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1.
Nat Commun ; 15(1): 2852, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605028

RESUMO

Voids-the nothingness-broadly exist within nanomaterials and impact properties ranging from catalysis to mechanical response. However, understanding nanovoids is challenging due to lack of imaging methods with the needed penetration depth and spatial resolution. Here, we integrate electron tomography, morphometry, graph theory and coarse-grained molecular dynamics simulation to study the formation of interconnected nanovoids in polymer films and their impacts on permeance and nanomechanical behaviour. Using polyamide membranes for molecular separation as a representative system, three-dimensional electron tomography at nanometre resolution reveals nanovoid formation from coalescence of oligomers, supported by coarse-grained molecular dynamics simulations. Void analysis provides otherwise inaccessible inputs for accurate fittings of methanol permeance for polyamide membranes. Three-dimensional structural graphs accounting for the tortuous nanovoids within, measure higher apparent moduli with polyamide membranes of higher graph rigidity. Our study elucidates the significance of nanovoids beyond the nothingness, impacting the synthesis‒morphology‒function relationships of complex nanomaterials.

2.
Sci Adv ; 10(16): eadk0217, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38630809

RESUMO

Biological phenomena, from enzymatic catalysis to synaptic transmission, originate in the structural transformations of biomolecules and biomolecular assemblies in liquid water. However, directly imaging these nanoscopic dynamics without probes or labels has been a fundamental methodological challenge. Here, we developed an approach for "electron videography"-combining liquid phase electron microscopy with molecular modeling-with which we filmed the nanoscale structural fluctuations of individual, suspended, and unlabeled membrane protein nanodiscs in liquid. Systematic comparisons with biochemical data and simulation indicate the graphene encapsulation involved can afford sufficiently reduced effects of the illuminating electron beam for these observations to yield quantitative fingerprints of nanoscale lipid-protein interactions. Our results suggest that lipid-protein interactions delineate dynamically modified membrane domains across unexpectedly long ranges. Moreover, they contribute to the molecular mechanics of the nanodisc as a whole in a manner specific to the protein within. Overall, this work illustrates an experimental approach to film, quantify, and understand biomolecular dynamics at the nanometer scale.


Assuntos
Elétrons , Nanoestruturas , Proteínas de Membrana/química , Simulação de Dinâmica Molecular , Microscopia Eletrônica , Lipídeos/química , Bicamadas Lipídicas/química , Nanoestruturas/química
3.
Adv Mater ; 36(15): e2308720, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38189549

RESUMO

Template-directed self-assembly of solidifying eutectics results in emergence of unique microstructures due to diffusion constraints and thermal gradients imposed by the template. Here, the importance of selecting the template material based on its conductivity to control heat transfer between the template and the solidifying eutectic, and thus the thermal gradients near the solidification front, is demonstrated. Simulations elucidate the relationship between the thermal properties of the eutectic and template and the resultant microstructure. The overarching finding is that templates with low thermal conductivities are generally advantageous for forming highly organized microstructures. When electrochemically porosified silicon pillars (thermal conductivity < 0.3 Wm-1K-1) are used as the template into which an AgCl-KCl eutectic is solidified, 99% of the unit cells in the solidified structure exhibit the same pattern. In contrast, when higher thermal conductivity crystalline silicon pillars (≈100 Wm-1K-1) are utilized, the expected pattern is only present in 50% of the unit cells. The thermally engineered template results in mesostructures with tunable optical properties and reflectances nearly identical to the simulated reflectances of perfect structures, indicating highly ordered patterns are formed over large areas. This work highlights the importance of controlling heat flows in template-directed self-assembly of eutectics.

4.
J Sport Rehabil ; 33(1): 49-52, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37758261

RESUMO

CLINICAL SCENARIO: Exercise-associated muscle cramps (EAMC) are sudden, painful, and involuntary contractions of skeletal muscles during or after physical activity. The best treatment for EAMC is gentle static stretching until abatement. Stretching is theorized to relieve EAMC by normalizing alpha motor neuron control, specifically by increasing Golgi tendon organ activity, and physically separating contractile proteins. However, it is unclear if stretching or flexibility training prevents EAMC via the same mechanisms. Despite this, many clinicians believe prophylactic stretching prevents EAMC occurrence. CLINICAL QUESTION: Do athletes who experience EAMC during athletic activities perform less prophylactic stretching or flexibility training than athletes who do not develop EAMC during competitions? SUMMARY OF KEY FINDINGS: In 3 cohort studies and 1 case-control study, greater preevent muscle flexibility, stretching, or flexibility training (ie, duration, frequency) was not predictive of who developed EAMC during competition. In one study, athletes who developed EAMC actually stretched more often and 9 times longer (9.8 [23.8] min/wk) than noncrampers (1.1 [2.5] min/wk). CLINICAL BOTTOM LINE: There is minimal evidence that the frequency or duration of prophylactic stretching or flexibility training predicts which athletes developed EAMC during competition. To more effectively prevent EAMC, clinicians should identify athletes' unique intrinsic and extrinsic risk factors and target those risk factors with interventions. STRENGTH OF RECOMMENDATION: Minimal evidence from 3 prospective cohort studies and 1 case-control study (mostly level 3 studies) that suggests prophylactic stretching or flexibility training can predict which athletes develop EAMC during athletic competitions.


Assuntos
Cãibra Muscular , Exercícios de Alongamento Muscular , Humanos , Cãibra Muscular/etiologia , Cãibra Muscular/prevenção & controle , Cãibra Muscular/epidemiologia , Estudos Prospectivos , Estudos de Casos e Controles , Músculo Esquelético
5.
Eur J Cancer ; 184: 48-59, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36898233

RESUMO

BACKGROUND: ExteNET showed that neratinib, an irreversible pan-HER tyrosine kinase inhibitor, given for 1 year after trastuzumab-based therapy significantly improved invasive disease-free survival in women with early-stage HER2-positive breast cancer. We report the final analysis of overall survival in ExteNET. METHODS: In this international, randomised, double-blind, placebo-controlled, phase 3 trial, women aged 18 years or older with stage 1-3c (amended to stage 2-3c) HER2-positive breast cancer who had completed neoadjuvant and adjuvant chemotherapy plus trastuzumab were eligible. Patients were randomly assigned to oral neratinib 240 mg/day or placebo for 1 year. Randomisation was stratified according to hormone receptor (HR) status (HR-positive vs. HR-negative), nodal status (0, 1-3 or 4+), and trastuzumab regimen (sequentially vs. concurrently with chemotherapy). Overall survival was analysed by intention to treat. ExteNET is registered (Clinicaltrials.gov: NCT00878709) and is complete. RESULTS: Between July 9, 2009, and October 24, 2011, 2840 women received neratinib (n = 1420) or placebo (n = 1420). After a median follow-up of 8.1 (IQR, 7.0-8.8) years, 127 patients (8.9%) in the neratinib group and 137 patients (9.6%) in the placebo group in the intention-to-treat population had died. Eight-year overall survival rates were 90.1% (95% CI 88.3-91.6) with neratinib and 90.2% (95% CI 88.4-91.7) with placebo (stratified hazard ratio 0.95; 95% CI 0.75-1.21; p = 0.6914). CONCLUSIONS: Overall survival in the extended adjuvant setting was comparable for neratinib and placebo after a median follow-up of 8.1 years in women with early-stage HER2-positive breast cancer.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Intervalo Livre de Doença , Método Duplo-Cego , Receptor ErbB-2 , Trastuzumab/efeitos adversos
6.
Sci Adv ; 8(8): eabk1888, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35196079

RESUMO

Biological morphogenesis has inspired many efficient strategies to diversify material structure and functionality using a fixed set of components. However, implementation of morphogenesis concepts to design soft nanomaterials is underexplored. Here, we study nanomorphogenesis in the form of the three-dimensional (3D) crumpling of polyamide membranes used for commercial molecular separation, through an unprecedented integration of electron tomography, reaction-diffusion theory, machine learning (ML), and liquid-phase atomic force microscopy. 3D tomograms show that the spatial arrangement of crumples scales with monomer concentrations in a form quantitatively consistent with a Turing instability. Membrane microenvironments quantified from the nanomorphologies of crumples are combined with the Spiegler-Kedem model to accurately predict methanol permeance. ML classifies vastly heterogeneous crumples into just four morphology groups, exhibiting distinct mechanical properties. Our work forges quantitative links between synthesis and performance in polymer thin films, which can be applicable to diverse soft nanomaterials.

7.
Ecol Appl ; 32(2): e2500, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34800082

RESUMO

Near-term iterative forecasting is a powerful tool for ecological decision support and has the potential to transform our understanding of ecological predictability. However, to this point, there has been no cross-ecosystem analysis of near-term ecological forecasts, making it difficult to synthesize diverse research efforts and prioritize future developments for this emerging field. In this study, we analyzed 178 near-term (≤10-yr forecast horizon) ecological forecasting papers to understand the development and current state of near-term ecological forecasting literature and to compare forecast accuracy across scales and variables. Our results indicated that near-term ecological forecasting is widespread and growing: forecasts have been produced for sites on all seven continents and the rate of forecast publication is increasing over time. As forecast production has accelerated, some best practices have been proposed and application of these best practices is increasing. In particular, data publication, forecast archiving, and workflow automation have all increased significantly over time. However, adoption of proposed best practices remains low overall: for example, despite the fact that uncertainty is often cited as an essential component of an ecological forecast, only 45% of papers included uncertainty in their forecast outputs. As the use of these proposed best practices increases, near-term ecological forecasting has the potential to make significant contributions to our understanding of forecastability across scales and variables. In this study, we found that forecastability (defined here as realized forecast accuracy) decreased in predictable patterns over 1-7 d forecast horizons. Variables that were closely related (i.e., chlorophyll and phytoplankton) displayed very similar trends in forecastability, while more distantly related variables (i.e., pollen and evapotranspiration) exhibited significantly different patterns. Increasing use of proposed best practices in ecological forecasting will allow us to examine the forecastability of additional variables and timescales in the future, providing a robust analysis of the fundamental predictability of ecological variables.


Assuntos
Ecossistema , Previsões , Clorofila , Fitoplâncton/crescimento & desenvolvimento , Transpiração Vegetal , Pólen , Incerteza
8.
NPJ Breast Cancer ; 7(1): 77, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34117261

RESUMO

Circulating tumor cells (CTC) are prognostic in metastatic breast cancer (MBC). The CTC-endocrine therapy index (CTC-ETI), consisting of CTC-ER (estrogen receptor), BCL2, human epidermal growth factor receptor (HER2), and Ki67 expression, might predict resistance to endocrine therapy (ET) in patients with ER-positive MBC. One hundred twenty-one patients with ER-positive/HER2-negative MBC initiating a new ET after ≥1 lines of ET were enrolled in a prospective, multi-institutional clinical trial. CTC-ETI and clinical/imaging follow-up were performed at baseline and serial time points. Progression-free survival (PFS) and rapid progression (RP; determined at the 3-month time point) were primary endpoints. Associations with clinical outcomes used logrank and Fisher's exact tests. At baseline, 36% (38/107) of patients had ≥5 CTC/7.5 ml whole blood (WB). Patients with ≥5 vs. <5 CTC/7.5 ml WB had significantly worse PFS (median 3.3 vs. 5.9 months, P = 0.03). Elevated CTC at 1 month was associated with even worse PFS (1.9 vs. 5.0 months from the 1-month sample, P < 0.001). Low, intermediate, and high CTC-ETI were observed in 71 (66%), 8 (8%), and 28 (26%) patients, with median PFS of 6.9, 8.5, and 2.8 months, respectively (P = 0.008). Patients with high vs. low CTC and CTC-ETI more frequently experienced RP (CTC: 66% vs. 41%; P = 0.03; CTC-ETI: 79% vs. 40%; P = 0.002). In conclusion, CTC enumeration and the CTC-ETI assay are prognostic at baseline and follow-up in patients with ER-positive/HER2-negative MBC starting new ET. CTC at first follow-up might identify a group of patients with ER-positive MBC that could forego ET, but CTC-ETI did not contribute further.

9.
J Mater Chem B ; 8(37): 8490-8506, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32830213

RESUMO

The ongoing development of liquid-phase electron microscopy methods-in which specimens are kept fully solvated in the microscope by encapsulation in transparent, vacuum-tight chambers-is making it possible to investigate a wide variety of nanoscopic dynamic phenomena at the single-particle level, and with nanometer to atomic resolution. As such, there has been growing motivation to make liquid-phase electron microscopy tools applicable not only to inorganic materials, like metals, semiconductors, and ceramics, but also to "soft" materials such as biomolecules and cells, whose nanoscale dynamics and organization are intricately tied to their functionality. Here we review efforts toward making this an experimental reality, summarizing recent liquid-phase electron microscopy studies of whole cells, assembling peptides, and even individual proteins. Successes and challenges are discussed, as well as strategies to maximize the amount of accessible information and minimize the impact of the electron beam. We conclude with an outlook on the potential of liquid-phase electron microscopy to provide new insight into the rich and functional dynamics occurring in biological systems at the microscopic to molecular level.


Assuntos
Células/ultraestrutura , DNA/química , Microscopia Eletrônica/métodos , Proteínas/química , Vírion/química , Animais , Bactérias/química , Fungos/química , Humanos , Vírus/química
10.
ACS Appl Nano Mater ; 3(2): 937-945, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32149271

RESUMO

The assembly of proteins into amyloid fibrils has become linked not only with the progression of myriad human diseases, but also important biological functions. Understanding and controlling the formation, structure, and stability of amyloid fibrils is therefore a major scientific goal. Here we utilize electron microscopy-based approaches combined with quantitative statistical analysis to show how recently developed kind of amyloid modulators-multivalent polymer-peptide conjugates (mPPCs)-can be applied to control the structure and stability of amyloid fibrils. In doing so, we demonstrate that mPPCs are able to convert 40-residue amyloid beta fibrils into ordered nanostructures through a combination of fragmentation and bundling. Fragmentation is shown to be consistent with a model where the rate constant of fibril breakage is independent of the fibril length, suggesting a local and specific interaction between fibrils and mPPCs. Subsequent bundling, which was previously not observed, leads to the formation of sheet-like nanostructures which are surprisingly much more uniform than the starting fibrils. These nanostructures have dimensions independent of the molecular weight of the mPPC and retain the molecular-level ordering of the starting amyloid fibrils. Collectively, we reveal quantitative and nanoscopic understanding of how mPPCs can be applied to control amyloid structure and stability, and demonstrate approaches to elucidate nanoscale amyloid phase behavior in the presence of functional macromolecules and other modulators.

11.
PeerJ ; 7: e7057, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31249734

RESUMO

The observed dynamics of infectious diseases are driven by processes across multiple scales. Here we focus on two: within-host, that is, how an infection progresses inside a single individual (for instance viral and immune dynamics), and between-host, that is, how the infection is transmitted between multiple individuals of a host population. The dynamics of each of these may be influenced by the other, particularly across evolutionary time. Thus understanding each of these scales, and the links between them, is necessary for a holistic understanding of the spread of infectious diseases. One approach to combining these scales is through mathematical modeling. We conducted a systematic review of the published literature on multi-scale mathematical models of disease transmission (as defined by combining within-host and between-host scales) to determine the extent to which mathematical models are being used to understand across-scale transmission, and the extent to which these models are being confronted with data. Following the PRISMA guidelines for systematic reviews, we identified 24 of 197 qualifying papers across 30 years that include both linked models at the within and between host scales and that used data to parameterize/calibrate models. We find that the approach that incorporates both modeling with data is under-utilized, if increasing. This highlights the need for better communication and collaboration between modelers and empiricists to build well-calibrated models that both improve understanding and may be used for prediction.

12.
Nat Commun ; 10(1): 1815, 2019 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-31000717

RESUMO

Colloids are mainly divided into two types defined by size. Micron-scale colloids are widely used as model systems to study phase transitions, while nanoparticles have physicochemical properties unique to their size. Here we study a promising yet underexplored third type: anisometric colloids, which integrate micrometer and nanometer dimensions into the same particle. We show that our prototypical system of anisometric silver plates with a high polydispersity assemble, unexpectedly, into an ordered, three-dimensional lattice. Real-time imaging and interaction modeling elucidate the crucial role of anisometry, which directs hierarchical assembly into secondary building blocks-columns-which are sufficiently monodisperse for further ordering. Ionic strength and plate tip morphology control the shape of the columns, and therefore the final lattice structures (hexagonal versus honeycomb). Our joint experiment-modeling study demonstrates potentials of encoding unconventional assembly in anisometric colloids, which can likely introduce properties and phase behaviors inaccessible to micron- or nanometer-scale colloids.

13.
ACS Appl Mater Interfaces ; 11(8): 8517-8526, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30676014

RESUMO

An understanding of how complex nanoscale morphologies emerge from synthesis would offer powerful strategies to construct soft materials with designed structures and functions. However, these kinds of morphologies have proven difficult to characterize, and therefore manipulate, because they are three-dimensional (3D), nanoscopic, and often highly irregular. Here, we studied polyamide (PA) membranes used in wastewater reclamation as a prime example of this challenge. Using electron tomography and quantitative morphometry, we reconstructed the nanoscale morphology of 3D crumples and voids in PA membranes for the first time. Various parameters governing film transport properties, such as surface-to-volume ratio and mass-per-area, were measured directly from the reconstructed membrane structure. In addition, we extracted information inaccessible by other means. For example, 3D reconstruction shows that membrane nanostructures are formed from PA layers 15-20 nm thick folding into 3D crumples which envelope up to 30% void by volume. Mapping local curvature and thickness in 3D quantitatively groups these crumples into three classes, "domes", "dimples", and "clusters", each being a distinct type of microenvironment. Elemental mapping of metal ion adsorption across the film demonstrates that these previously missed parameters are relevant to membrane performance. This imaging-morphometry platform can be applicable to other nanoscale soft materials and potentially suggests engineering strategies based directly on synthesis-morphology-function relationships.

14.
ACS Macro Lett ; 8(10): 1365-1371, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32149017

RESUMO

Protein aggregation is implicated in multiple deposition diseases including Alzheimer's Disease, which features the formation of toxic aggregates of amyloid beta (Aß) peptides. Many inhibitors have been developed to impede or reverse Aß aggregation. Multivalent inhibitors, however, have been largely overlooked despite the promise of high inhibition efficiency endowed by the multivalent nature of Aß aggregates. In this work, we report the success of multivalent polymer-peptide conjugates (mPPCs) as a general class of inhibitors of the aggregation of Aß40. Significantly delayed onset of fibril formation was realized using mPPCs prepared from three peptide/peptoid ligands covering a range of polymer molecular weights (MWs) and ligand loadings. Dose dependence studies showed that the nature of the ligands is a key factor in mPPC inhibition potency. The negatively charged ligand LPFFD (LD) leads to more efficient mPPCs compared to the neutral ligands, and is most effective at 7% ligand loading across different MWs. Molecular dynamics simulations along with dynamic light scattering experiments suggest that mPPCs form globular structures in solution due to ligand-ligand interactions. Such interactions are key to the spatial proximity of ligands and thus to the multivalency effect of mPPC inhibition. Excess ligand-ligand interactions, however, reduce the accessibility of mPPC ligands to Aß peptides, and impair the overall inhibition potency.

15.
Macromol Rapid Commun ; 39(14): e1800101, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29722094

RESUMO

Reconfigurable hybrid nanoparticles made by decorating flexible polymer shells on rigid inorganic nanoparticle cores can provide a unique means to build stimuli-responsive functional materials. The polymer shell reconfiguration has been expected to depend on the local core shape details, but limited systematic investigations have been undertaken. Here, two literature methods are adapted to coat either thiol-terminated polystyrene (PS) or polystyrene-poly(acrylic acid) (PS-b-PAA) shells onto a series of anisotropic gold nanoparticles of shapes not studied previously, including octahedron, concave cube, and bipyramid. These core shapes are complex, rendering shell contours with nanoscale details (e.g., local surface curvature, shell thickness) that are imaged and analyzed quantitatively using the authors' customized analysis codes. It is found that the hybrid nanoparticles based on the chosen core shapes, when coated with the above two polymer shells, exhibit distinct shell segregations upon a variation in solvent polarity or temperature. It is demonstrated for the PS-b-PAA-coated hybrid nanoparticles, the shell segregation is maintained even after a further decoration of the shell periphery with gold seeds; these seeds can potentially facilitate subsequent deposition of other nanostructures to enrich structural and functional diversity. These synthesis, imaging, and analysis methods for the hybrid nanoparticles of anisotropically shaped cores can potentially aid in their predictive design for materials reconfigurable from the bottom up.


Assuntos
Acrilatos/química , Nanopartículas Metálicas/química , Polímeros/química , Poliestirenos/química , Resinas Acrílicas , Anisotropia , Ouro/química , Tamanho da Partícula , Solventes/química , Propriedades de Superfície
16.
ACS Nano ; 11(8): 7626-7633, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28715193

RESUMO

Highly anisometric nanoparticles have distinctive mechanical, electrical, and thermal properties and are therefore appealing candidates for use as self-assembly building blocks. Here, we demonstrate that ultra-anisometric nanoplates, which have a nanoscale thickness but a micrometer-scale edge length, offer many material design capabilities. In particular, we show that these nanoplates "copolymerize" in a predictable way with patchy spheres (Janus and triblock particles) into one- and two-dimensional structures with tunable architectural properties. We find that, on the pathway to these structures, nanoplates assemble into chains following the kinetics of molecular step-growth polymerization. In the same mechanistic framework, patchy spheres control the size distribution and morphology of assembled structures, by behaving as monofunctional chain stoppers or multifunctional branch points during nanoplate polymerization. In addition, both the lattice constant and the stiffness of the nanoplate assemblies can be manipulated after assembly. We see highly anisometric nanoplates as one representative of a broader class of dual length-scale nanoparticles, with the potential to enrich the library of structures and properties available to the nanoparticle self-assembly toolbox.

17.
Acc Chem Res ; 50(5): 1125-1133, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28443654

RESUMO

For decades, one of the overarching objectives of self-assembly science has been to define the rules necessary to build functional, artificial materials with rich and adaptive phase behavior from the bottom-up. To this end, the computational and experimental efforts of chemists, physicists, materials scientists, and biologists alike have built a body of knowledge that spans both disciplines and length scales. Indeed, today control of self-assembly is extending even to supramolecular and molecular levels, where crystal engineering and design of porous materials are becoming exciting areas of exploration. Nevertheless, at least at the nanoscale, there are many stones yet to be turned. While recent breakthroughs in nanoparticle (NP) synthesis have amassed a vast library of nanoscale building blocks, NP-NP interactions in situ remain poorly quantified, in large part due to technical and theoretical impediments. While increasingly many applications for self-assembled architectures are being demonstrated, it remains difficult to predict-and therefore engineer-the pathways by which these structures form. Here, we describe how investigations using liquid-phase transmission electron microscopy (TEM) have begun to play a role in pursuing some of these long-standing questions of fundamental and far-reaching interest. Liquid-phase TEM is unique in its ability to resolve the motions and trajectories of single NPs in solution, making it a powerful tool for studying the dynamics of NP self-assembly. Since 2012, liquid-phase TEM has been used to investigate the self-assembly behavior of a variety of simple, metallic NPs. In this Account, however, we focus on our work with anisotropic NPs, which we show to have very different self-assembly behavior, and especially on how analysis methods we and others in the field are developing can be used to convert their motions and trajectories revealed by liquid-phase TEM into quantitative understanding of underlying interactions and dynamics. In general, liquid-phase TEM studies may help bridge enduring gaps in the understanding and control of self-assembly at the nanoscale. For one, quantification of NP-NP interactions and self-assembly dynamics will inform both computational and statistical mechanical models used to describe nanoscale phenomena. Such understanding will also lay the groundwork for establishing new and generalizable thermodynamic and kinetic design rules for NP self-assembly. Synergies with NP synthesis will enable investigations of building blocks with novel, perhaps even evolving or active behavior. Moreover, in the long run, we foresee the possibility of applying the guidelines and models of fundamental nanoscale interactions which are uncovered under liquid-phase TEM to biological and biomimetic systems at similar dimensions.

18.
Clin Breast Cancer ; 17(1): 48-54.e3, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27693116

RESUMO

BACKGROUND: The purpose of this study was to determine the cardiac safety and clinical activity of trastuzumab and bevacizumab with docetaxel after epirubicin with cyclophosphamide (EC) in patients with HER2-positive locally advanced breast cancer (LABC) or pathologic stage 3 breast cancer (PS3BC). PATIENTS AND METHODS: Patients received every 3 week treatment with 4 cycles of EC (90/600 mg/m2) followed by 4 cycles of docetaxel (100 mg/m2). Targeted therapy with standard-dose trastuzumab with bevacizumab 15 mg/kg was given for a total of 1 year. Coprimary end points were (1) rate of cardiac events (CEs) in all patients defined as clinical congestive heart failure with a significant decrease in left ventricular ejection fraction or cardiac deaths; and (2) pathologic complete response (pCR) in breast and nodes in the neoadjuvant cohort. An independent cardiac review panel determined whether criteria for a CE were met. RESULTS: A total of 105 patients were accrued, 76 with LABC treated with neoadjuvant therapy and 29 with PS3BC treated with adjuvant therapy. Median follow-up was 59.2 months. Among 99 evaluable patients for cardiac safety, 4 (4%; 95% confidence interval [CI], 1.1%-10.0%) met CE criteria. The pCR percentage in LABC patients was 46% (95% CI, 34%-59%). Five-year recurrence-free survival (RFS) and overall survival (OS) for all patients was 79.9% and 90.8%, respectively. CONCLUSION: The regimen met predefined criteria for activity of interest with an acceptable rate of CEs. Although the pCR percentage was comparable with chemotherapy regimens with trastuzumab alone the high RFS and OS are of interest in these high-risk populations.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Terapia Neoadjuvante , Bevacizumab/administração & dosagem , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Estudos de Coortes , Ciclofosfamida/administração & dosagem , Docetaxel , Epirubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Taxa de Sobrevida , Taxoides/administração & dosagem , Trastuzumab/administração & dosagem
19.
Zootaxa ; 4185(1): zootaxa.4185.1.1, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27988771

RESUMO

Keys are provided for the identification of the nematode species known to be parasites of Canadian fishes. The nematodes are described and illustrated, with a note of the site(s) they occupy in named fish host(s) and their geographical distribution. Parasite records are given by author and date, full details of which can be found in a bibliography of over 800 references. Diagnoses and keys for 22 Families, 47 genera and 88 species of nematodes are also given, together with a glossary of terms, a host-parasite list, and indices to both nematode parasites and hosts.


Assuntos
Peixes/parasitologia , Nematoides/anatomia & histologia , Nematoides/classificação , Animais , Canadá , Feminino , Doenças dos Peixes/parasitologia , Masculino , Infecções por Nematoides/veterinária , Especificidade da Espécie
20.
Clin Breast Cancer ; 16(1): 31-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26433876

RESUMO

BACKGROUND: The present phase II, open-label, multicenter study explored the feasibility, safety, and tolerability of eribulin, a novel non-taxane microtubule inhibitor, plus capecitabine as adjuvant therapy. PATIENTS AND METHODS: Postmenopausal women with early-stage, human epidermal growth factor receptor 2 (HER2)-negative, estrogen-receptor (ER)-positive breast cancer received four 21-day cycles of treatment with eribulin mesylate (1.4 mg/m(2) intravenously on days 1 and 8 of each cycle) combined with capecitabine (900 mg/m(2) orally twice daily on days 1-14 of each cycle [standard schedule] or 1500 mg orally twice daily using a 7-days on/7-days off schedule [weekly schedule]). Feasibility was determined by the relative dose intensity (RDI) of the combination using prespecified criteria for 80% of patients achieving an RDI of ≥ 85%, with a lower 95% confidence boundary > 70%. RESULTS: The mean RDI was 90.6%, and the feasibility rate was 81.3% among women (n = 67, mean age, 61.3 years) receiving the standard schedule and 95.6% and 100% among women (n = 10, mean age 62.3 years) receiving the weekly schedule. Dose reductions, missed doses, and withdrawals due to adverse events (most commonly hand-foot syndrome) ascribed to capecitabine led to a higher RDI (93.5% vs. 87.8%) and feasibility rate (82.8% vs. 71.9%) for eribulin than for capecitabine using the standard dosing schedule. The most common adverse events were alopecia and fatigue. CONCLUSION: Eribulin plus capecitabine with standard or weekly dosing schedules is feasible in patients with early-stage, HER2-negative, ER-positive breast cancer. Full-dose eribulin (1.4 mg/m(2) on days 1 and 8) with capecitabine (1500 mg orally twice daily, 7 days on/7 days off) is recommended as a regimen for further evaluation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Capecitabina/administração & dosagem , Capecitabina/efeitos adversos , Estudos de Viabilidade , Feminino , Furanos/administração & dosagem , Furanos/efeitos adversos , Humanos , Cetonas/administração & dosagem , Cetonas/efeitos adversos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pós-Menopausa
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