Exploring Regulation Genes Involved in the Expression of L-Amino Acid Oxidase in Pseudoalteromonas sp. Rf-1

Bacterial L-amino acid oxidase (LAAO) is believed to play important biological and ecological roles in marine niches, thus attracting increasing attention to understand the regulation mechanisms underlying its production. In this study, we investigated genes involved in LAAO production in marine bacterium Pseudoalteromonas sp. Rf-1 using transposon mutagenesis. Of more than 4,000 mutants screened, 15 mutants showed significant changes in LAAO activity. Desired transposon insertion was confirmed in 12 mutants, in which disrupted genes and corresponding functionswere identified. Analysis of LAAO activity and lao gene expression revealed that GntR family transcriptional regulator, methylase, non-ribosomal peptide synthetase, TonB-dependent heme-receptor family, Na⁺/H⁺ antiporter and related arsenite permease, N-acetyltransferase GCN5, Ketol-acid reductoisomerase and SAM-dependent methytransferase, and their coding genes may be involved in either upregulation or downregulation pathway at transcriptional, posttranscriptional, translational and/or posttranslational level. The nhaD and sdmT genes were separately complemented into the corresponding mutants with abolished LAAO-activity. The complementation of either gene can restore LAAO activity and lao gene expression, demonstrating their regulatory role in LAAO biosynthesis. This study provides, for the first time, insights into the molecular mechanisms regulating LAAO production in Pseudoalteromonas sp. Rf-1, which is important to better understand biological and ecological roles of LAAO

Efficacy and mechanism of Baicao Fuyanqing suppository on mixed vaginitis based on 16S rRNA and metabolomics

BackgroundMixed vaginitis is the infection of the vagina by at least two different pathogens at the same time, both of which contribute to an abnormal vaginal environment leading to signs and symptoms. Baicao Fuyanqing suppository (BCFYQ) is a Miao ethnomedicine, used to treat various vaginitis. The aim of this study was to investigate the efficacy and possible mechanism of BCFYQ in the treatment of mixed vaginitis based on 16S rRNA high-throughput sequencing and metabonomics.MethodsEscherichia coli and Candida albicans were used to establish mixed vaginitis model in SD rats. Three groups of low, medium and high doses (0.18/0.36/0.64 g.kg-1) were established, and administered vaginally once a day for 6 consecutive days. After the last administration, vaginal pH and IL-1β, IL-2, IL-13 and IgA levels were measured, and the vaginal tissue was examined pathologically. In addition, the vaginal flora was characterised by 16S rRNA, and endogenous metabolites in the vaginal tissue were detected by UHPLC-Q-Exactive MS.ResultsCompared with the model group, BCFYQ can reduce the vaginal pH of rats, make it close to the normal group and improve the damaged vaginal epithelial tissue. The results of ELISA showed that BCFYQ decreased the levels of IL-1 β and IL-2 and increased the levels of IL-13 and IgA (P<0.05). In addition, BCFYQ may increase the abundance of vaginal flora, especially Lactobacillus. The differential metabolite enrichment pathway suggests that the therapeutic mechanism of BCFYQ is mainly related to lipid metabolism and amino acid metabolism.ConclusionOur research shows that BCFYQ has a good therapeutic effect on mixed vaginitis. It repairs the damaged vaginal mucosa by regulating the vaginal flora and lipid metabolism disorders to improve the local immune function of the vagina and inhibit the growth and reproduction of pathogens

Modified nusinersen intrathecal injection method: inclusion of a septal needle-free closed infusion connector

ObjectiveNusinersen, an extremely expensive biologic drug (around 100,000 US$ per dose) that needs to be administered intrathecally, is approved for the treatment of 5q-spinal muscular atrophy (SMA). Because of the low muscle tone of the back muscles of pediatric SMA patients, especially type 1 SMA patients, the safe, effective, and fast execution of sheath injection is needed. Therefore, a modified intrathecal injection method was developed accordingly. This paper aims to describe the applicability and safety of this modified method.MethodsThe modified intrathecal injection method (MIIM) mainly includes a septal needle-free closed infusion connector between the lumbar puncture needle and the syringe, besides the procedures of routine lumbar puncture. Its applicability and safety were evaluated through clinical observation.ResultsA total of 92 children with SMA have successfully received nusinersen treatment at our hospital using the modified method since 2019 without obvious adverse events related to the modified injection method. Based on the clinical feedback of operators, the advantages of the modified method include successfully injecting the total dose of nusinersen with constant injection rate and a more stable fixation of the puncture needle, as well as making the operator more relaxed. However, compared with the routine method, the procedure of the modified method has additional steps.ConclusionThe modified intrathecal injection method is an effective and safe method to inject nusinersen when weighing the pros and cons, and it may also be used for administering intrathecal injections of other expensive medicines or for patients with other strict requirements for intrathecal injection

A dependability case construction approach based on dependability deviation analysis

As computer-based systems play an important role in our daily life, dependability assessment of these systems is of great significance. Simply combining the result of each dependability attribute could not reflect system dependability faithfully. Therefore, holistic methods to assess dependability are necessary. As a new and promising method which focused on demonstrating the dependability of product-specific system, structured assurance case model receives growing attention. Build a dependability case systematically and effectively is challenging work, particularly for systems which involves multi-contractor who have different responsibilities. In this paper, we proposed a new dependability case construction method to address the ownership problem of system dependability case which involves multiple contractors. Our method extends the existing Dependability Deviation Analysis with contractors analysis and elicitation and integrates the contractors information into the whole dependability argument architecture. We illustrate our contributions by application to a Train Control and Monitor System which preliminarily shows the effectiveness of our method

A New Approach to Assessment of Confidence in Assurance Cases

An assurance case is a body of evidence organized into an argument demonstrating that some claims about a system hold. It is generally developed to support claims in areas such as safety, reliability, maintainability, human factors, security etc. Practically, both argument and evidence are imperfect, resulting in that we can hardly say the claim is one hundred percent true. So when we do decision-making against assurance cases, we need to know how much confidence we hold in the claims. And the quantitative confidence would provide benefits over the qualitative one. In this paper, an approach is proposed to assess the confidence in assurance cases (mainly arguments) quantitatively. First we convert Argument Metamodel based (ARM-based) cases into a set of Toulmin model instances; then we use Hitchcock’s evaluative criteria for solo-verb-reasoning to analyze and quantify the Toulmin model instances into Bayesian Belief Network (BBN); running the Bayesian Belief Network, we get quantified confidence from each claim of the assurance case. Finally, we illustrate our approach by using a simplified fragment from safety cases and discuss several future work

Reconstruction Of A System Of National Parks And Protected Areas In China And Russia According To New Demands And Challenges Facing Implementation Of The Belt And Road Project

The Protected Areas (PA) system serves to support healthy ecosystems and threatened species, biodiversity and ecosystem services, as well as providing multiple benefits to people. The ecological doctrine ofRussiaconsiders the development of a system of specially protected natural areas (SPNA) to be one of the key directions of state policy. In the history of this country, the creation of SPNA is a traditional and effective step, but currently, state environmental policy is very different from that of the policy of the past, as dictated by theUSSR. Today’s global events, such as the economic collapse resulting from the COVID-19 epidemic, have changed social life dramatically. However, for bothRussiaandChina, there is a clear interest in not repeating Western national park commercialization, as seen in theUSand European countries. The authors consider the idea of adding a new wilderness protected area category, because in reality, it is a very effective form of environmental conservation, especially in «Eastern»Russia. It is discussed that the terrestrial protected area system is not ecologically representative at present, although most countries have reported considerable success in this field.Chinahas declared and is promoting the construction of a community with a «shared future for humanity». The focus of this paper is onChina’s Belt and Road Initiative, as it aims for the functional creation of a new model of international economic cooperation that must include a new and close look at nature conservation

Gly-Leu instead of Gly promoted the proliferation and protein synthesis of chicken intestinal epithelial cells

Amino acids have positive regulatory effects on the function of intestinal epithelial cells (IEC), but in the field of animal nutrition, research on the regulatory effects of amino acids on IEC is still in the initial stages. This study aims to explore the effects of Gly, Gly-Gly, and Gly-Leu on IEC proliferation and their possible mechanisms. Chicken small intestinal epithelial cells were separated using the tissue block method, and other miscellaneous cells were removed for digestion and passage culture. The IEC were cultured in the medium containing 20 nmol/l Gly, Gly-Gly and Gly-Leu for 24 h, and the expression of enterokinase and cytokeratin in cells, the growth curve and activity of IEC, cell cycle, differentially expressed genes, mRNA expression, and protein expression levels of p-mTOR and p-S6K1 in IEC were detected. Enterokinase and cytokeratin were expressed specifically in IEC. The results of growth curve and MTT revealed that the cell viability of IEC was significantly increased after treatment with Gly, Gly-Gly and Gly-Leu. The cell cycle results showed that compared with the control group, Gly, Gly-Gly and Gly-Leu intervention could increase the proportion of IEC in G1 phase, and the proportion in S phase of IEC was decreased. Transcriptome sequencing showed that compared with the control group, there were 54, 28 and 30 differential genes in Gly group, Gly-Gly group and Gly-Leu group, respectively. These genes were mainly enriched in nitric oxide synthesis and protein kinase B signalling, PI3K signal and cellular amino acid biosynthesis and transport signal pathways. RT-PCR results showed that the mRNA expression levels of PCYT2, SPP1, EMC6, GRIA2 and PKD2 were consistent with the sequencing results. Western blot results showed that compared with the control group, the protein expression of p-mTOR and p-S6K1 in Gly group, Gly-Gly group and Gly-Leu group was significantly increased. Gly-Leu can promote the protein synthesis in IEC by activating protein synthesis of mTOR signalling pathway in chicken IEC

Using Earth Observation for Monitoring SDG 11.3.1-Ratio of Land Consumption Rate to Population Growth Rate in Mainland China

Urban sustainable development has attracted widespread attention worldwide as it is closely linked with human survival. However, the growth of urban areas is frequently disproportionate in relation to population growth in developing countries; this discrepancy cannot be monitored solely using statistics. In this study, we integrated earth observation (EO) and statistical data monitoring the Sustainable Development Goals (SDG) 11.3.1: “The ratio of land consumption rate to the population growth rate (LCRPGR)”. Using the EO data (including China’s Land-Use/Cover Datasets (CLUDs) and the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime light data) and census, we extracted the percentage of built-up area, disaggregated the population using the geographically weighted regression (GWR) model, and depicted the spatial heterogeneity and dynamic tendency of urban expansion and population growth by a 1 km × 1 km grid at city and national levels in mainland China from 1990 to 2010. Then, the built-up area and population density datasets were compared with other products and statistics using the relative error and standard deviation in our research area. Major findings are as follows: (1) more than 95% of cities experienced growth in urban built-up areas, especially in the megacities with populations of 5–10 million; (2) the number of grids with a declined proportion of the population ranged from 47% in 1990–2000 to 54% in 2000–2010; (3) China’s LCRPGR value increased from 1.69 in 1990–2000 to 1.78 in 2000–2010, and the land consumption rate was 1.8 times higher than the population growth rate from 1990 to 2010; and (4) the number of cities experiencing uncoordinated development (i.e., where urban expansion is not synchronized with population growth) increased from 93 (27%) in 1990–2000 to 186 (54%) in 2000–2010. Using EO has the potential for monitoring the official SDGs on large and fine scales; the processes provide an example of the localization of SDG 11.3.1 in China