with emissions from both EuL3 (Phen) and from the host; for the 3 wt% doping-level device, the maximum luminous efficiency and luminance were 1.01 cd/A and 370.91 cd/m(2) for the single emission from EuL3 (Phen) only.

Studying the role of common membrane surface functionalities on adsorption and cleaning of organic foulants using QCM-D.

Adsorption of organic foulants on nanofiltration (NF) and reverse osmosis (RO) membrane surfaces strongly affects subsequent fouling behavior by modifying the membrane surface. In this study, impact on organic foulant adsorption of specific chemistries including those in commercial thin-film composite membranes was investigated using self-assembled monolayers with seven different ending chemical functionalities (-CH(3), -O-phenyl, -NH(2), ethylene-glycol, -COOH, -CONH(2), and -OH). Adsorption and cleaning of protein (bovine serum albumin) and polysaccharide (sodium alginate) model foulants in two solution conditions were measured using quartz crystal microbalance with dissipation monitoring, and were found to strongly depend on surface functionality. Alginate adsorption correlated with surface hydrophobicity as measured by water contact angle in air; however, adsorption of BSA on hydrophilic -COOH, -NH(2), and -CONH(2) surfaces was high and dominated by hydrogen bond formation and electrostatic attraction. Adsorption of both BSA and alginate was the fastest on -COOH, and adsorption on -NH(2) and -CONH(2) was difficult to remove by surfactant cleaning. BSA adsorption kinetics was shown to be markedly faster than that of alginate, suggesting its importance in the formation of the conditioning layer. Surface modification to render -OH or ethylene-glycol functionalities are expected to reduce membrane fouling.

[Impact of regenerated silk protein membrane on the cytokine expression of transfected human corneal epithelium cells].

OBJECTIVE: The purpose of this research was to study the influence of the regenerated silk fibroin film (SF) on cytokines expression of transfected human corneal epithelial cells (HCECs) and to investigate the possibility of constructing biomaterial complex using SF, modified by transgenic cells. METHODS: Empirical study.Ad-VEGF(165) was injected into the limbus of a rabbit's cornea to induce cornea neovascularization (CNV). CNV was evaluated by growth areas and VEGF characteristic was evaluated by immunohistochemistry. HCECs was cultivated on silk protein membrane in the cell cultivation plate. Modality of cells, activity of cell proliferation and infection efficiency of Ad-VEGF(165) were monitored to evaluate the biocompatibility of silk fibroin. The angiogenesis-related cytokines in the cell cultivation supernatant was measured using ELISA method such as vascular endothelial growth factor (VEGF), angiogenin 1 (Ang1), epidermal growth factor (EGF) and transforming growth factor-beta (TGF-beta) in the supernatant (Two-way analysis of variance). RESULTS: (1) The area of corneal neovascularization was observed to be (7.60 +/- 1.12) mm(2) at 1 week after Ad-VEGF(165) was injected and it became (12.28 +/- 2.54) mm(2) another three weeks later. Positive expression of VEGF in corneal stromal was observed by immunohistochemistry at 3 d, 1 week and 1 month after injection. (2) There was no difference noticed in amorphous, growth curve and infection efficiency of Ad-VEGF(165) between both cells culture conditions of silk protein membrane and plate cultivation. (3) After transfection, the concentration of VEGF, Ang1, EGF and TGF-beta expressions in the corneal epithelium cell cultivation supernatant with silk protein membrane as carriers was (721.67 +/- 66.97) ng/L, (1042.67 +/- 315.81) ng/L, (2421.00 +/- 0.00) ng/L, and (313.33 +/- 34.06) ng/L respectively; and the concentration of each of the aforementioned expression was (721.67 +/- 66.97) ng/L, (860.33 +/- 315.81) ng/L, (1960.33 +/- 797.90) ng/L, and (278.00 +/- 53.11) ng/L without using silk protein membrane as carriers. The increase of VEGF (F = 168.16, P < 0.0001), EGF (F = 52.76, P < 0.0001), Ang1 (F = 12.47, P = 0.001), and TGF-beta (F = 0.008, P = 0.932) in the Ad-VEGF(165) group was considered statistically significant; however, there was no evident change in the concentration of VEGF (F = 0.071, P = 0.793), EGF (F = 0.563, P = 0.465), Ang1 (F = 0.14, P = 0.714), and TGF-beta (F = 0.008, P = 0.932)expressions in the corneal epithelium cell cultivation supernatant both with or without using silk protein membrane as carriers. CONCLUSION: Same as cell HCECs culturing in the cultivation plate, through SF application, VEGF(165) destination gene could be high-level expressed in the supernatant having which the HCECs is cultured on SF, and in addition, the angiogenesis-related cytokines content of Ang1, EGF, and TGF-beta autocrine in the HCECS cultivation supernatant could be high-level expressed as well.

Redox-responsive chitosan oligosaccharide-SS-Octadecylamine polymeric carrier for efficient anti-Hepatitis B Virus gene therapy.

DrzBC and DrzBS (10-23 DNAzyme) could block the expression of HBV e- and s- gene respectively. But the application of 10-23 DNAzyme was limited owing to the lack of appropriate delivery vehicles. Chitosan oligosaccharide-SS-Octadecylamine (CSSO), a redox-responsive nano-sized polymeric carrier, could self-aggregate and bind with DNA by electrostatic interaction at proper mass ratio. Compared with the traditional commercial carrier Lipo2000, CSSO exhibited lower cytotoxicity, efficient cellular uptake by targeting cells, and rapidly DNA released in cytoplasm after escaping from endosomes. Including the same DNA concentration, Lipo2000/(DrzBC or DrzBS) showed maximum inhibitory rate on HBeAg (47.29 ±â€¯1.86%) and HBsAg (33.58 ±â€¯0.72%) secretion after 48 h incubation, and then both decreased. In contrast, HBeAg secretion inhibition by CSSO/DrzBC and HBsAg secretion inhibition by CSSO/DrzBS were up to 73.86 ±â€¯1.77% and 67.80 ±â€¯2.51% at 48 h, and further increased to 83.83 ±â€¯2.34% and 76.79 ±â€¯2.18% at 72 h, respectively. CSSO is a promising redox-responsive polymeric carrier for efficient anti-Hepatitis B Virus gene therapy.

Cellular uptake of solid lipid nanoparticles and cytotoxicity of encapsulated paclitaxel in A549 cancer cells.

The aim of this study was to investigate the cellular uptake of solid lipid nanoparticles (SLN) and cytotoxicity of its paclitaxel delivery system. The conjugate of octadecylamine-fluorescein isothiocyanate (ODA-FITC) was synthesized, and used as a marker to prepare fluorescent SLN. The cellular uptakes of fluorescent SLN with different lipid material were evaluated by fluorescence microscopy and the measurement of fluorescence intensity. The order of cellular uptake ability was glycerol tristearate SLN>monostearin SLN>stearic acid SLN>Compritol 888 ATO SLN (ATO888 SLN). The cellular cytotoxicities of paclitaxel were highly enhanced by the encapsulation of lipid matrix. Due to the lower drug entrapment efficiency of glycerol tristearate SLN, monostearin SLN was considered as the best lipid material to improve the cytotoxicity of drug. The polyethylene glycol monostearate (PEG-SA) and the synthesized conjugate of folic acid-stearic acid (FA-SA) were further introduced into monostearin SLN, respectively. The PEG and folate modified SLN could enhance the cellular uptake of SLN and the cellular cytotoxicity of drug by the membrane disturb ability of PEG chains on the SLN surface and the improved endocytosis mediated by folate receptor.

Recurrent Cerebral Infarctions in Primary Sjögren Syndrome: A Case Report and Literature Review.

Recurrent cerebral infarctions are extremely rare in patients with primary Sjögren syndrome. We report a 66-year-old woman who was admitted to our hospital due to acute cerebral infarction with exacerbation of dysphagia and right-sided hemiplegia as the main symptoms. In the past 3 months, she had developed cerebral infarction twice, even though she had no risk factors for atherosclerosis. She was eventually diagnosed with primary Sjögren syndrome based on a long history of dryness of the eyes and mouth, positive anti-Ro(SSA) antibodies, and the findings of a labial salivary gland biopsy. The response to pulse methylprednisolone therapy after recurrent cerebral infarctions was poor. Thus we consider primary Sjögren syndrome patients with central nervous system involvement should be treated as soon as possible.

Hyaluronic acid reagent functional chitosan-PEI conjugate with AQP2-siRNA suppressed endometriotic lesion formation.

To identify a new drug candidate for treating endometriosis which has fewer side effects, a new polymeric nanoparticle gene delivery system consisting of polyethylenimine-grafted chitosan oligosaccharide (CSO-PEI) with hyaluronic acid (HA) and small interfering RNA (siRNA) was designed. There was no obvious difference in sizes observed between (CSO-PEI/siRNA)HA and CSO-PEI/siRNA, but the fluorescence accumulation in the endometriotic lesion was more significant for (CSO-PEI/siRNA)HA compared with CSO-PEI/siRNA due to the specific binding of HA to CD44. In addition, the (CSO-PEI/siRNA)HA nanoparticle gene therapy significantly decreased the endometriotic lesion sizes with atrophy and degeneration of the ectopic endometrium. The epithelial cells of ectopic endometrium from rat models of endometriosis showed a significantly lower CD44 expression than control after treatment with (CSO-PEI/siRNA)HA. Furthermore, observation under an electron microscope showed no obvious toxic effect on the reproductive organs. Therefore, (CSO-PEI/siRNA)HA gene delivery system can be used as an effective method for the treatment of endometriosis.

Cytocompatibility of regenerated silk fibroin film: a medical biomaterial applicable to wound healing.

OBJECTIVE: To explore the feasibility of using regenerated silk fibroin membrane to construct artificial skin substitutes for wound healing, it is necessary to evaluate its cytocompatibility. METHODS: The effects of regenerated silk fibroin film on cytotoxicity, adhesion, cell cycle, and apoptosis of L929 cells, growth and vascular endothelial growth factor (VEGF) expression of ECV304 cells, and VEGF, angiopoietin-1 (Ang-1), platelet-derived growth factor (PDGF) and fibroblast growth factor 2 (FGF2) expression of WI-38 cells were assessed by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) assay, viable cell counting, flow cytometry (FCM), and enzyme-linked immunosorbant assay (ELISA). RESULTS: We showed that the regenerated silk fibroin film was not cytotoxic to L929 cells and had no adverse influence on their adhesion, cell cycle or apoptosis; it had no adverse influence on the growth and VEGF secretion of ECV304 cells and no effect on the secretion of VEGF, Ang-1, PDGF and FGF2 by WI-38 cells. CONCLUSION: The regenerated silk fibroin film should be an excellent biomaterial with good cytocompatibility, providing a framework for reparation after trauma in clinical applications.