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1.
Nat Methods ; 20(10): 1563-1572, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37723244

RESUMO

Fluorescent RNAs, aptamers that bind and activate small fluorogenic dyes, have provided a particularly attractive approach to visualizing RNAs in live cells. However, the simultaneous imaging of multiple RNAs remains challenging due to a lack of bright and stable fluorescent RNAs with bio-orthogonality and suitable spectral properties. Here, we develop the Clivias, a series of small, monomeric and stable orange-to-red fluorescent RNAs with large Stokes shifts of up to 108 nm, enabling the simple and robust imaging of RNA with minimal perturbation of the target RNA's localization and functionality. In combination with Pepper fluorescent RNAs, the Clivias enable the single-excitation two-emission dual-color imaging of cellular RNAs and genomic loci. Clivias can also be used to detect RNA-protein interactions by bioluminescent imaging both in live cells and in vivo. We believe that these large Stokes shift fluorescent RNAs will be useful tools for the tracking and quantification of multiple RNAs in diverse biological processes.


Assuntos
Aptâmeros de Nucleotídeos , Corantes Fluorescentes , RNA , Microscopia de Fluorescência , Aptâmeros de Nucleotídeos/genética
2.
Phys Chem Chem Phys ; 25(16): 11176-11184, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37039244

RESUMO

Photoactivated fluorophores (PAFs) are powerful imaging tools for observing subcellular structures and tracking dynamic biological processes. However, photoremovable protecting groups (PPGs) widely used to construct PAFs suffer from the drawbacks of short-wavelength excitation and/or low photolysis efficiency. Herein, a class of coumarin-based PPGs with electron-rich thiophene derived substitutions at the C3-position of a coumarin scaffold were prepared. The modification not only leads to the redshift of the absorption band to the blue light region (400-500 nm), but also the increases of uncaging quantum yield (Φu) as well as molar extinction coefficient (εmax), thus enhancing the photolysis efficiency (Φu × Îµmax) up to 34.2 × 103 M-1 cm-1. The exceptionally high photolysis efficiency enables efficient photolysis in blue light as weak as 2 mW cm-2 or in blue light from a Luminol chemiluminescence system. Based on the excellent photolysis properties, the PAF constructed by the new PPG exhibits fast photoactivation and a low background signal, and the resulting fluorescence images display a signal-to-noise ratio greater than 780. It is anticipated that the superior photolysis performance makes the PPGs a novel platform for the construction of photo responsive systems in a variety of applications.

3.
Small ; 18(33): e2202139, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35871546

RESUMO

SiOx suspension is regarded as an attractive anolyte for high-energy-density Li-ion slurry flow batteries. However, the poor electronic conductivity and non-negligible volume variation of SiOx greatly hinder its practical applications. Herein, these issues are successfully addressed by rationally designing a trifunctional interface with mixed electron/ion and hard/soft modulated properties on SiOx surface via H-bonding interactions. The interface comprises a lithiated polymer layer (LiPN) interfused with functionalized single-walled carbon nanotubes. Carbon nanotubes work as electrical tentacles to enhance the multiscale electron conduction. The LiPN layer with transferable Li-ions facilitates ion transport. In addition, the LiPN layer employs lithiated rigid polyacrylic acid as a framework to provide mechanical support and soft nafion as a buffer to accommodate volume change, which maintains the structural integrity of SiOx . Hence, SiOx @LiPN/S anolytes exhibit significantly improved rate and cycle performances. Specially, the interface enables the anolytes to load more active particles (30 wt%) or less conductive additives (0.4 wt%). The semi-solid pouch cells based on high-active-content anolytes with stable cyclability are first demonstrated and the flow cell using low-conductive-content anolytes displays a high volumetric capacity of 207 Ah L-1 . This strategy paves a novel approach for optimizing semi-solid electrodes for high-performance Li-ion slurry flow batteries.

4.
Bioconjug Chem ; 30(1): 184-191, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30566325

RESUMO

Protein covalent labeling is dramatically useful for studying protein function in living cells and organisms. In this field, the chemical tag technique combined with fluorogenic probes has emerged as a powerful tool. Herein, a series of TMP tag fluorogenic probes have been developed to span the green to full blue spectral range. These probes feature an acrylamide unit that acts as a linker group to conjugate the fluorophore and the ligand as well as a quencher and a covalent reaction group. After the probes bind to eDHFR:L28C, the acrylamide unit specifically reacts with the thiol group of the L28C residue beside the ligand binding pocket, achieving protein-specific labeling without any liberation of leaving groups. With these probes, multicolor and specific protein labeling with a fast reaction rate ( t1/2 = 33 s) and dramatic fluorescence enhancement (4000-fold) were obtained. Furthermore, no-wash protein labeling in both living cells and zebrafish was successfully achieved. We expect it may provide a general and highly effective chemical tool for the study of protein function in living cells and organisms.


Assuntos
Acrilamida/química , Corantes Fluorescentes/química , Imagem Molecular/métodos , Razão Sinal-Ruído , Acrilamida/metabolismo , Animais , Núcleo Celular/metabolismo , Corantes Fluorescentes/metabolismo , Células HEK293 , Células HeLa , Humanos , Ligantes , Tetra-Hidrofolato Desidrogenase/genética , Peixe-Zebra
5.
Angew Chem Int Ed Engl ; 57(14): 3722-3726, 2018 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-29446517

RESUMO

A new class of coumarin photocaging groups modified with an electron-rich styryl moiety at the 3-position was constructed. The large π-conjugated structure and stabilization of the carbocation intermediates by electron donors endowed the new photocaging groups with excellent long-wavelength absorption, large two-photon absorption cross-sections, and high uncaging quantum yields. Moreover, the new photocaging groups displayed unique photobleaching properties after photocleavage as a result of the intramolecular cyclization rearrangement of a carbocation intermediate to form five-membered ring byproducts and block the styryl conjugation at the 3-position. These superior properties of the new photocaging groups are extremely beneficial for high-concentration samples and thick specimens, thus extending the application of photocaging groups in many fields.

6.
Angew Chem Int Ed Engl ; 56(41): 12599-12602, 2017 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-28763146

RESUMO

Solid-state plasticity by dynamic covalent bond exchange in a shape-memory polymer network bestows a permanent shape reconfiguration ability. Spatio-selective control of thermally induced plasticity may further extend the capabilities of materials into unexplored domains. However, this is difficult to achieve because of the lack of spatio-control in typical polymer network synthesis. Metal-ligand interactions possess the high strength of covalent bonds while maintaining the dynamic reversibility of supramolecular bonds. Metallosupramolecular shape-memory polymer networks were designed and prepared, which demonstrated solid-state plasticity. The metallo-coordination bonds within these networks permit facile tuning of the plasticity behavior across a wide temperature range, simply by changing the metal ion. By controlling the diffusion of two different metal ions during preparation of a polymer film, a plasticity behavior with a spatial gradient was achieved, providing a unique shape-morphing versatility with potential in shape-memory devices.

7.
Planta Med ; 80(12): 974-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25098932

RESUMO

The purpose of this study was to evaluate the effects of quercetin-3-O-sambubioside on the neural system. Quercetin-3-O-sambubioside is a monomeric compound found in Eucommia ulmoides male flowers from which it was extracted using a system solvent method. In the experiments, spontaneous activity and convulsion rate in mice were recorded, and quercetin-3-O-sambubioside shows eminent effects similar to nikethamide on increasing spontaneous activity and stimulating the nerve center to enhance excitement. These findings are indicative of the powerful ability of quercetin-3-O-sambubioside to promote the stimulation of the nerve center.


Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Eucommiaceae/química , Glicosídeos/farmacologia , Extratos Vegetais/farmacologia , Quercetina/análogos & derivados , Convulsões/induzido quimicamente , Animais , Flores/química , Glicosídeos/isolamento & purificação , Masculino , Camundongos Endogâmicos , Quercetina/isolamento & purificação , Quercetina/farmacologia
8.
Plants (Basel) ; 13(17)2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39274016

RESUMO

Microtubules undergo dynamic remodeling in response to diverse abiotic stress in plants. The plant-specific IQ67 DOMAIN (IQD) family proteins serve as microtubule-associated proteins, playing multifaceted roles in plant development and response to abiotic stress. However, the biological function of IQD genes in apple remains unclear. In this study, we conducted a comprehensive analysis of the Malus domestica genome, identifying 42 IQD genes distributed across 17 chromosomes and categorized them into four subgroups. Promoter analysis revealed the presence of stress-responsive elements. Subsequent expression analysis highlighted the significant upregulation of MdIQD17 and MdIQD28 in response to cold treatments, prompting their selection for further functional investigation. Subcellular localization studies confirmed the association of MdIQD17 and MdIQD28 with microtubules. Crucially, confocal microscopy and quantification revealed diminished microtubule depolymerization in cells transiently overexpressing MdIQD17 and MdIQD28 compared to wild-type cells during cold conditions. In conclusion, this study provides a comprehensive analysis of IQD genes in apple, elucidating their molecular mechanism in response to cold stress.

9.
Chem Commun (Camb) ; 59(14): 1963-1966, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36722975

RESUMO

A facile hydrogel fabrication strategy based on a simultaneous dual-photo-coupling reaction (i.e., photoinduced S-nitrosylation and Schiff base reaction) was reported. This strategy allowed a strengthened three-arm crosslinking network to form in one step and the hydrogels obtained displayed rapid gelation, excellent mechanical strength and biocompatibility for cell encapsulated-3D printing in real time. Our hydrogel fabrication strategy will likely foster advances in biomaterials and the extreme speed and reinforced mechanical strength should significantly benefit 3D printing and related applications.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Impressão Tridimensional , Engenharia Tecidual
10.
Chem Commun (Camb) ; 59(47): 7287, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37249565

RESUMO

Correction for 'Reinforced hydrogel network building by a rapid dual-photo-coupling reaction for 3D printing' by Renjie Zhou et al., Chem. Commun., 2023, 59, 1963-1966, https://doi.org/10.1039/D2CC05677A.

11.
Cell Discov ; 9(1): 56, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37311750

RESUMO

Naturally occurring fluorescent proteins (FPs) are the most widely used tools for tracking cellular proteins and sensing cellular events. Here, we chemically evolved the self-labeling SNAP-tag into a palette of SNAP-tag mimics of fluorescent proteins (SmFPs) that possess bright, rapidly inducible fluorescence ranging from cyan to infrared. SmFPs are integral chemical-genetic entities based on the same fluorogenic principle as FPs, i.e., induction of fluorescence of non-emitting molecular rotors by conformational locking. We demonstrate the usefulness of these SmFPs in real-time tracking of protein expression, degradation, binding interactions, trafficking, and assembly, and show that these optimally designed SmFPs outperform FPs like GFP in many important ways. We further show that the fluorescence of circularly permuted SmFPs is sensitive to the conformational changes of their fusion partners, and that these fusion partners can be used for the development of single SmFP-based genetically encoded calcium sensors for live cell imaging.

12.
Dis Markers ; 2022: 6853939, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35096206

RESUMO

OBJECTIVE: To elucidate the correlation between expression levels of long noncoding RNA (lncRNA) ROR and microRNA-125b (miR-125b) with the prognosis in heart failure (HF) patients combined acute renal failure (ARF). METHODS: HF patients combined ARF (n = 90) and healthy controls (n = 90) in the same period were included in our hospital from April 2016 to December 2018. Every subject was followed up for 24 months. Serum levels of lncRNA ROR and miR-125b were detected, and their expression correlation was analyzed by Pearson correlation test. Receiver operating characteristic (ROC) curves were depicted for assessing the sensitivity and specificity of lncRNA ROR and miR-125b in diagnosing HF combined ARF. RESULTS: lncRNA ROR was upregulated in serum of HF patients combined ARF, and its level was positively correlated to NYHA classification. miR-125b displayed an opposite trend. In serum samples of HF combined ARF, expression level of lncRNA ROR was negatively related to that of miR-125b. Diagnostic potentials of lncRNA ROR and miR-125b in HF combined ARF were confirmed by ROC curve analyses (lncRNA ROR: AUC = 0.9199, cutoff value = 5.595, sensitivity = 92.22%, and specificity = 73.33%; miR-125b: AUC = 0.8509, cutoff value = 2.290, sensitivity = 81.11%, and specificity = 74.44%). After 2-year follow-up, 16 cases were dead. Higher incidences of death and rehospitalization were observed in HF combined ARF cases expressing higher serum level of lncRNA ROR or lower level of miR-125b. CONCLUSIONS: Serum level of lncRNA ROR is upregulated, and miR-125b is downregulated in HF patients combined ARF. Their levels are linked to NYHA classification, which can be utilized as prognostic biomarkers in HF combined ARF.


Assuntos
Injúria Renal Aguda , Insuficiência Cardíaca , MicroRNAs , RNA Longo não Codificante , Injúria Renal Aguda/genética , Insuficiência Cardíaca/genética , Humanos , Prognóstico , RNA Longo não Codificante/genética
13.
Neuropsychiatr Dis Treat ; 18: 1653-1664, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35968511

RESUMO

Purpose: To determine the relative safety and efficacy of different doses of tandospirone in treating generalized anxiety disorder (GAD). Patients and Methods: This parallel randomized controlled trial enrolled patients with GAD from eight centers in China. The patients were randomly assigned to 60 mg/day or 30 mg/day tandospirone groups. The primary endpoint was the overall response rate after receiving 6-week treatment. The secondary endpoints included significant response rate, clinical recovery rate, change in the Hamilton Anxiety Scale (HAMA) total score, HAMA subscale score, Hamilton Depression Scale-17 (HAMD-17), Clinical Global Impression-Severity Scale (CGI-S) score, and Impression-Improvement scale (CGI-I) score. Results: No significant difference was found in the overall response rate between the two groups (65.7% vs 58.4%, p = 0.213). A higher significant response rate and change in the HAMA total score were found in the 60 mg/day group. The reduction in the CGI-S score and percentage of patients with a CGI-I score of ≤2 were higher in 60 mg/day group. The reduction in HAMA somatic anxiety factor, cardiovascular symptom factor, gastrointestinal symptom factor, and HAMD-17 score were more significant in the 60 mg/day group. The incidence of total adverse events was higher in the 60 mg/day group than in the 30 mg/day group. No significant difference was found in the proportion of withdrawal due to adverse events. Conclusion: Both 60 mg/day and 30 mg/day tandospirone show good efficacy in treating patients with GAD. High doses of tandospirone may have advantages in relieving the somatic symptoms but also present disadvantages due to their high level. Trial Registration: The trial registration no. was NCT01614041.

14.
Biomed Res Int ; 2021: 8884438, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33490282

RESUMO

PURPOSE: Ample evidence has proved that lncRNAs are pivotal regulators in acute kidney injury (AKI). Here, we focus on the role and mechanism of lncRNA SNHG14 in ischemia/reperfusion- (I/R-) caused AKI. METHODS: I/R and hypoxia/reoxygenation (H/R) were applied to induce rats and HK-2 cells to establish AKI models in vivo and in vitro. Relative expression of SNHG14, miR-124-3p, and MMP2 was determined by qRT-PCR. HE staining was used to evaluate pathological changes in renal tissues, and acute tubular necrosis (ATN) score was calculated. Renal function was evaluated by measuring serum creatinine content and blood urea nitrogen content. Levels of IL-1ß, IL-6, and TNF-α were measured by ELISA. Cell viability was examined by MTT assay. Oxidative stress was assessed by measuring SOD, MDA, and ROS levels. The target of SNHG14 or miR-124-3p was verified by DLR assay. Protein expression of MMP2 was examined by western blot. RESULTS: SNHG14 was boosted in renal tissues of I/R-stimulated rats and H/R-induced HK-2 cells, while miR-124-3p was diminished in H/R-stimulated HK-2 cells. Si-SNHG14 or miR-124-3p mimics repressed inflammation and oxidative stress and enhanced cell viability in H/R-stimulated HK-2 cells. Sh-SNHG14 mitigated I/R-induced AKI in rats. MiR-124-3p was targeted by SNHG14, and MMP2 was targeted by miR-124-3p. Inhibition of miR-124-3p or upregulation of MMP2 reversed inhibitory effects of SNHG14 silence on inflammation and oxidative stress as well as the promoting effect of SNHG14 silence on cell viability in H/R-induced HK-2 cells. CONCLUSION: Knockdown of SNHG14 alleviated I/R-induced AKI by miR-124-3p-mediated downregulation of MMP2.


Assuntos
Injúria Renal Aguda/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante , Traumatismo por Reperfusão/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular , Citocinas/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Rim/metabolismo , Masculino , Estresse Oxidativo/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ratos , Ratos Sprague-Dawley
15.
World J Clin Cases ; 9(24): 7231-7236, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34540983

RESUMO

BACKGROUND: Splenic hamartoma (SH) is a rare, benign vascular proliferation that is often found incidentally. It may be misdiagnosed as a splenic aneurysm or splenic malignancy. CASE SUMMARY: A 21-year-old male patient was admitted to our hospital with a complaint of an incidentally discovered asymptomatic splenic space-occupying lesion for 2 wk. Abdominal computed tomography (CT) scan showed a circular low-density shadow in the hilum of the spleen. Contrast-enhanced CT revealed an aneurysm located in the hilum of the spleen before operation. Laparoscopic splenectomy was performed and postoperative pathology revealed the presence of SH. CONCLUSION: Imaging studies are insufficient for the differential diagnosis of SH from other diseases, and laparoscopic splenectomy is a less invasive procedure and useful for the diagnostic purpose as well.

16.
Front Neurol ; 11: 70, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117029

RESUMO

Cerebral cavernous malformations (CCMs) are the second most prevalent type of vascular malformation within the central nervous system. CCMs occur in two forms-sporadic and familial-the latter of which has an autosomal dominant mode of inheritance with incomplete penetrance and variable clinical expressivity. There are three genes considered to be associated with CCMs,-CCM1, which codes for KRIT1 protein; CCM2, which codes for MGC4607 protein; and CCM3, which codes for PDCD10 protein. To date, more than 74 gene mutations of CCM2 have been reported, and ~45% are deletion mutations. In this article, we disclose a novel CCM2 genetic variant (c.755delC, p.S252fs*40X) identified in a Chinese family to enrich the database of CCM2 genotypes.

17.
J Int Med Res ; 48(2): 300060519879006, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31601137

RESUMO

OBJECTIVE: We evaluated the diagnostic accuracy of computed tomography (CT)-guided transthoracic core needle biopsy (TCNB) for small (≤20-mm) lung nodules and identified predictive factors for true negatives among benign biopsy results. METHODS: From March 2010 to June 2015, 222 patients with small lung nodules underwent CT-guided TCNB. We retrospectively analysed data regarding technical success, diagnostic accuracy, and predictors of true negatives. RESULTS: The technical success rate was 100%. The TCNB results of the 222 lung nodules included malignancy (n = 136), suspected malignancy (n = 8), specific benign lesion (n = 17), and nonspecific benign lesion (n = 61). The final diagnosis of 222 lung nodules included malignant (n = 160), benign (n = 60), and nondiagnostic lesions (n = 2). The sensitivity, specificity, and overall diagnostic accuracy of CT-guided TCNB for small lung nodules were 90.0%, 100%, and 92.7%, respectively. Pneumothorax and haemoptysis occurred in 23 and 41 patients, respectively. Based on the Cox regression analysis, the significant independent predictive factor for true negatives was a biopsy result of chronic inflammation with fibroplasia. CONCLUSIONS: CT-guided TCNB offers high diagnostic accuracy for small lung nodules, and a biopsy result of chronic inflammation with fibroplasia can predict a true-negative result.


Assuntos
Neoplasias Pulmonares , Nódulo Pulmonar Solitário , Tomografia Computadorizada por Raios X , Idoso , Antígenos de Neoplasias , Feminino , Humanos , Biópsia Guiada por Imagem , Queratina-19 , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Nódulo Pulmonar Solitário/diagnóstico por imagem
18.
Nat Biotechnol ; 37(11): 1287-1293, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31548726

RESUMO

Fluorescent RNAs (FRs), aptamers that bind and activate fluorescent dyes, have been used to image abundant cellular RNA species. However, limitations such as low brightness and limited availability of dye/aptamer combinations with different spectral characteristics have limited use of these tools in live mammalian cells and in vivo. Here, we develop Peppers, a series of monomeric, bright and stable FRs with a broad range of emission maxima spanning from cyan to red. Peppers allow simple and robust imaging of diverse RNA species in live cells with minimal perturbation of the target RNA's transcription, localization and translation. Quantification of the levels of proteins and their messenger RNAs in single cells suggests that translation is governed by normal enzyme kinetics but with marked heterogeneity. We further show that Peppers can be used for imaging genomic loci with CRISPR display, for real-time tracking of protein-RNA tethering, and for super-resolution imaging. We believe these FRs will be useful tools for live imaging of cellular RNAs.


Assuntos
Aptâmeros de Nucleotídeos/genética , RNA/genética , RNA/metabolismo , Animais , Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes/química , Proteínas de Fluorescência Verde/química , Humanos , Mamíferos , Microscopia de Fluorescência , Biossíntese de Proteínas , RNA/química , Transcrição Gênica
20.
Rev. psicol. deport ; 32(1): 59-67, Abr 11, 2023. ilus, tab
Artigo em Inglês | IBECS (Espanha) | ID: ibc-218888

RESUMO

Ideological and political education (IPE) contributes to the efficacy of mental health education (MHE) for Chinese college students. This study aims to examine the function of cultural identity in the association between physical exercise (PE) and psychological abnormality among college students from the standpoint of IPE and PE. This study utilized a practical sampling strategy. The distribution of 1200 questionnaires to college students resulted in the recovery of 982 genuine surveys. Physical education and mental toughness are demonstrated to influence academic stress negatively. The cultivation period of the direct effect of physical education on higher education was not zero, indicating that the cultivation period was substantial. The psychological development period was not 0%, showing that emotional state had a major impact on physical education and educational stress and had a moderate influence. This study concluded that PE could promote and improve college students' mental health (MH). In addition, increasing national cultural identification can reduce the incidence of psychological disorders.(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Estudantes , Etnicidade , Exercício Físico , Esportes , Saúde Mental , Estresse Psicológico , Psicologia do Esporte , China , Inquéritos e Questionários
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