Bioactive atropisomers: Unraveling design strategies and synthetic routes for drug discovery

Atropisomerism, an expression of axial chirality caused by limited bond rotation, is a prominent aspect within the field of medicinal chemistry. It has been shown that atropisomers of a wide range of compounds, including established FDA-approved drugs and experimental molecules, display markedly different biological activities. The time-dependent reversal of chirality in atropisomers poses complexity and obstacles in the process of drug discovery and development. Nonetheless, recent progress in understanding atropisomerism and enhanced characterization methods have greatly assisted medicinal chemists in the effective development of atropisomeric drug molecules. This article provides a comprehensive review of their special design thoughts, synthetic routes, and biological activities, serving as a reference for the synthesis and biological evaluation of bioactive atropisomers in the future.

Catalytic Atroposelective Synthesis of Axially Chiral Azomethine Imines and Neuroprotective Activity Evaluation

Azomethine imines, as a prominent class of 1,3-dipolar species, hold great significance and potential in organic and medicinal chemistry. However, the reported synthesis of centrally chiral azomethine imines relies on kinetic resolution, and the construction of axially chiral azomethine imines remains unexplored. Herein, we present the synthesis of axially chiral azomethine imines through copper- or chiral phosphoric acid catalyzed ring-closure reactions of N'-(2-alkynylbenzylidene)hydrazides, showcasing high efficiency, mild conditions, broad substrate scope, and excellent enantioselectivity. Furthermore, the biological evaluation revealed that the synthesized axially chiral azomethine imines effectively protect dorsal root ganglia (DRG) neurons by inhibiting apoptosis induced by oxaliplatin, offering a promising therapeutic approach for chemotherapy-induced peripheral neuropathy (CIPN). Remarkably, the (S)- and (R)-atropisomers displayed distinct neuroprotective activities, underscoring the significance of axial stereochemistry.

Canadine inhibits epithelial mesenchymal transformation of HPV-negative cervical cancer

Although the majority of the population will be protected due to the advent and widespread use of the HPV vaccine, the treatment of cervical cancer for all causes, including HPV-negative cervical cancer, is still worthy of further research. The focal point of this study was Canadine's inhibition of epithelial-mesenchymal transformation (EMT) in cervical cancer. Immunoblotting, wound healing and tumor invasion experiments showed that low concentration of Canadine could inhibit the EMT process, proliferation and migration of HT-3 cells (HPV-negative cell line). Combined with GEO database, it was found that the expression levels of several genes highly expressed in cervical tumor tissues could be inhibited by Canadine, especially MAGEA3. Further experiments confirmed that the inhibition of Canadine on MAGEA3 protein increased with time. The small interference and overexpression plasmid of MAGEA3 were designed and verified. In HT-3 cells, when MAGEA3 levels were directly decreased, mesenchymal phenotypic markers were decreased and epithelial phenotypic markers were increased. The opposite result was obtained by overexpression of MAGEA3. In addition, the inhibition of EMT due to the reduction of endogenous MAGEA3 by Canadine was also offset by the overexpression of exogenous MAGEA3. The study concludes that Canadine inhibits EMT of cervical cancer by inhibiting MAGEA3.

Organocatalytic Asymmetric [4 + 2] Cyclization of Azadienes with Azlactones: Access to Chiral 3-Amino-δ-Lactams Derivatives

Herein, a series of chiral δ-lactam frameworks have been synthesized and catalyzed by chiral phosphoric acid (CPA) utilizing two kinds of open-chain aza-dienes and azlactones derived from amino acids. This powerful [4 + 2] annulation produces a broad substrate scope with functional group tolerance in yield up to 97% with up to 98:2 er. Moreover, a facile scale-up and straightforward conversion to diversely substituted products verify the synthetic utility of this method featuring good compatibility and high efficiency.

An Ultrastable Bifunctional Electrocatalyst Derived from a Co2+-Anchored Covalent-Organic Framework for High-Efficiency ORR/OER and Rechargeable Zinc-Air Battery

It remains a great challenge to develop alternative electrocatalysts with high stability for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Herein, a bifunctional electrocatalyst composed of hollow CoOx (Co3O4/CoO) nanoparticles embedded in lamellar carbon nanofibers is derived from a Co2+-anchored covalent-organic framework. The as-fabricated electrocatalyst (CoOx@NC-800) exhibits a half-wave potential (E1/2) of 0.89 V with ultrahigh long-term stability (100% current retention after 3000 CV cycles). Together with promising OER performance, the CoOx@NC-800 based reversible Zn-air battery displays a small potential gap (0.70 V), superior to that of the commercial 20% Pt/C + RuO2. The density functional theory (DFT) calculations reveal that the remarkable electrocatalytic performance and stability of CoOx@NC-800 are attributed to the optimized adsorption of the *OOH intermediate and reduced free energy of the potential-limiting step. This study establishes the functionalization of COF structure for fabrication of high-performance carbon-based electrocatalysts.

Cross-Platform Transcriptomic Data Integration, Profiling, and Mining in Vibrio cholerae

A large number of transcriptome studies generate important data and information for the study of pathogenic mechanisms of pathogens, including Vibrio cholerae. V. cholerae transcriptome data include RNA-seq and microarray: microarray data mainly include clinical human and environmental samples, and RNA-seq data mainly focus on laboratory processing conditions, including different stresses and experimental animals in vivo. In this study, we integrated the data sets of both platforms using Rank-in and the Limma R package normalized Between Arrays function, achieving the first cross-platform transcriptome data integration of V. cholerae. By integrating the entire transcriptome data, we obtained the profiles of the most active or silent genes. By transferring the integrated expression profiles into the weighted correlation network analysis (WGCNA) pipeline, we identified the important functional modules of V. cholerae in vitro stress treatment, gene manipulation, and in vitro culture as DNA transposon, chemotaxis and signaling, signal transduction, and secondary metabolic pathways, respectively. The analysis of functional module hub genes revealed the uniqueness of clinical human samples; however, under specific expression patterning, the Δhns, ΔoxyR1 strains, and tobramycin treatment group showed high expression profile similarity with human samples. By constructing a protein-protein interaction (PPI) interaction network, we discovered several unreported novel protein interactions within transposon functional modules. IMPORTANCE We used two techniques to integrate RNA-seq data for laboratory studies with clinical microarray data for the first time. The interactions between V. cholerae genes were obtained from a global perspective, as well as comparing the similarity between clinical human samples and the current experimental conditions, and uncovering the functional modules that play a major role under different conditions. We believe that this data integration can provide us with some insight and basis for elucidating the pathogenesis and clinical control of V. cholerae.

Palladium-catalyzed asymmetric [4+2] annulation of vinyl benzoxazinanones with pyrazolone 4,5-diones to access spirobenzoxazine frameworks

Herein, a palladium-catalyzed general synthetic strategy to access an attractive and decorated set of chiral spiro derivatives of benzoxazine compounds is unveiled utilizing vinyl benzoxazinanones reacted with pyrazolone 4,5-diones, which extends the application of vinyl benzoxazinanones with ketones. This asymmetric catalytic [4+2] cycloaddition reaction demonstrates a broad substrate scope with functional group tolerance in yields of up to 76% and up to 96% ee. A facile scale-up and straightforward conversion to diversely substituted products verify the synthetic utility of this method.

[Single-center study of different treatment for advanced or unresectable angiosarcoma patients]

Objective: To evaluate the efficacy and safety of different medical treatment in advanced or unresectable angiosarcoma. Methods: This study was a single-center retrospective clinical study. Fifty-five advanced or unresectable angiosarcoma patients treated in Sun-Yat Sen University Cancer Center from January 2005 to August 2020 were enrolled. There were 34 patients who received first-line doxorubicin-based chemotherapy (doxorubicin group), 12 patients received first-line doxorubicin or liposome doxorubicin plus paclitaxel or albumin bound paclitaxel chemotherapy (combination therapy group), and 4 patients received first-line paclitaxel-based treatment (paclitaxel group). There were 6 patients who received anti-angiogenesis targeted therapy, another 2 patients received anti-PD-1 antibody plus anti-angiogenesis targeted therapy. Targeted therapy and immunotherapy plus targeted therapy included 5 cases of first-line therapy and 3 cases of second-line therapy. The therapeutic effect was evaluated by RECIST 1.1 standard. The adverse reactions were evaluated by CTCAE4.0 standard. Kaplan-Meier survival analysis was evaluated with Log rank test. Cox proportional hazard model was used to analyze the influencing factors. Results: There were 18 patients achieved partial response (PR) in 34 patients in the doxorubicin group, median progression-free survival (mPFS) was 4.5 months, and median overall survival (mOS) was 15 months. Four patients achieved PR in 12 patients in the combination therapy group, mPFS and mOS were 4 months and 19 months. Two patients achieved PR in 4 patients in the paclitaxel group, mPFS and mOS were 3 months and 9 months. However, only 1 in 6 patients achieved PR for anti-angiogenesis targeted therapy, mPFS and mOS were 3 months and 16 months. Two patients who received anti-PD-1 immunotherapy combined with anti-angiogenesis targeted therapy acquired PR for 17 months and more than 16 months. Median PFS (7.5 months) were longer in those with primary liver, lung and spleen angiosarcoma than in those with other primary site (3.0 months, P=0.028). The mOS (20 months) was longer in females than that in males (12 months, P=0.045). Primary tumor site, sex, age and treatment were not independent prognostic factors for angiosarcoma patients (P>0.05). Grade 3-4 cardiac toxicity was found in 2 patients in the combination therapy group. Conclusions: Doxorubicin-based and paclitaxel-based chemotherapy are the most important treatment for advanced angiosarcoma. Potential efficacy for targeted therapy combined with anti-PD-1 immunotherapy are showed in some patients with long duration of response and moderate adverse event.

Cooperative photoactivation/Lewis base catalyzed [4+2] annulations of α-diazoketones and ortho-amino MBH carbonates to access dihydroquinolinone frameworks

A series of multifunctional dihydroquinolinone frameworks have been synthesized via synergistic catalysis combining photolysis and Lewis base catalysis utilizing in situ generated ketenes from the visible-light-mediated Wolff rearrangement of α-diazoketones...

Overexpression of SmLAC25 promotes lignin accumulation and decreases salvianolic acid content in Salvia miltiorrhiza

Laccase (LAC) is a blue multicopper oxidase that contains four copper ions, which is involved in lignin polymerization and flavonoid biosynthesis in plants. Although dozens of LAC genes have been identified in Salvia miltiorrhiza Bunge (a model medicinal plant), most have not been functionally characterized. Here, we explored the expression patterns and the functionality of SmLAC25 in S. miltiorrhiza. SmLAC25 has a higher expression level in roots and responds to methyl jasmonate, auxin, abscisic acid, and gibberellin stimuli. The SmLAC25 protein is localized in the cytoplasm and chloroplasts. Recombinant SmLAC25 protein could oxidize coniferyl alcohol and sinapyl alcohol, two monomers of G-lignin and S-lignin. To investigate its function, we generated SmLAC25-overexpressed S. miltiorrhiza plantlets and hairy roots. The lignin content increased significantly in all SmLAC25-overexpressed plantlets and hairy roots, compared with the controls. However, the concentrations of rosmarinic acid and salvianolic acid B decreased significantly in all the SmLAC25-overexpressed lines. Further studies revealed that the transcription levels of some key enzyme genes in the lignin synthesis pathway (e.g., SmCCR and SmCOMT) were significantly improved in the SmLAC25-overexpressed lines, while the expression levels of multiple enzyme genes in the salvianolic acid biosynthesis pathway were inhibited. We speculated that the overexpression of SmLAC25 promoted the metabolic flux of lignin synthesis, which resulted in a decreased metabolic flux to the salvianolic acid biosynthesis pathway.

Effect of pediatric- versus adult-type chemotherapy regimens on outcomes of allogeneic hematopoietic stem cell transplants for adult T-cell acute lymphoblastic leukemia in first complete remission

The optimal chemotherapy regimen pre-transplantation for adult T-cell acute lymphoblastic leukemia (T-ALL) patients remains unknown. Here, we compared the transplant outcomes in 127 subjects receiving pediatric- (N = 57) or adult-type (N = 70) regimens pre-transplant. The corresponding 3-year cumulative incidences of relapse (CIR) was 7% (95% CI: 3-11%) and 29% (95% CI: 23-35%; P = 0.02), leukemia-free survivals (LFS) was 86% (95% CI: 81-91%) and 57% (95% CI: 51-63%; P = 0.003), overall survivals (OS) was 88% (95% CI: 84-92%) and 58% (95% CI: 52-64%; P = 0.002), the 1-year NRM was 4% (95% CI: 1-7%) and 9% (95% CI: 4-14%; P = 0.40). Multivariate analysis showed that pediatric-type regimen was associated with lower CIR (Hazard Ratio [HR] = 0.31 [95% CI: 0.09-1.00]; P = 0.05), better LFS (HR = 0.34 [95% CI: 0.15-0.78]; P = 0.01) and OS (HR = 0.30 [95% CI: 0.13-0.72]; P = 0.01). Our results suggested that adult T-ALL patients undergoing allo-HSCT might benefit from pediatric-type chemotherapy.

A reverse transcription-cross-priming amplification method with lateral flow dipstick assay for the rapid detection of Bean pod mottle virus

Bean pod mottle virus (BPMV) is a destructive virus that causes serious economic losses in many countries every year, highlighting the importance of its effective detection. In this study, we developed a fast reverse transcription-cross-priming amplification (RT-CPA) coupled with lateral flow dipstick (LFD) diagnostic method for BPMV detection. The RT-CPA-LFD assay that targets the coat protein gene of BPMV was highly specific against diagnosing four other common viruses transmitted by soybean seeds, i.e., Southern bean mosaic virus (SBMV), Tomato ringspot virus (ToRSV), Arabis mosaic virus (ArMV), and Tobacco ringspot virus (TRSV). The sensitivities of the real-time fluorescent RT-CPA and the RT-CPA-LFD assay were at least 50 pg/μl and 500 pg/μl, respectively. Despite a compromise in the limit of detection of the RT-CPA method compared with TaqMan-MGB real-time RT-PCR, our results demonstrated a notably better performance in the detection of field samples of BPMV-infested soybean seeds. With the advantages of efficiency and convenience by visual determination, the RT-CPA-LFD assay presents a potential application for the rapid and accurate detection of BPMV in routine tests.

Visible-Light-Mediated Sequential Wolff Rearrangement and Staudinger Cycloaddition Enabling Assembly of Spiro-Pyrazolone-β-Lactams

Visible-light-mediated sequential Wolff rearrangement and Staudinger cycloaddition for the assembly of valuable spiro-pyrazolone-β-lactams for the first time is disclosed by utilizing in situ generated ketenes and pyrazolone ketimines. This powerful...

An inducible constitutive expression system in Bombyx mori mediated by phiC31 integrase

Inducible gene-expression systems play important roles in gene functional assays in the post-genome era. Streptomyces phage-derived phiC31 integrase, which mediates an irreversible site-specific cassette exchange between the phage attachment site (attP) and the bacterial attachment site (attB), provides a promising option for the construction of a controllable gene-expression system. Here, we report a phiC31 integrase-mediated promoter flip system (FLIP) for the inducible expression of target genes in silkworm (Bombyx mori). First, we constructed a FLIP reporter system, in which a BmAct4 promoter with enhanced translational efficiency was flanked by the attB and attP sites in a head-to-head orientation and further linked in a reverse orientation to a DsRed reporter gene. The coexpression of a C-terminal modified phiC31-NLS integrase carrying a simian virus 40 (SV40) nuclear localization signal (NLS) effectively flipped the BmAct4 promoter through an attB/attP exchange, thereby activating the downstream expression of DsRed in a silkworm embryo-derived cell line, BmE. Subsequently, the FLIP system, together with a system continuously expressing the phiC31-NLS integrase, was used to construct binary transgenic silkworm lines. Hybridization between FLIP and phiC31-NLS transgenic silkworm lines resulted in the successful flipping of the BmAct4 promoter, with an approximately 39% heritable transformation efficiency in silkworm offspring, leading to the constitutive and high-level expression of DsRed in silkworms, which accounted for approximately 0.81% of the silkworm pupal weight. Our successful development of the FLIP system offers an effective alternative for manipulating gene expression in silkworms and other lepidopteran species.

[Application of multi-state Markov model in studying transition of number of chronic complications and influencing factors in type 2 diabetes mellitus patients]

Objective: To establish a multi-state Markov model of type 2 diabetes mellitus (T2DM) patients and explore the transition rule between the cumulative number of different chronic complications, estimate the transition probability and intensity between status, and explore the possible factors affecting the transition between status. Methods: A retrospective cohort study of 33 575 patients with T2DM was conducted. According to the baseline and the cumulative number of chronic complications during the follow-up period, the patients were classified based on five status: T2DM, one complication, two complications, three complications, four and above complication, indicated by S0, S1, S2, S3 and S4, respectively. A time-continuous and state-discrete multi-state irreversible Markov model was used for statistical analysis. Results: The study included 33 575 T2DM patients, and their average age was 60 years old, the median of follow-up length was 8 years. In these patients, 32 653 had no baseline complications. At the end of follow-up, the transition probabilities of S0→S1, S1→S2, S2→S3 and S3→S4 were 16.4%, 32.4%, 45.6% and 25.9%, respectively. The results of multivariate analysis showed that being female (HR=0.919), less than 60 years old (HR=0.929), higher fasting plasma glucose (HR=1.601), lower high-density lipoprotein (HR=1.087), higher total cholesterol (HR=1.090),weekly exercise (HR=0.897), vegetarian diet (HR=0.852) and heavy diet (HR=1.887) were the risk factors for S0 to S1. And being female (HR=0.768), less than 60 years old (HR=0.859) and lower high-density lipoprotein (HR=1.160) were the risk factors for S1 to S2. Conclusions: The probability of multiple complications in T2DM patients increased over time, the transition intensity of S2→S3 was largest, followed by S1→S2. Therefore, we need to conduct both early and long-term indicators monitoring and disease prevention, strengthen the health education to improve patients' daily living habits at early stage of the illness, encourage patients to have moderate exercise and balanced diet, strengthen the monitoring of fasting blood- glucose, cholesterol and high-density lipoprotein levels to prevent the deterioration of the illness.

Correction to: The lncRNA LAMP5-AS1 drives leukemia cell stemness by directly modulating DOT1L methyltransferase activity in MLL leukemia

The original article [1] contains an error in Fig. 6b for the image of western blot panels.

[Study on therapeutic mechanism of Rehmanniae Radix Praeparata- Corni Fructus in sequelae of ischemic stroke based on network pharmacology technology]

In ischemic stroke sequela phase, Rehmanniae Radix Praeparata-Corni Fructus drug pair has the effect in protecting damaged neurons, but its mechanism has not been clear. In this study, network pharmacology was used to predict the mechanism of Rehmanniae Radix Praeparata-Corni Fructus in the treatment of ischemic stroke sequela. Through database search and literature retrie-val, 40 active ingredients of Rehmanniae Radix Praeparata and Corni Fructus were obtained, and their targets were obtained through STITCH and TCMSP databases. The targets of ischemic stroke sequela were obtained through OMIM,GAD,TTD and DrugBank databases. By screening the intersections of active ingredients targets and stroke treatment targets, 21 potential targets were obtained. The DAVID database was used for GO enrichment analysis and KEGG pathway analysis of potential targets. GO enrichment analysis showed that Rehmanniae Radix Praeparata-Corni Fructus were mainly involved in regulation of blood pressure, negative regulation of extrinsic apoptotic signaling and positive regulation of angiogenesis. KEGG pathway analysis showed that Rehmanniae Radix Praeparata-Corni Fructus could inhibit inflammatory response and apoptosis signaling pathway by regulating HIF-VEGFA signaling pathway in neural stem cell proliferation, TNF signaling pathway and NF-kappaB signaling pathway. Molecular docking technique was used to verify that Rehmanniae Radix Praeparata-Corni Fructus component has a good binding activity with potential targets. The results showed that in ischemic stroke sequela phase, Rehmanniae Radix Praeparata-Corni Fructus drug pair could play an important role in recovering neural function, promoting the proliferation of neural stem cells, angiogenesis, preventing neural cells apoptosis and regulating inflammatory factors.

Introgressive hybridization between two non-native apple snails in China: widespread hybridization and homogenization in egg morphology

BACKGROUND

Apple snails from the genus Pomacea have spread widely in paddy fields and other wetlands of southern China since their introduction in the 1980s. Pomacea spp. are commonly identified using mitochondrial COI sequences. However, sequencing the nuclear elongation factor 1-alpha (EF1α) gene revealed genetic introgression between field populations of P. canaliculata and P. maculata, which produce surviving hybrids in laboratory crossbreeding experiments.

RESULTS

In this study, we sequenced 1054 EF1α clones to design specific primers and established a fast and accurate multiplex polymerase chain reaction (PCR) method for genotyping EF1α. Combined with genotyping P. canaliculata and P. maculata based on mitochondrial COI and nuclear EF1α, we revealed the genetic introgression patterns of 30 apple snail populations in China. Purebred and hybrid individuals of P. canaliculata were widely distributed, while pure maculata-EF1α type was detected only in a few individuals identified as P. canaliculata based on COI sequences. Each egg clutch had one to three genetic patterns, indicating multiple paternity or segregation in the progeny of hybrids. The higher percentages of hybrids in both wild populations and progeny than the homozygotes indicated a potential heterosis in the apple snail populations. Additionally, egg size and clutch size of the apple snails became homogeneous among the non-native populations exhibiting introgression hybridization.

CONCLUSION

Our findings emphasize the value of apple snails as a model to study the mechanisms and impacts of introgressive hybridization on fitness traits. © 2020 Society of Chemical Industry.

Cis-acting lnc-eRNA SEELA directly binds histone H4 to promote histone recognition and leukemia progression

Background

Long noncoding enhancer RNAs (lnc-eRNAs) are a subset of stable eRNAs identified from annotated lncRNAs. They might act as enhancer activity-related therapeutic targets in cancer. However, the underlying mechanism of epigenetic activation and their function in cancer initiation and progression remain largely unknown.

Results

We identify a set of lncRNAs as lnc-eRNAs according to the epigenetic signatures of enhancers. We show that these lnc-eRNAs are broadly activated in MLL-rearranged leukemia (MLL leukemia), an aggressive leukemia caused by a chromosomal translocation, through a mechanism by which the HOXA cluster initiates enhancer activity, and the epigenetic reader BRD4 cooperates with the coregulator MLL fusion oncoprotein to induce transcriptional activation. To demonstrate the functional roles of lnc-eRNAs, two newly identified lnc-eRNAs transcribed from the SEELA eRNA cluster (SEELA), SEELA1 and SEELA2, are chosen for further studies. The results show that SEELA mediated cis-activated transcription of the nearby oncogene Serine incorporate 2 (SERINC2) by directly binding to the K31 amino acid (aa) of histone H4. Chromatin-bound SEELA strengthens the interaction between chromatin and histone modifiers to promote histone recognition and oncogene transcription. Further studies show that the SEELA-SERINC2 axis regulated aspects of cancer metabolism, such as sphingolipid synthesis, to affect leukemia progression.

Conclusions

This study shows that lnc-eRNAs are epigenetically activated by cancer-initiating oncoproteins and uncovers a cis-activating mechanism of oncogene transcription control based on lnc-eRNA-mediated epigenetic regulation of enhancer activity, providing insights into the critical roles of lnc-eRNAs in cancer initiation and progression.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s13059-020-02186-x.

The Association between Diabetes Complications, Diabetes Distress, and Depressive Symptoms in Patients with Type 2 Diabetes Mellitus

This study investigated the association between diabetes complications, diabetes distress, and depressive symptoms in patients with type 2 diabetes mellitus. A total of 600 patients with type 2 diabetes mellitus were included in this study. Data were collected using the Diabetes Distress Scale and the nine-item Patient Health Questionnaire. The results showed that both diabetes complications and diabetes distress were positively associated with depressive symptoms, and diabetes distress attenuated the association between diabetes complications and depressive symptoms. The Sobel test confirmed the mediating effect of diabetes distress. Patients with both diabetes complications and diabetes distress had a higher risk of depressive symptoms than those with diabetes complications or diabetes distress alone. This study indicates that the positive association between diabetes complications and depressive symptoms is persistent and mediated by diabetes distress, and the comorbidity of diabetes complications and diabetes distress has an additive interaction effect on depressive symptoms.

The lncRNA LAMP5-AS1 drives leukemia cell stemness by directly modulating DOT1L methyltransferase activity in MLL leukemia

BACKGROUND

Mixed-lineage leukemia (MLL) gene rearrangements trigger aberrant epigenetic modification and gene expression in hematopoietic stem and progenitor cells, which generates one of the most aggressive subtypes of leukemia with an apex self-renewal. It remains a challenge to directly inhibit rearranged MLL itself because of its multiple fusion partners and the poorly annotated downstream genes of MLL fusion proteins; therefore, novel therapeutic targets are urgently needed.

METHODS

qRT-PCR, receiver operating characteristic (ROC), and leukemia-free survival analysis were used to validate LAMP5-AS1 (LAMP5 antisense 1) expression and evaluate its clinical value. We performed in vitro and in vivo experiments to investigate the functional relevance of LAMP5-AS1 in MLL leukemia progression and leukemia cell stemness. RNA electrophoretic mobility shift assays (EMSA), histone methyltransferase assay, RNA pull-down assay, and RNA fluorescence in situ hybridization (FISH) were used to validate the relationship between LAMP5-AS1 and the methyltransferase activity of DOT1L. The downstream ectopic target genes of LAMP5-AS1/DOT1L were validated by the chromatin immunoprecipitation (ChIP) and western blot.

RESULTS

We discovered that a long noncoding RNA (lncRNA) LAMP5-AS1 can promote higher degrees of H3K79 methylation, followed by upregulated expression of the self-renewal genes in the HOXA cluster, which are responsible for leukemia stemness in context of MLL rearrangements. We found that LAMP5-AS1 is specifically overexpressed in MLL leukemia patients (n = 58) than that in the MLL-wt leukemia (n = 163) (p < 0.001), and the patients with a higher expression level of LAMP5-AS1 exhibited a reduced 5-year leukemia-free survival (p < 0.01). LAMP5-AS1 suppression significantly reduced colony formation and increased differentiation of primary MLL leukemia CD34+ cells. Mechanistically, LAMP5-AS1 facilitated the methyltransferase activity of DOT1L by directly binding its Lys-rich region of catalytic domain, thus promoting the global patterns of H3K79 dimethylation and trimethylation in cells. These observations supported that LAMP5-AS1 upregulated H3K79me2/me3 and the transcription of DOT1L ectopic target genes.

CONCLUSIONS

This is the first study that a lncRNA regulates the self-renewal program and differentiation block in MLL leukemia cells by facilitating the methyltransferase activity of DOT1L and global H3K79 methylation, showing its potential as a therapeutic target for MLL leukemia.

Spatial distribution of perfluoroalkyl acids (PFAAs) and their precursors and conversion of precursors in seawater deeply affected by a city in China

Conversion of perfluoroalkyl acid (PFAA) precursors in the environment has been a hotspot research in recent years. This study firstly determined the spatial distribution of PFAAs and their precursors including 8:2 fluorotelomer unsaturated acid (8:2 FTUCA), perfluorooctane sulfoneamide (FOSA), and diperfluorooctane sulfonamido ethanol-based phosphate (di-SAmPAP), then investigated the conversion of the potential precursors in the seawater and sewage treatment plants (STPs) effluents. The results indicated that the target pollutants showed a typical concentration gradient from nearshore to offshore. And the obviously increased concentration of perfluorinated carboxylic acids (△[PFCAs]) after oxidation treatment can verify the existence of PFAA precursors in the seawater and STP effluents. The concentrations of PFCAs with carbon atom numbers 4-9 (PFCA_C4-C9) revealed the most increase. Moreover, the levels of △[PFCAs] and the ratios of △[PFCAs] to their concentration before oxidation (△[PFCA]/[PFCA]_{before oxidation}) indicated obvious spatial variations in the seawater and STP effluents. The higher levels of △[PFCA_C4-C12] and the lower ratios of ∑△[PFCA_C4-C12]/∑[PFAA]_{before oxidation} were observed in the STP effluents, which implied that precursors might be decomposed during the sewage treatment process. These results suggested the STP effluents might have an important effect on the PFAAs levels of seawater.

Positive Association Between Serum Levels of High-Sensitivity C-Reactive Protein and Depression/Anxiety in Female, but Not Male, Patients With Type 2 Diabetes Mellitus

Purpose:

Patients with Type 2 diabetes (T2D) have increased risk of depression and anxiety. Evidence suggests that a heightened inflammatory state may contribute to this association. Females experience more depression and higher inflammation levels than males. This study compared associations of serum high-sensitivity C-reactive protein (hs-CRP) levels with symptoms of depression and anxiety between men and women with Type 2 diabetes mellitus (T2DM).

Method:

Cross-sectional data including demographic and disease characteristics, symptoms of depression and anxiety, clinical data, and laboratory values were collected from 392 patients with T2DM recruited from a general hospital in Shandong Province, China. We evaluated associations between serum hs-CRP level and symptoms of depression and anxiety in males and females separately using multiple linear regressions and χ2 tests for trend.

Results:

Sex moderated the association between serum hs-CRP level and symptoms of depression ( B = .112 [ SE = 0.049]; p = .022) and anxiety ( B = .137 [ SE = 0.053]; p = .011). Among females, hs-CRP level was positively associated with depression ( B = .034, 95% confidence interval [CI] = [.006, .061]; p = .016, false discovery rate [FDR]-adjusted p = .020) and anxiety ( B = .041, 95% CI [.011, .071], p = .007, FDR-adjusted p = .007). Positive trends indicated a higher prevalence of clinically significant symptoms of depression and anxiety in higher serum hs-CRP categories in females. No associations were found in males.

Conclusion:

Findings demonstrate that associations between serum hs-CRP level and symptoms of depression and anxiety in patients with T2D are sex-specific, with only females demonstrating a significant positive association.

Delivery of cell membrane impermeable peptides into living cells by using head-to-tail cyclized mitochondria-penetrating peptides

A series of cyclic Arg-rich mitochondria-penetrating peptides were prepared with variation in the macrocycle size and the chirality of Arg residues. A cyclic heptapeptide was demonstrated to be an efficient mitochondria-specific delivery vector for delivering membrane impermeable peptides.

circRNA circAF4 functions as an oncogene to regulate MLL-AF4 fusion protein expression and inhibit MLL leukemia progression

Background

Circular RNAs (circRNAs) represent a type of endogenous noncoding RNAs that are generated by back-splicing events and favor repetitive sequences. Recent studies have reported that cancer-associated chromosomal translocations could juxtapose distant complementary repetitive intronic sequences, resulting in the aberrant formation of circRNAs. However, among the reported fusion genes, only a small number of circRNAs were found to originate from fusion regions during gene translocation. We question if circRNAs could also originate from fusion partners during gene translocation.

Methods

Firstly, we designed divergent primers for qRT-PCR to identify a circRNA circAF4 in AF4 gene and investigated the expression pattern in different types of leukemia samples. Secondly, we designed two small interfering RNAs specially targeting the back-spliced junction point of circAF4 for functional studies. CCK8 cell proliferation and cell cycle assay were performed, and a NOD-SCID mouse model was used to investigate the contribution of circAF4 in leukemogenesis. Finally, luciferase reporter assay, AGO2 RNA immunoprecipitation (RIP), and RNA Fluorescent in Situ Hybridization (FISH) were performed to confirm the relationship of miR-128-3p, circAF4, and MLL-AF4 expression.

Results

We discovered a circRNA, named circAF4, originating from the AF4 gene, a partner of the MLL fusion gene in MLL-AF4 leukemia. We showed that circAF4 plays an oncogenic role in MLL-AF4 leukemia and promotes leukemogenesis in vitro and in vivo. More importantly, knockdown of circAF4 increases the leukemic cell apoptosis rate in MLL-AF4 leukemia cells, while no effect was observed in leukemia cells that do not carry the MLL-AF4 translocation. Mechanically, circAF4 can act as a miR-128-3p sponge, thereby releasing its inhibition on MLL-AF4 expression. We finally analyzed most of the MLL fusion genes loci and found that a number of circRNAs could originate from these partners, suggesting the potential roles of fusion gene partner-originating circRNAs (named as FP-circRNAs) in leukemia with chromosomal translocations.

Conclusion

Our findings demonstrate that the abnormal elevated expression of circAF4 regulates the cell growth via the circAF4/miR-128-3p/MLL-AF4 axis, which could contribute to leukemogenesis, suggesting that circAF4 may be a novel therapeutic target of MLL-AF4 leukemia.

Promising High-Confinement Regime for Steady-State Fusion

A reproducible stationary high-confinement regime with small "edge-localized modes" (ELMs) has been achieved recently in the Experimental Advanced Superconducting Tokamak, which has a metal wall and low plasma rotation as projected for a fusion reactor. We have uncovered that this small ELM regime is enabled by a wide edge transport barrier (pedestal) with a low density gradient and a high density ratio between the pedestal foot and top. Nonlinear simulations reveal, for the first time, that the underlying mechanism for the observed small ELM crashes is the upper movement of the peeling boundary induced by an initial radially localized collapse in the pedestal, which stops the growth of instabilities and further collapse of the pedestal, thus providing a physics basis for mitigating ELMs in future steady-state fusion reactors.

Effectiveness of two guided self-administered interventions for psychological distress among women with infertility: a three-armed, randomized controlled trial

STUDY QUESTION

What is the effect of two guided self-administered interventions on psychological distress in women undergoing IVF or ICSI?

SUMMARY ANSWER

A brief mindfulness intervention significantly reduced depression and improved sleep quality, while the gratitude journal intervention showed no significant effect on any outcome variables.

WHAT IS KNOWN ALREADY

Mindfulness and gratitude journal interventions have been found to be beneficial in reducing negative affect and improving well-being. However, there are very few mental health professionals who implement such interventions in low- and middle-income countries. Therefore, two guided self-administered interventions for women with infertility were designed to help them cope with their psychological distress.

STUDY DESIGN, SIZE, DURATION

A three-armed, randomized controlled trial was designed to evaluate the mindfulness and gratitude journal interventions for women undergoing IVF/ICSI. Between May 2016 and November 2017, at the reproductive center in a public hospital, 234 women were randomly assigned to the brief mindfulness group (BMG, n = 78), gratitude journal group (GJG, n = 78) or control group (CG, n = 78). The inclusion criteria were being a woman undergoing her first cycle of IVF, having at least junior middle school education and having no biological or adopted children.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Female infertility patients (n = 346) were approached, and 112 did not meet the inclusion criteria. All three randomized groups completed questionnaires on the day of down-regulation (T1), the day before embryo(s) transfer (T2), and 3 days before the pregnancy test (T3). The BMG completed four sessions and listened to a 20-minute audio daily, including guided mindfulness breathing and body scan. The GJG completed four sessions and wrote three gratitude journals daily. The CG received routine care. A generalized estimating equation was used in an intention-to-treat analysis. The primary outcome was depression. Secondary outcomes were anxiety, sleep quality, infertility-related stress, mindfulness and gratitude.

MAIN RESULTS AND THE ROLE OF CHANCE

Participants of the BMG showed decreased depression (mean difference (MD) = −1.69, [−3.01, −0.37], d = 0.44) and improved sleep quality (MD = −1.24, [−1.95, −0.39], d = 0.43) compared to the CG, but the effect was not significant for anxiety, Fertility Problem Inventory totals, mindfulness, gratitude scores or pregnancy rates. The BMG showed a significant reduction in depression and improvement in sleep quality between T1 and T2, a continuous significant reduction between T1 and T3 and no reduction between T2 and T3. There were no significant effects on any of the variables for the GJG.

LIMITATIONS, REASONS FOR CAUTION

The inclusion criteria may result in bias because some participants with low education were excluded and only women with infertility were included. A low compliance rate occurred in the gratitude journals group. Moreover, men were not included in this study. Further research should consider including spouses of the target population.

WIDER IMPLICATIONS OF THE FINDINGS

The brief mindfulness intervention was beneficial in decreasing depression and improving sleep quality. Implementation of guided self-administered mindfulness could make the psychological counseling service more accessible for patients with infertility in resource-poor settings. The efficiency and feasibility of the gratitude journal intervention needs to be investigated further.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the National Social Science Foundation (17BSH054). The authors have no conflicts of interest.

TRIAL REGISTRATION NUMBER

ChiCTR-IOR-16008452.

TRIAL REGISTRATION DATE

9 May 2016

DATE OF FIRST PATIENT’S ENROLMENT

15 May 2016.

Transesophageal Echocardiographic Measurements of the Superior Vena Cava for Predicting Fluid Responsiveness in Patients Undergoing Invasive Positive Pressure Ventilation

OBJECTIVES

Preoperative fasting, water deprivation, and intraoperative fluid loss and redistribution result in hypovolemia in patients undergoing surgery. Some findings have indicated that the superior vena cava (SVC) diameter and variation, as determined by transesophageal echocardiography during surgery, do not reflect central venous pressure effectively. This study aimed to compare and correlate the SVC diameter and variation with the stroke volume variation for predicting fluid responsiveness in patients undergoing invasive positive pressure ventilation.

METHODS

Thirty-six patients scheduled for elective gastrointestinal surgery under general anesthesia with invasive positive pressure ventilation were included in this study. After anesthesia induction, the stroke volume variation, SVC diameter, mean arterial pressure, central venous pressure, and pulse were recorded, and measurements after fluid challenge were recorded as well. The SVC variation was calculated before and after the fluid challenge.

RESULTS

After the fluid challenge, the SVC diameter markedly increased, whereas the SVC variation and stroke volume variation significantly decreased (P < .05). The optimal cutoff value for the SVC variation was 21.1%, and the area under the curve (AUC) from a receiver operating characteristic curve analysis was 0.849. The optimal cutoff value for the minimal SVC diameter was 1.135 cm, and that AUC was 0.929. In addition, the optimal cutoff value for the maximal SVC diameter was 1.480 cm, and the AUC was 0.862.

CONCLUSIONS

The minimal SVC diameter may be an effective indicator for predicting fluid responsiveness in patients undergoing invasive positive pressure ventilation.

[Prevalence of attention deficit and hyperactivity disorder in children in China: a systematic review and Meta-analysis]

Objective: To understand the prevalence of attention deficit and hyperactivity disorder (ADHD) in children in China and provide scientific basis for early prevention and treatment of ADHD in children. Methods: A systematic literature retrieval was conducted by using CNKI, Wanfang data, CBM and VIP databases for the information about the prevalence of ADHD in children in China published from 1979 to 2017. Pubmed database was used to retrieve the literatures about ADHD prevalence in children in China published from 1946 to 2017. The quality of literature was evaluated based on the cross-sectional study criteria according to STROBE statement. Stata 12.0 was used for combined prevalence and subgroup analyses, including gender, regions, publication year, diagnostic criteria, sampling methods, and so on. Egger testing and the evaluation of funnel graph were used to evaluate the publication bias of these literatures, and sensitivity analysis was done by using different models and eliminating the influence of any one of these articles on combined effect value. Results: Twenty articles were included. The total sample size was 88 755, including 46 216 boys and 42 539 girls. The prevalence of ADHD in children in China was 5.6% (95%CI: 5.0%-6.3%). The prevalence was 7.7% (95%CI: 6.7%-8.8%) in boys and 3.4% (95%CI: 3.0%-3.8%) in girls, the difference was statistically significant (P<0.05). No statistically significance difference in the ADHD prevalence was observed between different regions publication years, diagnostic criteria and sampling methods. Conclusions: The prevalence of ADHD in children in China was high, and boys tended to have a higher prevalence compared with girls. Appropriate screening methods for early detection and intervention conduction of ADHD should be taken among children in China.

[HSP90 inhibitor 17-AAG plays an important role in JAK3/STAT5 signaling pathways in HTLV-1 infection cell line HUT-102]

Objective: To analyze whether heat-shock protein 90 (HSP90) be involved in a permanently abnormal activated JAK/STAT signaling in ATL cells in vitro. Methods: The effect of 17-AAG on proliferation of ATL cell lines HUT-102 was assessed using CCK8 at different time points. Cell apoptosis was measured by flow cytometry. The specific proteins HSP90, STAT5, p-STAT5 and JAK3 were detected by Western blotting. Results: Overexpression of HSP90 in HUT-102 cell lines was disclosed (P<0.05) , and constitutive activation of JAK3/STAT5 signaling was observed in HTLV-1-infected T-cell lines but not in normal PBMCs; Treatment of ATL cell lines with 17-AAG led to reduced cell proliferation, but there was no significant change in terms of cell proliferation when the concentration of 17-AAG between 2 000-8 000 nmol/L (P>0.05) . 17-AAG induced cell apoptosis in different time-points and concentrations. 17-AAG don't affect the expression of JAK3 gene. Conclusion: This study indicated that JAK3 as HSP90 client protein was aberrantly activated in HTLV-1-infected T-cell lines, leading to constitutive activation of p-STAT5 in JAK/STAT signal pathway, which demonstrated that HSP90-inhibitors 17-AAG inhibited the growth of HTLV-1-infected T-cell lines by reducing cell proliferation and inducing cell apoptosis.

Comparison of the strength of two multi-strand tendon repair configurations in a chicken model

We sought to investigate the strength of two multi-strand tendon repair configurations in a chicken model. Fifty-six chicken flexor tendons were repaired with one to two different four-strand configurations: 1) a four-strand repair consisting of a two-strand core modified Kessler suture with a circle loop repair and 2) a four-strand core Kessler suture repair with three separate peripheral suture points. The strength of the repaired tendons were measured 2, 3 and 4 weeks after the surgical repair and were analyzed statistically. The strength of the two repair methods was not statistically different 2 weeks after surgery. The tendons repaired with the four-strand core Kessler suture repair and three separate peripheral suture points were significantly stronger than those repaired with a two-strand core modified Kessler suture and a circle loop repair at 3 weeks (P = 0.033) and 4 weeks (P = 0.039). The four-strand repair with three separate peripheral suture points had greater strength than a two-strand repair with one circle loop suture based on an in vivo chicken flexor tendon model.

Toxicity of Melaleuca alternifolia essential oil to the mitochondrion and NAD+/NADH dehydrogenase in Tribolium confusum

BACKGROUND

In our previous study, Melaleuca alternifolia essential oil (EO) was considered to have an insecticidal effect by acting on the mitochondrial respiratory chain in insects. However, the mode of action is not fully understood.

METHODS

In this study, we investigated the insecticidal efficacy of the M. alternifolia EO against another major stored-product pest, Tribolium confusum Jacquelin du Val. Rarefaction and vacuolization of the mitochondrial matrix were evident in oil-fumigated T. confusum adults.

RESULTS

Alterations to the mitochondria confirmed the insecticidal effect of the M. alternifolia EO. Furthermore, comparative transcriptome analysis of T. confusum using RNA-seq indicated that most of the differentially expressed genes were involved in insecticide detoxification and mitochondrial function. The biochemical analysis showed that the intracellular NAD+/NADH ratio is involved in the differential effect of the M. alternifolia EO.

DISCUSSION

These results led us to conclude that NAD+/NADH dehydrogenase may be the prime target site for the M. alternifolia EO in insects, leading to blocking of the mitochondrial respiratory chain.

Comparative mitogenome analysis on species of four apple snails (Ampullariidae: Pomacea)

The genus Pomacea contains most of the economically important Ampullariid apple snails. Five Pomacea species were reported introduced out of their native ranges, including three highly invasive species, i.e. P. maculata, P. canaliculata and an unidentified species, Pomacea sp. In this study, the mitogenome of P. maculata was determined, which carried typical gene set of metazoan mitogenomes and shared the same gene rearrangement of Ampullariidae mitogenomes. The control region of the P. maculata has a 13-bp inverted repeat unit. We compared the mitogenome of P. maculata with P. canaliculata, Pomacea sp. and the aquatic pet species, P. diffusa. The three highly invasive species showed high sequence similarity of PCGs and RNAs. atp8 and nad2 showed the lowest similarity and the highest Ka/Ks ratios, indicating that both genes have potential for studying species identification and populations genetics in apple snails. All PCGs have the Ka/Ks ratios <1, indicating the existence of purifying selection in Pomacea species. We reconstructed phylogenetic trees using 14 Caenogastropda species based on sequences of PCGs and rRNAs using Bayesian inference. Pomacea maculata grouped with other Ampullariids and was most closely related to Pomacea sp. The mitogenome of P. maculata provides useful genetic resource for exploring the genetics and evolution of P. maculata and other apple snails.

Distribution and the origin of invasive apple snails, Pomacea canaliculata and P. maculata (Gastropoda: Ampullariidae) in China

Species of Pomacea, commonly known as apple snails, are native to South America, and have become widely distributed agricultural and environmental pests in southern China since their introduction in the 1980s. However, only since 2010 have researchers recognized that at least two species, P. canaliculata and P. maculata, are present in China. Although impacts of apple snails have been extensively documented, confusion still persists regarding current distributions and origin of the species in China. To resolve this confusion, we used phylogenetic and phylogeographic methods to analyze 1464 mitochondrial COI sequences, including 349 new sequences from samples collected in southern China and 1115 publicly available sequences from snails collected in the native and introduced ranges. Pomacea canaliculata was found at all sampled localities, while P. maculata was found at only five sampled localities in the Sichuan basin and Zhejiang province. Our data indicate that Chinese populations of P. canaliculata share an Argentinian origin, consistent with multiple introductions of this species elsewhere in Asia. In addition, just a single lineage ofP. maculata is established in China, which shares with populations in Brazil.

Asymmetric [4+2] annulations to construct norcamphor scaffolds with 2-cyclopentenone via double amine–thiol catalysis

A double catalytic system combining chiral amine and 2-mercaptobenzoic acid is applied for α′,β-regioselective [4+2] annulations of 2-cyclopentenone with diverse activated alkenes.

Empathy skill-dependent modulation of working memory by painful scene

As an important online information retaining and processing function, working memory plays critical roles in many other cognitive functions. Several long-term factors, such as age, addiction and diseases, have been affirmed to impair working memory, but whether or how the short-term factors, like painful stimuli or emotions, regulate the human working memory ability is not well explored. Here we investigated the influences of empathic pain on upcoming working memory and existing working memory, by presenting human subjects with the pictures depicting painful or neutral scene. After separating the subjects into two groups, the more empathic group and relatively indifferent group, according to a well-accepted questionnaire (the Interpersonal Reactivity Index (IRI)), the modulatory effect emerged. Empathic pain might exerted either a facilitating effect or an impairing effect, which was closely correlated with the personal empathy skills. Meanwhile, different aspects of subjects’ empathy traits exerted distinct effects, and female subjects were more vulnerable than male subjects. Present study reveals a new modulatory manner of the working memory, via empathy skill-dependent painful experience.

[Application of ultrasound guidance for fascia iliaca compartment block in pediatric femoral surgery]

Objective: To evaluate the efficacy of ultrasound guidance for fascia iliaca compartment block in pediatric femoral surgery. Methods: This study was a prospective study, thirty children who were American Society of Anesthesiologists (ASA) statusⅠ with 5-10 years old scheduled for femoral surgery were selected in orthopedics department in Second Affiliated Hospital of Wenzhou Medical University from May to December in 2014. After induction of general anesthesia, all the children were inserted the laryngeal mask. Then they were received fascia iliaca compartment block using ultrasound guidance under sevoflurane inhalation anesthesia. The indicators including heart rate(HR), mean arterial pressure(MAP), oxygen saturation(SpO(2)) and exhaled sevoflurane concentration were recorded before skin incision(T(1)), at 1, 5, 10 min after incision(T(2)-T(4))and at the end of the surgery(T(5)). Postoperative pain were assessed using the pain behavior assessment scale at awake time, 2 h and 4 h after surgery. The efficacy of postoperative analgesia and the satisfaction of parents at 2 h and 4 h after surgery were recorded. Results: The differences between HR、MAP and SpO(2) in children at T(1)-T(5) were no statistical significance (all P>0.05). Exhaled sevoflurane concentration at T(1)-T(5) were(2.50±0.51)%, (2.51±0.42)%, (2.50±0.41)%, (2.54±0.31)% and(0.61±0.20)%, respectively, the differences were statistically significant(F=13.503, P<0.05), among them that at T(5) was significantly lower than at T(1)-T(4)(all P<0.05). The pain score at awake time, 2 h and 4 h after surgery were (1.6±0.7), (3.3±1.4) and (3.9±1.3) scores, respectively. The parents satisfaction were 87% and 73% at 2 h and 4 h afer surgery respectively. Conclusion: The way of ultrasound guidance for fascia iliaca compartment block combined with general anesthesia can be safely and effectively used in pediatric femoral surgery. Using the technique of ultrasonic imaging, the fascia iliaca compartment can be directly observed and then the local anesthetics is injected, therefore the efficacy of block is improved.

Dietary intake of magnesium-l-threonate alleviates memory deficits induced by developmental lead exposure in rats

Elevation of brain magnesium enhances cognitive capacity.