[Analysis of 14 cases of sarcoidosis of head and neck].

Objective:To explore the clinical characteristics of sarcoidosis of head and neck symptoms, and to summarize the diagnosis and treatment experience. Methods:A retrospective study was conducted on patients with nodular disease with main symptoms in the head and neck who visited Henan Provincial People's Hospital from January 2020 to August 2023. The clinical data including symptom characteristics, pathological characteristics, treatment methods, and prognosis were analyzed. Results:A total of 14 patients were included, with 4 males（28.6%） and 10 females（71.4%）, age ranged from 11 to 71 years, with an average age of（52.0±15.8） years. The lesions were located in the parotid gland in 2 cases and the neck in 12 cases. Twelve cases underwent neck mass resection surgery, and 2 cases underwent ultrasound-guided core biopsy of parotid gland tumor and postoperative pathological diagnosis was confirmed in all cases. Four cases received steroid treatment postoperatively, and showed good prognosis with reduced lesion size after 3 months. Three cases did not take medication and the lesions continued to persist, causing discomfort. Seven cases did not take medication postoperatively, and the lesions expanded with multi-organ progression. Conclusion:Patients with head and neck sarcoidosis are rare in clinical practice, and it is prone to misdiagnosis and missed diagnosis. Steroid therapy can achieve good therapeutic effects.

Impact of sodium-glucose cotransporter 2 inhibitor on recurrence and cardiovascular outcomes after catheter ablation for atrial fibrillation in patients with heart failure.

BACKGROUND: The impact of sodium-glucose cotransporter 2 inhibitors (SGLT2i) on atrial fibrillation (AF) recurrence outcomes and adverse cardiovascular outcomes in heart failure (HF) patients after AF ablation is unknown. OBJECTIVE: We investigated whether SGLT2i reduces the risk of AF recurrence and adverse cardiovascular outcomes in HF patients after AF ablation. METHODS: HF patients with AF undergoing catheter ablation between January 2017 and December 2022 from the China-AF Registry were included. Patients were stratified into 2 groups on the basis of the use of SGLT2i at discharge and were 1:1 matched by propensity score, with SGLT2i using (n = 368) and non-SGLT2i using (n = 368) in each group. The primary outcome was AF recurrence after a 3-month blanking period. RESULTS: During a total of 1315 person-years of follow-up, AF recurred in 83 patients (22.6%) in the SGLT2i group and 132 patients (35.8%) in the non-SGLT2i group. SGLT2i was associated with a lower risk of AF recurrence (adjusted hazard ratio, 0.56; 95% CI, 0.43-0.74; P < .001). The composite risk of cardiovascular death, thrombotic events, or cardiovascular hospitalization was significantly lower in the SGLT2i group compared with those without SGLT2i (adjusted hazard ratio, 0.58; 95% CI, 0.41-0.80; P = .001). Although there was a trend toward benefit, the differences in all-cause mortality, cardiovascular death, or thrombotic events were insignificant between the 2 groups. CONCLUSION: The use of SGLT2i was associated with a lower risk of AF recurrence and the composite outcome of cardiovascular death, thrombotic events, or cardiovascular hospitalization after catheter ablation for AF in patients with HF.

Double C-H Amination of Naphthylamine Derivatives by the Cross-Dehydrogenation Coupling Reaction.

A high-efficiency tandem process has been developed for the formation of two C-N bonds through a cross-dehydrogenative coupling (CDC) amination of spiro[acridine-9,9'-fluorene]s (SAFs) with amines. This method offers a strategically innovative and atom-economical approach to obtaining diamine-substituted SAFs. Notably, the approach eliminates the need for metal catalysts and other additives, relying solely on O2 as the oxidant. A self-activation mechanism has been proposed to elucidate the effective double amination in the CDC process.

MiR-33a-5p in stored red blood cells regulates genes of innate immune response and promotes inflammation.

BACKGROUND AND OBJECTIVES: Blood transfusion is a common therapeutic procedure in hospitalized patients. Red blood cell (RBC) units undergo various biochemical and morphological changes during storage (storage lesion). miRNAs have been studied intensively regarding cellular metabolic processes, but the effect of miRNAs on blood storage is not well defined. MATERIALS AND METHODS: We performed bioinformatics analysis on the public data set of miRNA expression of RBC based on R language, and performed the Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis on the target genes of differentially expressed miRNA. The expression of miRNA differential genes in blood samples stored at different times was verified by qRT-PCR. Next, we used ELISA and qRT-PCR to verify the expression of IL-1ß, IL-6, IL-12 and TNF-α in blood at day 1 and day 42. In addition, in vitro, we transfected macrophages with overexpressed miRNA, and the effects of overexpressed miRNA on macrophage polarization and the release of inflammatory factors were verified by flow cytometry and qRT-PCR and ELISA. RESULTS: This study combined bioinformatics analysis and experiments to discover the differentially expressed miRNAs in long-term stored blood. The results showed that compared to fresh blood samples, the inflammatory factors were significantly doubled by ELISA, as well as the higher mRNA expression at 42 day. Experimentally verified that miR-33a-5p promoted the M1 type macrophage polarization and increased the release of related inflammatory factors through PPARα/ACC2/AMPK/CPT-1a axis regulation. CONCLUSIONS: This study elucidates a potential mechanism of inflammatory factor accumulation in long-term stored blood, providing a theoretical basis and a potential target to prevent transfusion-related adverse reactions.

Identification and Functional Characterization of a Surfactant-like Protein Region in Flagellin FliC for Stabilizing Selenium Nanoparticles and Enhancing Bioavailability.

Biogenic selenium nanoparticles (SeNPs) are the most favorable Se form for nutritional supplementation due to their high stability, low toxicity, and high activity. However, the interaction between the surface-binding proteins and their stable biogenic SeNPs, as well as their impact on the stability and bioavailability of SeNPs, remains to be understood. In vitro stabilization experiments revealed an amino acid segment (F(235-386)) in Rahnella aquatilis' flagellin FliC, with surfactant-like properties, stabilizing SeNPs under harsh conditions. FliC and F(235-386) were employed as stabilizers to synthesize SeNPs (FliC@SeNPs and F(235-386)@SeNPs), and surface chemistry analysis revealed coordination reactions between the proteins and Se atoms on the surface of SeNPs. Both FliC and F(235-386) enhanced SeNPs uptake in wheat seedlings but reduced it in bacteria and yeast. This study highlights FliC's core function in stabilizing SeNPs and enhancing their bioavailability, paving the way for agricultural and nutritional applications.

Fluorination modification enhanced the water resistance of Universitetet i Oslo-67 for multiple volatile organic compounds adsorption under high humidity conditions: Mechanism study.

The construction of metal-organic frameworks (MOFs) with highly efficient capture for volatile organic compounds (VOCs) adsorption under humid conditions is a significant yet formidable task. Herein, series of fluorinated UiO-67 modified with trifluoroacetic acid (TFA) and 4-fluorobenzoic acid were successfully synthesized for VOCs adsorption under high humidity conditions. Experiments results showed that UiO-67 modified with 4-fluorobenzoic acid (67-F) presented excellent adsorption capacity of 345 mg/g for toluene adsorption and exhibited great water resistance (10.0 vol% H2O, 374 mg/g toluene adsorption capacity). Characterization results indicated that the introduction of 4-fluorobenzoic acid induced the competitive coordination between 4-fluorobenzoic acid and 4,4-biphenyl dicarboxylic acid (BPDC) with Zr4+, causing the formation of abundant defects to provide extra adsorption sites. Meanwhile, the benzene ring in 4-fluorobenzoic acid enhanced the π-π conjugation, causing the further promotion of VOCs adsorption capacity. More importantly, the water resistance mechanism was investigated and elucidated that the introduction of F decreased the surface energy of 67-F and its affinity with water. Meanwhile, the metal complex induced by the fluorinated modification produced an electron-dense pore environment, which greatly improved its chemical and water stability. This work provided a strategy for preparing an adsorbent with high water resistance for real-world VOCs adsorption at high humidity conditions.

Insight into the Critical Role of Oxygen Vacancies and V=O Bonds Length in V2O5 for Advanced Zinc Ion Storage.

Due to the larger sizes and stronger positive polarity of Zn2+ than dominant univalent ions, Zn2+ sluggish diffusion within V2O5 host electrodes is an essential issue in developing aqueous zinc-ion batteries (ZIBs) of higher energy densities. Herein, a high-performance V2O5 cathode was developed through subtly synthesizing and tuning V2O5 with oxygen vacancies-enriched and elongated apical V=O1 bond by altering the gradient concentration of hydrazine hydrate in the gas-solid reaction system. This strategy can enhance both intrinsic and extrinsic conductivity to a large extent. The electrochemical testing demonstrated the oxygen vacancies-enriched and elongated apical V=O1 bond can not only increase the intrinsic electronic conductivity of V2O5, but also induce additional pseudocapacitance to enhance the Zn2+ diffusion kinetics. We used infrared spectroscopy and Raman spectroscopy to characterize the change in the bond length structure of V2O5. Simultaneously, the long-term cyclability (capacity retention of 76.9 % after 1200 cycles at 4.0 A g-1) and rate capabilities (218 mAh g-1 at 4.0 A g-1) are promoted as well. We believe that our work might shed light on the bond length engineering of V2O5 and provide insights for the reasonable designing of novel cathodes for practical rechargeable ZIBs.

Characteristics and outcome of patients with left atrial appendage closure in China: a single-center experience.

BACKGROUND: Clinical characteristics and long-term data on the safety and efficacy of LAAC in preventing cerebrovascular accident and thromboembolism among Chinese patients with non-valvular AF (NVAF) remain limited. METHODS: Data of consecutive NVAF patients who underwent LAAC at Beijing Anzhen Hospital, Capital Medical University, from June 1, 2014, to December 31, 2021, were collected and analyzed retrospectively. The primary effectiveness endpoint was the composite endpoint of stroke/transient ischemic attack, systemic embolism, and death from cardiovascular causes. The primary safety endpoint is the severe bleeding defined by the LAAC Munich consensus. RESULTS: Of the 222 patients enrolled, the mean age was 66.90 ± 9.62 years, with a majority being male (77.03%). Many patients are non-paroxysmal AF (71.19%) with a median duration of AF of 4.00 years. The mean CHA2DS2-VASc score was 3.78 ± 1.49, and the mean HAS-BLED score was 1.68 ± 0.86. Thromboembolic events (76.58%) were the most common indication for LAAC. The device, technical, and procedural success rates were 98.65%, 98.65%, and 93.69%, respectively. The anticoagulation continuation rate was 56.36%, 31.25%, and 22.60% at 3-, 6- and 12 months post-procedure, respectively. Throughout a mean 2.81 years of follow-up, the incidence of the primary efficacy endpoint was 4.27 per 100 patient-years, predominantly attributable to stroke/TIA (3.12 per 100 PYs). Five patients experienced major bleeding during the follow-up period. Post-procedure imaging revealed minimal complications, with only one substantial peri-device leak. Device-related thrombus occurred in 2.33% of patients, resolving with anticoagulation. CONCLUSION: The study demonstrates that LAAC is a safe and effective alternative option for Chinese patients with AF, with a high success rate, few complications as well as fewer long-term adverse outcome events.

Clinical and Genomic Characteristics of a Clinical Listeria Monocytogenes ST120 Isolate Recovered from a Pregnant Woman.

Background: Maternal-fetal listeriosis, caused by Listeria monocytogenes, is a rare but serious infection. Herein, we report the clinical and genomic characteristics of a clinical L. monocytogenes ST120 isolate recovered from a pregnant woman. Methods: The clinical symptoms and treatment in pregnant woman were described in detail. Whole genome sequencing (WGS) was performed on the L. monocytogenes isolate SJZ_LM001, and the genomic characterization of the isolate was deeply analyzed. Results: The clinical symptoms in pregnant women were mainly fever, and the placenta experienced severe inflammation. The pregnant woman was treated with ampicillin for effective anti-infective therapy. Genomic analysis showed that isolate SJZ_LM001 is sequence type (ST) 120, belong to clonal complex (CC)8 and lineage II of L. monocytogenes. Additionally, the isolates SJZ_LM001 harbored a novel plasmid pSJZ_LM001, which carried arsenical resistance genes (arsACD and acr3), and cadmium resistance genes (cadAC). Drug susceptibility testing showed that the isolate SJZ-LM001 was susceptible to ampicillin, meropenem, penicillin, and cotrimoxazole. Conclusion: This is the first to identify a clinical case of infection in a pregnant woman caused by ST120 L. monocytogenes in China. These findings could benefit our understanding of the genomic characteristics of L. monocytogenes, and the pregnancy-related listeriosis and providing early diagnosis and effective targeted treatment.

Coplanar Conformational Structure of π-Conjugated Polymers for Optoelectronic Applications.

Hierarchical structure of conjugated polymers is critical to dominating their optoelectronic properties and applications. Compared to nonplanar conformational segments, coplanar conformational segments of conjugated polymers (CPs) demonstrate favorable properties for applications as a semiconductor. Herein, recent developments in the coplanar conformational structure of CPs for optoelectronic devices are summarized. First, this review comprehensively summarizes the unique properties of planar conformational structures. Second, the characteristics of the coplanar conformation in terms of optoelectrical properties and other polymer physics characteristics are emphasized. Five primary characterization methods for investigating the complanate backbone structures are illustrated, providing a systematical toolbox for studying this specific conformation. Third, internal and external conditions for inducing the coplanar conformational structure are presented, offering guidelines for designing this conformation. Fourth, the optoelectronic applications of this segment, such as light-emitting diodes, solar cells, and field-effect transistors, are briefly summarized. Finally, a conclusion and outlook for the coplanar conformational segment regarding molecular design and applications are provided.

Amorphous structure and crystal stability determine the bioavailability of selenium nanoparticles.

Microorganisms play a critical role in the biogeochemical cycling of selenium, often reducing selenite/selenate to elemental selenium nanoparticles (SeNPs). These SeNPs typically exist in an amorphous structure but can transform into a trigonal allotrope. However, the crystal structural transition process and its impact on selenium bioavailability have not been well studied. To shed light on this, we prepared chemosynthetic and biogenic SeNPs and investigated the stability of their crystal structure. We found that biogenic SeNPs exhibited a highly stable amorphous structure in various conditions, such as lyophilization, washing, and laser irradiation, whereas chemosynthetic SeNPs transformed into a trigonal structure in the same conditions. Additionally, a core-shell structure was observed in biogenic SeNPs after electron beam irradiation. Further analysis revealed that biogenic SeNPs showed a coordination reaction between Se atoms and surface binding biomacromolecules, indicating that the outer layer of Se-biomacromolecules complex prevented the SeNPs from crystallizing. We also investigated the effects of SeNPs crystal structures on the bioavailability in bacteria, yeast, and plants, finding that the amorphous structure of SeNPs determined Se bioavailability.

Impact of Sodium-Glucose Cotransporter 2 Inhibitor on Recurrence After Catheter Ablation for Atrial Fibrillation in Patients With Diabetes: A Propensity-Score Matching Study and Meta-Analysis.

BACKGROUND: The association between sodium-glucose cotransporter 2 inhibitors (SGLT2i) and atrial fibrillation (AF) recurrence after catheter ablation among patients with diabetes and AF remains unclear. METHODS AND RESULTS: Patients with AF undergoing initial catheter ablation with a history of diabetes from the China AF registry were included. Patients using SGLT2i were identified and matched by propensity score with non-SGLT2i patients in a 1:3 ratio. The main outcome was AF recurrence during the 18-month follow-up. A total of 138 patients with diabetes with SGLT2i therapy and 387 without SGLT2i were analyzed. AF recurrence occurred in 37 patients (26.8%) in the SGLT2i group and 152 patients (39.3%) in the non-SGLT2i group during a total of 593.3 person-years follow-up. The SGLT2i group was associated with lower AF recurrence compared with the non-SGLT2i group (hazard ratio, 0.63 [95% CI, 0.44-0.90], P=0.007). A total of 4 studies were analyzed in our meta-analysis demonstrating that SGLT2i was associated with lower AF recurrence after catheter ablation (odds ratio, 0.61 [95% CI, 0.54-0.69]; P<0.001, I2=0.0%). CONCLUSIONS: Our prospective study coupled with a meta-analysis demonstrated a lower risk of AF recurrence with the use of SGLT2i among patients with diabetes after AF ablation.

Catheter ablation versus medical therapy for atrial fibrillation with prior stroke history: a prospective propensity score-matched cohort study.

BACKGROUND: Patients with atrial fibrillation (AF) and prior stroke history have a high risk of cardiovascular events despite anticoagulation therapy. It is unclear whether catheter ablation (CA) has further benefits in these patients. METHODS: AF patients with a previous history of stroke or systemic embolism (SE) from the prospective Chinese Atrial Fibrillation Registry study between August 2011 and December 2020 were included in the analysis. Patients were matched in a 1:1 ratio to CA or medical treatment (MT) based on propensity score. The primary outcome was a composite of all-cause death or ischemic stroke (IS)/SE. RESULTS: During a total of 4.1 ± 2.3 years of follow-up, the primary outcome occurred in 111 patients in the CA group (3.3 per 100 person-years) and in 229 patients in the MT group (5.7 per 100 person-years). The CA group had a lower risk of the primary outcome compared to the MT group [hazard ratio (HR) = 0.59, 95% CI: 0.47-0.74, P < 0.001]. There was a significant decreasing risk of all-cause mortality (HR = 0.43, 95% CI: 0.31-0.61, P < 0.001), IS/SE (HR = 0.73, 95% CI: 0.54-0.97, P = 0.033), cardiovascular mortality (HR = 0.32, 95% CI: 0.19-0.54, P < 0.001) and AF recurrence (HR = 0.33, 95% CI: 0.30-0.37, P < 0.001) in the CA group compared to that in the MT group. Sensitivity analysis generated consistent results when adjusting for time-dependent usage of anticoagulants. CONCLUSIONS: In AF patients with a prior stroke history, CA was associated with a lower combined risk of all-cause death or IS/SE. Further clinical trials are warranted to confirm the benefits of CA in these patients.

Apoptosis and oxidative stress of mouse breast carcinoma 4T1 and human intestinal epithelial Caco-2 cell lines caused by the phycotoxin gymnodimine-A.

Gymnodimine-A (GYM-A) is a cyclic imine phycotoxin produced by some marine dinoflagellates. It can cause rapid death of mice via intraperitoneal administration and frequently accumulate in shellfish potentially threatening human health. In this study, four different cell lines were exposed to GYM-A for the viability assessment. Results showed that GYM-A was cytotoxic with concentration-dependent pattern to each cell type, with mean IC50 values ranging from 1.39 to 2.79 µmol L-1. Results suggested that the loss of cell viability of 4T1 and Caco-2 cells was attributed to apoptosis. Furthermore, the collapse of mitochondrial membrane potential and caspases activation were observed in the GYM-A-treated cells. Reactive oxygen species (ROS) and lipid peroxides (LPO) levels were markedly increased in 4T1 and Caco-2 cells exposed to GYM-A at 2 µmol L-1, and the oxidative stress in 4T1 cells was more obvious than that in Caco-2 cells. Additionally, unusual ultrastructure impairment on mitochondria and mitophagosomes occurred in the GYM-A-treated cells. These results suggested that an ROS-mediated mitochondrial pathway for apoptosis and mitophagy was implicated in the cytotoxic effects induced by GYM-A. This is the first report to explore the cytotoxic mechanisms of GYM-A through apoptosis and oxidative stress, and it will provide theoretical foundations for the potential therapeutic applications of GYM-A.

Atrial fibrillation catheter ablation associated silent cerebral emboli: A narrative review.

The incidence of silent cerebral emboli (SCE) associated with atrial fibrillation catheter ablation (AFCA) is much higher than that of stroke/transient ischemic attack (TIA). Interventional electrophysiologists have been increasingly alerted to asymptomatic cerebral infarction over the years. Plentiful studies revealed that diagnostic definitions, detection modalities, energy sources, ablation strategies, perioperative anticoagulation regimens, and patient-related factors were associated with the risk of AFCA-associated SCE. Studies related to non-interventional procedures found that SCE may prompt stroke, cognitive decline, and dementia later in life, suggesting a possible role of AFCA-associated SCE in the cognitive function of patients with AF. However, there is no consistent evidence for this view to date. Given that the majority of patients with AF being elderly and the increased risk of cognitive impairment in AF itself, efforts should be made to minimize the occurrence of AFCA-associated SCE.

Synchronous decomplexation and mineralization of copper complexes by activating peroxymonosulfate with magnetic bimetallic biochar derived from municipal sludge.

Efficient removal of copper complexes is a challenging issue due to their robust stability and solubility. In this study, CoFe2O4-Co0 loaded sludge-derived biochar (MSBC), a magnetic heterogeneous catalyst, was prepared to activate peroxymonosulfate (PMS) for the decomplexation and mineralization of some typical copper complexes (including Cu(Ⅱ)-EDTA, Cu(Ⅱ)-NTA, Cu(Ⅱ)-citrate, and Cu(Ⅱ)-tartrate). The results showed that abundant cobalt ferrite and cobalt nanoparticles were decorated in the plate-like carbonaceous matrix, making it a higher degree of graphitization, better conductivity and more excellent catalytic activity than the raw biochar. Cu(Ⅱ)-EDTA was chosen as the representative copper complex. Under the optimum condition, the decomplexation and mineralization efficiency of Cu(Ⅱ)-EDTA in MSBC/PMS system were 98% and 68% within 20 min, respectively. The mechanistic investigation confirmed that the activation of PMS by MSBC followed both a radical pathway contributed by SO4•- and •OH and a nonradical pathway contributed by 1O2. In addition, the electron transfer pathway between Cu(Ⅱ)-EDTA and PMS facilitated the decomplexation of Cu(Ⅱ)-EDTA. Jointly, CO, Co0, and the redox cycles of Co(Ⅲ)/Co(Ⅱ) and Fe (Ⅲ)/Fe (Ⅱ) were found to play a critical role in the decomplexation process. Overall, the MSBC/PMS system provides a new strategy for efficient decomplexation and mineralization of copper complexes.

Effects of Mn content on austenite stability and mechanical properties of low Ni alumina-forming austenitic heat-resistant steel: a first-principles study.

Low Ni alumina-forming austenitic (AFA) heat-resistant steel is an advanced high-temperature stainless steel with reduced cost, good machinability, high-temperature creep strength, and high-temperature corrosion resistance. Using the First-principles approach, this study examined the effect of Mn content on austenite stability and mechanical properties at the atomic level. Adding Mn to low Ni-AFA steel increases the unit cell volume with an accompanying increase in the absolute value of formation energy; the austenite formed more easily. The austenitic matrix binding energy decreases and remains negative, indicating austenite stability. As the Mn content increases from 3.2 to 12.8 wt%, the system's bulk modulus (B) rises significantly, and the shear modulus (G) falls. In addition, the system's strength and hardness decrease, and the Poisson ratio of the austenite matrix increases with improved elasticity; the system has excellent plasticity with an increase in the B/G. For the Fe22-Cr5-Ni3-Al2 system, with the increase of Mn content, the electron density distribution between the atoms is relatively uniform, and the electrons around the Mn atoms are slightly sparse, which will slightly reduce the structural stability of the matrix. The experiment demonstrated the matrix maintains the austenitic structure when adding 3.2-12.8 wt% Mn elements to low Ni-AFA steel. At an Mn content of 8 wt%, the overall mechanical properties of the high-Mn AFA steel are optimal, with a tensile strength of 581.64 MPa, a hardness of 186.17 HV, and an elongation of 39%.

Selected ssDNA aptamers-graphene oxide-based fluorescent biosensor to detect sulfameter in milk.

The abuse of sulfameter (SME) in animal husbandry can cause drug resistance and toxic or allergic reactions in humans. Therefore, it is very important to establish a simple, inexpensive, and efficient method for detecting SME in food. In this work, we propose a single fluorescent aptamer/graphene oxide (GO)-based biosensor to detect SME residues in milk. Aptamers that specifically bind to SME were screened using capture-SELEX and a ssDNA library immobilized on magnetic beads. The 68 active candidate aptamers were chemically synthesized for specificity and affinity characterization. Among the aptamers, the aptamer sulf-1 revealed the highest affinity (Kd = 77 ± 15 nM) to SME and was selected to construct a GO-based fluorescent biosensor for real milk sample detection. Under optimal conditions, the single fluorescent aptasensor had a wide linear range (R2 was 0.997) from 7 to 336 ng/ml and a low detection limit of 3.35 ng/ml that was calculated with a 3SD/slope. The single fluorescent method was also validated using SME-fortified milk samples, showing average recoveries ranging from 99.01% to 104.60% with a relative standard deviation of less than 3.88%. These results demonstrate that this novel aptamer sensor provides an opportunity for sensitive, convenient, and accurate detection of SME residues in milk.

High glucose-induced glucagon resistance and membrane distribution of GCGR revealed by super-resolution imaging.

The glucagon receptor (GCGR) is a member of the class B G protein-coupled receptor family. Many research works have been carried out on GCGR structure, glucagon signaling pathway, and GCGR antagonists. However, the expression and fine distribution of GCGR proteins in response to glucagon under high glucose remain unclear. Using direct stochastic optical reconstruction microscopy (dSTORM) imaging, nanoscale GCGR clusters were observed on HepG2 cell membranes, and high glucose promoted GCGR expression and the formation of more and larger clusters. Moreover, glucagon stimulation under high glucose did not inhibit GCGR levels as significantly as that under low glucose and did not increase the downstream cyclic 3,5'-adenosine monophosphate-protein kinase A (cAMP-PKA) signal, and there were still large-size clusters on the membranes, indicating that high glucose induced glucagon resistance. In addition, high glucose induced stronger glucagon resistance in hepatoma cells compared with hepatic cells. Our work will pave a way to further our understanding of the pathogenesis of diabetes and develop more effective drugs targeting GCGR.

Discovery of pentacyclic triterpenoid glycosides with anti-proliferative activities from Ardisialindleyana.

One new pentacyclic triterpenoid glycoside, ardisiapunine E (1), along with two known compounds were isolated from the root of Ardisia lindleyana D.Dietr. Their structures were elucidated by 1H and 13C NMR, DEPT, HMBC, HSQC, 1H-1H COSY and NOESY spectroscopic analyses, ESI-MS, and literature. Compounds 1-3 exhibited obvious anti-proliferative activities against the HeLa cell line in a dose- and time-dependent manner by inducing G2/M phase arrest and apoptosis in vitro, both consisting of pentacyclic triterpenes and sugar. Hence, this study identified a new and two known pentacyclic triterpenoid glycosides promoting apoptosis as a potential anti-proliferative agent.