Hydrogels are three-dimensional materials that can withstand a great amount of water incorporation while maintaining integrity. This allows hydrogels to be very unique biomedical materials, ...especially for drug delivery. Much effort has been made to incorporate hydrophilic molecules in hydrogels in the field of drug delivery, while loading of hydrophobic drugs has not been vastly studied. However, in recent years, research has also been conducted on incorporating hydrophobic molecules within hydrogel matrices for achieving a steady release of drugs to treat various ailments. Here, we summarize the types of hydrogels used as drug delivery vehicles, various methods to incorporate hydrophobic molecules in hydrogel matrices, and the potential therapeutic applications of hydrogels in cancer.
This review provides an overview of the environmental impacts of combustion-based electricity generation technologies from six different energy sources, hard coal, brown coal, natural gas, diesel, ...landfill gas, and wood biomass, using the compiled information from life cycle assessment (LCA) studies. Hard coal has the highest global warming and ecotoxicity impacts, while brown coal and diesel both have high impacts in three out of 10 impact categories. Energy recovery from landfills gas exhibits a great potential to reduce the adverse impacts of landfills without the energy recovery although the level of reduction depends on the energy recovery technologies. The reduction potential of wood biomass-based electricity shows the variability affected by the efficiency of electricity generation and transport distance of the biomass. The application of carbon capture and storage (CCS) technologies to current power generation systems demonstrates great reduction potential, particularly in global warming impact with the extent of reduction varying with the applied CCS technologies. This study points out the necessity for standardization of the LCA method for a better comparison of impact assessment results for different fuel sources. An integrated method of LCA with a geographic information system (GIS) is suggested to understand the spatial variability of the impacts of power stations and to investigate the synergetic impacts that could be induced by the close geographical proximity of power stations.
Nanogels are hydrogels formed by connecting nanoscopic micelles dispersed in an aqueous medium, which give an opportunity for incorporating hydrophilic payloads to the exterior of the micellar ...networks and hydrophobic payloads in the core of the micelles. Biomedical and pharmaceutical applications of nanogels have been explored for tissue regeneration, wound healing, surgical device, implantation, and peroral, rectal, vaginal, ocular, and transdermal drug delivery. Although it is still in the early stages of development, due to the increasing demands of precise nanogel production to be utilized for personalized medicine, biomedical applications, and specialized drug delivery, 3D printing has been explored in the past few years and is believed to be one of the most precise, efficient, inexpensive, customizable, and convenient manufacturing techniques for nanogel production.
This study integrates National Pollutant Inventory emission data and geographical information system (GIS) to analyse the environmental impacts of 197 Australian thermal power stations. ReCiPe 2016 ...hierarchist method was used to investigate mid and endpoint impacts and found that 93.3% of the total midpoint impacts of fossil fuel sources were attributed to global warming impacts due to high CO2 emissions, whereas those of renewable energy technologies were driven by global warming and terrestrial ecotoxicity impacts with contribution rates of 46.2% and 47.8%, respectively. Brown coal had the highest mid and endpoint impacts per MWh electricity, whereas sewage gas and landfill gas performed the lowest midpoint and endpoint impacts, respectively. Total endpoint impacts of fossil fuel sources were in the order of brown coal > black coal > diesel > natural gas, while sewage gas > bagasse > landfill gas for renewables. It is estimated that total CO2 emissions from Australian electricity generation can be reduced by 30% when renewable electricity generation increases from 17.1% to 50% of the total electricity mix. Since the majority of coal power stations are located in high population areas, the potential impacts in these areas could be a concern.
•GIS is integrated for environmental impact assessment of electricity generation.•Fossil fuel electricity generation has high global warming impacts.•Renewable electricity generation has high terrestrial ecotoxicity impact.•Overall environmental impacts are the highest for brown coal-fired electricity.•Electricity generation may have impacts on Australian population in some areas.
Chemotherapy and radiation remain as mainstays in the treatment of a variety of cancers globally, yet some therapies exhibit limited specificity and result in harsh side effects in patients. Brain ...tissue differs from other tissue due to restrictions from the blood–brain barrier, thus systemic treatment options are limited. The focus of this review is on nanogels as local and systemic drug delivery systems in the treatment of brain cancer. Nanogels are a unique local or systemic drug delivery system that is tailorable and consists of a three-dimensional polymeric network formed via physical or chemical assembly. For example, thermosensitive nanogels show promise in their ability to incorporate therapeutic agents in nano-structured matrices, be applied in the forms of sprays or sols to the area from which a tumor has been removed, form adhesive gels to fill the cavity and deliver treatment locally. Their usage does come with complications, such as handling, storage, chemical stability, and degradation. Despite these limitations, the current ongoing development of nanogels allows patient-centered treatment that can be considered as a promising tool for the management of brain cancer.
Poly(ethylene glycol)-block-poly(d,l-lactic acid) (PEG-b-PLA) micelles act as a 3-in-1 nanocontainer for three poorly water-soluble drugs–paclitaxel, 17-allylamino-17-demethoxygeldanamycin, and ...rapamycin (PTX/17-AAG/RAPA)–for cancer therapy. In a LS180 human colon xenograft model, a single intravenous (IV) injection of 3-in-1 PEG-b-PLA micelles reduced tumor volume by 1.6-fold with <10% body weight change. In a second step, IV injection of poly(ethylene glycol)-block-poly(ε-caprolactone) (PEG-b-PCL) micelles carrying a carbocyanine dye (1,1′-dioctadecyl tetramethyl indotricarbocyanine iodide (DiR)) after 48 h resulted in a 2.1-fold higher near-infrared (NIR) optical signal from excised solid tumors versus a negative control, presumably due to a reduction in tumor cell density and interstitial tumor pressure. Thus, a tandem of 3-in-1 PEG-b-PLA and PEG-b-PCL micelles could potentially be used for neoadjuvant cancer therapy and tumor-primed NIR optical imaging for intraoperative surgical guidance in oncology, offering a promising multimodal strategy for cancer therapy and imaging.
Rectal artesunate suppositories are a useful option for pre-referral treatment of severe malaria, specifically in children under 6 years of age in remote malaria-endemic areas. The main challenges ...are to improve the solubility of drugs in the rectal fluids and prevent the product from turning rancid or melting in a tropical climate. In this short proof-of-concept study, three types of rectal suppositories of artesunate were prepared: (i) polyethylene glycol (PEG)-based suppositories carrying free artesunate (non-modified artesunate), (ii) PEG-based suppositories carrying artesunate-loaded micelles and (iii) 3D-printed suppositories carrying a PEG/artesunate mixture. Physical parameters of suppositories, release profiles of artesunate (the fastest to the slowest: ii≥i>iii) and thermostability (the most stable to the least stable: iii>ii>i) of suppositories at increased temperature were assessed to determine the advantages and disadvantages of each formulation.
This study was conducted to estimate the effects of exogenous protease on performance, economic evaluation, nutrient digestibility, fecal score, intestinal morphology, blood profile, carcass traits, ...and meat quality in broilers fed normal diets and diets considered with matrix value. A total of 90, one-day-old Arbor Acres broiler chickens were randomly allocated to 3 dietary treatments with 6 replicates and each replicate of 5 broiler chickens. Treatments were as follows: 1) Basal diet (positive control, PC), 2) Basal diet formulated with full ProAct 360 matrix at 50 g/MT without addition of ProAct 360 (negative control, NC), 3) NC + 50 g/MT ProAct 360 (PA). Supplementation of exogenous protease to nutrient deficient NC diet by matrix values (PA) tended to increase growth performance and significantly improved intestinal morphology compared with the NC group. The PA group had significantly lower fecal score, and higher ATTD of crude protein and amino acids than those of the NC group. Furthermore, supplementation of exogenous protease to NC diet decreased feed cost, resulting in improved profit margin. However, there was no significant difference on carcass yield and relative organ weight. In conclusion, supplementation of exogenous protease using matrix value could be used as economic additive to improve growth, profit margin, digestibility, and gut health in broiler chickens.
Abstract Noninvasive near-infrared (NIR) fluorescence imaging is a promising technique for the intraoperative assessment of solid tumor removal. We incorporated a lipophilic NIR probe, ...1,1′-dioctadecyltetramethyl indotricarbocyanine iodide (DiR), in poly(ethylene glycol)- b -poly(ɛ-caprolactone) (PEG- b -PCL) micelles, resulting in DiR solubilization in water, occupying nanoscopic PEG- b -PCL micelles. DiR in a self-quenched or nonquenched state showed different kinetics of release from PEG- b -PCL micelles in vitro; however, both obtained high tumor delineation (tumor-to-muscle ratio of 30–43 from collected organs). These results suggest that PEG- b -PCL micelles with DiR are a promising nanosized imaging agent that will provide a basis for enhanced surgical guidance via NIR visualization of tumors. From the Clinical Editor In this paper, noninvasive near-infrared fluorescence imaging coupled with specific lipophilic probes is discussed as a promising technique for intraoperative assessment of solid tumor removal, leading to optimized outcomes for in toto removal of tumors.
Steam methane reforming (SMR) using natural gas is the most commonly used technology for hydrogen production. Industrial hydrogen production contributes to pollutant emissions, which may differ from ...the theoretical estimates due to process conditions, type and state of installed pollution control equipment. The aim of this study was to estimate the impacts of hydrogen production using facility-level real emissions data collected from multiple US EPA databases. The study applied the ReCiPe2016 impact assessment method and considered 12 midpoint and 14 endpoint impacts for 33 US SMR hydrogen production facilities. Global warming impacts were mostly driven by CO2 emissions and contributed to 94.6% of the endpoint impacts on human health, while global warming impact on terrestrial ecosystems contributed to 98.3% of the total endpoint impacts on ecosystems. The impacts estimated by direct emissions from the 33 facilities were 9.35 kg CO2e/kg H2 which increased to 11.2 kg CO2e/kg H2 when the full life cycle of hydrogen production including upstream emissions was included. The average global warming impact could be reduced by 5.9% and 11.1% with increases in hydrogen production efficiency by 5% and 10%, respectively. Potential impact reductions are also found when natural gas hydrogen production feedstock is replaced by renewable sources, with the greatest reduction of 78.1% found in hydrogen production via biomass gasification, followed by 68.2% reduction in landfill gas and 53.7% reduction in biomethane-derived hydrogen production.
•Impacts of hydrogen production using facility-level emissions data were assessed.•Production efficiency is the key factor to reducing greenhouse gas emissions.•Greenhouse gas emission from direct emissions are estimated at 9.35 kg CO2e/kg H2.•Renewable energy can reduce impacts with biomass gasification reducing impacts by 78%.•Substituting natural gas with landfill gas can reduce climate change impacts by 68%.
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