Shape-Dependent Complementary Ditopic Terpyridine Pair with Two Levels of Self-Recognition for Coordination-Driven Self-Assembly.

Molecular recognition in biological systems plays a vital role in the precise construction of biomacromolecules and the corresponding biological activities. Such recognition mainly relies on the highly specific binding of complementary molecular pairs with complementary sizes, shapes, and intermolecular forces. It still remains challenging to develop artificial complementary motif pairs for coordination-driven self-assembly. Herein, a series of shape-dependent complementary motif pairs, based on ditopic 2,2':6',2″-terpyridine (TPY) backbone, are designed and synthesized. The fidelity degrees of self-assemblies from these motifs are carefully evaluated by multi-dimensional mass spectrometry, nuclear magnetic resonance spectroscopy, and molecular modeling. In addition, two levels of self-recognition in both homoleptic and heteroleptic assembly are discovered in the assembled system. Through finely tuning the shape and size of the ligands, a complementary pair is developed with error-free narcissistically self-sorting at two levels of self-recognition, and the intrinsic principle is carefully investigated.

Enhanced Transport of Shape and Rigidity-Tuned α-Lactalbumin Nanotubes across Intestinal Mucus and Cellular Barriers.

Mucus is a viscoelastic biological hydrogel that protects the epithelial surface from penetration by most nanoparticles, which limits the efficiency of oral drug delivery. Pursuing highly efficient, biocompatible, and biodegradable oral drug vehicles is of central importance to the development of promising nanomedicine. Here, we prepared five peptosomes (PSs) with various sizes, shapes, and rigidities based on self-assembly of amphiphilic α-lactalbumin (α-lac) peptides from partial enzymolysis and cross-linking. The mucus permeation of α-lac PSs and release of curcumin (Cur) encapsulated in these PSs were evaluated. Compared with a long nanotube, big nanosphere, small nanosphere, and cross-linked short nanotube, we demonstrated that a short nanotube (SNT) exhibits excellent permeability in mucus, which enables it to arrive at epithelial cells quickly. Besides, SNT exhibits the highest cellular uptake and transmembrane permeability on Caco-2/HT29-MTX (E12) 3D coculture model. In vivo pharmacokinetic evaluation revealed that SNT formulation shows the highest curcumin bioavailability, which is 6.85-folds higher than free Cur. Most importantly, Cur loaded in SNT exhibits the optimum therapeutic efficacy for in vivo treatment of dextran sulfate sodium (DSS)-induced ulcerative colitis. In the end, the mechanism of the high permeability of SNTs through mucus was explained by coarse-grained molecular dynamics simulations, which indicated that short time scale jiggling and flying across pores of mucus network played key roles. These findings revealed the tubular α-lac PSs could be a promising oral drug delivery system targeted to mucosal for improving absorption and bioavailability of hydrophobic bioactive ingredients.

Amphiphilic Hybrid Dendritic-Linear Molecules as Nanocarriers for Shape-Dependent Antitumor Drug Delivery.

Nanoparticles based on hybrid block copolymers had been expected as effective nanocarriers for hydrophobic drug delivery. Herein, the novel dendritic-linear molecules from OEG dendron conjugated with octadecylamine (G2-C18) was designed, synthesized, and further applied as nanocarrier to prepare 10-hydroxycamptothecin (HCPT) nanoparticles via antisolvent precipitation method. It seemed that the feed weight ratio of HCPT vs G2-C18 not only affected the drug-loading content of nanoparticles but also influenced the morphology of HCPT nanoparticles; the morphology of HCPT nanoparticles was changed from nanosphere (NSs) to nanorod (NRs) with increasing the feed weight ratio. Both of HCPT nanoparticles presented good stability and similar drug release profiles, but different anticancer efficacy and cellular uptake mechanism. The cytotoxicity of HCPT NRs was enhanced significant comparing with HCPT NSs, the IC50 value was 2-fold lower than HCPT NSs ( p < 0.05). More importantly, HCPT NRs showed apparently higher antitumor activity in vivo, the inhibition rate of HCPT NRs was 1.3-fold higher than HCPT NSs. Based on these results, it suggested that the antitumor activity could be influenced significantly by particle morphology, which should be considered and optimized during the nanocarrier design.

Rotation-Facilitated Rapid Transport of Nanorods in Mucosal Tissues.

Mucus is a viscoelastic gel layer that typically protects exposed surfaces of the gastrointestinal (GI) tract, lung airways, and other mucosal tissues. Particles targeted to these tissues can be efficiently trapped and removed by mucus, thereby limiting the effectiveness of such drug delivery systems. In this study, we experimentally and theoretically demonstrated that cylindrical nanoparticles (NPs), such as mesoporous silica nanorods and calcium phosphate nanorods, have superior transport and trafficking capability in mucus compared with spheres of the same chemistry. The higher diffusivity of nanorods leads to deeper mucus penetration and a longer retention time in the GI tract than that of their spherical counterparts. Molecular simulations and stimulated emission of depletion (STED) microscopy revealed that this anomalous phenomenon can be attributed to the rotational dynamics of the NPs facilitated by the mucin fibers and the shear flow. These findings shed new light on the shape design of NP-based drug delivery systems targeted to mucosal and tumor sites that possess a fibrous structure/porous medium.

Simple Surfactant Concentration-Dependent Shape Control of Polyhedral Fe3 O4 Nanoparticles and Their Magnetic Properties.

The shape and size of monodisperse Fe3 O4 nanoparticles (NPs) are controlled using a chemical solution synthesis in the presence of the surfactant cetylpyridinium chloride (CPC). Cubic Fe3 O4 NPs surrounded by six {100} planes are obtained in the absence of CPC. Increasing the CPC content during synthesis causes the shape of the resulting Fe3 O4 NPs to change from cubic to truncated cubic, cuboctahedral, truncated octahedral, and finally octahedral. During this evolution, the predominantly exposed planes of the Fe3 O4 NPs vary from {100} to {111}. The shape control results from the synergistic effect of the pyridinium cations, chloride anions, and long-chain alkyl groups of CPC, which is confirmed by comparison with NPs synthesized in the presence of various related cationic surfactants. The size of the cubic Fe3 O4 NPs can be tuned from 50 to 200 nm, by changing the concentration of oleic acid in the reaction solution. The Fe3 O4 NPs exhibit shape-dependent saturation magnetization, remanent magnetization, and coercivity.

Antimicrobial activity of fluorescent Ag nanoparticles.

UNLABELLED: The antimicrobial activity of fluorescent Ag nanoparticles of 1·5 nm (nAg-Fs) is demonstrated and compared with the other Ag nanoparticles of different shapes and size. The antimicrobial activity was evaluated using Gram-positive (Staphylococcus epidermidis NCIM2493 and Bacillus megaterium) and Gram-negative bacteria (Pseudomonas aeruginosa ATCC27853 and Escherichia coli) and fungal strains (Candida albicans and Aspergillus niger). Insights into the possible mechanism were investigated using fluorescence microscope and cytoplasmic materials release assay. The fluorescence microscopic measurements show that the nAg-Fs are localized at the centre of the cell, and 50% decrease in the fluorescence intensity was observed upon 2-h incubation. Maximum cytoplasmic release was observed with spherical Ag nanoparticles of 10 nm. Although the nAg-F shows minimum cytoplasmic release, it has the highest activity. The microbial killing effect of nAg-Fs is actually originates from its intracellular activity. The antimicrobial activity of nAg-Fs is significantly higher than the other synthesized nanoparticles of different shapes and size. The activity of the nanoparticles has been rationalized by considering the shape, size and surface structure of the particles. SIGNIFICANCE AND IMPACT OF THE STUDY: This study aims to demonstrate the size and shape-dependent antimicrobial activity of Ag nanoparticles. It is shown for the first time that the fluorescent Ag nanoparticles of 1·5 nm have superior antimicrobial activity with respect to the larger particles. The shape and size of the particles actually control their activity. The smaller particles can easily penetrate the cell wall and have pronounced activity. These findings may be useful in the development of potential antimicrobial agents.

Shape-Regulated Motion and Energy Conversion of Polyelectrolyte Membrane Actuators.

Smart actuators hold great potential in soft robotics and sensors, but their movement at the fluid interface is less understood and controlled, hindering their performances and applications in complicated fluids. Here an ethanol-containing polyelectrolyte actuator is prepared that demonstrates excellent actuating performance via the Marangoni effect. These actuators exhibit enduring (17 min), repeatable (50 cycles), and autonomous motion on the water surface. More importantly, the motion of actuators are dependent on their shapes. Polygonal actuators with more edges exhibit round motion attached to walls of containers, while the actuators with few edges move randomly. On the basis of this property, the circular actuators can pass through pipe bends with S-shaped complex geometry. These unique advantages lend the actuators to successful applications in wireless sensing (standard 0-5 V level signals) for locating obstructions inside invisible pipes and continuous energy harvesting (7700 nC per cycle) for micro mechanical energy.

Shape-dependent synthesis and photocatalytic degradation by Cu2O nanocrystals: Kinetics and photocatalytic mechanism.

In this study, Cu2O crystals with different morphologies were synthesized to investigate the effect of exposed crystalline facets on photocatalytic degradation efficiency. By adjusting the addition amount of PVP, different morphologies of Cu2O crystals were obtained, such as cubic, decahedral, octahedral, etc. XRD, SEM, and TEM characterizations were used to observe the properties of the synthesized Cu2O in terms of morphology, size, and lattice structure. The results showed that the octahedral cuprous oxide had the strongest photocatalytic degradation effect (78.3%). The study also explored the connection between different crystalline facets and MO microstructure, and the effect of crystalline facet selectivity on the pre-absorption and photocatalytic degradation of MO. Density Functional Theory (DFT) calculations were used to investigate the connection between the energy level structure of different crystalline facets of Cu2O and its photocatalytic activity. Finally, based on the experimental analysis and theoretical calculation, a new charge separation model on crystalline surface was proposed.

SHAPE DEPENDENT MOTION INTERPOLANTS FOR PLANAR OBJECTS.

Kinematics is most commonly about the motion of unbounded spaces. This paper deals with the kinematics of bounded shapes in a plane. This paper studies the problem of motion interpolation of a planar object with its shape taken into consideration. It applies and extends a shape dependent distance measure between two positions in the context of motion interpolation. Instead of using a fixed reference frame, a shape-dependent inertia frame of reference is used for formulating the distance between positions of a rigid object in a plane. The resulting distance function is then decomposed in two orthogonal directions and is used to formulate an interpolating function for the distance functions in these two directions. This leads to a shape dependent interpolation of translational components of a planar motion. In difference to the original concept of Kazerounian and Rastegar that comes with a shape dependent measure of the angular motion, it is assumed in this paper that the angular motion is shape independent as the angular metric is dimensionless. The resulting distance measure is not only a combination of translation and rotation parameters but also depends on the area moments of inertia of the object. It derives the explicit expressions for decomposing the shape dependent distance in two orthogonal directions, which is then used to obtain shape dependent motion interpolants in these directions. The resulting interpolants have similarities to the well-known spherical linear interpolants widely used in computer graphics in that they are defined using sinusoidal functions instead of linear interpolation in Euclidean space. The path of the interpolating motion can be adjusted by different choice of shape parameters. Examples are provided to illustrate the effect of object shapes on the resulting interpolating motions.

Review on Natural, Incidental, Bioinspired, and Engineered Nanomaterials: History, Definitions, Classifications, Synthesis, Properties, Market, Toxicities, Risks, and Regulations.

Nanomaterials are becoming important materials in several fields and industries thanks to their very reduced size and shape-related features. Scientists think that nanoparticles and nanostructured materials originated during the Big Bang process from meteorites leading to the formation of the universe and Earth. Since 1990, the term nanotechnology became very popular due to advances in imaging technologies that paved the way to specific industrial applications. Currently, nanoparticles and nanostructured materials are synthesized on a large scale and are indispensable for many industries. This fact fosters and supports research in biochemistry, biophysics, and biochemical engineering applications. Recently, nanotechnology has been combined with other sciences to fabricate new forms of nanomaterials that could be used, for instance, for diagnostic tools, drug delivery systems, energy generation/storage, environmental remediation as well as agriculture and food processing. In contrast with traditional materials, specific features can be integrated into nanoparticles, nanostructures, and nanosystems by simply modifying their scale, shape, and composition. This article first summarizes the history of nanomaterials and nanotechnology. Followed by the progress that led to improved synthesis processes to produce different nanoparticles and nanostructures characterized by specific features. The content finally presents various origins and sources of nanomaterials, synthesis strategies, their toxicity, risks, regulations, and self-aggregation.

Ray Optics for Gliders.

Control of self-propelled particles is central to the development of many microrobotic technologies, from dynamically reconfigurable materials to advanced lab-on-a-chip systems. However, there are few physical principles by which particle trajectories can be specified and can be used to generate a wide range of behaviors. Within the field of ray optics, a single principle for controlling the trajectory of light─Snell's law─yields an intuitive framework for engineering a broad range of devices, from microscopes to cameras and telescopes. Here we show that the motion of self-propelled particles gliding across a resistance discontinuity is governed by a variant of Snell's law, and develop a corresponding ray optics for gliders. Just as the ratio of refractive indexes sets the path of a light ray, the ratio of resistance coefficients is shown to determine the trajectories of gliders. The magnitude of refraction depends on the glider's shape, in particular its aspect ratio, which serves as an analogue to the wavelength of light. This enables the demixing of a polymorphic, many-shaped, beam of gliders into distinct monomorphic, single-shaped, beams through a friction prism. In turn, beams of monomorphic gliders can be focused by spherical and gradient friction lenses. Alternatively, the critical angle for total internal reflection can be used to create shape-selective glider traps. Overall our work suggests that furthering the analogy between light and microscopic gliders may be used for sorting, concentrating, and analyzing self-propelled particles.

Shape dependence of the release rate of chemicals from plastic microparticles.

The release of chemical additives from plastic microparticles in the aqueous phase represents a potential indirect threat for environment and biota. The estimate of the release timescale is demanded for drawing sensible conclusions on quantitative grounds. While the microparticles are generally taken to be spherical for ease of modelling, in reality the variety of shapes is large. Here, we face the problem of working out an empirical simple expression for estimating the release times for arbitrary shapes, assuming that the plastic material is in the rubbery state, that the dynamics inside the particle is a diffusion process, and that the release is irreversible. Our inspection is based on numerical simulations of the release process for randomly generated instances of regular and irregular geometries. The expression that we obtain allows one to estimate the release time in terms of the corresponding time (easy to compute) for the equal-volume spherical particle taken as reference, and of the ratio between the surface areas of particle and equivalent sphere.

A new model for settling velocity of non-spherical particles.

The settlement of non-spherical particles, such as propagules of plants and natural sediments, is commonly observed in riverine ecosystems. The settling process is influenced by both particle properties (size, density, and shape) and fluid properties (density and viscosity). Therefore, the drag law of non-spherical particles is a function of both particle Reynolds number and particle shape. Herein, a total of 828 settling data are collected from the literatures, which cover a wide range of particle Reynolds number (0.008-10000). To characterize the influence of particle shapes, sphericity is adopted as the general shape factor, which varies from 0.421 to 1.0. By comparing the measured drag with the standard drag curve of spheres, we modify the spherical drag law with three shape-dependent functions to develop a new drag law for non-spherical particles. Combined with an iterative procedure, a new model is thus obtained to predict the settling velocity of non-spherical particles of various shapes and materials. Further applications in hydrochorous propagule dispersal and sediment transport are projected based on deeper understanding of the settling process.

Shape-dependent significant physical mutilation and antibacterial mechanisms of gold nanoparticles against foodborne bacterial pathogens (Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus) at lower concentrations.

Gold nanoparticles (AuNPs) have been reported for their most desirable properties as compared to any other noble metal-based nanoparticles, which wider their applications in various fields including catalysis, bio-imaging, biosensors, medicine, biology, and material chemistry. In this study, the shape-dependent antibacterial activity of AuNPs: nanospheres (AuNSps), nanostars (AuNSts), and nanocubes (AuNCs) were investigated against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus at lower concentrations. The optical, crystallographic and morphological characterization of AuNPs was analyzed by UV-visible spectroscopy, X-ray diffraction spectroscopy, and transmission electron microscopy (TEM). Shape-dependent antibacterial qualitative and quantitative analyses revealed an effective bactericidal activity of AuNCs against the tested bacteria, followed by AuNSps and AuNSts. The study revealed that the AuNCs are effective bactericidal agents with 100% inactivation rate. The visual analysis confirmed the antibacterial activity of AuNCs and AuNSps by showing physical mutilated bacterial cells which involved cell loss, loosening of the cell wall, loss of flagella and cellular matrix. Finally, released nucleic acid was measured for the treated bacterial cells which support the physical mutilation by releasing 38 µg/mL (Pseudomonas aeruginosa) of cellular material after treating with AuNCs. It is concluded from this study that AuNPs showed the significant antibacterial property at lower concentrations. More applications can be explored including anti-infections, decontamination, and food safety.

Mechanistic study on antibacterial action of zinc oxide nanoparticles synthesized using green route.

A large array of diseases caused by bacterial pathogens and origination of multidrug resistance in their gene provokes the need of developing new vectors or novel drug molecules for effective drug delivery and thus, better treatment of disease. The nanoparticle has emerged as a novel drug molecule in last decade and has been used in various industrial fields like cosmetics, healthcare, agricultural, pharmaceuticals due to their high optical, electronic, medicinal properties. Use of nanoparticles as an antibacterial agent remain in current studies with metal nanoparticles like silver, gold, copper, iron and metal oxide nanoparticles like zinc oxide, copper oxide, titanium oxide and iron oxide nanoparticles. The high anti-bacterial activity of nanoparticles is due to their large surface area to volume ratio which allows binding of a large number of ligands on nanoparticle surface and hence, its complexation with receptors present on the bacterial surface. Green synthesis of Zinc Oxide Nanoparticle (ZnO NP) and its anti-bacterial application has been particularly discussed in the review literature. The present study highlights differential nanoparticle attachment to gram + and gram - bacterial surface and different mechanism adopted by nanoparticle for bacterial control. Pharmacokinetics and applications of ZnO NP are also discussed briefly.

Shape-Dependent Motion of Structured Photoactive Microswimmers.

We investigate the dynamics of structured photoactive microswimmers and show that morphology sensitively determines the swimming behavior. Particular to this study, a major portion of the light-activated particles' underlying structure is built from a photocatalytic material, made possible by dynamic physical vapor deposition (DPVD). We find that swimmers of this type exhibit unique shape-dependent autonomous swimming that is distinct from what is seen in systems with similar structural morphology but not fabricated directly from the catalyst. Notably, the direction of motion is a function of these parameters. Because the swimming behavior is strongly correlated with particle shape and material composition, DPVD allows for engineering small-scale propulsion by adjusting the fabrication parameters to match the desired performance.

Shape-Dependent Radiosensitization Effect of Gold Nanostructures in Cancer Radiotherapy: Comparison of Gold Nanoparticles, Nanospikes, and Nanorods.

The shape effect of gold (Au) nanomaterials on the efficiency of cancer radiotherapy has not been fully elucidated. To address this issue, Au nanomaterials with different shapes but similar average size (∼50 nm) including spherical gold nanoparticles (GNPs), gold nanospikes (GNSs), and gold nanorods (GNRs) were synthesized and functionalized with poly(ethylene glycol) (PEG) molecules. Although all of these Au nanostructures were coated with the same PEG molecules, their cellular uptake behavior differed significantly. The GNPs showed the highest cellular responses as compared to the GNSs and the GNRs (based on the same gold mass) after incubation with KB cancer cells for 24 h. The cellular uptake in cells increased in the order of GNPs > GNSs > GNRs. Our comparative studies indicated that all of these PEGylated Au nanostructures could induce enhanced cancer cell-killing rates more or less upon X-ray irradiation. The sensitization enhancement ratios (SERs) calculated by a multitarget single-hit model were 1.62, 1.37, and 1.21 corresponding to the treatments of GNPs, GNSs, and GNRs, respectively, demonstrating that the GNPs showed a higher anticancer efficiency than both GNSs and GNRs upon X-ray irradiation. Almost the same values were obtained by dividing the SERs of the three types of Au nanomaterials by their corresponding cellular uptake amounts, indicating that the higher SER of GNPs was due to their much higher cellular uptake efficiency. The above results indicated that the radiation enhancement effects were determined by the amount of the internalized gold atoms. Therefore, to achieve a strong radiosensitization effect in cancer radiotherapy, it is necessary to use Au-based nanomaterials with a high cellular internalization. Further studies on the radiosensitization mechanisms demonstrated that ROS generation and cell cycle redistribution induced by Au nanostructures played essential roles in enhancing radiosensitization. Taken together, our results indicated that the shape of Au-based nanomaterials had a significant influence on cancer radiotherapy. The present work may provide important guidance for the design and use of Au nanostructures in cancer radiotherapy.

Modelización del tiempo que tarda un paciente con cáncer diferenciado de tiroides en presentar la primera recaída / Modeling of the Time it Takes for a Patient with Differentiated Thyroid Cancer to Present the First Relapse / Modelagem do tempo que um paciente com câncer diferenciado de tireoide leva para apresentar a primeira recidiva

Introducción: de todos los carcinomas de tiroides, los diferenciados son los predominantes. Según la Asociación Colombiana de Endocrinología, la tasa de recaída puede ser de hasta del 30 %, especialmente en pacientes mayores de 45 años y con características tumorales agresivas. En esta investigación se estimó el tiempo libre de enfermedad que transcurre entre la finalización del tratamiento y la ocurren-cia de la primera recaída. Materiales y métodos: se tomó un archivo de datos con los registros de 469 pacientes con cáncer diferenciado de tiroides (cdt) tratados en una clínica especializada de cuarto nivel de complejidad en Bogotá (Colombia). Los datos se recolectaron entre enero de 1997 y diciembre de 2012 y se analizaron estadísticamente usando modelos paramétricos y no paramétricos para obtener las curvas de supervivencia y riesgo. Resultados: con el método no paramétrico se evidenció que en 8.5 años el 75 % de los pacientes no habrán presentado la primera recaída en cdt; mientras que en el método paramétrico el 50 % de los pacientes que no presentaron una tiroglobulina postratamiento menor o igual a 1 ng/mL y un tamaño del tumor menor o igual a 2 cm, su tiempo estimado de la primera recaída fue 29.2 años. Conclusiones: el tiempo libre de enfermedad y el riesgo de hacer recaída para pacientes con cdt está afectado por la presencia de un tamaño de tumor mayor a 2 cm en el momento de la consulta y una cantidad de tiroglobulina mayor a 1 ng/mL, registrada al terminar el tratamiento.

Introduction: Between all thyroid carcinomas, the differentiated are predominant. According to the Colombian Association of Endocrinology, the relapse rate can be up to 30%, especially in patients older than 45 years old and with aggressive tumor characteristics. In this investigation, the time that elapses between the initial surgical treatment and the first relapse of the disease was estimated. Materials and methods: A data file was taken with the records of 469 patients with differentiated thyroid cancer (cdt) treated in a specialized clinic of fourth level of complexity iv in the city of Bogotá (Colombia). Data were collected between January 1997 and December 2012 and were statistically analyzed using para-metric and non-parametric models to obtain survival curves and risk. Results: With the non-parametric method, it is evident that in 8.5 years 75% of the patients will not have presented the first relapse in cdt. While applying the parametric method 50% of patients who do not have a postreatment thyroglobulin or one less than or equal to 1 ng/mL and a tumour size less than or equal to 2 cm, their estimated time of First relapse was 29.2 years. Conclusions: Disease-free time and the risk of relapse for patients with cdt is affected by the presence of a tumor size greater than 2 cm at the time of consultation and levels of thyroglobulin greater than 1 ng/mL, recorded at the end of the treatment.

Introdução: de todos os carcinomas da tireoide, os diferenciados são os predominantes. Segundo a Associação Colombiana de Endocrinologia, a taxa de recaída pode ser até 30%, principalmente em pacien-tes com mais de 45 anos e com características de agressividade tumoral. Nesta investigação, estimou-se o tempo decorrido entre o tratamento cirúrgico inicial e a primeira recaída. Materiais e métodos: tomou-se um arquivo de dados com os prontuários de 469 pacientes com câncer diferenciado de tireoide (cdt) atendidos em uma clínica especializada de quarto nível de complexidade na cidade de Bogotá (Colombia). Coletaram-se os dados entre janeiro de 1997 e dezembro de 2012, que depois foram analisados estatisti-camente usando modelos paramétricos e não paramétricos para encontrar curvas de sobrevida e risco. Resultados: com o método não paramétrico, evidenciou-se que, em 8,5 anos, 75% dos pacientes não terão apresentado a primeira recaída na cdt. Enquanto na aplicação do método paramétrico, 50% dos pacientes que não apresentaram tireoglobulina pós-tratamento ou valores menores ou iguais a 1 ng/mL e tamanho do tumor menor ou igual a 2 cm, seu tempo estimado de primeira recaída foi de 29,2 anos. Conclusões: o tempo livre de doença e o risco de recaída, para pacientes com cdt são afetados pela presença de tama-nho de tumor maior a 2 cm no momento da consulta e uma quantidade de tireoglobulina maior a 1 ng/mL, registrada ao terminar o tratamento.

Macrophage uptake of cylindrical microparticles investigated with correlative microscopy.

Cylindrical particles offer the opportunity to develop controlled and sustained release systems for the respiratory tract. One reason is that macrophages can phagocyte such particles only from either of the two ends. We investigated the uptake behaviour of murine alveolar macrophages incubated with elongated submicron-structured particles. For that purpose, fluorescent model silica nanoparticles were interconnected with the biocompatible polysaccharide agarose, building up cylindrical particles within the pores of track-etched membranes. In contrast to common approaches we determined the uptake at different time points with scanning electron microscopy, fluorescence microscopy, and the combination of both techniques - correlative microscopy (CLEM). As a consequence, we could securely identify uptake events and observe in detail the engulfment of particles and confirm, that phagocytosis could only be observed from the tips of the cylinders. CLEM allowed a comparison of the uptake measured with different techniques at identical macrophages. Qualitative and quantitative evaluation of this cylindrical particle uptake showed substantial differences between fluorescence microscopy, electron microscopy and the combination of both (CLEM) within 24h.