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1.
Diabetologia ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958700

RESUMO

AIMS/HYPOTHESIS: Strategies to augment functional beta cell mass include directed differentiation of stem cells towards a beta cell fate, which requires extensive knowledge of transcriptional programs governing endocrine progenitor cell differentiation in vivo. We aimed to study the contributions of the Brahma-related gene-1 (BRG1) and Brahma (BRM) ATPase subunits of the SWI/SNF chromatin remodelling complex to endocrine cell development. METHODS: We generated mice with endocrine progenitor-specific Neurog3-Cre BRG1 removal in the presence of heterozygous (Brg1Δendo;Brm+/-) or homozygous (double knockout: DKOΔendo) BRM deficiency. Whole-body metabolic phenotyping, islet function characterisation, islet quantitative PCR and histological characterisation were performed on animals and tissues postnatally. To test the mechanistic actions of SWI/SNF in controlling gene expression during endocrine cell development, single-cell RNA-seq was performed on flow-sorted endocrine-committed cells from embryonic day 15.5 control and mutant embryos. RESULTS: Brg1Δendo;Brm+/- mice exhibit severe glucose intolerance, hyperglycaemia and hypoinsulinaemia, resulting, in part, from reduced islet number; diminished alpha, beta and delta cell mass; compromised islet insulin secretion; and altered islet gene expression programs, including reductions in MAFA and urocortin 3 (UCN3). DKOΔendo mice were not recovered at weaning; however, postnatal day 6 DKOΔendo mice were severely hyperglycaemic with reduced serum insulin levels and beta cell area. Single-cell RNA-seq of embryonic day 15.5 lineage-labelled cells revealed endocrine progenitor, alpha and beta cell populations from SWI/SNF mutants have reduced expression of Mafa, Gcg, Ins1 and Ins2, suggesting limited differentiation capacity. Reduced Neurog3 transcripts were discovered in DKOΔendo endocrine progenitor clusters, and the proliferative capacity of neurogenin 3 (NEUROG3)+ cells was reduced in Brg1Δendo;Brm+/- and DKOΔendo mutants. CONCLUSIONS/INTERPRETATION: Loss of BRG1 from developing endocrine progenitor cells has a severe postnatal impact on glucose homeostasis, and loss of both subunits impedes animal survival, with both groups exhibiting alterations in hormone transcripts embryonically. Taken together, these data highlight the critical role SWI/SNF plays in governing gene expression programs essential for endocrine cell development and expansion. DATA AVAILABILITY: Raw and processed data for scRNA-seq have been deposited into the NCBI Gene Expression Omnibus (GEO) database under the accession number GSE248369.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38696085

RESUMO

PURPOSE: We developed a novel augmented fluoroscopy-guided intrathoracic stamping technique for localizing small pulmonary nodules in the hybrid operating room. We conducted an observational study to investigate the feasibility of this technique and retrospectively compared two augmented fluoroscopy-guided approaches: intrathoracic and transbronchial. METHODS: From August 2020 to March 2023, consecutive patients underwent single-stage augmented fluoroscopy-guided localization under general anaesthesia. This included intrathoracic stamping and bronchoscopic lung marking, followed by thoracoscopic resection in a hybrid operating room. Comparative analyses were performed between the two groups. RESULTS: The data of 50 patients in the intrathoracic stamping and 67 patients in the bronchoscopic lung marking groups were analysed. No significant difference was noted in demographic data between the groups, except a larger lesion depth in the bronchoscopic lung marking group (14.7 ± 11.7 vs 11.0 ± 5.8 mm, p = 0.029). Dye localization was successfully performed in 49 intrathoracic stamping group patients (98.0%) and 67 bronchoscopic lung marking group patients (100%). No major procedure-related complications occurred in either group; however, the time flow (total anaesthesia time/global operating room time) was longer, and the radiation exposure (fluoroscopy duration/total dose area product) was larger in the bronchoscopic lung marking group. CONCLUSIONS: Augmented fluoroscopic stamping localization under intubated general anaesthesia is feasible and safe, providing an alternative with less global operating room time and lower radiation exposure for image-guided thoracoscopic surgery in the hybrid operating room.

3.
ACS Catal ; 14(10): 7707-7716, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38779184

RESUMO

Nonthermal plasma (NTP) offers the potential for converting CH4 with CO2 into liquid products under mild conditions, but controlling liquid selectivity and manipulating intermediate species remain significant challenges. Here, we demonstrate the effectiveness of the Cu/UiO-66-NH2 catalyst in promising the conversion of CH4 and CO2 into oxygenates within a dielectric barrier discharge NTP reactor under ambient conditions. The 10% Cu/UiO-66-NH2 catalyst achieved an impressive 53.4% overall liquid selectivity, with C2+ oxygenates accounting for ∼60.8% of the total liquid products. In situ plasma-coupled Fourier-transform infrared spectroscopy (FTIR) suggests that Cu facilitates the cleavage of surface adsorbed COOH species (*COOH), generating *CO and enabling its migration to the surface of Cu particles. This surface-bound *CO then undergoes C-C coupling and hydrogenation, leading to ethanol production. Further analysis using CO diffuse reflection FTIR and 1H nuclear magnetic resonance spectroscopy indicates that in situ generated surface *CO is more effective than gas-phase CO (g) in promoting C-C coupling and C2+ liquid formation. This work provides valuable mechanistic insights into C-C coupling and C2+ liquid production during plasma-catalytic CO2 oxidation of CH4 under ambient conditions. These findings hold broader implications for the rational design of more efficient catalysts for this reaction, paving the way for advancements in sustainable fuel and chemical production.

4.
J Colloid Interface Sci ; 669: 816-824, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38749220

RESUMO

The precise and controllable preparation of carbon nanomaterials under mild conditions poses a great challenge, especially for metal-catalysed multiphase preparation. This work proposes an efficient method that utilizing high-density ultrasound to enhance the liquid-liquid interfacial reaction system. Iron-doped carbon dots (Fe-CDs) are successfully synthesized in such a normal temperature and atmospheric-pressure reaction condition. It is shown that transient cavitation provides a high-temperature and high-pressure microenvironment for the preparation of Fe-CDs. Moreover, the size of the reactant droplets is reduced from 200.0 ± 17.3 µm to 8.1 ± 2.9 µm owing to the acoustic flow and cavitation effects, which increases the specific surface area of the two reacting phases and improves the mass transfer coefficient by more than 252.0 %. As a result, the yield increases by more than an order of magnitude (from 0.7 ± 0.1 % to 11.9 ± 0.2 %) and the Fe doping rate reaches 20.9 %. The photocatalytic oxidation conversion of 1,4-Dihydropyridine (1,4-DHP) using the obtained Fe-CDs is as high as 98.2 %. This research gives a new approach for the efficient and safe production of Fe-CDs, which is promising for industrial applications.

5.
Toxicology ; 505: 153830, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38754619

RESUMO

The use of tyrosine kinase inhibitors (TKIs) has resulted in significant occurrence of arrhythmias. However, the precise mechanism of the proarrhythmic effect is not fully understood. In this study, we found that nilotinib (NIL), vandetanib (VAN), and mobocertinib (MOB) induced the development of "cellrhythmia" (arrhythmia-like events) in a concentration-dependent manner in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). Continuous administration of NIL, VAN, or MOB in animals significantly prolonged the action potential durations (APD) and increased susceptibility to arrhythmias. Using phosphoproteomic analysis, we identified proteins with altered phosphorylation levels after treatment with 3 µM NIL, VAN, and MOB for 1.5 h. Using these identified proteins as substrates, we performed kinase-substrate enrichment analysis to identify the kinases driving the changes in phosphorylation levels of these proteins. MAPK and WNK were both inhibited by NIL, VAN, and MOB. A selective inhibitor of WNK1, WNK-IN-11, induced concentration- and time-dependent cellrhythmias and prolonged field potential duration (FPD) in hiPSC-CMs in vitro; furthermore, administration in guinea pigs confirmed that WNK-IN-11 prolonged ventricular repolarization and increased susceptibility to arrhythmias. Fingding indicated that WNK1 inhibition had an in vivo and in vitro arrhythmogenic phenotype similar to TKIs. Additionally,three of TKIs reduced hERG and KCNQ1 expression at protein level, not at transcription level. Similarly, the knockdown of WNK1 decreased hERG and KCNQ1 protein expression in hiPSC-CMs. Collectively, our data suggest that the proarrhythmic effects of NIL, VAN, and MOB occur through a kinase inhibition mechanism. NIL, VAN, and MOB inhibit WNK1 kinase, leading to a decrease in hERG and KCNQ1 protein expression, thereby prolonging action potential repolarization and consequently cause arrhythmias.


Assuntos
Potenciais de Ação , Arritmias Cardíacas , Miócitos Cardíacos , Piperidinas , Proteômica , Pirimidinas , Quinazolinas , Humanos , Arritmias Cardíacas/induzido quimicamente , Animais , Proteômica/métodos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Piperidinas/farmacologia , Piperidinas/toxicidade , Pirimidinas/toxicidade , Pirimidinas/farmacologia , Quinazolinas/toxicidade , Quinazolinas/farmacologia , Potenciais de Ação/efeitos dos fármacos , Inibidores de Proteínas Quinases/toxicidade , Inibidores de Proteínas Quinases/farmacologia , Fosforilação , Canal de Potássio ERG1/metabolismo , Canal de Potássio ERG1/antagonistas & inibidores , Canal de Potássio ERG1/genética , Cobaias , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Canal de Potássio KCNQ1/metabolismo , Canal de Potássio KCNQ1/genética , Canal de Potássio KCNQ1/efeitos dos fármacos , Fosfoproteínas/metabolismo , Relação Dose-Resposta a Droga
6.
Artigo em Inglês | MEDLINE | ID: mdl-38619440

RESUMO

BACKGROUND: Lupus erythematosus (LE) is a spectrum of autoimmune diseases. Due to the complexity of cutaneous LE (CLE), clinical skin image-based artificial intelligence is still experiencing difficulties in distinguishing subtypes of LE. OBJECTIVES: We aim to develop a multimodal deep learning system (MMDLS) for human-AI collaboration in diagnosis of LE subtypes. METHODS: This is a multi-centre study based on 25 institutions across China to assist in diagnosis of LE subtypes, other eight similar skin diseases and healthy subjects. In total, 446 cases with 800 clinical skin images, 3786 multicolor-immunohistochemistry (multi-IHC) images and clinical data were collected, and EfficientNet-B3 and ResNet-18 were utilized in this study. RESULTS: In the multi-classification task, the overall performance of MMDLS on 13 skin conditions is much higher than single or dual modals (Sen = 0.8288, Spe = 0.9852, Pre = 0.8518, AUC = 0.9844). Further, the MMDLS-based diagnostic-support help improves the accuracy of dermatologists from 66.88% ± 6.94% to 81.25% ± 4.23% (p = 0.0004). CONCLUSIONS: These results highlight the benefit of human-MMDLS collaborated framework in telemedicine by assisting dermatologists and rheumatologists in the differential diagnosis of LE subtypes and similar skin diseases.

7.
ACS Appl Mater Interfaces ; 16(13): 16340-16350, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38511525

RESUMO

As an additive for perovskites, in addition to functional groups, the steric configuration of molecules is worthy of consideration because it influences perovskite crystallization, thus determining whether defect passivation is effective without any side effects. In this work, the chiral molecules l- and d-pyroglutamic acid (l-PA and d-PA) were chosen as additives for perovskite passivators to reveal the reasons for the differences in passivation between amino acids with different steric configurations. Functional groups, such as the C═O groups and N-H groups of l-PA and d-PA, can passivate the perovskite defects. However, l-PA exhibited a more distorted steric configuration, while d-PA was more planar, leading to differences in the distances between the two C═O groups. Taking the Pb-Pb bond length as a reference, the shorter distance between the two C═O groups of l-PA distorts the perovskite lattice structure, which results in poor device stability. Conversely, the similar distance between the two C═O groups of d-PA promoted the preferred orientational growth of the perovskite. Finally, the d-PA-doped device accomplished an excellent efficiency of 24.11% with an improved open-circuit voltage of 1.17 V. Furthermore, the efficiency of the unencapsulated d-PA-doped device was maintained at 93% in N2 for more than 3000 h and 74% after 500 h of operation at maximum power point tracking under continuous illumination.

8.
J Org Chem ; 89(3): 2014-2023, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38241168

RESUMO

A Pd-catalyzed dual C-H carbonylation of commercially available diarylamines using Co2(CO)8 as a safe CO source has been developed. This methodology provides a facile approach for the synthesis of diversified acridones in moderate to good yields. The protocol features good functional group compatibility, operational safety, easy scale-up, and versatile transformations.

9.
J Am Chem Soc ; 146(1): 578-585, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38157440

RESUMO

Biofunctionalized conjugated polymers (i.e., carrying enzymes, antibodies, and nucleic acids) are of great interest for many biological applications, yet efficient biofunctionalization of conjugated polymers under biocompatible conditions is challenging. We report a facile strategy to make biofunctionalized conjugated polymers through thiol-ene chemistry with embedded latent disulfide functional groups. This is made possible through the design of a cyclic disulfide-containing dioxythiophene, which can be integrated into a series of conjugated polymers via acid-catalyzed chain-growth polymerization. The utility of such a biofunctionalized polymer with glucose oxidase has been examined in organic electrochemical transistors for the selective sensing of glucose. This work provides a venue for the creation of biofunctional organic semiconductors.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38047886

RESUMO

Nanozyme-induced reactive oxygen species (ROS)-dependent catalytic therapy has been developed into a powerful strategy against bacterial wound infections. However, the limited endogenous supply or instability of H2O2, the reliance on external stimuli for the generation of ROS, and the highly expressed glutathione (GSH) level make it a challenge to achieve high-performance therapeutic efficiency. In this work, a facile therapeutic strategy against bacterial infections with pristine CuFe layered double hydroxide (LDH) as the self-cascade nanoreactor is proposed without modification or additional energy input. CuFe LDH with an oxidase-like feature can catalyze the generation of multiple ROS, such as 1O2, ·O2-, and H2O2. And the self-generated H2O2 in the cascade nanoreactor could be further in situ transformed to ·OH owing to the peroxidase-like activity. As a result, the cell membrane of bacteria is destroyed, leading to death. Furthermore, its ultrahigh enzyme-like activity of CuFe LDH could effectively promote the breakdown of the biofilm structure. Additionally, the Cu2+-mediated GSH exhaustion of CuFe LDH further avoids the consumption of oxidized ROS and thereby significantly improves the sterilization effect. Finally, the as-prepared CuFe LDH with negligible side effects on normal tissues can be successfully used to eliminate the methicillin-resistant Staphylococcus aureus-infected wounds and accelerate their healing in the mouse model, which paves a new avenue as an antibacterial agent for clinical anti-infective treatment.

11.
bioRxiv ; 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38106138

RESUMO

Histone deacetylase inhibitors (HDIs) modulate ß cell function in preclinical models of diabetes; however, the mechanisms underlying these beneficial effects have not been determined. In this study, we investigated the impact of the HDI sodium butyrate (NaB) on ß cell function and calcium (Ca2+) signaling using ex vivo and in vitro models of diabetes. Our results show that NaB significantly improved glucose-stimulated insulin secretion in islets from human organ donors with type 2 diabetes and in cytokine-treated INS-1 ß cells. Consistently, NaB partially rescued glucose-stimulated Ca2+ oscillations in mouse islets treated with proinflammatory cytokines. Because the oscillatory phenotype of Ca2+ in the ß cell is governed by changes in endoplasmic reticulum (ER) Ca2+ levels, next we explored the relationship between NaB and store-operated calcium entry (SOCE), a rescue mechanism that acts to refill ER Ca2+ levels through STIM1-mediated gating of plasmalemmal Orai channels. We found that NaB treatment preserved basal ER Ca2+ levels and restored SOCE in IL-1ß-treated INS-1 cells. Furthermore, we linked these changes with the restoration of STIM1 levels in cytokine-treated INS-1 cells and mouse islets, and we found that NaB treatment was sufficient to prevent ß cell death in response to IL-1ß treatment. Mechanistically, NaB counteracted cytokine-mediated reductions in phosphorylation levels of key signaling molecules, including AKT, ERK1/2, glycogen synthase kinase-3α (GSK-3α), and GSK-3ß. Taken together, these data support a model whereby HDI treatment promotes ß cell function and Ca2+ homeostasis under proinflammatory conditions through STIM1-mediated control of SOCE and AKT-mediated inhibition of GSK-3.

12.
J Dermatolog Treat ; 34(1): 2279899, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38010938

RESUMO

Immunoglobulin gamma (IgG) type 4-related disease (IgG4-RD) is a chronic immunologic systemic disorder that could affect multiple organs, which may cause irreversible organ damage or even death. Skin involvement is rare and associated especially with systemic disease. The dermatologist must be equipped to recognize IgG4-RD to prevent delayed identification and treatment. This case reports a very rare case of IgG4-related skin disease (IgG4-RSD) presenting with a generalized angiolymphoid hyperplasia with eosinophilia (ALHE)-like lesions in a middle-aged male patient with no other organ involvement. He was treated with oral glucocorticoid and cyclophosphamide, which resulted in complete remission. No relapse and disease progression were seen with a follow-up for 8 years.


Assuntos
Hiperplasia Angiolinfoide com Eosinofilia , Doença Relacionada a Imunoglobulina G4 , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Angiolinfoide com Eosinofilia/patologia , Hiperplasia Angiolinfoide com Eosinofilia/terapia , Ciclofosfamida/uso terapêutico , Seguimentos , Glucocorticoides/uso terapêutico , Imunoglobulina G , Doença Relacionada a Imunoglobulina G4/complicações
13.
Zhongguo Zhong Yao Za Zhi ; 48(18): 5068-5077, 2023 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-37802849

RESUMO

This study investigated the drug delivery performance of oral co-loaded puerarin(PUE) and daidzein(DAZ) mixed micelles(PUE/DAZ-FS/PMMs) from the perspectives of pharmacokinetics, pharmacodynamics, and tissue distribution. The changes in PUE plasma concentration in rats were evaluated based on PUE suspension, single drug-loaded micelles(PUE-FS/PMMs), and co-loaded micelles(PUE/DAZ-FS/PMMs). Spontaneously hypertensive rats(SHR) were used to monitor systolic blood pressure, diastolic blood pressure, and mean arterial pressure for 10 weeks after administration by tail volume manometry. The content of PUE in the heart, liver, spleen, lung, kidney, brain, and testes was determined using LC-MS/MS. The results showed that compared with PUE suspension and PUE-FS/PMMs, PUE/DAZ-FS/PMMs significantly increased C_(max) in rats(P<0.01) and had a relative bioavailability of 122%. The C_(max), AUC_(0-t), AUC_(0-∞), t_(1/2), and MRT of PUE/DAZ-FS/PMMs were 1.77, 1.22, 1.22, 1.17, and 1.13 times higher than those of PUE suspension, and 1.76, 1.16, 1.08, 0.84, and 0.78 times higher than those of PUE-FS/PMMs, respectively. Compared with the model control group, PUE/DAZ-FS/PMMs significantly reduced systolic blood pressure, diastolic blood pressure, and mean arterial pressure in SHR rats(P<0.05). The antihypertensive effect of PUE/DAZ-FS/PMMs was greater than that of PUE suspension, and even greater than that of PUE-FS/PMMs at high doses. Additionally, the distribution of PMMs in various tissues showed dose dependency. The distribution of PMMs in the kidney and liver, which are metabolically related tissues, was lower than that in the suspension group, while the distribution in the brain was higher than that in the conventional dose group. In conclusion, PUE/DAZ-FS/PMMs not only improved the bioavailability of PUE and synergistically enhanced its therapeutic effect but also prolonged the elimination of the drug to some extent. Furthermore, the micelles facilitated drug penetration through the blood-brain barrier. This study provides a foundation for the development of co-loaded mixed micelles containing homologous components.


Assuntos
Isoflavonas , Micelas , Ratos , Animais , Distribuição Tecidual , Cromatografia Líquida , Espectrometria de Massas em Tandem , Ratos Endogâmicos SHR , Isoflavonas/farmacologia
14.
Front Pharmacol ; 14: 1236656, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601055

RESUMO

Background: The unique pharmaceutical methods for the processing of botanical drugs according to the theory of traditional Chinese medicine (TCM) affect clinical syndrome differentiation and treatment. The objective of this study was to comprehensively elucidate the principles and mechanisms of an herbal processing method by investigating the alterations in the metabolites of Rhizoma Atractylodis Macrocephalae (AMR) processed by Aurantii Fructus Immaturus (AFI) decoction and to determine how these changes enhance the efficacy of aqueous extracts in treating functional dyspepsia (FD). Methods: A qualitative analysis of AMR before and after processing was conducted using UPLC-Q-TOF-MS/MS, and HPLC was employed for quantitative analysis. A predictive analysis was then conducted using a network analysis strategy to establish a botanical drug-metabolite-target-disease (BMTD) network and a protein-protein interaction (PPI) network, and the predictions were validated using an FD rat model. Results: A total of 127 metabolites were identified in the processed AMR (PAMR), and substantial changes were observed in 8 metabolites of PAMR after processing, as revealed by the quantitative analysis. The enhanced aqueous extracts of processed AMR (PAMR) demonstrate improved efficacy in treating FD, which indicates that this processing method enhances the anti-inflammatory properties and promotes gastric motility by modulating DRD2, SCF, and c-kit. However, this enhancement comes at the cost of attenuating the regulation of motilin (MTL), gastrin (GAS), acetylcholine (Ach), and acetylcholinesterase (AchE). Conclusion: Through this series of investigations, we aimed to unravel the factors influencing the efficacy of this herbal formulation in improving FD in clinical settings.

15.
Diabetes ; 72(10): 1433-1445, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37478155

RESUMO

Altered endoplasmic reticulum (ER) Ca2+ signaling has been linked with ß-cell dysfunction and diabetes development. Store-operated Ca2+ entry replenishes ER Ca2+ through reversible gating of plasma membrane Ca2+ channels by the ER Ca2+ sensor, stromal interaction molecule 1 (STIM1). For characterization of the in vivo impact of STIM1 loss, mice with ß-cell-specific STIM1 deletion (STIM1Δß mice) were generated and challenged with high-fat diet. Interestingly, ß-cell dysfunction was observed in female, but not male, mice. Female STIM1Δß mice displayed reductions in ß-cell mass, a concomitant increase in α-cell mass, and reduced expression of markers of ß-cell maturity, including MafA and UCN3. Consistent with these findings, STIM1 expression was inversely correlated with HbA1c levels in islets from female, but not male, human organ donors. Mechanistic assays demonstrated that the sexually dimorphic phenotype observed in STIM1Δß mice was due, in part, to loss of signaling through the noncanonical 17-ß estradiol receptor (GPER1), as GPER1 knockdown and inhibition led to a similar loss of expression of ß-cell maturity genes in INS-1 cells. Together, these data suggest that STIM1 orchestrates pancreatic ß-cell function and identity through GPER1-mediated estradiol signaling. ARTICLE HIGHLIGHTS: Store-operated Ca2+ entry replenishes endoplasmic reticulum (ER) Ca2+ through reversible gating of plasma membrane Ca2+ channels by the ER Ca2+ sensor, stromal interaction molecule 1 (STIM1). ß-Cell-specific deletion of STIM1 results in a sexually dimorphic phenotype, with ß-cell dysfunction and loss of identity in female but not male mice. Expression of the noncanonical 17-ß estradiol receptor (GPER1) is decreased in islets of female STIM1Δß mice, and modulation of GPER1 levels leads to alterations in expression of ß-cell maturity genes in INS-1 cells.


Assuntos
Canais de Cálcio , Proteínas de Membrana , Animais , Camundongos , Feminino , Humanos , Proteínas de Membrana/metabolismo , Canais de Cálcio/metabolismo , Molécula 1 de Interação Estromal/genética , Molécula 1 de Interação Estromal/metabolismo , Cálcio/metabolismo , Receptores de Estradiol/metabolismo , Receptor alfa de Estrogênio/metabolismo , Sinalização do Cálcio , Proteínas de Ligação ao GTP/metabolismo
16.
Angew Chem Int Ed Engl ; 62(36): e202304699, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37409373

RESUMO

Developing new reactive pathway to activate inert C(sp3 )-H bonds for valuable oxygenated products remains a challenge. We prepared a series of triazine conjugated organic polymers to photoactivate C-H into aldehyde/ketone via O2 →H2 O2 →⋅OH→Cl⋅→Cl2 ⋅- . Experiment results showed Cl2 ⋅- could successively activate C(sp3 )-H more effectively than Cl⋅ to generate unstable dichlorinated intermediates, increasing the kinetic rate ratio of dichlorination to monochlorination by a factor of 2,000 and thus breaking traditional dichlorination kinetic constraints. These active intermediates were hydrolyzed into aldehydes or ketones easily, when compared with typical stable dichlorinated complexes, avoiding chlorinated by-product generation. Moreover, an integrated two-phase system in an acid solution strengthened the Cl2 ⋅- mediated process and inhibited product overoxidation, where the conversion rate of toluene reached 16.94 mmol/g/h and the selectivity of benzaldehyde was 99.5 %. This work presents a facile and efficient approach for selective conversion of inert C(sp3 )-H bonds using Cl2 ⋅- .

17.
Ultrason Sonochem ; 95: 106411, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37098312

RESUMO

Ag2S quantum dots (QDs) have aroused extensive concerns in intravital imaging field due to their merits of narrow bandgap, low biological toxicity and decent fluorescence emission properties in the second near-infrared (NIR-II) window. However, low quantum yield (QY) and poor uniformity of Ag2S QDs are still main obstacles for its application. In this work, a novel strategy of utilizing ultrasonic field is presented, which can enhance the microdroplet-based interfacial synthesis of Ag2S QDs. The ultrasound increases the presence of ions at the reaction sites by enhancing the ion mobility in the microchennels. Therefore, the QY is enhanced from 2.33 % (optimal QY without ultrasound) to 8.46 %, which is the highest value of Ag2S ever reported without ion-doping. Also, the decrease of the corresponding full width at half maximum (FWHM) from 312 nm to 144 nm indicates the obvious uniformity improvement of the obtained QDs. Further mechanism exploration illustrates that ultrasonic cavitation significantly increases the interfacial reaction sites by splitting the droplets. Meanwhile, the acoustic flow field strengthens the ion renewal at the droplet interface. Consequently, the mass transfer coefficient increases by more than 500 %, which is favorable to improve both the QY and quality of Ag2S QDs. This work serves both fundamental research and practical production for the synthesis of Ag2S QDs.

18.
Zhongguo Zhong Yao Za Zhi ; 48(3): 579-587, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36872220

RESUMO

Traditional Chinese medicine(TCM) has a long history and abundant experience in external therapy, which marks human wisdom. In the early history of human, people found that fumigation, coating, and sticking of some tree branches and herb stems can help alleviate scabies and remove parasites in productive labor, which indicates the emergence of external therapy. Pathogen usually enters the body through the surface, so external therapy can be used to treat the disease. External therapy is among the major characteristic of surgery of TCM. As one of the external therapies in TCM, external application to acupoints smooths the zang-fu organs through meridians and collaterals, thereby harmonizing yin and yang. This therapy emerged in the early society, formed the Spring and Autumn Period and the Warring States Period, improved in the Song and Ming dynasties, and matured in the Qing dynasty. With the efforts of experts in history, it has had a mature theory. According to modern research, it can avoid the first-pass effect of liver and the gastrointestinal irritation and improve the bioavailability of Chinese medicine. Based on the effect of Chinese medicine and the theory of meridian and collateral, it can stimulate the acupoints, exert regulatory effect on acupoints, and give full play to the efficacy of TCM and the interaction of the two. Thereby, it can regulate qi and blood and balance yin and yang, thus being widely used in the treatment of diseases. In this paper, the use of external application to acupoints, the effect on skin immunity, the regulation of neuro-inflammatory mechanism, the relationship between acupoint application and human circulation network, and the development of its dosage form were summarized through literature review. On this basis, this study is expected to lay a foundation for further research.


Assuntos
Pontos de Acupuntura , Meridianos , Humanos , Disponibilidade Biológica , Fumigação , Medicina Tradicional Chinesa
19.
Biomater Adv ; 149: 213390, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36963249

RESUMO

The development of fascinating materials with functional properties has revolutionized the humankind with materials comfort, stopped the spreading of diseases, relieving the environmental pollution pressure, economized government research funds, and prolonged their serving life. The outbreak of Coronavirus Disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has triggered great global public health concern. Face masks are crucial tools to impede the spreading of SARS-CoV-2 from human to human. However, current face masks exhibit in a variety of colors (opaque), like blue, black, red, etc., leading to a communication barrier between the doctor and the deaf-mute patient when wearing a mask. High optical transparency filters can be utilized for both personal protection and lip-reading. Thus, shaping face air filter into a transparent appearance is an urgent need. Electrospinning technology, as a mature technology, is commonly used to form nanofiber materials utilizing high electrical voltage. With the alteration of the diameters of nanofibers, and proper material selection, it would be possible to make the transparent face mask. In this article, the research progress in the transparent face air filter is reviewed with emphasis on three parts: mechanism of the electrospinning process and light transmission, preparation of transparent face air filter, and their innovative potential. Through the assessment of classic cases, the benefits and drawbacks of various preparation strategies and products are evaluated, to provide general knowledge for the needs of different application scenarios. In the end, the development directions of transparent face masks in protective gear, particularly their novel functional applications and potential contributions in the prevention and control of the epidemic are also proposed.


Assuntos
Filtros de Ar , COVID-19 , Nanofibras , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Filtração
20.
Diabetes ; 72(6): 746-757, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36913741

RESUMO

The transcriptional activity of Pdx1 is modulated by a diverse array of coregulatory factors that govern chromatin accessibility, histone modifications, and nucleosome distribution. We previously identified the Chd4 subunit of the nucleosome remodeling and deacetylase complex as a Pdx1-interacting factor. To identify how loss of Chd4 impacts glucose homeostasis and gene expression programs in ß-cells in vivo, we generated an inducible ß-cell-specific Chd4 knockout mouse model. Removal of Chd4 from mature islet ß-cells rendered mutant animals glucose intolerant, in part due to defects in insulin secretion. We observed an increased ratio of immature-to-mature insulin granules in Chd4-deficient ß-cells that correlated with elevated levels of proinsulin both within isolated islets and from plasma following glucose stimulation in vivo. RNA sequencing and assay for transposase-accessible chromatin with sequencing showed that lineage-labeled Chd4-deficient ß-cells have alterations in chromatin accessibility and altered expression of genes critical for ß-cell function, including MafA, Slc2a2, Chga, and Chgb. Knockdown of CHD4 from a human ß-cell line revealed similar defects in insulin secretion and alterations in several ß-cell-enriched gene targets. These results illustrate how critical Chd4 activities are in controlling genes essential for maintaining ß-cell function. ARTICLE HIGHLIGHTS: Pdx1-Chd4 interactions were previously shown to be compromised in ß-cells from human donors with type 2 diabetes. ß-Cell-specific removal of Chd4 impairs insulin secretion and leads to glucose intolerance in mice. Expression of key ß-cell functional genes and chromatin accessibility are compromised in Chd4-deficient ß-cells. Chromatin remodeling activities enacted by Chd4 are essential for ß-cell function under normal physiological conditions.


Assuntos
Cromatina , Diabetes Mellitus Tipo 2 , Camundongos , Animais , Humanos , Cromatina/genética , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Diabetes Mellitus Tipo 2/genética , DNA Helicases/genética , Camundongos Knockout , Expressão Gênica , Glucose
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