Navitoclax safety, tolerability, and effect on biomarkers of senescence and neurodegeneration in aged nonhuman primates.

Alzheimer's disease (AD) is the most common global dementia and is universally fatal. Most late-stage AD disease-modifying therapies are intravenous and target amyloid beta (Aß), with only modest effects on disease progression: there remains a high unmet need for convenient, safe, and effective therapeutics. Senescent cells (SC) and the senescence-associated secretory phenotype (SASP) drive AD pathology and increase with AD severity. Preclinical senolytic studies have shown improvements in neuroinflammation, tau, Aß, and CNS damage; most were conducted in transgenic rodent models with uncertain human translational relevance. In this study, aged cynomolgus monkeys had significant elevation of biomarkers of senescence, SASP, and neurological damage. Intermittent treatment with the senolytic navitoclax induced modest reversible thrombocytopenia; no serious drug-related toxicity was noted. Navitoclax reduced several senescence and SASP biomarkers, with CSF concentrations sufficient for senolysis. Finally, navitoclax reduced TSPO-PET frontal cortex binding and showed trends of improvement in CSF biomarkers of neuroinflammation, neuronal damage, and synaptic dysfunction. Overall, navitoclax administration was safe and well tolerated in aged monkeys, inducing trends of biomarker changes relevant to human neurodegenerative disease.

Design, synthesis and bioevaluation of dual EGFR-PI3Kα inhibitors for potential treatment of NSCLC.

Aberrant activation or mutation of the EGFR-PI3K-Akt-mTOR signaling pathway has been implicated in a wide range of human cancers, especially non-small-cell lung cancer (NSCLC). Thus, dual inhibition of EGFR and PI3K has been investigated as a promising strategy to address acquired drug resistance resulting from the use of tyrosine kinase inhibitors. A series of dual EGFR/PI3Kα inhibitors was synthesized using pharmacophore hybridization of the third-generation EGFR inhibitor olmutinib and the PI3Kα selective inhibitor TAK-117. The optimal compound 30k showed potent kinase inhibitory activities with IC50 values of 3.6 and 30.0 nM against EGFRL858R/T790M and PI3Kα, respectively. Compound 30k exhibited a significant antiproliferative effect in NCI-H1975 cells with a higher selectivity profile than olmutinib. The potential antitumor mechanism, molecular binding modes, and in vitro metabolic stability of compound 30k were also clarified.

Taxonomic characterization and comparative genomic analysis of a novel Devosia species revealed that phenolic acid-degrading traits are ubiquitous in the Devosia genus.

Phenolic acids (PAs) are widely distributed allelochemicals in various environments. To better understand the fate of PAs in environments, a halotolerant PAs-degrading bacterium (named strain RR2S18T) isolated from rhizosphere soil was identified as a novel species of Devosia, named Devosia rhizosphaerae sp. nov. The strain initially degraded PAs into central ring-fission intermediates (protocatechuic acid) using the CoA-dependent non-ß-oxidation pathway. The produced ring-fission intermediates were then consecutively degraded by an ortho-cleavage reaction and the ß-ketoadipic acid pathway. A comparative genomics analysis of 62 Devosia strains revealed that PAs-degrading genes were ubiquitous in their genomes, indicating that PAs degradation is universal among members of this genus. The analysis also suggested that the genes involved in CoA-dependent non-ß-oxidation are inherent to Devosia strains, while those involved in ring-fission and ß-ketoadipic acid pathways were obtained by horizontal gene transfer.

Optimal door-to-balloon time for primary percutaneous coronary intervention for ST-elevation myocardial infarction.

BACKGROUND: Door-to-balloon time (DTBT) for ST-elevation myocardial infarction (STEMI) is a performance metric by which primary percutaneous coronary intervention (PPCI) services are assessed. METHODS: Consecutive patients presenting with STEMI undergoing PPCI between January 2007 to December 2019 from the Singapore Myocardial Infarction Registry were included. Patients were stratified based on DTBT (≤60 min, 61-90 min, 91-180 min) and Killip status (I-III vs. IV). Outcomes assessed included all-cause mortality and major adverse cardiovascular events (MACE) at 30-days and 1-year. RESULTS: In total, 13,823 patients were included, with 82.59% achieving DTBT ≤90 min and 49.77% achieving DTBT ≤60 min. For Killip I-III (n = 11,591,83.85%), the median DTBT was 60[46-78]min. The 30-day all-cause mortality for DTBT of ≤60 min, 61-90 min and 91-180 min was 1.08%, 2.17% and 4.33% respectively (p < 0.001). On multivariate analysis, however, there was no significant difference for 30-day and 1-year outcomes across all DTBT (p > 0.05). For Killip IV, the median DTBT was 68[51-91]min. The 30-day all-cause mortality for DTBT of ≤60 min, 61-90 min and 91-180 min was 11.74%, 20.48% and 35.06% respectively (p < 0.001). On multivariate analysis for 30-day and 1-year outcomes, DTBT 91-180 min was an independent predictor of worse outcomes (p < 0.05), but there was no significant difference between DTBT of ≤60 min and 61-90 min (p > 0.05). CONCLUSION: In Killip I-III patients, DTBT had no significant impact on outcomes upon adjustment for confounders. Conversely, for Killip IV patients, a DTBT of >90 min was associated with significantly higher adverse outcomes, with no differences between a DTBT of ≤60 min vs. 61-90 min. Outcomes in STEMI involve a complex interplay of factors and recommendations of a lowered DTBT of ≤60 min will require further evaluation.

A comprehensive comparative genomic analysis revealed that plant growth promoting traits are ubiquitous in strains of Stenotrophomonas.

Stenotrophomonas strains, which are often described as plant growth promoting (PGP) bacteria, are ubiquitous in many environments. A total of 213 genomes of strains of Stenotrophomonas were analyzed using comparative genomics to better understand the ecological roles of these bacteria in the environment. The pan-genome of the 213 strains of Stenotrophomonas consists of 27,186 gene families, including 710 core gene families, 11,039 unique genes and 15,437 accessory genes. Nearly all strains of Stenotrophomonas harbor the genes for GH3-family cellulose degradation and GH2- and GH31-family hemicellulose hydrolase, as well as intact glycolysis and tricarboxylic acid cycle pathways. These abilities suggest that the strains of this genus can easily obtain carbon and energy from the environment. The Stenotrophomonas strains can respond to oxidative stress by synthesizing catalase, superoxide dismutase, methionine sulfoxide reductase, and disulfide isomerase, as well as managing their osmotic balance by accumulating potassium and synthesizing compatible solutes, such as betaine, trehalose, glutamate, and proline. Each Stenotrophomonas strain also contains many genes for resistance to antibiotics and heavy metals. These genes that mediate stress tolerance increase the ability of Stenotrophomonas strains to survive in extreme environments. In addition, many functional genes related to attachment and plant colonization, growth promotion and biocontrol were identified. In detail, the genes associated with flagellar assembly, motility, chemotaxis and biofilm formation enable the strains of Stenotrophomonas to effectively colonize host plants. The presence of genes for phosphate-solubilization and siderophore production and the polyamine, indole-3-acetic acid, and cytokinin biosynthetic pathways confer the ability to promote plant growth. These strains can produce antimicrobial compounds, chitinases, lipases and proteases. Each Stenotrophomonas genome contained 1-9 prophages and 17-60 genomic islands, and the genes related to antibiotic and heavy metal resistance and the biosynthesis of polyamines, indole-3-acetic acid, and cytokinin may be acquired by horizontal gene transfer. This study demonstrates that strains of Stenotrophomonas are highly adaptable for different environments and have strong potential for use as plant growth-promoting bacteria.

Dual Channel H2O2 Photosynthesis in Pure Water over S-Scheme Heterojunction Cs3PMo12/CC Boosted by Proton and Electron Reservoirs.

Dual channel photo-driven H2O2 production in pure water on small-scale on-site setups is a promising strategy to provide low-concentrated H2O2 whenever needed. This process suffers, however, strongly from the fast recombination of photo-generated charge carriers and the sluggish oxidation process. Here, insoluble Keggin-type cesium phosphomolybdate Cs3PMo12O40 (abbreviated to Cs3PMo12) is introduced to carbonized cellulose (CC) to construct S-scheme heterojunction Cs3PMo12/CC. Dual channel H2O2 photosynthesis from both H2O oxidation and O2 reduction in pure water has been thus achieved with the production rate of 20.1 mmol L-1 gcat. -1 h-1, apparent quantum yield (AQY) of 2.1% and solar-to-chemical conversion (SCC) efficiency of 0.050%. H2O2 accumulative concentration reaches 4.9 mmol L-1. This high photocatalytic activity is guaranteed by unique features of Cs3PMo12/CC, namely, S-scheme heterojunction, electron reservoir, and proton reservoir. The former two enhance the separation of photo-generated charge carriers, while the latter speeds up the torpid oxidation process. In situ experiments reveal that H2O2 is formed via successive single-electron transfer in both channels. In real practice, exposing the reaction system under natural sunlight outdoors successfully results in 0.24 mmol L-1 H2O2. This work provides a key practical strategy for designing photocatalysts in modulating redox half-reactions in photosynthesis.

Use of antiviral drugs and incidence of Parkinson's disease in Taiwan.

Patients infected with herpes zoster might be at risk for Parkinson's disease (PD). However, antiviral drugs may impede viral deoxyribonucleic acid (DNA) synthesis. This study aimed to determine whether the currently observed association between herpes zoster and PD is consistent with previous findings, and whether antiviral drug use is associated with PD. This retrospective cohort study used the Longitudinal Generation Tracking Database. We included patients aged 40 years and above and applied propensity score matching at 1:1 ratio for study comparability. PD risk was evaluated using Cox proportional hazards regression methods. A total of 234,730 people were analyzed. The adjusted hazard ratio (aHR) for PD in patients with herpes zoster was 1.05. Furthermore, the overall incidence of PD was lower in those treated with antiviral drugs than in the untreated ones (3.17 vs. 3.76 per 1,000 person-years); the aHR was 0.84. After stratifying for sex or age, a similar result was observed. In conclusion, herpes zoster may increase the risk of PD, particularly among females, but receiving antiviral treatment reduces the risk by 16%. Therefore, using antiviral drugs may help prevent PD. However, additional research is required to determine the underlying mechanism(s).

Design, Synthesis, Formulation, and Bioevaluation of Trisubstituted Triazines as Highly Selective mTOR Inhibitors for the Treatment of Human Breast Cancer.

The aberrant activation of the PI3K/mTOR signaling pathway is implicated in various human cancers. Thus, the development of inhibitors targeting mTOR has attracted considerable attention. In this study, we used a structure-based drug design strategy to discover a highly potent and kinase-selective mTOR inhibitor 24 (PT-88), which demonstrated an mTOR inhibitory IC50 value of 1.2 nM without obvious inhibition against another 195 kinases from the kinase profiling screening. PT-88 displayed selective inhibition against MCF-7 cells (IC50: 0.74 µM) with high biosafety against normal cells, in which autophagy induced by mTOR inhibition was implicated. After successful encapsulation in a lipodisc formulation, PT-88 demonstrated favorable pharmacokinetic and biosafety profiles and exerted a large antitumor effect in an MCF-7 subcutaneous bearing nude mice model. Our study shows the discovery of a highly selective mTOR inhibitor using a structure-based drug discovery strategy and provides a promising antitumor candidate for future study and development.

Conductive interpenetrating network organohydrogels of gellan gum/polypyrrole with weather-tolerance, piezoresistive sensing and shape-memory capability.

To develop ecofriendly multifunctional gel materials for sustainable flexible electronic devices, composite organohydrogels of gellan gum (GG) and polypyrrole (PPy) with an interpenetrating network structure (IPN-GG/PPy organohydrogels) were developed first time, through fabrication of GG organohydrogels followed by in-situ oxidation polymerization of pyrrole inside. Combination of water with glycerol can not only impart environment-stability to GG hydrogels but promote the mechanics remarkably, with the compressive strength amplified by 1250 % from 0.02 to 0.27 MPa. Incorporation of PPy confers electrical conductivity to the GG organohydrogel as well as promoting the mechanical performance further. The maximum conductivity of the IPN-GG/PPy organohydrogels reached 1.2 mS/cm at 25 °C, and retained at 0.6 mS/cm under -20 °C and 0.56 mS/cm after 7 days' exposure in 25 °C and 60 % RH. The compression strength of that with the maximum conductivity increases by 170 % from 0.27 to 0.73 MPa. The excellent conductivity and mechanical properties endow the IPN-GG/PPy organohydrogels good piezoresistive strain/pressure sensing behavior. Moreover, the thermo-reversible GG network bestows them shape-memory capability. The multifunctionality and intrinsic eco-friendliness is favorable for sustainable application in fields such as flexible electronics, soft robotics and artificial intelligence, competent in motion recognition, physiological signal monitoring, intelligent actuation.

Genomic and transcriptomic analyses provide new insights into the allelochemical degradation preference of a novel Acinetobacter strain.

A novel n-alkane- and phenolic acid-degrading Acinetobacter strain (designated C16S1T) was isolated from rhizosphere soil. The strain was identified as a novel species named Acinetobacter suaedae sp. nov. using a polyphasic taxonomic approach. Strain C16S1T showed preferential degradation of three compounds: p-hydroxybenzoate (PHBA) > ferulic acid (FA) > n-hexadecane. In a medium containing two or three of these allelochemicals, coexisting n-hexadecane and PHBA accelerated each other's degradation and that of FA. FA typically hindered the degradation of n-hexadecane but accelerated PHBA degradation. The upregulated expression of n-hexadecane- and PHBA-degrading genes induced, by their related substrates, was mutually enhanced by coexisting PHBA or n-hexadecane; in contrast, expression of both gene types was reduced by FA. Coexisting PHBA or n-hexadecane enhanced the upregulation of FA-degrading genes induced by FA. The expressions of degrading genes affected by coexisting chemicals coincided with the observed degradation efficiencies. Iron shortage limited the degradation efficiency of all three compounds and changed the degradation preference of Acinetobacter. The present study demonstrated that the biodegradability of the chemicals, the effects of coexisting chemicals on the expression of degrading genes and the strain's growth, the shortage of essential elements, and the toxicity of the chemicals were the four major factors affecting the removal rates of the coexisting allelochemicals.

Halomonas rhizosphaerae sp. nov. and Halomonas kalidii sp. nov., two novel moderate halophilic phenolic acid-degrading species isolated from saline soil.

Four vanillic acid-degrading bacterial strains, named LR5S13T, LR5S20, and M4R5S39T and LN1S58, were isolated from Kalidium cuspidatum rhizosphere and bulk soils, respectively. Phylogenetic analysis based on 16S rRNA gene as well as core genome revealed that LR5S13T and LR5S20 clustered closely with each other and with Halomonas ventosae Al12T, and that the two strains shared the highest similarities (both 99.3 %) with H. ventosae Al12T, in contrast, M4R5S39T and LN1S58 clustered together and with Halomonas heilongjiangensis 9-2T, and the two strains shared the highest similarities (99.4 and 99.2 %, respectively) with H. heilongjiangensis 9-2T. The average nucleotides identities based on BLAST (ANIb) and digital DNA-DNA hybridization (dDDH) values of strains LR5S13T to LR5S20, and M4R5S39T to LN1S58, were both higher than the threshold values for delineation of a species. The ANIb and dDDH values of the four strains to their closely relatives were lower than the threshold values. All four strains take phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol as the major polar lipids, Summed Feature 8, Summed Feature 3, and C16:0 as the major fatty acids. Based on the phylogenetic and phenotypic results, the four strains should be classified as two novel Halomonas species. Therefore, Halomonas rhizosphaerae sp. nov. (type strain LR5S13T = KCTC 8016T = CGMCC 1.62049T) and Halomonas kalidii (type strain M4R5S39T = KCTC 8015T = CGMCC 1.62047T) are proposed. The geographical distribution analysis based on 16S rRNA gene revealed that the two novel species are widely distributed across the globe, specifically in highly saline habits, especially in Central and Eastern Asia.

Establishment of HPLC characteristic chromatogram and quantitative transmission laws for Baqi Rougan Decoction reference sample / 中成药

AIM To establish the HPLC characteristic chromatogram of Baqi Rougan Decoction reference sample,and to investigate its quantitative transmission laws.METHODS The contents of calycosin 7-O-glucoside,hesperidin,rosmarinic acid,curcumenol and nystose were determined.The transfer rates of decoction piece-aqueous decoction-reference sample were calculated,after which the paste-forming rate and pH value were recorded.RESULTS There were sixteen characteristic peaks in fifteen batches of reference samples with the similarities of 0.90,nine of which were identified.The average transfer rates of nystose and calycosin 7-O-glucoside in the reference sample were(83.14±6.25)%and(77.81±8.31)%,while those of rosmarinic acid and curcumenol in the aqueous decoction-reference sample were(81.71±6.27)%and(72.16±5.91)%,along with the average paste-forming rate and pH value of(38.91%±1.46%)and 5.13±0.08,respectively.CONCLUSION This stable and feasible method can provide a reference for the selection of preparation process and evaluation of key chemical properties for Baqi Rougan Decoction.

Effect of CTSS non-synonymous mutations on litter size in Qianbei Ma goats.

Cathepsin S (CTSS) is a member of the cysteine protease family closely related to reproductive regulation in goats. However, its effect on litter size in goats remains unclear. In this study, the relationship between CTSS gene polymorphisms and litter size was revealed by analyzing the DNA sequence and mRNA expression of CTSS in the gonadal axis of Qianbei Ma goats. In addition, bioinformatics methods were used to evaluate the effect of non-synonymous mutations on CTSS protein structure and function. CTSS was expressed in all parts of the gonadal axis of Qianbei Ma goats, with the highest expression in the uterus in the multi-lamb group and in the fallopian tube in the single-lamb group. The sequencing results showed that four SNPs in CTSS, including g.7413C → T, g.8816A → T, g.9191 T → G and g.10193G → A, were significantly correlated with litter size (p < 0.05). All four analyzed mutation sites were in strong linkage disequilibrium (r2 > 0.33, D' > 0.70). Additionally, the haplotype Hap1/2 had a significantly higher frequency than the other haplotypes (p < 0.05). g.7413C → T and g.8816A → T were non-synonymous mutations. The g.7413C → T mutation resulted in the substitution of serine 161 of the CTSS protein with phenylalanine (p.S161F), and the g.8816A → T mutation resulted in the substitution of aspartate 219 with tyrosine (p.N219Y). p.S161F was highly conserved across 13 species and that p.N219Y was relatively conserved in cloven-hoofed species. Mutations at two sites changed the local conformation of the CTSS protein, reduced its stability, and affected its function and goat breed evolution. These findings confirm that CTSS affects the lambing traits of goats and provide a theoretical basis for the regulatory mechanism of CTSS in affecting litter size.

Aquibacillus rhizosphaerae sp. nov., an Indole Acetic Acid (IAA)-producing Halotolerant Bacterium Isolated from the Rhizosphere Soil of Kalidium cuspidatum.

A bacterium (named strain LR5S19T) was isolated from the rhizosphere soil of the halophyte Kalidium cuspidatum in Baotou, Inner Mongolia, China. Strain LR5S19T was Gram-stain-positive, motile with a polar flagellum, rod shaped, and spore forming at the terminal position in swollen sporangia, and it grew at 10-40 ℃ (optimum 30 ℃), pH 6.0-9.0 (optimum pH 7.0), and in the presence of 1.0-15.0% (w/v) NaCl (optimum 2.0%). The phylogenetic analysis of the 16S rRNA gene showed that strain LR5S19T shared the highest similarity (96.7%) with A. koreensis JCM 12387T, followed by A. kalidii HU2P27T (96.2%), A. sediminis BH258T (96.1%), and 'A. salsiterrae' 3ASR75-54T (96.0%). The ANIb, AAI and dDDH values between strain LR5S19T and its closely related type strains were 69.3-73.8%, 65.4-72.4% and 19.2-20.3%, respectively. The major polar lipids in strain LR5S19T consisted of diphosphatidylglycerol, phosphatidylglycerol, and three unidentified phospholipids, while MK-7 was the major respiratory quinone. The major fatty acids of the strain were anteiso-C15:0 and iso-C15:0. Based on phylogenomic and phenotypic results, strain LR5S19T should be classified as a novel species within the genus Aquibacillus, for which Aquibacillus rhizosphaerae sp. nov. is proposed. The type strain is LR5S19T (= CGMCC 1.62028T = KCTC 43434T). The comparative genomic analysis revealed that all eight members of Aquibacillus could utilize D-glucose via the glycolysis-gluconeogenesis pathway or the pentose phosphate pathway and use the tricarboxylic acid cycle as the metabolic center. The potassium ion transport proteins and compatible solute synthesis pathways in all the members likely also help them cope with hypersaline environments.

Design, synthesis and bioevaluation of PI3Kα-selective inhibitors as potential colorectal cancer drugs.

The dysregulation of the phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin signaling pathway has been implicated in various human cancers, and isoform-selective inhibitors targeting PI3Kα have received significant interest in recent years. In this study, we have designed and synthesized three series of substituted benzoxazole derivatives based on the clinical candidate TAK-117 (8a). A detailed structure-activity relationship (SAR) study has identified the optimal compound 18a bearing a quinoxaline scaffold. Compared to the control 8a, 18a exhibited 4.4-fold more potent inhibitory activity against PI3Kα (IC50: 2.5 vs 11 nM) and better isoform-selective profiles over other PI3Ks. In addition, 18a showed a 1.5-fold more potent antiproliferative effect against HCT-116 cell lines (IC50: 3.79 vs 5.80 µM) and a better selectivity over the normal tissue cells. The potential antitumor mechanism and in vitro metabolic stability of 18a were also investigated. Notably, pharmacokinetic assays indicated that 18a had a higher plasma exposure, a higher maximum concentration and shorter elimination time compared to 8a.

Virtual screening of novel mTOR inhibitors for the potential treatment of human colorectal cancer.

The abnormal activation of the mTOR pathway is closely related to the occurrence and progression of cancer, especially colorectal cancer. In this study, a rational virtual screening strategy has been established and MT-5, a novel mTOR inhibitor with a quinoline scaffold, was obtained from the ChemDiv database. MT-5 showed potent kinase inhibitory activity (IC50: 8.90 µM) and antiproliferative effects against various cancer cell lines, especially HCT-116 cells (IC50: 4.61 µM), and this was 2.2-fold more potent than that of the cisplatin control (IC50: 9.99 µM). Western blot, cell migration, cycle arrest, and apoptosis assays were performed with HCT-116 cells to investigate the potential anticancer mechanism of MT-5. Metabolic stability results in vitro indicated that MT-5 exhibited good stability profiles in artificial gastrointestinal fluids, rat plasma, and liver microsomes. In addition, the key contribution of the residues around the binding pocket of MT-5 in binding to the mTOR protein was also investigated from a computational perspective.

Residents' Report of COVID-19 Associated Training Disruptions, Stressors, and Opportunities During the Pandemic-The Singapore Experience.

Background: The COVID-19 pandemic has disrupted residency training. Several studies have been performed to investigate the impact of the pandemic on residency training in Accreditation Council for Graduate Medical Education-International (ACGME-I)-accredited institutions. However, these were either limited to certain specialties or failed to consider possible opportunities from the pandemic. Objective: To determine the stressors on residents as well as the opportunities that arose from the COVID-19 pandemic across multiple specialities in Singapore. Methods: A cross-sectional survey among SingHealth residents was conducted between July and September 2020. The survey assessed the balance between service and training during hospital postings, the pandemic's influence on examination and teaching, the psychological impact of the pandemic, the level of burnout, and the effect on morale of residents during the pandemic. Results: The response rate was 27.1% (253 of 934). Out of the 253 residents, 136 (53.8%) felt stressed during the pandemic. Concerns about family's health and safety pertaining to potential COVID-19 infection, progression in training, and completion of examinations were the top 3 stressors. One-hundred and three residents (40.7%) had their training disrupted either by being placed in an interim posting not part of their residency requirements or being deployed to care for patients with COVID-19. Although administrative support and information for virtual teaching were sufficient, only 108 (42.7%) agreed it had the same value as face-to-face sessions. Despite the challenges, 179 (70.8%) thought that experiencing this crisis provided more meaning in their career. Conclusions: The COVID-19 pandemic has brought about challenges and learning opportunities for residents.