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The development of wound-dressing materials has attracted significant research interests in recent years. With the advancement of nanofabrication, the application of nanoparticles (NPs) in drug delivery systems has become feasible. However, most existing work focuses on incorporation of metal, metal/semi-metal oxide, or organic particles into nanofiber scaffolds. There has been a lack of work on the incorporation of drug-encapsulated polymeric particles into nanofiber scaffolds. In this study, gentamicin-encapsulated poly-(lactic-co-glycolic acid) (PLGA) NPs were synthesized via a double emulsion solvent evaporation method. Electrospinning was used to incorporate gentamicin-encapsulated PLGA NPs into nanofiber scaffolds. Atomic force microscopy (AFM), dynamic light scattering, scanning electron microscopy (SEM), ultraviolet–visible spectroscopy (UV–vis), and an agar diffusion method were utilized to characterize the morphologies, release profiles, and antibacterial activities of various gentamicin-loaded PLGA NP-incorporated nanofiber scaffolds. The results indicated that the PLGA NPs had a spherical morphology with an average diameter of 130 nm. Purification of PLGA NPs was essential to eliminate the residual poly-(vinyl alcohol) (PVA) and to prevent particle agglomeration. The purified PLGA NPs were uniformly and individually incorporated into the polyurethane (PU)/ poly-(ethenyl oxide) (PEO) or PEO-only nanofiber scaffolds but nearly none into the PU-only fiber scaffolds. PEO served as a continuous phase in the PU/PEO mixture, which significantly improved the compatibility of PLGA NPs and PU, resulting in a well-dispersed distribution of PLGA NPs in the monolithic nanofiber scaffolds. Excellent antibacterial properties against Escherichia coli were found in both PU/PEO and PEO nanofiber scaffolds. This study of incorporating gentamicin-encapsulated PLGA NPs into fiber scaffolds provides insights for achieving successful incorporation of drug-encapsulated polymeric NPs into fiber scaffolds. This offers a promising microfabrication technology for delivery of therapeutic molecules with controlled release for biomedical applications. [ABSTRACT FROM AUTHOR]

Native and carbonized freeze‐cast bacterial cellulose‐alginate (BC‐ALG) foams possess an ice‐templated honeycomb‐like architecture with remarkable properties. Their unique pore morphology consists of two levels of porosity: 20–50 µm diameter pores between, and 0.01–10 µm diameter pores within the cell‐walls. The mechanical properties of the BC‐ALG foams, a Young's modulus of up to 646.2 ± 90.4 kPa and a compressive yield strength of up to 37.1 ± 7.9 kPa, are high for their density and scale as predicted by the Gibson–Ashby model for cellular materials. Carbonizing the BC‐ALG foams in an inert atmosphere at 1000–1200 °C in a second processing step, both pore morphology and mechanical properties of the BC‐ALG remain well preserved with specific mechanical properties that are higher than those reported in the literature for similar foams. Also the electrical conductivity of the BC‐ALG foams is high at 1.68 ± 0.04 S cm−1 at a density of only 0.055 g cm−3, and is found to increase with density as predicted, and as a function of the degree of carbonization determined by both carbonization temperature and atmosphere. The property profile makes freeze‐cast BC‐ALG foams and their carbonized foams attractive for energy applications and as a sorbent. [ABSTRACT FROM AUTHOR]

Introduction: Studies have confirmed that parts of the non-coding genes in the human genome play an important role in the pathogenesis and metastasis of prostate cancer. Among them, long non-coding RNAs (lncRNAs) are vitally involved in the biological regulation of prostate cancer. In addition, lncRNAs are closely associated with the recurrence, metastasis and prognosis of prostate cancer. However, the molecular pathogenesis of lncRNAs in regulating cell growth and metastasis of prostate cancer remains unclear. Therefore, this study was designed to explore the function and mechanism of lncRNA RAMS11 in cell growth and metastasis of prostate cancer. Methods: Prostate cancer and para-carcinoma tissue samples were obtained from 42 patients who were diagnosed from March 2013 to September 2014 at Quanzhou First Hospital Affiliated to Fujian Medical University. Microarray experiments and real-time polymerase chain reaction (PCR) measured the expression of lncRNA. RWPE-2, LNCap, PC3 and DU145 cells were used for an in vitro model. Results: The expression of lncRNA RAMS11 was up-regulated in prostate cancer tissue samples. LncRNA RAMS11 promoted cell growth and metastasis of prostate cancer cells. Down-regulation of lncRNA RAMS11 attenuated cell growth and metastasis of prostate cancer cells. We also demonstrated that lncRNA RAMS11 bound to CBX4 to activate expression of Top2α. LncRNA RAMS11 promoted tumor growth of prostate cancer in the mouse model. The inhibition of CBX4 attenuated the pro-cancer effects of lncRNA AMS11 in prostate cancer cells, while the activation of Top2α attenuated the anti-cancer effects of si-lncRNA RAMS11 in prostate cancer cells. Discussion: Our results indicated that lncRNA RAMS11 promoted cell growth and metastasis of prostate cancer by CBX4 complex via binding to Top2α, and might be developed for the treatment of prostate cancer. [ABSTRACT FROM AUTHOR]

Accumulating evidence have suggested the function of long noncoding RNAs as crucial players in the pathogenesis of prostate cancer (PC), a urologic tumor in male with poor prognosis. This study was designed to explore the functions of long intergenic noncoding RNA 00844 (LINC00844) in PC progression. The expression of LINC00844 and glutathione S‐transferase P1‐1 (GSTP1) was detected by reverse transcription quantitative polymerase chain reaction, followed by the identification of the relationship among LINC00844, GSTP1, and early B cell factor 1 (EBF1) by dual luciferase reporter gene assay, RNA immunoprecipitation assay, electrophoretic mobility shift assay, and chromatin immunoprecipitation assay. Using loss‐ and gain‐of‐function assays, the effects of LINC00844, GSTP1, and EBF1 on the biological characteristics of PC cells were assessed by cell counting kit‐8 assay, 5‐ethynyl‐2′‐deoxyuridine assay, and flow cytometry. Lastly, the results from in vitro experiments were verified in vivo by establishing a xenograft tumor model in nude mice. LINC00844 and GSTP1 both displayed low expression in PC tissues and cells. LINC00844 positively regulated the expression of GSTP1 via recruiting EBF1. Overexpression of LINC00844 reduced proliferation and elevated apoptosis of PC cells through recruiting EBF1, which subsequently upregulated GSTP1. In vivo experiments confirmed that LINC00844 or GSTP1 upregulation attenuated tumor growth. LINC00844 elevated GSTP1 expression by recruiting EBF1 to the promoter region of GSTP1, thereby suppressing PC progression. Hence, LINC00844 is a novel therapeutic target for the development of new treatment protocols for PC. [ABSTRACT FROM AUTHOR]

The design and development of novel methodologies and customized materials to fabricate patient‐specific 3D printed organ models with integrated sensing capabilities can yield advances in smart surgical aids for preoperative planning and rehearsal. Here, 3D printed prostate models are demonstrated with physical properties of tissue and integrated soft electronic sensors using custom‐formulated polymeric inks. The models show high quantitative fidelity in static and dynamic mechanical properties, optical characteristics, and anatomical geometries to patient tissues and organs. The models offer tissue‐mimicking tactile sensation and behavior and thus can be used for the prediction of organ physical behavior under deformation. The prediction results show good agreement with values obtained from simulations. The models also allow the application of surgical and diagnostic tools to their surface and inner channels. Finally, via the conformal integration of 3D printed soft electronic sensors, pressure applied to the models with surgical tools can be quantitatively measured. [ABSTRACT FROM AUTHOR]

Objective. Diabetic nephropathy (DN) is a common microvascular complication of diabetes mellitus, and insulin therapy has many side effects in the treatment of DN. Islet transplantation has emerged as a promising therapy for diabetic patients. This study was established to investigate its advantageous effects in a rat model of early DN. Methods. Streptozotocin was administered to the rats to induce diabetes. Twelve weeks later, the diabetic rats were divided into 3 groups: the islet-transplanted group (IT group), the insulin-treated group (IN group), and the untreated group (DN group). Renal injury and kidney structure were assessed by urinalysis and transmission electron microscopy (TEM) detection. Immunohistochemical staining and western blotting were performed to assess renal fibrosis levels. Results. The early DN features were reversed and the glomerular filtration barrier and basement membrane structures were improved at 4 weeks after islet transplantation. The urine microalbumin-to-creatinine ratio (ACR), protein-to-creatinine ratio, and mean thickness of the glomerular basement membrane (GBM) were significantly decreased in the IT group. The expression of renal fibrotic factors was also significantly decreased. Conclusions. These data suggest that early DN can be reversed after islet transplantation, and they may facilitate the development of a clinical therapeutic strategy for human diabetes mellitus. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is a unique nanofibrous biomaterial which can have applications in many engineering fields. BC possesses excellent mechanical properties and biocompatibility and can be engineered in various forms from nano to macro scales. BC based nanocomposites can be manipulated to improve their properties and/or functionalities. Such materials can be categorized as high-strength materials as well as materials for plant biomimicking, biomedical, electrically conductive, catalysis, optical, luminescent, proton conductive, separating, antimicrobial, thermo-responsive, and other applications. The review presented here focuses on various fabrication methods used and novel applications of BC based nanocomposites that are expected to be commercialized. [ABSTRACT FROM AUTHOR]

This study presents the effect of biodegradation, in a composting medium, on properties of membrane-like crosslinked and noncrosslinked polyvinyl alcohol (PVA) and nanocomposites. The composting was carried out for 120 days and the biodegradation of these materials was characterized using various techniques. The changes in the PVA resin and nanocomposite surface topography and microstructure during composting were also characterized. The results from the analyses suggest biodegradation of PVA based materials in compost medium was mainly by enzymes secreted by fungi. The results also indicate that the enzymes degraded the amorphous regions of the specimens first and that the PVA crystallinity played an important role in its biodegradation. The surface roughness of the specimens was seen to increase with composting time as the microbial colonies grew which in turn facilitated further microorganism growth. All specimens broke into small pieces between 90 and 120 days of composting as a result of deep biodegradation. Glyoxal and malonic acid crosslinking decreased the PVA biodegradation rate slightly. Addition of highly crystalline microfibrillated cellulose and naturally occurring halloysite nanotubes in PVA based nanocomposites also decreased the biodegradation rate. The three factors: PVA crystallinity, crosslinking and additives, may be utilized effectively to extend the life of these materials in real life applications. [ABSTRACT FROM AUTHOR]

Halloysite nanotubes (HNTs) based thin membrane-like fully biodegradable nanocomposites were produced by blending individualized HNT dispersion with polyvinyl alcohol (PVA). Stable individualized HNT dispersion was obtained using several separation techniques, sequentially, prior to blending with PVA. PVA was crosslinked using malonic acid (MA) as crosslinker and phosphoric acid as catalyst, to increase the mechanical and thermal properties of HNT-PVA nanocomposites. Crosslinking was also intended to make PVA water-insoluble and hence more useful in commercial applications. Examination of the composites indicated that HNTs were uniformly dispersed in both PVA as well as crosslinked PVA. Excellent mechanical properties of the HNT-PVA nanocomposites were achieved. These nanocomposites are intended to be composted at the end of their life rather than ending up in landfills as most of today's traditional petroleum based non-biodegradable plastics. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC)-based membrane-like biodegradable composites were produced by immersing wet BC pellicles in polyvinyl alcohol (PVA) solution. The BC content in the BC-PVA composites can be adjusted by varying the concentration of PVA solution. Chemical cross-linking of PVA was carried out using glutaraldehyde to increase the mechanical properties of the composites as well as to make the PVA partially to highly water insoluble. Examination by scanning electron microscopy indicated that the PVA not only penetrated the BC network, but also filled the pores within the BC pellicle. Attenuated total reflectance-Fourier transform infrared spectroscopy showed that acetal linkages could be formed in the BC-PVA composites by a cross-linking reaction. Sol-gel results indicated that cross-linking reaction increasingly made PVA insoluble in water resulting in higher gel (cross-linked fraction) content in the PVA. Wide-angle X-ray diffraction results showed decreased crystallinity in cross-linked BC and PVA, as expected. It was also found that crystal size was smaller in PVA after cross-linking. The BC-PVA composites had excellent tensile properties and cross-linking increased these properties further. Thermogravimetric analysis showed higher thermal stability for BC-PVA composites compared to PVA. The cross-linked specimens, especially the highly cross-linked ones, showed even higher thermal stability. The methods developed in this study make it possible to control the PVA content in the composites as well as the cross-linking level of PVA. These composites could be good candidates for replacing traditional non-biodegradable plastics. [ABSTRACT FROM AUTHOR]

Bioprinting: 3D Printed Organ Models with Physical Properties of Tissue and Integrated Sensors (Adv. 3D printed sensors, 3D printing, organ models, soft materials, surgical aids Keywords: 3D printed sensors; 3D printing; organ models; soft materials; surgical aids EN 3D printed sensors 3D printing organ models soft materials surgical aids 1 1 1 08/19/21 20180301 NES 180301 In article number 1700235, Robert M. Sweet, Michael C. McAlpine, and co-workers designed and developed 3D printed organ models with physical properties of tissue and integrated sensors for surgical planning and rehearsal. [Extracted from the article]