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1.
J Am Chem Soc ; 146(4): 2736-2747, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38227768

RESUMO

Barocaloric effects─solid-state thermal changes induced by the application and removal of hydrostatic pressure─offer the potential for energy-efficient heating and cooling without relying on volatile refrigerants. Here, we report that dialkylammonium halides─organic salts featuring bilayers of alkyl chains templated through hydrogen bonds to halide anions─display large, reversible, and tunable barocaloric effects near ambient temperature. The conformational flexibility and soft nature of the weakly confined hydrocarbons give rise to order-disorder phase transitions in the solid state that are associated with substantial entropy changes (>200 J kg-1 K-1) and high sensitivity to pressure (>24 K kbar-1), the combination of which drives strong barocaloric effects at relatively low pressures. Through high-pressure calorimetry, X-ray diffraction, and Raman spectroscopy, we investigate the structural factors that influence pressure-induced phase transitions of select dialkylammonium halides and evaluate the magnitude and reversibility of their barocaloric effects. Furthermore, we characterize the cyclability of thin-film samples under aggressive conditions (heating rate of 3500 K s-1 and over 11,000 cycles) using nanocalorimetry. Taken together, these results establish dialkylammonium halides as a promising class of pressure-responsive thermal materials.

2.
World J Clin Cases ; 11(24): 5789-5796, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37727714

RESUMO

BACKGROUND: Atrial arrhythmias such as paroxysmal supraventricular tachycardia (PSVT) and atrial flutter (AF) are common in the perioperative setting. They commonly resolve spontaneously. However, occasionally, they may continually progress to fatal arrhythmias or cause complications. Therefore, prompt and appropriate management is important. CASE SUMMARY: A 46-year-old female patient diagnosed with cervical C6-7 radiculopathy characterized by decreased sensation in the right third, fourth and fifth fingers underwent C6-7 anterior cervical disc fusion surgery. Electrocardiography showed PSVT and ventricular tachycardia during C6-7 disc retraction. However, the patient remained stable. Initial treatment with esmolol and lidocaine for ventricular tachycardia was ineffective. Carotid massage and Valsalva maneuver were attempted but PSVT did not resolve. The surgery was paused, and the patient's fraction of inspired oxygen was set to 100%. Adenosine was administered for pharmacological management of PSVT. The arrhythmia temporarily resolved. However, it then transformed into AF. Diltiazem was administered, which briefly decreased blood pressure, which immediately recovered. Surgery resumed while the patient was in normal sinus rhythm. She was discharged safely on postoperative day 6 without complications or abnormalities. Currently, she is living a healthy life without arrhythmia recurrence. CONCLUSION: Ganglia associated with cardiac arrhythmias in the surgical site should be identified during cervical spine surgery.

3.
Angew Chem Int Ed Engl ; 62(20): e202303115, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-36929595

RESUMO

Accumulation of end-of-life plastics presents ongoing environmental concerns. One strategy to solve this grand challenge is to invent new techniques that modify post-consumer waste and impart new functionality. While promising approaches for the chemical upcycling of commodity polyolefins and polyaromatics exist, analogous approaches to repurpose unsaturated polymers (e.g., polybutadiene) are scarce. In this work, we propose a method to upcycle polybutadiene, one of the most widely used commercial rubbers, via a mild, metal-free allylic amination reaction. The resulting materials have tunable thermal and surface wetting properties as a function of both sulfonamide identity and grafting density. Importantly, this approach maintains the parent alkene microstructure without evidence of olefin reduction, olefin transposition, and/or chain scission. Based on these findings, we anticipate future applications in the remediation of complex elastomers and vulcanized rubbers.

4.
Ecotoxicol Environ Saf ; 253: 114653, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36812868

RESUMO

In-water cleaning (IWC) involves the removal of biofilms and foulants from the hull of a ship using brush or water jet. During IWC, several factors associated with the harmful chemical contaminants release to the marine environment, which can create "hotspots" of chemical contamination in coastal areas. To elucidate the potential toxic effects of IWC discharge, we investigated developmental toxicity in embryonic flounder, which are sensitive life stage to chemical exposure. Zinc and copper were the dominant metals, while zinc pyrithione was the most abundant biocide associated with IWC discharge in two remotely operated IWC. Discharge from IWC carried by both remotely operated vehicles (ROVs) produced developmental malformations including pericardial edema, spinal curvature, and tail-fin defects. In an analyses of differential gene expression profiles (fold-change of genes with a cutoff < 0.05) as assessed by high-throughput RNA sequencing, genes associated with muscle development were commonly and significantly changed. The gene ontology (GO) of embryos exposed to IWC discharge from ROV A activities highly enriched muscle and heart development, while cell signaling and transport were evident in embryos exposed to IWC discharge of ROV B. We analyzed the gene network by significant GO terms. In the network, TTN, MYOM1, CASP3, and CDH2 genes appeared to be key regulators of the toxic effects on muscle development. In embryos exposed to ROV B discharge, HSPG2, VEGFA, and TNF genes related to the nervous system pathway were affected. These results shed light on the potential impacts of muscle and nervous system development in non-target coastal organisms exposed to contaminants found in IWC discharge.


Assuntos
Procedimentos Cirúrgicos Robóticos , Poluentes Químicos da Água , Animais , Água/química , Peixes , Metais/farmacologia , Biofilmes , Poluentes Químicos da Água/análise , Embrião não Mamífero
5.
Nat Commun ; 13(1): 2536, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35534457

RESUMO

Pressure-induced thermal changes in solids-barocaloric effects-can be used to drive cooling cycles that offer a promising alternative to traditional vapor-compression technologies. Efficient barocaloric cooling requires materials that undergo reversible phase transitions with large entropy changes, high sensitivity to hydrostatic pressure, and minimal hysteresis, the combination of which has been challenging to achieve in existing barocaloric materials. Here, we report a new mechanism for achieving colossal barocaloric effects that leverages the large volume and conformational entropy changes of hydrocarbon order-disorder transitions within the organic bilayers of select two-dimensional metal-halide perovskites. Significantly, we show how the confined nature of these order-disorder phase transitions and the synthetic tunability of layered perovskites can be leveraged to reduce phase transition hysteresis through careful control over the inorganic-organic interface. The combination of ultralow hysteresis and high pressure sensitivity leads to colossal reversible isothermal entropy changes (>200 J kg-1 K-1) at record-low pressures (<300 bar).

6.
Ann Dermatol ; 34(2): 87-94, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35450315

RESUMO

Olfactory receptors are chemosensory receptors that detect odorants and function in the initial perception of a smell. Intriguingly, olfactory receptors are also expressed in cells other than olfaction sensory cells, an expression pattern termed ectopic expression. Ectopically expressed olfactory receptors have a distinct role depending on the type of tissues or cells in which they are expressed. This review introduces current research on the ectopic expression and function of olfactory receptors in skin and provides insight into directions for future research.

7.
J Am Chem Soc ; 144(14): 6493-6503, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35360899

RESUMO

Barocaloric effects─thermal changes in a material induced by applied hydrostatic pressure─offer promise for creating solid-state refrigerants as alternatives to conventional volatile refrigerants. To enable efficient and scalable barocaloric cooling, materials that undergo high-entropy, reversible phase transitions in the solid state in response to a small change in pressure are needed. Here, we report that pressure-induced spin-crossover (SCO) transitions in the molecular iron(II) complex Fe[HB(tz)3]2 (HB(tz)3- = bis[hydrotris(1,2,4-triazol-1-yl)borate]) drive giant and reversible barocaloric effects at easily accessible pressures. Specifically, high-pressure calorimetry and powder X-ray diffraction studies reveal that pressure shifts as low as 10 bar reversibly induce nonzero isothermal entropy changes, and a pressure shift of 150 bar reversibly induces a large isothermal entropy change (>90 J kg-1 K-1) and adiabatic temperature change (>2 K). Moreover, we demonstrate that the thermodynamics of the SCO transition can be fine-tuned through systematic deuteration of the tris(triazolyl)borate ligand. These results provide new insights into pressure-induced SCO transitions and further establish SCO materials as promising barocaloric materials.

8.
Anesth Pain Med (Seoul) ; 16(1): 75-80, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33530679

RESUMO

BACKGROUND: Hereditary angioedema (HAE) is a rare disease caused by the deficiency of C1 esterase inhibitor. HAE has a risk of life-threatening complications such as capillary leak syndrome (CLS) and disseminated intravascular coagulation (DIC). CASE: A 42-year-old male patient with HAE presented for deceased-donor kidney transplantation. Prophylactic fresh frozen plasma (FFP) was given before surgery because of the risk of edema development. With careful management during anesthesia, there were no problems during surgery. However, generalized edema, hypotension, hypoalbuminemia, massive drainage of serosanguineous fluids from the intraabdominal space, and DIC occurred on the day after surgery. CLS was suspected and sustained hypotension with generalized edema became worse despite treatment with albumin, danazol, FFP, and vasoactive drugs. The patient's condition worsened despite intensive care and he died due to shock. CONCLUSIONS: The anesthesiologist should prepare for the critical complications of HAE and prepare the appropriate treatment options.

9.
Anesth Pain Med (Seoul) ; 15(4): 478-485, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33329852

RESUMO

BACKGROUND: Cimifugin is one of the components of the root of Saposhnikovia divaricata. The extract derived from S. divaricata is traditionally used as an analgesic. This study was conducted to evaluate the analgesic effect of intrathecal cimifugin in the formalin test. METHODS: Male Sprague-Dawley rats (n = 20) were randomized into four groups for intrathecal administration of 70% dimethylsulfoxide and various doses of cimifugin (100 µg, 300 µg, and 1,000 µg). The typical flinch response after the injection of 5% formalin into the hind paw was assessed in two distinct phases: phase 1 until 10 min, and phase 2 from 10 min to 60 min. ED50 values were calculated via linear regression. RESULTS: Intrathecal cimifugin significantly reduced the flinch response in both phases of the formalin test. Significant antinociceptive effects of cimifugin were found with the dose of 300 µg in phase 1 and the dose of 100 µg in phase 2. The ED50 value (95% confidence intervals) of intrathecal cimifugin was 696.1 (360.8-1,342.8) µg during phase 1 and 1,242.8 (42.0-48,292.5) µg during phase 2. CONCLUSIONS: Intrathecal cimifugin has an antinociceptive effect against formalin-induced pain. Cimifugin has an anti-inflammatory effect at low concentrations, and non-inflammatory analgesic effect at higher concentrations.

10.
Sci Adv ; 6(35): eabb3348, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32923638

RESUMO

The lack of a scalable nanoparticle-based computing architecture severely limits the potential and use of nanoparticles for manipulating and processing information with molecular computing schemes. Inspired by the von Neumann architecture (VNA), in which multiple programs can be operated without restructuring the computer, we realized the nanoparticle-based VNA (NVNA) on a lipid chip for multiple executions of arbitrary molecular logic operations in the single chip without refabrication. In this system, nanoparticles on a lipid chip function as the hardware that features memory, processors, and output units, and DNA strands are used as the software to provide molecular instructions for the facile programming of logic circuits. NVNA enables a group of nanoparticles to form a feed-forward neural network, a perceptron, which implements functionally complete Boolean logic operations, and provides a programmable, resettable, scalable computing architecture and circuit board to form nanoparticle neural networks and make logical decisions.

11.
Commun Biol ; 3(1): 420, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32747637

RESUMO

While technologies for measuring transcriptomes in single cells have matured, methods for measuring proteins and their post-translational modification (PTM) states in single cells are still being actively developed. Unlike nucleic acids, proteins cannot be amplified, making detection of minute quantities from single cells difficult. Here, we develop a strategy to detect targeted protein and its PTM isoforms in single cells. We barcode the proteins from single cells by tagging them with oligonucleotides, pool barcoded cells together, run bulk gel electrophoresis to separate protein and its PTM isoform and quantify their abundances by sequencing the oligonucleotides associated with each protein species. We used this strategy, iDentification and qUantification sEparaTion (DUET), to measure histone protein H2B and its monoubiquitination isoform, H2Bub, in single yeast cells. Our results revealed the heterogeneities of H2B ubiquitination levels in single cells from different cell-cycle stages, which is obscured in ensemble measurements.


Assuntos
Histonas/genética , Processamento de Proteína Pós-Traducional/genética , Proteínas/isolamento & purificação , Análise de Célula Única , Histonas/isolamento & purificação , Isoformas de Proteínas/genética , Isoformas de Proteínas/isolamento & purificação , Proteínas/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/isolamento & purificação , Ubiquitinação/genética
12.
Commun Biol ; 3(1): 463, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811971

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

13.
Acc Chem Res ; 52(10): 2793-2805, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31553568

RESUMO

Plasmonic nanoparticles are widely exploited in diverse bioapplications ranging from therapeutics to biosensing and biocomputing because of their strong and tunable light-matter interactions, facile and versatile chemical/biological ligand modifications, and biocompatibility. With the rapid growth of nanobiotechnology, understanding dynamic interactions between nanoparticles and biological systems at the molecular or single-particle level is becoming increasingly important for interrogating biological systems with functional nanostructures and for developing nanoparticle-based biosensors and therapeutic agents. Therefore, significant efforts have been devoted to precisely design and create nano-bio interfaces by manipulating the nanoparticles' size, shape, and surface ligand interactions with complex biological systems to maximize their performance and avoid unwanted responses, such as their agglomeration and cytotoxicity. However, investigating physicochemical interactions at the nano-bio interfaces in a quantitative and controllable manner remains challenging, as the interfaces involve highly complex networks between nanoparticles, biomolecules, and cells across multiple scales, each with a myriad of different chemical and biological interactions. A lipid bilayer is a membrane made of two layers of lipid molecules that forms a barrier around cells and plays structural and functional roles in diverse biological processes because they incorporate and present functional molecules (such as membrane proteins) with lateral fluidity. Plasmonic nanoparticles conjugated on lipid membranes provide reliable analytical labels and functional moieties that allow for studying and manipulating interactions between nanoparticles and molecules with single-particle resolution; they also serve as efficient tools for applying optical, mechanical, and thermal stimuli to biological systems, which stem from plasmonic properties. Recently, new opportunities have emerged by interfacing nanoparticle-modified lipid bilayers (NLBs) with complex systems such as molecular circuits and living systems. In this Account, we briefly review how plasmonic properties can be beneficially harnessed on lipid bilayer membranes to investigate the structures and functions of cellular membranes and to develop new platforms for biomedical applications. In particular, we discuss the versatility of supported lipid bilayers (SLBs), which are planar lipid bilayers on hydrophilic substrates, as dynamic biomaterials that provide lateral fluidity and cell membrane-like environments. We then summarize our efforts to create a quantitative analytical platform utilizing nanoparticles as active building blocks and SLBs as integrative substrates. Through this bottom-up approach, various functionalized nanoparticles have been introduced onto lipid bilayers to render nanoparticle-nanoparticle, nanoparticle-lipid bilayer, and biomolecule-lipid bilayer interfaces programmable. Our system provides a new class of tools for studying thermodynamics and kinetics in complex networks of nanostructures and for realizing unique applications in biosensing and biocomputing.


Assuntos
Membrana Celular , Bicamadas Lipídicas , Nanopartículas , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Membrana Celular/química , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo
14.
J Am Chem Soc ; 141(35): 13734-13738, 2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-31430138

RESUMO

Targeting small-molecule fluorescent indicators using genetically encoded protein tags yields new hybrid sensors for biological imaging. Optimization of such systems requires redesign of the synthetic indicator to allow cell-specific targeting without compromising the photophysical properties or cellular performance of the small-molecule probe. We developed a bright and sensitive Ca2+ indicator by systematically exploring the relative configuration of dye and chelator, which can be targeted using the HaloTag self-labeling tag system. Our "isomeric tuning" approach is generalizable, yielding a far-red targetable indicator to visualize Ca2+ fluxes in the primary cilium.

15.
Small ; 15(26): e1900998, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31026121

RESUMO

Biocomputation is the algorithmic manipulation of biomolecules. Nanostructures, most notably DNA nanostructures and nanoparticles, become active substrates for biocomputation when modified with stimuli-responsive, programmable biomolecular ligands. This approach-biocomputing with nanostructures ("nano-bio computing")-allows autonomous control of matter and information at the nanoscale; their dynamic assemblies and beneficial properties can be directed without human intervention. Recently, lipid bilayers interfaced with nanostructures have emerged as a new biocomputing platform. This new nano-bio interface, which exploits lipid bilayers as a chemical circuit board for information processing, offers a unique reaction space for realizing nanostructure-based computation at a previously unexplored dimension. In this Concept, recent advances in nano-bio computing are briefly reviewed and the newly emerging concept of biocomputing with nanostructures on lipid bilayers is introduced.


Assuntos
DNA/química , Bicamadas Lipídicas/química , Nanoestruturas/química , Nanopartículas/química , Nanotecnologia/métodos
16.
Sci Adv ; 5(2): eaau2124, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30801008

RESUMO

Using nanoparticles as substrates for computation enables algorithmic and autonomous controls of their unique and beneficial properties. However, scalable architecture for nanoparticle-based computing systems is lacking. Here, we report a platform for constructing nanoparticle logic gates and circuits at the single-particle level on a supported lipid bilayer. Our "lipid nanotablet" platform, inspired by cellular membranes that are exploited to compartmentalize and control signaling networks, uses a lipid bilayer as a chemical circuit board and nanoparticles as computational units. On a lipid nanotablet, a single-nanoparticle logic gate senses molecules in solution as inputs and triggers particle assembly or disassembly as an output. We demonstrate a set of Boolean logic operations, fan-in/fan-out of logic gates, and a combinational logic circuit such as a multiplexer. We envisage that our approach to modularly implement nanoparticle circuits on a lipid bilayer will create new paradigms and opportunities in molecular computing, nanoparticle circuits, and systems nanoscience.


Assuntos
Lipídeos/química , Modelos Teóricos , Nanopartículas/química , Bicamadas Lipídicas/química , Nanotecnologia
17.
Mol Cells ; 42(1): 96, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30622232

RESUMO

[This corrects the article on p. 439 in vol. 39.].

18.
J Am Chem Soc ; 139(9): 3558-3566, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-28181801

RESUMO

Multiplexed real-time analysis on multiple interacting molecules and particles is needed to obtain information on binding patterns between multiple ligands and receptors, specificity of bond formations, and interacting pairs in a complex medium, often found in chemical and biological systems, and difference in binding affinity and kinetics for different binding pairs in one solution. In particular, multiplexed profiling of microRNA (miRNA) in a reliable, quantitative manner is of great demand for the use of miRNA in cell biology, biosensing, and clinical diagnostic applications, and accurate diagnosis of cancers with miRNA is not possible without detecting multiple miRNA sequences in a highly specific manner. Here, we report a multiplexed molecular detection strategy with optokinetically (OK) coded nanoprobes (NPs) that show high photostability, distinct optical signals, and dynamic behaviors on a supported lipid bilayer (SLB) (OK-NLB assay). Metal NPs with three distinct dark-field light scattering signals [red (R), green (G), and blue (B)] and three different target miRNA half-complements were tethered to a two dimensionally fluidic SLB with mobile (M) or immobile (I) state. In situ single-particle monitoring and normalized RGB analysis of the optokinetically combinatorial assemblies among three M-NPs and three I-NPs with dark-field microscopy (DFM) allow for differentiating and quantifying 9 different miRNA targets in one sample. The OK-NP-based assay enables simultaneous detection of multiple miRNA targets in a highly quantitative, specific manner within 1 h and can be potentially used for diagnosis of different cancer types. We validated the OK-NLB assay with single-base mismatched experiments and HeLa cell-extracted total RNA samples by comparing the assay results to the quantitative reverse transcription polymerase chain reaction (qRT-PCR) results.


Assuntos
Corantes Fluorescentes/química , MicroRNAs/análise , MicroRNAs/química , Nanoestruturas/química , Células HeLa , Humanos , Cinética , Bicamadas Lipídicas/química , MicroRNAs/genética , MicroRNAs/isolamento & purificação , Tamanho da Partícula , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Propriedades de Superfície , Células Tumorais Cultivadas
19.
Mol Cells ; 39(6): 439-46, 2016 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-27239813

RESUMO

Clearing and labeling techniques for large-scale biological tissues enable simultaneous extraction of molecular and structural information with minimal disassembly of the sample, facilitating the integration of molecular, cellular and systems biology across different scales. Recent years have witnessed an explosive increase in the number of such methods and their applications, reflecting heightened interest in organ-wide clearing and labeling across many fields of biology and medicine. In this review, we provide an overview and comparison of existing clearing and labeling techniques and discuss challenges and opportunities in the investigations of large-scale biological systems.


Assuntos
Imagem Óptica/métodos , Biologia de Sistemas/métodos , Imageamento Tridimensional/métodos , Microscopia Confocal/métodos , Coloração e Rotulagem
20.
Mar Pollut Bull ; 82(1-2): 208-20, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24655946

RESUMO

In order to detect the early impact of the Hebei Spirit oil spill on the shallow subtidal macrozoobenthic communities, macrobenthic fauna were collected seasonally for 3 years. The alkylated PAHs concentrations within sediments near Mallipo beach remained as high as 129 ng g(-)(1) DW one month after the oil spill, but the concentration decreased below the background level thereafter. The number of species and density decreased in 4 months compared to those before the oil spill. An opportunistic polychaete, Prionospio paradisea, occurred as a dominant species at subtidal area near Mallipo beach in 10 months after the oil spill. Any mass mortality of amphipods and any clear dominance of opportunistic species were not detected except for the stations near Mallipo and Hagampo beaches. The macrobenthic communities at the shallow subtidal stations seemed to have a relatively stable faunal composition, even not fully recovered, in 3 years after the Hebei Spirit oil spill.


Assuntos
Organismos Aquáticos/fisiologia , Biodiversidade , Sedimentos Geológicos/química , Invertebrados/fisiologia , Poluição por Petróleo/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/análise , Animais , Organismos Aquáticos/efeitos dos fármacos , Invertebrados/efeitos dos fármacos , Poliquetos/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Densidade Demográfica , República da Coreia , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
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