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1.
Cell ; 185(4): 672-689.e23, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35114111

RESUMO

ChRmine, a recently discovered pump-like cation-conducting channelrhodopsin, exhibits puzzling properties (large photocurrents, red-shifted spectrum, and extreme light sensitivity) that have created new opportunities in optogenetics. ChRmine and its homologs function as ion channels but, by primary sequence, more closely resemble ion pump rhodopsins; mechanisms for passive channel conduction in this family have remained mysterious. Here, we present the 2.0 Å resolution cryo-EM structure of ChRmine, revealing architectural features atypical for channelrhodopsins: trimeric assembly, a short transmembrane-helix 3, a twisting extracellular-loop 1, large vestibules within the monomer, and an opening at the trimer interface. We applied this structure to design three proteins (rsChRmine and hsChRmine, conferring further red-shifted and high-speed properties, respectively, and frChRmine, combining faster and more red-shifted performance) suitable for fundamental neuroscience opportunities. These results illuminate the conduction and gating of pump-like channelrhodopsins and point the way toward further structure-guided creation of channelrhodopsins for applications across biology.


Assuntos
Channelrhodopsins/química , Channelrhodopsins/metabolismo , Ativação do Canal Iônico , Animais , Channelrhodopsins/ultraestrutura , Microscopia Crioeletrônica , Feminino , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Modelos Moleculares , Optogenética , Filogenia , Ratos Sprague-Dawley , Bases de Schiff/química , Células Sf9 , Relação Estrutura-Atividade
2.
Adv Mater ; 34(14): e2108203, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35073597

RESUMO

Although neurotransmitters are key substances closely related to evaluating degenerative brain diseases as well as regulating essential functions in the body, many research efforts have not been focused on direct observation of such biochemical messengers, rather on monitoring relatively associated physical, mechanical, and electrophysiological parameters. Here, a bioresorbable silicon-based neurochemical analyzer incorporated with 2D transition metal dichalcogenides is introduced as a completely implantable brain-integrated system that can wirelessly monitor time-dynamic behaviors of dopamine and relevant parameters in a simultaneous mode. An extensive range of examinations of molybdenum/tungsten disulfide (MoS2 /WS2 ) nanosheets and catalytic iron nanoparticles (Fe NPs) highlights the underlying mechanisms of strong chemical and target-specific responses to the neurotransmitters, along with theoretical modeling tools. Systematic characterizations demonstrate reversible, stable, and long-term operational performances of the degradable bioelectronics with excellent sensitivity and selectivity over those of non-dissolvable counterparts. A complete set of in vivo experiments with comparative analysis using carbon-fiber electrodes illustrates the capability for potential use as a clinically accessible tool to associated neurodegenerative diseases.


Assuntos
Silício , Compostos de Tungstênio , Implantes Absorvíveis , Eletrodos , Silício/química , Sulfetos
3.
Orthop J Sports Med ; 10(1): 23259671211069960, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35071661

RESUMO

BACKGROUND: Anatomic anterior cruciate ligament reconstruction (ACLR) is preferred over nonanatomic ACLR. However, there is no consensus on which point the tunnels should be positioned among the broad anatomic footprints. PURPOSE/HYPOTHESIS: To identify the ideal combination of tibial and femoral tunnel positions according to the femoral and tibial footprints of the anteromedial (AM) and posterolateral (PL) anterior cruciate ligament bundles. It was hypothesized that patients with anteromedially positioned tunnels would have better clinical scores, knee joint stability, and graft signal intensity on follow-up magnetic resonance imaging (MRI) than those with posterolaterally positioned tunnels. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 119 patients who underwent isolated single-bundle ACLR with a hamstring autograft from July 2013 to September 2018 were retrospectively investigated. Included were patients with clinical scores and knee joint stability test results at 2-year follow-up and postoperative 3-dimensional computed tomography and 1-year postoperative MRI findings. The cohort was divided into 4 groups, named according to the bundle positions in the tibial and femoral tunnels: AM-AM (n = 33), AM-PL (n = 26), PL-AM (n = 29), and PL-PL (n = 31). RESULTS: There were no statistically significant differences among the 4 groups in preoperative demographic data or postoperative clinical scores (Lysholm, Tegner, and International Knee Documentation Committee subjective scores); knee joint stability (anterior drawer, Lachman, and pivot-shift tests and Telos stress radiographic measurement of the side-to-side difference in anterior tibial translation); graft signal intensity on follow-up MRI; or graft failure. CONCLUSION: No significant differences in clinical scores, knee joint stability, or graft signal intensity on follow-up MRI were identified between the patients with anteromedially and posterolaterally positioned tunnels.

4.
BMC Musculoskelet Disord ; 23(1): 32, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983471

RESUMO

BACKGROUND: This study aimed to evaluate the efficacy of viscosupplementation after arthroscopic partial meniscectomy. METHOD: A randomized controlled trial of 47 patients who underwent arthroscopic partial meniscectomy was conducted between March 2020 and March 2021. Patients were randomized into two groups: a viscosupplementation group (n = 23) and a control group (n = 24). A single-dose intraarticular hyaluronic acid injection was used as viscosupplementation. The 100 mm visual analogue scale (VAS) for pain assessment was measured at baseline and at 1 day, 2 weeks, 6 weeks, and 3 months post-surgery. The International Knee Documentation Committee (IKDC), Tegner, Lysholm, and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) scores and range of motion (ROM) of the knee were measured at baseline, 2 weeks, 6 weeks, and 3 months. RESULTS: The 100 mm VAS score for pain was significantly lower in the viscosupplementation group at 2 weeks post-surgery (27.5 mm vs. 40.7 mm, P = 0.047). ROM was significantly greater in the viscosupplementation group than in the control group at 2 weeks (131.5° vs. 121.0°, P = 0.044) post-surgery. No significant differences were observed in the IKDC or in the Tegner, Lysholm, and WOMAC scores between the two groups. CONCLUSIONS: Viscosupplementation after arthroscopic partial meniscectomy significantly reduced pain at 2 weeks post-surgery and improved ROM of the knee at 2 weeks post-surgery. There might be some benefits in terms of pain and functional recovery of viscosupplementation after arthroscopic surgery. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. TRIAL REGISTRATION: This randomized controlled trial was registered at cris.nih.go.kr # KCT0004921 .


Assuntos
Osteoartrite do Joelho , Viscossuplementação , Artroscopia , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Meniscectomia/efeitos adversos , Osteoartrite do Joelho/tratamento farmacológico , Osteoartrite do Joelho/cirurgia , Resultado do Tratamento
5.
Cell Rep ; 37(6): 109975, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34758317

RESUMO

Dopamine (DA) neurons in the ventral tier of the substantia nigra pars compacta (SNc) degenerate prominently in Parkinson's disease, while those in the dorsal tier are relatively spared. Defining the molecular, functional, and developmental characteristics of each SNc tier is crucial to understand their distinct susceptibility. We demonstrate that Sox6 expression distinguishes ventrally and dorsally biased DA neuron populations in the SNc. The Sox6+ population in the ventral SNc includes an Aldh1a1+ subset and is enriched in gene pathways that underpin vulnerability. Sox6+ neurons project to the dorsal striatum and show activity correlated with acceleration. Sox6- neurons project to the medial, ventral, and caudal striatum and respond to rewards. Moreover, we show that this adult division is encoded early in development. Overall, our work demonstrates a dual origin of the SNc that results in DA neuron cohorts with distinct molecular profiles, projections, and functions.


Assuntos
Corpo Estriado/patologia , Neurônios Dopaminérgicos/patologia , Regulação da Expressão Gênica no Desenvolvimento , Doença de Parkinson/patologia , Fatores de Transcrição SOXD/metabolismo , Fatores de Transcrição SOXD/fisiologia , Substância Negra/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Casos e Controles , Corpo Estriado/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Fatores de Transcrição SOXD/genética , Substância Negra/metabolismo , Área Tegmentar Ventral/metabolismo , Área Tegmentar Ventral/patologia
6.
Sci Adv ; 7(43): eabj3176, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34669464

RESUMO

Quantum confinement in transition metal dichalcogenides (TMDCs) enables the realization of deterministic single-photon emitters. The position and polarization control of single photons have been achieved via local strain engineering using nanostructures. However, most existing TMDC-based emitters are operated by optical pumping, while the emission sites in electrically pumped emitters are uncontrolled. Here, we demonstrate electrically driven single-photon emitters located at the positions where strains are induced by atomic force microscope indentation on a van der Waals heterostructure consisting of graphene, hexagonal boron nitride, and tungsten diselenide. The optical, electrical, and mechanical properties induced by the local strain gradient were systematically analyzed. The emission at the indentation sites exhibits photon antibunching behavior with a g(2)(0) value of ~0.3, intensity saturation, and a linearly cross-polarized doublet, at 4 kelvin. This robust spatial control of electrically driven single-photon emitters will pave the way for the practical implementation of integrated quantum light sources.

7.
Neuron ; 109(23): 3823-3837.e6, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624220

RESUMO

The lateral hypothalamic area (LHA) regulates feeding- and reward-related behavior, but because of its molecular and anatomical heterogeneity, the functions of defined neuronal populations are largely unclear. Glutamatergic neurons within the LHA (LHAVglut2) negatively regulate feeding and appetitive behavior. However, this population comprises transcriptionally distinct and functionally diverse neurons that project to diverse brain regions, including the lateral habenula (LHb) and ventral tegmental area (VTA). To resolve the function of distinct LHAVglut2 populations, we systematically compared projections to the LHb and VTA using viral tracing, single-cell sequencing, electrophysiology, and in vivo calcium imaging. LHAVglut2 neurons projecting to the LHb or VTA are anatomically, transcriptionally, electrophysiologically, and functionally distinct. While both populations encode appetitive and aversive stimuli, LHb projecting neurons are especially sensitive to satiety state and feeding hormones. These data illuminate the functional heterogeneity of LHAVglut2 neurons, suggesting that reward and aversion are differentially processed in divergent efferent pathways.


Assuntos
Habenula , Região Hipotalâmica Lateral , Ácido Glutâmico/metabolismo , Habenula/fisiologia , Região Hipotalâmica Lateral/fisiologia , Vias Neurais/fisiologia , Neurônios/fisiologia , Área Tegmentar Ventral/metabolismo
8.
Adv Sci (Weinh) ; 8(19): e2100640, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34363354

RESUMO

Noble metal-based surface-enhanced Raman spectroscopy (SERS) has enabled the simple and efficient detection of trace-amount molecules via significant electromagnetic enhancements at hot spots. However, the small Raman cross-section of various analytes forces the use of a Raman reporter for specific surface functionalization, which is time-consuming and limited to low-molecular-weight analytes. To tackle these issues, a hybrid SERS substrate utilizing Ag as plasmonic structures and GaN as charge transfer enhancement centers is presented. By the conformal printing of Ag nanowires onto GaN nanopillars, a highly sensitive SERS substrate with excellent uniformity can be fabricated. As a result, remarkable SERS performance with a substrate enhancement factor of 1.4 × 1011 at 10 fM for rhodamine 6G molecules with minimal spot variations can be realized. Furthermore, quantification and multiplexing capabilities without surface treatments are demonstrated by detecting harmful antibiotics in aqueous solutions. This work paves the way for the development of a highly sensitive SERS substrate by constructing complex metal-semiconductor architectures.


Assuntos
Antibacterianos/análise , Gálio/química , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Biopolímeros/química , Tamanho da Partícula , Prata , Propriedades de Superfície
9.
Sci Adv ; 7(13)2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33771864

RESUMO

Quantum wells (QWs), enabling effective exciton confinement and strong light-matter interaction, form an essential building block for quantum optoelectronics. For two-dimensional (2D) semiconductors, however, constructing the QWs is still challenging because suitable materials and fabrication techniques are lacking for bandgap engineering and indirect bandgap transitions occur at the multilayer. Here, we demonstrate an unexplored approach to fabricate atomic-layer-confined multiple QWs (MQWs) via monolithic bandgap engineering of transition metal dichalcogenides and van der Waals stacking. The WOX/WSe2 hetero-bilayer formed by monolithic oxidation of the WSe2 bilayer exhibited the type I band alignment, facilitating as a building block for MQWs. A superlinear enhancement of photoluminescence with increasing the number of QWs was achieved. Furthermore, quantum-confined radiative recombination in MQWs was verified by a large exciton binding energy of 193 meV and a short exciton lifetime of 170 ps. This work paves the way toward monolithic integration of band-engineered heterostructures for 2D quantum optoelectronics.

10.
Nano Lett ; 21(3): 1546-1554, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33502866

RESUMO

Single-photon emitters, the basic building blocks of quantum communication and information, have been developed using atomically thin transition metal dichalcogenides (TMDCs). Although the bandgap of TMDCs was spatially engineered in artificially created defects for single-photon emitters, it remains a challenge to precisely align the emitter's dipole moment to optical cavities for the Purcell enhancement. Here, we demonstrate position- and polarization-controlled single-photon emitters in monolayer WSe2. A tensile strain of ∼0.2% was applied to monolayer WSe2 by placing it onto a dielectric rod structure with a nanosized gap. Excitons were localized in the nanogap sites, resulting in the generation of linearly polarized single-photon emission with a g(2) of ∼0.1 at 4 K. Additionally, we measured the abrupt change in polarization of single photons with respect to the nanogap size. Our robust spatial and polarization control of emission provides an efficient way to demonstrate deterministic and scalable single-photon sources by integrating with nanocavities.

11.
Nat Biotechnol ; 39(2): 161-164, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33020604

RESUMO

Achieving temporally precise, noninvasive control over specific neural cell types in the deep brain would advance the study of nervous system function. Here we use the potent channelrhodopsin ChRmine to achieve transcranial photoactivation of defined neural circuits, including midbrain and brainstem structures, at unprecedented depths of up to 7 mm with millisecond precision. Using systemic viral delivery of ChRmine, we demonstrate behavioral modulation without surgery, enabling implant-free deep brain optogenetics.


Assuntos
Encéfalo/cirurgia , Optogenética , Animais , Encéfalo/efeitos da radiação , Luz , Masculino , Camundongos Endogâmicos C57BL , Neurônios/fisiologia , Neurônios/efeitos da radiação , Ratos , Área Tegmentar Ventral/fisiologia , Área Tegmentar Ventral/efeitos da radiação
12.
ACS Appl Mater Interfaces ; 13(1): 1245-1252, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33356110

RESUMO

Monolayer transition metal dichalcogenides (TMDs) are promising for optoelectronics because of their high optical quantum yield and strong light-matter interaction. In particular, the van der Waals (vdW) heterostructures consisting of monolayer TMDs sandwiched by large gap hexagonal boron nitride have shown great potential for novel optoelectronic devices. However, a complicated stacking process limits scalability and practical applications. Furthermore, even though lots of efforts, such as fabrication of vdW heterointerfaces, modification of the surface, and structural phase transition, have been devoted to preserve or modulate the properties of TMDs, high environmental sensitivity and damage-prone characteristics of TMDs make it difficult to achieve a controllable technique for surface/interface engineering. Here, we demonstrate a novel way to fabricate multiple two-dimensional (2D) vdW heterostructures consisting of alternately stacked MoS2 and MoOx with enhanced photoluminescence (PL). We directly oxidized multilayer MoS2 to a MoOx/1 L-MoS2 heterostructure with atomic layer precision through a customized oxygen plasma system. The monolayer MoS2 covered by MoOx showed an enhanced PL intensity 3.2 and 6.5 times higher in average than the as-exfoliated 1 L- and 2 L-MoS2 because of preserved crystallinity and compensated dedoping by MoOx. By using layer-by-layer oxidation and transfer processes, we fabricated the heterostructures of MoOx/MoS2/MoOx/MoS2, where the MoS2 monolayers are separated by MoOx. The heterostructures showed the multiplied PL intensity as the number of embedded MoS2 layers increases because of suppression of the nonradiative trion formation and interlayer decoupling between stacked MoS2 layers. Our work shows a novel way toward the fabrication of 2D material-based multiple vdW heterostructures and our layer-by-layer oxidation process is beneficial for the fabrication of high performance 2D optoelectronic devices.

13.
Cell Rep ; 32(9): 108094, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32877676

RESUMO

Ventral tegmental area (VTA) neurons play roles in reward and aversion. We recently discovered that the VTA has neurons that co-transmit glutamate and GABA (glutamate-GABA co-transmitting neurons), transmit glutamate without GABA (glutamate-transmitting neurons), or transmit GABA without glutamate (GABA-transmitting neurons). However, the functions of these VTA cell types in motivated behavior are unclear. To identify the functions of these VTA cell types, we combine recombinase mouse lines with INTRSECT2.0 vectors to selectively target these neurons. We find that VTA cell types have unique signaling patterns for reward, aversion, and learned cues. Whereas VTA glutamate-transmitting neurons signal cues predicting reward, VTA GABA-transmitting neurons signal cues predicting the absence of reward, and glutamate-GABA co-transmitting neurons signal rewarding and aversive outcomes without signaling learned cues related to those outcomes. Thus, we demonstrate that genetically defined subclasses of VTA glutamate and GABA neurons signal different aspects of motivated behavior.


Assuntos
Neurônios GABAérgicos/metabolismo , Ácido Glutâmico/metabolismo , Motivação/genética , Área Tegmentar Ventral/fisiopatologia , Animais , Humanos , Masculino , Camundongos , Transdução de Sinais
14.
Pharmaceuticals (Basel) ; 13(9)2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32906686

RESUMO

Because chemotherapeutic drugs are often associated with serious side effects, the central topic in modern drug delivery is maximizing the localization of drugs at the target while minimizing non-specific drug interactions at unwanted regions. To address this issue, biocompatible nanoparticles have been developed to enhance the drug half-life while minimizing the associated toxicity. Nevertheless, relying solely on the enhanced half-life and enhanced permeability and retention (EPR) effects has been ineffective, and designing stimulus-sensitive nanoparticles to introduce the precise control of drug release has been desired. In this paper, we introduce a pH-sensitive, reduced albumin nanoparticle in combination with focused ultrasound treatment. Not only did these nanoparticles have superior therapeutic efficacy and toxicity profiles when compared to the free drugs in xenograft mouse models, but we were also able to show that the albumin nanoparticles reported in this paper were more suitable than other types of non-reduced albumin nanoparticles as vehicles for drug delivery. As such, we believe that the albumin nanoparticles presented in this paper with desirable characteristics including the induction of strong anti-tumor response, precise control, and superior safety profiles hold strong potential for preclinical and clinical anticancer therapy.

15.
Clin Orthop Surg ; 12(2): 258-262, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32489550

RESUMO

The mainstream surgery for valgus-impacted femoral neck fractures (FNFs) is closed reduction and internal fixation under fluoroscopy. However, femoral neck shortening and anterior femoroacetabular impingement are common complications in healed valgus-impacted FNFs after in situ fixation. Some methods have been reported to prevent complications, but these techniques require the use of a transfixing guide wire that passes through the femoral head, which may cause articular cartilage damage. We introduce a simple reduction technique using one Steinmann pin (S-pin) for valgus-impacted FNFs without any interference of the femur head. A S-pin was placed percutaneously at the inferomedial margin of the fracture, and reduction was achieved by applying manual valgus force along the fracture line. By restoring the anatomical alignment, we confirmed the maximum contact area of the fracture and connection of the medial cortical buttress, so the risk of nonunion was also minimized.


Assuntos
Pinos Ortopédicos , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Neuron ; 107(5): 836-853.e11, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32574559

RESUMO

The resolution and dimensionality with which biologists can characterize cell types have expanded dramatically in recent years, and intersectional consideration of such features (e.g., multiple gene expression and anatomical parameters) is increasingly understood to be essential. At the same time, genetically targeted technology for writing in and reading out activity patterns for cells in living organisms has enabled causal investigation in physiology and behavior; however, cell-type-specific delivery of these tools (including microbial opsins for optogenetics and genetically encoded Ca2+ indicators) has thus far fallen short of versatile targeting to cells jointly defined by many individually selected features. Here, we develop a comprehensive intersectional targeting toolbox including 39 novel vectors for joint-feature-targeted delivery of 13 molecular payloads (including opsins, indicators, and fluorophores), systematic approaches for development and optimization of new intersectional tools, hardware for in vivo monitoring of expression dynamics, and the first versatile single-virus tools (Triplesect) that enable targeting of triply defined cell types.


Assuntos
Técnicas Genéticas , Neurônios , Optogenética , Animais , Dependovirus , Vetores Genéticos , Células HEK293 , Humanos
17.
Handchir Mikrochir Plast Chir ; 52(1): 18-24, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32135550

RESUMO

PURPOSE: The purpose of this study was to investigate and compare the clinical and radiological results of ORIF with inter-fragment screw or buttress plate fixation of acute PIP joint fracture dorsal dislocation. PATIENTS AND METHODS: Between January 2007 to December 2016, nineteen patients - 14 men and 5 women with an average age of 40.9 (19 to 64) years - were included in this study; 9 patients underwent small sized interfragmentary screw fixation and 10 patients underwent small buttress plating. The average follow-up period was 45.1 (13 to 78) months. Clinical assessment included measurement of range of motion (ROM) of the proximal and distal interphalangeal joint (PIP, DIP), grip and pinch strength, and pain with use of the Visual Analog Scale (VAS). At the postoperative X-ray, articular step off, gap, and degree of dorsal subluxation was measured, and maintenance of the reduction, fracture union, and the presence of degenerative changes were assessed. RESULTS: All patients achieved solid unions without instability. The overall average range of motion of PIP joint were from 9° to 85° (10-83° in the screw group, 8-87° in the plate group without significant difference). However, the screw group (average: 53°) presented more flexion in the distal interphalangeal joint than the plate group (average: 34°). Plate fixation can cause limited DIP flexion. Six of the ten patients from the plate group, underwent implant removal and two of these patients required PIP joint arthrolysis due to the PIP flexion contracture of more than 30°. Three of the nine patients in screw group underwent implant removal and two of the three patients required PIP joint arthrolysis. CONCLUSION: Mini plate and screw fixation of acute PIP joint fracture dorsal dislocation can achieve comparable favorable clinical and radiographic outcomes through stable fixation and early range of motion exercise. Screw fixation, if possible, is probably preferable to plate fixation because of better DIP joint ROM and lower incidence of hardware removal. If there is a need for plate fixation the use of a short plate is recommended to avoid joint stiffness.


Assuntos
Fratura-Luxação/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Luxações Articulares/cirurgia , Adulto , Feminino , Articulações dos Dedos/cirurgia , Fixação Interna de Fraturas , Humanos , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Resultado do Tratamento
18.
Science ; 367(6484): 1372-1376, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32193327

RESUMO

The structural and functional complexity of multicellular biological systems, such as the brain, are beyond the reach of human design or assembly capabilities. Cells in living organisms may be recruited to construct synthetic materials or structures if treated as anatomically defined compartments for specific chemistry, harnessing biology for the assembly of complex functional structures. By integrating engineered-enzyme targeting and polymer chemistry, we genetically instructed specific living neurons to guide chemical synthesis of electrically functional (conductive or insulating) polymers at the plasma membrane. Electrophysiological and behavioral analyses confirmed that rationally designed, genetically targeted assembly of functional polymers not only preserved neuronal viability but also achieved remodeling of membrane properties and modulated cell type-specific behaviors in freely moving animals. This approach may enable the creation of diverse, complex, and functional structures and materials within living systems.


Assuntos
Compostos de Anilina/química , Ascorbato Peroxidases/genética , Engenharia Genética , Neurônios/fisiologia , Nitrocompostos/química , Fenilenodiaminas/química , Polímeros/química , Potenciais de Ação , Animais , Ascorbato Peroxidases/metabolismo , Caenorhabditis elegans , Membrana Celular/metabolismo , Sobrevivência Celular , Células Cultivadas , Condutividade Elétrica , Células HEK293 , Hipocampo , Humanos , Potenciais da Membrana , Camundongos , Neurônios Motores/fisiologia , Células Musculares/fisiologia , Neurônios/enzimologia , Técnicas de Patch-Clamp , Polímeros/metabolismo , Ratos , Transdução Genética
19.
Nanotechnology ; 31(4): 045304, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31593938

RESUMO

Polarized ultraviolet (UV) emitters are essential for various applications, such as photoalignment devices for liquid crystals, high-resolution imaging devices, highly sensitive sensors, and steppers. To increase the high polarization ratio (PR) of a UV emitter, the grating period should be decreased than that of the visible emitter. However, the fabrication of the short period grating directly on UV emitters is still limited. In this study, we demonstrate that 200, 100, and 50 nm period aluminum (Al)-based wire-grid polarizers (WGPs) can be fabricated directly on UV emitters by a solvent-assisted nanotransfer process. The UV emitter with a grating period of 100 nm shows a PR of 84%, and an electroluminescence efficiency that is 22.5% and 48% higher than those of UV emitters with 50 nm and 200 nm period WGPs, respectively, due to the increased photon extraction efficiency (PEE). The higher PEE is attributed to the optical cavity property of the Al metal reflector with low light loss and the surface plasmon effect of the Al grating layer.

20.
Medicine (Baltimore) ; 98(51): e18374, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31860997

RESUMO

RATIONALE: Deposition of tophus is a common feature in chronic gout; however, signs and symptoms are not always well-pronounced in cases of uncommon sites. We report a rare case with a tophaceous tendonitis on the flexor hallucis longus (FHL) tendon with tarsal tunnel syndrome (TTS). This is the first surgical case of TTS by gouty tophi in FHL. PATIENT CONCERNS: A 55-year-old woman presented with a 6-month history of mild discomfort at the right foot, which gradually worsened in the past 3 weeks. The patient visited our outpatient clinic due to persistent and aggravating foot pain and swelling around the tarsal tunnel. DIAGNOSIS: The patient was diagnosed with hyperuricemia and diabetes mellitus with chronic kidney disease, and did not receive regular antigout treatments. Paresthesia was found along the distribution of medial and plantar nerve and tinel test was positive on tarsal tunnel. Biochemical examination showed she had raised serum uric acid (10.6 mg/dL) and decreased estimated glomerular filtration rate (69 mL/min/1.73 m). Conventional radiography examination showed negative pathology except soft tissue swelling. Magnetic resonance imaging revealed a fusiform mass within the FHL tendon and fluid collection around tarsal tunnel. INTERVENTIONS: Surgical exploration was performed to remove the mass. Inflammation fluid exploded out from FHL tendon sheath, which was later proven to have infiltration of monosodium urate crystal. Superficial dissection revealed a white chalky mass and posterior tibial nerve was significantly compressed by the tophus mass. OUTCOMES: The mass was removed and the symptoms were relieved at immediate postoperative period. LESSONS: A tophaceous tendonitis on FHL tendon can cause TTS and surgical decompression of the gout lesion can reduce the symptoms.


Assuntos
Gota/complicações , Síndrome do Túnel do Tarso/etiologia , Complicações do Diabetes , Feminino , Gota/diagnóstico , Gota/cirurgia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Parestesia/etiologia , Parestesia/cirurgia , Insuficiência Renal Crônica/complicações , Síndrome do Túnel do Tarso/cirurgia , Tendinopatia/etiologia , Tendinopatia/cirurgia , Tendões/diagnóstico por imagem
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