1,721,260 research outputs found
Interactions of Engineered Nanoparticles with Organs Protected by Internal Biological Barriers
Full text linkEngineered nanomaterials may exert adverse effects on human health which, in turn, may be linked
to their propensity to cross biological barriers in the body. Here, we will discuss available evidence
based on in vivo studies for interactions of commercially relevant nanoparticles with critical internal
barriers. The internal barriers at focus of this review are the blood-brain barrier (BBB), protecting
the brain, the blood-testis barrier (BTB), protecting the male germ line, and the placenta, protecting
the developing fetus. The route of exposure (pulmonary, gastrointestinal, intravenous,
intraperitoneal, dermal), and the portal of entry of nanoparticles into the body, is of critical
importance. Different physico-chemical properties, not only size, may determine the ability of
nanoparticles to breach biological barriers; the situation is further compounded by the formation of
a so-called corona of biomolecules on the surface of nanoparticles, the composition of which may
vary depending on the route of exposure and the “history” of the nanoparticles as they translocate
from one biological compartment to another. The relevance of nanoparticle interactions with
internal biological barriers for their impact on the organs protected by these barriers is discussed
Graphene and the Immune System: A Romance of Many Dimensions
Full text linkGraphene-based materials (GBMs) are emerging as attractive materials for biomedical applications. Understanding how these materials are perceived by and interact with the immune system is of fundamental importance. Phagocytosis is a major mechanism deployed by the immune system to remove pathogens, particles, and cellular debris. Here, we discuss recent studies on the interactions of GBMs with different phagocytic cells, including macrophages, neutrophils, and dendritic cells. The importance of assessing GBMs for endotoxin contamination is discussed as this may skew results. We also explore the role of the bio-corona for interactions of GBMs with immune cells. Finally, we highlight recent evidence for direct plasma membrane interactions of GBMs
Adverse effects of engineered nanomaterials
No full textAn essential reference that discusses occupational exposure and the adverse health effects of engineered nano materials and highlights current and future biomedical applications of these nano materials in relation to nano safety. Multi-authored book written by leading US andEuropean experts on nanotoxicology and nanomedicine. Discusses the health implications and a clinical translation of experimental data in this area. Takes a schematic, non-exhaustive approach to summarize the most important research data in this field includes a glossary, with a brief explanation of the term and with reference to where the phrase or term has been used will be included in the book
Nano-bio interactions: a neutrophil-centric view
Full text linkNeutrophils are key components of the innate arm of the immune system and represent the frontline of host defense against intruding pathogens. However, neutrophils can also cause damage to the host. Nanomaterials are being developed for a multitude of different purposes and these minute materials may find their way into the body through deliberate or inadvertent exposure; understanding nanomaterial interactions with the immune system is therefore of critical importance. However, whereas numerous studies have focused on macrophages, less attention is devoted to nanomaterial interactions with neutrophils, the most abundant leukocytes in the blood. We discuss the impact of engineered nanomaterials on neutrophils and how neutrophils, in turn, may digest certain carbon-based materials such as carbon nanotubes and graphene oxide. We also discuss the role of the corona of proteins adsorbed onto the surface of nanomaterials and whether nanomaterials are sensed as pathogens by cells of the immune system
Mechanisms of carbon nanotube-induced toxicity: Focus on oxidative stress
Full text linkNanotechnologies are emerging as highly promising technologies in many sectors in the society. However, the increasing use of engineered nanomaterials also raises concerns about inadvertent exposure to these materials and the potential for adverse effects on human health and the environment. Despite several years of intensive investigations, a common paradigm for the understanding of nanoparticle-induced toxicity remains to be firmly established. Here, the so-called oxidative stress paradigm is scrutinized. Does oxidative stress represent a secondary event resulting inevitably from disruption of biochemical processes and the demise of the cell, or a specific, non-random event that plays a role in the induction of cellular damage e.g. apoptosis? The answer to this question will have important ramifications for the development of strategies for mitigation of adverse effects of nanoparticles. Recent examples of global lipidomics studies of nanoparticle-induced tissue damage are discussed along with proteomics and transcriptomics approaches to achieve a comprehensive understanding of the complex and interrelated molecular changes in cells and tissues exposed to nanoparticles. We also discuss instances of non-oxidative stress-mediated cellular damage resulting from direct physical interference of nanomaterials with cellular structures
Nanodrugs to target articular cartilage: An emerging platform for osteoarthritis therapy
No full textCartilage undergoes drastic structural changes during the development of osteoarthritis and cannot heal itself due to a defective chondrocyte response. Thus, much effort has been invested in the development of disease modifying drugs able to block key mediators within the cartilage matrix and biochemical pathways inside chondrocytes. However, the delivery of therapeutic agents into cartilage is ineffective. This has led to the use of cartilage-targeted nanodrugs to accumulate therapeutic agents into specific cartilage sub-compartments. This review will describe the nanodrugs targeted to specific components of cartilage matrix to generate drug reservoirs within the cartilage. The nanodrugs used as chondrocyte-specific gene delivery systems are also described. Although the use of cartilage-targeted nanodrugs in osteoarthritis is still in its infancy, these studies lay the foundation for the development of novel approaches for preventing the progression of cartilage breakdown and improving the quality of life of patients with osteoarthritis
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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