Novel 6-amino-1,3,5-triazine derivatives as potent BTK inhibitors: structure-activity relationship (SAR) analysis and preliminary mechanism investigation.

Bruton's tyrosine kinase (BTK) is a promising drug target for the treatment of B-cell related malignancies. Irreversible inhibition of BTK by a covalent inhibitor has been proved to be a clinically effective therapy. However, most irreversible BTK inhibitors also inhibit other kinases including JAK3 and EGFR, leading to some adverse events. Herein, we reported the structure-based design and optimization of a series of irreversible BTK inhibitors bearing the 6-amino-1,3,5-triazine scaffold. Most of the synthesized compounds demonstrated considerable BTK inhibition and improved anti-proliferative activity against Raji and Ramos cells. Among them, compound C11 exhibited potent BTK inhibition (BTK IC50 = 17.0 nM) and a desirable selectivity profile especially over EGFR. Moreover, C11 effectively blocked activation of BTK and downstream signaling, arrested the cell cycle in G0/G1 phase and induced apoptosis in Raji cells. Its irreversible binding mode was further investigated by both molecular modeling and a washout experiment. Collectively, C11 is a novel selective irreversible BTK inhibitor worthy of further in-depth research.

Structural optimization of tetrahydroisoquinoline-hydroxamate hybrids as potent dual ERα degraders and HDAC inhibitors.

Both estrogen receptor α (ERα) and histone deacetylases (HDACs) are valid therapeutic targets for anticancer drug development. Combination therapies using diverse ERα antagonists or degraders and HDAC inhibitors have been proven effective in endocrine-resistant ER + breast cancers based on the crosstalk between ERα and HDAC pathway. In this study, we reported the optimization of a series of methoxyphenyl- or pyridinyl- substituted tetrahydroisoquinoline-hydroxamates, which were optimized from 31, a dual ERα degrader/HDAC inhibitor previously reported by our group. Most of the synthesized compounds displayed potent ERα degradation efficacy and antiproliferative activity. Among them, A04 demonstrated the best anti-proliferation activity (MCF-7 IC50 = 1.96 µM) and HDAC6 inhibitory activity (HDAC6 IC50 = 25.96 nM), which is slightly more potent than the lead compound 31 (MCF-7 IC50 = 4.38 µM, HDAC6 IC50 = 63.03 nM). In addition, compound A04 exerted ERα-independent HDAC6-inhibiting effect without agonistic activity in endometrial cells. These results demonstrated that A04 is a novel and promising dual ERα degrader/HDAC inhibitor worthy of further development.

High-Coverage Quantitative Metabolomics of Human Urine: Effects of Freeze-Thaw Cycles on the Urine Metabolome and Biomarker Discovery.

Urine sample storage after collection at ultra-low-temperature (e.g., -80 °C) is normally required for comparative metabolome analysis of many samples, and therefore, freeze-thaw cycles (FTCs) are unavoidable. However, the reported effects of FTCs on the urine metabolome are controversial. Moreover, there is no report on the study of how urine FTCs affect biomarker discovery. Herein, we present our study of the FTC effects on the urine metabolome and biomarker discovery using a high-coverage quantitative metabolomics platform. Our study involved two centers located in Hangzhou, China, and Edmonton, Canada, to perform metabolome analysis of two separate cohorts of urine samples. The same workflow of sample preparation and dansylation isotope labeling LC-MS was used for in-depth analysis of the amine/phenol submetabolome. The analysis of 320 samples from the Hangzhou cohort consisting of 80 healthy subjects with each urine being subjected to four FTCs resulted in relative quantification of 3682 metabolites with 3307 identified or mass-matched. The analysis of 176 samples from the Edmonton cohort of 44 subjects with four FTCs quantified 3516 metabolites with 3166 identified or mass-matched. Multivariate and univariate analyses indicated that significant variations (fold change ≥ 1.5 with q-value ≤ 0.05) from FTCs were only observed in a very small fraction of the metabolites (<0.3%). Moreover, various metabolites did not show a consistent pattern of concentration changes from one to four FTCs, allowing the use of two separate cohorts of samples to remove these randomly changed metabolites. Three metabolite biomarkers for separating males and females were discovered, and FTC did not influence their discovery.

Cavity-dumped burst-mode Nd:YAG laser master-oscillator power-amplifier system with a flat-top beam output realized by gain profile-controlled side pumping.

We report a compact cavity-dumped burst-mode Nd:YAG laser master-oscillator power-amplifier system with a flat-top intensity distribution across the output-beam section. Custom-designed gain profile-controlled diode side pumping modules providing flat-top and concave gain profiles were utilized to generate a uniform beam profile and suppress thermal lensing during amplification, respectively. Bursts with an energy of 2.0 J and duration of 1.6 ms were operated at 10 Hz. Within the bursts, single pulses with an energy of 12.7 mJ and pulse width of 3.3 ns were achieved at 100 kHz.

5 kHz, 4.2mJ, 900 ps end-pumped Nd:YVO4 MOPA laser system.

A 5 kHz sub-nanosecond master oscillator power amplifier (MOPA) laser system was reported in this paper. The master oscillator was an electro-optically Q-switched Nd:YVO4 laser directly pumped at 879 nm, yielding a pulse energy of 520 µJ and a pulse width of 900 ps at 5 kHz. With two Nd:YVO4 amplifiers directly pumped at 914 nm, the pulse energy was further scaled up. Under the absorbed pump energy of 11.0 mJ, the pulse energy was amplified to 4.2 mJ, corresponding to a peak power of 4.7 MW. The optical-to-optical efficiency of the amplifiers reached 33.5%.

Metabolic perturbations in human hepatocytes induced by bis (2-ethylhexyl)-2,3,4,5-tetrabromophthalate exposure: Insights from high-coverage quantitative metabolomics.

Bis (2-ethylhexyl)-2,3,4,5-tetrabromophthalate (TBPH) is an extensively used novel brominated flame retardant that is present ubiquitously in the environment and in biota. However, there is inadequate data on its potential hepatotoxicity to humans. In this study, high-coverage quantitative metabolomics based on 12C-/13C-dansylation labeling LC-MS was performed for the first time to assess the metabolic perturbations and underlying mechanisms of TBPH on human hepatocytes. HepG2 cells were exposed to TBPH at dosages of 0.1,1,10 µM for 24 or 72 h. Overall, 1887 and 1364 amine/phenol-containing metabolites were relatively quantified in cells and culture supernatant. Our results revealed that exposure to 0.1 µM TBPH showed little adverse effects, whereas exposure to 10 µM TBPH for 24 h enhanced intracellular protein catabolism and disrupted energy and lipid homeostasis-related pathways such as histidine metabolism, pantothenate and CoA biosynthesis, alanine, aspartate and glutamate metabolism. Nevertheless, most of these perturbations returned to the same levels as controls after 72 h of exposure. Additionally, prolonged TBPH exposure increased oxidative stress, as reflected by marked disturbances in taurine metabolism. This study sensitively revealed the dysregulations of intracellular and extracellular metabolome induced by TBPH, providing a comprehensive understanding of metabolic responses of cells to novel brominated flame retardants.

Dynamic alterations of metabolites revealed the vascularization progression of bioengineered liver.

Vascularization is a critical but challenging process in developing functional bioengineered livers with the decellularized liver scaffolds (DLSs) and the process is accompanied by cell-specific metabolic alterations. To elucidate the dynamic alterations of metabolites during vascularization, rat DLSs were vascularized with human umbilical vein endothelial cells and liquid chromatography mass spectrometry-based metabolomics was performed on culture supernatants collected at 0, 1, 3, 7, 14, and 21 days. Overall, 1698 peak pairs or metabolites were detected in the culture supernatants, with 309 metabolites being positively identified. The orthogonal partial least-squares discriminant analysis and functional enrichment analysis revealed three phases that could be clearly discriminated, including Phase D1 (cell proliferation and migration), Phase D3D7 (vascular lumen formation), and Phase D14D21 (functional endothelial barrier formation). Seventy-two common differentially abundant metabolites of known identity were detected in these three phases when compared with Day 0. Of these metabolites, a high level of ß-Alanine indicated a better degree of vascularization and 14 days of in vitro dynamic culture is required to develop a functionalized vascular structure. These results enriched our understanding of the metabolic mechanism of DLS vascularization and indicated that ß-Alanine could function as a potential predictor of the patency of vascularized bioengineered livers.

Building roof extraction from ASTIL echo images applying OSA-YOLOv5s.

Light detection and ranging (LiDAR) is a type of essential tool for urban planning and geoinformation extraction. Airborne streak tube imaging LiDAR (ASTIL) is a new system with great advantages in the rapid collection of remote sensing data. To the best of our knowledge, a new method to extract a building roof from the echo images of ASTIL is proposed. We improve YOLOv5s with a one-shot aggregation (OSA) module to improve efficiency. The experimental results show that the mean average precision of the OSA-YOLOv5s algorithm can reach 95.2%, and the frames per second can reach 11.74 using a CPU and 39.39 using a GPU. The method proposed can extract building objects efficiently from the echo images of ASTIL and acquire the building roof point cloud.

High-pulse-energy passively Q-switched sub-nanosecond MOPA laser system operating at kHz level.

A passively Q-switched sub-nanosecond master oscillator power amplifier (MOPA) laser system at 1064 nm has been reported in this paper. The master oscillator was a passively Q-switched YAG/Nd:YAG/Cr4+:YAG microchip laser, yielding a pulse energy of 0.14 mJ and a pulse width of ∼490 ps at repetition rates of 500 Hz and 1 kHz. After passing a double-pass side-pumped Nd:YAG amplification system, the pulse energy reached 7.6 mJ and 1.7 mJ at 500 Hz and 1 kHz, respectively. The spatial beam deformation caused by the thermally induced birefringence was investigated numerically and experimentally.

Generation and amplification of a multi-beam sub-nanosecond laser.

In this paper, a methodology to produce a multi-beam sub-nanosecond laser is proposed. Laser pulses with a pulse energy of 0.14 mJ and a pulse width of 490 ps are generated in a YAG/Nd:YAG/Cr4+:YAG microchip laser at a repetition rate of 200 Hz. After amplification with a laser diode (LD) side-pumped Nd:YAG module, four laser beams are generated because of the thermally induced birefringence. With a double-pass LD side-pumped amplifier, the single pulse energy of the four laser beams is amplified to 5.23 mJ with a peak power of ∼10.67 MW, and air breakdown with four points is achieved with a 2 × 2 lens array.

GC-MS metabolomics identifies novel biomarkers to distinguish tuberculosis pleural effusion from malignant pleural effusion.

BACKGROUND: Tuberculous pleural effusions (TBPEs) and malignant pleural effusions (MPEs) are two of the most common and severe forms of exudative effusions. Clinical differentiation is challenging; however, metabolomics is a collection of powerful tools currently being used to screen for disease-specific biomarkers. METHODS: 17 TBPE and 17 MPE patients were enrolled according to the inclusion criteria. The normalization gas chromatography-mass spectrometry (GC-MS) data were imported into the SIMCA-P + 14.1 software for multivariate analysis. The principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLS-DA) were used to analyze the data, and the top 50 metabolites of variable importance projection (VIP) were obtained. Metabolites were qualitatively analyzed using the National Institute of Standards and Technology (NIST) databases. Pathway analysis was performed by MetaboAnalyst 4.0. The detection of biochemical indexes such as urea and free fatty acids in these pleural effusions was also verified, and significant differences were found between these two groups. RESULTS: 1319 metabolites were screened by non-targeted metabonomics of GC-MS. 9 small molecules (urea, L-5-oxoproline, L-valine, DL-ornithine, glycine, L-cystine, citric acid, stearic acid, and oleamide) were found to be significantly different (p < 0.05 for all). In OPLS-DA, 9 variables were considered significant for biological interpretation (VIP≥1). However, after the ROC curve was performed, it was found that the metabolites with better diagnostic value were stearic acid, L-cystine, citric acid, free fatty acid, and creatinine (AUC > 0.8), with good sensitivity and specificity. CONCLUSION: Stearic acid, L-cystine, and citric acid may be potential biomarkers, which can be used to distinguish between the TBPE and the MPE.

Device-Free Human Activity Recognition with Low-Resolution Infrared Array Sensor Using Long Short-Term Memory Neural Network.

Sensor-based human activity recognition (HAR) has attracted enormous interests due to its wide applications in the Internet of Things (IoT), smart homes and healthcare. In this paper, a low-resolution infrared array sensor-based HAR approach is proposed using the deep learning framework. The device-free sensing system leverages the infrared array sensor of 8×8 pixels to collect the infrared signals, which can ensure users' privacy and effectively reduce the deployment cost of the network. To reduce the influence of temperature variations, a combination of the J-filter noise reduction method and the Butterworth filter is performed to preprocess the infrared signals. Long short-term memory (LSTM), a representative recurrent neural network, is utilized to automatically extract characteristics from the infrared signal and build the recognition model. In addition, the real-time HAR interface is designed by embedding the LSTM model. Experimental results show that the typical daily activities can be classified with the recognition accuracy of 98.287%. The proposed approach yields a better result compared to the existing machine learning methods, and it provides a low-cost yet promising solution for privacy-preserving scenarios.

Effects of Freeze-Thaw Cycles of Blood Samples on High-Coverage Quantitative Metabolomics.

Blood metabolomics has been widely used for discovering potential metabolite biomarkers of various diseases. In this study, we report our investigation of the effects of freeze-thaw cycles (FTCs) of human serum samples on quantitative metabolomics using a differential chemical isotope labeling (CIL) LC-MS method. A total of 99 serum samples collected from healthy individuals (47 females and 52 males) were subjected to five FTCs, followed by 12C-/13C-dansylation labeling LC-MS analysis. A total of 2790 peak pairs or metabolites were relatively quantified among the 495 comparative samples, including 150 positively identified metabolites, 235 high-confident putatively identified metabolites and 1949 mass-matched metabolites from database searches. Multivariate analysis of the metabolome data showed a clustering of the third to fifth FTC samples in contrast to the separation of the first and second FTC samples, indicating that the extent of FTC-induced metabolome changes became smaller after the third cycle. The changing patterns among the FTC-effected metabolites were found to be complex. Using sex as a biological factor for grouping, we observed a clear separation of males and females when the samples were subjected to the same number of FTCs. However, when the male- and female-samples with different numbers of FTCs were compared, the number of significant metabolites found in male-female comparison increased dramatically, indicating that FTC effects could lead to a large number of false positives in biomarker discovery. Finally, we proposed a method of detecting the FTC effects by reanalyzing the original samples after subjecting them to an additional FTC.

Characterizing the effects of hypoxia on the metabolic profiles of mesenchymal stromal cells derived from three tissue sources using chemical isotope labeling liquid chromatography-mass spectrometry.

Microenvironmental factors such as oxygen concentration mediate key effects on the biology of mesenchymal stromal cells (MSCs). Herein, we performed an in-depth characterization of the metabolic behavior of MSCs derived from the placenta, umbilical cord, and adipose tissue (termed hPMSCs, UC-MSCs, and AD-MSCs, respectively) at physiological (hypoxic; 5% oxygen [O2]) and standardized (normoxic; 21% O2) O2 concentrations using chemical isotope labeling liquid chromatography-mass spectrometry. 12C- and 13C-isotope dansylation (Dns) labeling was used to analyze the amine/phenol submetabolome, and 2574 peak pairs or metabolites were detected and quantified, from which 52 metabolites were positively identified using a library of 275 Dns-metabolite standards; 2189 metabolites were putatively identified. Next, we identified six metabolites using the Dns library, as well as 14 hypoxic biomarkers from the human metabolome database out of 96 altered metabolites. Ultimately, metabolic pathway analyses were performed to evaluate the associated pathways. Based on pathways identified using the Kyoto Encyclopedia of Genes and Genomes, we identified significant changes in the metabolic profiles of MSCs in response to different O2 concentrations. These results collectively suggest that O2 concentration has the strongest influence on hPMSCs metabolic characteristics, and that 5% O2 promotes arginine and proline metabolism in hPMSCs and UC-MSCs but decreases gluconeogenesis (alanine-glucose) rates in hPMSCs and AD-MSCs. These changes indicate that MSCs derived from different sources exhibit distinct metabolic profiles.

Voxel-based spatial elongation filtering method for airborne single-photon LiDAR data.

A novel voxel-based spatial elongation filtering method is proposed, to reduce noise in airborne single-photon lidar (SPL) data. In this method, six additional points are generated adjacent to each point of interest in the SPL data. Then, we count the number of points within each voxel and discriminate signals from noise via a predefined threshold. A filter performance evaluation index (taking into account the false alarm and signal loss rates, and the average distance between the residual noise points and their nearest signal points) is introduced. We compare the proposed and voxel-based spatial filtering method. The average false alarm rate found with our method (3.5%) is 18.6% smaller than that of the voxel-based spatial filtering method (4.3%).

Variation in the gut microbial community is associated with the progression of liver regeneration.

AIM: To highlight a potential dynamic interaction between intestinal bacteria (IB) and metabolites that might contribute to liver regeneration (LR). METHODS: Male Sprague-Dawley rats were subjected to surgical removal of two-thirds of the liver and samples were collected over a 14-day period. Intestinal community and metabolic profiles were characterized to establish their potential interactions during liver regeneration. RESULTS: Partial hepatectomy caused fluctuating changes in the gut microbiome, which paralleled the biological processes of LR. Briefly, the enhanced cell proliferation occurring within 30-48 h was associated with a decreased ratio of Firmicutes to Bacteroidetes reflected by a reduction in Ruminococcaceae and Lachnospiraceae, and an increase in Bacteroidaceae, Rikenellaceae, and Porphyromonadaceae, which was indicative of a lean phenotype. The microbiota derived from rats at 12-24 h and 3-14 days were characterized by elevated F/B ratios, suggesting the differing energy extract behaviors of microbiota during the course of LR. Functional changes of the shifted microbiota revealed by PICRUSt software confirmed the pyrosequencing results. The microbiome derived from hour 12 rats showed overpresentation of metabolism-related modules. In contrast, the microbiome derived from day 2 rats was functionally unique in "replication and repair", "amino acid metabolism," and "nucleoid metabolism." Upon examining the dynamic pattern of metabolic response, the specific pathways, including glycerophospholipid metabolism, taurine, and hypotaurine metabolism, were identified to be attributable to the systemic alterations in LR-related metabolism. Moreover, our data indicated that several key functional bacteria were strongly related to perturbations of the above pathways. CONCLUSION: Gut flora could play a central role in manipulating metabolic responses in LR.

MSC-triggered metabolomic alterations in liver-resident immune cells isolated from CCl4-induced mouse ALI model.

Clinical trials testing mesenchymal stem cell (MSC) as a cellular remedy for acute liver injury (ALI) are underway, but its underlying mechanism has not been thoroughly scrutinized. We highlight that the metabolomic profile of the liver-resident immune cells is significantly altered after MSC administration; its potential correlation with ALI remission is discussed in this study. C57BL/6 mice are randomly divided into three groups: the sham group, MSC-treated ALI group and PBS-treated ALI group; acute liver injury is induced by intraperitoneal injection of carbon tetrachloride. A high-performance chemical isotope labeling liquid chromatography-mass spectrometry (CIL LC-MS) is exploited to profile amine, phenol and carbonyl submetabolome of the liver-resident immune cells in different treatments. 4295 peak pairs are quantified and 2461 peak pairs are further identified in zero-reaction and one-reaction libraries. Clear separation of the three groups is observed in the global PCA and OPLS-DA analyses. We identified 256 metabolites to be candidate biomarkers for ALI-activated immunity and 114 metabolites to be candidate biomarkers for MSC-modulated immunity. Ariginine, aspartate and glutamate metabolism are most affected in both cases, with eight significantly regulated metabolites as joints (glutamic-gamma-semialdehyde, aspartate acid, glutamate acid, gamma-Aminobutyric acidorinithine, 2-keto-glutaramic acid, N-acetylornithine, citrulline and ornithine). These findings shed new light on the therapeutic benefit of immune modulation during ALI rescue. It needs to be further investigated whether exogenous supply of certain metabolites will exert a profound impact on the metabolic network, crosstalking with immune responses and modulating ALI prognosis.

Controlling Preanalytical Process in High-Coverage Quantitative Metabolomics: Spot-Sample Collection for Mouse Urine and Fecal Metabolome Profiling.

Compared to conventional MS and NMR techniques, high-performance chemical isotope labeling (CIL) LC-MS provides accurate relative quantification of many more metabolites in biological samples. However, to apply this technique for urine and fecal metabolomics studies of animal models, the entire workflow, including the preanalytical process, needs to be strictly controlled to avoid or minimize quantitative errors. In this study, we report our investigation of the effects of mouse urine and fecal sample collection methods on CIL LC-MS metabolome analysis. Metabolic-cage collection and spot-sample collection of urine and feces were compared in a mouse model of CCl4-induced liver disease. 13C-/12C-dansylation LC-MS was used for quantitative profiling of the amine-/phenol-submetabolome changes. A total of 5026, 4963, 4238, and 4600 peak pairs or metabolites were detected from spot urine, spot feces, cage-collected urine, and cage-collected feces, respectively. It was found that samples collected using metabolic cages, widely used in low coverage metabolomics, could be contaminated with food as well as cross-specimen (urine in feces or feces in urine) to the extent that metabolomic comparison of different groups of mice could be seriously compromised in high-coverage metabolomics. In contrast, spot urine and spot feces could be collected without contamination and should be used in CIL LC-MS metabolomics.

30 mJ, 1 kHz sub-nanosecond burst-mode Nd:YAG laser MOPA system.

We demonstrated a sub-nanosecond burst-mode MOPA Nd:YAG laser at 1.06 µm that consists of a cavity-dumped Q-switched master oscillator and a double-pass side-pumped amplification system. During the 1 kHz burst-mode operation, outputs with the single pulse energy of 29.8 mJ were obtained within the burst duration of 100 ms. The pulse width was 900 ps, which resulted in a peak power of 33.1 MW. During the 10 Hz operation, the single pulse energy reached 81 mJ with a pulse width of 900 ps, which resulted in a peak power of 90 MW.

Deblurring streak image of streak tube imaging lidar using Wiener deconvolution filter.

We use a Wiener deconvolution filter to deblur the streak image of streak tube imaging lidar to improve the spatial resolution of the system and reduce the edge blurring effect in point clouds. Experiments were performed to investigate the performance of the deconvolution method. Results show that the spatial resolution improved from 9 to 4.5 mm, and the root-mean-square errors of the edge regions are effectively reduced. Additionally, the transition section decreases from 14 to 5.6 mm when the target is 5 m away from the receiver.