Chemico-biological conversion of carbon dioxide

The unabated carbon dioxide(CO_(2))emission into the atmosphere has exacerbated global climate change,resulting in extreme weather events,biodiversity loss,and an intensified greenhouse effect.To address these challenges and work toward carbon(C)neutrality and reduced CO_(2)emissions,the capture and utilization of CO_(2)have become imperative in both scientific research and industry.One cutting-edge approach to achieving efficient catalytic performance involves integrating green bioconversion and chemical conversion.This innovative strategy offers several advantages,including environmental friendliness,high efficiency,and multi-selectivity.This study provides a comprehensive review of existing technical routes for carbon sequestration(CS)and introduces two novel CS pathways:the electrochemicalbiological hybrid and artificial photosynthesis systems.It also thoroughly examines the synthesis of valuable Cnproducts from the two CS systems employing different catalysts and biocatalysts.As both systems heavily rely on electron transfer,direct and mediated electron transfer has been discussed and summarized in detail.Additionally,this study explores the conditions suitable for different catalysts and assesses the strengths and weaknesses of biocatalysts.We also explored the biocompatibility of the electrode materials and developed novel materials.These materials were specifically engineered to combine with enzymes or microbial cells to solve the biocompatibility problem,while improving the electron transfer efficiency of both.Furthermore,this review summarizes the relevant systems developed in recent years for manufacturing different products,along with their respective production efficiencies,providing a solid database for development in this direction.The novel chemical-biological combination proposed herein holds great promise for the future conversion of CO_(2)into advanced organic compounds.Additionally,it offers exciting prospects for utilizing CO_(2)in synthesizing a wide range of industrial products.Ultimately,the present study provides a unique perspective for achieving the vital goals of“peak shaving”and C-neutrality,contributing significantly to our collective efforts to combat climate change and its associated challenges.

Carbothermic reduction of vanadium titanomagnetite with the assistance of sodium carbonate

The carbothermic reduction of vanadium titanomagnetite concentrate(VTC)with the assistance of Na_(2)CO_(3)was conducted in an argon atmosphere between 1073 and 1473 K.X-ray diffraction and scanning electron microscopy were used to investigate the phase transformations during the reaction.By investigating the reaction between VTC and Na_(2)CO_(3),it was concluded that molten Na_(2)CO_(3)broke the structure of titanomagnetite by combining with the acidic oxides(Fe_(2)O_(3),TiO_(2),Al_(2)O_(3),and SiO_(2))to form a Na-rich melt and release FeO and MgO.Therefore,Na_(2)CO_(3)accelerated the reduction rate.In addition,adding Na_(2)CO_(3)also benefited the agglomeration of iron particles and the slag–metal separation by decreasing the viscosity of the slag.Thus,Na_(2)CO_(3)assisted carbothermic reduction is a promising method for treating VTC at low temperatures.

Three Novel Endophytic Fungi as Potential Candidates Producing Bioactive Metabolites Isolated from Metasequoia glyptostroboides

[Objectives]This study was conducted to isolate and investigate the endophytic fungi with antimicrobial activity from the healthy leaves and bark of Metasequoia glyptostroboides Hu&W.C.Cheng regarded as an important medicinal plant in China.[Methods]Endophytic fungi with visible antimicrobial activity were isolated from the healthy leaves and bark of M.glyptostroboides,and primarily screened using Escherichia coli and Staphylococcus aureus as test microorganisms.[Results]Three isolates with relatively higher antimicrobial activity,labeled as MG-01,MG-02,MG-09,were selected for study.Molecular and morphological analysis indicated that the three isolated endophytes belong to Penicillium sp.The ethyl acetate(EtOAc)extracts of the three endophytes were obtained and subjected to the disk diffusion assay,using E.coil,S.aureus,Pseudomonas aeruginosa,Enterococcus faecalis,Monilia albicanas,and Bacillus subtilis as test microorganisms.The minimum inhibitory activity(MIC)of the endophyte with relatively highest antimicrobial activity was determined using two-fold broth micro-dilution method.All the endophytes showed a broad spectrum antimicrobial activity.Among the three endophytes,the strain MG-09 exhibited relatively highest antimicrobial activity with the zones of inhibition(ZOI)ranging from 14.15 to 24.07 mm and MIC ranging from 416.67 to 65.11μg/ml.[Conclusions]The endophytic fungi colonized in M.glyptostroboides are capable of producing effective antimicrobial compounds which may be a potential source for drug discovery and biocide production.

钒钛磁铁矿钠化冶炼渣与SiC耐火材料间的润湿及界面行为研究

为了研究SiC耐火材料在钒钛磁铁矿钠化冶炼工艺中的耐腐蚀性能,本工作对钒钛磁铁矿钠化冶炼渣与SiC耐火材料基板间的润湿及界面行为进行了研究。研究过程采用高温润湿实验装置,以钒钛磁铁矿钠化冶炼渣及SiC耐火材料为实验原料,采用静滴法考察了Na_(2)O含量的变化对熔渣与耐火材料之间润湿及界面行为的影响。结果表明,随着熔渣中Na_(2)O含量的增加,熔渣的熔点明显降低,在SiC基板上润湿铺展效果变好。同一时间及温度下,熔渣与SiC耐火材料基板间的接触角随着Na_(2)O含量的增加而减小,熔渣与SiC耐火材料基板之间的界面能也随之降低,使熔渣与SiC耐火材料基板粘接紧密,两相之间更容易润湿;熔渣中生成的大量含钠低熔点化合物降低了熔渣的黏度,提高了其流动性,渣中分子或离子的传质扩散增强,从而加速了SiC耐火材料的氧化。Na_(2)O含量从20.00wt%增加至40.00wt%,熔渣与基板间从分离状态过度到粘连状态,最终出现均匀的反应层。SiC耐火材料对20.00wt%Na_(2)O含量的熔渣具有较好的抗侵蚀效果,随着Na_(2)O含量增加,抗侵蚀性能逐渐下降。研究结果为钒钛磁铁矿钠化冶炼过程中耐火材料的抗渣研究提供了一定的依据。

Development of a Multiplex Real-Time Quantitative PCR Assay for Detecting Vaginal Microbiota in Chinese Women-China,2021-2022

Introduction:The Nugent score,limited by subjectivity and personnel requirements,lacks accuracy.Establishing a precise and simple molecular test is therefore essential for detecting vaginal microbiota compositions and evaluating vaginal health.Methods:We evaluated the vaginal health of Chinese women using quantitative polymerase chain reaction(qPCR)to target Lactobacillus crispatus(L.crispatus),L.iners,Gardnerella vaginalis(G.vaginalis),Atopobium vaginae(A.vaginae),and Megasphaera phylotype1.bacterial vaginosis(BV)-related bacteria shared a fluorescent channel.Using 16S rDNA sequencing as a reference standard,we evaluated and validated the diagnostic accuracy of the qPCR assay.Results:Both qPCR and 16S rDNA sequencing demonstrated 90.5%concordance in segregating vaginal community state type(CST),as visualized through heatmaps and PCoA.Spearman’s correlation analysis revealed strong correlations between the two methods in calculating the RA of L.crispatus(CST I),L.iners(CST III),and BV-related bacteria(CST IV),with coefficients of 0.865,0.837,and 0.827,respectively.Receiver operating characteristic analysis showed that qPCR had significant diagnostic accuracy for CST I,CST III,and CST IV(molecular BV),with area under the curve values of 0.967,0.815,and 0.950,respectively,indicating strong predictive power.Discussions:Vaginal health can be evaluated using a single qPCR amplification experiment,making the multiplex qPCR assay a highly accurate tool for this purpose.

Na_(2)O-TiO_(2)-SiO_(2)-CaO-Al_(2)O_(3)-V2O5-MnO-MgO-FeO渣系渣铁间硫分配比热力学模型

基于离子分子共存理论(IMCT)建立了Na_(2)O-TiO_(2)-SiO_(2)-CaO-Al_(2)O_(3)-V2O5-MnO-MgO-FeO九元渣系的结构单元作用浓度模型和渣铁间硫分配比热力学模型,并对模型进行实验验证。通过模型计算出1200℃下渣系主要结构单元组成和渣中Na_(2)O,CaO,MnO,MgO和FeO的活度,发现Na_(2)O的加入可促进渣中低熔点物质的生成,降低渣系熔化性温度,改善脱硫反应的动力学条件;同时随着Na_(2)O加入量的增加,渣中Na_(2)O和CaO的活度增加,进而降低渣中S2?离子活度,强化渣铁间脱硫反应。实验结果表明,增加碱矿比提高了渣铁间硫分配比,有利于铁水深度脱硫,铁水中硫含量可降至0.0005wt%以下,硫分配比的理论计算值与实验结果吻合极好。渣中各碱性氧化物的硫分配比随碱矿比RN/C增加逐渐增大,各碱性氧化物硫分配比大小为Na_(2)O>CaO>MnO>FeO>MgO。本研究将共存理论模型成功应用到九元复杂渣系渣铁间脱硫反应机理研究,为铁水深度脱硫过程的渣系优化提供了理论依据。

Longitudinal analysis of immune reconstitution and metabolic changes in women living with HIV:A real-world observational study

Background:Women comprise more than half of people living with human immunodeficiency virus/acquired immune deficiency syndrome(HIV/AIDS)worldwide and incomplete immune recovery and metabolic abnormalities affect them deeply.Studies of HIV antiretroviral therapy(ART)have a low female representation in China.We aimed to investigate immune reconstitution and metabolic changes of female HIV-positive cohort in China longitudinally.Methods:HIV-positive women who initiated ART from January 2005 to June 2021 and were followed up regularly at least once a year were included in this study.Immunological indicators(cluster of differentiation 4[CD4]counts and CD8 counts),viral load(VL),and metabolic indicators were collected at follow-up.All data were collected from the China Disease Prevention and Control Information System(CDPCIS).VL was tested half a year,1 year after receiving ART,and every other year subsequently according to local policy.CD4/CD8 ratio normalization was considered as the primary outcome and defined as a value≥1.Incidence rate and probability of CD4/CD8 ratio normalization were estimated through per 100 person-years follow-up(PYFU)and Kaplan-Meier curve,respectively.Multivariate Cox regression was used to identify independent risk factors associated with CD4/CD8 ratio normalization.We further studied the rate of dyslipidemia,hyperuricemia,diabetes,liver injury,and renal injury after ART initiation with the chi-squared tests or Fisher’s exact probability tests,and a generalized estimating equation model was used to analyze factors of dyslipidemia and hyperuricemia.Results:A total of 494 female patients with HIV/AIDS started ART within 16 years from January 2005 to June 2021,out of which 301 women were enrolled with a median duration of ART for 4.1 years(interquartile range,2.3-7.0 years).The overall incidence rate of CD4/CD8 ratio normalization was 8.9(95%confidence interval[CI],7.4-10.6)per 100 PYFU,and probabilities of CD4/CD8 normalization after initiating ART at 1 year,2 years,5 years,and 10 years follow-up were 11.7%,23.2%,44.0%,and 59.0%,respectively.Independent risk factors associated with CD4/CD8 normalization were baseline CD4 cell counts<200 cells/μL,CD8 counts>1000 cells/μL,and more than 6 months from the start of combined ART(cART)to first virological suppression.Longitudinally,the rate of hypercholesterolemia(total cholesterol[TC])and high triglyceride(TG)showed an increasing trend,while the rate of low high-density lipoprotein cholesterol(HDL)showed a decreasing trend.The rate of hyperuricemia presented a downtrend at follow-up.Although liver and renal injury and diabetes persisted during ART,the rate was not statistically significant.Older age and protease inhibitors were independent risk factors for increase of TC and TG,and ART duration was an independent factor for elevation of TC and recovery of HDL-C.Conclusions:This study showed that women were more likely to normalize CD4/CD8 ratio in comparison with findings reported in the literature even though immune reconstruction was incomplete.

Partial recovery of disturbed V-J pairing profiles of T-cell receptor in people living with HIV receiving long-term antiretroviral therapy

Chronic human immunodeficiency virus(HIV) infection not only causes a gradual loss of CD4~+T cells but also leads to a disturbance of the T cell receptor(TCR) repertoire. In people living with HIV(PLWH), monitoring TCR repertoire is challenged by the inconsistency of complementarity determining region 3(CDR3) and limited cell numbers in clinical samples. Thus, a quantitative method is necessary for monitoring the TCR repertoire in PLWH.We characterized the TCR V-J pairing profile of na?ve and memory CD4~+T cells in healthy donors, HIV-infected antiretroviral therapy(ART)-na?ve patients and long-term(over5 years) ART-experienced patients by performing TCR sequencing. We developed a V-J index with 18 parameters which were subdivided into five categories(expression coverage, cumulative percentage of the top tenth percentile, diversity, intra-individual similarity and inter-individual similarity). In ART-na?ve patients, 14 of the 18 parameters were significantly altered.Long-term ART recovered ten parameters. The four unrecovered parameters were related to inter-individual similarity.Therefore, these findings indicate that long-term ART could only partially recover TCR V-J pairs and introduce newly impacted V-J pairs. Moreover, these results provide new insights into the V-J pairing of the TCR and into the disturbance of TCR repertoire in HIV infection.

Reasons,safety and efficacy analysis for conversion of HAART to TAF/ FTC/BIC among HIV-infected patients

Background:This study aimed to determine the reasons for conversion and elucidate the safety and efficacy of transition to tenofovir alafenamide/emtricitabine/bictegravir sodium(TAF/FTC/BIC)in highly active antiretroviral therapy(HAART)-experienced HIV-infected patients in real-world settings.Methods:We conducted a retrospective cohort study.The treatment conversion rationales,safety,and effectiveness in 1684 HIV-infected patients with previous HAART experience who switched to TAF/FTC/BIC were evaluated at Beijing Ditan Hospital from September 2021 to Auguest 2022.Results:Regimen simplification(990/1684,58.79%)was the most common reason for switching,followed by osteoporosis or osteopenia(375/1684,22.27%),liver dysfunction(231/1684,13.72%),decline in tenofovir alafenamide/emtricitabine/elvitegravir/cobicistat(TAF/FTC/EVG/c)with food restriction(215/1684,12.77%),virological failure(116/1684,6.89%),and renal dysfunction(90/1684,5.34%).In patients receiving non-nucleotide reverse transcriptase inhibitors(NNRTI)-containing regimens,lipid panel changes 1 year after switching indicated a difference of 3.27±1.10 mmol/L vs.3.40±1.59 mmol/L in triglyceride(P=0.014),4.82±0.74 mmol/L vs.4.88±0.72 mmol/L in total cholesterol(P=0.038),3.09±0.70 mmol/L vs.3.18±0.66 mmol/L in low-density lipoprotein(P<0.001),and 0.99±0.11 mmol/L vs.0.95±0.10 mmol/L in high-density lipoprotein(P<0.001).Conversely,among patients receiving booster-containing regimens,including TAF/FTC/EVG/c and lopinavir/ritonavir(LPV/r),lipid panel changes presented decreased trends.We also observed an improved trend in viral load suppression,and alanine transaminase(ALT),aspartate transaminase(AST),estimated glomerular filtration rate(eGFR),and serum creatinine levels after the transition(P<0.001).Conclusion:The transition to TAF/FTC/BIC demonstrated good treatment potency.Furthermore,this study elucidates the motivations behind the adoption of TAF/FTC/BIC in real-world scenarios,providing clinical evidence supporting the stable conversion to TAF/FTC/BIC for HAART-experienced patients.

Association between increased CD177^(+)neutrophils and chronic activation in people living with HIV

To the Editor:Neutrophils,as innate cells,play an important role in the immune defensive response against invading pathogens and provide signals for the proliferation and activation of T and B cells to initiate adaptive immunity.[1]Neutrophils from human immunodeficiency virus(HIV)-1 patients exhibit multiple functional defects,such as impaired antimicrobial killing activity and impaired production of reactive oxygen species(ROS),and an altered phenotype.[2]CD177^(+)neutrophils were identified as a functionally activated cell population.[3]It releases high levels of ROS and antimicrobial peptides compared with CD177^(-)neutrophils under inflammatory conditions.This increased inflammatory cytokine production and ROS generation may have detrimental impacts on the site of stimulation leading to tissue damage,such as epithelial barrier damage resulting in microbial translocation,which is a critical contributor to chronic immune activation during HIV-1 infection.