Mobilisation of endothelial progenitor cells： one of the possible mechanisms involved in the chronic administration of melatonin preventing erectile dysfunction in diabetic rats

Diabetes-induced oxidative stress plays a critical role in the mobilisation of endothelial progenitor cells （EPCs） from the bone marrow to the circulation. This study was designed to explore the effects of chronic melatonin administration on the promotion of the mobilisation of EPCs and on the preservation of erectile function in type I diabetic rats. Melatonin was administered to streptozotocin-induced type I diabetic rats. EPCs levels were determined using flow cytometry. Oxidative stress in the bone marrow was indicated by the levels of superoxide dismutase and malondialdehyde. Erectile function was evaluated by measuring the intracavernous pressure during an electrostimulation of the cavernous nerve. The density of the endothelium and the proportions of smooth muscle and collagen in the corpus cavernosum were determined by immunohistochemistry. The administration of melatonin increased the superoxide dismutase level and decreased the malondialdehyde level in the bone marrow. This effect was accompanied by an increased level of circulating EPCs in the diabetic rats. The intracavernous pressure to mean arterial pressure ratio of the rats in the treatment group was significantly greater, compared with diabetic control rats. The histological analysis demonstrated an increase in the endothelial density of the corpus cavernosum after the administration of melatonin. However, melatonin treatment did not change the proportions of smooth muscle and collagen in the corpus cavernosum of diabetic rats. Chronic administration of melatonin has a beneficial effect on preventing erectile dysfunction （ED） in type I diabetic rats. Promoting the mobilisation of EPCs is one of the possible mechanisms involved in the improvement of ED.

Pre-rig mobilization hazard evaluation in offshore oil and gas prospect drilling:A case study of TM field,offshore Niger Delta

TM Field,located offshore Niger Delta in the Gulf of Guinea(Nigeria),has been evaluated for potential drilling hazards prior to the drilling of a proposed oil well.This is in a region where potential hazards that could inhibit successful drilling exercise have not been adequately studied.The study adopted the modern technique of offshore geohazard evaluation that relies mainly on suites of geophysical and shallow geological investigations which include ocean bathymetry using multi-beam echo sounder,sidescan sonar,sub-bottom profiler,magnetic,and 2D-high resolution seismic reflection surveys.The results were integrated to draw inferences about the risk potential of the field.From the bathymetric survey,water depths were found to range from 345 m to 650 m LAT,with seabed relief being 305 m.Water depth at the proposed well location was found to be approximately 450 m and the seabed was found to slope in the northwestern direction.Seafloor gradient was computed as 0.05 across the whole area.Two shallow sub-surface stratigraphic units,labelled A and B,were delineated.Unit A was directly beneath the seafloor and seemed to be composed mainly of clayey/silty sand.Its thickness ranged from 6 m to 70 m across the study area.Unit B appeared to be a layer of sand and its total thickness was not fully delineated.Observable kinks and displacements at the flanks of seabed undulations/depressions on subbottom profiler sections suggested that the depressions may be fault-controlled.On the map generated from the marine magnetic data,a magnetic fault was delineated and this appeared to be coincident with the shallower of the two buried faults on the cross-line seismic section cutting through the proposed well-head location.Interpreted seismic reflection data presented this fault as being inactive.Most of the faults mapped,especially the buried ones,appeared to be inactive except a few.Regions with mapped amplitude anomalies are to be avoided during rig-mobilization operations.Though engineering conditions are expected to vary vertically since layers occur as intercalation,significant lateral variation is not expected within uniform layers of bed.Risk of punch-through associated with clayey formation is expected to be low because the geologic layers are not uniformly and entirely clay.The proposed wellhead location was found to be free of potential hazard sources.

傀儡湖鲢、鳙的生长特性及渔业利用

对江苏昆山市傀儡湖冬季围网捕捞到的鲢(Hypophthalmichthys molitrix)、鱅(Aristichthys mobilis)的生长状况进行了测量分析。结果表明:在保水渔业模式下,鲢、鳙的生长速度慢于传统放养模式;鲢的全长、体重生长方程分别为:Lt=73.12×[1-e-0.35(t+0.86)];Wt=7.74×[1-e-0.35(t+0.86)]2.9031,鳙的全长、体重生长方程分别为:Lt=94.35×[1-e-0.25(t+0.73)];Wt=15.26×[1-e-0.25(t+0.73)]2.7372;鲢体重生长速度以1-3龄较高,生长拐点为2.2龄,鳙体重生长速度以1-4龄较高,生长拐点为3.3龄。为了使鲢、鳙放养的除藻效应和经济效益达到最优,傀儡湖渔业利用鲢应以4龄为起捕年龄,鳙应以5龄为起捕年龄。

一株运动发酵单胞菌Zy-1快速生产乙醇

经多次实验优化，得到运动发酵单胞菌Zy发酵葡萄糖生产乙醇较合适的条件．Zy的诱变菌株Zy-1在该条件下发酵葡萄糖生产乙醇比原始菌株更有较大优势．当葡萄糖浓度为200gL^-1时，发酵48h，乙醇浓度96．5gL^-1，残糖2．3gL^-1，发酵效率为94．42％．Zy-1发酵天然原料米粉、木薯、红薯干等，发酵时间44h，乙醇浓度达95gL^-1以上，发酵效率92％以上．发酵液用DNS法测定，还原糖约2gL^-1，残总糖因原料种类不同，其值有所差异（5～20gL^-1）．经薄层层析分析，发酵液无葡萄糖，而是二糖、三糖等低聚糖．

渤海1999年4月运动类铃虫的平面分布

研究了1999年4月末用浅海III型网在渤海30个站位采集的浮游生物样品中的砂壳纤毛虫,发现砂壳纤毛虫种类单一,几乎全部为运动类铃虫(CodonellopsismobilisWang1936),丰度为32～10731个/m3,碳生物量为0～1.52mg/m3。

基于Mbius带的数字图像置乱

利用M bius带提出了一种数字图像置乱方法,在置乱过程中采用了由离散Logistic映射系统生成的密钥混沌序列.该置乱方法在位置空间进行,具有随机性和变化的多样性.讨论了加密算法的安全性和效率等问题,并给出了实验结果.

生物法生产山梨醇的研究进展

山梨醇在食品添加剂、医药及其他化工领域有着广泛的应用,随着需求量的增加,近年来山梨醇的生物法生产逐渐受到了关注。文章以产山梨醇菌株Zymomonas mobilis的主要特性为出发点,系统阐述了利用Z.mobilis生物法生产山梨醇的研究进展,并展望了未来的发展趋势和实现工业化生产需要解决的问题。

RP-HPLC同时检测Zymomonas mobilis代谢组分方法的研究

优化了高效液相色谱(HPLC)同时检测Zymomonas mobilis发酵液中葡萄糖、乙醇和多种代谢产物的条件和方法,分析了影响因素、回收率和重现性.试验结果表明,选择10 mmol/L pH值为2.5 KH2PO4-H3PO4溶液作为流动相、SunFireTM C18,5μm色谱柱(4.6 mm×150 mm)、二极管阵列检测器,可同时检测出葡萄糖酸、丙酮酸、乳酸、乙酸;选用2 mmol/L硫酸溶液作为流动相、IC-PakTM lon-Exclusion 50 A7μm色谱柱(7.8 mm×300 mm)、示差折光检测器,可同时检测葡萄糖、山梨醇、琥珀酸、乙酸、乙醇.Z.mobilis发酵液的回收率和重现性的结果表明,该方法测定葡萄糖、乙醇和其它产物的相对标准偏差范围为0.005%～0.018%,平均回收率为96.86%～101.99%.

Volar locking distal radius plates show better short-term results than other treatment options: A prospective randomised controlled trial

AIM To compare the outcomes of displaced distal radius fractures treated with volar locking plates and with immediate postoperative mobilisation with the outcomes of these fractures treated with modalities that necessitate 6 wk wrist immobilisation.METHODS A prospective, randomised controlled single-centre trial was conducted with 56 patients who had a displaced radius fracture were randomised to treatment either with a volar locking plate(n = 29), or another treatment modality(n = 27; cast immobilisation with or without wires or external fixator). Outcomes were measured at 12 wk. Functional outcome scores measured were the Patient-Rated Wrist Evaluation(PRWE) Score; Disabilities of the Arm, Shoulder and Hand and activities of daily living(ADLs). Clinical outcomes were wrist range of motion and grip strength. Radiographic parameters were volar inclination and ulnar variance.RESULTS Patients in the volar locking plate group had significantly better PRWE scores, ADL scores, grip strength and range of extension at three months compared with the control group. All radiological parameters were significantly better in the volar locking plate group at 3 mo. CONCLUSION The present study suggests that volar locking plates produced significantly better functional and clinical outcomes at 3 mo compared with other treatment modalities. Anatomical reduction was significantly more likely to be preserved in the plating group. Level of evidence: Ⅱ.

Study on Zymomonas Mobilis Growth and Its Relationship with Glutaminase Production by Using Statistical Tools

Glutaminase is used industrially to enhance flavor and aroma and to enrich foodstuffs nutritionally. It also has potential for pharmaceutical application as anti-leukemia agent. The bacteria of Zymomonas mobilis has been studied for ethanol production, however, there is no study regarding glutaminase production. The aim of the present study was to establish the influencing factors for the growth of Z mobilis and its relationship with glutaminase production using statistical tools. Analysis of variance in blocks was carried out in a complete block design and the Tukey test demonstrated the importance of the components of the culture medium, absence of agitation and fermentation time. Minimum culture medium was used in the optimization varying the glucose concentrations （10, 30, and 50 g/L）, glutamine （0, 0.5 and 1g/L） and culture time （18, 24 and 30 hours）. Maximum production was obtained at 8.86 U/L glutaminase. Optimized conditions were used in the growth kinetics, where typical exponential growth was observed. Glutaminase production was shown to be related to biomass production.

Functional Characterization of CRISPR-Cas System in the Ethanologenic Bacterium Zymomonas mobilis ZM4

CRISPR-Cas (clustered regularly interspaced short palindromic repeats—CRISPR associated proteins) is a RNA-guided defense immune system that prevents some genetic elements such as plasmids and virus from getting into the bacterial cells. Zymomonas mobilis is an ethanologenic bacterium, which encodes a subtype I-F CRISPR-Cas system containing three CRISPR loci and a far distant cas gene cluster. Reverse transcription (RT)-PCR analysis revealed that the CRISPR loci were transcribed on both strands. The Cas proteins were suggested to be expressed based on the previous transcriptomic analysis. Challenging with the invader plasmids containing the artificial protospacer with the protospacer adjacent motif (PAM) of NGG or GG exhibited immune interference activity. However, PAM motif of GG seems more effective than NGG in interference activity. Further, the artificial CRISPR arrays with the spacer sequences targeting to the specific genome sites could also lead to strong immune activity, resulting in almost no transformant grown on the agar plates. It was suggested that bacteria like Z. mobilis ZM4 are lack of the rejoining function to heal the double breakage of genomic DNA made by the CRISPR system. Conclusively, the Type I-F CRISPR-Cas system in Z. mobilis ZM4 is active to functionally defense the invading DNA elements.

Biosensor-assisted CRISPRi high-throughput screening to identify genetic targets in Zymomonas mobilis for high d-lactate production

Lactate is an important monomer for the synthesis of poly-lactate(PLA),which is a substitute for the petrochemical plastics.To achieve the goal of high lactate titer,rate,and yield for commercial production,efficient lactate production pathway is needed as well as genetic targets that affect high lactate production and tolerance.In this study,an LldR-based d-lactate biosensor with a broad dynamic range was first applied into Zymomonas mobilis to select mutant strains with strong GFP fluorescence,which could be the mutant strains with increased d-lactate production.Then,LldR-based d-lactate biosensor was combined with a genome-wide CRISPR interference(CRISPRi)library targeting the entire genome to generate thousands of mutants with gRNA targeting different genetic targets across the whole genome.Specifically,two mutant libraries were selected containing 105 and 104 mutants with different interference sites from two rounds of fluorescence-activated cell sorting(FACS),respectively.Two genetic targets of ZMO1323 and ZMO1530 were characterized and confirmed to be associated with the increased d-lactate production,further knockout of ZMO1323 and ZMO1530 resulted in a 15%and 21%increase of d-lactate production,respectively.This work thus not only established a high-throughput approach that combines genome-scale CRISPRi and biosensor-assisted screening to identify genetic targets associated with d-lactate production in Z.mobilis,but also provided a feasible high-throughput screening approach for rapid identification of genetic targets associated with strain performance for other industrial microorganisms.

Metabolic engineering of an industrial bacterium Zymomonas mobilis for anaerobic l-serine production

Due to the complicated metabolic and regulatory networks of l-serine biosynthesis and degradation,microbial cell factories for l-serine production using non-model microorganisms have not been reported.In this study,a combination of synthetic biology and process optimization were applied in an ethanologenic bacterium Zymomonas mobilis for l-serine production.By blocking the degradation pathway while introducing an exporter EceamA from E.coli,l-serine titer in recombinant Z.mobilis was increased from 15.30 mg/L to 62.67 mg/L.It was further increased to 260.33 mg/L after enhancing the l-serine biosynthesis pathway.Then,536.70 mg/L l-serine was achieved by removing feedback inhibition with a SerA mutant,and an elevated titer of 687.67 mg/L was further obtained through increasing serB copies while enhancing the precursors.Finally,855.66 mg/L l-serine can be accumulated with the supplementation of the glutamate precursor.This work thus not only constructed an l-serine producer to help understand the bottlenecks limiting l-serine production in Z.mobilis for further improvement,but also provides guidance on engineering non-model microbes to produce biochemicals with complicated pathways such as amino acids or terpenoids.

Construction and application of high-quality genome-scale metabolic model of Zymomonas mobilis to guide rational design of microbial cell factories

High-quality genome-scale metabolic models(GEMs)could play critical roles on rational design of microbial cell factories in the classical Design-Build-Test-Learn cycle of synthetic biology studies.Despite of the constant establishment and update of GEMs for model microorganisms such as Escherichia coli and Saccharomyces cerevisiae,high-quality GEMs for non-model industrial microorganisms are still scarce.Zymomonas mobilis subsp.mobilis ZM4 is a non-model ethanologenic microorganism with many excellent industrial characteristics that has been developing as microbial cell factories for biochemical production.Although five GEMs of Z.mobilis have been constructed,these models are either generating ATP incorrectly,or lacking information of plasmid genes,or not providing standard format file.In this study,a high-quality GEM iZM516 of Z.mobilis ZM4 was constructed.The information from the improved genome annotation,literature,datasets of Biolog Phenotype Microarray studies,and recently updated Gene-Protein-Reaction information was combined for the curation of iZM516.Finally,516 genes,1389 reactions,1437 metabolites,and 3 cell compartments are included in iZM516,which also had the highest MEMOTE score of 91%among all published GEMs of Z.mobilis.Cell growth was then predicted by iZM516,which had 79.4%agreement with the experimental results of the substrate utilization.In addition,the potential endogenous succinate synthesis pathway of Z.mobilis ZM4 was proposed through simulation and analysis using iZM516.Furthermore,metabolic engineering strategies to produce succinate and 1,4-butanediol(1,4-BDO)were designed and then simulated under anaerobic condition using iZM516.The results indicated that 1.68 mol/mol succinate and 1.07 mol/mol 1,4-BDO can be achieved through combinational metabolic engineering strategies,which was comparable to that of the model species E.coli.Our study thus not only established a high-quality GEM iZM516 to help understand and design microbial cell factories for economic biochemical production using Z.mobilis as the chassis,but also provided guidance on building accurate GEMs for other non-model industrial microorganisms.

Prospects for engineering Ralstonia eutropha and Zymomonas mobilis for the autotrophic production of 2,3-butanediol from CO_(2)and H_(2)

The decarbonization of the chemical industry and a shift toward circular economies because of high global CO_(2) emissions make CO_(2) an attractive feedstock for manufacturing chemicals.Moreover,H_(2) is a low-cost and carbon-free reductant because technologies such as solar-driven electrolysis and supercritical water(scH_(2)O) gasification enable sustainable production of molecular hydrogen(H_(2)).We review the recent advances in engineering Ralsto-nia eutropha,the representative species of“Knallgas”bacteria,for utilizing CO_(2) and H_(2) to autotrophically produce 2,3-butanediol(2,3-BDO).This assessment is focused on state-of-the-art approaches for splitting H_(2) to supply en-ergy in the form of ATP and NADH to power cellular reactions and employing the Calvin-Benson-Bassham cycle for CO_(2) fixation.Major challenges and opportunities for application and future perspectives are discussed in the context of developing other promising CO_(2) and H_(2)-utilizing microorganisms,exemplified by Zymomonas mobilis.

金沙河水库鲢、鳙生长特征及起捕规格的研究

2007年在金沙河水库分别取鲢(Hypophthalmichthys molitrix)157尾、鳙(Aristichthys mobilis)53尾样本,对其年龄组成和生长特征进行了研究。结果表明,该水库鲢、鳙均以3～4龄为主。体长和体重的关系式分别为WH=1.0×10-4 L2.5135,WA=2.7×10-5 L2.8705。鲢、鳙的生长规律符合von Bertalanffy生长方程,鲢的生长方程分别为LH=112.1244[1-e-0.1544(t+0.1371)],WH=14189.16[1-e-0.1544(t+0.1371)]2.5135;鳙的生长方程分别为LA=68.5382[1-e-0.396(t-0.3239)],WA=5101.875[1-e-0.396(t-0.3239)]2.8705。根据此方程计算出生长速度和生长加速度方程,并得出鲢、鳙生长拐点分别为5.83龄和3.00龄。与不同水库鲢、鳙生长比较,金沙河水库鲢比鳙生长快。并对金沙河水库鲢、鳙的放养和捕捞规格提出了建议。

CRISPR-mediated host genomic DNA damage is efficiently repaired through microhomology-mediated end joining in Zymomonas mobilis

CRISPR-Cas systems provide bacteria and archaea with adaptive immunity against mobile genetic elements(MGEs)through uptake of invader-derived spacers.De novo adaptation samples spacers from both invaders and hosts,whereas primed adaptation shows higher specificity to sample spacers from invaders in many model systems as well as in the subtype I-F system of Zymomonas mobilis.Self-derived spacers will lead to CRISPR self-interference.However,our in vivo study demonstrated that this species used the microhomology-mediated end joining(MMEJ)pathway to efficiently repair subtype I-F CRISPR-Cas system-mediated DNA breaks guided by the self-targeting spacers.MMEJ repair of DNA breaks requires direct microhomologous sequences flanking the protospacers and leads to DNA deletions covering the protospacers.Importantly,CRISPR-mediated genomic DNA breaks failed to be repaired via MMEJ pathway in presence of higher copies of short homologous DNA.Moreover,CRISPR-cleaved exogenous plasmid DNA was failed to be repaired through MMEJ pathway,probably due to the inhibition of MMEJ by the presence of higher copies of the plasmid DNA in Z.mobilis.Our results infer that MMEJ pathway discriminates DNA damages between in the host chromosome versus mobile genetic element(MGE)DNA,and maintains genome stability post CRISPR immunity in Z.mobilis.

People’s Justice: Socialist Law and Equity in China, 1921-1945

When people’s justice was conceived in Republican China, it brought with it a socialist conceptualisation of law and equity, by which the prefix of ‘people’ was not merely a superfluous addition to the term of ‘justice’. On the contrary, it emphasised a people-oriented approach in as much practising the law as correcting the law where arose a rigidity during its application. Such elements as class inequality and the supremacy of state interests were found therein, alongside with Mao*s emphasis on the mass line policy. By dividing the period from 1921 to 1945 into three sections, namely 1921-1927, 1927-1934 and 1935-1945, this article aims to give a brief discussion of the evolution of people's justice, both as a concept and as a system of laws, in China, which may help us to better appreciate the socialist notions and traditions of law and equity.