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1.
Curr Issues Mol Biol ; 46(9): 10545-10569, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39329977

RESUMEN

The study aims to investigate the effects of curcumin on radiation/chemotherapy-induced oral mucositis (R/CIOM) and preliminarily explore its mechanism. Randomized controlled trials were identified from the PubMed, Embase, Web of Science, Cochrane Library, Medline, and Google Scholar databases. RevMan 5.4 was used for statistical analysis to calculate the combined risk ratios (RRs). The mechanism was analyzed through network pharmacology, molecular docking, and a molecular dynamics simulation. The targets of curcumin were collected in HERB, PharmMapper, Targetnet, Swiss Target Prediction, and SuperPred. OMIM, GeneCards, and Disgenet were used to collect relevant targets for R/CIOM. Cytoscape software 3.8.0 was used to construct the component-target-pathway network. Protein-Protein Interaction (PPI) networks were constructed using the STRING database. GO and KEGG enrichment analyses were performed by Metascape. AutoDock Vina 4.2 software was used for molecular docking. The molecular dynamics simulation was performed by Gromacs v2022.03. It is found that 12 studies involving 565 patients were included. Meta-analyses showed that curcumin reduced the incidence of severe R/CIOM (RR 0.42 [0.24, 0.75]) and the mean severity of R/CIOM (MD -0.93 [-1.34, -0.52]). Eleven core target genes were identified in the treatment of R/CIOM with curcumin. The results of molecular docking and the molecular dynamics simulation showed that curcumin had strong binding energy and stability with target proteins including MAPK3, SRC, and TNF. Overall, these findings suggest curcumin can effectively improve severe R/CIOM, perhaps by affecting MAPK3, SRC, and TNF.

2.
ACS Appl Mater Interfaces ; 16(38): 50905-50915, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39269847

RESUMEN

CoSb3-based skutterudites have great potential as midtemperature thermoelectric (TE) materials due to their low cost and excellent electrical and mechanical properties. Their application, however, is limited by the high thermal conductivity and the degradation of TE performance at elevated temperatures, attributed to the adverse effects of bipolar diffusion. Herein, a series of SeyCo4Sb12-xTex compounds were successfully synthesized by combining a solid-state reaction and spark plasma sintering techniques to mitigate these challenges. It was found that doping Te at the Sb sites effectively enhanced the carrier concentration and suppressed the bipolar effect to obtain a superior power factor of ∼43 µW cm-1 K-2. Furthermore, due to the low resonant frequency of Se, filling voids of CoSb3 with Se achieved a low lattice thermal conductivity of 1.55 W m-1 K-1. Nevertheless, Se filling introduced additional holes, reducing the carrier concentration without a significant detriment of the carrier mobility. As a result, a maximum figure of merit of 1.23 was achieved for Se0.1Co4Sb11.55Te0.45 at 773 K. This work provides a valuable guidance for selecting appropriate filling and doping components to achieve synergistic optimization of the acoustics and electronics of CoSb3-based skutterudites.

3.
BMC Microbiol ; 24(1): 238, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961393

RESUMEN

OBJECTIVES: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is extensively employed for the identification of filamentous fungi on MALDI Biotyper (Bruker Daltonics) and Vitek MS (biomerieux), but the performance of fungi identification on new EXS2600 (Zybio) is still unknow. Our study aims to evaluate the new EXS2600 system's (Zybio) ability to rapidly identify filamentous fungi and determine its effect on turnaround time (TAT) in our laboratory. METHODS: We tested 117 filamentous fungi using two pretreatment methods: the formic acid sandwich (FA-sandwich) and a commercial mold extraction kit (MEK, Zybio). All isolates were confirmed via sequence analysis. Laboratory data were extracted from our laboratory information system over two 9-month periods: pre-EXS (April to December 2022) and post-EXS (April to December 2023), respectively. RESULTS: The total correct identification (at the species, genus, or complex/group level) rate of fungi was high, FA-sandwich (95.73%, 112/117), followed by MEK (94.02%, 110/117). Excluding 6 isolates not in the database, species-level identification accuracy was 92.79% (103/111) for FA-sandwich and 91.89% (102/111) for MEK; genus-level accuracy was 97.29% (108/111) and 96.39% (107/111), respectively. Both methods attained a 100% correct identification rate for Aspergillus, Lichtheimia, Rhizopus Mucor and Talaromyces species, and were able to differentiate between Fusarium verticillioides and Fusarium proliferatum within the Fusarium fujikuroi species complex. Notably, high confidence was observed in the species-level identification of uncommon fungi such as Trichothecium roseum and Geotrichum candidum. The TAT for all positive cultures decreased from pre EXS2600 to post (108.379 VS 102.438, P < 0.05), and the TAT for tissue decreased most (451.538 VS 222.304, P < 0.001). CONCLUSIONS: The FA-sandwich method is more efficient and accurate for identifying filamentous fungi with EXS2600 than the MEK. Our study firstly evaluated the performance of fungi identification on EXS2600 and showed it is suitable for clinical microbiology laboratories use.


Asunto(s)
Formiatos , Hongos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Hongos/clasificación , Hongos/aislamiento & purificación , Hongos/química , Hongos/genética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Formiatos/química
4.
Proc Natl Acad Sci U S A ; 121(19): e2317703121, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38687792

RESUMEN

Fluorescence labeling of chemically fixed specimens, especially immunolabeling, plays a vital role in super-resolution imaging as it offers a convenient way to visualize cellular structures like mitochondria or the distribution of biomolecules with high detail. Despite the development of various distinct probes that enable super-resolved stimulated emission depletion (STED) imaging of mitochondria in live cells, most of these membrane-potential-dependent fluorophores cannot be retained well in mitochondria after chemical fixation. This lack of suitable mitochondrial probes has limited STED imaging of mitochondria to live cell samples. In this study, we introduce a mitochondria-specific probe, PK Mito Orange FX (PKMO FX), which features a fixation-driven cross-linking motif and accumulates in the mitochondrial inner membrane. It exhibits high fluorescence retention after chemical fixation and efficient depletion at 775 nm, enabling nanoscopic imaging both before and after aldehyde fixation. We demonstrate the compatibility of this probe with conventional immunolabeling and other strategies commonly used for fluorescence labeling of fixed samples. Moreover, we show that PKMO FX facilitates correlative super-resolution light and electron microscopy, enabling the correlation of multicolor fluorescence images and transmission EM images via the characteristic mitochondrial pattern. Our probe further expands the mitochondrial toolkit for multimodal microscopy at nanometer resolutions.


Asunto(s)
Aldehídos , Colorantes Fluorescentes , Microscopía Fluorescente , Mitocondrias , Mitocondrias/metabolismo , Humanos , Colorantes Fluorescentes/química , Aldehídos/metabolismo , Aldehídos/química , Microscopía Fluorescente/métodos , Células HeLa , Reactivos de Enlaces Cruzados/química , Animales , Membranas Mitocondriales/metabolismo
5.
Curr Opin Chem Biol ; 79: 102439, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38432145

RESUMEN

Fluorescent dyes synergize with advanced microscopy for researchers to investigate the location and dynamic processes of biomacromolecules with high spatial and temporal resolution. However, the instability of fluorescent dyes, including photobleaching and photoconversion, represent fundamental limits for super-resolution and time-lapse imaging. In this review, we discuss the latest advances in improving the photostability of fluorescent dyes. We summarize the primary photobleaching processes of cyanine and rhodamine dyes and highlight a range of strategies developed in recent years to strengthen these fluorophores. Additionally, we discuss the influence of protein microenvironments and labeling methods on the photostability of fluorophores. We aim to inspire next-generation robust and bright fluorophores that ultimately enable the routine practice of time-lapse super-resolution imaging of live cells.


Asunto(s)
Colorantes Fluorescentes , Proteínas , Colorantes Fluorescentes/metabolismo , Fotoblanqueo , Microscopía Fluorescente/métodos , Rodaminas
6.
ACS Chem Biol ; 19(4): 916-925, 2024 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-38491942

RESUMEN

Bispecific antibodies (BsAbs) represent an emerging class of biologics that can recognize two different antigens or epitopes. T-cell engagers (TcEs) bind two targets in trans on the cell surface of the effector and target cell to induce proximal immune effects, opening exciting windows for immunotherapies. To date, the engineering of BsAbs has been mainly focused on tuning the molecular weight and valency. However, the effects of spatial factors on the biological functions of BsAbs have been less explored due to the lack of biochemical methods to precisely manipulate protein geometry. Here, we studied the geometric effects of the TcEs. First, by genetically inserting rigidly designed ankyrin repeat proteins into TcEs, we revealed that the efficacy progressively decreased as the spacer distance of the two binding domains increased. Then, we constructed 26 pairs of TcEs with the same size but varying orientations using click chemistry-mediated conjugation at different mutation sites. We found that linear ligation sites play a minor role in modulating cell-killing efficacy. Next, we rendered the TcEs' advanced topology by cyclization chemistry using the SpyTag/SpyCatcher pair or sortase ligation approaches. Cyclized TcEs were generally more potent than their linear counterparts. Particularly, sortase A cyclized TcEs, bearing a minimal tagging motif, exhibited better cell-killing efficacy in vitro and improved stability both in vitro and in vivo compared to the linear TcE. This work combines modern bioconjugation chemistry and protein engineering tools for antibody engineering, shedding light on the elusive spatial factors of BsAbs functionality.


Asunto(s)
Anticuerpos Biespecíficos , Linfocitos T , Anticuerpos Biespecíficos/genética , Anticuerpos Biespecíficos/uso terapéutico , Anticuerpos Biespecíficos/química , Química Clic , Ingeniería de Proteínas/métodos , Proteínas , Linfocitos T/inmunología , Humanos
7.
Small ; 20(28): e2311340, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38319021

RESUMEN

Carrier regulation has proven to be an effective approach for optimizing the thermoelectric performance of materials. One common method to adjust the carrier concentration is through element doping. In the case of AgCuTe-based materials, it tends to form with cation vacancies, resulting in a high hole concentration and complex phase composition at low temperatures, which also hinders material stability. However, this also offers additional opportunities to manipulate the carrier concentration. In this study, the improved performance of AgCuTe through indium doping is reported, which leads to a reduction in hole concentration. In combination with a significant increase in the effective mass of the carriers, the enhanced Seebeck coefficient is also realized. Particularly, a notable improvement in power factor is observed in the hexagonal phase near room temperature. Furthermore, a lower electron thermal conductivity is achieved, contributing to an average figure of merit value of ≈1.21 (between 523 and 723 K). Additionally, the presence of indium inhibits the formation of the second phase and ensures a homogeneous phase distribution, which reduces the instability arising from phase transition. This work significantly enhances the potential of AgCuTe-based materials for low to medium-temperature applications.

8.
Updates Surg ; 76(4): 1183-1194, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38396193

RESUMEN

Antibiotics Prophylaxis to prevent capsular contracture in prosthesis-based breast surgery is common in clinical practice. However, there is currently a dearth of high-quality evidence concerning the effectiveness of antibiotic usage in this field. To identify all pertinent studies prior to January 2023, a comprehensive literature search was conducted in the PubMed, Embase, Web of Science, Cochrane Library, and Medline databases. The extracted data was then subjected to meta-analysis. Fourteen studies were retained in the analysis. According to the results, perioperative antibiotic prophylaxis did not reduce the risk of capsular contracture (RR 1.15, 95% CI 0.82-1.59, p = 0.55) or surgical-site infection (RD 0.01, 95% CI - 0.01 to 0.03, p = 0.59) compared to nonantibiotic prophylaxis. There was no statistically significant difference between extended antibiotic prophylaxis and perioperative antibiotic prophylaxis in terms of preventing capsular contracture, whether calculated by patient numbers (RD 0.01, 95% CI - 0.01 to 0.02, p = 0.87) or by total procedures (RD 0.00, 95% CI - 0.00 to 0.01, p = 0.88), or controlling surgical-site infection (RR 1.05, 95% CI 0.77-1.44, p = 0.27). Additionally, topical antibiotic irrigation did not decrease the risk of infection (RR 0.61, 95% CI 0.34-1.08, p = 0.29) and capsular contracture, regardless of patient number (RR 0.41, 95% CI 0.27-0.63, p = 0.18) or total number of procedures (RR 1.29, 95% CI 0.73-2.28, p < 0.01). Current evidence revealed that both systemic and topical antibiotic prophylaxis may not provide benefits in preventing capsular contracture in prosthesis-based breast surgery. When the occurrence of surgical-site infections is minimized to the greatest extent, the administration of additional antibiotics for reducing capsular contracture should be carefully and judiciously considered.


Asunto(s)
Profilaxis Antibiótica , Implantes de Mama , Contractura Capsular en Implantes , Infección de la Herida Quirúrgica , Humanos , Profilaxis Antibiótica/métodos , Femenino , Contractura Capsular en Implantes/prevención & control , Contractura Capsular en Implantes/etiología , Infección de la Herida Quirúrgica/prevención & control , Infección de la Herida Quirúrgica/etiología , Implantes de Mama/efectos adversos , Implantación de Mama/efectos adversos , Implantación de Mama/métodos , Resultado del Tratamiento , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico
9.
Nat Metab ; 6(2): 238-253, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38278946

RESUMEN

Biphasic glucose-stimulated insulin secretion (GSIS) is essential for blood glucose regulation, but a mechanistic model incorporating the recently identified islet ß cell heterogeneity remains elusive. Here, we show that insulin secretion is spatially and dynamically heterogeneous across the islet. Using a zinc-based fluorophore with spinning-disc confocal microscopy, we reveal that approximately 40% of islet cells, which we call readily releasable ß cells (RRßs), are responsible for 80% of insulin exocytosis events. Although glucose up to 18.2 mM fully mobilized RRßs to release insulin synchronously (first phase), even higher glucose concentrations enhanced the sustained secretion from these cells (second phase). Release-incompetent ß cells show similarities to RRßs in glucose-evoked Ca2+ transients but exhibit Ca2+-exocytosis coupling deficiency. A decreased number of RRßs and their altered secretory ability are associated with impaired GSIS progression in ob/ob mice. Our data reveal functional heterogeneity at the level of exocytosis among ß cells and identify RRßs as a subpopulation of ß cells that make a disproportionally large contribution to biphasic GSIS from mouse islets.


Asunto(s)
Insulinas Bifásicas , Células Secretoras de Insulina , Ratones , Animales , Secreción de Insulina , Insulinas Bifásicas/metabolismo , Glucosa/farmacología , Glucosa/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Exocitosis/fisiología
10.
Small ; 20(12): e2307798, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37946398

RESUMEN

P-type Sb2Te3 has been recognized as a potential thermoelectric material for applications in low-medium temperature ranges. However, its inherent high carrier concentration and lattice thermal conductivity led to a relatively low ZT value, particularly around room temperature. This study addresses these limitations by leveraging high-energy ball milling and rapid hot-pressing techniques to substantially enhance the Seebeck coefficient and power factor of Sb2Te3, yielding a remarkable ZT value of 0.55 at 323 K due to the donor-like effect. Furthermore, the incorporation of Nb─Ag co-doping increases hole concentration, effectively suppressing intrinsic excitations ≈548 K while maintaining the favorable power factor. Simultaneously, the lattice thermal conductivity can be significantly reduced upon doping. As a result, the ZT values of Sb2Te3-based materials attain an impressive range of 0.5-0.6 at 323 K, representing an almost 100% improvement compared to previous research endeavors. Finally, the ZT value of Sb1.97Nb0.03Ag0.005Te3 escalates to 0.92 at 548 K with a record average ZT value (ZTavg) of 0.75 within the temperature range of 323-573 K. These achievements hold promising implications for advancing the viability of V-VI commercialized materials for low-medium temperature application.

11.
J Clin Pediatr Dent ; 47(6): 178-184, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37997250

RESUMEN

Low-angle skeletal class II malocclusions are often observed with sagittal and vertical developmental abnormalities of the mandible. Two-phase orthodontic treatment of functional orthopedic therapy combined with fixed correction is one of the most common methods to treat of skeletal class II malocclusions. This case report describes the two-phase orthodontic treatment of a patient with severe low-angle skeletal class II malocclusion. A Twin Block orthodontic appliance was used to improve mandibular growth, and the adjustment of the occlusal relationship using a fixed appliance after functional therapy. After treatment, a significant improvement was observed in the patient's facial appearance and occlusal relationship. Additionally, a 7-year follow-up confirmed the stability of the treatment results. Although a vertical facial growth direction is difficult to control, the Twin Block orthodontic appliance in adolescents might effectively improve the difference in the sagittal growth of the mandible. Whilst the growth pattern could not be fully controlled, the treatment significantly improved the patient's facial profile and occlusion.


Asunto(s)
Maloclusión Clase II de Angle , Maloclusión , Aparatos Ortodóncicos Funcionales , Adolescente , Humanos , Estudios de Seguimiento , Maloclusión Clase II de Angle/terapia , Atención Odontológica , Mandíbula , Resultado del Tratamiento , Cefalometría/métodos , Diseño de Aparato Ortodóncico
12.
Anal Chem ; 95(46): 16976-16986, 2023 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-37943785

RESUMEN

Carboxylic acids are central metabolites in bioenergetics, signal transduction, and post-translation protein regulation. However, the quantitative analysis of carboxylic acids as an indispensable part of metabolomics is prohibitively challenging, particularly in trace amounts of biosamples. Here we report a diazo-carboxyl/hydroxylamine-ketone double click derivatization method for the sensitive analysis of hydrophilic, low-molecular-weight carboxylic acids. In general, our method renders a 5- to 2000-fold higher response in mass spectrometry along with improved chromatographic separation. With this method, we presented the near-single-cell analysis of carboxylic acid metabolites in 10 mouse egg cells before and after fertilization. Malate, fumarate, and ß-hydroxybutyrate were found to decrease after fertilization. We also monitored the isotope labeling kinetics of carboxylic acids inside adherent cells cultured in 96-well plates during drug treatment. Finally, we applied this method to plasma or serum samples (5 µL) collected from mice and humans under pathological and physiological conditions. The double click derivatization method paves a way toward single-cell metabolomics and bedside diagnostics.


Asunto(s)
Ácidos Carboxílicos , Espectrometría de Masas en Tándem , Humanos , Animales , Ratones , Ácidos Carboxílicos/química , Espectrometría de Masas en Tándem/métodos , Metabolómica/métodos , Marcaje Isotópico/métodos
13.
Front Bioeng Biotechnol ; 11: 1089031, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37811379

RESUMEN

Microtia is a congenital deformity of the ear with an incidence of about 0.8-4.2 per 10,000 births. Total auricular reconstruction is the preferred treatment of microtia at present, and one of the core technologies is the preparation of cartilage scaffolds. Autologous costal cartilage is recognized as the best material source for constructing scaffold platforms. However, costal cartilage harvest can lead to donor-site injuries such as pneumothorax, postoperative pain, chest wall scar and deformity. Therefore, with the need of alternative to autologous cartilage, in vitro and in vivo studies of biomaterial scaffolds and cartilage tissue engineering have gradually become novel research hot points in auricular reconstruction research. Tissue-engineered cartilage possesses obvious advantages including non-rejection, minimally invasive or non-invasive, the potential of large-scale production to ensure sufficient donors and controllable morphology. Exploration and advancements of tissue-engineered cartilaginous framework are also emerging in aspects including three-dimensional biomaterial scaffolds, acquisition of seed cells and chondrocytes, 3D printing techniques, inducing factors for chondrogenesis and so on, which has greatly promoted the research process of biomaterial substitute. This review discussed the development, current application and research progress of cartilage tissue engineering in auricular reconstruction, particularly the usage and creation of biomaterial scaffolds. The development and selection of various types of seed cells and inducing factors to stimulate chondrogenic differentiation in auricular cartilage were also highlighted. There are still confronted challenges before the clinical application becomes widely available for patients, and its long-term effect remains to be evaluated. We hope to provide guidance for future research directions of biomaterials as an alternative to autologous cartilage in ear reconstruction, and finally benefit the transformation and clinical application of cartilage tissue engineering and biomaterials in microtia treatment.

14.
Front Cell Dev Biol ; 11: 1204050, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37564374

RESUMEN

Background: The treatment of microtia or acquired ear deformities by surgery is a significant challenge for plastic and ENT surgeons; one of the most difficult points is constructing the scaffold for auricular reconstruction. As a type of cell with multiple differentiation potentials, stem cells play an essential role in the construction of cartilage scaffolds, and therefore have received widespread attention in ear reconstructive research. Methods: A literature search was conducted for peer-reviewed articles between 2005 and 2023 with the following keywords: stem cells; auricular cartilage; ear cartilage; conchal cartilage; auricular reconstruction, regeneration, and reparation of chondrocytes; tissue engineering in the following databases: PubMed, MEDLINE, Cochrane, and Ovid. Results: Thirty-three research articles were finally selected and their main characteristics were summarized. Adipose-derived stem cells (ADSCs), bone marrow mesenchymal stem cells (BMMSCs), perichondrial stem/progenitor cells (PPCs), and cartilage stem/progenitor cells (CSPCs) were mainly used in chondrocyte regeneration. Injecting the stem cells into the cartilage niche directly, co-culturing the stem cells with the auricular cartilage cells, and inducing the cells in the chondrogenic medium in vitro were the main methods that have been demonstrated in the studies. The chondrogenic ability of these cells was observed in vitro, and they also maintained good elasticity and morphology after implantation in vivo for a period of time. Conclusion: ADSC, BMMSC, PPC, and CSPC were the main stem cells that have been researched in craniofacial cartilage reconstruction, the regenerative cartilage performed highly similar to normal cartilage, and the test of AGA and type II collagen content also proved the cartilage property of the neo-cartilage. However, stem cell reconstruction of the auricle is still in the initial stage of animal experiments, transplantation with such scaffolds in large animals is still lacking, and there is still a long way to go.

15.
BMC Microbiol ; 23(1): 228, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37608359

RESUMEN

BACKGROUND: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has revolutionized microbial identification. However, there is a lack of data on its performance in identifying filamentous fungi. The objective of our study was to evaluate the accuracy of the Autof ms1000 mass spectrometry for identifying filamentous fungi in the clinical microbiology laboratory. RESULTS: Among 106 samples tested using the Autof ms1000 system, 101 (95.28%) were identified at the genus or species level, and 81 (76.41%) were accurately identified at the species level. Additionally, we developed a new rapid formic acid extraction method with simple pretreatment for filamentous fungi that saved time and provided accurate results. CONCLUSIONS: The Autof ms1000 mass spectrometer proved to be a valuable tool for identifying filamentous fungi. However, upgrading the database is recommended for correctly identifying rare strains.


Asunto(s)
Hongos , Laboratorios , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Bases de Datos Factuales
16.
Proc Natl Acad Sci U S A ; 120(34): e2306950120, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37590412

RESUMEN

Hybrid voltage indicators (HVIs) are chemogenetic sensors that combines the superior photophysical properties of organic dyes and the genetic targetability of protein sensors to report transient membrane voltage changes. They exhibit boosted sensitivity in excitable cells such as neurons and cardiomyocytes. However, the voltage signals recorded during long-term imaging are severely diminished or distorted due to phototoxicity and photobleaching issues. To capture stable electrophysiological activities over a long time, we employ cyanine dyes conjugated with a cyclooctatetraene (COT) molecule as the fluorescence reporter of HVI. The resulting orange-emitting HVI-COT-Cy3 enables high-fidelity voltage imaging for up to 30 min in cultured primary neurons with a sensitivity of ~ -30% ΔF/F0 per action potential (AP). It also maximally preserves the signal of individual APs in cardiomyocytes. The far-red-emitting HVI-COT-Cy5 allows two-color voltage/calcium imaging with GCaMP6s in neurons and cardiomyocytes for 15 min. We leverage the HVI-COT series with reduced phototoxicity and photobleaching to evaluate the impact of drug candidates on the electrophysiology of excitable cells.


Asunto(s)
Dermatitis Fototóxica , Miocitos Cardíacos , Humanos , Neuronas , Diagnóstico por Imagen , Colorantes
17.
Cell Discov ; 9(1): 53, 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37280224

RESUMEN

The differentiation of pluripotent stem cells (PSCs) into diverse functional cell types provides a promising solution to support drug discovery, disease modeling, and regenerative medicine. However, functional cell differentiation is currently limited by the substantial line-to-line and batch-to-batch variabilities, which severely impede the progress of scientific research and the manufacturing of cell products. For instance, PSC-to-cardiomyocyte (CM) differentiation is vulnerable to inappropriate doses of CHIR99021 (CHIR) that are applied in the initial stage of mesoderm differentiation. Here, by harnessing live-cell bright-field imaging and machine learning (ML), we realize real-time cell recognition in the entire differentiation process, e.g., CMs, cardiac progenitor cells (CPCs), PSC clones, and even misdifferentiated cells. This enables non-invasive prediction of differentiation efficiency, purification of ML-recognized CMs and CPCs for reducing cell contamination, early assessment of the CHIR dose for correcting the misdifferentiation trajectory, and evaluation of initial PSC colonies for controlling the start point of differentiation, all of which provide a more invulnerable differentiation method with resistance to variability. Moreover, with the established ML models as a readout for the chemical screen, we identify a CDK8 inhibitor that can further improve the cell resistance to the overdose of CHIR. Together, this study indicates that artificial intelligence is able to guide and iteratively optimize PSC differentiation to achieve consistently high efficiency across cell lines and batches, providing a better understanding and rational modulation of the differentiation process for functional cell manufacturing in biomedical applications.

18.
Front Pharmacol ; 14: 1142003, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37342592

RESUMEN

Sodium-glucose co-transporter type 2 (SGLT 2, gliflozins) inhibitors are potent orally active drugs approved for managing type 2 diabetes. SGLT 2 inhibitors exert a glucose-lowering effect by suppressing sodium-glucose co-transporters 1 and 2 in the intestinal and kidney proximal tubules. In this study, we developed a physiologically based pharmacokinetic (PBPK) model and simulated the concentrations of ertugliflozin, empagliflozin, henagliflozin, and sotagliflozin in target tissues. We used the perfusion-limited model to illustrate the disposition of SGLT 2 inhibitors in vivo. The modeling parameters were obtained from the references. Simulated steady-state plasma concentration-time curves of the ertugliflozin, empagliflozin, henagliflozin, and sotagliflozin are similar to the clinically observed curves. The 90% prediction interval of simulated excretion of drugs in urine captured the observed data well. Furthermore, all corresponding model-predicted pharmacokinetic parameters fell within a 2-fold prediction error. At the approved doses, we estimated the effective concentrations in intestinal and kidney proximal tubules and calculated the inhibition ratio of SGLT transporters to differentiate the relative inhibition capacities of SGLT1 and 2 in each gliflozin. According to simulation results, four SGLT 2 inhibitors can nearly completely inhibit SGLT 2 transporter at the approved dosages. Sotagliflozin exhibited the highest inhibition activity on SGLT1, followed by ertugliflozin, empagliflozin, and henagliflozin, which showed a lower SGLT 1 inhibitory effect. The PBPK model successfully simulates the specific target tissue concentration that cannot be measured directly and quantifies the relative contribution toward SGLT 1 and 2 for each gliflozin.

19.
Sci China Life Sci ; 66(8): 1858-1868, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37129766

RESUMEN

Hypomyelination leukodystrophies constitute a group of heritable white matter disorders exhibiting defective myelin development. Initially identified as a lysosomal protein, the TMEM106B D252N mutant has recently been associated with hypomyelination. However, how lysosomal TMEM106B facilitates myelination and how the D252N mutation disrupts that process are poorly understood. We used superresolution Hessian structured illumination microscopy (Hessian-SIM) and spinning disc-confocal structured illumination microscopy (SD-SIM) to find that the wild-type TMEM106B protein is targeted to the plasma membrane, filopodia, and lysosomes in human oligodendrocytes. The D252N mutation reduces the size of lysosomes in oligodendrocytes and compromises lysosome changes upon starvation stress. Most importantly, we detected reductions in the length and number of filopodia in cells expressing the D252N mutant. PLP1 is the most abundant myelin protein that almost entirely colocalizes with TMEM106B, and coexpressing PLP1 with the D252N mutant readily rescues the lysosome and filopodia phenotypes of cells. Therefore, interactions between TMEM106B and PLP1 on the plasma membrane are essential for filopodia formation and myelination in oligodendrocytes, which may be sustained by the delivery of these proteins from lysosomes via exocytosis.


Asunto(s)
Proteínas del Tejido Nervioso , Seudópodos , Humanos , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Seudópodos/metabolismo , Oligodendroglía/metabolismo , Vaina de Mielina/metabolismo , Mutación , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo
20.
J Am Chem Soc ; 145(14): 7758-7762, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36995255

RESUMEN

The pursuit of better sensitivity has always been one of the central themes in Raman spectroscopy. Recently, all-far-field single-molecule Raman spectroscopy has been demonstrated by a novel hybrid spectroscopy that couples Raman scattering with fluorescence emission. However, such frequency-domain spectroscopy lacks efficient hyperspectral excitation methods and encounters intrinsic strong fluorescence backgrounds from electronic transitions, hindering its applications in advanced Raman spectroscopy and microscopy. Here we report the ultrafast time-domain spectroscopy counterpart named transient stimulated Raman excited fluorescence (T-SREF): excited by two successive broadband femtosecond pulse pairs (i.e., the pump and Stokes pulses) with time-delay scanning, strong vibrational wave packet interference is revealed on the time-domain fluorescence trace, resulting in background-free spectra of the corresponding Raman modes after the Fourier transform. T-SREF achieves background-free Raman spectra of electronic-coupled vibrational modes with sensitivity up to the level of a few molecules, which paves the way for supermultiplexed fluorescence detection and molecular dynamics sensing.

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