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1.
Nano Lett ; 24(25): 7732-7740, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38869233

RESUMO

Rechargeable lithium-ion batteries are integral to contemporary energy storage, yet current anode material systems struggle to meet the increasing demand for extended range capabilities. This work introduces a novel composite anode material composed of one-dimensional 2H-phase tin disulfide (SnS2) nanoribbons enclosed within cavities of single-walled carbon nanotubes (SnS2@SWCNTs), achieved through precise atomic engineering. Employing aberration-corrected transmission electron microscopy, we precisely elucidated the crystal structure of SnS2 within the confines of the SWCNTs. This deliberate design effectively addresses the inherent limitations of SnS2 as a lithium-ion anode material, including its low electrical conductivity, considerable volume expansion effects, and unstable solid electrolyte interface membrane. Testing confirmed that SnS2 transforms into the Li5Sn2 alloy phase after full lithiation and back to SnS2 after delithiation, showing excellent reversibility. The composite also benefits from edge effects, improving lithium storage through stronger binding and lower migration barriers, which were supported by calculations. This pioneering work advances high-performance anode materials for applications.

2.
J Am Chem Soc ; 146(9): 6231-6239, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38386884

RESUMO

Acquiring a deep insight into the electron transfer mechanism and applications of one-dimensional (1D) van der Waals heterostructures (vdWHs) has always been a significant challenge. Herein, through direct observation using aberration-corrected transmission electron microscopy (AC-TEM), we verify the stable formation of a high-quality 1D heterostructure composed of PbI2@single-walled carbon nanotubes (SWCNTs). The phenomenon of electron transfer between PbI2 and SWCNT is elucidated through spectroscopic investigations, including Raman and X-ray photoelectron spectroscopy (XPS). Electrochemical testing indicates the electron transfer and enduring stability of 1D PbI2 within SWCNTs. Moreover, leveraging the aforementioned electron transfer mechanism, we engineer self-powered photodetectors that exhibit exceptional photocurrent and a 3-order-of-magnitude switching ratio. Subsequently, we reveal its unique electron transfer behavior using Kelvin probe force microscopic (KPFM) tests. According to KPFM, the average surface potential of SWCNTs decreases by 80.6 mV after filling. Theoretical calculations illustrate a charge transfer of 0.02 e per unit cell. This work provides an effective strategy for the in-depth investigation and application of electron transfer in 1D vdWHs.

3.
BMC Med Res Methodol ; 24(1): 170, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107710

RESUMO

BACKGROUND: Wolbachia symbiosis in Aedes aegypti is an emerging biocontrol measure against dengue. However, assessing its real-world efficacy is challenging due to the non-randomised, field-based nature of most intervention studies. This research re-evaluates the spatial-temporal impact of Wolbachia interventions on dengue incidence using a large battery of quasi-experimental methods and assesses each method's validity. METHODS: A systematic search for Wolbachia intervention data was conducted via PUBMED. Efficacy was reassessed using commonly-used quasi-experimental approaches with extensive robustness checks, including geospatial placebo tests and a simulation study. Intervention efficacies across multiple study sites were computed using high-resolution aggregations to examine heterogeneities across sites and study periods. We further designed a stochastic simulation framework to assess the methods' ability to estimate intervention efficacies (IE). RESULTS: Wolbachia interventions in Singapore, Malaysia, and Brazil significantly decreased dengue incidence, with reductions ranging from 48.17% to 69.19%. IEs varied with location and duration. Malaysia showed increasing efficacy over time, while Brazil exhibited initial success with subsequent decline, hinting at operational challenges. Singapore's strategy was highly effective despite partial saturation. Simulations identified Synthetic Control Methods (SCM) and its variant, count Synthetic Control Method (cSCM), as superior in precision, with the smallest percentage errors in efficacy estimation. These methods also demonstrated robustness in placebo tests. CONCLUSIONS: Wolbachia interventions exhibit consistent protective effects against dengue. SCM and cSCM provided the most precise and robust estimates of IEs, validated across simulated and real-world settings.


Assuntos
Aedes , Dengue , Wolbachia , Wolbachia/fisiologia , Dengue/prevenção & controle , Dengue/epidemiologia , Animais , Aedes/microbiologia , Aedes/virologia , Humanos , Brasil/epidemiologia , Singapura/epidemiologia , Malásia/epidemiologia , Incidência , Controle de Mosquitos/métodos , Mosquitos Vetores/microbiologia , Simbiose , Controle Biológico de Vetores/métodos , Controle Biológico de Vetores/estatística & dados numéricos
4.
Cereb Cortex ; 33(7): 3401-3420, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35849820

RESUMO

Sensory neurons parse millisecond-variant sound streams like birdsong and speech with exquisite precision. The auditory pallial cortex of vocal learners like humans and songbirds contains an unconventional neuromodulatory system: neuronal expression of the estrogen synthesis enzyme aromatase. Local forebrain neuroestrogens fluctuate when songbirds hear a song, and subsequently modulate bursting, gain, and temporal coding properties of auditory neurons. However, the way neuroestrogens shape intrinsic and synaptic properties of sensory neurons remains unknown. Here, using a combination of whole-cell patch clamp electrophysiology and calcium imaging, we investigate estrogenic neuromodulation of auditory neurons in a region resembling mammalian auditory association cortex. We found that estradiol rapidly enhances the temporal precision of neuronal firing via a membrane-bound G-protein coupled receptor and that estradiol rapidly suppresses inhibitory synaptic currents while sparing excitation. Notably, the rapid suppression of intrinsic excitability by estradiol was predicted by membrane input resistance and was observed in both males and females. These findings were corroborated by analysis of in vivo electrophysiology recordings, in which local estrogen synthesis blockade caused acute disruption of the temporal correlation of song-evoked firing patterns. Therefore, on a modulatory timescale, neuroestrogens alter intrinsic cellular properties and inhibitory neurotransmitter release to regulate the temporal precision of higher-order sensory neurons.


Assuntos
Córtex Auditivo , Tentilhões , Humanos , Masculino , Animais , Feminino , Estrogênios/farmacologia , Tentilhões/metabolismo , Vocalização Animal/fisiologia , Estradiol , Córtex Auditivo/fisiologia , Neurônios/fisiologia , Mamíferos/metabolismo
5.
J Am Chem Soc ; 145(19): 10576-10583, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37130260

RESUMO

Li and Na metals with high energy density are promising in application in rechargeable batteries but suffer from degradation in the ambient atmosphere. The phenomenon that in terms of kinetics, Li is stable but Na is unstable in dry air has not been fully understood. Here, we use in situ environmental transmission electron microscopy combined with theoretical simulations and reveal that the different stabilities in dry air for Li and Na are reflected by the formation of compact Li2O layers on Li metal, while porous and rough Na2O/Na2O2 layers on Na metal are a consequence of the different thermodynamic and kinetics in O2. It is shown that a preformed carbonate layer can change the kinetics of Na toward an anticorrosive behavior. Our study provides a deeper understanding of the often-overlooked chemical reactions with environmental gases and enhances the electrochemical performance of Li and Na by controlling interfacial stability.

6.
Neurobiol Dis ; 183: 106176, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37263384

RESUMO

Aminoglycoside antibiotics (AGAs) are widely used in life-threatening infections, but they accumulate in cochlear hair cells (HCs) and result in hearing loss. Increases in adenosine triphosphate (ATP) concentrations and P2X7 receptor expression were observed after neomycin treatment. Here, we demonstrated that P2X7 receptor, which is a non-selective cation channel that is activated by high ATP concentrations, may participate in the process through which AGAs enter hair cells. Using transgenic knockout mice, we found that P2X7 receptor deficiency protects HCs against neomycin-induced injury in vitro and in vivo. Subsequently, we used fluorescent gentamicin-Fluor 594 to study the uptake of AGAs and found fluorescence labeling in wild-type mice but not in P2rx7-/- mice in vitro. In addition, knocking-out P2rx7 did not significantly alter the HC count and auditory signal transduction, but it did inhibit mitochondria-dependent oxidative stress and apoptosis in the cochlea after neomycin exposure. We thus conclude that the P2X7 receptor may be linked to the entry of AGAs into HCs and is likely to be a therapeutic target for auditory HC protection.


Assuntos
Aminoglicosídeos , Ototoxicidade , Animais , Camundongos , Aminoglicosídeos/toxicidade , Aminoglicosídeos/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Ototoxicidade/metabolismo , Antibacterianos/toxicidade , Neomicina/toxicidade , Neomicina/metabolismo , Células Ciliadas Auditivas/metabolismo , Cóclea , Trifosfato de Adenosina/metabolismo
7.
Small ; 19(29): e2301824, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37183295

RESUMO

Despite the unprecedented progress in lead-based perovskite solar cells (PSCs), the toxicity and leakage of lead from degraded PSCs triggered by deep-level defects and poor crystallization quality increase environmental risk and become a critical challenge for eco-friendly PSCs. Here, a novel 2D polyoxometalate (POM)-based metal-organic framework (MOF) (C5 NH5 )4 (C3 N2 H5 )2 Zn3 (H8 P4 Mo6 O31 )2 ·2H2 O (POMOF) is ingeniously devised to address these issues. Note that the integration of POM endows POMOF with great advantages of electrical conductivity and charge mobility. Ordered POMOF induces the crystallization of high-quality perovskite film and eliminates lead-based defects to improve internal stability. The resultant PSCs achieve a superior power conversion efficiency (23.3%) accompanied by improved stability that maintains ≈90% of its original efficiency after 1600 h. Meanwhile, POMOF with phosphate groups effectively prevents lead leakage through in situ chemical anchoring and adsorption methods to reduce environmental risk. This work provides an effective strategy to minimize lead-based defects and leakage in sustainable PSCs through multi-functional POM-based MOF material.

8.
Mol Ther ; 30(1): 105-118, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34174443

RESUMO

Myosin VI(MYO6) is an unconventional myosin that is vital for auditory and vestibular function. Pathogenic variants in the human MYO6 gene cause autosomal-dominant or -recessive forms of hearing loss. Effective treatments for Myo6 mutation causing hearing loss are limited. We studied whether adeno-associated virus (AAV)-PHP.eB vector-mediated in vivo delivery of Staphylococcus aureus Cas9 (SaCas9-KKH)-single-guide RNA (sgRNA) complexes could ameliorate hearing loss in a Myo6WT/C442Y mouse model that recapitulated the phenotypes of human patients. The in vivo editing efficiency of the AAV-SaCas9-KKH-Myo6-g2 system on Myo6C442Y is 4.05% on average in Myo6WT/C442Y mice, which was ∼17-fold greater than editing efficiency of Myo6WT alleles. Rescue of auditory function was observed up to 5 months post AAV-SaCas9-KKH-Myo6-g2 injection in Myo6WT/C442Y mice. Meanwhile, shorter latencies of auditory brainstem response (ABR) wave I, lower distortion product otoacoustic emission (DPOAE) thresholds, increased cell survival rates, more regular hair bundle morphology, and recovery of inward calcium levels were also observed in the AAV-SaCas9-KKH-Myo6-g2-treated ears compared to untreated ears. These findings provide further reference for in vivo genome editing as a therapeutic treatment for various semi-dominant forms of hearing loss and other semi-dominant diseases.


Assuntos
Edição de Genes , Perda Auditiva , Animais , Modelos Animais de Doenças , Potenciais Evocados Auditivos do Tronco Encefálico/genética , Audição , Perda Auditiva/genética , Perda Auditiva/terapia , Humanos , Camundongos , RNA Guia de Cinetoplastídeos
9.
Int J Mol Sci ; 24(6)2023 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-36982915

RESUMO

Resmetirom, a liver-directed, orally active agonist of THR-ß, could play a favorable role in treating NASH, but little is known about the underlying mechanism. A NASH cell model was established to test the preventive effect of resmetirom on this disease in vitro. RNA-seq was used for screening, and rescue experiments were performed to validate the target gene of the drug. A NASH mouse model was used to further elucidate the role and the underlying mechanism of resmetirom. Resmetirom effectively eliminated lipid accumulation and decreased triglyceride (TG) levels. In addition, repressed RGS5 in the NASH model could be recovered by resmetirom treatment. The silencing of RGS5 effectively impaired the role of resmetirom. In the NASH mouse model, obvious gray hepatization, liver fibrosis and inflammation, and increased macrophage infiltration were observed in liver tissues, while resmetirom almost returned them to normal conditions as observed in the control group. Pathological experimental data also confirmed that resmetirom has great potential in NASH treatment. Finally, RGS5 expression was suppressed in the NASH mouse model, but it was upregulated by resmetirom treatment, while the STAT3 and NF-κB signaling pathways were activated in NASH but inhibited by the agent. Resmetirom could improve NASH by recovering RGS5 expression and subsequently inactivating the STAT3 and NF-κB signaling pathways.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Proteínas RGS , Camundongos , Animais , NF-kappa B/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Transdução de Sinais , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Proteínas RGS/genética , Proteínas RGS/metabolismo
10.
Zhongguo Zhong Yao Za Zhi ; 48(10): 2646-2656, 2023 May.
Artigo em Zh | MEDLINE | ID: mdl-37282926

RESUMO

This study aimed to explore the effects and mechanisms of total flavones of Abelmoschus manihot(TFA), the extracts from traditional Chinese medicine indicated for kidney diseases, on insulin resistance(IR) and podocyte epithelial-mesenchymal transition(EMT) in diabetic kidney disease(DKD), and further to reveal the scientific connotation. Thirty-two rats were randomly divided into a normal group, a model group, a TFA group, and a rosiglitazone(ROS) group. The modified DKD model was induced in rats by methods including high-fat diet feeding, unilateral nephrectomy, and streptozotocin(STZ) intraperitoneal injection. After modeling, the rats in the four groups were given double-distilled water, TFA suspension, and ROS suspension correspondingly by gavage every day. At the end of the 8th week of drug administration, all rats were sacrificed, and the samples of urine, blood, and kidney tissues were collected. The parameters and indicators related to IR and podocyte EMT in the DKD model rats were examined and observed, including the general condition, body weight(BW) and kidney weight(KW), the biochemical parameters and IR indicators, the protein expression levels of the key signaling molecules and structural molecules of slit diaphragm in the renal insulin receptor substrate(IRS) 1/phosphatidylinositol 3-kinase(PI3K)/serine-threonine kinase(Akt) pathway, foot process form and glomerular basement membrane(GBM) thickness, the expression of the marked molecules and structural molecules of slit diaphragm in podocyte EMT, and glomerular histomorphological characteristics. The results showed that for the DKD model rats, both TFA and ROS could improve the general condition, some biochemical parameters, renal appearance, and KW. The ameliorative effects of TFA and ROS were equivalent on BW, urinary albumin(UAlb)/urinary creatinine(UCr), serum creatinine(Scr), triglyceride(TG), and KW. Secondly, they could both improve IR indicators, and ROS was superior to TFA in improving fast insulin(FIN) and homeostasis model assessment of insulin resistance(HOMA-IR). Thirdly, they could both improve the protein expression levels of the key signaling molecules in the IRS1/PI3K/Akt pathway and glomerulosclerosis in varying degrees, and their ameliorative effects were similar. Finally, both could improve podocyte injury and EMT, and TFA was superior to ROS. In conclusion, this study suggested that podocyte EMT and glomerulosclerosis could be induced by IR and the decreased activation of the IRS1/PI3K/Akt pathway in the kidney in DKD. Similar to ROS, the effects of TFA in inhibiting podocyte EMT in DKD were related to inducing the activation of the IRS1/PI3K/Akt pathway and improving IR, which could be one of the scientific connotations of TFA against DKD. This study provides preliminary pharmacological evidence for the development and application of TFA in the field of diabetic complications.


Assuntos
Abelmoschus , Diabetes Mellitus , Nefropatias Diabéticas , Flavonas , Resistência à Insulina , Podócitos , Ratos , Animais , Nefropatias Diabéticas/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Abelmoschus/química , Ratos Sprague-Dawley , Transição Epitelial-Mesenquimal , Flavonas/farmacologia , Espécies Reativas de Oxigênio
11.
J Neurosci ; 41(8): 1625-1635, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33446517

RESUMO

Proper perception of sounds in the environment requires auditory signals to be encoded with extraordinary temporal precision up to tens of microseconds, but how it originates from the hearing organs in the periphery is poorly understood. In particular, sound-evoked spikes in auditory afferent fibers in vivo are phase-locked to sound frequencies up to 5 kHz, but it is not clear how hair cells can handle intracellular Ca2+ changes with such high speed and efficiency. In this study, we combined patch-clamp recording and two-photon Ca2+ imaging to examine Ca2+ dynamics in hair cell ribbon synapses in the bullfrog amphibian papilla of both sexes. We found that Ca2+ clearance from single synaptic ribbons followed a double exponential function, and the weight of the fast component, but not the two time constants, was significantly reduced for prolonged stimulation, and during inhibition of the plasma membrane Ca2+ ATPase (PMCA), the mitochondrial Ca2+ uptake (MCU), or the sarcolemma/endoplasmic reticulum Ca2+ ATPase (SERCA), but not the Na+/Ca2+ exchanger (NCX). Furthermore, we found that both the basal Ca2+ level and the Ca2+ rise during sinusoidal stimulation were significantly increased by inhibition of PMCA, MCU, or SERCA. Consistently, phase-locking of synaptic vesicle releases from hair cells was also significantly reduced by blocking PMCA, MCU, or SERCA, but not NCX. We conclude that, in addition to fast diffusion mediated by mobile Ca2+ buffer, multiple Ca2+ extrusion pumps are required for phase-locking at the auditory hair cell ribbon synapse.SIGNIFICANCE STATEMENT Hair cell synapses can transmit sound-driven signals precisely in the kHz range. However, previous studies of Ca2+ handling in auditory hair cells have often been conducted in immature hair cells, with elevated extracellular Ca2+ concentration, or through steady-state stimulation that may not be physiologically relevant. Here we examine Ca2+ clearance from hair cell synaptic ribbons in a fully mature preparation at physiological concentration of external Ca2+ and at physiological temperature. By stimulating hair cells with sinusoidal voltage commands that mimic pure sound tones, we recapitulated the phase-locking of hair cell exocytosis with an in vitro approach. This allowed us to reveal the Ca2+ extrusion mechanisms that are required for phase-locking at auditory hair cell ribbon synapses.


Assuntos
Cálcio/metabolismo , Potenciais Pós-Sinápticos Excitadores/fisiologia , Células Ciliadas Auditivas Internas/fisiologia , Sinapses/fisiologia , Animais , Exocitose/fisiologia , Feminino , Masculino , Rana catesbeiana , Vesículas Sinápticas/metabolismo
12.
Anal Chem ; 94(40): 13810-13819, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36184789

RESUMO

Since the outbreak of coronavirus disease 2019 (COVID-19), the epidemic has been spreading around the world for more than 2 years. Rapid, safe, and on-site detection methods of COVID-19 are in urgent demand for the control of the epidemic. Here, we established an integrated system, which incorporates a machine-learning-based Fourier transform infrared spectroscopy technique for rapid COVID-19 screening and air-plasma-based disinfection modules to prevent potential secondary infections. A partial least-squares discrimination analysis and a convolutional neural network model were built using the collected infrared spectral dataset containing 857 training serum samples. Furthermore, the sensitivity, specificity, and prediction accuracy could all reach over 94% from the results of the field test regarding 968 blind testing samples. Additionally, the disinfection modules achieved an inactivation efficiency of 99.9% for surface and airborne tested bacteria. The proposed system is conducive and promising for point-of-care and on-site COVID-19 screening in the mass population.


Assuntos
COVID-19 , COVID-19/diagnóstico , Humanos , Análise dos Mínimos Quadrados , Redes Neurais de Computação , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
13.
Small ; 18(29): e2202069, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35739615

RESUMO

Replacing liquid electrolytes with solid polymer electrolytes (SPEs) is considered as a vital approach to developing sulfur (S)-based cathodes. However, the polysulfides shuttle and the growth of lithium (Li) dendrites are still the major challenges in polyethylene oxide (PEO)-based electrolyte. Here, an all-solid-state Li metal battery with flexible PEO-Li10 Si0.3 PS6.7 Cl1.8 (LSPSCl)-C-lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) composite cathode (FCC) and PEO-LSPSCl-LiTFSI composite electrolyte (S-CPE) is designed. The initial capacity of the Li|S-CPE|FCC battery is 414 mAh g-1 with 97.8% capacity retention after 100 cycles at 0.1 A g-1 . Moreover, the battery displays remarkable capacity retention of 80% after 500 cycles at 0.4 A g-1 . Cryo-transmission electron microscopy (Cryo-TEM) reveals rich large-sized Li2 CO3 particles at the Li/PEO interface blocking the Li+ transport, but the layer with rich Li2 O nanocrystals, amorphous LiF and Li2 S at the Li/S-CPE interface suppresses the growth of lithium dendrite and stabilizes the interface. In situ optical microscopy demonstrates that the excellent cyclic stability of FCC is ascribed to the reversible shuttle of P-S-P species, resulting from the movement of ether backbone in PEO. This study provides strategies to mitigate the polysulfide shuttle effect and Li dendrite formation in designing high energy density solid-state Li-S-based batteries.

14.
Clin Genet ; 102(2): 149-154, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35599357

RESUMO

The pathogenic variants in KCNQ4 cause DFNA2 nonsyndromic hearing loss. However, the understanding of genotype-phenotype correlations between KCNQ4 and hearing is limited. Here, we identified a novel KCNQ4 mutation p.G228D from a Chinese family, including heterozygotes characterized by high-frequency hearing loss that is progressive across all frequencies and homozygotes with more severe hearing loss. We constructed a novel murine model with humanized homologous Kcnq4 mutation. The heterozygotes had mid-frequency and high-frequency hearing loss at 4 weeks, and moved toward all frequencies hearing loss at 12 weeks, while the homozygotes had severe-to-profound hearing loss at 8 weeks. The degeneration of outer hair cells (OHCs) was observed from basal to apical turn of cochlea. The reduced K+ currents and depolarized resting potentials were revealed in OHCs. Remarkably, we observed the loss of inner hair cells (IHCs) in the region corresponding to the frequency above 32 kHz at 8-12 weeks. The results suggest the degeneration of OHCs and IHCs may contribute to high-frequency hearing loss in DFNA2 over time. Our findings broaden the variants of KCNQ4 and provide a novel mouse model of progressive hearing loss, which contributes to an understanding of pathogenic mechanism and eventually treatment of DFNA2 progressive hearing loss.


Assuntos
Perda Auditiva de Alta Frequência , Canais de Potássio KCNQ , Animais , China , Modelos Animais de Doenças , Perda Auditiva de Alta Frequência/genética , Humanos , Canais de Potássio KCNQ/genética , Camundongos , Mutação
15.
Inorg Chem ; 61(8): 3690-3696, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35175767

RESUMO

Many methods have been utilized to adjust the size of superatomic metal nanoclusters, while tuning the geometric conformations of specific nanoclusters is rare. Here, we demonstrate that conformation variation can be realized by slightly modifying the ligand under maintaining the nuclei number of metal atoms. A series of novel "double-chair" conformation Ln12 (Ln = Sm (1), Eu (2), Gd (3), Tb (4), and Dy (5)) clusters were generated by replacing 3-formylsalicylic acid with 2,3-dihydroxybenzoic acid in the Ln12 nanocluster. Intriguingly, Dy12 displays slow magnetic relaxation at low temperatures, while Gd12 shows a large magnetocaloric effect (MCE) of 35.63 J kg-1 K-1 at 2 K for ΔH = 7 T. Additionally, the introduction of numerous coordination water molecules in these clusters enables Dy12 and Gd12 with high proton conductivity, namely, 2.13 × 10-4 and 3.62 × 10-4 S cm-1 under 358 K and 95% RH humidity conditions.

16.
J Nanobiotechnology ; 20(1): 398, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36045382

RESUMO

BACKGROUND: The ideal neural interface or scaffold for stem cell therapy shall have good biocompatibility promoting survival, maturation and integration of neural stem cells (NSCs) in targeted brain regions. The unique electrical, hydrophilic and surface-modifiable properties of Ti3C2Tx MXene make it an attractive substrate, but little is known about how it interacts with NSCs during development and maturation. RESULTS: In this study, we cultured NSCs on Ti3C2Tx MXene and examined its effects on morphological and electrophysiological properties of NSC-derived neurons. With a combination of immunostaining and patch-clamp recording, we found that Ti3C2Tx MXene promotes NSCs differentiation and neurite growth, increases voltage-gated current of Ca2+ but not Na+ or K+ in matured neurons, boosts their spiking without changing their passive membrane properties, and enhances synaptic transmission between them. CONCLUSIONS: These results expand our understanding of interaction between Ti3C2Tx MXene and NSCs and provide a critical line of evidence for using Ti3C2Tx MXene in neural interface or scaffold in stem cell therapy.


Assuntos
Células-Tronco Neurais , Titânio , Diferenciação Celular , Neurônios , Titânio/metabolismo , Titânio/farmacologia
17.
Microsc Microanal ; : 1-14, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35575050

RESUMO

This paper exploited an alternative approach to prepare high-quality speckle patterns by uniformly dispersing nano-silica particles onto sample surfaces, helping digital image correlation (DIC) acquire the maximum spatial resolution of local strain up to 92 nm. A case study was carried out by combining this speckle pattern fabrication method with SEM-DIC and electron backscattering diffraction (EBSD). Thus, in situ mapping of local strain with ultra-high spatial resolution and microstructure in commercially pure titanium during plastic deformation could be achieved, which favored revealing the effect of slip transfer on shear strain near grain boundaries. Moreover, the slip systems could be easily identified via the combination of the SEM-DIC and EBSD techniques even though no obvious deformation trace was captured in secondary electron images. Additionally, the complex geometric compatibility factor $( {m}^{\prime}_c)$ relating to geometric compatibility factors (mʹ) and Schmid factors was proposed to predict the shear strain (εxy) at grain boundaries.

18.
Zhongguo Zhong Yao Za Zhi ; 47(15): 4119-4127, 2022 Aug.
Artigo em Zh | MEDLINE | ID: mdl-36046902

RESUMO

To explore the effect and mechanism of Dahuang Zhechong Pills(DHZCP), a classical prescription, in improving testicular aging(TA) in vivo, the authors randomly divided 24 male rats into four groups: the normal, model, DHZCP and vitamin E(VE) groups. The TA rat model was established by continuous gavage of D-galactose(D-gal). During the experiment, the rats in the DHZCP and VE groups were given DHZCP suspension and VE suspension, respectively by gavage, while those in the normal and model groups were gavaged saline separately every day. After the co-administration of D-gal and various drugs for 60 days, all rats were sacrificed, and their blood and testis were collected. Further, various indexes related to TA and necroptosis of testicular cells in the model rats were examined and investigated, which included the aging phenotype, total testicular weight, testicular index, histopathological features of testis, number of spermatogenic cells, sex hormone level, expression characteristics of reactive oxygen species(ROS) in testis, expression levels and characteristics of cyclins in testis, and protein expression levels of the key molecules in receptor-interacting serine/threonine-protein kinase 1(RIPK1)/receptor-interacting serine/threonine-protein kinase 3(RIPK3)/mixed lineage kinase domain like pseudokinase(MLKL) signaling pathway in each group. The results showed that, for the TA model rats, both DHZCP and VE improved their aging phenotype, total testicular weight, testicular index, pathological features of testis, number of spermatogenic cells, serum testosterone and follicle stimulating hormone levels, expression characteristics of ROS and protein expression levels and characteristics of P21 and P53 in testis. In addition, DHZCP and VE improved the protein expression levels of the key molecules in RIPK1/RIPK3/MLKL signaling pathway in testis of the model rats. Specifically, DHZCP was better than VE in the improvement of RIPK3. In conclusion, in this study, the authors found that DHZCP, similar to VE, ameliorated D-gal-induced TA in model rats in vivo, and its mechanism was related to reducing necroptosis of testicular cells by inhibiting the activation of RIPK1/RIPK3/MLKL signaling pathway. This study provided preliminary pharmacological evidence for the development and application of classical prescriptions in the field of men's health.


Assuntos
Necroptose , Testículo , Envelhecimento , Animais , Medicamentos de Ervas Chinesas , Masculino , Proteínas Quinases/genética , Ratos , Espécies Reativas de Oxigênio/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/farmacologia , Serina/farmacologia , Transdução de Sinais , Treonina/farmacologia
19.
Development ; 145(20)2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-30275281

RESUMO

In vivo genetic mutation has become a powerful tool for dissecting gene function; however, multi-gene interaction and the compensatory mechanisms involved can make findings from single mutations, at best difficult to interpret, and, at worst, misleading. Hence, it is necessary to establish an efficient way to disrupt multiple genes simultaneously. CRISPR/Cas9-mediated base editing disrupts gene function by converting a protein-coding sequence into a stop codon; this is referred to as CRISPR-stop. Its application in generating zygotic mutations has not been well explored yet. Here, we first performed a proof-of-principle test by disrupting Atoh1, a gene crucial for auditory hair cell generation. Next, we individually mutated vGlut3 (Slc17a8), otoferlin (Otof) and prestin (Slc26a5), three genes needed for normal hearing function. Finally, we successfully disrupted vGlut3, Otof and prestin simultaneously. Our results show that CRISPR-stop can efficiently generate single or triple homozygous F0 mouse mutants, bypassing laborious mouse breeding. We believe that CRISPR-stop is a powerful method that will pave the way for high-throughput screening of mouse developmental and functional genes, matching the efficiency of methods available for model organisms such as Drosophila.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Zigoto/metabolismo , Sistemas de Transporte de Aminoácidos Acídicos/metabolismo , Animais , Sequência de Bases , Cóclea/metabolismo , Surdez/genética , Surdez/fisiopatologia , Modelos Animais de Doenças , Fenômenos Eletrofisiológicos , Proteínas de Membrana/metabolismo , Camundongos , Proteínas Motores Moleculares/metabolismo , Mutação/genética
20.
J Acoust Soc Am ; 149(1): 487, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33514169

RESUMO

This paper proposes a sound field separation technique based on the time-domain equivalent source method with single layer pressure-velocity measurements to extract the nonstationary sound field radiated by the target source in a reverberant environment. This technique constructs a formulation that relates the pressures and particle velocities on a measurement surface to the strengths of time-domain equivalent sources arranged for modelling the outgoing and incoming waves. By solving the strengths of time-domain equivalent sources, the sounds coming from different sides of the measurement surface can be separated independently. In the proposed technique, the use of a time-domain equivalent source model allows the measurement surface to be arbitrarily shaped, thus providing the ability to analyze the arbitrarily shaped sources in a reverberant environment. Numerical simulations investigated the performance of the proposed technique when using different types of arrays, including planar, semi-cylindrical, and semi-spherical arrays, and an experiment with three loudspeakers located at two sides of the measurement surface was carried out to test the validity of the proposed technique. Both numerical and experimental results demonstrate that the proposed technique can remove the influence of disturbing sources in both time and space domains and separate out the target sound fields effectively.

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