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1.
Otol Neurotol ; 44(2): e81-e87, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36624594

RESUMO

OBJECTIVE: The use of computer-based auditory training (CBAT) after cochlear implantation is associated with improved speech recognition and real-world functional abilities. However, patient-related factors associated with CBAT use remain unknown. This study seeks to identify such factors and recognize those at risk for not implementing CBAT. STUDY DESIGN: Prospective natural experiment. SETTING: Tertiary academic center. PATIENTS: A total of 117 new adult cochlear implant (CI) recipients with bilateral moderate-to-profound hearing loss. INTERVENTIONS/MAIN OUTCOME MEASURES: Patient demographic and lifestyle information, preimplantation aided speech recognition scores, Cochlear Implant Quality of Life (CIQOL) domain and global scores, CIQOL-Expectations scores, and CBAT use in the first 3 months after activation. Patient-related variables included age, sex, race, duration of hearing loss before implantation, hours of CI use per day, hearing-aid use before implantation, living arrangements/marital status, annual household income, employment, technology use, and education. RESULTS: Overall, 33 new CI users (28.2%) used CBAT in the first 3 months after activation. On bivariate analysis of the pre-CI CIQOL scores, CIQOL-Expectations score, aided speech recognition scores, and demographic/lifestyle factors examined, regular use of smartphone, tablet, or computer technology was significantly associated with an increased likelihood of CBAT use (odds ratio, 9.354 [1.198-73.020]), whereas higher CIQOL-Expectations emotional domain scores were associated with a lower likelihood of CBAT use (d = -0.69 [-1.34 to -0.05]). However, using multivariable analysis to control for potential confounding factors revealed no significant associations between CBAT use in the first 3 months after cochlear implantation and any examined factor. CONCLUSIONS: No associations between patient demographic, lifestyle, or pre-CI speech recognition and patient-reported outcome measures and CBAT use were identified. Therefore, discussions with all patients after implantation on the availability of CBAT and its potential benefits are warranted. In addition, given the limited overall use of CBAT and its association with improved CI outcomes, future studies are needed to investigate facilitators and barriers to CBAT use.


Assuntos
Implante Coclear , Implantes Cocleares , Auxiliares de Audição , Percepção da Fala , Humanos , Adulto , Qualidade de Vida , Estudos Prospectivos , Perda Auditiva Bilateral , Resultado do Tratamento
2.
Chem Commun (Camb) ; 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36661262

RESUMO

A novel probe was synthesized with a turn-on NIR fluorescent (NIRF)/photoacoustic (PA) response to NADPH, which was successfully applied in both monitoring intracellular NADPH and dual-modal imaging of tumor-bearing mice. It exhibits good potential in studying and understanding the tumor energy metabolism and treatment process related to NADPH.

3.
Biomed Pharmacother ; 159: 114264, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36652738

RESUMO

Liver fibrosis (LF) is an important stage in chronic liver disease development, characterized by hepatic stellate cell (HSC) activation and excessive extracellular matrix deposition. Phillygenin (PHI), an active component in the traditional Chinese medicine Forsythiae Fructus with a significant anti-inflammatory effect, has been proved to inhibit HSC activation. Macrophages can polarize to pro-inflammatory M1 phenotype and anti-inflammatory M2 phenotype, participating in LF development. Currently, Forsythiae Fructus and its many components have been proved to inhibit the inflammatory activation of macrophages. However, there is no direct evidence that PHI can regulate macrophage polarization, and the relationship between macrophage polarization and the anti-LF effect of PHI has not been studied. In this study, we found that PHI inhibited the co-expression of CD80 and CD86, and inhibited the mRNA expression and protein secretion of related inflammatory cytokines in RAW264.7 cells. For mechanism, PHI was found to inhibit the JAK1/JAK2-STAT1 and Notch1 signaling pathways. Subsequently, mHSCs were co-cultured with the conditioned media or exosomes from macrophages with different treatments. It was found that the conditioned media and exosomes from PHI-treated macrophages inhibited the expression of MMP2, TIMP1, TGF-ß, α-SMA, COL1 and NF-κB in mHSCs. Moreover, through bioinformatic analysis and cell transfection, we confirmed that PHI reduced HSC activation by inhibiting the overexpression of miR-125b-5p in M1 macrophage-derived exosomes and restoring Stard13 expression in mHSCs. On the whole, PHI could inhibit M1 macrophage polarization by suppressing the JAK1/JAK2-STAT1 and Notch1 signaling pathways, and reduce HSC activation by inhibiting macrophage exosomal miR-125b-5p targeting Stard13. DATA AVAILABILITY: The raw data supporting the conclusions of this study are available in the article/Supplementary figures, and can be obtained from the first or corresponding author.

4.
Adv Healthc Mater ; : e2202228, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36603210

RESUMO

Liver fibrosis is a progressive pathological process induced by various stimuli and may progress to liver cirrhosis and cancer. Forsythiaside A (FA) is an active ingredient extracted from traditional Chinese medicine Forsythiae Fructus and has prominent hepatoprotective activities. However, the unsatisfactory pharmacokinetic properties restrict its clinical application. In this study, the nanocarrier of CD44-specific ligand Hyaluronic acid (HA)-modified milk-derived exosomes (mExo) encapsulated with FA (HA-mExo-FA) is developed. As a result, HA modification could deliver drug-loaded exosomes to the target cells and form a specific ligand-receptor interaction with CD44, thus improving the anti-liver fibrosis effect of FA. In vitro findings indicate that HA-mExo-FA could inhibit TGF-ß1-induced LX2 cell proliferation, reduce α-SMA and collagen gene and protein levels, and promote the apoptosis of activated LX2 cells. In vivo results demonstrate that HA-mExo-FA could improve liver morphology and function changes in zebrafish larvae. The anti-liver fibrosis mechanism of HA-mExo-FA may be attributed to the inhibition of NLRP3-mediated pyroptosis. In addition, the effect of HA-mExo-FA on TAA-induced increase in NLRP3 production is attenuated by NLRP3 inhibitor MCC950. Collectively, this study demonstrates the promising application of HA-mExo-FA in drug delivery with high specificity and provides a powerful and novel delivery platform for liver fibrosis therapy.

5.
Cancer Invest ; : 1-10, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36715444

RESUMO

The association between DM and prostate cancer progression remains controversial. Previous studies mainly focused on early-stage prostate-cancer patients. We aimed to study the association between DM and prostate-cancer progression in locally-advanced prostate-cancer patients. 598 locally-advanced prostate-cancer patients in a top tertiary hospital in China between 2012-2021 were divided into three groups based on the postoperative-average HbA1c level. The follow-up time is 46.96 ± 27.07months. 348(58.2%) were normal-glucose, 175(29.3%) were moderate-glucose, and 75(12.5%) were high-glucose. Higher postoperative-average HbA1c was associated with poorer OS, PCSM and PSA-RFS (all p < 0.05). We concluded that poorly controlled DM was correlated with poorer OS, PCSM and PSA-RFS in locally-advanced prostate-cancer patients.

6.
Small ; : e2206982, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36703527

RESUMO

Intracerebral hemorrhage (ICH) remains a significant cause of morbidity and mortality around the world, and surgery is still the most direct and effective way to remove ICH. However, the potential risks brought by surgery, such as normal brain tissue damage, post-operative infection, and difficulty in removing deep hematoma, are still the main problems in the surgical treatment of ICH. Activation of the peroxisome proliferator-activated receptor gamma (PPARγ) is reported to show a good therapeutic effect in hematoma clearance. Herein, a magnetic targeting nanocarrier loaded with a PPARγ agonist (15d-PGJ2-MNPs) is synthesized, which could be magnetically targeted and enriched in the area of the hematoma after intravenous injection. Subsequent application of focusing ultrasound (FUS) could enhance drug diffusion, which activates the PPARγ receptors on macrophages around the hematoma for better hematoma clearance. The 15d-PGJ2-MNP treatment alleviates brain injury, accelerates hematoma clearance, attenuates neuroinflammation, reduces brain edema and significantly improves the deficits in sensory and motor function and spatial learning ability in the ICH mouse model. This work proposes an effective magnetic targeting plus FUS method to treat ICH, highlighting its great potential in the treatment of hemorrhagic stroke.

7.
Adv Healthc Mater ; : e2202814, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707970

RESUMO

Due to the safety issue and poor underwater adhesion of current commercially available bioadhesives, they are hard to apply to in vivo physiological environments and more diverse medical use conditions. In this study, a novel and facile bioadhesive for underwater medical applications was  designed based on the coacervation of electrostatic interactions and hydrophobic interactions, with the introduction of catechin (CC) as providers of catechol moieties for adhesion to surrounding tissues. The orange-colored bio-adhesive, named PcC, was  generated within seconds by mixing catechin-modified chondroitin sulfate (CSCC) and cholesterol chloroformate-modified polyethyleneimine (PEI-Chol) with agitation. In vitro mechanical measurements proved that this novel PcC bio-adhesive was  superior in underwater adhesion performance when applied to cartilage. Animal experiments in rat mastectomy model and rat cartilage graft implantation model have demonstrated its potential for diverse medical purposes, such as closing surgical incisions, reducing the formation of seroma, and tissue adhesive applied in orthopedic or cartilage surgery. This article is protected by copyright. All rights reserved.

8.
J Phys Chem Lett ; 14(3): 825-831, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36655858

RESUMO

Two-dimensional ferromagnetic Weyl half-metals that are robust against spin-orbital coupling were theoretically proposed recently, in which the nodal points and the nodal loops are protected by specific symmetries. As the symmetry of a ferromagnetic material is highly dependent on the magnetization orientation, here we predict a family of two-dimensional ferromagnetic Weyl half-metals, Mn2X3 (X = S, Se, Te) monolayers, to investigate the band topology under different magnetization orientations in the presence of spin-orbital coupling. The Curie temperatures (∼1000 K) were estimated to be much higher than room temperature due to the strong double exchange interaction and the suppression of spin fluctuation for the two-sublayer structure. Taking a Mn2Te3 monolayer as an example, we demonstrated the evolution of the nodal points and the nodal loops in the presence of spin-orbital coupling via manipulating magnetization orientation. Our work provides a family of high temperature two-dimensional ferromagnetic Weyl half-metals for investigating the nontrivial band topology.

9.
Neural Regen Res ; 18(5): 1107-1117, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36255000

RESUMO

Studies have found that the absence of glial cell line-derived neurotrophic factor may be the primary risk factor for Parkinson's disease. However, there have not been any studies conducted on the potential relationship between glial cell line-derived neurotrophic factor and cognitive performance in Parkinson's disease. We first performed a retrospective case-control study at the Affiliated Hospital of Xuzhou Medical University between September 2018 and January 2020 and found that a decreased serum level of glial cell line-derived neurotrophic factor was a risk factor for cognitive disorders in patients with Parkinson's disease. We then established a mouse model of Parkinson's disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and analyzed the potential relationships among glial cell line-derived neurotrophic factor in the prefrontal cortex, dopamine transmission, and cognitive function. Our results showed that decreased glial cell line-derived neurotrophic factor in the prefrontal cortex weakened dopamine release and transmission by upregulating the presynaptic membrane expression of the dopamine transporter, which led to the loss and primitivization of dendritic spines of pyramidal neurons and cognitive impairment. In addition, magnetic resonance imaging data showed that the long-term lack of glial cell line-derived neurotrophic factor reduced the connectivity between the prefrontal cortex and other brain regions, and exogenous glial cell line-derived neurotrophic factor significantly improved this connectivity. These findings suggested that decreased glial cell line-derived neurotrophic factor in the prefrontal cortex leads to neuroplastic degeneration at the level of synaptic connections and circuits, which results in cognitive impairment in patients with Parkinson's disease.

10.
Langmuir ; 39(1): 610-618, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36541927

RESUMO

Polymer-dispersed liquid crystals (PDLCs) are very attractive due to their electrically switchable properties. However, current PDLC films still have problems such as high driving voltages, low contrast ratio (CR), and poor bending resistance and spacing stability. To solve these problems, a PDLC film with a system of coexisting polymer spacer columns and polymer network was proposed. First, based on the adhesive systems of IBMA and UV6301, the effects of IBMA concentration and LC content on the morphology of the polymer network and the electro-optical properties of PDLC were investigated, respectively. Then, the effects of the process conditions of mask polymerization such as temperature, time, and UV light intensity on the morphology and electro-optical properties of the polymer spacer columns were systematically investigated. It was found that PDLC films with the coexistence system exhibit both excellent electro-optical properties and outstanding bending resistance and spacing stability. Thus, it provides new practical possibilities for the preparation of high-performance PDLC films used in flexible devices.

11.
Pharmacol Res ; 187: 106587, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36460279

RESUMO

Cucurbitacin B (CuB, C32H46O8), the most abundant and active member of cucurbitacins, which are highly oxidized tetracyclic triterpenoids. Cucurbitacins are widely distributed in a variety of plants and mainly isolated from plants in the Cucurbitaceae family. CuB is mostly obtained from the pedicel of Cucumis melo L. Modern pharmacological studies have confirmed that CuB has a broad range of pharmacological activities, with significant therapeutic effects on a variety of diseases including inflammatory diseases, neurodegenerative diseases, diabetes mellitus, and cancers. In this study the PubMed, Web of Science, Science Direct, and China National Knowledge Infrastructure (CNKI) databases were searched from 1986 to 2022. After inclusion and exclusion criteria were applied, 98 out of 2484 articles were selected for a systematic review to comprehensively summarize the pharmacological activity, toxicity, and pharmacokinetic properties of CuB. The results showed that CuB exhibits potent anti-inflammatory, antioxidant, antiviral, hypoglycemic, hepatoprotective, neuroprotective, and anti-cancer activities mainly via regulating various signaling pathways, such as the Janus kinase/signal transducer and activator of transcription-3 (JAK/STAT3), nuclear factor erythroid 2-related factor-2/antioxidant responsive element (Nrf2/ARE), nuclear factor (NF)-κB, AMP-activated protein kinase (AMPK), mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K)/Akt, cancerous inhibitor of protein phosphatase-2A/protein phosphatase-2A (CIP2A/PP2A), Wnt, focal adhesion kinase (FAK), Notch, and Hippo-Yes-associated protein (YAP) pathways. Studies of its toxicity and pharmacokinetic properties showed that CuB has non-specific toxicity and low bioavailability. In addition, derivatives and clinical applications of CuB are discussed in this paper.

12.
Exp Biol Med (Maywood) ; : 15353702221139209, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36533575

RESUMO

The aim of this study was to investigate the expression of serum homocysteine (HCY), procalcitonin (PCT), and C-reactive protein (CRP) in abdominal infectious disease and analyze their relationship with the degree of abdominal infection. We conducted a retrospective study involving 157 patients with abdominal infections at Xuzhou Central Hospital between January 2016 and October 2019. The patients were composed of intestinal obstruction (73 cases), appendicitis (45 cases), perforation of the digestive tract (25 cases), and cholecystitis (14 cases). The HCY, PCT, and CRP levels of patients with abdominal infections were detected using enzyme-linked immunosorbent assay (ELISA), and correlation analysis between the HCY, PCT, and CRP levels and abdominal infection was performed using Pearson's correlation analysis. Compared with before treatment, the HCY, PCT, and CRP levels in the four groups decreased significantly after treatment. The levels in the patients in the intestinal obstruction group decreased more markedly than in those in the other groups. There were positive correlations among the HCY level, PCT, and CRP before treatment only in patients with intestinal obstruction (P < 0.001). The difference was statistically significant in the HCY level between the non-operation and the operation groups in patients with intestinal obstruction (P < 0.001). Serum HCY may be a valuable marker for predicting aggravation of infection in patients with intestinal obstruction.

13.
Chem Sci ; 13(46): 13938-13947, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36544730

RESUMO

Investigating electrochemiluminescence (ECL) scenarios under different temperatures is important to expand its imaging scope near an electrode surface. Here, we develop a temperature-tuned ECL layer by recording the evolution of shadow regions of adherent cells. Finite element simulation and experimental results demonstrate that the thickness of the ECL layer (TEL) is reversibly regulated by electrode temperature (T e), so that single cell topography at different heights is imaged. The TEL in two ECL routes shows different regulation ranges with elevated T e, thus providing a flexible approach to adjust the imaging scope within specific heights. In addition, a heated electrode significantly improves the image quality of cell adhesion in heterogeneous electrochemical rate-determined situations. Thus, the contrast in cell regions shows a reversible response to T e. This work provides a new approach to regulate the TEL and is promising for monitoring transient heat generation from biological entities.

14.
Nat Commun ; 13(1): 7961, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575172

RESUMO

Construction of C-N bond continues to be one part of the most significant goals in organic chemistry because of the universal applications of amines in pharmaceuticals, materials and agrochemicals. However, E2 elimination through classic SN2 substitution of alkyl halides lead to generation of alkenes as major side-products. Thus, formation of a challenging C(sp3)-N bond especially on tertiary carbon center remains highly desirable. Herein, we present a practical alternative to prepare primary, secondary and tertiary alkyl amines with high efficiency between alkyl iodides and easily accessible diazonium salts. This robust transformation only employs Cs2CO3 promoting halogen-atom transfer (XAT) process under transition-metal-free reaction conditions, thus providing a rapid method to assemble diverse C(sp3)-N bonds. Moreover, diazonium salts served as alkyl radical initiator and amination reagent in the reaction. Mechanism studies suggest this reaction undergo through halogen-atom transfer process to generate active alkyl radical which couples with diazonium cations to furnish final products.

15.
Zhongguo Gu Shang ; 35(12): 1154-8, 2022 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-36572431

RESUMO

OBJECTIVE: To analyze relationship of debilitating and nutritional risk on complications of primary hip replacement, and risk factors of influence of complications of primary hip replacement. METHODS: Totally 100 patients who underwent hip replacement from January 2019 to January 2021 were retrospectively analyzed, including 36 males and 64 females, aged from 18 to 85 years old with an average of (73.82±4.04) years old. Postoperative frailty status was evaluated by modified frailty index, and nutritional status was evaluated by clinical biochemical indexes and NRS2002 nutritional risk assessment scale. One hundred patients were divided into frailty group and non-frailty group according to modified frailty index, 100 patients were divided into normal nutrition group and nutritional risk group according to nutritional status, and relationship between frailty, nutritional risk and complications after primary hip replacement was analyzed. RESULTS: There were significant differences in age, body mass index (BMI), complications and ASA grade between frailty group and non-frailty group(P<0.05). There were statistically significant differences in age, BMI, complications and ASA grade between normal nutrition group and nutritional risk group (P<0.05). Thirty-five patients occurred at least one postoperative complications, and the incidence of pulmonary infection was the highest, accounting for 34.29% (12/35). The second was urinary infection, accounting for 22.86%(8/35). Univariate Logistic regression analysis showed that age, BMI, ASA grade, complications, frailty and nutritional risk were the risk factors for postoperative complications. Multivariate Logistic regression analysis showed that complications, frailty and nutritional risk were independent factors affecting postoperative complications. CONCLUSION: Patients with comorbidities, frailty and nutritional risk could increase the incidence of complications. Timely assessment and identification of these patients in time, and formulation of targeted intervention measures have great clinical significance.


Assuntos
Artroplastia de Quadril , Complicações Pós-Operatórias , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Incidência , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
16.
Front Public Health ; 10: 1023022, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36582374

RESUMO

"Re-visits and drug renewal" is difficult for chronic disease patients during COVID-19 and will continue in the post-pandemic era. To overcome this dilemma, the scenario of chronic disease diagnosis and treatment systems was set, and an evolutionary game model participated by four stakeholder groups including physical medical institutions, medical service platforms, intelligent medical device providers, and chronic disease patients, was established. Ten possible evolutionary stabilization strategies (ESSs) with their mandatory conditions were found based on Lyapunov's first method. Taking cardiovascular and cerebrovascular diseases, the top 1 prevalent chronic disease, as a specific case context, and resorting to the MATLAB simulation, it is confirmed that several dual ESSs and four unique ESS circumstances exist, respectively, and the evolution direction is determined by initial conditions, while the evolution speed is determined by the values of the conditions based on the quantitative relations of benefits, costs, etc. Accordingly, four governance mechanisms were proposed. By their adjustment, the conditions along with their values can be interfered, and then the chronic disease diagnosis and treatment systems can be guided toward the desired direction, that is, toward the direction of countermeasure against the pandemic, government guidance, global trends of medical industry development, social welfare, and lifestyle innovation. The dilemma of "Re-visits and drug renewal" actually reflects the uneven distribution problem of qualified medical resources and the poor impact resistance capability of social medical service systems under mass public emergency. Human lifestyle even the way of working all over the world will get a spiral upgrade after experiencing COVID-19, such as consumption, and meeting, while medical habits react not so rapidly, especially for mid or aged chronic disease patients. We believe that telemedicine empowered by intelligent medical devices can benefit them and will be a global trend, governments and the four key stakeholders should act according to the governance mechanisms suggested here simultaneously toward novel social medical ecosystems for the post-pandemic era.


Assuntos
COVID-19 , Telemedicina , Humanos , Idoso , COVID-19/diagnóstico , COVID-19/epidemiologia , Ecossistema , Pandemias , Telemedicina/métodos , Doença Crônica
17.
Biomaterials ; 291: 121904, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36403323

RESUMO

Oxidative stress and mitochondrial damage are the main mechanisms of ischemia-reperfusion injury in ischemic stroke. Herein, cerium oxide nanoparticles with powerful free radical scavenging ability were used as carriers to load dl-3-n-butylphthalide (NBP-CeO2 NPs) for the combined treatment of ischemic stroke. NBP-CeO2 NPs could eliminate reactive oxygen species (ROS) in mouse brain microvascular endothelial cells and hippocampal neurons after oxygen-glucose deprivation/reoxygenation (OGD/R), and also save mitochondrial membrane potential, morphology, and function, thus alleviating the in vitro blood brain barrier (BBB) disruption and neuronal apoptosis. In the middle cerebral artery embolization/recanalization (MCAO/R) mouse model, the NBP-CeO2 NPs also possessed superior ROS scavenging ability, protected mitochondria, and preserved BBB integrity, thereby reducing cerebral infarction and cerebral edema and inhibiting neuroinflammation and neuronal apoptosis. The long-term neurobehavioral tests indicated that the NBP-CeO2 NPs significantly improved sensorimotor function and spatial learning ability by promoting angiogenesis after ischemic stroke. Therefore, the NBP-CeO2 NPs provided a novel therapeutic approach for ischemic stroke by combining antioxidant and neurovascular repair abilities, highlighting its wide application in ischemia-reperfusion injury.


Assuntos
AVC Isquêmico , Nanopartículas , Traumatismo por Reperfusão , Animais , Camundongos , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Espécies Reativas de Oxigênio , Células Endoteliais , Traumatismo por Reperfusão/tratamento farmacológico
18.
Nat Commun ; 13(1): 6588, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329065

RESUMO

The development of novel methodologies for the introduction of the sulfoxonium group under mild conditions is appealing but remains underexplored. Herein we report the synthesis of a class of hypervalent iodine reagents with a transferrable sulfoxonium group. These compounds enable mixed iodonium-sulfoxonium ylide reactivity. These well-defined reagents are examined in visible-light-promoted cyclization reactions with a wide range of unsaturated bonds including alkenes, alkynes, nitriles, and allenes. Two distinct cyclization pathways are identified, which are controlled by the substituent of the unsaturated bond. The cycloaddition protocol features simple operation, mild reaction conditions, and excellent functional group tolerance, affording a broad range of sulfoxonium-containing cyclic structures in moderate to excellent yields. Furthermore, the sufoxonium group in the product can be transformed into diverse functional groups and structural motifs via single electron transfer and transition-metal catalysis.

19.
J Nanobiotechnology ; 20(1): 466, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329465

RESUMO

Tumor phototheranostics holds a great promise on account of its high spatiotemporal resolution, tumor-specificity, and noninvasiveness. However, physical limitation of light penetration and "always on" properties of conventional photothermal-conversion agents usually cause difficulty in accurate diagnosis and completely elimination of tumor. Meanwhile, nanozymes mediated Fenton reactions can well utilize the tumor microenvironment (TME) to generate hydroxyl radicals for chemodynamic therapy (CDT), but limited by the concentration of H2O2 in TME and the delivery efficiency of nanozymes. To overcome these problems, a dual-targeting nanozyme (FTRNPs) is developed for tumor-specific in situ theranostics, based upon the assembling of ultrasmall Fe3O4 nanoparticles, 3,3',5,5'-tetrameth-ylbenzidine (TMB) and the RGD peptide. The FTRNPs after H2O2 treatment exhibits superior photothermal stability and high photothermal conversion efficiency (η = 50.9%). FTRNPs shows extraordinary accumulation and retention in the tumor site by biological/physical dual-targeting, which is 3.54-fold higher than that without active targeting. Cascade-dual-response to TME for nanozymes mediated Fenton reactions and TMB oxidation further improves the accuracy of both photoacoustic imaging and photothermal therapy (PTT). The tumor inhibition rate of photo-chemodynamic therapy is ~ 97.76%, which is ~ 4-fold higher than that of PTT or CDT only. Thus, the combination of CDT and PTT to construct "turn on" nanoplatform is of great significance to overcome their respective limitations. Considering its optimized "all-in-one" performance, this new nanoplatform is expected to provide an advanced theranostic strategy for the future treatment of cancers.


Assuntos
Nanopartículas , Neoplasias , Humanos , Medicina de Precisão , Peróxido de Hidrogênio , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Nanopartículas/química , Microambiente Tumoral , Linhagem Celular Tumoral
20.
Biomed Pharmacother ; 157: 114040, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36423545

RESUMO

Liver disease has become a major health problem worldwide due to its high morbidity and mortality. In recent years, a large body of literature has shown that mesenchymal stem cell-derived exosomes (MSC-Exo) are able to play similar physiological roles as mesenchymal stem cells (MSCs). More importantly, there is no immune rejection caused by transplanted cells and the risk of tumor formation, which has become a new strategy for the treatment of various liver diseases. Moreover, accumulating evidence suggests that non-coding RNAs (ncRNAs) are the main effectors by which they exert hepatoprotective effects. Therefore, by searching the databases of Web of Science, PubMed, ScienceDirect, Google Scholar and CNKI, this review comprehensively reviewed the therapeutic effects of MSC-Exo and ncRNAs in liver diseases, including liver injury, liver fibrosis, and hepatocellular carcinoma. According to the data, the therapeutic effects of MSC-Exo and ncRNAs on liver diseases are closely related to a variety of molecular mechanisms, including inhibition of inflammatory response, alleviation of liver oxidative stress, inhibition of apoptosis of hepatocytes and endothelial cells, promotion of angiogenesis, blocking the cell cycle of hepatocellular carcinoma, and inhibition of activation and proliferation of hepatic stellate cells. These important findings will provide a direction and basis for us to explore the potential of MSC-Exo and ncRNAs in the clinical treatment of liver diseases in the future.

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