LepR+ niche cell-derived AREG compromises hematopoietic stem cell maintenance under conditions of DNA repair deficiency and aging.

The cross talk between extrinsic niche-derived and intrinsic hematopoietic stem cell (HSC) factors controlling HSC maintenance remains elusive. Here, we demonstrated that amphiregulin (AREG) from bone marrow (BM) leptin receptor (LepR+) niche cells is an important factor that mediates the cross talk between the BM niche and HSCs in stem cell maintenance. Mice deficient of the DNA repair gene Brca2, specifically in LepR+ cells (LepR-Cre;Brca2fl/fl), exhibited increased frequencies of total and myeloid-biased HSCs. Furthermore, HSCs from LepR-Cre;Brca2fl/fl mice showed compromised repopulation, increased expansion of donor-derived, myeloid-biased HSCs, and increased myeloid output. Brca2-deficient BM LepR+ cells exhibited persistent DNA damage-inducible overproduction of AREG. Ex vivo treatment of wild-type HSCs or systemic treatment of C57BL/6 mice with recombinant AREG impaired repopulation, leading to HSC exhaustion. Conversely, inhibition of AREG by an anti-AREG-neutralizing antibody or deletion of the Areg gene in LepR-Cre;Brca2fl/fl mice rescued HSC defects caused by AREG. Mechanistically, AREG activated the phosphoinositide 3-kinases (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway, promoted HSC cycling, and compromised HSC quiescence. Finally, we demonstrated that BM LepR+ niche cells from other DNA repair-deficient and aged mice also showed persistent DNA damage-associated overexpression of AREG, which exerts similar negative effects on HSC maintenance. Therefore, we identified an important factor that regulates HSCs function under conditions of DNA repair deficiency and aging.

DNA Reaction Circuits to Establish Designated Biological Functions in Multicellular Community.

In multicellular organisms, individual cells are coordinated through complex communication networks to accomplish various physiological tasks. Aiming to establish new biological functions in the multicellular community, we used DNA as the building block to develop a cascade of nongenetic reaction circuits to establish a dynamic cell-cell communication network. Utilizing membrane-anchored amphiphilic DNA tetrahedra (TDN) as the nanoscaffold, reaction circuits were incorporated into three unrelated cells in order to uniquely regulate their sense-and-response behaviors. As a proof-of-concept, this step enabled these cells to simulate significant biological events involved in T cell-mediated anticancer immunity. Such events included cancer-associated antigen recognition and the presentation of antigen-presenting cells (APCs), APC-facilitated T cell activation and dissociation, and T cell-mediated cancer targeting and killing. By combining the excellent programmability and molecular recognition ability of DNA, our cell-surface reaction circuits hold promise for mimicking and manipulating many biological processes.

Oral contraceptives (OCs) in combination with metformin versus OCs alone on metabolism in nonobese polycystic ovary syndrome: A meta-analysis and systematic review of randomized controlled trials.

BACKGROUND: To compare OCs(oral contraceptives) + metformin and OCs alone for metabolic effects in nonobese polycystic ovary syndrome (PCOS) patients. METHODS: The search was performed in PubMed, EMBASE, the Cochrane Library and clinicaltrials.gov for all published studies up to 30 April 2022 and was limited to English-language articles. All randomized controlled trials (RCTs) comparing OCs + metformin and OCs alone for reproductive-age women with PCOS were included. Data were processed using Revman 5.3 software. RESULTS: Of 396 studies identified, 14 RCTs were included for analysis comprising 707 women. OCs+metformin significantly modified fasting glucose (MD = -0.21 [95% confidence interval (CI) = -0.31, -0.12], p < .00001) and fasting insulin (MD = -2.54 [95%CI = -4.04, -1.04], p = .0009) at study completion compared with OCs alone in nonobese PCOS subjects. There was no statistic difference in the homoeostasis model assessment of insulin resistance (HOMA-IR), high-density lipoprotein (HDL), low-density lipoprotein (LDL), total cholesterol or triglycerides at study end between the two groups. CONCLUSIONS: Metformin, via its positive effects on insulin clearance, in combination with OCs, improved glucose metabolism and offered a good treatment alternative in nonobese women with PCOS.

EPSTI1 promotes monocyte adhesion to endothelial cells in vitro via upregulating VCAM-1 and ICAM-1 expression.

Atherosclerosis is a chronic inflammatory disease of arterial wall, and circulating monocyte adhesion to endothelial cells is a crucial step in the pathogenesis of atherosclerosis. Epithelial-stromal interaction 1 (EPSTI1) is a novel gene, which is dramatically induced by epithelial-stromal interaction in human breast cancer. EPSTI1 expression is not only restricted to the breast but also in other normal tissues. In this study we investigated the role of EPSTI1 in monocyte-endothelial cell adhesion and its expression pattern in atherosclerotic plaques. We showed that EPSTI1 was dramatically upregulated in human and mouse atherosclerotic plaques when compared with normal arteries. In addition, the expression of EPSTI1 in endothelial cells of human and mouse atherosclerotic plaques is significantly higher than that of the normal arteries. Furthermore, we demonstrated that EPSTI1 promoted human monocytic THP-1 cell adhesion to human umbilical vein endothelial cells (HUVECs) via upregulating VCAM-1 and ICAM-1 expression in HUVECs. Treatment with LPS (100, 500, 1000 ng/mL) induced EPSTI1 expression in HUVECs at both mRNA and protein levels in a dose- and time-dependent manner. Knockdown of EPSTI1 significantly inhibited LPS-induced monocyte-endothelial cell adhesion via downregulation of VCAM-1 and ICAM-1. Moreover, we revealed that LPS induced EPSTI1 expression through p65 nuclear translocation. Thus, we conclude that EPSTI1 promotes THP-1 cell adhesion to endothelial cells by upregulating VCAM-1 and ICAM-1 expression, implying its potential role in the development of atherosclerosis.

Spatiotemporal Epidemiology of the Gonorrhea Epidemic in Relation to Neighborhood-level Structural Factors in an Eastern Province of China, 2016-2020.

Context: Gonorrhea, a highly communicable, sexually transmitted infection, remains a major public-health concern globally. In recent years, Zhejiang province, an eastern province, has had the highest incidence of gonorrhea in China. Objective: The study intended to identify the geographic distribution patterns and spaciotemporal clustering characteristics of the disease's incidence in Zhejiang between 2016 and 2020, to understand the spatial epidemiology of gonorrhea and to pinpoint the locations with relatively high risks of gonorrhea, the hotspots, which could be the key areas for disease prevention and control. Design: The research team performed a retrospective, spaciotemporal-clustering analysis of data about newly reported gonorrhea cases from January 2016 to December 2020 in Zhejiang province, using the China Information System for Disease Control and Prevention. Setting: The study took place at the Zhejiang Provincial Institute of Dermatology in Huzhou, China. Outcome Measures: The research team: (1) used the Geographic Information System software-ArcGIS 10.8 software to draw statistical maps; (2) conducted a spatial-pattern clustering analysis at the district or county level; (3) performed an autocorrelation analysis using Getis-Ord (Gi*) statistics to detect spatial patterns and the hotspots of gonorrhea incidence; and (4) used SaTScan9.7 to analyze the space-time clusters. Results: Zhejiang province reported 85 904 gonorrhea cases from 2016 to 2020, with a male to female ratio of 3.81:1. The average annual incidence rate of gonorrhea was 30.50 per 100 000 individuals in the population, ranging from 22.73 cases to 39.65 cases, and the annual incidence showed a significant downward trend over the five years (χ2 = 16.142, P < .001). The northern and central areas had a higher incidence than the southern area did. Autocorrelation analysis showed that the gonorrhea incidence had a significantly clustered distribution (Moran's I from 0.197 to 0.295, Z score from 4.749 to 6.909, P < .001). The high-high cluster areas were mainly in the urban districts of Hangzhou and some counties and districts of Jiaxing. The Gi* statistics further indicated that the hotspots of gonorrhea were mainly in Hangzhou, Jiaxing, and Huzhou. The Kuldorff's scan identified two clusters, mainly composed of 36 counties or districts in northern Zhejiang, such as Hangzhou and Jiaxing, and central Zhejiang, such as Jinhua and Shaoxing. Conclusions: The gonorrhea incidence rates in northern and central Zhejiang from 2016 to 2020 were higher than those in southern Zhejiang. An area of relatively higher risk for gonorrhea existed mainly in the urban districts of Hangzhou and some counties and districts of Jiaxing, Jinhua, and Shaoxing. In the future, the research team plans to focus on strengthening the prevention and control measures against gonorrhea in those areas.

Radar Human Activity Recognition with an Attention-Based Deep Learning Network.

Radar-based human activity recognition (HAR) provides a non-contact method for many scenarios, such as human-computer interaction, smart security, and advanced surveillance with privacy protection. Feeding radar-preprocessed micro-Doppler signals into a deep learning (DL) network is a promising approach for HAR. Conventional DL algorithms can achieve high performance in terms of accuracy, but the complex network structure causes difficulty for their real-time embedded application. In this study, an efficient network with an attention mechanism is proposed. This network decouples the Doppler and temporal features of radar preprocessed signals according to the feature representation of human activity in the time-frequency domain. The Doppler feature representation is obtained in sequence using the one-dimensional convolutional neural network (1D CNN) following the sliding window. Then, HAR is realized by inputting the Doppler features into the attention-mechanism-based long short-term memory (LSTM) as a time sequence. Moreover, the activity features are effectively enhanced using the averaged cancellation method, which improves the clutter suppression effect under the micro-motion conditions. Compared with the traditional moving target indicator (MTI), the recognition accuracy is improved by about 3.7%. Experiments based on two human activity datasets confirm the superiority of our method compared to traditional methods in terms of expressiveness and computational efficiency. Specifically, our method achieves an accuracy close to 96.9% on both datasets and has a more lightweight network structure compared to algorithms with similar recognition accuracy. The method proposed in this article has great potential for real-time embedded applications of HAR.

Aptamer-Functionalized Nanodevices for Dynamic Manipulation of Membrane Receptor Signaling in Living Cells.

The capacity to regulate the signaling amplitude of membrane receptors in a user-defined manner would open various opportunities for precise biological study and therapy. While partial agonists enabled downtuning of cellular responses, they required esoteric optimization of the ligand-receptor interface, limiting their practical applications. Herein, we developed an aptamer-functionalized, tweezer-like nanodevice to dynamically modulate the cellular behavior through control over the distance between receptors in the dimer with no need to involve complicated structural analysis. By combining a reversible conformation switch with aptamer-based molecular recognition, this nanodevice showed excellent performance on dynamic regulation of CD28 receptor-mediated T cell immunity. With the modular design, this nanodevice could be extended to dynamically modulate the activity of other membrane receptors (e.g., c-Met), expecting to offer a new paradigm for precise study and manipulation of specific molecular events in complex biological systems.

An Aptamer-Functionalized DNA Circuit to Establish an Artificial Interaction between T Cells and Cancer Cells.

Nongenetic strategies that enable control over the cell-cell interaction network would be highly desired, particularly in T cell-based cancer immunotherapy. In this work, we developed an aptamer-functionalized DNA circuit to modulate the interaction between T cells and cancer cells. This DNA circuit was composed of recognition-then-triggering and aggregation-then-activation modules. Upon recognizing target cancer cells, the triggering strand was released to induce aggregation of immune receptors on the T cell surface, leading to an enhancement of T cell activity for effective cancer eradication. Our results demonstrated the feasibility of this DNA circuit for promoting target cancer cell-directed stimulation of T cells, which, consequently, enhanced their killing effect on cancer cells. This DNA circuit, as a modular strategy to modulate intercellular interactions, could lead to a new paradigm for the development of nongenetic T cell-based immunotherapy.

Persistent DNA damage and oncogenic stress-induced Trem1 promotes leukemia in mice.

The immune receptor TREM1 (Triggering receptor expressed on myeloid cells 1) is a master regulator of inflammatory response. Compelling evidence suggests important pathological roles for TREM1 in various types of solid tumors. However, the role of TREM1 in hematologic malignancies is not known. Our previous study demonstrated that TREM1 cooperates with diminished DNA damage response to induce expansion of pre-leukemic hematopoietic stem cells (HSC) in mice deficient for the Fanconi anemia gene Fanca. Here we investigated TREM1 in leukemogenesis using mouse models of the DNA repair-deficient Fanca-/- and the oncogenic MLL-AF9 or KrasG12D. We found that Trem1 was highly expressed in preleukemic HSC and leukemia stem cells (LSC). By selective deletion of the Trem1 gene in the hematopoietic compartment, we showed that ablation of Trem1 reduced leukemogenic activity of the pre-leukemic HSC and LSC in mice. Trem1 was required for the proliferation of the pre-leukemic HSC and LSC. Further analysis revealed that Trem1 expression in preleukemic HSC and LSC was associated with persistent DNA damage, prolonged oncogenic stress, and a strong inflammatory signature. Targeting several top Trem1 inflammatory signatures inhibited the proliferation of pre-leukemic HSC and LSC. Collectively, our observations uncover previously unknown expression and function of TREM1 in malignant stem cells, and identify TREM1 as a driver of leukemogenesis.

Improved catalytic activity of a novel aspartate kinase by site-directed saturation mutagenesis.

This study aimed to improve the catalytic activity of aspartate kinase (AK), the first key rate-limiting enzyme in the aspartic acid metabolism pathway, by site-directed saturation mutagenesis, and to weaken the synergistic feedback inhibition of metabolites and analyze its mechanism using molecular dynamics simulation (MD). The key residual sites around the inhibitor lysine (Lys) were selected to construct the mutant strains. The mutant A380M with significantly increased enzyme activity was obtained through enzyme activity screening. Kinetic analysis showed that the Vmax value increased to 15.73 U/mg, which was 4.8 times higher than that of wild-type AK (WT AK) (3.28 U/mg). The Kn value decreased to 0.61 mM, which was significantly lower than that of the wild type (4.77 mM), indicating that the substrate affinity increased. The enzyme properties analysis showed that the optimum temperature of the mutant A380M increased from 26 °C to 35 °C, the optimum pH remained unchanged. The stability was determined at optimum temperature (35 °C) and optimum pH 8.0, and it decreased from 4.8 h to 2.7 h. The feedback inhibition was weakened, showing a significant activation with the highest relative enzyme activity of 123.29% (Water was used instead of inhibitor as blank control group, and the highest enzyme activity was defined as 100%). Molecular dynamics simulations showed that the distance between ATP and Asp was shortened after mutation. The binding force and interaction between AK and ATP and substrate Asp were enhanced. The distance between catalytic residues D193 and S192 and substrate Asp was shortened.

FANCD2 and HES1 suppress inflammation-induced PPARÉ£ to prevent haematopoietic stem cell exhaustion.

The Fanconi anaemia protein FANCD2 suppresses PPARƔ to maintain haematopoietic stem cell's (HSC) function; however, the underlying mechanism is not known. Here we show that FANCD2 acts in concert with the Notch target HES1 to suppress inflammation-induced PPARƔ in HSC maintenance. Loss of HES1 exacerbates FANCD2-KO HSC defects. However, deletion of HES1 does not cause more severe inflammation-mediated HSC defects in FANCD2-KO mice, indicating that both FANCD2 and HES1 are required for limiting detrimental effects of inflammation on HSCs. Further analysis shows that both FANCD2 and HES1 are required for transcriptional repression of inflammation-activated PPARg promoter. Inflammation orchestrates an overlapping transcriptional programme in HSPCs deficient for FANCD2 and HES1, featuring upregulation of genes in fatty acid oxidation (FAO) and oxidative phosphorylation. Loss of FANCD2 or HES1 augments both basal and inflammation-primed FAO. Targeted inhibition of PPARƔ or the mitochondrial carnitine palmitoyltransferase-1 (CPT1) reduces FAO and ameliorates HSC defects in inflammation-primed HSPCs deleted for FANCD2 or HES1 or both. Finally, depletion of PPARg or CPT1 restores quiescence in these mutant HSCs under inflammatory stress. Our results suggest that this novel FANCD2/HES1/PPARƔ axis may constitute a key component of immunometabolic regulation, connecting inflammation, cellular metabolism and HSC function.

Hes1 deficiency causes hematopoietic stem cell exhaustion.

The transcriptional repressor Hairy Enhancer of Split 1 (HES1) plays an essential role in the development of many organs by promoting the maintenance of stem/progenitor cells, controlling the reversibility of cellular quiescence, and regulating both cell fate decisions. Deletion of Hes1 in mice results in severe defects in multiple organs and is lethal in late embryogenesis. Here we have investigated the role of HES1 in hematopoiesis using a hematopoietic lineage-specific Hes1 knockout mouse model. We found that while Hes1 is dispensable for steady-state hematopoiesis, Hes1-deficient hematopoietic stem cells (HSCs) undergo exhaustion under replicative stress. Loss of Hes1 upregulates the expression of genes involved in PPARγ signaling and fatty acid metabolism pathways, and augments fatty acid oxidation (FAO) in Hes1 f/f Vav1Cre HSCs and progenitors. Functionally, PPARγ targeting or FAO inhibition ameliorates the repopulating defects of Hes1 f/f Vav1Cre HSCs through improving quiescence in HSCs. Lastly, transcriptome analysis reveals that disruption of Hes1 in hematopoietic lineage alters expression of genes critical to HSC function, PPARγ signaling, and fatty acid metabolism. Together, our findings identify a novel role of HES1 in regulating stress hematopoiesis and provide mechanistic insight into the function of HES1 in HSC maintenance.

LncRNA CASC2 targets CAV1 by competitively binding with microRNA-194-5p to inhibit neonatal lung injury.

Long non-coding RNAs (lncRNAs) are vital regulators of different biological processes during bronchopulmonary dysplasia (BPD). This study was conducted to probe the biological roles of lncRNA CASC2 in the pathogenesis of BPD and neonatal lung injury. Firstly, a hyperoxia-induced mouse model with BPD was established. LncRNAs with differential expression in lung tissues of normal and BPD mice were analyzed by microarray. An adenovirus vector overexpressing CASC2 was constructed and its functions on BPD symptoms in model mice were analyzed. Gain- and loss-of function studies of CASC2 were performed in a bronchial epithelial cell line BEAS-2B to determine its role in cell apoptosis and proliferation under normoxic and hyperoxic conditions. The downstream mechanical molecules of lncRNA CASC2 were predicted on bioinformatics systems and confirmed by luciferase assays. The functional interactions among lncRNA CASC2, miR-194-5p, and CAV1 in BPD were determined by rescue experiments. Consequently, lncRNA CASC2 was found to be poorly expressed in BPD mice. Besides, overexpressed CASC2 was found to relieve the symptoms of BPD in neonatal mice and suppress apoptosis as well as promote proliferation in hyperoxia-induced BEAS-2B cells. Importantly, CASC2 was found to regulate CAV1 expression by competitively binding to miR-194-5p and downregulate the activity of the TGF-ß1 signaling pathway, thereby suppressing lung injury. Either miR-194-5p upregulation or CAV1 downregulation blocked the roles of CASC2. To sum up, this study evidenced that CASC2 alleviates hyperoxia-induced lung injury in mouse and cell models with the involvement of a miR-194-5p-CAV1 crosstalk and the TGF-ß1 inactivation.

Irreversible electroporation ablation against subcutaneously implanted VX2 tumors in rabbits: findings of shearwave ultrasound elastography.

PURPOSE: This study aimed to evaluate stiffness changes of rabbit subcutaneous VX2 tumors before and after irreversible electroporation (IRE) ablationby shearwave ultrasound elastography (SWE). METHODS: IRE was performed on 20 subcutaneously implanted VX2 tumors in rabbits (R-SIVX2). Tumor stiffness was measured by SWE at different time points (before IRE,120minutes after IRE,7 days after IRE and 14 days after IRE). RESULTS: Before IRE, the mean stiffness (Emean) of tumors was (10.45 ± 1.07) KPa. 120 minutes after I RE, the Emean of tumors obviously rose to (70.53 ± 9.87) KPa. 7 days after IRE, the Emean of tumors decreased to (40.22 ± 9.01) KPa. 14 days after IRE, the Emean of tumors was (15.17 ± 1.00) KPa. A clear boundary was observed between the ablation area and the normal tissues in the pathological results. CONCLUSIONS: The stiffness of the VX2 tumors experienced a first rise process and tend to be normal in the procedure of IRE. SWE could provide tissue stiffness information of different IRE ablation period as a non-invasive method.

TM4SF19 aggravates LPS-induced attenuation of vascular endothelial cell adherens junctions by suppressing VE-cadherin expression.

Atherosclerosis is a chronic vascular inflammatory disease that initially starts from an arterial intima lesion and endothelial barrier dysfunction. The purpose of this study was to investigate the role of TM4SF19, a recently identified member of the transmembrane 4L six superfamily, in vascular endothelial cell adherens junctions. We found TM4SF19 expression was significantly increased in atherosclerotic plaques and sera of patients with coronary heart disease (CHD) compared with healthy people by immunohistochemistry and ELISA. In vitro, human umbilical vein endothelial cells (HUVECs) were stimulated by lipopolysaccharides (LPS). TM4SF19 and VE-cadherin expression as well as cell adherens junctions were assessed. Additionally, LPS could upregulate TM4SF19 expression and downregulate VE-cadherin expression in HUVECs in a concentration dependent manner. Overexpression of TM4SF19 substantially aggravated LPS-induced reduction of VE-cadherin expression and attenuation of vascular endothelial cell adherens junctions. However, both the decreased VE-cadherin expression and weakened cell adherens junctions induced by LPS could be dramatically reversed when the expression of TM4SF19 was depressed. This study is the first to reveal the effect of TM4SF19 on endothelial cell adherens junctions. Meanwhile, our results also provide novel therapeutic strategies for atherosclerotic diseases.

p53-TP53-Induced Glycolysis Regulator Mediated Glycolytic Suppression Attenuates DNA Damage and Genomic Instability in Fanconi Anemia Hematopoietic Stem Cells.

Emerging evidence has shown that resting quiescent hematopoietic stem cells (HSCs) prefer to utilize anaerobic glycolysis rather than mitochondrial respiration for energy production. Compelling evidence has also revealed that altered metabolic energetics in HSCs underlies the onset of certain blood diseases; however, the mechanisms responsible for energetic reprogramming remain elusive. We recently found that Fanconi anemia (FA) HSCs in their resting state are more dependent on mitochondrial respiration for energy metabolism than on glycolysis. In the present study, we investigated the role of deficient glycolysis in FA HSC maintenance. We observed significantly reduced glucose consumption, lactate production, and ATP production in HSCs but not in the less primitive multipotent progenitors or restricted hematopoietic progenitors of Fanca-/- and Fancc-/- mice compared with that of wild-type mice, which was associated with an overactivated p53 and TP53-induced glycolysis regulator, the TIGAR-mediated metabolic axis. We utilized Fanca-/- HSCs deficient for p53 to show that the p53-TIGAR axis suppressed glycolysis in FA HSCs, leading to enhanced pentose phosphate pathway and cellular antioxidant function and, consequently, reduced DNA damage and attenuated HSC exhaustion. Furthermore, by using Fanca-/- HSCs carrying the separation-of-function mutant p53R172P transgene that selectively impairs the p53 function in apoptosis but not cell-cycle control, we demonstrated that the cell-cycle function of p53 was not required for glycolytic suppression in FA HSCs. Finally, ectopic expression of the glycolytic rate-limiting enzyme PFKFB3 specifically antagonized p53-TIGAR-mediated metabolic reprogramming in FA HSCs. Together, our results suggest that p53-TIGAR metabolic axis-mediated glycolytic suppression may play a compensatory role in attenuating DNA damage and proliferative exhaustion in FA HSCs. Stem Cells 2019;37:937-947.

Study on Controllable Assembly of Stearic Acid within Interlayer Spacing of Montmorillonite and Its Energy Storage Performance.

As an energy carrier, the phase change material can enhance the efficiency of an energy source and reduce its load. The present paper describes the assembly of the energy carrier molecule [stearic acid (SA)] into the interlayer spacing of montmorillonite (Mt). A novel inorganic/organic composite energy storage material was prepared, which effectively reduces the phase change temperature of the energy storage molecule. Through acid treatment, the Si4+/Al3+ ratio of Mt can be regulated to obtain a series of Mts with different layer charges. As a result, a controllable assembly of energy storage molecule, SA, into the interlayer spacing of Mts with different layer charges was accomplished. By controlling the layer charges of Mt arrangement morphology and interactive force of SA molecules in the interlayer, spacing of Mt can be changed effectively. The phase change temperature (exothermic reaction) reduces from 50.5 to 32 °C compared with the SA molecules, which are used to control phase change temperature of the energy storage material. The study presents a SA/Mt energy storage material that can aid in further development in the field of energy storage construction materials.

Mesenchymal COX2-PG secretome engages NR4A-WNT signalling axis in haematopoietic progenitors to suppress anti-leukaemia immunity.

The bone marrow (BM) microenvironment (niche) plays important roles in supporting normal/abnormal haematopoiesis. We investigated the interaction between leukaemic mesenchymal niche and haematopoietic stem and progenitor cells (HSPCs) using the model of Fanconi anaemia (FA), a genetic disorder characterized by BM failure and leukaemia. Healthy donor HSPCs co-cultured on mesenchymal stromal cells (MSCs) derived from FA patients with acute myeloid leukaemia (AML) exhibited higher human engraftment and myeloid expansion in Non-obese diabetic severe combined immunodeficiency IL-2γ-/- /SGM3 recipients. Untargeted metabolomics analysis revealed the progressively elevated prostaglandins (PGs) in the MSCs of FA patients with myelodysplastic syndromes (MDS) and AML. Reduced secretion of PGs subsequent to inflammatory cyclooxygenase 2 (COX2) inhibition ameliorated HSPC/myeloid expansion. Transcriptome analysis demonstrated dysregulation of genes involved in the NR4A family of transcription factors (TFs) and WNT/ß-catenin signalling pathway in FA-AML-MSC-co-cultured-CD34+ cells. COX2 inhibition led to significantly decreased NR4A TFs and WNT signalling genes expression. Mechanistically, NR4A1 and NR4A2 synergistically activate the CTNNB1 gene promoter . Knocking down CTNNB1 or NR4A1 in AML-MSC-co-cultured-CD34+ cells increased leukaemia-reactive T-effector cells production and rescued anti-leukaemia immunity. Together, these findings suggest that specific interactions between leukaemic mesenchymal niche and HSPCs orchestrate a novel COX2/PG-NR4A/WNT signalling axis, connecting inflammation, cellular metabolism and cancer immunity.

Repetition Priming Effects in Proficient Mandarin-Cantonese and Cantonese-Mandarin Bidialectals: An Event-Related Potential Study.

The present study adopted a repetition priming paradigm to investigate the bidialectal (bilingual) representation of speakers with different native dialects by event-related potential (ERP) technique. Proficient Mandarin-Cantonese and Cantonese-Mandarin bidialectals participated in the study. They were required to judge whether a word was a biological word or not, when the words (target word) were represented under four types of repetition priming conditions: Mandarin (prime)-Mandarin (target), Mandarin (prime)-Cantonese (target), Cantonese (prime)-Cantonese (target) and Cantonese (prime)-Mandarin (target). Results of reaction time and accuracy primarily indicated larger repetition priming effects in Mandarin-Mandarin and Cantonese-Cantonese (within-language) conditions than that in Mandarin-Cantonese and Cantonese-Mandarin (between-language) conditions. But more importantly, P200 and N400 mean amplitudes revealed distinct repetition priming effects between two types of participants. Specifically, both P200 and N400 indicated that the repetition priming effect in Mandarin-Mandarin condition was larger than that in Cantonese-Cantonese condition for Mandarin-Cantonese participants, whereas it was opposite for Cantonese-Mandarin participants. In addition, P200 also suggested opposite patterns of repetition priming effects in between-language priming conditions for two groups of participants. The repetition priming effect in Mandarin-Cantonese condition was larger than that in Cantonese-Mandarin condition for Mandarin-Cantonese participants, while for Cantonese-Mandarin participants, it was opposite (Mandarin-Cantonese < Cantonese-Mandarin). The results implied a clear asymmetric representation of two dialects for proficient bidialectals. They were further discussed in light of native dialect and language use frequency.

The effects of a picosecond pulsed electric field on angiogenesis in the cervical cancer xenograft models.

OBJECTIVE: The application of picosecond pulsed electric field (psPEF) is a new biomedical engineering technique used in cancer therapy. However, its effects on cervical cancer angiogenesis are not clear. Therefore, the aim of the present study is to investigate the effects of psPEF on angiogenesis in cervical cancer xenograft models. METHODS: Xenograft tumors were created by subcutaneously inoculating nude mice (athymic BALB/c nu/nu mice) with HeLa cells, then were placed closely between tweezer-type plate electrodes and subjected to psPEF with a gradually increased electric field intensity (0kV/cm, 50kV/cm, 60kV/cm, 70kV/cm). The direct effect on tumor tissue was observed by hematoxylin and eosin (H&E) staining and transmission electron microscopy (TEM). The changes of blood vessels and oxygen saturation (sO2) of tumors were monitored in vivo by photoacoustic tomography (PAT). The microvessel density (MVD), vascular endothelial growth factor (VEGF) and hypoxia-inducible transcription factors (HIF-1α and HIF-2α) were detected by immunohistochemical technique (IHC). Their protein expressions and gene transcription levels were evaluated using western blot (WB) and quantitative reverse transcription and polymerase chain reaction (RT-PCR). RESULTS: PsPEF induced obvious necrosis of cervical cancer tissue; with the increasing of electric field intensity, the MVD, vascular PA signal and sO2 values declined significantly. The protein expression and gene transcription levels of VEGF, HIF1α and HIF2α were significantly decreased at the same time. CONCLUSION: PsPEF exhibited dramatic anti-tumor and anti-angiogenesis effects in cervical cancer xenograft models by exerting direct effect on cancer cells and vascular endothelial cells and indirect effect on tumor angiogenesis-related factors.