In order to understand the prevalence of Akabane disease(AKAD)in Guizhou Province and the molecular characteristics of the isolates,the whole-genome sequence of a strain of Akabane virus(AKAV)from a bovine AKAD-positive sample was determined and analyzed.The genotype and genetic variation of the strain were also explored.Based on the conserved S sequence,a fluores-cence quantitative PCR(qPCR)detection method was established and applied for the investigation of AKAV infection status in four large-scale beef cattle farms of Guizhou.Results showed that the S,M and L fragments of the bovine strain were highly homologous to the Tianjin strain(TJ2016/China/2016)and the Australian strain(JaLAB39/Australia/1959),where they were in the same evolutionary branch and belonged to genotype Ⅱ.Sensitivity assay found that the lowest detection limit was 2.5 X 101 copies/μL.Specificity assay showed the established method detected only AKAV with no amplification on bovine bluetongue virus(BLUV),Pasteurella multocida(PM),bovine infectious rhinotracheitis virus(IBRV)and bovine Mycoplasma bovis.The variation coefficients of inter-and intra batches in the repeatability test were both lower than 2.26％.These findings illus-trated that the established qPCR method had high sensitivity,good specificity and repeatability.A total of 298 serum samples from 4 large-scale beef cattle farms in Qianxi City and Huangping County of Guizhou Province were collected and tested for AKAV by the method.Out of 298 sam-ples,25 positive samples(25/298)were detected as positive with a positive rate of 8.39％.In sum-mary,this work provided the reference data for a deep understanding of the molecular prevalence of AKAV in Guizhou Province and laid foundation for the prevention and control of AKAD.

Pulmonary blast injury has become the main type of trauma in modern warfare, characterized by externally mild injuries but internally severe injuries, rapid disease progression, and a high rate of early death. The injury is complicated in clinical practice, often with multiple and compound injuries. Currently, there is a lack of effective protective materials, accurate injury detection instrument and portable monitoring and transportation equipment, standardized clinical treatment guidelines in various medical centers, and evidence-based guidelines at home and abroad, resulting in a high mortality in clinlcal practice. Therefore, the Trauma Branch of Chinese Medical Association and the Editorial Committee of Chinese Journal of Trauma organized military and civilian experts in related fields such as thoracic surgery and traumatic surgery to jointly develop the Clinical treatment guideline for pulmonary blast injury ( version 2023) by combining evidence for effectiveness and clinical first-line treatment experience. This guideline provided 16 recommended opinions surrounding definition, characteristics, pre-hospital diagnosis and treatment, and in-hospital treatment of pulmonary blast injury, hoping to provide a basis for the clinical treatment in hospitals at different levels.

Hyper-osmotic stress is one of the key factors that decrease the efficiency of biological succinic acid production. To increase the osmotic stress tolerance of succinate-producing Escherichia coli, we studied the influence of IrrE, an exogenous global regulator, on cell osmotic stress resistance. Fermentation results showed that cell growth and succinic acid production by the recombinant increased under different Na+ concentrations. Meanwhile, the maximum dry cell mass, glucose consumption and succinic acid concentration increased 15.6%, 22% and 23%, respectively, when fermented in a 5-L bioreactor. Expressing IrrE improved cell resistance to hyper-osmotic stress. Further comparison of intracellular osmoprotectants (trehalose and glycerol) concentrations showed that trehalose and glycerol concentrations in the recombinant increased. This suggested that introduction of IrrE could enhance intracellular osmoprotectants accumulation which conferred cell with improved resistance to osmotic stress.

Sugarcane molasses containing large amounts of sucrose is an economical substrate for succinic acid production. However, Escherichia coli AFP111 cannot metabolize sucrose although it is a promising candidate for succinic acid production. To achieve sucrose utilizing ability, we cloned and expressed cscBKA genes encoding sucrose permease, fructokinase and invertase of non-PTS sucrose-utilization system from E. coli W in E. coli AFP111 to generate a recombinant strain AFP111/pMD19T-cscBKA. After 72 h of anaerobic fermentation of the recombinant in serum bottles, 20 g/L sucrose was consumed and 12 g/L succinic acid was produced. During dual-phase fermentation comprised of initial aerobic growth phase followed by anaerobic fermentation phase, the concentration of succinic acid from sucrose and sugarcane molasses was 34 g/L and 30 g/L, respectively, at 30 h of anaerobic phase in a 3 L fermentor. The results show that the introduction of non-PTS sucrose-utilization system has sucrose-metabolizing capability for cell growth and succinic acid production, and can use cheap sugarcane molasses to produce succinic acid.
Bioreactors ; Escherichia coli ; genetics ; metabolism ; Escherichia coli Proteins ; genetics ; Fermentation ; Membrane Transport Proteins ; genetics ; Metabolic Engineering ; Molasses ; Saccharum ; chemistry ; Succinic Acid ; chemistry ; Sucrose ; chemistry

OBJECTIVETo investigate the effects of simulated nitrogen-oxygen saturation exposure at a water depth of 50 m on the expression of inflammatory mediators including interleukin-6 (IL-6), interleukin-10 (IL-10), and tumor necrosis factor-alpha (TNF-α) in the external auditory canal (EAC) of rabbits.

METHODSTwo batches of New Zealand rabbits were exposed to nitrogen-oxygen saturated at a water depth of 50 m. After exposure, the epithelial tissue in the EAC was analyzed using hematoxylin-eosin (HE) staining, and the changes in expression of inflammatory mediators including IL-6, IL-10, and TNF-α in the EAC of rabbits were determined by real-time polymerase chain reaction (PCR).

RESULTSAccording to the result of HE staining, more inflammatory cell infiltration, small vascular congestion, and mucosal edema in the EAC of rabbits were observed in the exposure group than in the control group. Additionally, compared with the control group, the exposure group had increased expression of IL-6 and TNF-α and reduced expression of IL-10 in the EAC of rabbits according to the result of real-time PCR.

CONCLUSIONThe nitrogen-oxygen saturation exposure at a water depth of 50 m can cause inflammatory injuries in the EAC of rabbits. The mechanism may be associated with increased expression of IL-6 and TNF-α and reduced expression of IL-10.

Animals ; Disease Models, Animal ; Ear Canal ; physiopathology ; Environmental Exposure ; adverse effects ; Inflammation Mediators ; metabolism ; Interleukin-10 ; metabolism ; Interleukin-6 ; metabolism ; Nitrogen ; adverse effects ; Oxygen ; adverse effects ; Rabbits ; Tumor Necrosis Factor-alpha ; metabolism ; Water ; adverse effects

BACKGROUNDCigarette smoke induced airway inflammation plays a role in pathogenesis of airway inflammation. Resolvin-D1 derived from omega-3 polyunsaturated fatty acids is an endogenous anti-inflammatory and proresolving lipid mediator. Resolvin-D1 ameliorated inflammatory responses in lung injury, asthma, peritonitis and atherosclerosis. We investigated whether resolvin-D1 suppressed the productions of chemokines and oxidative stress induced by cigarette smoke extract (CSE) in vitro and its possible mechanism.

METHODSWe examined the proinflammatory chemokine interleukin-8 and hydrogen peroxide (H2O2) productions induced by CSE in 16 human bronchial epithelial (16HBE) cells after resolvin-D1 treatment and their mechanisms. 16HBE cells were treated with resolvin-D1 at up to 10 nmol/L, for 30 minutes before CSE up to 16% (v/v) exposure. Release of interlukin-8 proteins was assessed by enzyme linked immunosort assay (ELISA) and its mRNA level by RT-PCR. We evaluated extracellular H2O2 expression in the supernatant. Phosphorylation of NF-κB/p65 and degradation of I-κB in 16HBE cells were determined by Western blotting analysis and NF-κB DNA binding activity by electrophoretic mobility shift assay (EMSA).

RESULTS16HBE cells treated with 8% CSE showed significantly higher interlukin-8 production. Resolvin-D1 pretreatment inhibited CSE induced interlukin-8 production (mRNA and protein) in a dose and time dependent manner. Extracellular H2O2 level decreased after resolvin-D1 treatment. Resolvin-D1 attenuated CSE triggered I-κB degradation and NF-κB/p65 activation dose dependently and inhibited NF-κB DNA binding activity.

CONCLUSIONResolvin-D1 inhibits CSE induced interlukin-8 and H2O2 production in 16HBE cells by modulating NF-κB activation and has therapeutic potential for pulmonary inflammation.

Blotting, Western ; Cell Line ; Cell Survival ; drug effects ; Docosahexaenoic Acids ; pharmacology ; Electrophoretic Mobility Shift Assay ; Enzyme-Linked Immunosorbent Assay ; Humans ; Hydrogen Peroxide ; metabolism ; Interleukin-8 ; metabolism ; NF-kappa B ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Smoking ; adverse effects

Objective To investigate the protective effect of ischemic postconditioning on lung injury in situ during lung ischemic reperfusion.Methods 24 SD rats were randomly divided into 3 groups,sham-operated group(S),ischemic-reperfusion group(I/R) and ischemic postconditioning group (IpostC).IpostC was established by several brief reperfusion-ischemia (30 s,5 cycles) before continuous reperfusion.AKT,p-AKT,p70S6K,p-p70S6K protein expression,apoptotic cells were tested by Western blotting and TUNEL,wet to dry weight ratio(W/D) in lung tissue were determined respectively.The lung pathological changes were also observed.Results Compared with S group,expression of Akt、p-Akt、p70S6K、p-p70S6K and the ratio of W/D,apoptotic index in lung tissue all markedly increased in I/R and IpostC group (P ＜ 0.05).Compared with I/R group,expression of Akt、p-Akt、p70S6K、p-p70S6K markedly increased in IpostC group(P ＜0.05),while the ratio of W/D and apoptotic index significantly reduced (P ＜ 0.05),the pathological injury in IpostC group also reduced significantly.Conclusion IpostC has a protective effect on lung ischemic reperfusion injury via PI3K/Akt pathway.

During the anaerobic fermentation by Escherichia coli AFP111 for succinic acid production, the viable cell concentration and productivity were decreased with the raising of succinic acid concentration. In order to restore cellular succinic acid productivity and prolong fermentation time, we collected strains and refreshed medium for repetitive succinic acid production. However, productivity is lower than that in the anaerobic fermentation before reusing strains. To enhance the productivity, strains were aerobically cultivated for 3 h in pure water before anaerobic fermentation. The activities of key enzymes were enhanced for better performance in producing succinic acid at anaerobic stage. After three rounds of repetitive fermentations, succinic acid concentration and yield reached to 56.50 g/L and 90% respectively. The succinic acid productivity was 0.81 g/(L x h), which was 13% higher than the repetitive fermentations without aerobic activation of the strains.
Aerobiosis ; Anaerobiosis ; Culture Media ; Escherichia coli ; genetics ; metabolism ; Fermentation ; Genetic Engineering ; Glucose ; metabolism ; Industrial Microbiology ; Succinic Acid ; metabolism

Succinic acid is one of the key intermediates in the tricarboxylic acid cycle (TCA)and has huge potentials in biopolymer, food, medicine applications. This article reviews recent research progress in the production of succinic acid by microbial fermentation, including discovery and screening of the succinic-acid-producing microbes, the progress of genetic engineering strategy and metabolic engineering technology for construction of succinic acid-producing strains, and fermentation process control and optimization. Finally, we discussed the limitation of current progress and proposed the future research needs for microbial production of succinic acid.
Actinobacillus ; genetics ; metabolism ; Anaerobiospirillum ; genetics ; metabolism ; Fermentation ; Industrial Microbiology ; methods ; trends ; Metabolic Engineering ; methods ; Succinic Acid ; metabolism

Escherichia coli NZN111 is a promising strain with ldhA and pflB genes inactivated for the production of succinic acid. However, with these mutations, NAD+ could not be regenerated from NADH, and an unbalanced NADH/NAD+ ratio eliminated cell growth and glucose utilization under anaerobic conditions. Nicotinic acid mononucleotide adenylyltransferase (NAMNAT), encoded by the nadD gene, catalyzes the reaction from nicotinic acid mononucleotide (NaMN) to nicotinic acid adenine dinucleotide (NaAD) during the synthetic pathway of NAD(H). Overexpression of the nadD gene could enhance the concentration of NAD(H) and maintain a suitable NADH/NAD+ ratio. In this study, we constructed a recombinant strain E. coli NZN111/pTrc99a-nadD, and overexpressed NAMNAT with 1.0 mmol/L of IPTG under anaerobic conditions in sealed bottles. Compared to E. coli NZN111, the concentrations of NAD+ and NADH in the recombinant strain increased by 3.21-fold and 1.67-fold, respectively. The total concentration of NAD(H) was increased by 2.63-fold, and the ratio of NADH/NAD+ decreased from 0.64 to 0.42. The recombinant strain restored the cell growth and glucose utilization under anaerobic conditions. After 72 h, the recombinant strain could consume 14.0 g/L of glucose to produce 6.23 g/L of succinic acid, and the concentration of succinic acid was 19-fold higher than in E. coli NZN111.
Anaerobiosis ; Escherichia coli ; genetics ; metabolism ; Glucose ; metabolism ; Mutation ; NAD ; metabolism ; Nicotinamide-Nucleotide Adenylyltransferase ; genetics ; metabolism ; Recombinant Proteins ; genetics ; metabolism ; Succinic Acid ; metabolism