Characterization and application of in situ curcumin/ZNP hydrogels for periodontitis treatment.

BACKGROUND: Periodontitis is a chronic inflammatory disease that occurs in tooth-supporting tissues. Controlling inflammation and alleviating periodontal tissue destruction are key factors in periodontal therapy. This study aimed to develop an in situ curcumin/zinc oxide (Cur/ZNP) hydrogel and investigate its characteristics and effectiveness in the treatment of periodontitis. METHODS: Antibacterial activity and cytotoxicity assays were performed in vitro. To evaluate the effect of the in situ Cur/ZNP hydrogel on periodontitis in vivo, an experimental periodontitis model was established in Sprague‒Dawley rats via silk ligature and inoculation of the maxillary first molar with Porphyromonas gingivalis. After one month of in situ treatment with the hydrogel, we examined the transcriptional responses of the gingiva to the Cur/ZNP hydrogel treatment and detected the alveolar bone level as well as the expression of osteocalcin (OCN) and osteoprotegerin (OPG) in the periodontal tissues of the rats. RESULTS: Cur/ZNPs had synergistic inhibitory effects on P. gingivalis and good biocompatibility. RNA sequencing of the gingiva showed that immune effector process-related genes were significantly induced by experimental periodontitis. Carcinoembryonic antigen-related cell adhesion molecule 1 (Ceacam1), which is involved in the negative regulation of bone resorption, was differentially regulated by the Cur/ZNP hydrogel but not by the Cur hydrogel or ZNP hydrogel. The Cur/ZNP hydrogel also had a stronger protective effect on alveolar bone resorption than both the Cur hydrogel and the ZNP hydrogel. CONCLUSION: The Cur/ZNP hydrogel effectively inhibited periodontal pathogenic bacteria and alleviated alveolar bone destruction while exhibiting favorable biocompatibility.

Candida albicans CHK1 gene from two-component system is essential for its pathogenicity in oral candidiasis.

The roles of Candida albicans CHK1, a key gene from two-component system, in oral mucosal infection are not clear. This study evaluated the key roles of CHK1 gene in vitro and in vivo. The expression of CHK1 and its regulated virulence factors were tested during the oral epithelial cell infection. The production of lactate dehydrogenase, ROS, and IL-1α combined with the confocal and scanning electron microscope observation was employed to identify the capability of CHK1 in damaging the epithelial cells. Both immunocompetent and immunodeficient mice oropharyngeal infection models were involved to confirm the roles of CHK1 gene in vivo. The expression of CHK1 gene was significantly increased during the oral epithelial cell infection. The chk1Δ/Δ mutant failed to damage the epithelial cells or induce IL-α and ROS production. Interestingly, chk1Δ/Δ can also form the similar hyphae with WT and complementary strains. Accordingly, chk1Δ/Δ did not affect the adhesion and invasion rates of C. albicans to oral epithelial cells. However, chk1Δ/Δ significantly decreased the expression levels of the virulence factors, including ALS2, SAP6, and YWP1. The chk1Δ/Δ also failed to cause oral candidiasis in both immunocompetent and immunodeficient mice indicating that CHK1 gene from the two-component system is essential for the pathogenicity of C. albicans. KEY POINTS: • CHK1gene is essential for C. albicans in oral candidiasis • C. albicans without CHK1 gene can form "non-pathogenic" hyphae. • CHK1 gene regulates the virulence of C. albicans.

Optimising epilepsy management with a smartphone application: a randomised controlled trial.

OBJECTIVE: To assess whether a practical intervention based upon a smartphone application (app) would improve self-management and seizure control in adults with epilepsy. DESIGN, SETTING: Randomised, controlled trial in western China, December 2017 to August 2018. PARTICIPANTS: 380 eligible people with epilepsy were recruited; 327 completed the 6-month follow-up (176 in the app group, 151 in the control group). MAIN OUTCOME MEASURES: Self-management of epilepsy (measured with the validated Chinese Epilepsy Self-Management Scale, C-ESMS) and self-reported seizure frequency. RESULTS: In the intention-to-treat analysis, the mean C-ESMS score increased significantly in the app group between baseline and the 6-month evaluation (from 121.7 [SD, 12.1] to 144.4 [SD, 10.0]; P < 0.001); improvements on the information management, medication management, and safety management subscales were also statistically significant. At 6 months, the mean overall C-ESMS score for the app group was significantly higher than that for the control group (125.4 [SD, 1.5];  P < 0.001). The proportion of patients who were seizure-free at the 6-month follow-up was larger for the app than the control group (54 of 190, 28% v 22 of 190, 12%), as was the proportion with reductions in frequency of between 75 and 100% (22 of 190, 12% v 8 of 190, 4%). Changes in C-ESMS score were not statistically associated with seizure frequency. CONCLUSIONS: Using a smartphone app improved epilepsy self-management scores in people in western China. It should be further tested in larger populations in other areas. Our preliminary investigation of building digital communities for people with epilepsy should encourage similar approaches to managing other chronic diseases. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR1900026864, 24 October 2019.

Epilepsy management during epidemic: A preliminary observation from western China.

OBJECTIVE: This study aimed to investigate whether the proposed model could manage patients with epilepsy (PWEs) during the coronavirus disease 2019 (COVID-19) outbreak. METHODS: We used a model to manage the PWEs during the outbreak. Questionnaire survey and hospital data were used to explore whether PWEs under our management were affected by the virus. RESULTS: A total of 118 (78.7%) PWEs completed the survey. During the "model period," 22.9% (27/118) of the respondents reported antiepileptic drug (AEDs) discontinuity, including six (22.2%) PWEs who failed to purchase AEDs. Of the patients, 40.7% (22/54) failed to attend ordinary clinic, which was higher than that during the "period before model" (7.9%, 5/63). The common causes were movement limits (77.3%) and appointment failure (54.5%). A shift from ordinary clinic toward remote consultation was observed. Of the PWEs, 15.7% (13/83) referred to online pharmacy. 87.5% (14/16) of emergencies related to epilepsy were timely treated. 48.3%of PWEs thought that the epidemic had an impact on accessing medical services. Hospital data indicated that a decline in ordinary clinic visit, inpatient, surgery, and emergency attendance was observed in January and February 2020 and an increase in March 2020, as the epidemic mitigated. By contrast, online clinic visit soared in February, when the outbreak hit hard. In addition, we found no cross-infection of COVID-19 in our hospital and respondents. CONCLUSION: We demonstrated a much-needed model to manage the PWEs during the outbreak. We believed that the core architecture of this model was suitable for the management of other chronic diseases.

PhySpeTree: an automated pipeline for reconstructing phylogenetic species trees.

BACKGROUND: Phylogenetic species trees are widely used in inferring evolutionary relationships. Existing software and algorithms mainly focus on phylogenetic inference. However, less attention has been paid to intermediate steps, such as processing extremely large sequences and preparing configure files to connect multiple software. When the species number is large, the intermediate steps become a bottleneck that may seriously affect the efficiency of tree building. RESULTS: Here, we present an easy-to-use pipeline named PhySpeTree to facilitate the reconstruction of species trees across bacterial, archaeal, and eukaryotic organisms. Users need only to input the abbreviations of species names; PhySpeTree prepares complex configure files for different software, then automatically downloads genomic data, cleans sequences, and builds trees. PhySpeTree allows users to perform critical steps such as sequence alignment and tree construction by adjusting advanced options. PhySpeTree provides two parallel pipelines based on concatenated highly conserved proteins and small subunit ribosomal RNA sequences, respectively. Accessory modules, such as those for inserting new species, generating visualization configurations, and combining trees, are distributed along with PhySpeTree. CONCLUSIONS: Together with accessory modules, PhySpeTree significantly simplifies tree reconstruction. PhySpeTree is implemented in Python running on modern operating systems (Linux, macOS, and Windows). The source code is freely available with detailed documentation (https://github.com/yangfangs/physpetools).

BAH1 an E3 Ligase from Arabidopsis thaliana Stabilizes Heat Shock Factor σ32 of Escherichia coli by Interacting with DnaK/DnaJ Chaperone Team.

In Escherichia coli, the DnaK/DnaJ chaperone can control the stability and activity of σ32, which is the key factor in heat shock response. Heterologous expression of eukaryotic molecular chaperones protects E. coli from heat stress. Here, we show that BAH1, an E3 ligase from plant that has a similar zinc finger domain to DnaJ, can perform block the effect of DnaK on σ32 in Escherichia coli. By constructing a chimeric DnaJ protein, with the J-domain of DnaJ fused to BAH1, we found BAH1 could partially compensate for the DnaJ' zinc finger domain in vivo, and that it was dependent on the zinc finger domain of BAH1. Furthermore, BAH1 could interact with both σ32 and DnaK to increase the level of HSPs, such as GroEL, DnaK, and σ32. These results suggested that the zinc finger domain was conserved during evolution.

B-Myb Mediates Proliferation and Migration of Non-Small-Cell Lung Cancer via Suppressing IGFBP3.

B-Myb has been shown to play an important oncogenic role in several types of human cancers, including non-small-cell lung cancer (NSCLC). We previously found that B-Myb is aberrantly upregulated in NSCLC, and overexpression of B-Myb can significantly promote NSCLC cell growth and motility. In the present study, we have further investigated the therapeutic potential of B-Myb in NSCLC. Kaplan⁻Meier and Cox proportional hazards analysis indicated that high expression of B-Myb is significantly associated with poor prognosis in NSCLC patients. A loss-of-function study demonstrated that depletion of B-Myb resulted in significant inhibition of cell growth and delayed cell cycle progression in NSCLC cells. Notably, B-Myb depletion also decreased NSCLC cell migration and invasion ability as well as colony-forming ability. Moreover, an in vivo study demonstrated that B-Myb depletion caused significant inhibition of tumor growth in a NSCLC xenograft nude mouse model. A molecular mechanistic study by RNA-seq analysis revealed that B-Myb depletion led to deregulation of various downstream genes, including insulin-like growth factor binding protein 3 (IGFBP3). Overexpression of IGFBP3 suppressed the B-Myb-induced proliferation and migration, whereas knockdown of IGFBP3 significantly rescued the inhibited cell proliferation and motility caused by B-Myb siRNA (small interfering RNA). Expression and luciferase reporter assays revealed that B-Myb could directly suppress the expression of IGFBP3. Taken together, our results suggest that B-Myb functions as a tumor-promoting gene via suppressing IGFBP3 and could serve as a novel therapeutic target in NSCLC.

Phylogenetic Profiling of Mitochondrial Proteins and Integration Analysis of Bacterial Transcription Units Suggest Evolution of F1Fo ATP Synthase from Multiple Modules.

ATP synthase is a complex universal enzyme responsible for ATP synthesis across all kingdoms of life. The F-type ATP synthase has been suggested to have evolved from two functionally independent, catalytic (F1) and membrane bound (Fo), ancestral modules. While the modular evolution of the synthase is supported by studies indicating independent assembly of the two subunits, the presence of intermediate assembly products suggests a more complex evolutionary process. We analyzed the phylogenetic profiles of the human mitochondrial proteins and bacterial transcription units to gain additional insight into the evolution of the F-type ATP synthase complex. In this study, we report the presence of intermediary modules based on the phylogenetic profiles of the human mitochondrial proteins. The two main intermediary modules comprise the α3ß3 hexamer in the F1 and the c-subunit ring in the Fo. A comprehensive analysis of bacterial transcription units of F1Fo ATP synthase revealed that while a long and constant order of F1Fo ATP synthase genes exists in a majority of bacterial genomes, highly conserved combinations of separate transcription units are present among certain bacterial classes and phyla. Based on our findings, we propose a model that includes the involvement of multiple modules in the evolution of F1Fo ATP synthase. The central and peripheral stalk subunits provide a link for the integration of the F1/Fo modules.

An E3 ubiquitin ligase from Brassica napus induces a typical heat-shock response in its own way in Escherichia coli.

Previously, we have identified a novel E3 ubiquitin ligase, BNTR1, which plays a key role in heat stress response in Brassica napus. In this study, we accidentally found that BNTR1 can also improve thermal tolerance and reduce growth inhibition at 42°C in Escherichia coli, in a manner different from that in plant. We show that BNTR1 activates E. coli heat-shock response at low concentration in soluble form instead of in inclusion body, but BNTR1 is not functioning as a heat-shock protein (HSP) because deficient temperature-sensitive mutants of HSP genes display unconspicuous thermal tolerance in the presence of BNTR1. Our further studies show that BNTR1 triggers heat-shock response by competing with σ32 (σ32, heat-shock transcription factor) to its binding proteins DnaJ (HSP40) and DnaK (HSP70), which results in the release and accumulation of σ32, thereby promoting the heat-shock response, even under the non-heat-shock conditions. At 37°C, accumulation of the HSPs induced by BNTR1 could make cells much more tolerant than those without BNTR1 at 42°C. Thus, our results suggest that BNTR1 may potentially be a promising target in fermentation industry for reducing impact from temperature fluctuation, where E. coli works as bioreactors.

The PRR11-SKA2 Bidirectional Transcription Unit Is Negatively Regulated by p53 through NF-Y in Lung Cancer Cells.

We previously identified proline-rich protein 11 (PRR11) as a novel cancer-related gene that is implicated in the regulation of cell cycle and tumorigenesis. Our recent study demonstrated that PRR11 and its adjacent gene, kinetochore associated 2 (SKA2), constitute a classic head-to-head gene pair that is coordinately regulated by nuclear factor Y (NF-Y). In the present study, we further show that the PRR11-SKA2 bidirectional transcription unit is an indirect target of the tumor suppressor p53. A luciferase reporter assay revealed that overexpression of wild type p53, but not mutant p53, significantly represses the basal activity and NF-Y mediated transactivation of the PRR11-SKA2 bidirectional promoter. Deletion and mutation analysis of the PRR11-SKA2 promoter revealed that p53-mediated PRR11-SKA2 repression is dependent on the presence of functional NF-Y binding sites. Furthermore, a co-immunoprecipitation assay revealed that p53 associates with NF-Y in lung cancer cells, and a chromatin immunoprecipitation assay showed that p53 represses PRR11-SKA2 transcription by reducing the binding amount of NF-Y in the PRR11-SKA2 promoter region. Consistently, the ability of p53 to downregulate PRR11-SKA2 transcription was significantly attenuated upon siRNA-mediated depletion of nuclear factor Y subunit beta (NF-YB). Notably, lung cancer patients with lower expression of either PRR11 or SKA2 along with wild type p53 exhibited the best overall survival compared with others with p53 mutation and/or higher expression of either PRR11 or SKA2. Taken together, our results demonstrate that p53 negatively regulates the expression of the PRR11-SKA2 bidirectional transcription unit through NF-Y, suggesting that the inability to repress the PRR11-SKA2 bidirectional transcription unit after loss of p53 might contribute to tumorigenesis.

B-Myb Is Up-Regulated and Promotes Cell Growth and Motility in Non-Small Cell Lung Cancer.

B-Myb is a transcription factor that is overexpressed and plays an oncogenic role in several types of human cancers. However, its potential implication in lung cancer remains elusive. In the present study, we have for the first time investigated the expression profile of B-Myb and its functional impact in lung cancer. Expression analysis by quantificational real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry demonstrated that B-Myb expression is aberrantly overexpressed in non-small cell lung cancer (NSCLC), and positively correlated with pathologic grade and clinical stage of NSCLC. A gain-of-function study revealed that overexpression of B-Myb significantly increases lung cancer cell growth, colony formation, migration, and invasion. Conversely, a loss-of-function study showed that knockdown of B-Myb decreases cell growth, migration, and invasion. B-Myb overexpression also promoted tumor growth in vivo in a NSCLC xenograft nude mouse model. A molecular mechanistic study by RNA-sequencing (RNA-seq) analysis showed that B-Myb overexpression causes up-regulation of various downstream genes (e.g., COL11A1, COL6A1, FN1, MMP2, NID1, FLT4, INSR, and CCNA1) and activation of multiple critical pathways (e.g., extracellular signal-regulated kinases (ERK) and phosphorylated-protein kinase B (Akt) signaling pathways) involved in cell proliferation, tumorigenesis, and metastasis. Collectively, our results indicate a tumor-promoting role for B-Myb in NSCLC and thus imply its potential as a target for the diagnosis and/or treatment of NSCLC.

The gene pair PRR11 and SKA2 shares a NF-Y-regulated bidirectional promoter and contributes to lung cancer development.

Head-to-head gene pairs represent a unique feature of gene organization in eukaryotes, accounting for >10% of genes in the human genome. Identification and functional analysis of such gene pairs is only in its infancy. Recently, we identified PRR11 as a novel cancer-related gene that is implicated in cell cycle and lung cancer. Here we demonstrate that PRR11 is oriented in a head-to-head configuration with its neighboring gene, SKA2. 5'-RACE assay revealed that the intergenic spacer region between the two genes is <500 bp. Serial luciferase reporter assays demonstrated that a minimal 80-bp intergenic region functions as a core bidirectional promoter to drive basal transcription in both the PRR11 and SKA2 orientations. EMSA and ChIP assays demonstrated that NF-Y binds to and directly transactivates the PRR11-SKA2 bidirectional promoter. SiRNA-mediated NF-Y depletion significantly downregulated PRR11 and SKA2 expression. Expression of both PRR11 and SKA2 was significantly upregulated in lung cancer. Expression of the two genes was highly correlated with each other and with NF-Y expression. Remarkably, high expression of both PRR11 and SKA2 was associated with poorer prognosis in lung cancer patients compared with high expression of one gene or low expression of both genes. Knockdown of PRR11 and/or SKA2 remarkably reduced cell proliferation, migration, and invasion in lung cancer cells. Thus, the PRR11-SKA2 bidirectional transcription unit, which is a novel direct target of NF-Y, is essential for the accelerated proliferation and motility of lung cancer cells and may represent a potential target in the diagnosis and/or treatment of human lung cancer.

Analysis of pupylation of Streptomyces hygroscopicus 5008 in vitro.

Prokaryotic ubiquitin-like protein (Pup) is a post-translational modifier that can be attached to substrate proteins in Actinobacteria. The modification process is defined as pupylation and is associated with proteasome-mediated protein degradation in mycobacteria and streptomycetes. Here, we report the pupylation of Streptomyces hygroscopicus 5008 in vitro. Each component of the Pup system was expressed in Escherichia coli and poly-Pup chains were observed by western blot analysis. Though only one potential Pup substrate (SHJG_3659) was identified using MS/MS, we verified this candidate and other predicted substrates by a reconstituted Pup system in E. coli. In addition, we discuss the depupylation activity of Dop (a Pup activation enzyme). The results presented here show that pupylation exists in S. hygroscopicus and that a reconstituted Pup system can function in vitro in a heterologous host.

Cell cycle control, DNA damage repair, and apoptosis-related pathways control pre-ameloblasts differentiation during tooth development.

BACKGROUND: Ameloblast differentiation is the most critical stepwise process in amelogenesis, and it is controlled by precise molecular events. To better understand the mechanism controlling pre-ameloblasts (PABs) differentiation into secretory ameloblasts (SABs), a more precise identification of molecules and signaling networks will elucidate the mechanisms governing enamel formation and lay a foundation for enamel regeneration. RESULTS: We analyzed transcriptional profiles of human PABs and SABs. From a total of 28,869 analyzed transcripts, we identified 923 differentially expressed genes (DEGs) with p < 0.05 and Fold-change > 2. Among the DEGs, 647 genes showed elevated expression in PABs compared to SABs. Notably, 38 DEGs displayed greater than eight-fold changes. Comparative analysis revealed that highly expressed genes in PABs were involved in cell cycle control, DNA damage repair and apoptosis, while highly expressed genes in SABs were related to cell adhesion and extracellular matrix. Moreover, coexpression network analysis uncovered two highly conserved sub-networks contributing to differentiation, containing transcription regulators (RUNX2, ETV1 and ETV5), solute carrier family members (SLC15A1 and SLC7A11), enamel matrix protein (MMP20), and a polymodal excitatory ion channel (TRPA1). CONCLUSIONS: By combining comparative analysis and coexpression networks, this study provides novel biomarkers and research targets for ameloblast differentiation and the potential for their application in enamel regeneration.

Heat shock transcription factor δ³² is targeted for degradation via an ubiquitin-like protein ThiS in Escherichia coli.

The posttranslational modification of proteins with ubiquitin and ubiquitin-like proteins (UBLs) plays an important role in eukaryote biology, through which substrate proteins are targeted for degradation by the proteasome. Prokaryotes have been thought to degrade proteins by an ubiquitin independent pathway. Here, we show that ThiS, an ubiquitin-like protein, is covalently attached to δ(32) and at least 27 other proteins, leading to their subsequent degradation by proteases, in a similar manner to the ubiquitin-proteasome system (UPS) in eukaryotes. Molecular biology and biochemical studies confirm that specific lysine sites in δ(32) can be modified by ThiS. The results presented here establish a new model for δ(32) degradation and show that Escherichia coli uses a small-protein modifier to control protein stability.

Gene expression profiling analysis reveals that DLG3 is down-regulated in glioblastoma.

Glioblastoma multiforme (GBM) is the most malignant glioma. In the current study, 149 astrocytoma gene expression datasets were classified by prediction analysis of microarray. Strikingly, disks large homolog 3 (DLG3), a membrane-associated guanylate kinase-family gene, had the highest score in the GBM subset. DLG3 mRNA expression is significantly down-regulated in GBM relative to normal tissue and grade II or grade III astrocytoma according to the results of real-time polymerase chain reaction, and its protein expression shows an obvious difference by immunohistochemistry. Further assays show that DLG3 over-expression induces mitotic cell cycle arrest and apoptosis, and it inhibits proliferation and migration. However, DLG3 over-expression has almost no affect on invasion. The DLG3 protein expression in human brain GBM tissue and its effects on GBM cell invasion were not expected. Our data suggest that DLG3 is down-regulated in this cancer type. To our knowledge, this is the first report to clearly demonstrate the possible involvement of DLG3 in GBM.

Hyperosmotic response of streptococcus mutans: from microscopic physiology to transcriptomic profile.

BACKGROUND: Oral streptococci metabolize carbohydrate to produce organic acids, which not only decrease the environmental pH, but also increase osmolality of dental plaque fluid due to tooth demineralization and consequent calcium and phosphate accumulation. Despite these unfavorable environmental changes, the bacteria continue to thrive. The aim of this study was to obtain a global view on strategies taken by Streptococcus mutans to deal with physiologically relevant elevated osmolality, and perseveres within a cariogenic dental plaque. RESULTS: We investigated phenotypic change of S. mutans biofilm upon hyperosmotic challenge. We found that the hyperosmotic condition was able to initiate S. mutans biofilm dispersal by reducing both microbial content and extracellular polysaccharides matrix. We then used whole-genome microarray with quantitative RT-PCR validation to systemically investigate the underlying molecular machineries of this bacterium in response to the hyperosmotic stimuli. Among those identified 40 deferentially regulated genes, down-regulation of gtfB and comC were believed to be responsible for the observed biofilm dispersal. Further analysis of microarray data showed significant up-regulation of genes and pathways involved in carbohydrate metabolism. Specific genes involved in heat shock response and acid tolerance were also upregulated, indicating potential cross-talk between hyperosmotic and other environmental stress. CONCLUSIONS: Hyperosmotic condition induces significant stress response on S. mutans at both phenotypic and transcriptomic levels. In the meantime, it may take full advantage of these environmental stimuli to better fit the fluctuating environments within oral cavity, and thus emerges as numeric-predominant bacterium under cariogenic conditions.

Effects of multiple key factors on the performance of petroleum coke-based constructed wetland-microbial fuel cell.

In this study, two constructed wetland-microbial fuel cells (CW-MFC), including a closed-circuit system (CCW-MFC) and an open-circuit system (OCW-MFC) with petroleum coke as electrode and substrate, were constructed to explore the effect of multiple key factors on their operation performances. Compared to a traditional CW, the CCW-MFC system showed better performance, achieving an average removal efficiency of COD, NH4+-N, and TN of 94.49 ± 1.81%, 94.99 ± 4.81%, and 84.67 ± 5.6%, respectively, when the aeration rate, COD concentration, and hydraulic retention time were 0.4 L/min, 300 mg/L, and 3 days. The maximum output voltage (425.2 mV) of the CCW-MFC system was achieved when the aeration rate was 0.2 L/min. In addition, the CCW-MFC system showed a greater denitrification ability due to the higher abundance of Thiothrix that might attract other denitrifying bacteria, such as Methylotenera and Hyphomicrobium, to participate in the denitrifying process, indicating the quorum sensing could be stimulated within the denitrifying microbial community.

Histone deacetylase inhibitor pracinostat suppresses colorectal cancer by inducing CDK5-Drp1 signaling-mediated peripheral mitofission.

Divisions at the periphery and midzone of mitochondria are two fission signatures that determine the fate of mitochondria and cells. Pharmacological induction of excessively asymmetric mitofission-associated cell death (MFAD) by switching the scission position from the mitochondrial midzone to the periphery represents a promising strategy for anticancer therapy. By screening a series of pan-inhibitors, we identified pracinostat, a pan-histone deacetylase (HDAC) inhibitor, as a novel MFAD inducer, that exhibited a significant anticancer effect on colorectal cancer (CRC) in vivo and in vitro. Pracinostat increased the expression of cyclin-dependent kinase 5 (CDK5) and induced its acetylation at residue lysine 33, accelerating the formation of complex CDK5/CDK5 regulatory subunit 1 and dynamin-related protein 1 (Drp1)-mediated mitochondrial peripheral fission. CRC cells with high level of CDK5 (CDK5-high) displayed midzone mitochondrial division that was associated with oncogenic phenotype, but treatment with pracinostat led to a lethal increase in the already-elevated level of CDK5 in the CRC cells. Mechanistically, pracinostat switched the scission position from the mitochondrial midzone to the periphery by improving the binding of Drp1 from mitochondrial fission factor (MFF) to mitochondrial fission 1 protein (FIS1). Thus, our results revealed the anticancer mechanism of HDACi pracinostat in CRC via activating CDK5-Drp1 signaling to cause selective MFAD of those CDK5-high tumor cells, which implicates a new paradigm to develop potential therapeutic strategies for CRC treatment.

Effect of Leaching Behavior on the Geometric and Hydraulic Characteristics of Concrete Fracture.

The leaching of material from concrete fracture surfaces has an impact on the structural concrete in service, but the number of studies that consider the effect of the coupling of the leaching, fracture geometry and hydraulic processes on concrete fractures is insufficient. In this study, a series of experiments was conducted, and a leaching model proposed, to investigate the mechanism of leaching behavior on the geometric and hydraulic characteristics of concrete fractures. Following the leaching experiment, the evolution of fracture geometric characteristics was observed by a three-dimensional (3D) laser scanning technique, finding that the fracture produces residual leached depth and local uneven leaching, which results in a decrease in roughness. The hydraulic characteristics were then investigated by permeability tests, and it was found that the fracture hydraulic aperture and permeability increase monotonically with leaching time. A simulation of fluid flow in a numerical fracture revealed the effect of residual leached depth and a decrease in roughness on the hydraulic characteristics. Finally, based on the analysis of the chemical composition of the leaching solution, a leaching model of concrete rough fracture surface is proposed and the mechanism of leaching behavior is discussed. These new findings are useful for the understanding of the development of leaching, local to concrete fracture surfaces.