Search

Tellurium (Te) is the heaviest stable chalcogen and is a rare element in Earth's crust (one to five ppb). It was discovered in gold ore from mines in Kleinschlatten near the present-day city of Zlatna, Romania. Industrial and other applications of Te focus on its inorganic forms. Tellurium can be toxic to animals and humans at low doses. Chronic tellurium poisoning endangers the kidney, liver, and nervous system. However, Te can be effective against bacteria and is able to destroy cancer cells. Tellurium can also be used to develop redox modulators and enzyme inhibitors. Soluble salts that contain Te had a role as therapeutic and antimicrobial agents before the advent of antibiotics. The pharmaceutical use of Te is not widespread due to the narrow margin between beneficial and toxic doses, but there are differences between the measure of toxicity based on the Te form. Nano-tellurium (Te-NPs) has several applications: it can act as an adsorptive agent to remove pollutants, and it can be used in antibacterial coating, photo-catalysis for the degradation of dyes, and conductive electronic materials. Nano-sized Te particles are the most promising and can be produced in both chemical and biological ways. Safety assessments are essential to determine the potential risks and benefits of using Te compounds in various applications. Future challenges and directions in developing nano-materials, nano-alloys, and nano-structures based on Te are still open to debate. [ABSTRACT FROM AUTHOR]

Tellurium (Te) is the heaviest stable chalcogen and is a rare element in Earth’s crust (one to five ppb). It was discovered in gold ore from mines in Kleinschlatten near the present-day city of Zlatna, Romania. Industrial and other applications of Te focus on its inorganic forms. Tellurium can be toxic to animals and humans at low doses. Chronic tellurium poisoning endangers the kidney, liver, and nervous system. However, Te can be effective against bacteria and is able to destroy cancer cells. Tellurium can also be used to develop redox modulators and enzyme inhibitors. Soluble salts that contain Te had a role as therapeutic and antimicrobial agents before the advent of antibiotics. The pharmaceutical use of Te is not widespread due to the narrow margin between beneficial and toxic doses, but there are differences between the measure of toxicity based on the Te form. Nano-tellurium (Te-NPs) has several applications: it can act as an adsorptive agent to remove pollutants, and it can be used in antibacterial coating, photo-catalysis for the degradation of dyes, and conductive electronic materials. Nano-sized Te particles are the most promising and can be produced in both chemical and biological ways. Safety assessments are essential to determine the potential risks and benefits of using Te compounds in various applications. Future challenges and directions in developing nano-materials, nano-alloys, and nano-structures based on Te are still open to debate.

Boron nanoparticles have emerged as promising nanomaterials with a wide array of applications in the biomedical, industrial, and environmental fields. However, the potential impact of these nanoparticles on aquatic organisms is not yet known. In the present study, the comparative impact of boron nitride nanoparticles and its bulk form is investigated on two freshwater algae. For this purpose, the effect on the physiological index, cellular morphology, and biochemistry profiles are examined. In Chlorella vulgaris, nano form of boron nitride is found to reduce the growth more (40%) than its bulk form (with ~ 25% growth reduction) at 50 mgl−1 treatment level. While in case of Coelastrella terrestris, 40% reduction under nano form and 33.33% reduction under bulk form is observed at 100 mgl−1 of boron nitride. Chlorophyll and carotenoid levels were also reduced under nanoparticles compared to the bulk. Proline, lactate dehydrogenase, and malondialdehyde assay were found significantly high under nanoparticle exposure. Additionally, increased catalase and superoxide dismutase enzyme activity under nanoparticle exposure revealed that the antioxidant system was activated in both the algae to eliminate the adverse influence of reactive oxygen species. The shading effect and aggregation of nanoparticles over the surface of algal cells are also important factors in attributing toxicity which are confirmed through the compound, TEM, and SEM micrographs. The study suggests that the nano form is more toxic than the bulk form and toxicity is concentration-dependent. [ABSTRACT FROM AUTHOR]

The widespread use of fertilizers is a result of the increased global demand for food. The commonly used chemical fertilizers may increase plant growth and output, but they have deleterious effects on the soil, the environment, and even human health. Therefore, nanofertilizers are one of the most promising solutions or substitutes for conventional fertilizers. These engineered materials are composed of nanoparticles containing macro- and micronutrients that are delivered to the plant rhizosphere in a regulated manner. In nanofertilizers, the essential minerals and nutrients (such as N, P, K, Fe, and Mn) are bonded alone or in combination with nano-dimensional adsorbents. This review discusses the development of nanotechnology-based smart and efficient agriculture using nanofertilizers that have higher nutritional management, owing to their ability to increase the nutrient uptake efficiency. Additionally, the synthesis and mechanism of action of the nanofertilizers are discussed, along with the different types of fertilizers that are currently available. Furthermore, sustainable agriculture can be realised by the targeted delivery and controlled release of nutrients through the application of nanoscale active substances. This paper emphasises the successful development and safe application of nanotechnology in agriculture; however, certain basic concerns and existing gaps in research need to be addressed and resolved. [ABSTRACT FROM AUTHOR]

Incomplete separation and recycling of nanoparticles are causing undesirable nanopollution and thus raising great concerns with regard to nanosafety. Since microorganisms are important regulator of physiological processes in many organisms, the interaction between nanopollution and microbial metabolomics and the resultant impact on the host's health are important but unclear. To investigate how typical nanopollution perturbs microbial growth and metabolism, Escherichia coli (E. coli) in vitro was treated with six water-dispersible nanomaterials (nanoplastic, nanosilver, nano-TiO2, nano-ZnO, semiconductor quantum dots (QDs), carbon dots (CDs)) at human-/environment-relevant concentration levels. The nanomaterials exhibited type-specific toxic effects on E. coli growth. Global metabolite profiling was used to characterize metabolic disruption patterns in the model microorganism exposed to different nanopollutants. The percentage of significant metabolites (p < 0.05, VIP > 1) accounted for 6%–38% of the total 293 identified metabolites in each of the nanomaterial-contaminated bacterial groups. Metabolic results also exhibited significant differences between different nanopollutants and dose levels, revealing type-specific and untypical concentration-dependent metabolic responses. Key metabolites responsive to nanopollution exposures were mainly involved in amino acid and purine metabolisms, where 5, 4, and 7 significant metabolic features were included in arginine and proline metabolism, phenylalanine metabolism, and purine metabolism, respectively. In conclusion, this study horizontally compared and demonstrated how typical nanopollution perturbs microbial growth and metabolomics in a type-specific manner, which broadens our understanding of the ecotoxicity of nanopollutants on microorganisms. [ABSTRACT FROM AUTHOR]

The widespread use of fertilizers is a result of the increased global demand for food. The commonly used chemical fertilizers may increase plant growth and output, but they have deleterious effects on the soil, the environment, and even human health. Therefore, nanofertilizers are one of the most promising solutions or substitutes for conventional fertilizers. These engineered materials are composed of nanoparticles containing macro- and micronutrients that are delivered to the plant rhizosphere in a regulated manner. In nanofertilizers, the essential minerals and nutrients (such as N, P, K, Fe, and Mn) are bonded alone or in combination with nano-dimensional adsorbents. This review discusses the development of nanotechnology-based smart and efficient agriculture using nanofertilizers that have higher nutritional management, owing to their ability to increase the nutrient uptake efficiency. Additionally, the synthesis and mechanism of action of the nanofertilizers are discussed, along with the different types of fertilizers that are currently available. Furthermore, sustainable agriculture can be realised by the targeted delivery and controlled release of nutrients through the application of nanoscale active substances. This paper emphasises the successful development and safe application of nanotechnology in agriculture; however, certain basic concerns and existing gaps in research need to be addressed and resolved.

The possibility of employing computational approaches like nano-QSAR or nano-read-across to predict nanomaterial hazard is attractive from both a financial, and most importantly, where in vivo tests are required, ethical perspective. In the present work, we have employed advanced Machine Learning techniques, including stacked model ensembles, to create nano-QSAR tools for modeling the toxicity of metallic and metal oxide nanomaterials, both coated and uncoated and with a variety of different core compositions, tested at different dosage concentrations on embryonic zebrafish. Using both computed and experimental descriptors, we have identified a set of properties most relevant for the assessment of nanomaterial toxicity and successfully correlated these properties with the associated biological responses observed in zebrafish. Our findings suggest that for the group of metal and metal oxide nanomaterials, the core chemical composition, concentration and properties dependent upon nanomaterial surface and medium composition (such as zeta potential and agglomerate size) are significant factors influencing toxicity, albeit the ranking of different variables is sensitive to the exact analysis method and data modeled. Our generalized nano-QSAR ensemble models provide a promising framework for anticipating the toxicity potential of new nanomaterials and may contribute to the transition out of the animal testing paradigm. However, future experimental studies are required to generate comparable, similarly high quality data, using consistent protocols, for well characterized nanomaterials, as per the dataset modeled herein. This would enable the predictive power of our promising ensemble modeling approaches to be robustly assessed on large, diverse and truly external datasets. [ABSTRACT FROM AUTHOR]

The rapid development in nanotechnology and incorporation of engineered nano-particles (ENPs) in a wide range of consumer products releasing the massive quantities of ENPs in different environmental compartments. The released ENPs from nano-enabled products during their life cycle raising environmental health and safety issues. This review addresses the recent state of knowledge regarding the ENPs ecotoxicity to various organisms lying at different trophic levels. Studies show that reactive oxygen species (ROS) mediated oxidative stress is the primary mechanism of nano-toxicity, either through physical damage by direct contact or release of toxic ions after ENPs dissolution process. Moreover, ENPs uptake, transformation and toxicity on physio-morphological, biochemical and molecular levels in primary producers of terrestrial environment (plants) were also reviewed. Additionally, the intrinsic detoxification mechanism in plants in response to ENPs accumulation was also examined. In the end different sustainable approaches such as biogenic synthesis, clay minerals role, biochar application, bioremediation, and legislative measures are proposed for effective handling and treatment of nano-wastes to get the maximum benefits of nanotechnology with minimum negative outcomes. [ABSTRACT FROM AUTHOR]

Backgrounds: In this study, Jellyfish extract at immunity reaction (JEI) captured Ag citrate nanoparticles (Ag citrate NPs) and reduce toxicity was investigated. Methods: JEI obtained from Aurelia aurita was used to assess the capture of Ag citrate NPs (10 mg/L, 2 mg/L) during 24 h, and the toxicity of JEI was assessed using a human cell line BEAS-2B. Results: JEI was to reduce Ag citrate NPs in water by 34.55% (10 mg/L) after 1 h and by 40.62 ~ 41% (2 mg/L, 10 mg/L) after 24 h. When the BEAS-2B was exposed to 2 mg/L of Ag citrate NPs mixed with JEI showed increase 33.97% survival than 2 mg/L of Ag citrate NPs (0%). Furthermore, the apoptosis-related genes (p53, Bcl2, and Bax) showed no significant difference in expression upon exposure to JEI, compared to the control. Conclusion: JEI is to capture Ag citrate NPs and reduce its nano-toxicity. Therefore, such ability of JEI is likely to prove useful in the control of AgNPs flowing into the aquatic ecosystem. [ABSTRACT FROM AUTHOR]

Materials of nano-dimensions are gaining popularity due to their inherent properties such as high reactivity, mobility and surface area. Environmental bioremediation by employing microbial platforms is one of the most rapidly growing areas of nano-biotechnology. Nanoparticles synthesized using biological entities such as yeast, bacteria, fungi, algae and plants are referred to as biogenic nanoparticles. Owing to their nontoxicity, biologically synthesized nanoparticles have emerged as a sustainable alternative to chemically synthesized nanoparticles. In the past few years, several biogenic nanoparticles have been developed for potential application in medicine and environmental remediation. Biogenic nanoparticles such as biogenic manganese oxide (BioMnOx), biogenic nano-magnets, bio-palladium nanocrystals and biogenic iron species have proven to be effective for the removal of several micro-pollutants, heavy metals, recalcitrant pollutants and halogenated compounds. Nano-bioremediation could emerge as a better, safer, ecofriendly and cost-effective technology, which can greatly influence the domain of environmental remediation in the long run. This study reviews the synthesis, classification and applications of microbial nanoparticles for environmental bioremediation. [ABSTRACT FROM AUTHOR]

The rapid expansion of nanotechnology has led to the use of nanomaterials in various consumer products. Among these nanomaterials, nano-silver has gained considerable attention as an excellent candidate due to its unique physical and chemical properties. However, studies related to their effects on the ecosystem are still insufficient. Thus, the present study was designed to explore in length the toxic effects of nano-silver on Nostoc muscorum and Plectonema boryanum in terms of dose-dependent cellular growth, cell viability, bioaccumulation/biodistribution and changes in protein profile. The exposure to nano-silver resulted in 8–9 times less reduction in cell viability as compared to silver nitrate, suggesting the formation of aggregates in test medium and low release of silver ions from nano-silver. Morphological changes under stress were studied by scanning electron microscopy, and corresponding elemental silver was monitored by energy-dispersive X-ray spectroscopy. Significant uptake and bioaccumulation/biodistribution of both forms of silver were elucidated by atomic absorption spectroscopy and transmission electron microscopy, respectively. This study demonstrated that silver nitrate was more toxic as compared to nano-silver and both exerted toxic effects in a dose- and species-specific manner. The present study suggests that observed toxicity of nano-silver might be due to the silver ions released from nano-silver. Thus, the release of silver from various consumer products in the environment should be controlled and carefully monitored at regular interval. [ABSTRACT FROM AUTHOR]

The current study checks the effect of various concentrations of dietary graphene oxide (GO) nano-sheets on the development of Drosophila melanogaster. GO was synthesized and characterized by XRD, FTIR, FESEM, and TEM analytical techniques. Various concentrations of GO were mixed with the fly food and flies were transferred to the vial. Various behavioral and morphological as well as genetic defects were checked on the different developmental stages of the offspring. In the larval stage of development, the crawling speed and trailing path change significantly than the control. GO induces the generation of oxygen radicals within the larval hemolymph as evidenced by nitroblue tetrazolium assay. GO induces DNA damage within the gut cell, which was detected by Hoechst staining and within hemolymph by comet assay. Adult flies hatched after GO treatment show defective phototaxis and geotaxis behavior. Besides behavior, phenotypic defects were observed in the wing, eye, thorax bristles, and mouth parts. At 300 mg/L concentration, wing spots were observed. Altogether, the current study finds oral administration of GO which acts as a mutagen and causes various behavioral and developmental defects in the offspring. Here for the first time, we are reporting GO, which acts as a teratogen in Drosophila, besides its extensive medical applications. [ABSTRACT FROM AUTHOR]

Abstract The interactions of natural drug functionalized metal nanoparticles with DNA plays a pivotal role in developing effective therapeutic agents having a wide range of potential biomedical applications. The focus of this study was to decipher the binding mechanism of diosmin capped gold nanoparticles (DM-AuNPs) with calf thymus DNA (ctDNA) through a combination series of spectroscopic and calorimetric studies. The gold nanoparticles were successfully synthesized by the facile one-pot synthesis using DSM as a capping and reducing agent. The DM-AuNPs were characterized using UV–Visible spectroscopy, XRD, FTIR, DLS and HRTEM analysis confirming the formation of stable AuNPs with an average size of 30 ± 3 nm. A series of experiments such as UV–Vis absorbance, fluorescence dye displacement studies, temperature melting and viscosity analysis unravelled the binding mode of DM-AuNPs by establishing a typical groove binding mode upon its complexation with ctDNA. The CD and FTIR measurements provided clear-cut evidences regarding the conformational alterations and the stability of ctDNA double helical structure in the presence of DM-AuNPs. The thermodynamic binding parameters deduced from the ITC revealed that the binding was exothermic and spontaneous in nature. All these results maintained consistency with the typical groove binding fashion of DM-AuNPs and confirmed the formation of DM-AuNPs-ctDNA complex. The MTT assay revealed a moderate anti-proliferative and toxicity effects of DM-AuNPs on MCF-7 and normal human cell lines. In this context the entire results based on ctDNA-DM-AuNPs binding mechanism may facilitate sensible synthesis and designing of various synthetic/natural drug functionalized nanoparticles possessing better therapeutic and sensing efficacy with minimal toxicity. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Three-dimensional cell culture has revolutionized cellular biology research and opened the door to novel discoveries in terms of cellular behavior and response to microenvironment stimuli. Different types of 3D culture exist today, including hydrogel scaffold-based models, which possess a complex structure mimicking the extracellular matrix. These hydrogels can be made of polymers (natural or synthetic) or low-molecular weight gelators that, via the supramolecular assembly of molecules, allow the production of a reproducible hydrogel with tunable mechanical properties. When cancer cells are grown in this type of hydrogel, they develop into multicellular tumor spheroids (MCTS). Three-dimensional (3D) cancer culture combined with a complex microenvironment that consists of a platform to study tumor development and also to assess the toxicity of physico-chemical entities such as ions, molecules or particles. With the emergence of nanoparticles of different origins and natures, implementing a reproducible in vitro model that consists of a bio-indicator for nano-toxicity assays is inevitable. However, the maneuver process of such a bio-indicator requires the implementation of a repeatable system that undergoes an exhaustive follow-up. Hence, the biggest challenge in this matter is the reproducibility of the MCTS and the associated full-scale characterization of this system’s components.

Textile microfibers are the most common form of microplastic pollution and among the most dangerous to wildlife across multiple biomes. Besides toxicological challenges arising from their shapes, the morphology of fibrous materials make them excellent adsorbents and transportation media for harmful chemical pollutants and support both uptake and bioaccumulation across living organisms. The fragmentation of microfibers used in the textile industry is shown to lead to the formation of a broad range of sub-micron and nanofibers, with greater surface to volume ratio and much finer diameters, whose toxicity and environmental impact are not yet understood. Here, the impact of nanofibers on zebrafish embryos is studied to reveal risks associated with nanofiber pollution during early developmental stages. Exposure of embryos to nanofibers at a similar concentration to what has been observed in polluted water streams was found to dramatically increase apoptosis, neutrophils, and cytokine production that the chorion was unable to protect against. Furthermore, disturbed vascular basement membrane assembly in exposed embryos was detected leading to an expanded dorsal aorta diameter. These results obtained with model nanofibers demonstrate the risks of fragmented microplastics and the impact of surface properties on uptake and response by living organisms. [Display omitted] • The manufacturing of PET nanofibers for use in toxicity studies was developed. • The toxicity of PET nanofibers on developing zebrafish embryos at a concentration detected in the wild was investigated. • Increased apoptosis, inflammation and altered vascular development were detected in embryos exposed to PET nanofibers. • The zebrafish chorion was unable to protect against PET nanofiber toxicity. [ABSTRACT FROM AUTHOR]

Wear debris, of deferent sizes, shapes and quantities, generated in artificial hip and knees is largely confined to the bone and joint interface. This debris interacts with periprosthetic tissue and may cause aseptic loosening. The purpose of this review is to summarize and collate findings of the recent demonstrations on debris characterization and their biological response that influences the occurrence in implant migration. A systematic review of peer-reviewed literature is performed, based on inclusion and exclusion criteria addressing mainly debris isolation, characterization, and biologic responses. Results show that debris characterization largely depends on their appropriate and accurate isolation protocol. The particles are found to be non-uniform in size and non-homogeneously distributed into the periprosthetic tissues. In addition, the sizes, shapes, and volumes of the particles are influenced by the types of joints, bearing geometry, material combination, and lubricant. Phagocytosis of wear debris is size dependent; high doses of submicron-sized particles induce significant level of secretion of bone resorbing factors. However, articles on wear debris from engineered surfaces (patterned and coated) are lacking. The findings suggest considering debris morphology as an important parameter to evaluate joint simulator and newly developed implant materials.

Nanomaterials can become disseminated directly or indirectly into the soil ecosystem through various exposure routes. Thus, it is important to study various deposition routes of nanomaterials into the soil, as well as their toxicities. Here, we investigated the multigenerational effects of gold nanoparticles (AuNPs) on C. elegans after continuous or intermittent food intake. Following continuous exposure, significant differences were observed in the reproduction rate of C. elegans in the F2–F4 generations, which were associated with reproductive system abnormalities. However, following intermittent AuNP exposure in P0 and F3, reproductive system abnormalities and inhibited reproduction rates were observed in F2 and F3. While continuous AuNP exposure impaired reproduction from F2 to F4, intermittent exposure caused more pronounced effects on F3 worms, which may have resulted from damage during the convalescence period up through F2. These data showed the occurrence of multigenerational effects following different exposure patterns, exposure levels, and recovery periods. To our knowledge, this is the first study to demonstrate that multigenerational nano-toxicity is caused by different exposure patterns and provides insights into the unpredictable exposure scenarios of AuNPs and their adverse effects. [ABSTRACT FROM AUTHOR]

Current first-line treatments for most cancers feature a short-list of highly potent and often target-blind interventions, including chemotherapy, radiation, and surgical excision. These treatments wreak considerable havoc upon non-cancerous tissue and organs, resulting in deleterious and sometimes fatal side effects for the patient. In response, this past decade has witnessed the robust emergence of nanoparticles and, more relevantly, nanoparticle drug delivery systems (DDS), widely touted as the panacea of cancer therapeutics. While not a cure, nanoparticle DDS can successfully negotiate the clinical payoff between drug dosage and side effects by encompassing target-specific drug delivery strategies. The expanding library of nanoparticles includes lipoproteins, liposomes, dendrimers, polymers, metal and metal oxide nano-spheres and -rods, and carbon nanotubes, so do the modes of delivery. Importantly, however, the pharmaco-dynamics and –kinetics of these nano-complexes remain an urgent issue and a serious bottleneck in the transition from bench to bedside. This review addresses the rise of nanoparticle DDS platforms for cancer and explores concepts of gene/drug delivery and cytotoxicity in pre-clinical and clinical contexts.

A new method to integrate poly-DL-lactide (PLA) patterned electrospun fibers with a polydimethylsiloxane (PDMS) microfluidic chip was successfully developed via lithography. Hepatocyte behavior under static and dynamic conditions was investigated. Immunohistochemical analyses indicated good hepatocyte survival under the dynamic culture system with effective hepatocyte spheroid formation in the patterned microfluidic chip vs. static culture conditions and tissue culture plate (TCP). In particular, hepatocytes seeded in this microfluidic chip under a flow rate of 10 μL/min could re-establish hepatocyte polarity to support biliary excretion and were able to maintain high levels of albumin and urea secretion over 15 days. Furthermore, the optimized system could produce sensitive and consistent responses to nano-Ag-induced hepatotoxicity during culture. Thus, this microfluidic chip device provides a new means of fabricating complex liver tissue-engineered scaffolds, and may be of considerable utility in the toxicity screening of nanoparticles. [ABSTRACT FROM AUTHOR]

Silica nanoparticles have drawn a lot of attention for nanomedicine application, and this is attributed to their biocompatibility and ease of surface functionalization. However, successful utilization of these inorganic systems for biomedical application depends on their physicochemical properties. This study, therefore, discusses in vitro toxicity of organically modified silica nanoparticles on the basis of size, shape, and surface properties of silica nanoparticles. Spherical- and oval-shaped nanoparticles having hydroxyl and amine groups were synthesized in Tween 80 micelles using different organosilanes. Nanoparticles of similar size and morphology were considered for comparative assessment. 'As-prepared' nanoparticles were characterized in terms of size, shape, and surface properties using Zeta Sizer, transmission electron microscopy, and Fourier transform infrared to establish the above parameters. In vitro analysis in terms of nanoparticle-based toxicity was performed on J-774 (macrophage) cell line using propidium iodide-4′,6-diamidino-2-phenylindol and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. Fluorescent dye-entrapped nanoparticles were used to visualize the uptake of the nanoparticles by macrophage cells. Results from cell studies suggested low levels of toxicity for different nanoparticle formulations studied, therefore are suitable for nanocarrier application for poorly soluble molecules. On the contrary, the nanoparticles of similar size and shape, having amine groups and low net negative charge, do not exhibit any in vitro cytotoxicity. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:3943-3951, 2015 [ABSTRACT FROM AUTHOR]

Rapid advances in nanotechnology in recent years have raised concern about the occurrence, distribution, fate, and transport of nanoparticles in the environment. Sources of nanoparticles in the environment include their widespread use in a variety of engineering operations, biomedical applications, consumer goods, food and drug delivery system, and so forth. Because they can be released into the environment either as a waste product or as a byproduct of some engineered processes or applications, nanoparticles or nanoscale materials are increasingly detected in various environmental matrices. By their very nature, nanoparticles are active at molecular levels, and there is a concern that their occurrence in the environment and unintended exposure may pose an adverse risk to human health and ecology. Because of the nature of recent nanotechnology-based applications, our understanding of nanoparticle behavior in the environment is limited. The objective of this literature review is to provide a measure of understanding and to document the state of knowledge on the environmental occurrence, distribution, fate, and risk of nanoparticles. This review covers a wide range of published studies that illustrate the state of understanding about the behavior of nanoparticles in various environmental matrices such as air, soil, water, and wastewater. A brief review of the evolving regulatory framework to deal with the occurrence of nanoparticles is also included. [ABSTRACT FROM AUTHOR]

Wear debris, of deferent sizes, shapes and quantities, generated in artificial hip and knees is largely confined to the bone and joint interface. This debris interacts with periprosthetic tissue and may cause aseptic loosening. The purpose of this review is to summarize and collate findings of the recent demonstrations on debris characterization and their biological response that influences the occurrence in implant migration. A systematic review of peer-reviewed literature is performed, based on inclusion and exclusion criteria addressing mainly debris isolation, characterization, and biologic responses. Results show that debris characterization largely depends on their appropriate and accurate isolation protocol. The particles are found to be non-uniform in size and non-homogeneously distributed into the periprosthetic tissues. In addition, the sizes, shapes, and volumes of the particles are influenced by the types of joints, bearing geometry, material combination, and lubricant. Phagocytosis of wear debris is size dependent; high doses of submicron-sized particles induce significant level of secretion of bone resorbing factors. However, articles on wear debris from engineered surfaces (patterned and coated) are lacking. The findings suggest considering debris morphology as an important parameter to evaluate joint simulator and newly developed implant materials. [ABSTRACT FROM AUTHOR]

Current first-line treatments for most cancers feature a short-list of highly potent and often target-blind interventions, including chemotherapy, radiation, and surgical excision. These treatments wreak considerable havoc upon non-cancerous tissue and organs, resulting in deleterious and sometimes fatal side effects for the patient. In response,this past decade has witnessed the robust emergence of nanoparticles and, more relevantly,nanoparticle drug delivery systems (DDS), widely touted as the panacea of cancer therapeutics. While not a cure, nanoparticle DDS can successfully negotiate the clinical payoff between drug dosage and side effects by encompassing target-specific drug delivery strategies. The expanding library of nanoparticles includes lipoproteins, liposomes, dendrimers, polymers, metal and metal oxide nano-spheres and -rods, and carbon nanotubes, so do the modes of delivery. Importantly, however, the pharmaco-dynamics and -kinetics of these nano-complexes remain an urgent issue and a serious bottleneck in the transition from bench to bedside. This review addresses the rise of nanoparticle DDS [ABSTRACT FROM AUTHOR]

• Single NPS reduces H 2 -production by 53.9%, while combined NPS + PFOS decrease by 31.6%. • The combined toxicity of NPS + PFOS is antagonistic relative to single NPS. • Single NPS and combined NPS + PFOS alter the properties, structure and function of EPS. • Single NPS and combined NPS + PFOS increase permeability and induce oxidative stress. As a carrier of perfluorooctane sulfonate, nano-plastics are ubiquitous and finally enriched in the sludge, which is widely used as a raw material for the production of bioenergy (hydrogen or methane) by anaerobic digestion. However, there are still many unknowns about their metabolic toxicity to functional microbes (e.g. hydrogen-producing thermophilic bacteria). Therefore, single and combined effects of amino polystyrene (NPS: 70 nm; 0.2 mg/L) and perfluorooctane sulfonate (PFOS: 0.1, 1 and 5 mg/L) on hydrogen-producing thermophilic bacteria were investigated after exposure for 7 days at 55 °C and pH = 5.7. Single NPS exhibited obvious interference to the metabolism of thermophilic bacteria, resulting in a 53.9% reduction in hydrogen production. However, the combined NPS + PFOS produced an antagonistic effect, leading to a 31.6% reduction in hydrogen production. Nonetheless, the single and combined exposure did not alter the type of hydrogen production (acetic acid-type hydrogen fermentation). Moreover, single NPS and combined NPS + PFOS not only induced the changes of the composition of extracellular polymers (EPSs) and π bond structure of the protein in EPSs, but also decreased the activity of hydrolase in EPSs and surface charge of EPSs. Compared to single NPS exposure, NPS + PFOS-exposed thermophilic bacteria was less permeable to a semi-membrane permeable dye and produced less reactive oxygen species, but were still significantly higher than control group. In short, the main mechanisms of single NPS and combined NPS + PFOS were both to increase cell permeability and to induce oxidative stress. The addition of PFOS alleviated the toxic effect of NPS, but did not change its mechanism of toxicity. [ABSTRACT FROM AUTHOR]

A new method to integrate poly-dl-lactide (PLA) patterned electrospun fibers with a polydimethylsiloxane (PDMS) microfluidic chip was successfully developed via lithography. Hepatocyte behavior under static and dynamic conditions was investigated. Immunohistochemical analyses indicated good hepatocyte survival under the dynamic culture system with effective hepatocyte spheroid formation in the patterned microfluidic chip vs. static culture conditions and tissue culture plate (TCP). In particular, hepatocytes seeded in this microfluidic chip under a flow rate of 10 μL/min could re-establish hepatocyte polarity to support biliary excretion and were able to maintain high levels of albumin and urea secretion over 15 days. Furthermore, the optimized system could produce sensitive and consistent responses to nano-Ag-induced hepatotoxicity during culture. Thus, this microfluidic chip device provides a new means of fabricating complex liver tissue-engineered scaffolds, and may be of considerable utility in the toxicity screening of nanoparticles.