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1.
J Org Chem ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38959135

RESUMO

A photoredox-promoted decarboxylative C-H glycosylation for the synthesis of nonclassical heteroaryl C-glycosides is reported. This methodology is characterized by an exceedingly simple reaction system, high diastereoselectivity, and good functional group tolerance. Moreover, the operational procedure is simple, and the gram-scale reaction highlights the practical applicability of this protocol.

2.
Eur J Med Chem ; 275: 116632, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38959726

RESUMO

Glucagon-like peptide-1 receptor (GLP-1R) is a pivotal receptor involved in blood glucose regulation and influencing feeding behavior. It has received significant attention in the treatment of obesity and diabetes due to its potent incretin effect. Peptide GLP-1 receptor agonists (GLP-1RAs) have achieved tremendous success in the market, driving the vigorous development of small molecule GLP-1RAs. Currently, several small molecules have entered the clinical research stage. Additionally, recent discoveries of GLP-1R positive allosteric modulators (PAMs) are also unveiling new regulatory patterns and treatment methods. This article reviews the structure and functional mechanisms of GLP-1R, recent reports on small molecule GLP-1RAs and PAMs, as well as the optimization process. Furthermore, it combines computer simulations to analyze structure-activity relationships (SAR) studies, providing a foundation for exploring new strategies for designing small molecule GLP-1RAs.

3.
Environ Monit Assess ; 196(7): 675, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951302

RESUMO

Vegetation is an important link between land, atmosphere, and water, making its changes of great significance. However, existing research has predominantly focused on long-term vegetation changes, neglecting the intra-annual variations of vegetation. Hence, this study is based on the Enhanced Vegetation Index (EVI) data from 2000 to 2022, with a time step of 16 days, to analyze the intra-annual patterns of vegetation changes in China. The average intra-annual EVI values for each municipal-level administrative region were calculated, and the time-series k-means clustering algorithm was employed to divide these regions, exploring the spatial variations in China's intra-annual vegetation changes. Finally, the ridge regression and random forest methods were utilized to assess the drivers of intra-annual vegetation changes. The results showed that: (1) China's vegetation status exhibits a notable intra-annual variation pattern of "high in summer and low in winter," and the changes are more pronounced in the northern regions than in the southern regions; (2) the intra-annual vegetation changes exhibit remarkable regional disparities, and China can be optimally clustered into four distinct clusters, which align well with China's temperature and precipitation zones; and (3) the intra-annual vegetation changes demonstrate significant correlations with meteorological factors such as dew point temperature, precipitation, maximum temperature, and sea-level pressure. In conclusion, our study reveals the characteristics, spatial patterns and driving forces of intra-annual vegetation changes in China, which contribute to explaining ecosystem response mechanisms, providing valuable insights for ecological research and the formulation of ecological conservation and management strategies.


Assuntos
Monitoramento Ambiental , Tecnologia de Sensoriamento Remoto , China , Estações do Ano , Plantas , Análise por Conglomerados , Ecossistema
4.
J Org Chem ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38952027

RESUMO

A visible-light-induced radical-radical cross-coupling reaction between 1,3,4-oxadiazoles and hydroxamic acid derivatives has been realized under base- and metal-free conditions. The protocol was characterized by broad substrate scope, excellent functional group tolerance, and simple operation procedures. By using this protocol, a variety of biologically important 5-aryl-1,3,4-oxadiazole-2-methylamines were obtained in good yields with excellent chemoselectivity.

5.
Int J Surg Case Rep ; 121: 109981, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38945016

RESUMO

INTRODUCTION AND IMPORTANCE: Oblique facial clefts are uncommon congenital facial deformities. Among them, Tessier No. 3 cleft is an even rare malformation. This study presents a reconstructive option and curative effect for oblique facial cleft deformity of Tessier No. 3. CASE PRESENTATION: A 10-year-old girl was admitted to our hospital with "congenital facial deformity of right nose and mid-face". The clinical diagnosis was "oblique facial cleft of Tessier classification No. 3", also known as "naso-orbital cleft". The cleft was surgically repaired with an adjacent flap and nasolabial flap. After surgery, the case underwent uneventful healing with a surviving flap, and the deformity was well repaired. At 3 months to 1 year of follow-up, the flap had a similar feature (color and texture) to the contralateral tissue. A good outcome was obtained with minimal scar and face deformity. CLINICAL DISCUSSION: Facial cleft is a clinical type of craniofacial cleft. The soft tissue feature of Tessier No. 3 cleft is that the fissure is located in the joint part of the middle nose, lateral nose, and maxillary process. The operation adopts the method of closing the fissure with soft tissue flap and pedicled flap transplantation is a priority method. In this clinical case, the patient with oblique facial cleft of Tessier classification No. 3 was repaired by the adjacent flap and nasolabial flap. CONCLUSION: The application of the adjacent flap and nasolabial flap is a viable option for the reconstruction of oblique facial cleft deformity of Tessier No. 3 in oral surgery.

6.
Sci Rep ; 14(1): 14686, 2024 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-38918459

RESUMO

Yuxi, located in China's central plateau of Yunnan, is grappling with ecological and environmental challenges as it continues to develop its economy. While ecological quality assessment serves as the foundation for ecological protection, it is pivotal to have reliable and long-term methods for assessing the ecological status to support informed decision-making in ecological protection. Reliable and long-term methods for assessing ecological status in order to facilitate informed decision-making in ecological protection are applied. This study utilized Landsat data to reconstruct four indices (greenness, wetness, dryness, and heat) during the vegetation growth in Yuxi from 2000 to 2020 that employs Harmonic Analysis of Time Series (HANTS) method. Subsequently, the annual Remote Sensing Ecological Index (RSEI) was computed by using the reconstructed indices to evaluate ecological quality in Yuxi. Additionally, spatiotemporal patterns and determinants of Yuxi's ecological quality are unveiled through Sen's slope estimator and Mann-Kendall test (Sen + MK) trend analysis, spatial auto-correlation analysis, and geographical detectors applied to year-by-year RSEI data. The findings in the paper indicate that the accuracy of the RSEI is significantly influenced by the vegetation season, suggesting that constructing the RSEI model with data from the vegetation growth season is crucial. Moreover, the HANTS optimization method effectively enhances the ecological indices used in the RSEI model, leading to smoother and more continuous filling of missing data. The difference between the reconstructed RSEI and the original RSEI falls within the range of - 0.15 to 0.15. Yuxi has an average RSEI of 0.54 to emphasis a moderate level of comprehensive ecological quality. Compared with river valley plains, the ecological quality of mountainous areas is higher, and the ecological quality of Yuxi presents a distinct center-edge pattern. From 2000 to 2020, Yuxi's ecological quality exhibited fluctuations, with a slight overall improvement. Land use patterns, particularly in forestry land and impervious surfaces, are identified as the main drivers of these changes. The research offers valuable insights for scientific decision-making related to sustainable development and ecological protection.


Assuntos
Estações do Ano , China , Tecnologia de Sensoriamento Remoto , Monitoramento Ambiental/métodos , Análise Espaço-Temporal , Ecossistema , Conservação dos Recursos Naturais/métodos , Desenvolvimento Vegetal , Ecologia/métodos
7.
ACS Omega ; 9(24): 26112-26120, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38911748

RESUMO

Molecules with both aggregation-induced emission (AIE) and thermally activated delayed fluorescence (TADF) properties are potential organic light-emitting diode materials; however, the AIE and TADF mechanisms are still debatable. In this work, four molecules incorporating carbazole (Cz), phenoxazine (PXZ), and phenothiazine (PTZ) as donor groups to the diphenylsulfone acceptor were investigated. The experiment results indicate that a molecule containing Cz exhibits solely TADF properties, whereas molecules containing PXZ and PTZ demonstrate both TADF and AIE characteristics. As for DPS-PTZ, the result indicates that the thin-film environment restricts molecular twisting, consequently reducing nonradiative decay, thereby attributing to the AIE property by density functional theory and molecular dynamics simulation. As for DPS-PXZ, the result suggests that the restricted access to a conical intersection in a singlet excited via an expansion in the C-S-C angle is the pivotal factor for the AIE characteristic. The C-S-C angle twist of DPS-PXZ is impeded in the aggregate state and resulted in luminescence. Understanding the mechanisms serves as a valuable guide for the development of new AIE systems, enabling their application in various practical domains.

8.
Adv Sci (Weinh) ; : e2400953, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885424

RESUMO

The thermal runaway issue represents a long-standing obstacle that retards large-scale applications of lithium metal batteries. Various approaches to inhibit thermal runaway suffer from some intrinsic drawbacks, either being irreversible or delayed thermal protection. Herein, this work has explored thermo-responsive lower critical solution temperature (LCST) ionic liquid-based electrolytes, which provides reversible overheating protection for batteries with warning and shut-down stages, well corresponding to an initial stage of thermal runaway process. The batteries could function stably below 70 °C as a working mode, while demonstrating a warning mode above 80 °C with a noticeable reduction in specific capacitance to delay temperature increase of batteries. In terms of 110 °C as a critically dangerous temperature, a shut-down mode is designed to minimize the thermal energy releasing as the batteries are barely chargeable and dischargeable. Dynamically growing polymeric particles above LCST contributed to such an intelligent and mild control on specific capacitance. Larger size will occupy larger surfaces of electrodes and close more pores of separators, enabling a gradual suppressing of Li+ transfer and reactions. The present work demonstrated a scientific design of thermoresponsive LCST electrolytes with a superiorly precise and intelligent control of electrochemical performances to achieve self-adapted overheating protections.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38904627

RESUMO

Background: Cough variant asthma is a prevalent condition among children with chronic cough, significantly impacting their health and well-being. Objective: This study aimed to assess the impact of spleen aminopeptide oral lyophilized powder and fluticasone/salmeterol powder inhaler on pulmonary function and the incidence of adverse reactions in children with cough variant asthma. Methods: A total of 60 children with cough variant asthma admitted to the Pediatric Department of Cangzhou Central Hospital between July 2019 and June 2020 were enrolled in the study. Using the random number table method, they were assigned to either the observation group or the control group, with 30 cases in each group. The control group received treatment with fluticasone/salmeterol powder inhalers, while the observation group received a combination of fluticasone/salmeterol powder inhalers and spleen aminopeptide oral lyophilized powder. After 8 weeks of treatment, various clinical parameters, including forced vital capacity, forced expiratory volume per second/forced vital capacity, peak expiratory flow, fractional exhaled nitric oxide (FeNO), interleukin-4 (IL-4), IL-10, eosinophils in induced sputum, and serum CD4+ and CD8+ levels, were compared between the two groups. Results: The observation group exhibited a higher total effective rate of clinical efficacy compared to the control group [90.00% vs. 63.33%; OR (95% CI) 3.00 (1.01-8.92), P = .048)]. After 8 weeks, the observation group demonstrated higher levels of forced vital capacity, forced expiratory volume per second/forced vital capacity, peak expiratory flow [OR (95% CI) 0.48 (0.26-0.88), P = .017; OR (95% CI) 0.29 (0.14-0.57) 2.57 (1.46-4.52) 0.33 (0.16-0.70), P = .000, .001, .003], IL-10 [OR (95% CI) 0.29 (0.14-0.57), P = .000], and lower levels of FeNO [OR (95% CI) 0.48 (0.26-0.88), P = .017], IL-4, and eosinophils [OR (95% CI) 2.57 (1.46-4.52) 0.33 (0.16-0.70), P = .001, .003] compared to the control group (P < .05). Furthermore, the observation group exhibited higher levels of CD4+ and CD4+/CD8+ compared to the control group [OR (95% CI) 0.41 (0.25-0.67) 0.33 (0.20-0.56) 1.73 (1.18-2.55), P = .000, .000, .001]. Computed tomography measurements revealed significantly lower airway wall thickness, basement membrane thickness, and total airway wall area in the observation group compared to the control group [OR (95% CI) 0.18 (0.10-0.33) 0.23 (0.13-0.41) 0.28 (0.15-0.51), P = .000, .000, .000]. The incidence of adverse reactions did not significantly differ between the groups (6.67% vs. 3.33%; P > .05). Conclusion: The combination treatment of spleen aminopeptide oral lyophilized powder and fluticasone/salmeterol powder inhaler effectively improves lung function, FeNO levels, and airway inflammation, while enhancing cellular and humoral immune function in children with cough variant asthma. These findings have significant clinical implications and warrant further promotion and application of this treatment approach.

10.
Angew Chem Int Ed Engl ; : e202406407, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862386

RESUMO

The design of admire hydrogel networks is of both practical and fundamental importance for diverse applications of hydrogels. Herein a general strategy of acid-assisted training is designed to enable multiple improvement of conventional poly (sodium acrylate) networks for hydrogels. Hydrophobic homogeneous crosslinked poly (sodium acrylate) hydrogels are prepared to verify the strategy. The acid-assisted training is simply achieved by immersing the hydrogel networks into 4 M H2SO4 solutions. The introduced acids would induce transformation of poly (sodium acrylate) into poly (acrylic acid) at hydrogel surface, which constructs dynamic hydrogen bonding interactions to tighten the network. The acid-containing poly (sodium acrylate) hydrogels newly generate anti-swelling and self-healing performance, and show mechanical improvement. The internal poly (sodium acrylate) of the pristine acid-containing hydrogels is further fully transformed via acid-infiltration after following cyclic stretch/release training to significantly improve the mechanical performance. The Young's modulus, stress, and toughness of the fully-trained hydrogels are 187.6 times, 35.6 times, and 5.4 times enhanced, respectively. The polymeric networks retain isotropic in fully-trained hydrogels to ensure superior stretchability of 8.6. The acid-assisted training performance of the hydrogels can be reversibly recovered by NaOH neutralization. The acid-assisted training strategy here is general for poly (sodium acrylate) hydrogels.

11.
Urol J ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38863317

RESUMO

PURPOSE: Chromosome 7 open reading frame 61 (C7orf 61) was a testis-specific gene, and may be involved in the process of spermatogenesis. This study was aimed to investigate the expression of C7orf61 in the testis and determine its role in spermatogenesis. Materials and Medhods: Reverse transcription-quantitative polymerase chain reaction, Western blot and immunofluorescence were performed to evaluate the expression characteristics of C7orf61 in mice and humans. In vitro fertilization assay was used to determine the role of the C7ORF61 protein in sperm-egg fusion. RESULTS: The results demonstrated that C7orf61 was a testis-specific gene; the C7ofr61 mRNA expression level sharply increased in the fourth postnatal week and gradually increased until the adult stage. The C7ORF61 protein was located throughout the subacrosomal area and close to the nucleus in both mouse and human sperm. The incubation with the C7ORF61 antibody significantly decreased the fertilization rate of mouse eggs. CONCLUSION: The present findings suggested that the C7ORF61 protein might be involved in sperm-egg fusion, and could serve as a useful target for contraceptives. However, further research is still needed to know the detailed molecular mechanism of its role.

12.
Foot Ankle Surg ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38853037

RESUMO

BACKGROUND: Solely relying on the tibial ankle surface (TAS) angle for determining the mechanical ankle axis might be insufficient. We introduce a novel method to determine the distance from the center of the talus to the tibial axis (TTD). This study aimed to investigate the association between clinical outcomes and radiological changes before and after supramalleolar osteotomy (SMO), including TAS angle, talar tilt (TT) angle, tibiotalar surface (TTS) angle and TTD. METHODS: Seventy patients who received SMO were enrolled. Radiological changes were measured using weight-bearing anteroposterior imaging. The percentage of talar center displacement (TTDP) was calculated as the difference between postoperative and preoperative TTD, divided by talar width (TW). Clinical assessments were performed using the American Orthopedic Foot and Ankle Society ankle-hindfoot (AOFAS) scale. Differences in the aforementioned indicators before and after the operation were analyzed. We defined ΔAOFAS, ΔTAS, ΔTT and ΔTTS as the difference between postoperative and preoperative values. RESULTS: ΔTTS correlated with ΔAOFAS (r = 0.40, p = 0.008), as did TTDP (r = 0.32, p = 0.035). No correlation was observed between ΔAOFAS and ΔTAS. In the comparison between groups, patients with a TTDP greater than 26.19 exhibited a significantly greater ΔAOFAS. The high intraclass correlation coefficient indicated good reliability of the novel method. CONCLUSION: Solely relying on the TAS angle for tibial correction was insufficient. We found TTD as a novel method to evaluate mechanical ankle joint axis. TTDP and ΔTTS both positively correlated with ΔAOFAS, indicating the usefulness of these radiologic parameters.

13.
Phys Rev E ; 109(5-1): 054312, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38907474

RESUMO

The Brain Connectome Project has made significant strides in uncovering the structural connections within the brain on various levels. This has led to the question of how brain structure and function are related. Our research explores this relationship in an adaptive neural network in which synaptic conductance between neurons follows spike-time synaptic plasticity rules. By adjusting the plasticity boundary, the network exhibits diverse collective behaviors, including phase synchronization, phase locking, hierarchical synchronization (phase clusters), and coexisting states. Using graph theory, we found that hierarchical synchronization is related to the community structure, while coexisting states are related to the hierarchical self-organizing and core-periphery structure. The network evolves into several tightly connected modules, with sparsely intermodule connections resulting in the formation of phase clusters. In addition, the hierarchical self-organizing structure facilitates the emergence of coexisting states. The coexistence state promotes the evolution of the core-periphery structure. Our results point towards the equivalence between function and structure, with function emerging from structure, and structure being influenced by function in a complex dynamic process.

14.
Analyst ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874099

RESUMO

Persistent luminescent nanoparticles (PLNPs) are excellent luminescent materials, and near-infrared PLNPs are efficiently applied for biosensing and bioimaging due to their advantages of no excitation, excellent light stability and long afterglow. However, due to interference from the complex environment within organisms, single-mode imaging methods often face limitations in selectivity, sensitivity, and accuracy. Therefore, it is desirable to construct a dual-mode imaging probe strategy with higher specificity and sensitivity for bioimaging. Magnetic resonance imaging (MRI) has been widely used in the field of bioimaging due to its advantages of high resolution, non-radiation and non-invasiveness. Here, by combining near-infrared PLNPs and manganese dioxide (MnO2) nanosheets, a sensitive and convenient dual-mode "turn on" bioimaging nanoprobe ZGC@MnO2 has been developed for long afterglow imaging and MRI of endogenous hydrogen peroxide (H2O2) in the tumor microenvironment (TME). The monitoring of H2O2 has garnered significant attention due to its crucial role in human pathologies. For the dual-mode "turn on" bioimaging nanoprobe, the near-infrared PLNPs of quasi-spherical ZnGa2O4:Cr (ZGC) nanoparticles were synthesized as luminophores, and MnO2 nanosheets were utilized as a fluorescence quencher, carrier and H2O2 recognizer. H2O2 in the TME could reduce MnO2 nanosheets to Mn2+ for MRI, and ZGC nanoparticles were released for long afterglow imaging. Finally, the ZGC@MnO2 nanoprobe exhibited a rapid response, an excellent signal-to-noise ratio and a limit of detection of 3.67 nM for endogenous H2O2 in the TME. This dual-mode approach enhances the detection sensitivity for endogenous H2O2, thereby facilitating the research of endogenous H2O2-associated diseases and clinical diagnostics.

15.
Adv Sci (Weinh) ; : e2404269, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874326

RESUMO

Artificial light-harvesting systems (LHSs) with a multi-step sequential energy transfer mechanism significantly enhance light energy utilization. Nonetheless, most of these systems exhibit an overall energy transfer efficiency below 80%. Moreover, due to challenges in molecularly aligning multiple donor/acceptor chromophores, systems featuring ≥3-step sequential energy transfer are rarely reported. Here, a series of artificial LHSs is introduced featuring up to 4-step energy transfer mechanism, constructed using a cyclic peptide-based supramolecular scaffold. These LHSs showed remarkably high energy transfer efficiencies (≥90%) and satisfactory fluorescence quantum yields (ranging from 17.6% to 58.4%). Furthermore, the structural robustness of the supramolecular scaffold enables a comprehensive study of these systems, elucidating the associated energy transfer pathways, and identifying additional energy transfer processes beyond the targeted sequential energy transfer. Overall, this comprehensive investigation not only enhances the understanding of these LHSs, but also underscores the versatility of cyclic peptide-based supramolecular scaffolds in advancing energy harvesting technologies.

16.
J Pharm Biomed Anal ; 247: 116268, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823222

RESUMO

Methotrexate (MTX) is commonly prescribed as the initial treatment for gestational trophoblastic neoplasia (GTN), but MTX monotherapy may not be effective for high-risk GTN and choriocarcinoma. The cellular uptake of MTX is essential for its pharmacological activity. Thus, our study aimed to investigate the cellular pharmacokinetics and transport mechanisms of MTX in choriocarcinoma cells. For the quantification of MTX concentrations in cellular matrix, a liquid chromatography-tandem mass spectrometry method was created and confirmed initially. MTX accumulation in BeWo, JEG-3, and JAR cells was minimal. Additionally, the mRNA levels of folate receptor α (FRα) and breast cancer resistance protein (BCRP) were relatively high in the three choriocarcinoma cell lines, whereas proton-coupled folate transporter (PCFT), reduced folate carrier (RFC), and organic anion transporter (OAT) 4 were low. Furthermore, the expression of other transporters was either very low or undetectable. Notably, the application of inhibitors and small interfering RNAs (siRNAs) targeting FRα, RFC, and PCFT led to a notable decrease in the accumulation of MTX in BeWo cells. Conversely, the co-administration of multidrug resistance protein 1 (MDR1) and BCRP inhibitors increased MTX accumulation. In addition, inhibitors of OATs and organic-anion transporting polypeptides (OATPs) reduced MTX accumulation, while peptide transporter inhibitors had no effect. Results from siRNA knockdown experiments and transporter overexpression cell models indicated that MTX was not a substrate of nucleoside transporters. In conclusion, the results indicate that FRα and multiple transporters such as PCFT, RFC, OAT4, and OATPs are likely involved in the uptake of MTX, whereas MDR1 and BCRP are implicated in the efflux of MTX from choriocarcinoma cells. These results have implications for predicting transporter-mediated drug interactions and offer potential directions for further research on enhancing MTX sensitivity.


Assuntos
Coriocarcinoma , Metotrexato , Espectrometria de Massas em Tandem , Metotrexato/farmacologia , Humanos , Coriocarcinoma/metabolismo , Coriocarcinoma/tratamento farmacológico , Espectrometria de Massas em Tandem/métodos , Linhagem Celular Tumoral , Transporte Biológico , Cromatografia Líquida/métodos , Feminino , Proteínas de Neoplasias/metabolismo , Antimetabólitos Antineoplásicos/farmacologia , Antimetabólitos Antineoplásicos/farmacocinética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/metabolismo , Gravidez , Receptor 1 de Folato/metabolismo , Receptor 1 de Folato/genética , RNA Interferente Pequeno , Proteína Carregadora de Folato Reduzido/metabolismo , Proteína Carregadora de Folato Reduzido/genética , Espectrometria de Massa com Cromatografia Líquida
17.
J Am Chem Soc ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38924516

RESUMO

We report a general and functional-group-tolerant method for the Cu-catalyzed amination of base-sensitive aryl bromides including substrates possessing acidic functional groups and small five-membered heteroarenes. The results presented herein substantially expand the scope of Cu-catalyzed C-N coupling reactions. The combination of L8, an anionic N1,N2-diarylbenzene-1,2-diamine ligand, along with the mild base NaOTMS leads to the formation of a stable yet reactive catalyst that resists deactivation from coordination to heterocycles or charged intermediates. This system enables the use of low catalyst and ligand loadings. Exploiting the differences in nucleophile deprotonation in C-O and C-N coupling reactions catalyzed by Cu·L8 we developed a method to chemoselectively N- and O-arylate a variety of amino alcohol substrates. Employing NaOt-Bu as the base resulted exclusively in C-O coupling when the amino alcohols featured primary alcohols and more hindered amines or aniline groups. Utilizing NaOTMS enabled the ability to override the steric-based selectivity of these reactions completely and exclusively promoted C-N coupling regardless of the structure of the amino alcohol. The ability to invert the observed chemoselectivity is distinct from previously described methods that require protecting group manipulations or rely entirely on steric effects to control reactivity. These results substantially improve the scope of Cu-catalyzed C-N coupling reactions using N1,N2-diarylbenzene-1,2-diamine ligands and introduce a new chemoselective method to arylate amino alcohols.

18.
Biomed Pharmacother ; 176: 116869, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38850665

RESUMO

OBJECTIVE: Integrated stress response (ISR) is activated to promote cell survival by maintaining the phosphorylation of eukaryotic translation initiation factor 2 (eIF2α). We investigated whether Sephin1 enhances ISR and attenuates myocardial ischemia-reperfusion (MIR) injury. METHODS: Male C57BL/6 J mice were injected with Sephin1 (2 mg/kg,i.p.) 30 min before surgery to establish a model of MIR with 45 min ischemia and 180 min reperfusion. In vitro, the H9C2 cell line with hypoxia-reoxygenation (H/R) was used to simulate MIR. Myocardial injury was evaluated by echocardiography, histologic observation after staining with TTC and H&E and electron microscopy. ISR, autophagy and apoptosis in vivo and in vitro were evaluated by immunoblotting, immunohistochemistry, immunofluorescence, and flow cytometry, respectively. Global protein synthesis was determined using a non-radioactive SUnSET Assay based on the puromycin method. Autophinib, an autophagy-specific inhibitor, was used to investigate the correlation between autophagy and apoptosis in the presence of Sephin1. RESULTS: In vivo, Sephin1 significantly reduced myocardial injury and improved the cardiac function in MIR mice. Sephin1 administration prolonged ISR, reduced cell apoptosis, and promoted autophagy. In vitro, Sephin1 increased the number of stress granules (SGs) and autophagic vesicles, enhanced ISR and related protein synthesis suppression, and reduced cell apoptosis. Autophinib partly reversed autophagosome formation and apoptosis in H9c2 cells. CONCLUSIONS: Sephin1 enhances ISR and related protein synthesis suppression, ameliorates myocardial apoptosis, and promotes autophagy during MIR stress. Sephin1 could act as a noval ISR enhancer for managing acute myocardial ischemia disease.


Assuntos
Apoptose , Autofagia , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão Miocárdica , Animais , Autofagia/efeitos dos fármacos , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Camundongos , Apoptose/efeitos dos fármacos , Linhagem Celular , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Modelos Animais de Doenças , Eritropoetina , Fragmentos de Peptídeos
19.
Int J Biol Macromol ; 271(Pt 1): 132472, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38772455

RESUMO

The two most active disulfide bond isomers of the analgesic αO-conotoxin GeXIVA, namely GeXIVA[1, 2] and GeXIVA[1, 4], were subjected to Asp-scanning mutagenesis to determine the key amino acid residues for activity at the rat α9α10 nicotinic acetylcholine receptor (nAChR). These studies revealed the key role of arginine residues for the activity of GeXIVA isomers towards the α9α10 nAChR. Based on these results, additional analogues with 2-4 mutations were designed and tested. The analogues [T1A,D14A,V28K]GeXIVA[1, 2] and [D14A,I23A,V28K]GeXIVA[1, 4] were developed and showed sub-nanomolar activity for the α9α10 nAChR with IC50 values of 0.79 and 0.38 nM. The latter analogue had exceptional selectivity for the α9α10 receptor subtype over other nAChR subtypes and can be considered as a drug candidate for further development. Molecular dynamics of receptor-ligand complexes allowed us to make deductions about the possible causes of increases in the affinity of key GeXIVA[1, 4] mutants for the α9α10 nAChR.


Assuntos
Arginina , Ácido Aspártico , Conotoxinas , Receptores Nicotínicos , Conotoxinas/química , Conotoxinas/genética , Conotoxinas/farmacologia , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Receptores Nicotínicos/química , Animais , Arginina/química , Ratos , Ácido Aspártico/química , Ácido Aspártico/genética , Antagonistas Nicotínicos/química , Antagonistas Nicotínicos/farmacologia , Simulação de Dinâmica Molecular , Mutagênese , Isomerismo
20.
Drug Des Devel Ther ; 18: 1743-1754, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38803562

RESUMO

Purpose: Remimazolam tosilate is a novel ultrafast-acting benzodiazepine that has a rapid emergence even after continuous infusion when using flumazenil. So far, relatively few articles are still focusing on the quality of recovery after general anesthesia with remimazolam, especially in day surgery. This study aimed to compare the early postoperative quality of recovery of remimazolam tosilate with flumazenil and propofol in patients undergoing day surgery. Patients and Methods: 137 patients scheduled for day surgery were randomly divided into the remimazolam tosilate or propofol group. The primary endpoint was the incidence of overall recovery assessed with the early postoperative quality of recovery scale (PostopQRS) on postoperative day 1 (POD 1). The Richmond Agitation-Sedation Scale (RASS) scores in the post-anesthesia care unit (PACU), extubation time, postoperative recovery profiles, and perioperative data were documented. Any adverse events were recorded. Results: The incidence of overall recovery on POD1 was 47.7% in the remimazolam tosilate group and 65.1% in the propofol group (odds ratio, 0.52; 95% confidence interval (CI) 0.26 to 1.06; P = 0.072). In general, the overall recovery of the PostopQRS increased over time, and its interaction between time and group was significant (P = 0.003). Among the five dimensions of PostopQRS, there exist statistical differences between groups including emotional state and cognitive recovery. Upon arrival at the PACU, the remimazolam group was more sedated and took longer to recover to a RASS score similar to propofol. The frequency of application of vasoactive drugs during anesthesia was similar in both groups (P = 0.119). Despite rapid emergence with remimazolam after flumazenil reversal, re-sedation (10.8%) or somnolence (60%) in the PACU was observed, and the length of PACU stay in patients treated with remimazolam tosilate was longer than that of the propofol (35 min vs 30 min, P<0.001). Conclusion: General anesthesia with remimazolam tosilate in conjunction with flumazenil reversal permits rapid recovery of consciousness in day surgery, but there was a notable occurrence of re-sedation or somnolence observed in PACU.


Assuntos
Benzodiazepinas , Hipnóticos e Sedativos , Propofol , Humanos , Propofol/administração & dosagem , Feminino , Masculino , Estudos Prospectivos , Pessoa de Meia-Idade , Benzodiazepinas/administração & dosagem , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/farmacologia , Adulto , Procedimentos Cirúrgicos Ambulatórios , Período de Recuperação da Anestesia , Idoso , Flumazenil/administração & dosagem , Flumazenil/farmacologia , Flumazenil/uso terapêutico
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