Epigenetic therapy inhibits metastases by disrupting premetastatic niches.

Cancer recurrence after surgery remains an unresolved clinical problem1-3. Myeloid cells derived from bone marrow contribute to the formation of the premetastatic microenvironment, which is required for disseminating tumour cells to engraft distant sites4-6. There are currently no effective interventions that prevent the formation of the premetastatic microenvironment6,7. Here we show that, after surgical removal of primary lung, breast and oesophageal cancers, low-dose adjuvant epigenetic therapy disrupts the premetastatic microenvironment and inhibits both the formation and growth of lung metastases through its selective effect on myeloid-derived suppressor cells (MDSCs). In mouse models of pulmonary metastases, MDSCs are key factors in the formation of the premetastatic microenvironment after resection of primary tumours. Adjuvant epigenetic therapy that uses low-dose DNA methyltransferase and histone deacetylase inhibitors, 5-azacytidine and entinostat, disrupts the premetastatic niche by inhibiting the trafficking of MDSCs through the downregulation of CCR2 and CXCR2, and by promoting MDSC differentiation into a more-interstitial macrophage-like phenotype. A decreased accumulation of MDSCs in the premetastatic lung produces longer periods of disease-free survival and increased overall survival, compared with chemotherapy. Our data demonstrate that, even after removal of the primary tumour, MDSCs contribute to the development of premetastatic niches and settlement of residual tumour cells. A combination of low-dose adjuvant epigenetic modifiers that disrupts this premetastatic microenvironment and inhibits metastases may permit an adjuvant approach to cancer therapy.

Prenatal inflammation exposure accelerates lung cancer tumorigenesis in offspring mouse: possible links to IRE1α/XBP1-mediated M2-like polarization of TAMs and PD-L1 up-expression.

BACKGROUND: Prenatal inflammation exposure (PIE) can increase the disease susceptibility in offspring such as lung cancer. Our purpose was to investigate the mechanisms of PIE on lung cancer. METHODS: Prenatal BALB/c mice were exposed to lipopolysaccharide (LPS), and then, their offspring were intraperitoneally instilled with urethane to establish the two-stage lung cancer carcinogenesis model. At the 48 weeks of age, the offspring mice were killed and lung tissues were collected for HE, immunohistochemistry, immunofluorescence, and Luminex MAGPIX®-based assays. CD11b + F4/80 + tumor-associated macrophages (TAMs) were sorted out from lung tumor tissues by cell sorting technique. Flow cytometry was employed to evaluate the extent of M2-like polarization of TAMs and PD-L1 expression. RESULTS: The offspring of PIE mice revealed more lung lesion changes, including atypical hyperplasia and intrapulmonary metastases. The number of lung nodules, lung organ index, and PCNA, MMP-9 and Vimentin positive cells in lung tissue of PIE group were higher than those of Control group. The increases of mRNA encoding M2 macrophage markers and cytokines in offspring of prenatal LPS-treated mice confirmed the induced effect of PIE on macrophage polarization. Additionally, PIE treatment increased the percentage of CD163 + CD206 + cells in the sorted TAMs. Importantly, endoplasmic reticulum (ER) stress-markers like GRP78/BIP and CHOP, p-IRE1α and XBP1s, and PD-L1 were up-regulated in TAMs from PIE group. Besides, we also observed that IRE1α inhibitor (KIRA6) reversed the M2-like TAMs polarization and metastasis induced by PIE. CONCLUSIONS: IRE1α/XBP1-mediated M2-like TAMs polarization releases the pro-tumorigenic cytokines and PD-L1 expression, which may be the regulatory mechanism of accelerating lung cancer in offspring of mice undergoing PIE.

Tetraspanin CD82 Correlates with and May Regulate S100A7 Expression in Oral Cancer.

Many metastatic cancers with poor prognoses correlate to downregulated CD82, but exceptions exist. Understanding the context of this correlation is essential to CD82 as a prognostic biomarker and therapeutic target. Oral squamous cell carcinoma (OSCC) constitutes over 90% of oral cancer. We aimed to uncover the function and mechanism of CD82 in OSCC. We investigated CD82 in human OSCC cell lines, tissues, and healthy controls using the CRISPR-Cas9 gene knockout, transcriptomics, proteomics, etc. CD82 expression is elevated in CAL 27 cells. Knockout CD82 altered over 300 genes and proteins and inhibited cell migration. Furthermore, CD82 expression correlates with S100 proteins in CAL 27, CD82KO, SCC-25, and S-G cells and some OSCC tissues. The 37-50 kDa CD82 protein in CAL 27 cells is upregulated, glycosylated, and truncated. CD82 correlates with S100 proteins and may regulate their expression and cell migration. The truncated CD82 explains the invasive metastasis and poor outcome of the CAL 27 donor. OSCC with upregulated truncated CD82 and S100A7 may represent a distinct subtype with a poor prognosis. Differing alternatives from wild-type CD82 may elucidate the contradictory functions and pave the way for CD82 as a prognostic biomarker and therapeutic target.

Enhanced Selectivity in 4-Quinolone Formation: A Dual-Base System for Palladium-Catalyzed Carbonylative Cyclization with Fe(CO)5.

The use of gaseous CO in Pd-catalyzed carbonylative quinolone synthesis presents challenges related to safety and precise pressure control. In response, a streamlined non-gaseous synthesis of 4-quinolone compounds has been developed. This study introduces a tunable CO-releasing system utilizing Fe(CO)5 activated by a dual-base system of piperazine and triethylamine. This alternative liquid CO resource facilitates the palladium-catalyzed carbonylative C-C coupling and subsequent intramolecular cyclization. By tuning the tandem kinetics of carbonylation and cyclization, this non-gaseous method achieves the successful synthesis of 22 distinct 4-quinolones with excellent yields. This is achieved through the three-component condensation of sub-stoichiometric amounts of Fe(CO)5 with 2-iodoaniline and terminal alkynes. Operando mechanistic studies have revealed a novel CO transfer mechanism that facilitates homogeneous carbonylative cyclization, distinguishing this method from traditional techniques. In addition to addressing safety concerns, this approach also provides precise control over selectivity, with significant implications for pharmaceutical research and the efficient synthesis of pharmaceutical and bioactive compounds.

A General Synthesis of Cross-Conjugated Enynones through Pd Catalyzed Sonogashira Coupling with Triazine Esters.

The palladium-catalyzed Sonogashira coupling of α, ß-unsaturated acid derivatives offers a diversity-oriented synthetic strategy for cross-conjugated enynones. However, the susceptibility of the unsaturated C-C bonds adjacent to the carbonyl group toward Pd catalysts makes the direct conversion of α, ß-unsaturated derivatives as acyl electrophiles to cross-conjugated ketones rare. This work presents a highly selective C-O activation approach to prepare cross-conjugated enynones using α, ß-unsaturated triazine esters as acyl electrophiles. Under base and phosphine ligand-free conditions, NHC-Pd(II)-Allyl precatalyst alone catalyzed the cross-coupling of α, ß-unsaturated triazine esters with terminal alkynes efficiently, yielding 31 cross-conjugated enynones with diverse functional groups. This method demonstrates the potential of triazine-mediated C-O activation for preparing highly functionalized ketones.

Synthesis and Characterization of [Fe3 (As3 )3 (As4 )]3- , a Binary Fe/As Zintl Cluster With an Fe3 Core.

We report here the synthesis and structural characterization of the first binary iron arsenide cluster anion, [Fe3 (As3 )3 (As4 )]3- , present in both [K([2.2.2]crypt)]3 [Fe3 (As3 )3 (As4 )] (1) and [K(18-crown-6)]3 [Fe3 (As3 )3 (As4 )]⋅en (2). The cluster contains an Fe3 triangle with three short Fe-Fe bond lengths (2.494(1) Å, 2.459(1) Šand 2.668(2) Šfor 1, 2.471(1) Å, 2.473(1) Šand 2.660(1) Šfor 2), bridged by a 2-butene-like As4 unit. An analysis of the electronic structure using DFT reveals a triplet ground state with direct Fe-Fe bonds stabilizing the Fe3 core.

Synthesis and Characterization of Ternary Clusters Containing the [As16]10- Anion, [MM'As16]4- (M = Nb or Ta; M' = Cu or Ag).

The [Nb@As8]3- anion was first isolated from solution in 1986, and a number of isostructural [M@Pn8]n- clusters (M = Nb, Cr, or Mo; Pn = As or Sb; n = 2 or 3) have since been reported. We show here how anions of this class can be used as synthetic precursors that, in combination with sources of low-valent late transition metals (Cu and Ag), generate ternary polyarsenide cluster anions with unprecedented structural motifs. Chain type [MM'As16]4- (M = Nb or Ta; M' = Cu or Ag) units are found in compounds 2-5. These clusters contain a nortricyclane-like As7 cage and a [M@As8] crown, linked by a single As atom, and represent a fusion of two quite distinct branches of polyarsenide chemistry. Our analysis of the electronic structure confirms that the cluster retains many of the features of the component units. Electrospray ionization mass spectrometry reveals a series of smaller component ions containing 8-12 As atoms, the density functional theory-computed structures of which can be understood in terms of the pseudoelement concept. This work not only presents a new type of coordination mode for As clusters but also offers a point of entry for the rational design of multinary arsenic-based materials.

Fast and Robust Visual Tracking with Few-Iteration Meta-Learning.

Visual object tracking has been a major research topic in the field of computer vision for many years. Object tracking aims to identify and localize objects of interest in subsequent frames, given the bounding box of the first frame. In addition, the object-tracking algorithms are also required to have robustness and real-time performance. These requirements create some unique challenges, which can easily become overfitting if given a very small training dataset of objects during offline training. On the other hand, if there are too many iterations in the model-optimization process during offline training or in the model-update process during online tracking, it will cause the problem of poor real-time performance. We address these problems by introducing a meta-learning method based on fast optimization. Our proposed tracking architecture mainly contains two parts, one is the base learner and the other is the meta learner. The base learner is primarily a target and background classifier, in addition, there is an object bounding box prediction regression network. The primary goal of a meta learner based on the transformer is to learn the representations used by the classifier. The accuracy of our proposed algorithm on OTB2015 and LaSOT is 0.930 and 0.688, respectively. Moreover, it performs well on VOT2018 and GOT-10k datasets. Combined with the comparative experiments on real-time performance, our algorithm is fast and robust.

Crucial Roles of a Pendant Imidazole Ligand of a Cobalt Porphyrin Complex in the Stoichiometric and Catalytic Reduction of Dioxygen.

A cobalt porphyrin complex with a pendant imidazole base ([(L1 )CoII ]) is an efficient catalyst for the homogeneous catalytic two-electron reduction of dioxygen by 1,1'-dimethylferrocene (Me2 Fc) in the presence of triflic acid (HOTf), as compared with a cobalt porphyrin complex without a pendant imidazole base ([(L2 )CoII ]). The pendant imidazole ligand plays a crucial role not only to provide an imidazolinium proton for proton-coupled electron transfer (PCET) from [(L1 )CoII ] to O2 in the presence of HOTf but also to facilitate electron transfer (ET) from [(L1 )CoII ] to O2 in the absence of HOTf. The kinetics analysis and the detection of intermediates in the stoichiometric and catalytic reduction of O2 have provided clues to clarify the crucial roles of the pendant imidazole ligand of [(L1 )CoII ] for the first time.

Coassembly Behavior and Rheological Properties of a ß-Hairpin Peptide with Dicarboxylates.

To understand the molecular interaction mechanism and develop peptide-based hydrogels, a ß-hairpin peptide CBHH was used as the model peptide, and its coassembly performance with succinic, malic, and tartaric dicarboxylates has been investigated with circular dichroism spectroscopy (CD) and atomic force microscopy (AFM). The rheological properties and cell culture performance of the coassembled hydrogels have also been assessed. The results showed that the dicarboxylates could induce the folding and self-assembly of the ß-hairpin peptide and promote its gelation at low pH. The effects of the dicarboxylates on peptide self-assembly and hydrogel properties were correlated to their hydroxyl group number. The toxicity of the hydrogel has been assessed with NIH-3T3 cells by MTT and Calcein-AM/PI experiments, and it was confirmed that the hydrogel was biocompatible and could be used as cell culture scaffolds. We hope that this study would provide a novel way for biomaterial fabrication in cell and tissue engineering.

Impact of simulated acid rain on the composition of soil microbial communities and soil respiration in typical subtropical forests in Southwest China.

The relationship between soil respiration (SR) and microbial community structure (MCS) is relevant to changes in forest soil ecosystem stability and chemical cycling under acid rain. Simulated acid rain treatments of pH 4.5 (control), 4.0, 3.25 and 2.5 were applied to two forest stands in the Three Gorges Reservoir Area of Jinyun Mountain, Chongqing. We used phospholipid fatty acid (PLFA) analysis to observe the MCS in the 0-10 cm soil layer and measured SR in situ from January 2016 to December 2017. Additionally, we determined the effects of soil properties on the MCS and SR. Acid rain simulation significantly increased the fungal PLFA abundance and decreased the bacterial PLFA abundance in the mixed coniferous and broad-leaved forest (CF). However, in the evergreen broad-leaved forest (BF), the abundance of bacterial and fungal PLFAs did not differ significantly among treatments. Redundancy analysis (RDA) showed that significant changes in the MSC were mainly due to the C/N ratio, hydrolysable N content, content, fine root biomass and sucrase activity. Acid rain simulation in the CF and BF significantly inhibited SR, but the SR sensitivity to simulated acid rain differed among forests. In 2017, the annual mean SR in the CF under the pH 4.0, 3.25 and 2.5 treatments decreased significantly by 6.1%, 19.2% and 28.9%, but in the BF, SR decreased significantly by 25.6% only under pH 2.5. The structural equation model showed that the relationship between the MCS and the variation in SR was closer and more direct than that with soil nutrients. The microbial community structure was an important factor driving the response of soil respiration to acid rain.

Two Siblings Homozygous for F508del-CFTR Have Varied Disease Phenotypes and Protein Biomarkers.

Two siblings with CF are homozygous for F508del (referred to as Subject A and Subject B). Despite having the same CFTR genotype and similar environment, these two subjects exhibited different disease phenotypes. We analyzed their medical records and CF Foundation Registry data and measured inflammatory protein mediators in their sputum samples. Then, we examined the longitudinal relationships between inflammatory markers and disease severity for each subject and compared between them. Subject A presented a more severe disease than Subject B. During the study period, Subject A had two pulmonary exacerbations (PEs) whereas Subject B had one mild PE. The forced expiratory volume in 1 s (FEV1, % predicted) values for Subject A were between 34-45% whereas for Subject B varied between 48-90%. Inflammatory protein mediators associated with neutrophils, Th1, Th2, and Th17 responses were elevated in sputum of Subject A compared with Subject B, and also in samples collected prior to and during PEs for both subjects. Neutrophilic elastase (NE) seemed to be the most informative biomarkers. The infectious burden between these two subjects was different.

[Study on PET/CT Service Life Based on Key Components].

In this study, through the analysis of the composition of domestic large radioactive medical equipment PET/CT and the characteristics of each subsystem, combing the vulnerable spots, according to the standard requirements of PET/CT for 10 years in its service life, we research the PET/CT service life's effectiveness. Firstly, this study introduces the concept of service life, the relationship between service life and risk analysis, the pivotal system composition of PET/CT, the importance of reliability of each component, the traditional test method to verify its reliability is researched. This study suggests a test procedure and method to prove the reliability of various components of PET/CT equipment during the service life. This method is described in detail, and the specific test process in practical engineering application is discussed, which proves that it is beneficial to ensure the effectiveness of PET/CT during the service life.

[Comparison Study between the Second and First Editions of ISO/ TS 10974-Assessment of the Safety of Magnetic Resonance Imaging for Patients with an Active Implantable Medical Device].

ISO/TS 10974 is a general international technical specification (TS) which concentrates on the safety assessment of magnetic resonance imaging (MRI) for active implantable medical devices. ISO/TS 10974 Ed.2 was published in 2018 with substantial revision to Ed.1. To provide a guideline for adopting this recently revised TS in practice, this paper summarized the major changes and analyzed the technical improvements in Ed.2. Moreover, we also discussed current and emerging challenges to MRI safety evaluation remaining in Ed.2. The study revealed the consistency between these two editions with respect to classification of potential patient hazards and testing strategies, whereas Ed.2 has many methodological improvements over Ed.1 in testing methods for RF-induced heating, gradient-induced malfunction, and combined field testing, etc. However, it is still necessary to expand the scope of applicability and to adopt latest research findings into this TS to keep pace with the rapid developments in industry, making it a better guidance in the future.

[Research on Reliability Design and Verification of CT Based on Clinical Application Data].

Based on the clinical application data of medical X-ray computed tomography (CT) in the Shanghai Sixth People's Hospital, this study transformed it into the product reliability index requirements, and took the mechanical representative component-examination table (hereinafter referred to as "patient table") and the electronic representative component-DCB (data control board) as examples. Based on the relationship between failure characteristics and clinical application data, a complete set of closed-loop implementation methods from reliability index requirements to reliability design and verification are discussed.

[Research on Reliability Index and Realization of Magnetic Resonance (MR) Based on Clinical Use Condition].

Combined with the clinical use condition of MR in use in Shanghai Sixth People's Hospital, MR components are divided into scanning type I and scanning type II. At the same time, combined with the main loss force of MR components, the research divides MR components into dynamic components and electric thermal components. In this study, a complete set of MR system reliability indexes and implementation methods are given, including system reliability index determination, system reliability allocation, component reliability index realization, system reliability prediction and system reliability verification. At the same time, this study also gives the methods of reliability prediction and reliability verification, and gives the MTBF calculation method of MR system based on clinical use data statistics.

Functions and regulatory framework of ZmNST3 in maize under lodging and drought stress.

The growth and development of maize are negatively affected by various abiotic stresses including drought, high salinity, extreme temperature, and strong wind. Therefore, it is important to understand the molecular mechanisms underlying abiotic stress resistance in maize. In the present work, we identified that a novel NAC transcriptional factor, ZmNST3, enhances maize lodging resistance and drought stress tolerance. ChIP-Seq and expression of target genes analysis showed that ZmNST3 could directly regulate the expression of genes related to cell wall biosynthesis which could subsequently enhance lodging resistance. Furthermore, we also demonstrated that ZmNST3 affected the expression of genes related to the synthesis of antioxidant enzyme secondary metabolites that could enhance drought resistance. More importantly, we are the first to report that ZmNST3 directly binds to the promoters of CESA5 and Dynamin-Related Proteins2A (DRP2A) and activates the expression of genes related to secondary cell wall cellulose biosynthesis. Additionally, we revealed that ZmNST3 directly binds to the promoters of GST/GlnRS and activates genes which could enhance the production of antioxidant enzymes in vivo. Overall, our work contributes to a comprehensive understanding of the regulatory network of ZmNST3 in regulating maize lodging and drought stress resistance.

Urban-Rural Differences in Bone Mineral Density and its Association with Reproductive and Menstrual Factors Among Older Women.

PURPOSE: This study aimed to compare the bone mineral density (BMD) of older women living in rural and urban areas, and evaluate the potential factors affecting the risk of osteoporosis. METHODS: We recruited 574 women aged 65 years or older from rural areas and 496 from urban areas in Shanghai, China. The BMD values of the lumbar vertebrae and total left hip were measured by a dual energy X-ray absorptiometry densitometer. We also recorded information about education level, family income, medications, reproductive and menstrual history, diet, smoking, and alcohol consumption. RESULTS: Women in urban areas had significantly higher BMD in their lumbar spine, and there was a dramatic increase in the proportion of women with osteoporosis in rural areas. The age at menarche was significantly higher among women living in rural areas, and there were more years from menarche to menopause among urban women. Rural women had significantly higher numbers of both pregnancies and parity, and a significantly lower age at first parity. In multiple linear regression analyses, years from menarche to menopause was independently related to high lumbar spine BMD, while age at menarche and parity was independently related to low lumbar spine BMD. CONCLUSION: More older women in rural areas had osteoporosis. Later menarche, less years from menarche to menopause and higher parity might partially contribute to decreased BMD among women in rural areas. More attention should be paid to women in rural areas to prevent bone loss and further bone and health impairment.

[Study on Electromagnetic Interference Risk of Active Implantable Medical Devices in Multiple Unit Environment].

Concerning on the safety risks caused by electromagnetic interference of patients implanted with high-risk active implantable medical devices in the environment of domestic MUs, this study evaluates and focuses on the requirements of electromagnetic compatibility in domestic and international standards for rail transit vehicles, the main mechanism of risks caused by EMI, the actual measurement of environmental data in MUs and the working performance of various active implantables in the compartment. The test results shows that all kinds of active implantable medical device samples works normally in the CRH2A EMU in China, and there is still a large margin between the measured radiation emission in MU and the limit required by the standards.

[Research on Mathematical Distribution of Failure Time and Engineering Evaluation for Medical Electrical Equipment Based on Operation and Maintenance Data].

This study mainly discusses the contents, methods and characteristics of the collection of operation and maintenance data, as well as the establishment and evaluation methods of the distribution model of the failure time of medical electrical equipment. The distribution models of failure time at three levels of medical electrical equipment are established by linear regression method and goodness of fit test:The first is the device level MTBF distribution model, the second is the failure rate distribution model of the failure mode of key components, the third is the calculation model of the influence coefficient of influence factor on the failure mode of key components. This study presents a method of establishing MTBF segment model and implements a calculation model of influence coefficient varying with time.