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1.
Biol Reprod ; 111(1): 54-62, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38590174

RESUMEN

The objective was to identify a set of genes whose transcript abundance is predictive of a cow's ability to become pregnant following artificial insemination. Endometrial epithelial cells from the uterine body were collected for RNA sequencing using the cytobrush method from 193 first-service Holstein cows at estrus prior to artificial insemination (day 0). A group of 253 first-service cows not used for cytobrush collection were controls. There was no effect of cytobrush collection on pregnancy outcomes at day 30 or 70 or on pregnancy loss between days 30 and 70. There were 2 upregulated and 214 downregulated genes (false discovery rate < 0.05, absolute fold change >2-fold) for cows pregnant at day 30 versus those that were not pregnant. Functional terms overrepresented in the downregulated genes included those related to immune and inflammatory responses. Machine learning for fertility biomarkers with the R package BORUTA resulted in identification of 57 biomarkers that predicted pregnancy outcome at day 30 with an average accuracy of 77%. Thus, machine learning can identify predictive biomarkers of pregnancy in endometrium with high accuracy. Moreover, sampling of endometrial epithelium using the cytobrush can help understand functional characteristics of the endometrium at artificial insemination without compromising cow fertility. Functional characteristics of the genes comprising the set of biomarkers is indicative that a major determinant of cow fertility, at least for first insemination after calving, is immune status of the uterus, which, in turn, is likely to reflect the previous history of uterine disease.


Asunto(s)
Biomarcadores , Endometrio , Inseminación Artificial , Aprendizaje Automático , Femenino , Animales , Inseminación Artificial/veterinaria , Bovinos , Embarazo , Endometrio/metabolismo , Biomarcadores/metabolismo , Resultado del Embarazo/veterinaria
2.
Soft Matter ; 20(17): 3577-3584, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38629336

RESUMEN

Most cells take simple sugar (α-D-glucose) and assemble it into highly dense polysaccharide nanoparticles called glycogen. This is achieved through the action of multiple coupled-enzymatic reactions, yielding the cellular store of polymerised glucose to be degraded in times of metabolic need. These nanoparticles can be readily isolated from various animal tissues and plants, and are commercially available on a large scale. Importantly, glycogen is highly water soluble, non-toxic, low-fouling, and biodegradable, making it an attractive nanoparticle for use in nanomedicine, for both diagnosing and treating disease. This concept has been pursued actively recently, with exciting results on a variety of fronts, especially for targeting specific tissues and delivering nucleic acid and peptide cargo. In this perspective, the role of glycogen in nanomedicine going forward is discussed, with opportunities highlighted of where these sugary nanoparticles fit into the problem of treating disease.


Asunto(s)
Glucógeno , Nanomedicina , Nanopartículas , Glucógeno/metabolismo , Glucógeno/química , Nanopartículas/química , Humanos , Animales , Polímeros/química
3.
Physiol Genomics ; 55(11): 557-564, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37720990

RESUMEN

The objectives of the present study were to characterize the expression of genes encoding for cell signaling ligands in the bovine endosalpinx and endometrium and analyze spatial changes in gene expression. RNA sequencing was performed for the endosalpinx from the ampulla of the oviduct and endometrium from the upper and middle uterine horn and uterine body at day 2 after ovulation from ipsilateral and contralateral sides relative to the ovulatory ovary. Of the 17,827 unique mRNA transcripts mapped, 2,072 were affected by cranial-caudal position in the reproductive tract and 818 were affected by side (false discovery rate < 0.05). There were 334 genes encoding for cell signaling ligands, with 128 genes having greater than two transcripts per million on average. A total of 81 cell signaling ligand genes were affected by position and 24 were affected by side. A data set of the transcriptome of two to four cell embryos was used to identify cell signaling ligand genes that were highly expressed in the ampulla for which there was high expression of the receptor in the embryo. The most expressed ligand-receptor pairs were PSAP/SORT1, MIF/CXCR4, GPI/AMFR, and KITLG/KIT. These cell signaling ligands, as well as others whose gene is expressed in the endosalpinx and endometrium, may influence early embryonic development. Spatial changes throughout the reproductive tract highlight the distinctive expression profile of the oviduct versus the endometrium, including a set of the identified genes encoding for cell signaling ligands, and highlight the local influence of the ovary. The results also show the continuity of expression for large numbers of genes in the reproductive tract.NEW & NOTEWORTHY Examination of the transcriptome of the endosalpinx and endometrium revealed the degree to which gene expression in the reproductive tract varies spatially. The expression of genes encoding cell signaling molecules that could potentially regulate embryonic development was also identified.


Asunto(s)
Endometrio , Transcriptoma , Embarazo , Femenino , Bovinos , Animales , Transcriptoma/genética , Ligandos , Endometrio/metabolismo , Perfilación de la Expresión Génica , Útero/metabolismo
4.
Am J Physiol Heart Circ Physiol ; 324(4): H391-H410, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36607797

RESUMEN

This study reports a new methodology for right heart imaging by ultrasound in mice under right ventricular (RV) pressure overload. Pulmonary artery constriction (PAC) or sham surgeries were performed on C57BL/6 male mice at 8 wk of age. Ultrasound imaging was conducted at 2, 4, and 8 wk postsurgery using both classical and advanced ultrasound imaging modalities including electrocardiogram (ECG)-based kilohertz visualization, anatomical M-mode, and strain imaging. Based on pulsed Doppler, the PAC group demonstrated dramatically enhanced pressure gradient in the main pulmonary artery (MPA) as compared with the sham group. By the application of advanced imaging modalities in novel short-axis views of the ventricles, the PAC group demonstrated increased thickness of RV free wall, enlarged RV chamber, and reduced RV fractional shortening compared with the sham group. The PAC group also showed prolonged RV contraction, asynchronous interplay between RV and left ventricle (LV), and passive leftward motion of the interventricular septum (IVS) at early diastole. Consequently, the PAC group exhibited prolongation of LV isovolumic relaxation time, without change in LV wall thickness or systolic function. Significant correlations were found between the maximal pressure gradient in MPA measured by Doppler and the RV systolic pressure by catheterization, as well as the morphological and functional parameters of RV by ultrasound.NEW & NOTEWORTHY The established protocol overcomes the challenges in right heart imaging in mice, thoroughly elucidating the changes of RV, the dynamics of IVS, and the impact on LV and provides new insights into the pathophysiological mechanism of RV remodeling.


Asunto(s)
Disfunción Ventricular Derecha , Remodelación Ventricular , Masculino , Animales , Ratones , Ratones Endogámicos C57BL , Corazón , Ventrículos Cardíacos/diagnóstico por imagen , Ultrasonografía , Disfunción Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/etiología , Presión Ventricular/fisiología , Función Ventricular Derecha
5.
Langmuir ; 39(14): 4872-4880, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-36995334

RESUMEN

Polymer brushes, i.e., end-tethered polymer chains on substrates, are sensitive to adaptation, e.g., swelling, adsorption, and reorientation of the surface molecules. This adaptation can originate from a contacting liquid or atmosphere for partially wetted substrates. The macroscopic contact angle of the aqueous drop can depend on both adaptation mechanisms. We analyze how the atmosphere around an aqueous droplet determines the resulting contact angle of the wetting droplet on polymer brush surfaces. Poly(N-isopropylacrylamide) (PNiPAAm)-based brushes are used due to their exceptional sensitivity to solvation and liquid mixture composition. We develop a method that reliably measures wetting properties when the drop and the surrounding atmosphere are not in equilibrium, e.g., when evaporation and condensation tend to contaminate the liquid of the drop and the atmosphere. For this purpose, we use a coaxial needle in the droplet, which continuously exchanges the wetting liquid, and in addition, we constantly exchange the almost saturated atmosphere. Depending on the wetting history, PNiPAAm can be prepared in two states, state A with a large water contact angle (∼65°) and state B with a small water contact angle (∼25°). With the coaxial needle, we can demonstrate that the water contact angle of a sample in state B significantly increases by ∼30° when a water-free atmosphere is almost saturated with ethanol, compared to an ethanol-free atmosphere at 50% relative humidity. For a sample in state A, the relative humidity has little influence on the water contact angle.

6.
J Hand Surg Am ; 2023 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-37516939

RESUMEN

PURPOSE: Thumb carpometacarpal (CMC) osteoarthritis (OA) causes functional disability and an increased health care burden in the aging population. The role of therapy in thumb CMC OA has been minimally analyzed in the literature. We hypothesized that patients treated with therapy for thumb CMC OA would demonstrate reduced rates of surgery for this diagnosis. METHODS: We queried a national insurance dataset for all patients with an International Classification of Diseases, Ninth Revision, or International Statistical Classification of Diseases, Tenth Revision, code for thumb CMC OA, with a minimum of 2 years of follow-up. A 2:1 propensity-matched cohort of patients with CMC OA who did not receive therapy versus a therapy cohort was created, with a minimum of two sessions of hand therapy for inclusion. The primary outcome was the rate of thumb CMC OA surgery occurring within 2 years of diagnosis; time to surgery and use of thumb CMC injections were secondary outcomes. Multivariable logistic regression analysis was used to identify the risk factors for undergoing surgical treatment. RESULTS: After matching, the therapy cohort comprised 14,548 patients, with a matched group of 28,930 patients who did not undergo therapy. In the overall sample, the rate of surgery within 2 years was 22.5%. Two-year surgical treatment rates were significantly higher for those who did not undergo therapy when compared with those who did (29.3% vs 13.1%). Patients treated with therapy had a significantly longer time to surgery, with no difference in the rate of surgery after one year. In multivariable regression of all included variables, lack of therapy intervention had the highest odds of surgery for thumb CMC OA (odds ratio 4.3). CONCLUSIONS: We present the findings of a large insurance database evaluating the association of therapy with rates of surgical treatment for thumb CMC arthritis. On average, those treated with therapy had longer times to surgery, and the 2-year surgery rates for patients diagnosed with thumb CMC arthritis were significantly higher in those who did not undergo therapy treatment. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.

7.
Eur J Orthop Surg Traumatol ; 33(4): 1091-1099, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35380277

RESUMEN

PURPOSE: Ballistic fractures of the femoral condyles are rare injuries with limited literature to help guide treatment. The purpose of this study is to report on the presentation, management, and outcomes for patients with isolated ballistic condylar fractures. METHODS: Eighteen patients between ages 16 and 65 with low-energy ballistic injuries isolated to the femoral condyles (OTA 33B) were included, 15 with CT imaging. Clinical records and imaging were reviewed, as well as treatment strategy. Fractures were classified by AO/OTA classification. Outcome and follow-up data were gathered at outpatient appointments and telephone calls. RESULTS: Of the 18 patients, 78% were treated operatively (61% with open reduction and internal fixation, 17% with removal of foreign body alone). There were two instances of traumatic vascular injury and no neurologic injuries. Furthermore, there were no identified infections. Only 58% of the patients had follow-up for more than 6 weeks with average KOOS Jr. Score of 50, and average VAS pain score of 5.2. CONCLUSIONS: Ballistic femoral condyle fractures are rare Orthopaedic injuries seen in relatively high frequency at our institution. Most (78%) were treated operatively and with few complications. These fractures are not easily classified according to common classification schemes and may benefit from more rigorous study to guide treatment and anticipate outcomes.


Asunto(s)
Fracturas del Fémur , Fracturas del Cuello Femoral , Fracturas de Rodilla , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Fijación Interna de Fracturas/métodos , Fémur , Fracturas del Fémur/cirugía , Resultado del Tratamiento
8.
Am J Respir Cell Mol Biol ; 67(5): 562-573, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35926106

RESUMEN

Pulmonary hypertension (PH) is a multifaceted condition characterized by elevated pulmonary arterial pressure, which can result in right ventricular dysfunction and failure. Disorders of lung development can present with secondary PH, which is a leading cause of mortality in infants with bronchopulmonary dysplasia (BPD). DDR1 (discoidin domain receptor 1) is a collagen-binding receptor that regulates tissue fibrosis and inflammation and controls cellular growth and migration. However, the roles of DDR1 in lung development or the pathogenesis of PH are unknown. Studying mice with a DDR1 deletion (Ddr1-/-), we have noted 35% mortality between 1 and 4 months of age, and we demonstrate that DDR1 deficiency results in reduced right ventricular contractility and muscularization of distal pulmonary arteries, consistent with PH. Pathology analysis revealed enlarged alveolar spaces in Ddr1-/- mice by Postnatal Day 7, consistent with impaired alveolar development. Gene expression analysis showed that Ddr1-/- mice have reduced concentrations of alveologenesis factors and epithelial-to-mesenchymal transition markers. Mechanistic studies in vitro confirmed that DDR1 mediated epithelial-to-mesenchymal transition, migration, and growth of alveolar epithelial cells. Taken together, these data suggest that DDR1 plays important roles mediating alveolarization during lung development. Our studies also describe a new model of spontaneous PH and bronchopulmonary dysplasia in mice.


Asunto(s)
Displasia Broncopulmonar , Receptor con Dominio Discoidina 1 , Hipertensión Pulmonar , Animales , Humanos , Recién Nacido , Ratones , Receptor con Dominio Discoidina 1/genética , Receptor con Dominio Discoidina 1/metabolismo , Transición Epitelial-Mesenquimal/fisiología , Fibrosis
9.
Small ; 18(12): e2107557, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35146916

RESUMEN

Developing facile methods for inducing phase transformation between metallic and semiconducting 2D transition metal dichalcogenide (TMDC) materials is crucial toward leveraging their use in cutting-edge energy devices. Herein, 2H-to-1T' phase transformations in chemically exfoliated Tungsten Disulfide (WS2 ) nanosheet films, triggered by antioxidants toward highly conductive 2D TMDC electrode materials, are introduced. It is found that antioxidants cause residual LiOx compounds to reduce to Li metal, subsequently inducing 1T' phase transformations in layered WS2 nanosheets, resulting in significantly enhanced conductivity across the overall films. Both thermoelectric devices and supercapacitors are fabricated utilizing the highly conductive 1T' phase WS2 nanosheet films as a working electrode, allowing for outstanding performance due to the increased conductivity of the WS2 nanosheet films. The method constitutes a facile approach toward the use of chemically exfoliated 1T' TMDC nanosheets for highly efficient energy device applications.

10.
Planta ; 255(4): 74, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35226202

RESUMEN

MAIN CONCLUSION: Droughted sorghum had higher concentrations of ROS in both wildtype and dhurrin-lacking mutants. Dhurrin increased in wildtype genotypes with drought. Dhurrin does not appear to mitigate oxidative stress in sorghum. Sorghum bicolor is tolerant of high temperatures and prolonged droughts. During droughts, concentrations of dhurrin, a cyanogenic glucoside, increase posing a risk to livestock of hydrogen cyanide poisoning. Dhurrin can also be recycled without the release of hydrogen cyanide presenting the possibility that it may have functions other than defence. It has been hypothesised that dhurrin may be able to mitigate oxidative stress by scavenging reactive oxygen species (ROS) during biosynthesis and recycling. To test this, we compared the growth and chemical composition of S. bicolor in total cyanide deficient sorghum mutants (tcd1) with wild-type plants that were either well-watered or left unwatered for 2 weeks. Plants from the adult cyanide deficient class of mutant (acdc1) were also included. Foliar dhurrin increased in response to drought in all lines except tcd1 and acdc1, but not in the roots or leaf sheaths. Foliar ROS concentration increased in drought-stressed plants in all genotypes. Phenolic concentrations were also measured but no differences were detected. The total amounts of dhurrin, ROS and phenolics on a whole plant basis were lower in droughted plants due to their smaller biomass, but there were no significant genotypic differences. Up until treatments began at the 3-leaf stage, tcd1 mutants grew more slowly than the other genotypes but after that they had higher relative growth rates, even when droughted. The findings presented here do not support the hypothesis that the increase in dhurrin commonly seen in drought-stressed sorghum plays a role in reducing oxidative stress by scavenging ROS.


Asunto(s)
Sorghum , Cianuro de Hidrógeno , Nitrilos , Estrés Oxidativo , Sorghum/química
11.
Molecules ; 27(9)2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35566393

RESUMEN

Molecular permeability through polymer brush chains is implicated in surface lubrication, wettability, and solute capture and release. Probing molecular transport through polymer brushes can reveal information on the polymer nanostructure, with a permeability that is dependent on chain conformation and grafting density. Herein, we introduce a brush system to study the molecular transport of fluorophores from an aqueous droplet into the external "dry" polymer brush with the vapour phase above. The brushes consist of a random copolymer of N-isopropylacrylamide and a Förster resonance energy transfer (FRET) donor-labelled monomer, forming ultrathin brush architectures of about 35 nm in solvated height. Aqueous droplets containing a separate FRET acceptor are placed onto the surfaces, with FRET monitored spatially around the 3-phase contact line. FRET is used to monitor the transport from the droplet to the outside brush, and the changing internal distributions with time as the droplets prepare to recede. This reveals information on the dynamics and distances involved in the molecular transport of the FRET acceptor towards and away from the droplet contact line, which are strongly dependent on the relative humidity of the system. We anticipate our system to be extremely useful for studying lubrication dynamics and surface droplet wettability processes.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Polímeros , Polímeros/química , Soluciones , Agua , Humectabilidad
12.
Behav Res Methods ; 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36085543

RESUMEN

Assessing gaze behavior during real-world tasks is difficult; dynamic bodies moving through dynamic worlds make gaze analysis difficult. Current approaches involve laborious coding of pupil positions. In settings where motion capture and mobile eye tracking are used concurrently in naturalistic tasks, it is critical that data collection be simple, efficient, and systematic. One solution is to combine eye tracking with motion capture to generate 3D gaze vectors. When combined with tracked or known object locations, 3D gaze vector generation can be automated. Here we use combined eye and motion capture and explore how linear regression models generate accurate 3D gaze vectors. We compare spatial accuracy of models derived from four short calibration routines across three pupil data inputs: the efficacy of calibration routines was assessed, a validation task requiring short fixations on task-relevant locations, and a naturalistic object interaction task to bridge the gap between laboratory and "in the wild" studies. Further, we generated and compared models using spherical and Cartesian coordinate systems and monocular (left or right) or binocular data. All calibration routines performed similarly, with the best performance (i.e., sub-centimeter errors) coming from the naturalistic task trials when the participant is looking at an object in front of them. We found that spherical coordinate systems generate the most accurate gaze vectors with no differences in accuracy when using monocular or binocular data. Overall, we recommend 1-min calibration routines using binocular pupil data combined with a spherical world coordinate system to produce the highest-quality gaze vectors.

13.
J Am Chem Soc ; 143(26): 9972-9981, 2021 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34170661

RESUMEN

Surface chemistry is a major factor that determines the wettability of materials, and devising broadly applicable coating strategies that afford tunable and selective surface properties required for next-generation materials remains a challenge. Herein, we report fluorinated metal-organic coatings that display water-wetting and oil-repelling characteristics, a wetting phenomenon different from responsive wetting induced by external stimuli. We demonstrate this selective wettability with a library of metal-organic coatings using catechol-based coordination and silanization (both fluorinated and fluorine-free), enabling sensing through interfacial reconfigurations in both gaseous and liquid environments, and establish a correlation between the coating wettability and polarity of the liquids. This selective wetting performance is substrate-independent, spontaneous, durable, and reversible and occurs over a range of polar and nonpolar liquids (60 studied). These results provide insight into advanced liquid-solid interactions and a pathway toward tuning interfacial affinities and realizing robust, selective superwettability according to the surrounding conditions.

14.
Biomacromolecules ; 22(2): 612-619, 2021 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-33337863

RESUMEN

Poly(ethylene glycol) (PEG) is well known to endow nanoparticles (NPs) with low-fouling and stealth-like properties that can reduce immune system clearance in vivo, making PEG-based NPs (particularly sub-100 nm) of interest for diverse biomedical applications. However, the preparation of sub-100 nm PEG NPs with controllable size and morphology is challenging. Herein, we report a strategy based on the noncovalent coordination between PEG-polyphenolic ligands (PEG-gallol) and transition metal ions using a water-in-oil microemulsion phase to synthesize sub-100 nm PEG NPs with tunable size and morphology. The metal-phenolic coordination drives the self-assembly of the PEG-gallol/metal NPs: complexation between MnII and PEG-gallol within the microemulsions yields a series of metal-stabilized PEG NPs, including 30-50 nm solid and hollow NPs, depending on the MnII/gallol feed ratio. Variations in size and morphology are attributed to the changes in hydrophobicity of the PEG-gallol/MnII complexes at varying MnII/gallol ratios based on contact angle measurements. Small-angle X-ray scattering analysis, which is used to monitor the particle size and intermolecular interactions during NP evolution, reveals that ionic interactions are the dominant driving force in the formation of the PEG-gallol/MnII NPs. pH and cytotoxicity studies, and the low-fouling properties of the PEG-gallol/MnII NPs confirm their high biocompatibility and functionality, suggesting that PEG polyphenol-metal NPs are promising systems for biomedical applications.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Interacciones Hidrofóbicas e Hidrofílicas , Tamaño de la Partícula , Polietilenglicoles
15.
J Chem Inf Model ; 61(9): 4521-4536, 2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34406000

RESUMEN

Water is a unique solvent that is ubiquitous in biology and present in a variety of solutions, mixtures, and materials settings. It therefore forms the basis for all molecular dynamics simulations of biological phenomena, as well as for many chemical, industrial, and materials investigations. Over the years, many water models have been developed, and it remains a challenge to find a single water model that accurately reproduces all experimental properties of water simultaneously. Here, we report a comprehensive comparison of structural and dynamic properties of 30 commonly used 3-point, 4-point, 5-point, and polarizable water models simulated using consistent settings and analysis methods. For the properties of density, coordination number, surface tension, dielectric constant, self-diffusion coefficient, and solvation free energy of methane, models published within the past two decades consistently show better agreement with experimental values compared to models published earlier, albeit with some notable exceptions. However, no single model reproduced all experimental values exactly, highlighting the need to carefully choose a water model for a particular study, depending on the phenomena of interest. Finally, machine learning algorithms quantified the relationship between the water model force field parameters and the resulting bulk properties, providing insight into the parameter-property relationship and illustrating the challenges of developing a water model that can accurately reproduce all properties of water simultaneously.


Asunto(s)
Simulación de Dinámica Molecular , Agua , Solventes , Termodinámica
16.
J Chem Phys ; 155(7): 074505, 2021 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-34418930

RESUMEN

Deep Eutectic Solvents (DESs) are complex solutions that present unique challenges compared to traditional solvents. Unlike most aqueous electrolytes and ionic liquids, DESs have delicate hydrogen bond networks that are responsible for their highly sensitive compositional dependence on the melting point. Prior work has demonstrated a unique nanoscale structure both experimentally and theoretically that brings both challenges and opportunities to their adoption in traditional electrochemical processes. In this study, we use in situ sample-rotated ultra-small angle x-ray scattering to resolve the near-interface solvent structure after electrodepositing Pd nanoparticles onto a glassy carbon electrode in choline chloride:urea and choline chloride:ethylene glycol DESs. Our results indicate that a hierarchical solvent structure can be observed on the meso-scale in the choline chloride:urea and choline chloride:ethylene glycol systems. Importantly, this extended solvent structure increases between -0.3 V and -0.5 V (vs Ag/AgCl) and remains high until -0.9 V (vs Ag/AgCl). Experimentally, the nature of this structure is more pronounced in the ethylene glycol system, as evidenced by both the x-ray scattering and the electrochemical impedance spectroscopy. Molecular dynamics simulations and dipolar orientation analysis reveal that chloride delocalization near the Pd interface and long-range interactions between the choline and each hydrogen bond donor (HBD) are very different and qualitatively consistent with the experimental data. These results show how the long-range solvent-deposit interactions can be tuned by changing the HBD in the DES and the applied potential.

17.
Luminescence ; 36(4): 1097-1106, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33617125

RESUMEN

Multicolor chemiluminescent acridinium derivatives were synthesized by attaching various common fluorophores to the N10 -acridinium position through a piperazine linker. Triggering of each acridinium derivative using alkaline hydrogen peroxide resulted in a chemiluminescence spectrum dominated by a strong emission (>95%) from the attached fluorophore. The highly quenched emission from the triggered acridinium, acting as a donor, points to a highly efficient intramolecular energy transfer in acridinium-based chemiluminophore-fluorophore tandems. A variable, and in many cases minimal, spectral overlap between the donor emission and the acceptor absorption may indicate that in such tandems the energy transfer follows the Dexter electron exchange mechanism. Moreover, fluorophores affixed through the acridinium 9-position produce a typical acridinium emission profile, demonstrating the need for close distances and favorable intramolecular orientation of the donor and acceptor moieties for the energy transfer to occur. A family of red-shifted chemiluminescent labels, all sharing a uniform triggering method, will find immediate application in multicolor ligand-receptor assays. Along with the multiplexing capabilities, the red-shifted chemiluminescent detection offers a higher tolerance to green-colored biological interferences and will therefore benefit many screening and diagnostic clinical tests.


Asunto(s)
Acridinas , Luminiscencia , Peróxido de Hidrógeno , Mediciones Luminiscentes
18.
Nano Lett ; 20(4): 2660-2666, 2020 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-32155075

RESUMEN

The orientation-specific immobilization of antibodies onto nanoparticles, to preserve antibody-antigen recognition, is a key challenge in developing targeted nanomedicines. Herein, we report the targeting ability of metal-phenolic network (MPN)-coated gold nanoparticles with surface-physisorbed antibodies against respective antigens. The MPN coatings were self-assembled from metal ions (FeIII, CoII, CuII, NiII, or ZnII) cross-linked with tannic acid. Upon physisorption of antibodies, all particle systems exhibited enhanced association with target antigens, with CoII systems demonstrating more than 2-fold greater association. These systems contained more metal atoms distributed in a way to specifically interact with antibodies, which were investigated by molecular dynamics simulations. A model antibody fragment crystallizable (Fc) region in solution with CoII-tannic acid complexes revealed that the solvent-exposed CoII can directly coordinate to the histidine-rich portion of the Fc region. This one-pot interaction suggests anchoring of the antibody Fc region to the MPN on nanoparticles, allowing for enhanced targeting.


Asunto(s)
Anticuerpos Inmovilizados/química , Cobalto/química , Colorantes Fluorescentes/química , Oro/química , Nanopartículas del Metal/química , Taninos/química , Animales , Línea Celular , Reactivos de Enlaces Cruzados/química , Humanos , Inmunoglobulina G/química , Simulación de Dinámica Molecular
19.
Angew Chem Int Ed Engl ; 60(30): 16600-16606, 2021 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-33979032

RESUMEN

Polymer brush surfaces that alter their physical properties in response to chemical stimuli have the capacity to be used as new surface-based sensing materials. For such surfaces, detecting the polymer conformation is key to their sensing capabilities. Herein, we report on FRET-integrated ultrathin (<70 nm) polymer brush surfaces that exhibit stimuli-dependent FRET with changing brush conformation. Poly(N-isopropylacrylamide) polymers were chosen due their exceptional sensitivity to liquid mixture compositions and their ability to be assembled into well-defined polymer brushes. The brush transitions were used to optically sense changes in liquid mixture compositions with high spatial resolution (tens of micrometers), where the FRET coupling allowed for noninvasive observation of brush transitions around complex interfaces with real-time sensing of the liquid environment. Our methods have the potential to be leveraged towards greater surface-based sensing capabilities at intricate interfaces.

20.
Neuroimage ; 215: 116818, 2020 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-32276062

RESUMEN

Even in response to simple tasks such as hand movement, human brain activity shows remarkable inter-subject variability. Recently, it has been shown that individual spatial variability in fMRI task responses can be predicted from measurements collected at rest; suggesting that the spatial variability is a stable feature, inherent to the individual's brain. However, it is not clear if this is also true for individual variability in the spatio-spectral content of oscillatory brain activity. Here, we show using MEG (N â€‹= â€‹89) that we can predict the spatial and spectral content of an individual's task response using features estimated from the individual's resting MEG data. This works by learning when transient spectral 'bursts' or events in the resting state tend to reoccur in the task responses. We applied our method to motor, working memory and language comprehension tasks. All task conditions were predicted significantly above chance. Finally, we found a systematic relationship between genetic similarity (e.g. unrelated subjects vs. twins) and predictability. Our approach can predict individual differences in brain activity and suggests a link between transient spectral events in task and rest that can be captured at the level of individuals.


Asunto(s)
Encéfalo/fisiología , Magnetoencefalografía/métodos , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Descanso/fisiología , Adulto , Mapeo Encefálico/métodos , Electromiografía/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Adulto Joven
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