mDia formins form hetero-oligomers and cooperatively maintain murine hematopoiesis

mDia formin proteins regulate the dynamics and organization of the cytoskeleton through their linear actin nucleation and polymerization activities. We previously showed that mDia1 deficiency leads to aberrant innate immune activation and induces myelodysplasia in a mouse model, and mDia2 regulates enucleation and cytokinesis of erythroblasts and the engraftment of hematopoietic stem and progenitor cells (HSPCs). However, whether and how mDia formins interplay and regulate hematopoiesis under physiological and stress conditions remains unknown. Here, we found that both mDia1 and mDia2 are required for HSPC regeneration under stress, such as serial plating, aging, and reconstitution after myeloid ablation. We showed that mDia1 and mDia2 form hetero-oligomers through the interactions between mDia1 GBD-DID and mDia2 DAD domains. Double knockout of mDia1 and mDia2 in hematopoietic cells synergistically impaired the filamentous actin network and serum response factor-involved transcriptional signaling, which led to declined HSPCs, severe anemia, and significant mortality in neonates and newborn mice. Our data demonstrate the potential roles of mDia hetero-oligomerization and their non-rodent functions in the regulation of HSPCs activity and orchestration of hematopoiesis.

Clonal hematopoiesis and bone marrow inflammation

Clonal hematopoiesis (CH) occurs in hematopoietic stem cells with increased risks of progressing to hematologic malignancies. CH mutations are predominantly found in aged populations and correlate with an increased incidence of cardiovascular and other diseases. Increased lines of evidence demonstrate that CH mutations are closely related to the inflammatory bone marrow microenvironment. In this review, we summarize the recent advances in this topic starting from the discovery of CH and its mutations. We focus on the most commonly mutated and well-studied genes in CH and their contributions to the innate immune responses and inflammatory signaling, especially in the hematopoietic cells of bone marrow. We also aimed to discuss the interrelationship between inflammatory bone marrow microenvironment and CH mutations. Finally, we provide our perspectives on the challenges in the field and possible future directions to help understand the pathophysiology of CH.

High abundance of CDC45 inhibits cell proliferation through elevation of HSPA6

OBJECTIVES

CDC45 is the core component of CMG (CDC45-MCMs-GINS) complex that plays important role in the initial step of DNA replication in eukaryotic cells. The expression level of cdc45 is under the critical control for the accurate cell cycle progression. Loss-of-function of cdc45 has been demonstrated to inhibit cell proliferation and leads to cell death due to the inhibition of DNA replication and G1-phase arrest. An increasing of CDC45 inhibits cell proliferation as well. Nevertheless, a systematic analysis of the effect of high dose of CDC45 on cell physiology and behaviors is unclear. In the present study, we aimed to investigate the effects and mechanisms of high dose of CDC45 on cell behaviors.

MATERIALS AND METHODS

We overexpressed cdc45 in cultured cell lines, Ciona and Drosophila embryos, respectively. The cell cycle progression was examined by the BrdU incorporation experiment, flow cytometry and PH3 (phospho-Histone 3) staining. RNA-sequencing analysis and qRT-PCR were carried out to screen the affected genes in HeLa cells overexpressing cdc45. siRNA-mediated knockdown was performed to investigate gene functions in HeLa cells overexpressing cdc45.

RESULTS

We found that high level of cdc45 from different species (human, mammal, ascidian, and Drosophila) inhibited cell cycle in vitro and in vivo. High dose of CDC45 blocks cells entering into S phase. However, we failed to detect DNA damage and cell apoptosis. We identified hspa6 was the most upregulated gene in HeLa cells overexpressing cdc45 via RNA-seq analysis and qRT-PCR validation. Overexpression of Hs-hspa6 inhibited proliferation rate and DNA replication in HeLa cells, mimicking the phenotype of cdc45 overexpression. RNAi against hspa6 partially rescued the cell proliferation defect caused by high dose of CDC45.

CONCLUSIONS

Our study suggests that high abundance of CDC45 stops cell cycle. Instead of inducing apoptosis, excessive CDC45 prevents cell entering S phase probably due to promoting hspa6 expression.

The Lateral Epidermis Actively Counteracts Pulling by the Amnioserosa During Dorsal Closure

Dorsal closure is a prominent morphogenetic process during Drosophila embryogenesis, which involves two epithelial tissues, that is, the squamous amnioserosa and the columnar lateral epidermis. Non-muscle myosin II-driven constriction in the amnioserosa leads to a decrease in the apical surface area and pulls on the adjacent lateral epidermis, which subsequently moves dorsally. The pull by the amnioserosa becomes obvious in an elongation of the epidermal cells, especially of those in the first row. The contribution of the epidermal cell elongation has remained unclear to dorsal closure. Cell elongation may be a mere passive consequence or an active response to the pulling by the amnioserosa. Here, we found that the lateral epidermis actively responds. We analyzed tensions within tissues and cell junctions by laser ablation before and during dorsal closure, the elliptical and dorsal closure stages, respectively. Furthermore, we genetically and optochemically induced chronic and acute cell contraction, respectively. In this way, we found that tension in the epidermis increased during dorsal closure. A correspondingly increased tension was not observed at individual junctions, however. Junctional tension even decreased during dorsal closure in the epidermis. We strikingly observed a strong increase of the microtubule amount in the epidermis, while non-muscle myosin II increased in both tissues. Our data suggest that the epidermis actively antagonizes the pull from the amnioserosa during dorsal closure and the increased microtubules might help the epidermis bear part of the mechanical force.

TMB and TCR Are Correlated Indicators Predictive of the Efficacy of Neoadjuvant Chemotherapy in Breast Cancer

Immune characteristics were reported correlated to benefit neoadjuvant chemotherapy (NAC) in breast cancer, yet integration of comprehensive genomic alterations and T-cell receptors (TCR) to predict efficacy of NAC needs further investigation. This study simultaneously analyzed TMB (Tumor Mutation Burden), TCRs, and TILs (tumor infiltrating lymphocyte) in breast cancers receiving NAC was conducted in a prospective cohort (n = 22). The next-generation sequencing technology-based analysis of genomic alterations and TCR repertoire in paired breast cancer samples before and after NAC was conducted in a prospective cohort (n = 22). Fluorescent multiplex immunohistochemistry was used to stain CD4, CD8, PD1, TIM3, and cytokeratins simultaneously in those paired samples. TMB in pretreatment tumor tissues and TCR diversity index are higher in non-pCR patients than in pCR patients (10.6 vs. 2.3; p = 0.043) (2.066 vs. 0.467; p = 0.010). TMB and TCR diversity index had linear correlation (y = 5.587x − 0.881; r = 0.522, p = 0.012). Moreover, infiltrating T cells are significantly at higher presence in pCR versus non-pCR patients. Dynamically, the TMB reduced significantly after therapy in non-pCR patients (p = 0.010) but without TCR index change. The CDR3 peptide AWRSAGNYNEQF is the most highly expressed in pre-NAC samples of pCR patients and in post-NAC samples of non-pCR patients. In addition to pCR, high clonality of TCR and high level of CD8+ expression are associated with disease-free survival (DFS). TCR index and TMB have significant interaction and may guide neo-adjuvant treatment in operable breast cancers. Response to NAC in tumors with high TCR clonality may be attributable to high infiltration and expansion of tumor-specific CD8 positive effector cells.

Dia- and Rok-dependent enrichment of capping proteins in a cortical region

Rho signaling with its major targets the formin Dia, Rho kinase (Rok) and non-muscle myosin II (MyoII, encoded by zip in flies) control turnover, amount and contractility of actomyosin. Much less investigated has been a potential function for the distribution of F-actin plus and minus ends. In syncytial Drosophila embryos, Rho1 signaling is high between actin caps, i.e. the cortical intercap region. Capping protein binds to free plus ends of F-actin to prevent elongation of the filament. Capping protein has served as a marker to visualize the distribution of F-actin plus ends in cells and in vitro. In the present study, we probed the distribution of plus ends with capping protein in syncytial Drosophila embryos. We found that capping proteins are specifically enriched in the intercap region similar to Dia and MyoII but distinct from overall F-actin. The intercap enrichment of Capping protein was impaired in dia mutants and embryos, in which Rok and MyoII activation was inhibited. Our observations reveal that Dia and Rok-MyoII control Capping protein enrichment and support a model that Dia and Rok-MyoII control the organization of cortical actin cytoskeleton downstream of Rho1 signaling.

This article has an associated First Person interview with the first authors of the paper.

Summary: Plus ends of actin filaments are enriched at cortical regions rich in Rho signaling in syncytial Drosophila embryos depending on the actin regulator Dia and Rho kinase.

Catheter lock solutions for reducing catheter-related bloodstream infections in paediatric patients: a network meta-analysis

BACKGROUND

Different catheter lock solutions (CLSs) are used to reduce catheter-related bloodstream infection (CRBSI) for paediatric patients with central venous catheters (CVCs), but the most effective CLS is unknown.

AIM

To compare the effectiveness of different CLSs for the prevention of CRBSI in paediatric patients.

METHODS

Potential studies were searched and selected through the PubMed, Embase, Web of Science and Cochrane Library up to May 2021. Randomized controlled trials that assessed the effects of CLSs for preventing CRBSI in paediatric patients were included. We performed a random-effects network meta-analysis to estimate risk ratio (RR) with 95% confidence interval (CI).

FINDINGS

Thirteen studies comprising 1335 patients were included in the network meta-analysis. Taurolidine + heparin was effective in the prevention of CRBSI compared with heparin in paediatric patients (RR: 0.21, 95% CI: 0.09-0.51). No significant difference was found between the other CLSs (such as vancomycin, ethanol, fusidic acid, amikacin, and amikacin and vancomycin) and heparin or between different intervention lock solutions for CRBSI prevention. Based on the surface under the cumulative ranking curve, taurolidine + heparin (85.3%) appeared to be the most effective solution for effectiveness on CRBSI prevention, followed by fusidic acid + heparin (77.0%) and amikacin + heparin (65.7%). There was no statistical global inconsistency among the included studies after design by treatment test (χ² = 2.22, P=0.137).

CONCLUSION

The study showed that taurolidine lock solution seemed to be the most effective for the prevention of CRBSI in paediatric patients. Well-designed randomized trials in paediatric patients are needed to provide more reliable evidence in the effectiveness of different CLSs.

Worldwide cancer statistics of adolescents and young adults in 2019: a systematic analysis of the Global Burden of Disease Study 2019

Background

The cancer burden in adolescents and young adults (AYAs) deserves more attention. However, global cancer statistics for AYAs are often presented as aggregates, concealing important heterogeneity. This study aimed to describe the worldwide profile of cancer incidence, mortality, and corresponding trends from 1990 to 2019 among 15-39-year olds by focusing on the patterns by age, sex, sociodemographic index (SDI), and regions.

Patients and methods

Global, regional, and country data on the number of cancer cases and cancer-related deaths for 29 cancer types were collected from the 2019 Global Burden of Disease (GBD) Study. We also summarized the results using five levels of the SDI and 21 GBD regions.

Results

In 2019, an estimated 1 335 100 new cancer cases and 397 583 cancer-related deaths occurred among AYAs worldwide. While the incidence rate increased mildly, the death rate decreased significantly between 1990 and 2019, with an estimated annual percentage change of 0.38 (95% confidence interval 0.36-0.39) and −0.93 (95% confidence interval −0.95 to −0.92), respectively. The cancer burden was disproportionally greater among women than among men. The cancer profiles varied substantially across geographical regions, with the highest burden being in South Asia and East Asia. Besides, the cancer incidence in the high SDI regions was four times higher than that in the low SDI regions; however, the mortality burden in the high SDI region was lower than that in the low SDI region, which reflected the differences in cancer profiles across SDI regions and the inferior outcomes in the low SDI regions.

Conclusion

This study updates the previous epidemiological data of the cancer burden of AYAs. The cancer burden in AYAs varied substantially according to age, sex, SDI, and geographical regions. These findings highlight that the specific cancer profile of AYA patients requires targeted cancer control measures to reduce the cancer burden in this age group.

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The cancer burden in AYAs varied substantially according to age, sex, SDI, and geographical regions.

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Cancer burden in AYAs was disproportionally greater among women than among men.

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Cancer profiles of AYAs varied across different geographical regions and SDI regions.

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Cancer burden in AYAs was still considerable in the low SDI regions.

Analysis of long non-coding RNA expression profiles in disuse osteoporosis using microarray and bioinformatics

Disuse osteoporosis (DOP) is one of the major consequences of long space flights. DOP also occurs in patients with spinal cord injuries and prolonged bedridden states that can have a severe impact on human health. Bone marrow mesenchymal stem cells (BMSCs) are multipotent stromal cells that play an important role in bone homeostasis. Long non-coding RNAs (lncRNAs) are involved in regulating osteogenic differentiation of BMSCs, and their abnormal expression might lead to the formation of orthopedic diseases. However, the specific mechanism of DOP has not yet been elucidated. All sequencing data were obtained from Gene Expression Omnibus (GEO) datasets. The limma package of R was applied to identify DEmRNAs and DElncRNAs. Pearson correlation coefficients (PCC) between DElncRNADEmRNA expression levels were calculated. Functional annotation was performed for DEmRNAs coexpressed with DElncRNAs. In addition, the Cytohubba plug-in in Cytoscape was applied to determine the top 10 hub genes. Finally, connectivity map (CMap) analysis was used to identify potential therapeutic drugs for DOP. The gene expression data, GSE100930 and GSE17696, were retrieved from the GEO database. A total of 2,212 differentially expressed mRNAs (DEmRNAs) and 22 differentially expressed lncRNAs (DElncRNAs) were obtained. Gene ontology (GO) functional terms, Kyoto Encyclopedia of Genes, and Genomes (KEGG) pathway enrichment analysis reveal 30 significant GO terms and 13 significant pathways. A coding-non-coding gene co-expression (CNC) network was constructed to study the potential role of hub-DElncRNAs and their co-expressed DEmRNAs in DOP. The lncRNAs, GSNAS1, SNHG12, and EPB41LA4A-AS1, were significant in the CNC network and potential regulators of DOP development. Three bioactive compounds (scoulerine, kinetin riboside, dexanabinol) with potential therapeutic significance for DOP were obtained through the Connectivity Map (CMAP) analysis. Our study revealed a new mechanism for a lineage shift of bone marrow mesenchymal stem cells under microgravity, and linked the function of protein-coding mRNAs with ncRNAs, which may contribute to the development of new therapies for DOP.

Wuyiencin produced by Streptomyces albulus CK-15 displays biocontrol activities against cucumber powdery mildew

AIMS

Wuyiencin is a nucleoside antibiotic produced by Streptomyces albulus CK-15. The aim of this study was to determine whether wuyiencin can be used, as a suitable alternative to chemical pesticides, to protect cucumbers (Cucumis sativus L.) from powdery mildew caused by Sphaerotheca fuliginea. Further, the mechanisms underlying the control of cucumber powdery mildew by S. albulus CK-15 were preliminarily elucidated.

METHODS AND RESULTS

Wuyiencin solutions of different concentrations were used to treat infected cucumber plants under greenhouse conditions. The results indicated that wuyiencin could significantly reduce powdery mildew disease incidence, with a maximum prevention efficacy of 94·38%. Further, scanning electron micrographs and enzyme assays showed that wuyiencin inhibited S. fuliginea spore growth and elicited the activity of plant systemic resistance-related enzymes. Additionally, real-time quantitative reverse transcription PCR suggested that wuyiencin can activate a salicylic acid-dependent plant defence response.

CONCLUSIONS

Wuyiencin produced by S. albulus CK-15 possessed antifungal effects and was able to mitigate cucumber powdery mildew disease via antagonistic action. Wuyiencin also induced defence responses in the plants.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results reinforce the biotechnological potential of wuyiencin as both an antagonistic agent and an inducer of plant systemic resistance.

Cytoskeletal mechanics and dynamics in the Drosophila syncytial embryo

Cell and tissue functions rely on the genetic programmes and cascades of biochemical signals. It has become evident during the past decade that the physical properties of soft material that govern the mechanics of cells and tissues play an important role in cellular function and morphology. The biophysical properties of cells and tissues are determined by the cytoskeleton, consisting of dynamic networks of F-actin and microtubules, molecular motors, crosslinkers and other associated proteins, among other factors such as cell-cell interactions. The Drosophila syncytial embryo represents a simple pseudo-tissue, with its nuclei orderly embedded in a structured cytoskeletal matrix at the embryonic cortex with no physical separation by cellular membranes. Here, we review the stereotypic dynamics and regulation of the cytoskeleton in Drosophila syncytial embryos and how cytoskeletal dynamics underlies biophysical properties and the emergence of collective features. We highlight the specific features and processes of syncytial embryos and discuss the applicability of biophysical approaches.

Comparative analysis of target gene exon sequencing by cognitive technology using a next generation sequencing platform in patients with lung cancer

Next generation sequencing (NGS) technology is an increasingly important clinical tool for therapeutic decision-making. However, interpretation of NGS data presents challenges at the point of care, due to limitations in understanding the clinical importance of gene variants and efficiently translating results into actionable information for the clinician. The present study compared two approaches for annotating and reporting actionable genes and gene mutations from tumor samples: The traditional approach of manual curation, annotation and reporting using an experienced molecular tumor bioinformationist; and a cloud-based cognitive technology, with the goal to detect gene mutations of potential significance in Chinese patients with lung cancer. Data from 285 gene-targeted exon sequencing previously conducted on 115 patient tissue samples between 2014 and 2016 and subsequently manually annotated and evaluated by the Guangdong Lung Cancer Institute (GLCI) research team were analyzed by the Watson for Genomics (WfG) cognitive genomics technology. A comparative analysis of the annotation results of the two methods was conducted to identify quantitative and qualitative differences in the mutations generated. The complete congruence rate of annotation results between WfG analysis and the GLCI bioinformatician was 43.48%. In 65 (56.52%) samples, WfG analysis identified and interpreted, on average, 1.54 more mutation sites in each sample than the manual GLCI review. These mutation sites were located on 27 genes, including EP300, ARID1A, STK11 and DNMT3A. Mutations in the EP300 gene were most prevalent, and present in 30.77% samples. The Tumor Mutation Burden (TMB) interpreted by WfG analysis (1.82) was significantly higher than the TMB (0.73) interpreted by GLCI review. Compared with manual curation by a bioinformatician, WfG analysis provided comprehensive insights and additional genetic alterations to inform clinical therapeutic strategies for patients with lung cancer. These findings suggest the valuable role of cognitive computing to increase efficiency in the comprehensive detection and interpretation of genetic alterations which may inform opportunities for targeted cancer therapies.

Ciona embryonic tail bending is driven by asymmetrical notochord contractility and coordinated by epithelial proliferation

Ventral bending of the embryonic tail within the chorion is an evolutionarily conserved morphogenetic event in both invertebrates and vertebrates. However, the complexity of the anatomical structure of vertebrate embryos makes it difficult to experimentally identify the mechanisms underlying embryonic folding. This study investigated the mechanisms underlying embryonic tail bending in chordates. To further understand the mechanical role of each tissue, we also developed a physical model with experimentally measured parameters to simulate embryonic tail bending. Actomyosin asymmetrically accumulated at the ventral side of the notochord, and cell proliferation of the dorsal tail epidermis was faster than that in the ventral counterpart during embryonic tail bending. Genetic disruption of actomyosin activity and inhibition of cell proliferation dorsally caused abnormal tail bending, indicating that both asymmetrical actomyosin contractility in the notochord and the discrepancy of epidermis cell proliferation are required for tail bending. In addition, asymmetrical notochord contractility was sufficient to drive embryonic tail bending, whereas differential epidermis proliferation was a passive response to mechanical forces. These findings showed that asymmetrical notochord contractility coordinates with differential epidermis proliferation mechanisms to drive embryonic tail bending.

This article has an associated ‘The people behind the papers’ interview.

Quantitative multiplex immunofluorescence analysis identifies infiltrating PD1+ CD8+ and CD8+ T cells as predictive of response to neoadjuvant chemotherapy in breast cancer

Background

This study aimed to explore the potentially predictive role and dynamic changes of immune checkpoints on T cell subsets in patients with breast cancer receiving neoadjuvant chemotherapies.

Methods

Fluorescent multiplex immunohistochemistry (mIHC) was used to stain CD4, CD8, PD1, TIM3, and cytokeratins simultaneously in paired breast cancer samples before and after neoadjuvant therapies (NAT) in a prospective cohort (n = 50). Singleplex IHC was conducted to stain for CD3 in 100 cases with inclusion of extra retrospective 50 cases. Cell levels were correlated with clinicopathological parameters and pathological complete response (pCR).

Results

In pretreatment tumors, the percentages of infiltrating CD8⁺, PD1⁺, PD1⁺CD8⁺, and the ratio of PD1⁺CD8⁺/CD8⁺ cells, were higher in pCR than non‐pCR patients in either the stromal or intratumoral area, but PD1⁺CD4⁺, TIM3⁺CD4⁺, TIM3⁺CD8⁺ cells and CD4⁺/CD8⁺ ratio was not. Multivariate analyses showed that the percentage of intratumoral CD8⁺ cells (OR, 1.712; 95% CI: 1.052–2.786; P = 0.030) and stromal PD1⁺CD8⁺/CD8⁺ ratio (OR, 1.109; 95% CI: 1.009–1.218; P = 0.032) were significantly associated with pCR. Dynamically, reduction in the percentages of PD1⁺, CD8⁺ and PD1⁺CD8⁺ cells after therapy strongly correlated with pCR. Notably, incremental percentages of PD1⁺CD8⁺ cells, rather than TIM3⁺CD8⁺, were shown in tumors from non‐pCR patients after NAT. CD3 staining confirmed the percentage of T cells were associated with pCR.

Conclusions

PD1⁺CD8⁺ rather than TIM3⁺CD8⁺ cells are main predictive components within tumor‐infiltrating T cells in NAT breast cancer patients. Dynamically incremental levels of PD1⁺CD8⁺ cells occurred in non‐pCR cases after NAT, suggesting the combination of chemotherapy with PD1 inhibition might benefit these patients.

Key points

Significant findings of the study

PD1⁺CD8⁺, rather than TIM3⁺CD8⁺, T cells are the main component to predict the response of neoadjuvant therapies in breast cancer.

What this study adds

Incremental levels of PD1⁺CD8⁺ T cells in non‐pCR post‐NAT tumors suggest PD1 inhibition might benefit in the neoadjuvant setting.

Viral Load Dynamics in Sputum and Nasopharyngeal Swab in Patients with COVID-19

Coronavirus disease 2019 (COVID-19) has caused a global pandemic associated with substantial morbidity and mortality. Nasopharyngeal swabs and sputum samples are generally collected for serial viral load screening of respiratory contagions, but temporal profiles of these samples are not completely clear in patients with COVID-19. We performed an observational cohort study at Renmin Hospital of Wuhan University, which involved 31 patients with confirmed COVID-19 with or without underlying diseases. We obtained samples from each patient, and serial viral load was measured by real-time quantitative polymerase chain reaction. We found that the viral load in the sputum was inclined to be higher than samples obtained from the nasopharyngeal swab at disease presentation. Moreover, the viral load in the sputum decreased more slowly over time than in the nasopharyngeal group as the disease progressed. Interestingly, even when samples in the nasopharyngeal swab turned negative, it was commonly observed that patients with underlying diseases, especially hypertension and diabetes, remained positive for COVID-19 and required a longer period for the sputum samples to turn negative. These combined findings emphasize the importance of tracking sputum samples even in patients with negative tests from nasopharyngeal swabs, especially for those with underlying conditions. In conclusion, this work reinforces the importance of sputum samples for SARS-CoV-2 detection to minimize transmission of COVID-19 within the community.

Predicting pungency and understanding the pungency mechanism of capsaicinoids using TOPS-MODE approach

Quantitative structure-property relationship (QSPR) models were developed for predicting the pungency of a set of capsaicinoids. Multiple linear regression (MLR) coupled with topological substructural molecular descriptor (TOPS-MODE) approach was used. The best MLR model based on only five orthogonalized TOPS-MODE variables allowed us to obtain a coefficient of determination of 0.954 on the training set. The predictive power of the model was validated through a test set and several external validation parameters. This showed that the TOPS-MODE descriptors weighted by bond dipole moments, van der Waals atomic radii, and the total solute hydrogen bond basicity affected pungency. The contributions of certain bonds and fragments to pungency were used to understand the pungency mechanism of capsaicinoids. The selected model can more accurately predict pungency of capsaicinoids compared than those found in the literature, and especially bring insights into the structural features and chemical factors related to pungency.

Retrospective Analysis of 2019-nCov-Infected Cases in Dongyang, Southeastern China

The 2019 novel coronavirus (2019-nCov) has caused increasing number of infected cases globally. This study was performed to analyze information regarding the transmission route and presence of viral nucleic acids on several clinical samples. Confirmed 2019-nCov-infected cases were identified in Dongyang and were treated according to guidelines for the diagnosis of 2019-nCov infection released by the National Health Commission. Information regarding the contacts that the infected people had was collected to determine whether it caused clustered cases. A series of successive nucleic acid examination of feces, oropharyngeal swabs, and sputum was also performed, and the results were analyzed. A total of 19 confirmed cases of 2019-nCov infection were identified in Dongyang, Zhejiang Province, China. Five cases showed severe symptoms, and the remaining ones showed mild manifestations. Ten cases infected from two asymptomatic individuals were clustered into two groups. Among 14 cases with consecutive nucleic acid test results, four patients showed positive results in feces after their negative conversion in oropharyngeal swabs. Asymptomatic individuals with the virus could cause 2019-nCov clustered cases, and the clustered cases may differ from sporadic cases on age and length of hospitalization. In addition, nucleic acids in feces last longer than those in oropharyngeal swabs.

Non-invasive prediction of fetal growth restriction by whole-genome promoter profiling of maternal plasma DNA: a nested case-control study

Objective

To predict fetal growth restriction (FGR) by whole‐genome promoter profiling of maternal plasma.

Design

Nested case–control study.

Setting

Hospital‐based.

Population or Sample

810 pregnancies: 162 FGR cases and 648 controls.

Methods

We identified gene promoters with a nucleosome footprint that differed between FGR cases and controls based on maternal plasma cell‐free DNA (cfDNA) nucleosome profiling. Optimal classifiers were developed using support vector machine (SVM) and logistic regression (LR) models.

Main outcome measures

Genes with differential coverages in promoter regions through the low‐coverage whole‐genome sequencing data analysis among FGR cases and controls. Receiver operating characteristic (ROC) analysis (area under the curve [AUC], accuracy, sensitivity and specificity) was used to evaluate the performance of classifiers.

Results

Through the low‐coverage whole‐genome sequencing data analysis of FGR cases and controls, genes with significantly differential DNA coverage at promoter regions (−1000 to +1000 bp of transcription start sites) were identified. The non‐invasive ‘FGR classifier 1’ (C_FGR1) had the highest classification performance (AUC, 0.803; 95% CI 0.767–0.839; accuracy, 83.2%) was developed based on 14 genes with differential promoter coverage using a support vector machine.

Conclusions

A promising FGR prediction method was successfully developed for assessing the risk of FGR at an early gestational age based on maternal plasma cfDNA nucleosome profiling.

Tweetable abstract

A promising FGR prediction method was successfully developed, based on maternal plasma cfDNA nucleosome profiling.

A promising FGR prediction method was successfully developed, based on maternal plasma cfDNA nucleosome profiling.

Exfoliated near infrared fluorescent silicate nanosheets for (bio)photonics

Imaging of complex (biological) samples in the near-infrared (NIR) is beneficial due to reduced light scattering, absorption, phototoxicity, and autofluorescence. However, there are few NIR fluorescent materials known and suitable for biomedical applications. Here we exfoliate the layered pigment CaCuSi4O10 (Egyptian Blue, EB) via ball milling and facile tip sonication into NIR fluorescent nanosheets (EB-NS). The size of EB-NS can be tailored to diameters <20 nm and heights down to 1 nm. EB-NS fluoresce at 910 nm and the fluorescence intensity correlates with the number of Cu2+ ions. Furthermore, EB-NS display no bleaching and high brightness compared with other NIR fluorophores. The versatility of EB-NS is demonstrated by in-vivo single-particle tracking and microrheology measurements in Drosophila melanogaster embryos. EB-NS can be uptaken by plants and remotely detected in a low-cost stand-off detection setup. In summary, EB-NS have the potential for a wide range of bioimaging applications.

In vivo optochemical control of cell contractility at single-cell resolution

The spatial and temporal dynamics of cell contractility plays a key role in tissue morphogenesis, wound healing, and cancer invasion. Here, we report a simple optochemical method to induce cell contractions in vivo during Drosophila morphogenesis at single-cell resolution. We employed the photolabile Ca²⁺ chelator o-nitrophenyl EGTA to induce bursts of intracellular free Ca²⁺ by laser photolysis in the epithelial tissue. Ca²⁺ bursts appear within seconds and are restricted to individual target cells. Cell contraction reliably followed within a minute, causing an approximately 50% drop in the cross-sectional area. Increased Ca²⁺ levels are reversible, and the target cells further participated in tissue morphogenesis. Depending on Rho kinase (ROCK) activity but not RhoGEF2, cell contractions are paralleled with non-muscle myosin II accumulation in the apico-medial cortex, indicating that Ca²⁺ bursts trigger non-muscle myosin II activation. Our approach can be, in principle, adapted to many experimental systems and species, as no specific genetic elements are required.

AID and TET2 co-operation modulates FANCA expression by active demethylation in diffuse large B cell lymphoma

Diffuse large B cell lymphoma (DLBCL) is traced to a mature B malignance carrying abnormal activation-induced cytidine deaminase (AID) expression. AID activity initially focuses on deamination of cytidine to uracil to generate somatic hypermutation and class-switch recombination of the immunoglobulin (Ig), but recently it has been implicated in DNA demethylation of genes required for B cell development and proliferation in the germinal centre (GC). However, whether AID activity on mutation or demethylation of genes involves oncogenesis of DLBCL has not been well characterized. Our data demonstrate that the proto-oncogene Fanconi anaemia complementation group A (FANCA) is highly expressed in DLBCL patients and cell lines, respectively. AID recruits demethylation enzyme ten eleven translocation family member (TET2) to bind the FANCA promoter. As a result, FANCA is demethylated and its expression increases in DLBCL. On the basis of our findings, we have developed a new therapeutic strategy to significantly inhibit DLBCL cell growth by combination of the proteasome inhibitor bortezomib with AID and TET2 depletion. These findings support a novel mechanism that AID has a crucial role in active demethylation for oncogene activation in DLBCL.

Expression and significance of peripheral myeloid-derived suppressor cells in chronic hepatitis B patients

BACKGROUND

Myeloid-derived suppressor cells (MDSCs) exert their suppressive effects on multiple immune response and contribute to the development of many diseases. However, limited data is available on the involvement of MDSCs in human chronic HBV infection.

OBJECTIVE

To investigate whether the progression of chronic HBV infection was associated with imbalance of MDSCs.

METHODS

The percentages of MDSCs, regulatory T (Treg), Th1 and Tc1 cells in the peripheral blood from chronic hepatitis B (CHB) patients and healthy controls (HC) were determined by flow cytometry. Plasma levels of IL-10, TGF-β and IFN-γ were measured using enzyme-linked immunosorbent assay. The potential association of the frequencies of MDSCs with clinical parameters was assessed.

RESULTS

The percentages of MDSCs and Treg cells were significantly higher in CHB patients than those in HC. The percentages of MDSCs were negatively correlated with Th1 cells. Increased plasma IL-10 level and decreased IFN-γ level were found in CHB patients compared with HC. Moreover, the frequencies of MDSCs and plasma IL-10 levels were positively correlated with serum HBV DNA loads, as well as liver function impairment.

CONCLUSION

The expanded peripheral MDSCs may contribute to poor viral clearance and disease progression during chronic HBV infection.

Expression of IL-17A, E, and F and their receptors in non-small-cell lung cancer

Lung cancer is the leading cause of cancer-related morbidity and mortality worldwide. Interaction of nascent or established lung tumour cells with various cytokines and infiltrating immune cells has been implicated in lung cancer pathogenesis. In this study, we systematically analysed immunoreactivity for IL-17A, IL-17E and IL-17F and their relevant receptors in the lung sections from non-small cell lung cancer (NSCLC) and normal control. Immunoreactivity for IL-17A, IL-17F, IL-17RA and IL- 17RC, but not IL-17RB was significantly elevated in NSCLC compared with controls, while IL-17E was reduced. The median numbers of infiltrating lymphocytes and neutrophils and global macrophage (CD68) immunoreactivity of phagocytes were also elevated in NSCLC compared with control tissue sections. Furthermore, correlation between the expression of IL-17A and its receptors IL-17RA and IL- 17RC varied according to NSCLC histopathological type. These data suggest that IL-17A, E, F and their receptors IL-17RA, RB, RC may be involved in the pathogenesis of NSCLC. Further understanding of the relationship between the IL-17/IL-17R axis and the tumour inflammatory microenvironment may reveal new therapeutic targets.

Global transcriptome analysis to identify critical genes involved in the pathology of osteoarthritis

Objectives

The aim of this study was to identify key pathological genes in osteoarthritis (OA).

Methods

We searched and downloaded mRNA expression data from the Gene Expression Omnibus database to identify differentially expressed genes (DEGs) of joint synovial tissues from OA and normal individuals. Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analyses were used to assess the function of identified DEGs. The protein-protein interaction (PPI) network and transcriptional factors (TFs) regulatory network were used to further explore the function of identified DEGs. The quantitative real-time polymerase chain reaction (qRT-PCR) was applied to validate the result of bioinformatics analysis. Electronic validation was performed to verify the expression of selected DEGs. The diagnosis value of identified DEGs was accessed by receiver operating characteristic (ROC) analysis.

Results

A total of 1085 DEGs were identified. KEGG pathway analysis displayed that Wnt was a significantly enriched signalling pathway. Some hub genes with high interactions such as USP46, CPVL, FKBP5, FOSL2, GADD45B, PTGS1, and ZNF423 were identified in the PPI and TFs network. The results of qRT-PCR showed that GADD45B, ADAMTS1, and TFAM were down-regulated in joint synovial tissues of OA, which was consistent with the bioinformatics analysis. The expression levels of USP46, CPVL, FOSL2, and PTGS1 in electronic validation were compatible with the bio-informatics result. CPVL and TFAM had a potential diagnostic value for OA based on the ROC analysis.

Conclusion

The deregulated genes including USP46, CPVL, FKBP5, FOSL2, GADD45B, PTGS1, ZNF423, ADAMTS1, and TFAM might be involved in the pathology of OA.

Cite this article: X. Zhang, Y. Bu, B. Zhu, Q. Zhao, Z. Lv, B. Li, J. Liu. Global transcriptome analysis to identify critical genes involved in the pathology of osteoarthritis. Bone Joint Res 2018;7:298–307. DOI: 10.1302/2046-3758.74.BJR-2017-0245.R1.

A 'molecular guillotine' reveals the interphase function of Kinesin-5

Motor proteins are important for transport and force generation in a variety of cellular processes and in morphogenesis. Here, we describe a general strategy for conditional motor mutants by inserting a protease cleavage site into the 'neck' between the head domain and the stalk of the motor protein, making the protein susceptible to proteolytic cleavage at the neck by the corresponding protease. To demonstrate the feasibility of this approach, we inserted the cleavage site of the tobacco etch virus (TEV) protease into the neck of the tetrameric motor Kinesin-5. Application of TEV protease led to a specific depletion and functional loss of Kinesin-5 in Drosophila embryos. With our approach, we revealed that Kinesin-5 stabilizes the microtubule network during interphase in syncytial embryos. The 'molecular guillotine' can potentially be applied to many motor proteins because Kinesins and myosins have conserved structures with accessible neck regions.This article has an associated First Person interview with the first author of the paper.

Comparative Study for the Association of Mitochondrial Haplogroup F+ and Metabolic Syndrome between Longevity and Control Population in Guangxi Zhuang Autonomous Region, China

BACKGROUND

Our previous study suggested that mitochondrial haplogroup F (mtDNA F) was a longevity-associated biomarker, but the effect of mitochondrial haplogroup F on longevity individuals with metabolic syndrome (MetS) was not clear. Thus we explored the association between mtDNA F and MetS among longevity and control population in Guangxi Zhuang Autonomous Region, China.

METHOD

A total of 793 individuals consisting of 307 long-lived participants and 486 local healthy controls were involved in this study. Genotypes of mtDNA F were amplified by polymerase chain reaction and Sanger sequenced. MetS was defined according to the revised National Cholesterol Education Program's Adult Treatment Panel III (NCEP ATPIII ) criteria.

RESULTS

The prevalence of MetS in longevity group (28.0%) was higher than that (18.5%) in control group (P=0.002). Through the case-control stratify analysis, the prevalence of MetS in mtDNA F+ longevity individuals (29.8%) was 4.6 fold higher than that (5.3%) in local control group (P<0.001). However, after further longevity-only analysis, no association between MetS and mtDNA F+ in longevity group was observed (P=0.167). Following same analysis of two variables in control group, we found that the prevalence of MetS in mtDNA F- (95.8%) was higher than that in mtDNA F+ (5.3%); conversely, the prevalence of non-metabolic syndrome (NMetS) in mtDNA F+ (94.7%) was markedly higher than that in mtDNA F- (4.2%) (P<0.001).

CONCLUSION

We demonstrated that mtDNA F+ , as a molecuar biomarker, might not only confer beneficial effect to resistance against MetS but also function as a positive factor for long-life span among the population in Guangxi Zhuang Autonomous Region, China.

[Detection of UGT1A1*28 Polymorphism Using Fragment Analysis]

背景与目的

尿苷二磷酸葡萄糖醛酸转移酶（uridine diphosphate glucuronosyl transferase 1A1, UGT1A1）是伊立替康代谢最主要的同工酶，UGT1A1基因的多态性影响UGT1A1的活性，本研究建立片段分析法检测UGT1A1^*28 TATA盒的多态性。

方法

调取2014年4月-2015年5月在广东省人民医院的住院肺癌患者库存血液标本286例，建立片段分析法检测UGT1A1^*28 TATA多态性，与Sanger测序方法比较其精确度和准确度。

结果

286例肿瘤血液中，UGT1A1^*28 TATA盒TA6/6型有236例（82.5%），TA6/7型有48例（16.8%），TA7/7型2例（0.7%）。片段分析法与Sanger测序法比较，精确度与准确度达100%。

结论

片段分析法适用于临床检测UGT1A1^*28多态性，成本低且方便快捷。

The effect of aspirin on circulating tumor cells in metastatic colorectal and breast cancer patients: a phase II trial study

PURPOSE

Aspirin could reduce the risk of cancer metastasis. Circulating tumor cells (CTCs) are a key factor of cancer metastasis, but no evidence has revealed how aspirin affects CTCs and its epithelial-mesenchymal transition (EMT). Here, we conducted a clinical trial to investigate how aspirin affects CTCs in metastatic colorectal cancer (MCC) and breast cancer patients (MBC).

METHODS

The trial is retrospective registered at clinicaltrials.gov (NCT02602938). The eligible patients are given 100 mg aspirin q.d. for 8 weeks, and CTCs are evaluated at baseline, 4 and 8 weeks for absolute number, phenotype (epithelial type, E+, mesenchymal type, M+, and biophenotypic type, B+), and vimentin expression.

RESULTS

Data on 21 MCC and 19 MBC patients are analyzed, and it revealed that the CTC numbers decreased with aspirin treatment in MCC (p < 0.001) but not MBC (p = 0.0532); besides, ratio of E+ CTCs increased (p = 0.037) and M+ CTCs decreased at 2 months in MCC (p = 0.013), but neither the ratio of E+ or M+ CTCs changes significantly in MBC; vimentin expression of M+ CTCs is higher than E+ and B+ CTCs either in MBC or MCC patients at baseline (p < 0.01); and aspirin suppresses the vimentin expression in M+ (p = 0.002)and B+ (p = 0.006) CTCs of MCC and M+ CTCs of MBC (p = 0.004); besides it find vimentin expression in B+ (p = 0.004) or M+ (p < 0.001), CTCs are markedly decreased in patients with total CTC numbers declined.

CONCLUSION

Aspirin could decrease CTCs numbers and block EMT transition in MCC patients and part of MBC patients.

Matrix metalloproteinase family polymorphisms and the risk of aortic aneurysmal diseases: A systematic review and meta-analysis

It has been suggested that matrix metalloproteinase (MMP) polymorphisms are associated with the pathogenesis of aortic aneurysmal diseases. In this study, we conducted a systematic review with an update meta-analysis to investigate the relationship between MMP family polymorphisms and aortic aneurysmal diseases. We systematically reviewed 24 polymorphisms in 8 MMP genes related to the risk of abdominal aortic aneurysm (AAA), thoracic AA or thoracic aortic dissection (TAD). A total of 19 case-control studies with 15 highly studied MMP polymorphisms were included in our meta-analysis. Our results suggested that MMP2rs243865, MMP3rs3025058, MMP13rs2252070 polymorphisms were significantly associated with AAA risk, MMP2rs11643630, MMP8rs11225395 polymorphisms were correlated with TAD risk, and MMP9rs3918242 under the dominant model could increase AAA risk in hospital-based subgroup. No associations with aortic aneurysmal diseases were identified for other polymorphisms assessed in our meta-analysis. In summary, some studied MMP polymorphisms associated with the risk of aortic aneurysmal diseases are potential predictive biomarkers for the clinical application. Moreover, other MMP polymorphisms with limited studies but relevant to aortic aneurysmal formation and progression need further prospective and large investigations to confirm results.