Concise synthesis of 3-C-glycosyl isocoumarins and 2-glycosyl-4H-chromen-4-ones.

A new Ru-catalyzed C-H activation/cyclization reaction for the synthesis of 3-C-glycosyl isocoumarins and 2-glycosyl-4H-chromen-4-ones with carbonyl sulfoxonium ylide glycogen are reported. In this catalytic system, benzoic acid and its derivatives react with carbonyl sulfoxonium ylide glycogen to yield isocoumarin C-glycosides, while 2-hydroxybenzaldehyde substrates react to produce chromone C-glycosides. These reactions were characterized by mild reaction conditions, broad substrate scope, high functional-group compatibility, and high stereoselectivity to yield several high-value isocoumarins and chromone skeleton-containing C-glycosides. The methods were successfully implemented in the context of large-scale reactions and the late-stage modification of complex natural products.

Intermittent Fasting Targets Osteocyte Neuropeptide Y to Relieve Osteoarthritis.

Osteoarthritis is a highly prevalent progressive joint disease that still requires an optimal therapeutic approach. Intermittent fasting is an attractive dieting strategy for improving health. Here this study shows that intermittent fasting potently relieves medial meniscus (DMM)- or natural aging-induced osteoarthritic phenotypes. Osteocytes, the most abundant bone cells, secrete excess neuropeptide Y (NPY) during osteoarthritis, and this alteration can be altered by intermittent fasting. Both NPY and the NPY-abundant culture medium of osteocytes (OCY-CM) from osteoarthritic mice possess pro-inflammatory, pro-osteoclastic, and pro-neurite outgrowth effects, while OCY-CM from the intermittent fasting-treated osteoarthritic mice fails to induce significant stimulatory effects on inflammation, osteoclast formation, and neurite outgrowth. Depletion of osteocyte NPY significantly attenuates DMM-induced osteoarthritis and abolishes the benefits of intermittent fasting on osteoarthritis. This study suggests that osteocyte NPY is a key contributing factor in the pathogenesis of osteoarthritis and intermittent fasting represents a promising nonpharmacological antiosteoarthritis method by targeting osteocyte NPY.

Assembly of Heterocyclic C-Glycosides by Ru-Catalyzed C-H Activation/Cyclization with Carbonyl Sulfoxonium Ylide Glyco-Reagents.

New carbonyl sulfoxonium ylide glyco-reagents have been developed, enabling the synthesis of versatile heteroarene C-glycosides through a Ru-catalyzed C-H activation/annulation strategy. These reactions tolerate various saccharide donors and represent a significant advance in the stereoselective synthesis of heterocyclic C-glycosides. Furthermore, the strategy and methods could be applied to large-scale reactions and late-stage modifications of some structurally complex natural products or drugs.

Calixarene-Based Supramolecular Sensor Array for Pesticide Discrimination.

The identification and detection of pesticides is crucial to protecting both the environment and human health. However, it can be challenging to conveniently and rapidly differentiate between different types of pesticides. We developed a supramolecular fluorescent sensor array, in which calixarenes with broad-spectrum encapsulation capacity served as recognition receptors. The sensor array exhibits distinct fluorescence change patterns for seven tested pesticides, encompassing herbicides, insecticides, and fungicides. With a reaction time of just three minutes, the sensor array proves to be a rapid and efficient tool for the discrimination of pesticides. Furthermore, this supramolecular sensing approach can be easily extended to enable real-time and on-site visual detection of varying concentrations of imazalil using a smartphone with a color scanning application. This work not only provides a simple and effective method for pesticide identification and quantification, but also offers a versatile and advantageous platform for the recognition of other analytes in relevant fields.

Supramolecular 3 in 1: A Lubrication and Co-Delivery System for Synergistic Advanced Osteoarthritis Therapy.

The complexity, heterogeneity, and drug resistance of diseases necessitate a shift in therapeutic paradigms from monotherapy to combination therapy, which could augment treatment efficiency. Effective treatment of advanced osteoarthritis (OA) requires addressing three key factors contributing to its deterioration: chronic joint inflammation, lubrication dysfunction, and cartilage-tissue degradation. Herein, we present a supramolecular nanomedicine of multifunctionality via molecular recognition and self-assembly. The employed macrocyclic carrier, zwitterion-modified cavitand (CV-2), not only accurately loads various drugs but also functions as a therapeutic agent with lubricating properties for the treatment of OA. Kartogenin (KGN), a drug for articular cartilage regeneration and protection, and flurbiprofen (FP), an anti-inflammatory agent, were coloaded onto CV-2 assembly, forming a supramolecular nanomedicine KGN&FP@CV-2. The three-in-one combination therapy of KGN&FP@CV-2 addresses the three pathological features for treating OA collectively, and thus provides long-term therapeutic benefits for OA through sustained drug release and intrinsic lubrication in vivo. The multifunctional integration of macrocyclic delivery and therapeutics provides a simple, flexible, and universal platform for the synergistic treatment of diseases involving multiple drugs.

Single Molecular Nanomedicines Based on Macrocyclic Carrier-Drug Conjugates for Concentration-Independent Encapsulation and Precise Activation of Drugs.

Nanomedicines often rely on noncovalent self-assembly and encapsulation for drug loading and delivery. However, challenges such as reproducibility issues due to the multicomponent nature, off-target activation caused by premature drug release, and complex pharmacokinetics arising from assembly dissociation have hindered their clinical translation. In this study, we introduce an innovative design concept termed single molecular nanomedicine (SMNM) based on macrocyclic carrier-drug conjugates. Through the covalent linkage of two chemotherapy drugs to a hypoxia-cleavable macrocyclic carrier, azocalix[4]arene, we obtained two self-included complexes to serve as SMNMs. The intramolecular inclusion feature of the SMNMs has not only demonstrated comprehensive shielding and protection for the drugs but also effectively prevented off-target drug leakage, thereby significantly reducing their side effects and enhancing their antitumor therapeutic efficacy. Additionally, the attributes of being a single component and molecularly dispersed confer advantages such as ease of preparation and good reproducibility for SMNMs, which is desirable for clinical applications.

Risk Factors Asscociated with Hypokalemia during Postanesthesia Recovery and Its Impact on Outcomes in Gynecological Patients: A Propensity Score Matching Study.

OBJECTIVE: This study aimed to explore the risk factors and outcomes of hypokalemia during the recovery period from anesthesia in the gynecological population. METHODS: This retrospective cohort study included 208 patients who underwent gynecological surgery at our institution between January 2021 and March 2022. Data were collected for each patient, including demographics, disease status, surgical data, and clinical information. Preoperative bowel preparation, postoperative gastrointestinal function, and electrolyte levels were compared between the two groups using propensity score matching (PSM). RESULTS: The incidence of hypokalemia (serum potassium level <3.5 mmol/L) during the recovery period from anesthesia was approximately 43.75%. After PSM, oral laxative use (96.4% vs. 82.4%, P=0.005), the number of general enemas (P=0.014), and the rate of ≥2 general enemas (92.9% vs. 77.8%, P=0.004) were identified as risk factors for hypokalemia, which was accompanied by decreased PaCO2 and hypocalcemia. There were no significant differences in postoperative gastrointestinal outcomes, such as the time to first flatus or feces, the I-FEED score (a scoring system was created to evaluate impaired postoperative gastrointestinal function), or postoperative recovery outcomes, between the hypokalemia group and the normal serum potassium group. CONCLUSION: Hypokalemia during postanesthesia recovery period occurred in 43.75% of gynecological patients, which resulted from preoperative mechanical bowel preparation; however, it did not directly affect clinical outcomes, including postoperative gastrointestinal function, postoperative complications, and length of hospital stay.

Active targeting tumor therapy using host-guest drug delivery system based on biotin functionalized azocalix[4]arene.

Host-guest drug delivery systems (HGDDSs) provided a facile method for incorporating biomedical functions, including efficient drug-loading, passive targeting, and controlled drug release. However, developing HGDDSs with active targeting is hindered by the difficult functionalization of popular macrocycles. Herein, we report an active targeting HGDDS based on biotin-modified sulfonated azocalix[4]arene (Biotin-SAC4A) to efficiently deliver drug into cancer cells for improving anti-tumor effect. Biotin-SAC4A was synthesized by amide condensation and azo coupling. Biotin-SAC4A demonstrated hypoxia responsive targeting and active targeting through azo and biotin groups, respectively. DOX@Biotin-SAC4A, which was prepared by loading doxorubicin (DOX) in Biotin-SAC4A, was evaluated for tumor targeting and therapy in vitro and in vivo. DOX@Biotin-SAC4A formulation effectively killed cancer cells in vitro and more efficiently delivered DOX to the lesion than the similar formulation without active targeting. Therefore, DOX@Biotin-SAC4A significantly improved the in vivo anti-tumor effect of free DOX. The facilely prepared Biotin-SAC4A offers strong DOX complexation, active targeting, and hypoxia-triggered release, providing a favorable host for effective breast cancer chemotherapy in HGDDSs. Moreover, Biotin-SAC4A also has potential to deliver agents for other therapeutic modalities and diseases.

The association of post-embryo transfer SARS-CoV-2 infection with early pregnancy outcomes in in vitro fertilization: a prospective cohort study.

BACKGROUND: The influence of SARS-CoV-2 infection after embryo transfer on early pregnancy outcomes in in vitro fertilization or intracytoplasmic sperm injection-embryo transfer treatment remains inadequately understood. This knowledge gap endures despite an abundance of studies investigating the repercussions of preceding SARS-CoV-2 infection on early pregnancy outcomes in spontaneous pregnancies. OBJECTIVE: This study aimed to investigate the association between SARS-CoV-2 infection within 10 weeks after embryo transfer and early pregnancy outcomes in patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment. STUDY DESIGN: This prospective cohort study was conducted at a single public in vitro fertilization center in China. Female patients aged 20 to 39 years, with a body mass index ranging from 18 to 30 kg/m2, undergoing in vitro fertilization/intracytoplasmic sperm injection treatment, were enrolled between September 2022 and December 2022, with follow-up extended until March 2023. The study tracked SARS-CoV-2 infection time (≤14 days, ≤28 days, and ≤10 weeks after embryo transfer), symptoms, vaccination status, the interval between vaccination and embryo transfer, and early pregnancy outcomes, encompassing biochemical pregnancy rate, implantation rate, clinical pregnancy rate, and early miscarriage rate. The study used single-factor analysis and multivariate logistic regression to examine the association between SARS-CoV-2 infection status, along with other relevant factors, and the early pregnancy outcomes. RESULTS: A total of 857 female patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment were analyzed. In the first stage, SARS-CoV-2 infection within 14 days after embryo transfer did not have a significant negative association with the biochemical pregnancy rate (adjusted odds ratio, 0.74; 95% confidence interval, 0.51-1.09). In the second stage, SARS-CoV-2 infection within 28 days after embryo transfer had no significant association with the implantation rate (36.6% in infected vs 44.0% in uninfected group; P=.181). No statistically significant association was found with the clinical pregnancy rate after adjusting for confounding factors (adjusted odds ratio, 0.69; 95% confidence interval, 0.56-1.09). In the third stage, SARS-CoV-2 infection within 10 weeks after embryo transfer had no significant association with the early miscarriage rate (adjusted odds ratio, 0.77; 95% confidence interval, 0.35-1.71). CONCLUSION: Our study suggests that SARS-CoV-2 infection within 10 weeks after embryo transfer may not be negatively associated with the biochemical pregnancy rate, implantation rate, clinical pregnancy rate, and early miscarriage rate in patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment. It is important to note that these findings are specific to the target population of in vitro fertilization/intracytoplasmic sperm injection patients aged 20 to 39 years, without previous SARS-CoV-2 infection, and with a body mass index of 18 to 30 kg/m2. This information offers valuable insights, addressing current concerns and providing a clearer understanding of the actual risk associated with SARS-CoV-2 infection after embryo transfer.

Guest adaptative supramolecular sensing strategy for warning the risky aflatoxins in contaminated cereals.

In the face of diversified analytes, it is a great challenge and infeasible task to design and synthesize corresponding macrocyclic hosts to realize the ideal supramolecular sensing. Herein, we proposed a novel supramolecular sensing strategy, guest adaptative assay (GAA), in which analyte was quantitatively transformed under mild conditions to perfectly adapt to macrocyclic host. As a health-threatening "landmine" in cereals, aflatoxins were converted by the aid of alkali hydrolysis to satisfactorily obtain aflatoxins transformants in ionic state, resulting in sensitive response by the guanidinocalix[5]arene•fluorescein reporter pair. Surprisingly, the established strategy not only exhibited effective practicality in screening out high-risk cereals contaminated with aflatoxins, but also relieved the laborious task of macrocycle design and screening in supramolecular sensing.

Supramolecular Integration of Multifunctional Nanomaterial by Mannose-Decorated Azocalixarene with Ginsenoside Rb1 for Synergistic Therapy of Rheumatoid Arthritis.

The complexity and progressive nature of diseases require the exploitation of multifunctional materials. However, introducing a function inevitably increases the complexity of materials, which complicates preparation and decreases reproducibility. Herein, we report a supramolecular integration of multifunctional nanomaterials based on mannose-modified azocalix[4]arene (ManAC4A) and ginsenoside Rb1 (Rb1), which showed advances of simplicity and reproducibility. ManAC4A possesses reactive oxygen species (ROS) scavenging capacity and hypoxia-responsiveness, together with macrophage-targeting and induction functionality. Collectively, the Rb1@ManAC4A assembly simply prepared by two components is integrated with multifunction, including triple targeting (ELVIS targeting, macrophage-targeting, and hypoxia-targeted release) and triple therapy (ROS scavenging, macrophage polarization, and the anti-inflammatory effect of Rb1). The spontaneous assembly and recognition of ManAC4A, with its precise structure and molecular weight, facilitated the simple and straightforward preparation of Rb1@ManAC4A, leading to excellent batch consistency. Progress in simplicity and reproducibility, as directed by this research, will catalyze the clinical translation of multifunctional materials.

Aptamer-functionalized hydrogels promote bone healing by selectively recruiting endogenous bone marrow mesenchymal stem cells.

Bone regeneration heavily relies on bone marrow mesenchymal stem cells (BMSCs). However, recruiting endogenous BMSCs for in situ bone regeneration remains challenging. In this study, we developed a novel BMSC-aptamer (BMSC-apt) functionalized hydrogel (BMSC-aptgel) and evaluated its functions in recruiting BMSCs and promoting bone regeneration. The functional hydrogels were synthesized between maleimide-terminated 4-arm polyethylene glycols (PEG) and thiol-flanked PEG crosslinker, allowing rapid in situ gel formation. The aldehyde group-modified BMSC-apt was covalently bonded to a thiol-flanked PEG crosslinker to produce high-density aptamer coverage on the hydrogel surface. In vitro and in vivo studies demonstrated that the BMSC-aptgel significantly increased BMSC recruitment, migration, osteogenic differentiation, and biocompatibility. In vivo fluorescence tomography imaging demonstrated that functionalized hydrogels effectively recruited DiR-labeled BMSCs at the fracture site. Consequently, a mouse femur fracture model significantly enhanced new bone formation and mineralization. The aggregated BMSCs stimulated bone regeneration by balancing osteogenic and osteoclastic activities and reduced the local inflammatory response via paracrine effects. This study's findings suggest that the BMSC-aptgel can be a promising and effective strategy for promoting in situ bone regeneration.

Dynamic chromatin accessibility tuning by the long noncoding RNA ELDR accelerates chondrocyte senescence and osteoarthritis.

Epigenetic reprogramming plays a critical role in chondrocyte senescence during osteoarthritis (OA) pathology, but the underlying molecular mechanisms remain to be elucidated. Here, using large-scale individual datasets and genetically engineered (Col2a1-CreERT2;Eldrflox/flox and Col2a1-CreERT2;ROSA26-LSL-Eldr+/+ knockin) mouse models, we show that a novel transcript of long noncoding RNA ELDR is essential for the development of chondrocyte senescence. ELDR is highly expressed in chondrocytes and cartilage tissues of OA. Mechanistically, exon 4 of ELDR physically mediates a complex consisting of hnRNPL and KAT6A to regulate histone modifications of the promoter region of IHH, thereby activating hedgehog signaling and promoting chondrocyte senescence. Therapeutically, GapmeR-mediated silencing of ELDR in the OA model substantially attenuates chondrocyte senescence and cartilage degradation. Clinically, ELDR knockdown in cartilage explants from OA-affected individuals decreased the expression of senescence markers and catabolic mediators. Taken together, these findings uncover an lncRNA-dependent epigenetic driver in chondrocyte senescence, highlighting that ELDR could be a promising therapeutic avenue for OA.

Triple targeting host-guest drug delivery system based on lactose-modified azocalix[4]arene for tumor ablation.

Host-guest drug delivery systems (HGDDSs) have been studied in an effort to modify the characteristics of therapeutic agents through noncovalent interactions, reduce toxic side effects and improve therapeutic effects. However, it is still an important task to continuously improve the targeting ability of HGDDSs, which is conducive to the development of precision medicine. Herein, we utilize the lactose-modified azocalix[4]arene (LacAC4A) as a triple targeting drug carrier customized for antitumor purposes. LacAC4A integrates three targeting features, passive targeting through the enhancing permeability and retention effect, active targeting by the interactions of lactose and the asialoglycoprotein receptors on the surface of tumor cells, and stimuli-responsive targeting via the reduction of the azo group under a hypoxia microenvironment. After loading doxorubicin (DOX) in LacAC4A, the supramolecular nanoformulation DOX@LacAC4A clearly showed the effective suppression of tumor growth through in vivo experiments. LacAC4A can achieve effective targeting, rapid release, and improve drug bioavailability. This design principle will provide a new material for drug delivery systems.

An Antitumor Dual-Responsive Host-Guest Supramolecular Polymer Based on Hypoxia-Cleavable Azocalix[4]arene.

The exploitation of specific guests which can respond to external stimuli is the main approach for the construction of stimuli-responsive supramolecular polymers (SPs) based on host-guest interactions. Most functional guests, however, fail to manifest stimuli-responses. Herein, a hypoxia-responsive dimeric azocalixarene (D-SAC4A) with outstanding hosting properties was used as the macrocyclic building block for the preparation of host stimuli-responsive SPs. Since azocalixarenes can also be compatible with stimuli-responsive guests, an antitumor drug, camptothecin (CPT), was chosen and linked via a disulfide-containing linker to afford a glutathione (GSH)-responsive ditropic guest (D-CPT). A unique dual-responsive SP was obtained by 1 : 1 mixing of D-SAC4A and D-CPT in water, which further assembled into SP nanoparticles (DSPNs). DSPNs displayed outstanding stability against dilution and biological interferants, as well as precise CPT-release under GSH and hypoxia conditions. In vitro and in vivo experiments demonstrated the good biosafety and tumor-suppressive effects of DSPNs.

A heteromultivalent host-guest sensor array for cell recognition and discrimination.

We present a supramolecular sensor array based on a series of heteromultivalent macrocyclic coassemblies using amphiphilic calixarenes and cyclodextrin as the building blocks for cell recognition. The corresponding cross-reactivity between the coassemblies and cells served as the unique fingerprint for cell classification, and successfully identified the normal cell lines, cancerous cell lines, and cross-contaminated cells.

Structural Elucidation and Total Synthesis for the Pair of Unprecedented Polypyridines with Anti-AChE and HIV-1 Protease Activities from Alangium chinense.

Unlike reported pyridine hybrids, 2S (1a) and 2R-alanginenmine A (1b) from Alangium chinense featuring an unprecedented piperidine-bridged polypyridine skeleton represented a pair of alkaloid subtypes with a unique multiple pyridine scaffold. Enlightened by the rare structural characteristics and possible biosynthetic pathway, (±)-alanginenmine A (1) have been achieved in ideal yield by gram-class total synthesis with four steps. In addition, both compounds 1a and 1b exhibited anti-acetylcholinesterase (AChE) and HIV-1 protease activities in the biological activity evaluation. Further, molecular docking was investigated for the mechanism of action between the isolated compounds and HIV-1 protease. The stronger Coulomb interactions and van der Waals interaction, as well as the hydrogen bond interactions of 1a, might be the main cause for its better anti-HIV-1 protease activity than 1b. This work provided a comprehensive research including natural product discovery, bioactivity evaluation, and total synthesis for the new type of leading anti-HIV-1 protease.

Lactose azocalixarene drug delivery system for the treatment of multidrug-resistant pseudomonas aeruginosa infected diabetic ulcer.

Diabetic wound is one of the most intractable chronic wounds that is prone to bacterial infection. Hypoxia is an important feature in its microenvironment. However, it is challenging for antimicrobial therapy to directly apply the existing hypoxia-responsive drug delivery systems due to the active targeting deficiency and the biofilm obstacle. Herein, we customizes a hypoxia-responsive carrier, lactose-modified azocalix[4]arene (LacAC4A) with the ability to actively target and inhibit biofilm. By loading ciprofloxacin (Cip), the resultant supramolecular nanoformulation Cip@LacAC4A demonstrates enhanced antibacterial efficacy resulting from both the increased drug accumulation and the controlled release at the site of infection. When applied on diabetic wounds together with multidrug-resistant Pseudomonas aeruginosa infection in vivo, Cip@LacAC4A induces definitely less inflammatory infiltration than free Cip, which translates into high wound healing performance. Importantly, such design principle provides a direction for developing antimicrobial drug delivery systems.

A facile way to construct sensor array library via supramolecular chemistry for discriminating complex systems.

Differential sensing, which discriminates analytes via pattern recognition by sensor arrays, plays an important role in our understanding of many chemical and biological systems. However, it remains challenging to develop new methods to build a sensor unit library without incurring a high workload of synthesis. Herein, we propose a supramolecular approach to construct a sensor unit library by taking full advantage of recognition and assembly. Ten sensor arrays are developed by replacing the building block combinations, adjusting the ratio between system components, and changing the environment. Using proteins as model analytes, we examine the discriminative abilities of these supramolecular sensor arrays. Then the practical applicability for discriminating complex analytes is further demonstrated using honey as an example. This sensor array construction strategy is simple, tunable, and capable of developing many sensor units with as few syntheses as possible.

Drug in Drug: A Host-Guest Formulation of Azocalixarene with Hydroxychloroquine for Synergistic Anti-Inflammation.

Macrocyclic delivery and therapeutics are two significant topics in supramolecular biomedicine. The functional integration of these topics would open new avenues for treating diseases synergistically. However, these two individual topics have only been occasionally merged, probably because of the lack of functionalized design of macrocyclic host and the lack of efficient recognition between host and guest drugs. Herein, a "drug-in-drug" strategy is proposed, in which an active drug is encapsulated by a macrocycle possessing therapeutic activity to form a multifunctional supramolecular active pharmaceutical ingredient. As a proof-of-concept, a complex of hydroxychloroquine (HCQ) with sulfonated azocalix[4]arene (HCQ@SAC4A) is prepared to treat rheumatoid arthritis (RA) in a combined fashion. SAC4A is a therapeutic agent that exhibits scavenging capacity for reactive oxygen species and exerts an anti-inflammatory effect. It is also a hypoxia-responsive carrier that can deliver HCQ directly to the inflammatory articular cavity. Consequently, HCQ@SAC4A achieves the synergistic anti-inflammatory effect on both inflamed RAW 264.7 cells and RA rats. This effect is attributed to the temporal and spatial consistency of the two active ingredients of the complex. As a new paradigm for combinational therapy, the drug-in-drug strategy advances in easy preparation, mix-and-match combination, and precise ratiometric control.