UV irradiation remodels the specificity landscape of transcription factors.

Somatic mutations are highly enriched at transcription factor (TF) binding sites, with the strongest trend being observed for ultraviolet light (UV)-induced mutations in melanomas. One of the main mechanisms proposed for this hypermutation pattern is the inefficient repair of UV lesions within TF-binding sites, caused by competition between TFs bound to these lesions and the DNA repair proteins that must recognize the lesions to initiate repair. However, TF binding to UV-irradiated DNA is poorly characterized, and it is unclear whether TFs maintain specificity for their DNA sites after UV exposure. We developed UV-Bind, a high-throughput approach to investigate the impact of UV irradiation on protein-DNA binding specificity. We applied UV-Bind to ten TFs from eight structural families, and found that UV lesions significantly altered the DNA-binding preferences of all the TFs tested. The main effect was a decrease in binding specificity, but the precise effects and their magnitude differ across factors. Importantly, we found that despite the overall reduction in DNA-binding specificity in the presence of UV lesions, TFs can still compete with repair proteins for lesion recognition, in a manner consistent with their specificity for UV-irradiated DNA. In addition, for a subset of TFs, we identified a surprising but reproducible effect at certain nonconsensus DNA sequences, where UV irradiation leads to a high increase in the level of TF binding. These changes in DNA-binding specificity after UV irradiation, at both consensus and nonconsensus sites, have important implications for the regulatory and mutagenic roles of TFs in the cell.

Heterologous synthesis of the complex homometallic cores of nitrogenase P- and M-clusters in Escherichia coli.

Nitrogenase is an active target of heterologous expression because of its importance for areas related to agronomy, energy, and environment. One major hurdle for expressing an active Mo-nitrogenase in Escherichia coli is to generate the complex metalloclusters (P- and M-clusters) within this enzyme, which involves some highly unique bioinorganic chemistry/metalloenzyme biochemistry that is not generally dealt with in the heterologous expression of proteins via synthetic biology; in particular, the heterologous synthesis of the homometallic P-cluster ([Fe8S7]) and M-cluster core (or L-cluster; [Fe8S9C]) on their respective protein scaffolds, which represents two crucial checkpoints along the biosynthetic pathway of a complete nitrogenase, has yet to be demonstrated by biochemical and spectroscopic analyses of purified metalloproteins. Here, we report the heterologous formation of a P-cluster-containing NifDK protein upon coexpression of Azotobacter vinelandii nifD, nifK, nifH, nifM, and nifZ genes, and that of an L-cluster-containing NifB protein upon coexpression of Methanosarcina acetivorans nifB, nifS, and nifU genes alongside the A. vinelandii fdxN gene, in E. coli. Our metal content, activity, EPR, and XAS/EXAFS data provide conclusive evidence for the successful synthesis of P- and L-clusters in a nondiazotrophic host, thereby highlighting the effectiveness of our metallocentric, divide-and-conquer approach that individually tackles the key events of nitrogenase biosynthesis prior to piecing them together into a complete pathway for the heterologous expression of nitrogenase. As such, this work paves the way for the transgenic expression of an active nitrogenase while providing an effective tool for further tackling the biosynthetic mechanism of this important metalloenzyme.

Therapeutic efficacy of humanized monoclonal antibodies targeting dengue virus nonstructural protein 1 in the mouse model.

Dengue virus (DENV) which infects about 390 million people per year in tropical and subtropical areas manifests various disease symptoms, ranging from fever to life-threatening hemorrhage and even shock. To date, there is still no effective treatment for DENV disease, but only supportive care. DENV nonstructural protein 1 (NS1) has been shown to play a key role in disease pathogenesis. Recent studies have shown that anti-DENV NS1 antibody can provide disease protection by blocking the DENV-induced disruption of endothelial integrity. We previously demonstrated that anti-NS1 monoclonal antibody (mAb) protected mice from all four serotypes of DENV challenge. Here, we generated humanized anti-NS1 mAbs and transferred them to mice after DENV infection. The results showed that DENV-induced prolonged bleeding time and skin hemorrhage were reduced, even several days after DENV challenge. Mechanistic studies showed the ability of humanized anti-NS1 mAbs to inhibit NS1-induced vascular hyperpermeability and to elicit Fcγ-dependent complement-mediated cytolysis as well as antibody-dependent cellular cytotoxicity of cells infected with four serotypes of DENV. These results highlight humanized anti-NS1 mAb as a potential therapeutic agent in DENV infection.

Dynamics Playing a Key Role in the Covalent Binding of Inhibitors to Focal Adhesion Kinase.

Covalent kinase inhibitors (CKIs) have recently garnered considerable attention, yet the rational design of CKIs continues to pose a great challenge. In the discovery of CKIs targeting focal adhesion kinase (FAK), it has been observed that the chemical structure of the linkers plays a key role in achieving covalent targeting of FAK. However, the mechanism behind the observation remains elusive. In this work, we employ a comprehensive suite of advanced computational methods to investigate the mechanism of CKIs covalently targeting FAK. We reveal that the linker of an inhibitor influences the contacts between the warhead and residue(s) and the residence time in active conformation, thereby dictating the inhibitor's capability to bind covalently to FAK. This study reflects the complexity of CKI design and underscores the importance of considering the dynamic interactions and residence times for the successful development of covalent drugs.

A key component Rxt3 in the Rpd3L histone deacetylase complex regulates development, stress tolerance, amylase production and kojic acid synthesis in Aspergillus oryzae.

Rpd3L is a highly conserved histone deacetylase complex in eukaryotic cells and participates in various cellular processes. However, the roles of the Rpd3L component in filamentous fungi remain to be delineated ultimately. In this study, we constructed two knockout mutants of Rpd3L's Rxt3 subunit and characterized their biological functions in A. oryzae. Phenotypic analysis showed that AoRxt3 played a positive role in hyphal growth and conidia formation. Deletion of Aorxt3 resulted in augmented tolerance to multiple stresses, including cell wall stress, cell membrane stress, endoplasmic reticulum stress, osmotic stress and oxidative stress. Noteworthily, we found that Aorxt3-deleting mutants showed a higher kojic acid production than the control strain. However, the loss of Aorxt3 led to a significant decrease in amylase synthesis. Our findings lay the foundation for further exploring the role of other Rpd3L subunits and provide a new strategy to improve kojic acid production in A. oryzae.

Effect of Pressure and Nonpressure Dressings on Postoperative Complications in Patients With Mixed Hemorrhoids: A Single-blind Controlled Study.

PURPOSE: To compare the clinical effects of nonpressure and pressure dressings on the postoperative complications of modified Milligan-Morgan hemorrhoidectomy. DESIGN: Randomized controlled trial. METHODS: A total of 186 patients with grade II to III mixed hemorrhoids who had been excluded from cardiovascular and cerebrovascular diseases and anorectal surgery were included and randomly assigned to the nonpressure dressings group and the pressure dressings group by random number table. The incidence of acute urinary retention and medical adhesive-related skin injury, pain, hemostatic effect, anal distension, anal edema, use of analgesics, length of hospital stay, and hospitalization costs were compared between the two groups. The Consolidated Standards of Reporting Trials checklist for randomized controlled trials was used in this study. FINDINGS: The incidence of acute urinary retention in both men and women was significantly lower in the nonpressure dressing group (relative risk [RR] = 0.20, 95% confidence interval [CI] [0.13, 0.37], P = .002); (RR = 0.47, 95% CI [0.22, 0.76], P = .015). The postoperative pain at 6 hours/18 hours/25 hours was significantly lower in the nonpressure dressing group (P < .001, P = .004 < 0.05, P = .009). The anal distension at 6 hours and the number of patients who used analgesics were significantly lower in the nonpressure dressing group (P < .001). The incidence of medical adhesive-related skin injuries was significantly lower in the nonpressure dressing group (RR = 0.061, 95% CI [0.020, 0.189], P < .001). No primary bleeding was observed in both groups. However, there were no significant differences between both groups in terms of anal edema scores, length of stay, or hospitalization expenses. No adverse events were reported in either group during the study period. CONCLUSIONS: Nonpressure dressings can effectively reduce the incidence of acute urinary retention and medical adhesion-related skin injury after surgery for grade III to IV mixed hemorrhoids. They can also safely relieve pain and distension.

Non-radical activation of persulfate with Bi2O3/BiO1.3I0.4 for efficient degradation of propranolol under visible light.

Non-radical activation of persulfate (PS) by photocatalysts is an effective approach for removing organic pollutants from aqueous environments. In this study, a novel Bi2O3/BiO1.3I0.4 heterojunction was synthesized using a facile solvothermal approach and used for the first time for non-radical activation of PS to degrade propranolol (PRO) in the presence of visible light. The findings found that the degradation rate of PRO in the Bi2O3/BiO1.3I0.4/PS system was significantly increased from 19% to more than 90% within 90 min compared to the Bi2O3/BiO1.3I0.4 system. This indicated that the composite system exerted an excellent synergistic effect between the photocatalyst and the persulfate-based oxygenation. Quenching tests and electron paramagnetic resonance demonstrated that the non-radical pathway with singlet oxygen as the active species played a major role in the photocatalytic process. The existence of photo-generated holes during the reaction could also be directly involved in the oxidation of pollutants. Meanwhile, a possible PRO degradation pathway was also proposed. Furthermore, the impacts of pH, humic acid and common anions on the PRO degradation by the Bi2O3/BiO1.3I0.4/PS were explored, and the system's stability and reusability were also studied. This study exhibits a highly productive catalyst for PS activation via a non-radical pathway and provides a new idea for the degradation of PRO.

Screening of microRNAs and target genes involved in Sclerotinia sclerotiorum (Lib.) infection in Brassica napus L.

BACKGROUND: Rapeseed (Brassica napus L.) is the third largest source of vegetable oil in the world, and Sclerotinia sclerotiorum (Lib.) is a major soil-borne fungal plant pathogen that infects more than 400 plant species, including B. napus. Sclerotinia stem rot caused an annual loss of 10 - 20% in rapeseed yield. Exploring the molecular mechanisms in response to S. sclerotiorum infection in B. napus is beneficial for breeding and cultivation of resistant varieties. To gain a better understanding of the mechanisms regarding B. napus tolerance to Sclerotinia stem rot, we employed a miRNAome sequencing approach and comprehensively investigated global miRNA expression profile among five relatively resistant lines and five susceptible lines of oilseed at 0, 24, and 48 h post-inoculation. RESULTS: In this study, a total of 40 known and 1105 novel miRNAs were differentially expressed after S. sclerotiorum infection, including miR156, miR6028, miR394, miR390, miR395, miR166, miR171, miR167, miR164, and miR172. Furthermore, 8,523 genes were predicted as targets for these differentially expressed miRNAs. These target genes were mainly associated with disease resistance (R) genes, signal transduction, transcription factors, and hormones. Constitutively expressing miR156b (OX156b) plants strengthened Arabidopsis resistance against S. sclerotiorum accompanied by smaller necrotic lesions, whereas blocking miR156 expression in Arabidopsis (MIM156) led to greater susceptibility to S. sclerotiorum disease, associated with extensive cell death of necrotic lesions. CONCLUSIONS: This study reveals the distinct difference in miRNA profiling between the relatively resistant lines and susceptible lines of B. napus in response to S. sclerotiorum. The identified differentially expressed miRNAs related to sclerotinia stem rot resistance are involved in regulating resistance to S. sclerotiorum in rapeseed by targeting genes related to R genes, signal transduction, transcription factors, and hormones. miR156 positively modulates the resistance to S. sclerotiorum infection by restricting colonization of S. sclerotiorum mycelia. This study provides a broad view of miRNA expression changes after S. sclerotiorum infection in oilseed and is the first to elucidate the function and mechanism underlying the miR156 response to S. sclerotiorum infection in oilseed rape.

Pseudo multishot echo-planar imaging for geometric distortion improvement.

Conventional echo-planar imaging (EPI) uses a radiofrequency pulse for excitation and a prolonged echo train to sample k space, while off-resonance and T2 * decay effects caused by magnetic susceptibility variation accumulate within each echo, leading to geometric distortion. Multishot EPI methods, which divide k space into segments, can shorten the effective echo spacing and reduce the distortion on EPI images. But multiple shots cost longer scan time and render susceptibility to motion. In this study, we propose a new "multishot" EPI method termed pseudo multishot EPI (pmsEPI), in which phase-encoding lines are segmented as in multishot EPI but are collected within a single shot. With the magnetization divided into different pathways via interleaved excitation instead of refocusing in a single long echo train, the total phase error accumulation is reduced in each segmented acquisition, thereby improving distortion of the resultant EPI image. The performance of the pmsEPI method is demonstrated by phantom and in vivo brain experiments on a 3-T scanner. The experimental results show that the distortion displacements of pmsEPI acquisition compared with conventional EPI decrease by 50% with two pseudo shots and 66% with three pseudo shots, validating the ability of the method to obtain images with reduced distortion in a single shot, although magnetization splitting may induce more than 40% SNR loss and minor artifacts. Specifically, the ability of pmsEPI in diffusion-weighted imaging with different trajectory options is highlighted, and the flexibility is demonstrated in a single-shot blip up and down acquisition.

Identification and validation of HOXD3 and UNC5C as molecular signatures in keloid based on weighted gene co-expression network analysis.

BACKGROUND: Keloid is a benign proliferative disease characterized by excessive deposition of extracellular matrix collagen during skin wound healing. The mechanisms of keloid formation have not been fully elucidated, and the current treatment methods are not effective for all keloid patients. Therefore, there is an urgent need to find more effective therapies, and our research focused on identifying characteristic molecular signatures of keloid to explore potential therapeutic targets. METHODS: Gene expression profiles of keloid and control group samples were retrieved from the GEO database. Taking the GSE113619 dataset as the training set, the dataset collected skin tissues from non-lesion sites of healthy and keloid-prone individuals, denoted as Day0. The second sampling was performed 42 days later at the original sampling site of control and keloid groups, denoted as Day42.The 'limma' package and Venn diagram identified differentially expressed genes (DEGs) specific to keloid day42 versus day0 samples. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Reactome pathway functional enrichment, and annotation of the characteristic genes were conducted on the Metascape website. Ingenuity canonical pathways, disease & function enrichment analysis and gene interaction network were performed and predicted in Ingenuity Pathway Analysis (IPA) software. Key module genes related to keloid were filtered out by Weighted Gene Co-expression Network Analysis (WGCNA). We utilized the Least Absolute Shrinkage and Selection Operator (LASSO) algorithm to screen the characteristic genes in keloid by the 'glmnet' package. The area under the curve (AUC) of receiver operating characteristic (ROC) was utilized to determine the effectiveness of potential signatures in discriminating keloid samples from normal samples and performed by using the 'pROC' package. The enrich scores of 24 immune cells in each sample were calculated by the single-sample gene set enrichment analysis (ssGSEA) algorithm， and then the Gene Set Variation Analysis (GSVA) was performed. Finally, RNA from 4 normal and 6 keloid samples was extracted, and RT-qPCR and Western Blot validated the expression of characteristic genes. RESULTS: A total of 640 DEGs specific to keloid day42 versus day0 samples were detected. 69 key module genes were uncovered and implicated in 'NCAM signaling for neurite out-growth', 'oncogenic MAPK signaling', 'transmission across chemical synapses' pathways, and the mitotic cell cycle-related processes. Five characteristic genes (MTUS1, UNC5C, CEP57, NAA35, and HOXD3) of keloid were identified by LASSO, and among which UNC5C and HOXD3 were validated by ROC plot in external dataset, RT-qPCR and Western Blot in validation samples. The result of ssGSEA indicated that the infiltration of neutrophils showed a relatively higher abundance and natural killer cells with relatively low enrichment in the keloid group compared to the control group. UNC5C was correlated with more immune cells compared with other characteristic genes. CONCLUSION: In this study, characteristic genes associated with keloid were identified by bioinformatic approaches and verified in clinical validation samples, providing potential targets for the diagnosis and treatment of keloid.

Ovarian cancer population screening and mortality after long-term follow-up in the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS): a randomised controlled trial.

BACKGROUND: Ovarian cancer continues to have a poor prognosis with the majority of women diagnosed with advanced disease. Therefore, we undertook the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) to determine if population screening can reduce deaths due to the disease. We report on ovarian cancer mortality after long-term follow-up in UKCTOCS. METHODS: In this randomised controlled trial, postmenopausal women aged 50-74 years were recruited from 13 centres in National Health Service trusts in England, Wales, and Northern Ireland. Exclusion criteria were bilateral oophorectomy, previous ovarian or active non-ovarian malignancy, or increased familial ovarian cancer risk. The trial management system confirmed eligibility and randomly allocated participants in blocks of 32 using computer generated random numbers to annual multimodal screening (MMS), annual transvaginal ultrasound screening (USS), or no screening, in a 1:1:2 ratio. Follow-up was through national registries. The primary outcome was death due to ovarian or tubal cancer (WHO 2014 criteria) by June 30, 2020. Analyses were by intention to screen, comparing MMS and USS separately with no screening using the versatile test. Investigators and participants were aware of screening type, whereas the outcomes review committee were masked to randomisation group. This study is registered with ISRCTN, 22488978, and ClinicalTrials.gov, NCT00058032. FINDINGS: Between April 17, 2001, and Sept 29, 2005, of 1 243 282 women invited, 202 638 were recruited and randomly assigned, and 202 562 were included in the analysis: 50 625 (25·0%) in the MMS group, 50 623 (25·0%) in the USS group, and 101 314 (50·0%) in the no screening group. At a median follow-up of 16·3 years (IQR 15·1-17·3), 2055 women were diagnosed with tubal or ovarian cancer: 522 (1·0%) of 50 625 in the MMS group, 517 (1·0%) of 50 623 in the USS group, and 1016 (1·0%) of 101 314 in the no screening group. Compared with no screening, there was a 47·2% (95% CI 19·7 to 81·1) increase in stage I and 24·5% (-41·8 to -2·0) decrease in stage IV disease incidence in the MMS group. Overall the incidence of stage I or II disease was 39·2% (95% CI 16·1 to 66·9) higher in the MMS group than in the no screening group, whereas the incidence of stage III or IV disease was 10·2% (-21·3 to 2·4) lower. 1206 women died of the disease: 296 (0·6%) of 50 625 in the MMS group, 291 (0·6%) of 50 623 in the USS group, and 619 (0·6%) of 101 314 in the no screening group. No significant reduction in ovarian and tubal cancer deaths was observed in the MMS (p=0·58) or USS (p=0·36) groups compared with the no screening group. INTERPRETATION: The reduction in stage III or IV disease incidence in the MMS group was not sufficient to translate into lives saved, illustrating the importance of specifying cancer mortality as the primary outcome in screening trials. Given that screening did not significantly reduce ovarian and tubal cancer deaths, general population screening cannot be recommended. FUNDING: National Institute for Health Research, Cancer Research UK, and The Eve Appeal.

Sharpening up tumor microenvironment to enhance the efficacy of immune checkpoint blockade on head and neck cancer using a CpG-oligodeoxynucleotide.

Head and neck cancers are a type of life-threatening cancers characterized by an immunosuppressive tumor microenvironment. Only less than 20% of the patients respond to immune checkpoint blockade therapy, indicating the need for a strategy to increase the efficacy of immunotherapy for this type of cancers. Previously, we identified a type B CpG-oligodeoxynucleotide (CpG-ODN) called CpG-2722, which has the universal activity of eliciting an immune response in grouper, mouse, and human cells. In this study, we further characterized and compared its cytokine-inducing profiles with different types of CpG-ODNs. The antitumor effect of CpG-2722 was further investigated alone and in combination with an immune checkpoint inhibitor in a newly developed syngeneic orthotopic head and neck cancer animal model. Along with other inflammatory cytokines, CpG-2722 induces the gene expressions of interleukin-12 and different types of interferons, which are critical for the antitumor response. Both CpG-2722 and anti-programmed death (PD)-1 alone suppressed tumor growth. Their tumor suppression efficacies were further enhanced when CpG-2722 and anti-PD-1 were used in combination. Mechanistically, CpG-2722 shaped a tumor microenvironment that is favorable for the action of anti-PD-1, which included promoting the expression of different cytokines such as IL-12, IFN-ß, and IFN-γ, and increasing the presence of plasmacytoid dendritic cells, M1 macrophages, and CD8 positive T cells. Overall, CpG-2722 provided a priming effect for CD8 positive T cells by sharpening the tumor microenvironment, whereas anti-PD-1 released the brake for their tumor-killing effect, resulting in an enhanced efficacy of the combined CpG-2722 and anti-PD-1.

Host Gene Expression to Predict Sepsis Progression.

OBJECTIVES: Sepsis causes significant mortality. However, most patients who die of sepsis do not present with severe infection, hampering efforts to deliver early, aggressive therapy. It is also known that the host gene expression response to infection precedes clinical illness. This study seeks to develop transcriptomic models to predict progression to sepsis or shock within 72 hours of hospitalization and to validate previously identified transcriptomic signatures in the prediction of 28-day mortality. DESIGN: Retrospective differential gene expression analysis and predictive modeling using RNA sequencing data. PATIENTS: Two hundred seventy-seven patients enrolled at four large academic medical centers; all with clinically adjudicated infection were considered for inclusion in this study. MEASUREMENTS AND MAIN RESULTS: Sepsis progression was defined as an increase in Sepsis 3 category within 72 hours. Transcriptomic data were generated using RNAseq of whole blood. Least absolute shrinkage and selection operator modeling was used to identify predictive signatures for various measures of disease progression. Four previously identified gene signatures were tested for their ability to predict 28-day mortality. There were no significant differentially expressed genes in 136 subjects with worsened Sepsis 3 category compared with 141 nonprogressor controls. There were 1,178 differentially expressed genes identified when sepsis progression was defined as ICU admission or 28-day mortality. A model based on these genes predicted progression with an area under the curve of 0.71. Validation of previously identified gene signatures to predict sepsis mortality revealed area under the receiver operating characteristic values of 0.70-0.75 and no significant difference between signatures. CONCLUSIONS: Host gene expression was unable to predict sepsis progression when defined by an increase in Sepsis-3 category, suggesting this definition is not a useful framework for transcriptomic prediction methods. However, there was a differential response when progression was defined as ICU admission or death. Validation of previously described signatures predicted 28-day mortality with insufficient accuracy to offer meaningful clinical utility.

Physiological and Transcriptomic Analyses Reveal the Effects of Elevated Root-Zone CO2 on the Metabolism of Sugars and Starch in the Roots of Oriental Melon Seedlings.

Root-zone CO2 is a major factor that affects crop growth, development, nutrient uptake, and metabolism. Oriental melon is affected by root-zone gases during growth, the microstructure, sugar and starch contents, enzymatic activities related to sugar and starch metabolism, and gene expression in the roots of oriental melon seedlings were investigated under three root-zone CO2 concentrations (CK: 0.2%, T1: 0.4%, T2: 1.1%). Elevated root-zone CO2 altered the cellular microstructure, accelerated the accumulation and release of starch grains, disrupted organelle formation, and accelerated root senescence. The sugar and starch contents and metabolic activity in the roots increased within a short duration following treatment. Compared to the control, 232 and 1492 differentially expressed genes (DEGs) were identified on the 6th day of treatment in T1 and T2 plants, respectively. The DEGs were enriched in three metabolic pathways. The majority of genes related to sucrose and starch hydrolysis were upregulated, while the genes related to sucrose metabolism were downregulated. The study revealed that oriental melon seedlings adapt to elevated root-zone CO2 stress by adjusting sugar and starch metabolism at the transcriptome level and provides new insights into the molecular mechanism underlying the response to elevated root-zone CO2 stress.

Root-Zone CO2 Concentration Affects Partitioning and Assimilation of Carbon in Oriental Melon Seedlings.

Root-zone CO2 is essential for plant growth and metabolism. However, the partitioning and assimilation processes of CO2 absorbed by roots remain unclear in various parts of the oriental melon. We investigated the time at which root-zone CO2 enters the oriental melon root system, and its distribution in different parts of the plant, using 13C stable isotopic tracer experiments, as well as the effects of high root-zone CO2 on leaf carbon assimilation-related enzyme activities and gene expressions under 0.2%, 0.5% and 1% root-zone CO2 concentrations. The results showed that oriental melon roots could absorb CO2 and transport it quickly to the stems and leaves. The distribution of 13C in roots, stems and leaves increased with an increase in the labeled root-zone CO2 concentration, and the δ13C values in roots, stems and leaves increased initially, and then decreased with an increase in feeding time, reaching a peak at 24 h after 13C isotope labeling. The total accumulation of 13C in plants under the 0.5% and 1% 13CO2 concentrations was lower than that in the 0.2% 13CO2 treatment. However, the distributional proportion of 13C in leaves under 0.5% and 1% 13CO2 was significantly higher than that under the 0.2% CO2 concentration. Photosynthetic carbon assimilation-related enzyme activities and gene expressions in the leaves of oriental melon seedlings were inhibited after 9 days of high root-zone CO2 treatment. According to these results, oriental melon plants' carbon distribution was affected by long-term high root-zone CO2, and reduced the carbon assimilation ability of the leaves. These findings provide a basis for the further quantification of the contribution of root-zone CO2 to plant communities in natural field conditions.

Nitrogenase Fe Protein: A Multi-Tasking Player in Substrate Reduction and Metallocluster Assembly.

The Fe protein of nitrogenase plays multiple roles in substrate reduction and metallocluster assembly. Best known for its function to transfer electrons to its catalytic partner during nitrogenase catalysis, the Fe protein is also a key player in the biosynthesis of the complex metalloclusters of nitrogenase. In addition, it can function as a reductase on its own and affect the ambient reduction of CO2 or CO to hydrocarbons. This review will provide an overview of the properties and functions of the Fe protein, highlighting the relevance of this unique FeS enzyme to areas related to the catalysis, biosynthesis, and applications of the fascinating nitrogenase system.

In vivo and in vitro cell-based model of lung adenocarcinoma from patients with pleural effusion.

Lung adenocarcinoma (LAC) is a common and aggressive form of lung cancer that is increasing in incidence among never smokers at a younger age. Current treatment of patients with LAC is insufficient and there is a need for identification of effective biomarkers and development of therapeutic targets. These demands require also improved models for in vivo and in vitro experimentation. In this study, we describe the establishment of two LAC cell lines, named LuCa-3 and LuCa-6. Both were derived from pleural effusion (PE) cells of LAC patients (L3 and L6) and readily propagated as tumor xenografts in immunodeficient mice. PE cells from the patient L6 exhibited also the capacity for in vitro growth and were cultured in two forms: (i) as a suspension growing cell population, labeled LuCa-6S, composed of non-clumping single cells; and (ii) as a monolayer-like culture, labeled LuCa-6A, exhibiting tight cell-to-cell and to culture surface adherence. Unique features of these two sublines and their cell clones are the capacity to convert from a non-clumping single-cell suspension into the adherent growth pattern and vice versa. Immunostaining of patients' tumor tissue xenografts and cultured subline cells displayed markers specific for the phenotype of human LAC. LuCa-6S and LuCa-6A cells did not reveal a noticeable disparity in quantitative growth characteristics. However, a number of differences were detected between these two cell populations manifested in detection or intensities of antigen expressions on the cell surface (CD133, SFTPC) and in the nucleus (TTF-1) including pluripotent (OCT-4, SOX-2, NANOG) genes in cancer stem-like cells (CSCs). Dissimilarities between these two sublines were also detected in N-glycan profiles and in the sensitivity to natural killer cells. Salient features of these subline cell populations are responsiveness to selective upregulation of the pluripotent genes in subsets of CSCs via conversion of their growth patterns and/or by using culture stem media with growth factors. The described in vivo/in vitro model enables broader experimental approaches in studies of lung adenocarcinoma.

Physiological and Proteomic Analyses of Two Acanthus Species to Tidal Flooding Stress.

The mangrove plant Acanthus ilicifolius and its relative, Acanthus mollis, have been previously proved to possess diverse pharmacological effects. Therefore, evaluating the differentially expressed proteins of these species under tidal flooding stress is essential to fully exploit and benefit from their medicinal values. The roots of A. ilicifolius and A. mollis were exposed to 6 h of flooding stress per day for 10 days. The dry weight, hydrogen peroxide (H2O2) content, anatomical characteristics, carbon and energy levels, and two-dimensional electrophoresis coupled with MALDI-TOF/TOF MS technology were used to reveal the divergent flooding resistant strategies. A. ilicifolius performed better under tidal flooding stress, which was reflected in the integrity of the morphological structure, more efficient use of carbon and energy, and a higher percentage of up-regulated proteins associated with carbon and energy metabolism. A. mollis could not survive in flooding conditions for a long time, as revealed by disrupting cell structures of the roots, less efficient use of carbon and energy, and a higher percentage of down-regulated proteins associated with carbon and energy metabolism. Energy provision and flux balance played a role in the flooding tolerance of A. ilicifolius and A. mollis.

Development of a longitudinal two-biomarker algorithm for early detection of ovarian cancer in women with BRCA mutations.

OBJECTIVE: To develop a longitudinal algorithm combining two biomarkers, CA125 and HE4, for early detection of ovarian cancer in women with BRCA mutations. METHODS: Women with BRCA mutations and intact ovaries were invited to participate in a novel ovarian cancer early detection prospective study. The Risk of Ovarian Cancer Algorithm (ROCA) identifying significant increases above each woman's baseline in serum CA125 and HE4 was performed every four months; abnormal risks triggered a subsequent ultrasound. The study first used a risk algorithm for only CA125, a second algorithm was developed for HE4 and finally a risk algorithm combining the two biomarkers was implemented. The ROCA strategy was compared to Standard of Care (SOC) surveillance strategy. RESULTS: A total of 149 women enrolled in the ROCA arm while 43 women enrolled in the SOC arm. Abnormal scores were found in 24% of ROCA CA125 tests, 16% if ROCA CA125 or the novel ROCA HE4 were used independently and reduced to 8% using the new two-marker ROCA, significantly lower than the 15% of abnormal tests seen in the SOC arm (p = 0.042). The average false positive rate among women without ovarian cancer for two-marker ROCA for referral to ultrasound was 6.6% (specificity 93.4%), and for the two-marker ROCA plus ultrasound for referral to surgical consultation was 1.7% (specificity 98.3%). CONCLUSION: A newly developed two-marker ROCA administered every 4 months had lower call-back rates than SOC surveillance. Having established high specificity, the two-marker ROCA score deserves further evaluation for sensitivity in a larger trial.

LncRNA MAGI2-AS3 inhibits the self-renewal of leukaemic stem cells by promoting TET2-dependent DNA demethylation of the LRIG1 promoter in acute myeloid leukaemia.

The presence or absence of cytogenetic mutations is proposed to be responsible for the pathogenesis of acute myeloid leukaemia (AML). However, the current classification system is inadequate to elucidate the molecular heterogeneity of the disease, and therapy failures frequently occur. Leukaemia stem cells (LSCs) initiate and maintain the clonal hierarchy of AML and exhibit properties of self-renewal remaining recalcitrant to conventional chemotherapy. In this study, we identified a novel long non-coding RNA (lncRNA) MAGI2 antisense RNA 3 (MAGI2-AS3) in AML and investigated its functional role in regulating LSCs self-renewal. LSCs were identified by immunoprofiling of CD34+ CD123+ in AML patients' marrow. MAGI2-AS3 exhibited a poor expression level in LSCs than the normal human haematopoietic stem cells. Lentivirus-mediated upregulation of MAGI2-AS3 or leucine-rich repeats and Ig-like domains 1 (LRIG1) impaired LSCs self-renewal. MAGI2-AS3-overexpressed LSCs acquired the ability of self-renewal following lentivirus-mediated knockdown of LRIG1. Methylation-dependent inhibition of LRIG1 was evident in LSCs. MAGI2-AS3 was found to induce occupancy of TET2 at the LRIG1 promoter. Lentivirus-mediated downregulation of TET2 could impair MAGI2-AS3-mediated elevation of LRIG1 and neutralize the inhibitory effect of MAGI2-AS3 on LSCs self-renewal. In vivo analysis indicated an elevated overall survival of NOD/SCID mice injected with LSCs in the presence of MAGI2-AS3. Altogether, the key findings support the potential of lncRNA MAGI2-AS3 to serve as a novel candidate for the improvement of AML treatment.