From Hit to Lead: Structure-Based Optimization of Novel Selective Inhibitors of Receptor-Interacting Protein Kinase 1 (RIPK1) for the Treatment of Inflammatory Diseases.

Receptor-interacting protein kinase 1 (RIPK1) is a key regulator of cellular necroptosis, which is considered as an important therapeutic target for necroptosis-related indications. Herein, we report the structural optimization and structure-activity relationship investigations of a series of eutectic 5-substituted-indole-3-carboxamide derivatives. The prioritized compound 10b exhibited low nanomolar IC50 values against RIPK1 and showed good kinase selectivity. Based on its eutectic structure, 10b occupied both the allosteric and ATP binding pockets of RIPK1, making it a potent dual-mode inhibitor of RIPK1. In vitro, 10b had a potent protective effect against necroptosis in cells. Compound 10b also provided robust protection in a TNFα-induced systemic inflammatory response syndrome (SIRS) model and imiquimod (IMQ)-induced psoriasis model. It also showed good pharmacokinetic properties and low toxicity. Overall, 10b is a promising lead compound for drug discovery targeting RIPK1 and warrants further study.

Risk Factors and a Nomogram Model for Residual Symptoms of Cured Benign Paroxysmal Positional Vertigo.

BACKGROUND: We aimed to analyze the independent risk factors that affect the treatment outcomes of residual symptoms of cured benign paroxysmal positional vertigoand to construct a nomogram model. METHODS: A total of 186 benign paroxysmal positional vertigo patients who were treated in our hospital from June 2019 to August 2021 were selected. According to whether there were residual symptoms, they were divided into a group with residual symptoms (n=82) and a group without residual symptoms (n = 104). The logistic regression model was used to analyze the independent risk factors affecting the treatment outcomes, and the results were incorporated into R software to establish a nomogram model for verification. RESULTS: The incidence rate of residual symptoms in the 186 patients was 44.09% (82/186). Logistic regression analysis showed that age, course of disease, number of maneuvers, anxiety state, diabetes mellitus, and hypertension were independent risk factors affecting the treatment outcomes of residual symptoms after cured benign paroxysmal positional vertigo. The area under the receiver operating characteristic curve of the nomogram model was 0.938. The calibration curve was fitted well (χ2 = 8.165, P = .417). CONCLUSION: The nomogram model constructed based on age, course of disease, number of maneuvers, anxiety state, diabetes mellitus, and hypertension had a high predictive value for the treatment outcomes of residual symptoms in benign paroxysmal positional vertigo patients.

Discovery of benzodiazepine derivatives as a new class of covalent inhibitors of SARS-CoV-2 main protease.

The COVID-19 pandemic has caused people immense suffering all over the world. Although the World Health Organization (WHO) has announced the end of the pandemic, the sporadic virus epidemic is still ongoing and may exist permanently. Effective antivirals against SARS-CoV-2 are important to deal with the long-term threat. The main protease (Mpro) is a crucial target for drug development due to its role in the process of virus's replication and transcription. Herein, we report benzodiazepine derivatives as a new class of Mpro inhibitors. Structure-activity relationship (SAR) studies led to the discovery of the most active compound, methyl 10-(2-chloroacetyl)-1-oxo-11-(4-(trifluoromethyl)phenyl)-2,3,4,5,10,11-hexahydro-1H-dibenzo[b,e][1,4]-diazepine-7-carboxylate (11a), which shows an IC50 value of 0.180 ± 0.004 µM. The X-ray crystal structure shows that 11a covalently binds to Mpro. Collectively, we have obtained a new small molecule inhibitor targeting Mpro, which can serve as a lead compound for subsequent drug discovery against SARS-CoV-2.

Discovery and structure-activity relationship studies of novel α-ketoamide derivatives targeting the SARS-CoV-2 main protease.

The SARS-CoV-2 main protease (Mpro, also named 3CLpro) is a promising antiviral target against COVID-19 due to its functional importance in viral replication and transcription. Herein, we report the discovery of a series of α-ketoamide derivatives as a new class of SARS-CoV-2 Mpro inhibitors. Structure-activity relationship (SAR) of these compounds was analyzed, which led to the identification of a potent Mpro inhibitor (27h) with an IC50 value of 10.9 nM. The crystal structure of Mpro in complex with 27h revealed that α-ketoamide warhead covalently bound to Cys145s of the protease. In an in vitro antiviral assay, 27h showed excellent activity with an EC50 value of 43.6 nM, comparable to the positive control, Nirmatrelvir. This compound displayed high target specificity for Mpro against human proteases and low toxicity. It also possesses favorable pharmacokinetic properties. Overall, compound 27h could be a promising lead compound for drug discovery targeting SARS-CoV-2 Mpro and deserves further in-depth studies.

Long-term follow-up of methimazole-associated insulin autoimmune syndrome: a rare case report.

Insulin autoimmune syndrome (IAS) is a rare cause of hypoglycemia and is characterized by the presence of insulin autoantibodies and fasting or late postprandial hypoglycemia. The number of reports on the association of long-term follow-up of IAS in China is limited. We herein report a case of drug-induced IAS in a 44-year-old Chinese woman. She had been taking methimazole for Graves' disease and had subsequently presented with recurrent hypoglycemic episodes. Laboratory assessments on admission revealed that her serum insulin level was significantly elevated (>1000 µIU/mL) and that she was positive for serum insulin autoantibody, leading to a diagnosis of IAS. Human leukocyte antigen DNA typing identified *04:06/*09:01:02, an immunogenetic determinant associated with IAS. After treatment with prednisone for 2 months, the hypoglycemic episodes disappeared, her serum insulin level gradually declined, and her insulin antibody levels became negative. Clinicians should be aware of the potential for methimazole to trigger autoimmune hypoglycemia in people with a genetic predisposition.

Generative deep learning enables the discovery of a potent and selective RIPK1 inhibitor.

The retrieval of hit/lead compounds with novel scaffolds during early drug development is an important but challenging task. Various generative models have been proposed to create drug-like molecules. However, the capacity of these generative models to design wet-lab-validated and target-specific molecules with novel scaffolds has hardly been verified. We herein propose a generative deep learning (GDL) model, a distribution-learning conditional recurrent neural network (cRNN), to generate tailor-made virtual compound libraries for given biological targets. The GDL model is then applied to RIPK1. Virtual screening against the generated tailor-made compound library and subsequent bioactivity evaluation lead to the discovery of a potent and selective RIPK1 inhibitor with a previously unreported scaffold, RI-962. This compound displays potent in vitro activity in protecting cells from necroptosis, and good in vivo efficacy in two inflammatory models. Collectively, the findings prove the capacity of our GDL model in generating hit/lead compounds with unreported scaffolds, highlighting a great potential of deep learning in drug discovery.

Lanthanide-Nucleotide Coordination Nanoparticles for STING Activation.

Activation of the stimulator of interferon genes (STING) is essential for blocking viral infections and eliciting antitumor immune responses. Local injection of synthetic STING agonists, such as 2'3'-cGAMP [cGAMP = cyclic 5'-guanosine monophosphate (cGMP)-adenosine monophosphate (AMP)], is a promising approach to enhance antiviral functions and cancer immunotherapy. However, the application of such agonists has been hindered by complicated synthetic procedures, high doses, and unsatisfactory systemic immune responses. Herein, we report the design and synthesis of a series of 2'3'-cGAMP surrogates in nanoparticle formulations formed by reactions of AMP, GMP, and coordinating lanthanides. These nanoparticles can stimulate the type-I interferon (IFN) response in both mouse macrophages and human monocytes. We further demonstrate that the use of europium-based nanoparticles as STING-targeted adjuvants significantly promotes the maturation of mouse bone-marrow-derived dendritic cells and major histocompatibility complex class I antigen presentation. Dynamic molecular docking analysis revealed that these nanoparticles bind with high affinity to mouse STING and human STING. Compared with soluble ovalbumin (OVA), subcutaneously immunized europium-based nanovaccines exhibit significantly increased production of primary and secondary anti-OVA antibodies (∼180-fold) in serum, as well as IL-5 (∼28-fold), IFN-γ (∼27-fold), and IFN-α/ß (∼4-fold) in splenocytes ex vivo. Compared with the 2'3'-cGAMP/OVA formulation, subcutaneous administration of nanovaccines significantly inhibits B16F10-OVA tumor growth and prolongs the survival of tumor-bearing mice in both therapeutic and protective models. Given the rich supramolecular chemistry with lanthanides, this work will enable a readily accessible platform for potent humoral and cellular immunity while opening new avenues for cost-effective, highly efficient therapeutic delivery of STING agonists.

Discovery of benzo[d]oxazol-2(3H)-one derivatives as a new class of TNIK inhibitors for the treatment of colorectal cancer.

Colorectal cancer (CRC) is one of the most commonly diagnosed cancer types and Traf2- and Nck-interacting kinase (TNIK) has been thought as a potential target for CRC treatment. Herein we report the discovery and structure-activity relationship (SAR) of benzo[d]oxazol-2(3H)-one derivatives as a new class of TNIK inhibitors. The most potent compound 8g showed an IC50 value of 0.050 µM against TNIK. It effectively suppressed proliferation and migration of colorectal cancer cells. Western blot analysis indicated that 8g could inhibit aberrant transcription activation of Wnt signaling. Collectively, this study provides a potential lead compound for subsequent drug discovery targeting TNIK.

Glaucocalyxin A Attenuates IL-1ß-Induced Inflammatory Response and Cartilage Degradation in Osteoarthritis Chondrocytes via Inhibiting the Activation of NF-κB Signaling Pathway.

Glaucocalyxin A (GLA) is a bioactive natural compound with anti-inflammatory activity. Herein, the role of GLA in osteoarthritis (OA) was evaluated. Our results demonstrated that the IL-1ß-induced inducible nitric oxide synthase (iNOS) and cyclooygenase-2 (COX-2) expression, two enzymes resulting in the release of nitric oxide (NO) and PGE2, were also prevented by GLA in chondrocytes. Moreover, GLA suppressed inflammatory cytokines production in chondrocytes. In addition, the elevated expressions of MMPs and ADAMTSs and the degradation of aggrecan and collagen II were reversed by GLA in chondrocytes. Furthermore, GLA decreased p-p65 level and suppressed the nuclear p65 accumulation in the nucleus of chondrocytes. Collectively, we concluded that GLA attenuated inflammatory response in chondrocytes via NF-κB pathway. These findings suggested that GLA might become an effective agent for OA treatment.

Discovery of 3,4-Dihydrobenzo[f][1,4]oxazepin-5(2H)-one Derivatives as a New Class of Selective TNIK Inhibitors and Evaluation of Their Anti-Colorectal Cancer Effects.

The Traf2- and Nck-interacting protein kinase (TNIK) is a downstream signal protein of the Wnt/ß-catenin pathway and has been thought of as a potential target for the treatment of colorectal cancer (CRC) that is often associated with dysregulation of Wnt/ß-catenin signaling pathway. Herein, we report the discovery of a series of 3,4-dihydrobenzo[f][1,4]oxazepin-5(2H)-one derivatives as a new class of TNIK inhibitors. Structure-activity relationship (SAR) analyses led to the identification of a number of potent TNIK inhibitors with compound 21k being the most active one (IC50: 0.026 ± 0.008 µM). This compound also displayed excellent selectivity for TNIK against 406 other kinases. Compound 21k could efficiently suppress CRC cell proliferation and migration in in vitro assays and exhibited considerable antitumor activity in the HCT116 xenograft mouse model. It also showed favorable pharmacokinetic properties. Overall, 21k could be a promising lead compound for drug discovery targeting TNIK and deserves further studies.

RIPK1 inhibition enhances the therapeutic efficacy of chidamide in FLT3-ITD positive AML, both in vitro and in vivo.

Acute myeloid leukemia (AML) with FLT3-ITD mutation accounts for a large proportion of relapsed/refractory AML with poor prognosis. RIPK1 is a known key regulator of necroptosis and RIPK1 inhibition shows anti-AML effects in vitro. Chidamide is a histone deacetylase inhibitor (HDACi) with proven ability to induce apoptosis in FLT3-ITD positive AML cells. In the present study, we evaluated the effects of the combination of 22b, a novel RIPK1 inhibitor, and chidamide on proliferation and apoptosis in FLT3-ITD positive AML cell lines and primary cells. The results showed that 22b could significantly enhance the anti-leukemia effect of low-dose chidamide both on cell lines and primary cells. In a subcutaneous xenograft AML model, the combination of 22b and chidamide exhibited obviously elevated anti-tumor activity. In conclusion, our results support that the combination of RIPK1 inhibitor 22b and chidamide may be a novel therapeutic avenue for FLT3-ITD positive AML patients.

Efficacy of mandibular molar distalization by clear aligner treatment. / æ— æ‰˜æ§½éšå½¢çŸ«æ²»å™¨è¿œç§»ä¸‹é¢Œç£¨ç‰™çš„ç–—æ•ˆ.

OBJECTIVES: At present, the research on clear aligner of molar distalization mainly focuses on the upper jaw, while the research on mandibular molars is few.This study aims to evaluate the therapeutic effect of mandibular molars distalization with clear aligner via cone beam CT (CBCT) and Dolphin software. METHODS: Twenty cases of mandibular molars with clear aligner were included according to the inclusion and exclusion criteria. CBCT was taken before treatment (T0) and when the first molar was moved in place (T1). Dolphin software was used to measure the effectiveness of molar distalization. Three-dimensional changes in direction and the impact on the incisors and facial soft and hard tissues were evaluated. RESULTS: The effective rates of crown and root distalization of the second and first mandibular molars were 74%, 49%, and 71%, 47%, respectively. The second and first molars were both the distal buccal cusp with the largest distalization [(2.15 ± 0.91) mm and (1.85±1.09) mm], respectively, with significant difference between the T0 and T1 (P<0.05). The second and first molars were accompanied by depression, distal tilt, and buccal tilt with 1.06 mm, 2.10°, 2.27°, and 0.91 mm, 1.62°, and 1.91°, respectively, with significant differences between the T0 and T1 (all P<0.05). There was no obvious difference between men and women. The mandibular central incisor showed a lip-side movement of 1.02 mm, a depression of 0.82 mm, a mesial incline of 0.66°, and a crown-lip torque of 1.51° after molar distalization, with significant differences between the T0 and T1 (all P<0.001). Only the lower lip thickness increased by 0.1 cm, the length of the lower lip increased by 0.1 cm, and the ANS-ME (distance from anterior nasal spine to submental point) decreased by 0.13 cm, with significant differences between the T0 and T1 (all P<0.05). CONCLUSIONS: Clear aligner can effectively move mandibular molars farther, the crown is more effective than the root, and it is tilted. The second mandibular molar is more effective than the first mandibular molar in its distant displacement and three-dimensional changes. Molar distalization causes minor changes in mandibular incisors and facial soft and hard tissues.

Fe3+-citric acid/sodium alginate hydrogel: A photo-responsive platform for rapid water purification.

As water pollution in human society becomes more and more serious, the demand for materials that can be used for wastewater treatment is increasing. Here, we reported a sodium alginate-based hydrogel (Fe3+-CA/SA hydrogel) that can efficiently photocatalyze the degradation of malachite green. The Fe3+-CA/SA hydrogel is composed of sodium alginate, citric acid, and Fe3+. The hydrogel has multi-leveled pore structure and photochromic ability. Benefiting from the unique microstructure and positive feedback chemical reaction process, the hydrogel has high photocatalytic efficiency. Under 365 nm UV light irradiation, the hydrogel can degrade around 95% of malachite green (20 mg/L) in about 4 min, and there is no need to add H2O2 in the degradation process. The work helps to expand the application of sodium alginate-based hydrogels in the field of water treatment. It also has exploratory significance for the principle of photocatalytic degradation of malachite green.

Identification of Components in Citri Sarcodactylis Fructus from Different Origins via UPLC-Q-Exactive Orbitrap/MS.

To systematically analyze the chemical constituents of Citri Sarcodactylis Fructus (CSF) from different origins, an efficient approach based on ultraperformance liquid chromatography plus Q-Exactive Orbitrap tandem mass spectrometry (UPLC-Q-Exactive Orbitrap/MS) detection for the discrimination of chemical components from of 15 batches of CSF from four main origins was used in this research. Through parent peaks, fragment peaks, fragmentation characteristics, and comparative analysis with the literature and reference standards, a total of 77 components from the methanol extracts including 18 coumarins, 24 flavonoids, seven organic acids, three limonoids, and 25 other compounds were detected and identified. Among them, 15 components have not been reported previously in the CSF. Notably, the stachydrine peak initially showed a higher content in the total ion current chromatogram. Overall, CSF produced in the Zhejiang province contained a richer variety of chemical compositions. These observations provided a theoretical basis for the further quality assessment and application of CSF.

Discovery of 3,4-dihydrobenzo[f][1,4]oxazepin-5(2H)-one derivatives as a new class of ROCK inhibitors for the treatment of glaucoma.

The Rho-associated protein kinases (ROCKs) are associated with the pathology of glaucoma and discovery of ROCK inhibitors has attracted much attention in recent years. Herein, we report a series of 3,4-dihydrobenzo[f][1,4]oxazepin-5(2H)-one derivatives as a new class of ROCK inhibitors. Structure-activity relationship studies led to the discovery of compound 12b, which showed potent activities against ROCK I and ROCK Ⅱ with IC50 values of 93 nM and 3 nM, respectively. 12b also displayed considerable selectivity for ROCKs. The mean IOP-lowering effect of 12b in an ocular normotensive model was 34.3%, and no obvious hyperemia was observed. Overall, this study provides a good starting point for ROCK-targeting drug discovery against glaucoma.

Small molecules in targeted cancer therapy: advances, challenges, and future perspectives.

Due to the advantages in efficacy and safety compared with traditional chemotherapy drugs, targeted therapeutic drugs have become mainstream cancer treatments. Since the first tyrosine kinase inhibitor imatinib was approved to enter the market by the US Food and Drug Administration (FDA) in 2001, an increasing number of small-molecule targeted drugs have been developed for the treatment of malignancies. By December 2020, 89 small-molecule targeted antitumor drugs have been approved by the US FDA and the National Medical Products Administration (NMPA) of China. Despite great progress, small-molecule targeted anti-cancer drugs still face many challenges, such as a low response rate and drug resistance. To better promote the development of targeted anti-cancer drugs, we conducted a comprehensive review of small-molecule targeted anti-cancer drugs according to the target classification. We present all the approved drugs as well as important drug candidates in clinical trials for each target, discuss the current challenges, and provide insights and perspectives for the research and development of anti-cancer drugs.

SARS-CoV-2 Mpro inhibitors with antiviral activity in a transgenic mouse model.

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continually poses serious threats to global public health. The main protease (Mpro) of SARS-CoV-2 plays a central role in viral replication. We designed and synthesized 32 new bicycloproline-containing Mpro inhibitors derived from either boceprevir or telaprevir, both of which are approved antivirals. All compounds inhibited SARS-CoV-2 Mpro activity in vitro, with 50% inhibitory concentration values ranging from 7.6 to 748.5 nM. The cocrystal structure of Mpro in complex with MI-23, one of the most potent compounds, revealed its interaction mode. Two compounds (MI-09 and MI-30) showed excellent antiviral activity in cell-based assays. In a transgenic mouse model of SARS-CoV-2 infection, oral or intraperitoneal treatment with MI-09 or MI-30 significantly reduced lung viral loads and lung lesions. Both also displayed good pharmacokinetic properties and safety in rats.

Epidemiological and clinical characteristics of a familial cluster of COVID-19.

We report a family cluster of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection involving five patients in a family cluster in Dazhou, China, including the epidemiological, clinical, laboratory and radiological findings. Three-generation transmission was observed. Through epidemiological investigation, we observed asymptomatic transmission to a cohabiting family member, as well as person-to-person transmission of SARS-CoV-2 outside Wuhan city. The asymptomatic transmission demonstrated here provides evidence that there could be a greater risk of Coronavirus Disease 2019 (COVID-19) spread. This cluster also demonstrated that COVID-19 is transmissible during the incubation period of an asymptomatic person. Early isolation and treatment, stressing prevention of cluster outbreaks, could help prevent further spread of the epidemic.

Transparent Stretchable Dual-Network Ionogel with Temperature Tolerance for High-Performance Flexible Strain Sensors.

A stretchable transparent double network ionogel composed of physically cross-linked poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-co-HFP)) and chemically cross-linked poly(methyl methacrylate-co-butylmethacrylate) (P(MMA-co-BMA)) elastomer networks within [EMIM][TFSI] ionic liquid was fabricated through a facile one-pot thermal polymerization. The dual-network (DN) ionogel presents good mechanical performance (failure tensile stress 2.31 MPa, strain 307%) with a high loading of ionic liquid (70 wt %) for achieving required ionic conductivity (>0.1 S/m at room temperature). The transparent chemical cross-linked P(MMA-co-BMA) elastomer network endows high transparency (>93%) and high stretchability to the DN ionogel. The DN ionogel maintains good toughness, elasticity, and transparency in a wide temperature range (-40 to 80 °C) for the application in a harsh environment. In addition, the sensitivity of the DN ionogel to the change of environment temperature and deformation was detected and described. The practical potential of the DN ionogel in flexible electronic devices is further revealed by fabricating DN ionogel strain sensors to detect the movement of different human limbs including the bending of the finger, wrist, and elbow as well as the slight throat jitter during the swallowing and vocalization, showing fast response, high sensitivity, and good repeatability.

UPLC-Q-Exactive Orbitrap MS Analysis for Identification of Lipophilic Components in Citri Sarcodactylis Fructus from Different Origins in China Using Supercritical CO2 Fluid Extraction Method.

To thoroughly evaluate the quality of Citri Sarcodactylis Fructus (CSF) and acquire knowledge of the lipophilic components of CSF from different origins, a simple and efficient approach based on supercritical fluid extraction (SFE) combined with ultraperformance liquid chromatography plus Q-Exactive Orbitrap tandem mass spectrometry (UPLC-Q-Exactive Orbitrap/MS) detection for the discrimination of components from CSF was set up for the first time in this work. Eight batches of CSF samples from five main producing areas were extracted by SFE under optimized conditions, and then SFE extracts were dissected via UPLC-Q-Exactive Orbitrap/MS. The results indicated that 39 lipophilic compounds were successfully separated and unambiguously or tentatively identified, where 4 coumarins, 6 polymethoxyflavones, 3 phthalides, 6 terpenes, and 4 phenolics were not reported formerly. It was illustrated that CSF may be abundant in polymethoxyflavones, as in coumarins. Moreover, there were significant differences in the components of CSF from different origins. Especially, coumarin, dehydrocostus lactone, atractylenolide II, and atractylenolide I were exclusively found in CSF from the Guangdong province; isopsoralen was almost exclusively found in CSF from the Guangxi province; and ferulic acid was exclusively found in CSF from the Zhejiang province. These observations indicated that SFE joint with UPLC-Q-Exactive Orbitrap/MS owing to the potential of characterizing the lipophilic components could be used to promote quality assessment and chemotaxonomic investigation in phytology sciences of CSF.