Palladium(II)-Catalyzed Tandem γ-C(sp2)-H Arylation and Cyclization for the Construction of Natural Product-Like Polycyclic Fused ortho-Quinone Scaffolds.

Here, we report a novel strategy for the direct construction of polycyclic fused ortho-quinone scaffolds through palladium(II)-catalyzed tandem γ-C(sp2)-H arylation and cyclization of arylglyoxals with aryl iodides. This transformation features unique tandem transient directing of γ-C(sp2)-H arylation and cyclization reaction mode, broad substrate scope, especially for the aromatic substrates containing oxygen and sulfur atoms, and avoiding the common issue of aromatization due to the construction of the hexatomic ring.

Short-term regulation of TSFM level does not alter amyloidogenesis and mitochondrial function in type-specific cells.

BACKGROUND: Mitochondrial Ts translation elongation factor (TSFM) is an enzyme that catalyzes exchange of guanine nucleotides. By forming a complex with mitochondrial Tu translation elongation factor (TUFM), TSFM participates in mitochondrial protein translation. We have previously reported that TUFM regulates translation of beta-site APP cleaving enzyme 1 (BACE1) via ROS (reactive oxygen species)-dependent mechanism, suggesting a potential role in amyloid precursor protein (APP) processing associated with Alzheimer's disease (AD), which led to the speculation that TSFM may regulate APP processing in a similar way to TUFM. METHODS AND RESULTS: Here, we report that in cultured cells, knockdown or overexpression TSFM did not change protein levels in BACE1 and APP. Besides, the levels of cytoplasmic ROS and mitochondrial superoxide, in addition to ATP level, cell viability and mitochondrial membrane potential were not significantly altered by TSFM knockdown in the short term. Further transcriptome analysis revealed that expression of majority of mitochondrial genes were not remarkably changed by TSFM silencing. The possibility of TSFM involved in cardiomyopathy and cancer development was uncovered using bioinformatics analysis. CONCLUSIONS: Collectively, short-term regulation of TSFM level in cultured cells does not cause a significant change in proteins involved in APP processing, levels in ROS and ATP associated with mitochondrial function. Whereas our study could contribute to comprehend certain clinical features of TSFM mutations, the roles of TSFM in cardiomyopathy and cancer development might deserve further investigation.

Structure-based design of pan-coronavirus inhibitors targeting host cathepsin L and calpain-1.

Respiratory disease caused by coronavirus infection remains a global health crisis. Although several SARS-CoV-2-specific vaccines and direct-acting antivirals are available, their efficacy on emerging coronaviruses in the future, including SARS-CoV-2 variants, might be compromised. Host-targeting antivirals provide preventive and therapeutic strategies to overcome resistance and manage future outbreak of emerging coronaviruses. Cathepsin L (CTSL) and calpain-1 (CAPN1) are host cysteine proteases which play crucial roles in coronaviral entrance into cells and infection-related immune response. Here, two peptidomimetic α-ketoamide compounds, 14a and 14b, were identified as potent dual target inhibitors against CTSL and CAPN1. The X-ray crystal structures of human CTSL and CAPN1 in complex with 14a and 14b revealed the covalent binding of α-ketoamide groups of 14a and 14b to C25 of CTSL and C115 of CAPN1. Both showed potent and broad-spectrum anticoronaviral activities in vitro, and it is worth noting that they exhibited low nanomolar potency against SARS-CoV-2 and its variants of concern (VOCs) with EC50 values ranging from 0.80 to 161.7 nM in various cells. Preliminary mechanistic exploration indicated that they exhibited anticoronaviral activity through blocking viral entrance. Moreover, 14a and 14b exhibited good oral pharmacokinetic properties in mice, rats and dogs, and favorable safety in mice. In addition, both 14a and 14b treatments demonstrated potent antiviral potency against SARS-CoV-2 XBB 1.16 variant infection in a K18-hACE2 transgenic mouse model. And 14b also showed effective antiviral activity against HCoV-OC43 infection in a mouse model with a final survival rate of 60%. Further evaluation showed that 14a and 14b exhibited excellent anti-inflammatory effects in Raw 264.7 mouse macrophages and in mice with acute pneumonia. Taken together, these results suggested that 14a and 14b are promising drug candidates, providing novel insight into developing pan-coronavirus inhibitors with antiviral and anti-inflammatory properties.

Investigation and Improvement of Test Methods for Capacitance and DCESR of EDLC Cells.

The quick and accurate characterization of commercial electrochemical double-layer capacitor (EDLC) cells, especially their capacitance and direct-current equivalent series internal resistance (DCESR), is of great significance for the design, maintenance, and monitoring of EDLCs used in areas of energy, sensors, electric power, construction machinery, rail transit, automobile transportation, and military. In this study, the capacitance and DCESR of three commercial EDLC cells with similar performance were determined and compared by following the three commonly-used standards of IEC 62391, Maxwell, and QC/T741-2014, which are significantly different in test procedures and calculation methods. The analysis of the test procedures and results demonstrated that the IEC 62391 standard has the disadvantages of a large testing current, long testing time, and a complex and inaccurate DCESR calculation, whereas the Maxwell standard has the disadvantages of a large testing current, a small capacitance, and large DCESR testing results, and furthermore the QC/T 741 standard has the disadvantages of a high resolution requirement for the equipment and small DCESR results. Therefore, an improved method was proposed to determine the capacitance and DCESR of EDLC cells by short-time constant voltage charging and discharging interruption methods, respectively, with the advantages of high accuracy, low equipment requirements, short testing time, and the easy calculation of DCESR over the original three standards.

Clinical application of SARS-CoV-2 antibody detection and monoclonal antibody therapies against COVID-19.

The purpose of this study was to investigate the clinical application of severe acute respiratory distress syndrome coronavirus-2 (SARS-CoV-2) specific antibody detection and anti-SARS-CoV-2 specific monoclonal antibodies (mAbs) in the treatment of coronavirus infectious disease 2019 (COVID-19). The dynamic changes of SARS-CoV-2 specific antibodies during COVID-19 were studied. Immunoglobulin M (IgM) appeared earlier and lasted for a short time, while immunoglobulin G (IgG) appeared later and lasted longer. IgM tests can be used for early diagnosis of COVID-19, and IgG tests can be used for late diagnosis of COVID-19 and identification of asymptomatic infected persons. The combination of antibody testing and nucleic acid testing, which complement each other, can improve the diagnosis rate of COVID-19. Monoclonal anti-SARS-CoV-2 specific antibodies can be used to treat hospitalized severe and critically ill patients and non-hospitalized mild to moderate COVID-19 patients. COVID-19 convalescent plasma, highly concentrated immunoglobulin, and anti-SARS-CoV-2 specific mAbs are examples of anti-SARS-CoV-2 antibody products. Due to the continuous emergence of mutated strains of the novel coronavirus, especially omicron, its immune escape ability and infectivity are enhanced, making the effects of authorized products reduced or invalid. Therefore, the optimal application of anti-SARS-CoV-2 antibody products (especially anti-SARS-CoV-2 specific mAbs) is more effective in the treatment of COVID-19 and more conducive to patient recovery.

O-GlcNAcylation of RAB10 promotes hepatocellular carcinoma progression.

Ras-related protein Rab-10 (RAB10) is involved in tumorigenesis and progression of hepatocellular carcinoma (HCC). Here, we found RAB10, O-GlcNAc transferase (OGT), and O-GlcNAcylation were upregulated in HCC. In addition, RAB10 protein level was prominently positively correlated with the expression of OGT. O-GlcNAcylation modification of RAB10 was then investigated. Here we showed that RAB10 interacts directly with OGT in HCC cell lines, Meanwhile, O-GlcNAcylation enhanced RAB10 protein stability. Furthermore, knockdown of OGT suppressed aggressive behaviors of HCC in vitro and in vivo, while elevated RAB10 reversed these. Taken together, these results indicated that OGT mediated O-GlcNAcylation stabilized RAB10, thus accelerating HCC progression.

Synthesis of maleimide-braced peptide macrocycles and their potential anti-SARS-CoV-2 mechanisms.

Macrocycles often exhibit good biological properties and potential druggability, which lead to versatile applications in the pharmaceutical industry. Herein, we report a highly efficient and practical methodology for the functionalization and macrocyclization of Trp and Trp-containing peptides via Pd(II)-catalyzed C-H alkenylation at the Trp C4 position. This method provides direct access to C4 maleimide-decorated Trp-containing peptidomimetics and maleimide-braced 17- to 30-membered peptide macrocycles. In particular, these unique macrocycles revealed low micro- to sub-micromolar EC50 values with promising anti-SARS-CoV-2 activities. Further explorations with computational methodologies and experimental validations indicated that these macrocycles exert antiviral effects through binding with the N protein of SARS-CoV-2.

Structure-Based Design of Tropane Derivatives as a Novel Series of CCR5 Antagonists with Broad-Spectrum Anti-HIV-1 Activities and Improved Oral Bioavailability.

Blocking the entry of an HIV-1 targeting CCR5 coreceptor has emerged as an attractive strategy to develop HIV therapeutics. Maraviroc is the only CCR5 antagonist approved by FDA; however, serious side effects limited its clinical use. Herein, 21 novel tropane derivatives (6-26) were designed and synthesized based on the CCR5-maraviroc complex structure. Among them, compounds 25 and 26 had comparable activity to maraviroc and presented more potent inhibitory activity against a series of HIV-1 strains. In addition, compound 26 exhibited synergistic or additive antiviral effects in combination with other antiretroviral agents. Compared to maraviroc, both 25 and 26 displayed higher Cmax and AUC0-∞ and improved oral bioavailability in SD rats. In addition, compounds 25 and 26 showed no significant CYP450 inhibition and showed a novel binding mode with CCR5 different from that of maraviroc-CCR5. In summary, compounds 25 and 26 are promising drug candidates for the treatment of HIV-1 infection.

In vitro and in vivo evaluation of the main protease inhibitor FB2001 against SARS-CoV-2.

FB2001 is a drug candidate that targets the main protease of SARS-CoV-2 via covalently binding to cysteine 145. In this study, we evaluated the inhibitory activities of FB2001 against several SARS-CoV-2 variants in vitro and in vivo (in mice), and we also evaluated the histopathological analysis and immunostaining of FB2001 on lung and brain which have been rarely reported. The results showed that FB2001 exhibited potent antiviral efficacy against several current SARS-CoV-2 variants in Vero E6 cells, namely, B.1.1.7 (Alpha): EC50 = 0.39 ± 0.01 µM, EC90 = 0.75 ± 0.01 µM; B.1.351 (Beta): EC50 = 0.28 ± 0.11 µM, EC90 = 0.57 ± 0.21 µM; B.1.617.2 (Delta): EC50 = 0.27 ± 0.05 µM, EC90 = 0.81 ± 0.20 µM; B.1.1.529 (Omicron): EC50 = 0.26 ± 0.06 µM and EC50 = 0.042 ± 0.007 µM (in the presence of a P-glycoprotein inhibitor). FB2001 remained potent against SARS-CoV-2 replication in the presence of high concentrations of human serum, which indicating that human serum had no significant effect on the in vitro inhibitory activity. Additionally, this inhibitor exhibited an additive effect against SARS-CoV-2 when combined with Remdesivir. Furthermore, FB2001 significantly reduced the SARS-CoV-2 copy numbers and titers in the lungs and brains in vivo, and alleviated the pathological symptoms. In addition, FB2001 could alleviated local bleeding, erythrocyte overflow, edema, and inflammatory cell infiltration in brain tissue, and inhibitors reducing viral titers and improving inflammation in the brain have been rarely reported. A physiologically based pharmacokinetic model was established and verified to predict the FB2001 concentration in human lungs. When FB2001 was administered at 200 mg twice a day for 5 days, the observed Ctrough ss in plasma and predicted Ctrough ss of lung total concentration were 0.163 and 2.5 µg/mL, which were approximately 9 and 132-fold higher than the EC50 of 0.019 µg/mL (0.042 µM) against Omicron variant. Taken together, our study suggests that FB2001 is a promising therapeutic agent in COVID-19 treatment and can be combined with remdesivir to achieve improved clinical outcomes. Owing to its good safety and tolerability in healthy human (NCT05197179 and NCT04766931), FB2001 has been approved for Phase II/III clinical trial (NCT05445934).

Underwater image restoration via background light estimation and depth map optimization.

In underwater images, the significant sources of distortion are light attenuation and scattering. Existing underwater image restoration technologies cannot deal with the poor contrast and color distortion bias of underwater images. This work provides a new underwater image restoration approach relying on depth map optimization and background light (BL) estimation. First, we build a robust BL estimation model that relies on the prior features of blurriness, smoothness, and the difference between the intensity of the red and blue-green channels. Second, the red-light intensity, difference between light and dark channels, and disparity of red and green-blue channels by considering the hue are used to calculate the depth map. Then, the effect of artificial light sources on the underwater image is removed using the adjusted reversed saturation map. Both the subjective and objective experimental results reveal that the images produced by the proposed technology provide more remarkable visibility and superior color fidelity.

Corrigendum: New Prediction Models of Functional Outcome in Acute Intracerebral Hemorrhage: The dICH Score and uICH Score.

[This corrects the article DOI: 10.3389/fneur.2021.655800.].

Underwater image restoration by red channel compensation and underwater median dark channel prior.

Underwater images often show low contrast, blurring, and color distortion due to the absorption and scattering of light. In contrast to existing underwater image restoration methods, we propose an underwater image restoration method with red channel compensation and blue-green channel restoration. First, a proposed approach relies on the hue and attenuation differences between different color channels of the underwater image to estimate the background light. Then, the red channel is enhanced according to a perfect reflection assumption algorithm. Finally, a new median underwater dark channel prior (MUDCP) is proposed to precisely estimate the blue-green channel transmission map. Experimental results show that our method significantly improves contrast, removes color bias, and preserves more detail than other underwater restoration techniques.

Novel Sphingosine Kinase 1 Inhibitor Suppresses Growth of Solid Tumor and Inhibits the Lung Metastasis of Triple-Negative Breast Cancer.

Targeting sphingosine kinase 1 (SphK1) has become a novel strategy for the treatment of inflammatory bowel disease and cancer via the SphK1/S1P signaling pathway. However, exploration of SphK1 inhibitor therapeutic applications has been hampered by the poor pharmacokinetic properties of these SphK1 inhibitors. Herein, we report the structural optimization and structure-activity relationship studies of a series of novel SphK1 inhibitors. The novel compound 28 selectively inhibits SphK1 and exhibits higher anti-proliferative activity compared to the positive compound PF-543 in various cancer cells, which is associated with the induction of G0/G1 phase arrest and apoptosis; besides, it could also inhibit the cell migration. Further, compound 28 can suppress in vivo growth of both colon tumor and triple-negative breast tumor and inhibits the lung metastasis of triple-negative breast cancer with higher potency compared with that of PF-543. Collectively, compound 28 represents a promising lead compound for the treatment of solid tumor and the metastasis.

Early Perihematomal Edema Expansion: Definition, Significance, and Association with Outcomes after Intracerebral Hemorrhage.

OBJECTIVE: To investigate the association between early perihematomal edema (PHE) expansion and functional outcome in patients with intracerebral hemorrhage (ICH). METHODS: Patients with ICH who underwent initial computed tomography (CT) scans within 6 hours after the onset of symptoms and follow-up CT scans within 24 ± 12 hours were included. Absolute PHE increase was defined as the absolute increase in PHE volume from baseline to 24 hours. A receiver-operating characteristic (ROC) curve was generated to determine the cutoff value for early PHE expansion, which was operationally defined as an absolute increase in PHE volume of >6 mL. The outcome of interest was 3-month poor outcome defined as modified Rankin scale score of ≥4. A multivariable logistic regression procedure was used to assess the association between early PHE expansion and outcome after ICH. RESULTS: In 233 patients with ICH, 89 (38.2%) patients had poor outcome at 3-month follow-up. Early PHE expansion was observed in 56 of 233 (24.0%) patients. Patients with early PHE expansion were more likely to have poor functional outcome than those without (43.8% vs. 11.8%, p < 0.001). After adjusting for age, admission systolic blood pressure, admission Glasgow Coma Scale score, baseline ICH volume and the presence of intraventricular hemorrhage, and time from onset to CT, early PHE expansion was associated with poor outcome (adjusted odds ratio, 4.25; 95% confidence interval, 1.70-10.60; p = 0.002). CONCLUSIONS: The early PHE expansion was not uncommon in patients with ICH and was correlated with poor outcome following ICH.

Direct C4-Acetoxylation of Tryptophan and Tryptophan-Containing Peptides via Palladium(II)-Catalyzed C-H Activation.

An efficient regioselective palladium(II)-catalyzed C(sp2)-H 4-acetoxylation of tryptophan and tryptophan-containing peptides is described. This transformation achieves the direct construction of C-O bonds at the tryptophan C4-position and features good functional group tolerance. The 4-hydroxyl compound was obtained by removing acetyl after C4-acetoxylation of tryptophan derivatives and tryptophan-containing dipeptides. This method provides a novel strategy for the synthesis of 4-substituted tryptophan derivatives and modification of tryptophan-containing peptides.

New Prediction Models of Functional Outcome in Acute Intracerebral Hemorrhage: The dICH Score and uICH Score.

Objectives: The original intracerebral hemorrhage (oICH) score is the severity score most commonly used in clinical intracerebral hemorrhage (ICH) research but may be influenced by hematoma expansion or intraventricular hemorrhage (IVH) growth in acute ICH. Here, we aimed to develop new clinical scores to improve the prediction of functional outcomes in patients with ICH. Methods: Patients admitted to the First Affiliated Hospital of Chongqing Medical University with primary ICH were prospectively enrolled in this study. Hematoma volume was measured using a semiautomated, computer-assisted technique. The dynamic ICH (dICH) score was developed by incorporating hematoma expansion and IVH growth into the oICH score. The ultra-early ICH (uICH) score was developed by adding the independent non-contrast CT markers to the oICH score. Receiver operating characteristic curve analysis was used to compare performance among the oICH score, dICH score, and uICH score. Results: This study included 76 patients (23.3%) with hematoma expansion and 61 patients (18.7%) with IVH growth. Of 31 patients with two or more non-contrast computed tomography markers, 61.3% died, and 96.8% had poor outcomes at 90 days. After adjustment for potential confounding variables, we found that age, baseline Glasgow Coma Scale score, presence of IVH on initial CT, baseline ICH volume, infratentorial hemorrhage, hematoma expansion, IVH growth, blend sign, black hole sign, and island sign could independently predict poor outcomes in multivariate analysis. In comparison with the oICH score, the dICH score and uICH score exhibited better performance in the prediction of poor functional outcomes. Conclusions: The dICH score and uICH score were useful clinical assessment tools that could be used for risk stratification concerning functional outcomes and provide guidance in clinical decision-making in acute ICH.

Noncontrast Computed Tomography Markers as Predictors of Revised Hematoma Expansion in Acute Intracerebral Hemorrhage.

Background Noncontrast computed tomography (NCCT) markers are the emerging predictors of hematoma expansion in intracerebral hemorrhage. However, the relationship between NCCT markers and the dynamic change of hematoma in parenchymal tissues and the ventricular system remains unclear. Methods and Results We included 314 consecutive patients with intracerebral hemorrhage admitted to our hospital from July 2011 to May 2017. The intracerebral hemorrhage volumes and intraventricular hemorrhage (IVH) volumes were measured using a semiautomated, computer-assisted technique. Revised hematoma expansion (RHE) was defined by incorporating the original definition of hematoma expansion into IVH growth. Receiver operating characteristic curve analysis was used to compare the performance of the NCCT markers in predicting the IVH growth and RHE. Of 314 patients in our study, 61 (19.4%) had IVH growth and 93 (23.9%) had RHE. After adjustment for potential confounding variables, blend sign, black hole sign, island sign, and expansion-prone hematoma could independently predict IVH growth and RHE in the multivariate logistic regression analysis. Expansion-prone hematoma had a higher predictive performance of RHE than any single marker. The diagnostic accuracy of RHE in predicting poor prognosis was significantly higher than that of hematoma expansion. Conclusions The NCCT markers are independently associated with IVH growth and RHE. Furthermore, the expansion-prone hematoma has a higher predictive accuracy for prediction of RHE and poor outcome than any single NCCT marker. These findings may assist in risk stratification of NCCT signs for predicting active bleeding.

Hydrocephalus Growth: Definition, Prevalence, Association with Poor Outcome in Acute Intracerebral Hemorrhage.

BACKGROUND/OBJECTIVES: To propose a novel definition for hydrocephalus growth and to further describe the association between hydrocephalus growth and poor outcome among patients with intracerebral hemorrhage (ICH). METHODS: We analyzed consecutive patients who presented within 6 h after ICH ictus between July 2011 and June 2017. Follow-up CT scans were performed within 36 h after initial CT scans. The degree of hydrocephalus were evaluated by the hydrocephalus score of Diringer et al. The optimal increase of the hydrocephalus scores between initial and follow-up CT scan was estimated to define hydrocephalus growth. Poor long-term outcome was defined as a modified Rankin Scale of 4-6 at 3 months. Multivariate logistic regression analysis was performed to investigate the hydrocephalus growth for predicting 30-day mortality, 90-day mortality, and poor long-term outcome. RESULTS: A total of 321 patients with ICH were included in the study. Of 64 patients with hydrocephalus growth, 34 (53.1%) patients presented with both concurrent hematoma expansion and intraventricular hemorrhage (IVH) growth. After adjusting for potential confounding factors, hydrocephalus growth independently predicted 30-day mortality, 90-day mortality, and 90-day poor long-term outcome in multivariate logistic regression analysis. Hydrocephalus growth showed higher accuracy for predicting 30-day mortality, 90-day mortality, and poor long-term outcome than IVH growth or hematoma expansion, respectively. CONCLUSIONS: Hydrocephalus growth is defined by strongly predictive of short- or long-term mortality and poor outcome at 90 days, and might be a potential indicator for assisting clinicians for clinical decision-making.

The slice score: A novel scale measuring intraventricular hemorrhage severity and predicting poor outcome following intracerebral hemorrhage.

OBJECTIVES: To quantify extent of intraventricular hemorrhage (IVH) following intracerebral hemorrhage (ICH) with a novel, simple IVH severity score, and to explore and compare its performance in predicting worse outcomes. PATIENTS AND METHODS: A new scoring system for IVH severity was proposed and termed Slice score. The Slice score features non-septum pellucidum section, internal capsule section, third ventricle occipital horn section, three standardized scans for scoring the lateral ventricles. 652 scans from 326 subjects were retrospectively analyzed. The correlations between measured IVH volume and Slice score, original Graeb, LeRoux, and IVH score (IVHS) were compared. The association between these scores and clinical outcomes were evaluated using logistic regression. We then identified clinical thresholds of Slice score by balancing the probability of prediction and accuracy. Primary outcome was defined as 90-day poor outcome (modified Rankin Scale score ≥ 4) and secondary outcome was 90-day mortality. RESULTS: Of 326 ICH patients, 122 (37.4%) had poor outcome and 59 (18.1%) died at 3 months. The Slice score showed the highest correlation with measured IVH volume (R = 0.73, R2 = 0.54, p < 0.001). The observed area under the curve were similar among the Slice, original Graeb, LeRoux score, and IVH score for poor outcome (0.633, 0.633, 0.632, 0.634, respectively), and for mortality (0.660, 0.660, 0.660, 0.656, respectively). All IVH scales were independently associated with 90-day poor outcome and mortality with close odds ratio in adjusted models (all odds ratio > 1.07, all p < 0.05). Multivariable Analyses of categorized Slice score revealed optimal thresholds of 6 and 12 for primary and secondary outcomes (odds ratio 4.20, 95% confidence interval 1.82-10.02, p = 0.001; odds ratio 5.41, 95% confidence interval 1.66-17.43, p = 0.005, respectively). CONCLUSIONS: The Slice score correlated highly with the IVH volume, was a reliable volumetric scale for measuring IVH severity, and could be an easy-to-use tool for predicting 90-day poor outcome and mortality in ICH.

Structure-based design of antiviral drug candidates targeting the SARS-CoV-2 main protease.

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is the etiological agent responsible for the global COVID-19 (coronavirus disease 2019) outbreak. The main protease of SARS-CoV-2, Mpro, is a key enzyme that plays a pivotal role in mediating viral replication and transcription. We designed and synthesized two lead compounds (11a and 11b) targeting Mpro Both exhibited excellent inhibitory activity and potent anti-SARS-CoV-2 infection activity. The x-ray crystal structures of SARS-CoV-2 Mpro in complex with 11a or 11b, both determined at a resolution of 1.5 angstroms, showed that the aldehyde groups of 11a and 11b are covalently bound to cysteine 145 of Mpro Both compounds showed good pharmacokinetic properties in vivo, and 11a also exhibited low toxicity, which suggests that these compounds are promising drug candidates.