26 research outputs found
Pharmacokinetic Properties and Safety of Cadmium-Containing Quantum Dots as Drug Delivery Systems
Toxicity of Quantum Dots
Quantum dots (QD) have been deeply studied due to their physicochemical and optical properties with important advantages of a wide range biomedical applications. Nevertheless, concern prevails about its toxic effects, mainly in those QD whose core contains cadmium. Therefore, there are reports about the toxicity caused by the release of ions of cadmium and the effects related to its tiny nanometric size. The aim of this chapter is to show the evaluations about the toxicity of QD, which include studies on viability, proliferation, uptake, and distribution in vitro and in vivo models. What are the worrying toxic effects of QD? There are reports about some mechanisms of toxicity caused by QD, such as immunological toxicity, cell death (apoptosis and necrosis), genotoxicity, among others. In addition, we discuss how coating QD with passivating agents that improve their biocompatibility. Likewise, this coating modifies their size and surface charge, which are fundamental aspects of the interaction with other biomolecules. We consider highlighting information about more precise techniques and methodologies that help us to understand how QD induce damage in several biological systems
Interaction of Nanoparticles with Blood Components and Associated Pathophysiological Effects
Nanotechnology currently plays a pivotal role in several fields and has enabled substantial advances in a relatively short time. In biomedicine, nanomaterials can be potentially employed as a tool for early diagnosis and an innovative mode of drug delivery. Novel nanomaterials are currently widely manipulated without a full assessment of their potential health risks. It is commonly thought that nanomaterialsâ first contact with the organism is through the different components of the immune system. However, if the entry route is intravenous, the first contact will be with the bloodâs components (erythrocytes, platelets, white cells, plasma and complement proteins). The presence of nanomaterials within a dynamic environment such as the bloodstream can produce potential harmful effects following interaction with several blood components. The design of innovative strategies leading to the development of more hemocompatible nanomaterials is also necessary
Potential Harm of MaltodextrinâCoated Cadmium Sulfide Quantum Dots in Embryos and Fetuses
Over the past years, there has been significant interest in the study of nanoparticles for clinical applications, particularly quantum dots (QDs). However, previous studies have also shown that QDs can reach the embryo through the placenta, a natural barrier for a large variety of organic substances with diverse molecular structures, and may cause developmental deformities. Due to its essential role in a toxicological profile and its relevance to human safety, knowledge regarding embryotoxicity is of great importance. Previous studies by this research group have shown that CdSâmaltodextrin QDs are biocompatible and nontoxic to cells and animals; however, QDs are able to induce embryotoxic effects. Therefore, as an effort to further address the issue, we studied the effects of CdSâmaltodextrin QDs on embryo and fetus development using an embryotoxicity and teratogenicity assay on chicken embryos. Chicken embryos exposed to CdSâmaltodextrin QDs (0.001, 0.01, 0.1 and 1â”g/kg) in ovo for 72âh showed growth and developmental alterations during the early stage and at the end of their development in a doseâdependent manner. Decreased development was observed during early stages (Stages 9/10 on the HamburgerâHamilton scale) when compared with untreated eggs (Stage 13). Chicken embryos exposed to lower CdSâmaltodextrin QDs doses (0.01, 0.1 and 1âng/kg) and incubated in ovo for 21âh also showed growth and development alterations during the early stages and at the end of their development in a doseâdependent manner. However, reduced development was observed at the end of the development period (21âdays), and this was associated with death of the chick. Current studies have also shown that CdSâdextrin induces embryotoxicity and teratogenicity, affecting mainly the CNS, the neural tube and somites in chicken embryos. The nature of the observed abnormalities suggests that these effects could be directly associated with nanoparticle concentrations affecting somitogenesis. Therefore, according to the results, there is a high probability that the prolonged accumulation of QDs in the maternal organism may be potentially harmful on embryo and fetus development. This study is limited to the analysis of embryotoxic and teratogenic effects induced by CdSâmaltodextrin QDs
Synthesis, characterization and biocompatibility of cadmium sulfide nanoparticles capped with dextrin for in vivo and in vitro imaging application
Soil macroinvertebrate communities: A world-wide assessment
© 2022 The Authors. Global Ecology and Biogeography published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.[Aim] Macroinvertebrates comprise a highly diverse set of taxa with great potential as indicators of soil quality. Communities were sampled at 3,694 sites distributed world-wide. We aimed to analyse the patterns of abundance, composition and network characteristics and their relationships to latitude, mean annual temperature and rainfall, land cover, soil texture and agricultural practices.[Location] Sites are distributed in 41 countries, ranging from 55° S to 57° N latitude, from 0 to 4,000 m in elevation, with annual rainfall ranging from 500 to >3,000 mm and mean temperatures of 5â32°C.[Time period] 1980â2018.[Major taxa studied] All soil macroinvertebrates: Haplotaxida; Coleoptera; Formicidae; Arachnida; Chilopoda; Diplopoda; Diptera; Isoptera; Isopoda; Homoptera; Hemiptera; Gastropoda; Blattaria; Orthoptera; Lepidoptera; Dermaptera; and âothersâ.[Methods] Standard ISO 23611-5 sampling protocol was applied at all sites. Data treatment used a set of multivariate analyses, principal components analysis (PCA) on macrofauna data transformed by Hellingerâs method, multiple correspondence analysis for environmental data (latitude, elevation, temperature and average annual rainfall, type of vegetation cover) transformed into discrete classes, coinertia analysis to compare these two data sets, and bias-corrected and accelerated bootstrap tests to evaluate the part of the variance of the macrofauna data attributable to each of the environmental factors. Network analysis was performed. Each pairwise association of taxonomic units was tested against a null model considering local and regional scales, in order to avoid spurious correlations.[Results] Communities were separated into five clusters reflecting their densities and taxonomic richness. They were significantly influenced by climatic conditions, soil texture and vegetation cover. Abundance and diversity, highest in tropical forests (1,895 ± 234 individuals/m2) and savannahs (1,796 ± 72 individuals/m2), progressively decreased in tropical cropping systems (tree-associated crops, 1,358 ± 120 individuals/m2; pastures, 1,178 ± 154 individuals/m2; and annual crops, 867 ± 62 individuals/m2), temperate grasslands (529 ± 60 individuals/m2), forests (232 ± 20 individuals/m2) and annual crops (231 ± 24 individuals/m2) and temperate dry forests and shrubs (195 ± 11 individuals/m2). Agricultural management decreased overall abundance by â€54% in tropical areas and 64% in temperate areas. Connectivity varied with taxa, with dominant positive connections in litter transformers and negative connections with ecosystem engineers and Arachnida. Connectivity and modularity were higher in communities with low abundance and taxonomic richness.[Main conclusions] Soil macroinvertebrate communities respond to climatic, soil and land-cover conditions. All taxa, except termites, are found everywhere, and communities from the five clusters cover a wide range of geographical and environmental conditions. Agricultural practices significantly decrease abundance, although the presence of tree components alleviates this effect.Peer reviewe
Innovación del Diseño para el Desarrollo Social
Una labor de sĂntesis alrededor de la gran temĂĄtica de este
libro que surge a partir de una serie de reflexiones y propuestas
encaminadas desde la innovación del diseño para
el desarrollo social, refleja una invitaciĂłn al lector para
enunciar a partir de su lectura nuevas discusiones sobre el
quehacer del diseño con una perspectiva de innovación
para este tipo de desarrollo, es pues este texto una invitaciĂłn
a enunciar nuevos retos y diĂĄlogos partiendo de reconocer
al desarrollo social como uno de los pilares fundamentales
desde la OrganizaciĂłn de las Naciones Unidas
(ONU) como parte fundamental para garantizar el mejoramiento
de la vida de las personas. Desde la disciplina del
diseño y retomado como eje para su discusiĂłn se pretenderĂa
establecer una serie de reflexiones y acciones que
permitan atender situaciones para grupos minoritarios y
vulnerables, asĂ como apoyar esfuerzos encaminados a
mejorar la calidad de vida de los integrantes de grupos y
sociedades establecidas y recuperar el patrimonio cultural
como parte fundamental de las identidades culturales y
por tanto de la historia de la humanidad.A lo largo de la historia, el diseño, en cualquiera de sus
manifestaciones, ha estado presente en todos los ĂĄmbitos.
Se ha convertido en una disciplina que evoluciona al ritmo
de las sociedades, que se pone al servicio de las necesidades
de mercado pero también de las que requieren un
abordaje distinto, observadas desde una mirada que concierne
a lo social, entendido Ă©ste como lo que se reproduce
o se instaura en el colectivo, en el grupo, en las comunidades,
en las sociedades como parte significativa de sus
cotidianeidades. El Diseño desde esta perspectiva acompaña
al ser humano produciendo una significaciĂłn de los
objetos como parte fundamental de sus vidas, que transforma
una realidad deseada en una realidad concreta, de
aquĂ la importancia de crear una conciencia social para la
praxis laboral de esta disciplina. En este sentido el campo
profesional, académico y de investigación del diseño debe
ocuparse de crear, difundir y divulgar el quehacer de la
misma, manifestando un equilibrio entre conciencia, racionalidad
y la realidad.
Desde el contexto planteado, la Universidad AutĂłnoma
del Estado de México, a través de su Facultad de Arquitectura
y Diseño presenta en esta obra una serie de reflexiones
en torno al papel que desempeña el diseño humanĂstico,
cientĂfico y tecnolĂłgico desde un enfoque de vanguardia
e innovaciĂłn para el desarrollo social, como resultado de la
experiencia vertida en el Coloquio Internacional de Diseño
que organiza éste año este espacio académico, en donde
cada una de las aportaciones refleja la experiencia de cada
uno de sus participantes; con base en ello, el presente libro
integrado por una compilaciĂłn de trabajos ofrece descripciones,
anĂĄlisis y propuestas que contribuyen a la soluciĂłn
de problemas procurando un desarrollo social
Diseño para el consumo cultural, la innovación y la inclusión social
Esta obra presenta diversos trabajos de investigaciĂłn que tienen en comĂșn propuestas de diseño desde la cultura, la inclusiĂłn y la innovaciĂłn social, desarrolladas por investigadores nacionales e internacionales adscritos a diversas universidades, asĂ como a programas de posgrado
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Abstract
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and lowâmiddle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of âsingle-useâ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for lowâmiddle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both highâ and lowâmiddleâincome countries
Synthesis, characterization and toxicological evaluation of maltodextrin capped cadmium sulfide nanoparticles in human cell lines and chicken embryos
Abstract Background Semiconductor Quantum dots (QDs) have become quite popular thanks to their properties and wide use in biological and biomedical studies. However, these same properties entail new challenges in understanding, predicting, and managing potential adverse health effects following exposure. Cadmium and selenium, which are the major components of the majority of quantum dots, are known to be acutely and chronically toxic to cells and organisms. Protecting the core of nanoparticles can, to some degree, control the toxicity related to cadmium and selenium leakage. Results This study successfully synthesized and characterized maltodextrin coated cadmium sulfide semiconductor nanoparticles. The results show that CdS-MD nanoparticles are cytotoxic and embryotoxic. CdS-MD nanoparticles in low concentrations (4.92 and 6.56 nM) lightly increased the number of HepG2 cell. A reduction in MDA-MB-231 cells was observed with concentrations higher than 4.92 nM in a dose response manner, while Caco-2 cells showed an important increase starting at 1.64 nM. CdS-MD nanoparticles induced cell death by apoptosis and necrosis in MDA-MD-231 cells starting at 8.20 nM concentrations in a dose response manner. The exposure of these cells to 11.48-14.76 nM of CdS-MD nanoparticles induced ROS production. The analysis of cell proliferation in MDA-MB-231 showed different effects. Low concentrations (1.64 nM) increased cell proliferation (6%) at 7 days (pâ4.92 nM) increased cell proliferation in a dose response manner (15-30%) at 7 days. Exposures of chicken embryos to CdS-MD nanoparticles resulted in a dose-dependent increase in anomalies that, starting at 9.84 nM, centered on the heart, central nervous system, placodes, neural tube and somites. No toxic alterations were observed with concentrations ofâ Conclusions Our results indicate that CdS-MD nanoparticles induce cell death and alter cell proliferation in human cell lines at concentrations higher than 4.92 nM. We also demonstrated that they are embryotoxic. However, no toxic effects were observed with doses lower than 3.28 nM in neither cells nor chicken embryos. The CdS-MD nanoparticles used in this study can be potentially used in bio-imaging applications. However, further studies using mammalian species are required in order to discard more toxic effects.</p