Glucose oxidase (GOD) is an oxygen-consuming dehydrogenase that can catalyze the production of gluconic acid hydrogen peroxide from glucose, and its specific mechanism of action makes it promising for applications, while the low catalytic activity and poor thermostability have become the main factors limiting the industrial application of this enzyme. In this study, we used the glucose oxidase AtGOD reported with the best thermostability as the source sequence for phylogenetic analysis to obtain the GOD with excellent performance. Six genes were screened and successfully synthesized for functional validation. Among them, the glucose oxidase AhGODB derived from Aspergillus heteromorphus was expressed in Pichia pastoris and showed better thermostability and catalytic activity, with an optimal temperature of 40 ℃, a specific activity of 112.2 U/mg, and a relative activity of 47% after 5 min of treatment at 70 ℃. To improve its activity and thermal stability, we constructed several mutants by directed evolution combined with rational design. Compared with the original enzyme, the mutant T72R/A153P showcased the optimum temperature increasing from 40 to 50 ℃, the specific activity increasing from 112.2 U/mg to 166.1 U/mg, and the relative activity after treatment at 70 ℃ for 30 min increasing from 0% to 33%. In conclusion, the glucose oxidase mutants obtained in this study have improved catalytic activity and thermostability, and have potential for application.
Glucose Oxidase/chemistry* ; Enzyme Stability ; Aspergillus/genetics* ; Pichia/metabolism* ; Temperature ; Catalysis ; Fungal Proteins/metabolism* ; Hot Temperature

AIM:To study the protective effect of transient receptor potential vanilic acid subtype 1(TRPV1)agonist capsaicin(CAP)on traumatic blood loss shock rats,and to further explore its possible mechanism by network pharmacology.METHODS:Forty-five SD rats were divided into 5 groups by random number table method:normal group,shock group,lactated Ringer's solution(LR)group,CAP pretreatment(single administration before shock)group,CAP pre-final administration(twice administration before and after shock)group,with 9 rats in each group for survival observation.Then 32 SD rats were divided into 4 groups according to the results of survival experiment:normal group,shock group,LR group,CAP pre-final administration group,with 8 rats in each group for blood pressure,hemodynamics,arterial blood gas,vascular reactivi-ty and hepaticand renal blood flow.At the same time,the potential mechanism of CAP in the treat-ment of traumatic hemorrhagic shock was investi-gated by network pharmacology.Furthermore,ap-ply the dataset to validate and analyse the diagnos-tic value of the hub genes.RESULTS:Rats in shock group died within hours of the completion of the shock model,and the mean survival time was 1.25(0.42,6.21)h.LR resuscitation could improve the survival of rats to some extent.The survival rate and survival time of rats in the CAP pretreatment group were slightly increased as compared with the LR group,while twice administration of CAP be-fore and after shock(CAP pre-final administration)resulted in better outcomes than LR resuscitation alone.Further results indicated that CAP pre-final administration significantly reduced the blood lac-tic acid level,improved the vasoconstrictive and di-astolic reactivity,and increased the liver and kidney blood flow of shock rats as compared with LR group.The improvement of hemodynamics and blood gas indexes in CAP group was slightly higher than LR group,but there was no statistical signifi-cance.A total of 37 genes related to CAP anti-trau-matic hemorrhage shock were obtained by net-work pharmacology.KEGG enrichment analysis showed that the Ca ion signaling pathway and Ras signaling pathway were significantly enriched.Vali-dation of the dataset showed that the expression levels of CXCR4,NF-kB1,GFPA and NTF3 hub gene were significantly different in the normal and shock groups,and that CXCR4 has a high diagnostic value for traumatic haemorrhagic shock.CONCLUSIONS:CAP,the TRPV1 agonist,significantly improved vas-cular function,increased organ blood flow,and cor-rected the lactic acidosis in rats with traumatic hemorrhagic shock,thus markedly improved the survival outcomes.The mechanism may be related to Ca ion signal pathway and Ras signal pathway.CXCR4,NF-kB1,GFPA and NTF3 may be having an important role in it.

AIM:To study the protective effect of transient receptor potential vanilic acid subtype 1(TRPV1)agonist capsaicin(CAP)on traumatic blood loss shock rats,and to further explore its possible mechanism by network pharmacology.METHODS:Forty-five SD rats were divided into 5 groups by random number table method:normal group,shock group,lactated Ringer's solution(LR)group,CAP pretreatment(single administration before shock)group,CAP pre-final administration(twice administration before and after shock)group,with 9 rats in each group for survival observation.Then 32 SD rats were divided into 4 groups according to the results of survival experiment:normal group,shock group,LR group,CAP pre-final administration group,with 8 rats in each group for blood pressure,hemodynamics,arterial blood gas,vascular reactivi-ty and hepaticand renal blood flow.At the same time,the potential mechanism of CAP in the treat-ment of traumatic hemorrhagic shock was investi-gated by network pharmacology.Furthermore,ap-ply the dataset to validate and analyse the diagnos-tic value of the hub genes.RESULTS:Rats in shock group died within hours of the completion of the shock model,and the mean survival time was 1.25(0.42,6.21)h.LR resuscitation could improve the survival of rats to some extent.The survival rate and survival time of rats in the CAP pretreatment group were slightly increased as compared with the LR group,while twice administration of CAP be-fore and after shock(CAP pre-final administration)resulted in better outcomes than LR resuscitation alone.Further results indicated that CAP pre-final administration significantly reduced the blood lac-tic acid level,improved the vasoconstrictive and di-astolic reactivity,and increased the liver and kidney blood flow of shock rats as compared with LR group.The improvement of hemodynamics and blood gas indexes in CAP group was slightly higher than LR group,but there was no statistical signifi-cance.A total of 37 genes related to CAP anti-trau-matic hemorrhage shock were obtained by net-work pharmacology.KEGG enrichment analysis showed that the Ca ion signaling pathway and Ras signaling pathway were significantly enriched.Vali-dation of the dataset showed that the expression levels of CXCR4,NF-kB1,GFPA and NTF3 hub gene were significantly different in the normal and shock groups,and that CXCR4 has a high diagnostic value for traumatic haemorrhagic shock.CONCLUSIONS:CAP,the TRPV1 agonist,significantly improved vas-cular function,increased organ blood flow,and cor-rected the lactic acidosis in rats with traumatic hemorrhagic shock,thus markedly improved the survival outcomes.The mechanism may be related to Ca ion signal pathway and Ras signal pathway.CXCR4,NF-kB1,GFPA and NTF3 may be having an important role in it.

Non-lethal electric shock devices such as Taser have been widely used by military and police agencies worldwide. Taser can temporarily incapacitate human body mainly through discharge on skeletal muscle, while causing injuries to the tissues and organs such as the heart, skeletal muscle, blood vessel, eyeball, brain, bone and neuropsychiatric behavioral disorders through direct or indirect effects of electrical discharge, mechanical puncture, burning and infection. Though Taser has been introduced into China, there have been few studies about the damage to human body caused by Taser and no relevant systematic medical reviews have been found. However, an overall understanding of the characteristics of Taser injuries to human body is of great significance in reducing the disability and mortality rates caused by Taser as well as treating the injuries. To this end, the authors reviewed the research progress on human body injuries caused by Taser from the characteristics of Taser and the types and features of Taser injuries, aiming to provide references for the diagnosis and treatment of injuries caused by Taser.

AIM: To investigate the relationship between vascular smooth muscle cell (VSMC) injury, organelle stress response and autophagic cell death (autophagy) and ferroptosis induced by the chemical hypoxia inducer cobalt chloride (CoCl2) through the bioinformatics analysis and in vitro cell experimentation. METHODS: The dataset GSE119226 of VSMC treated with cobalt chloride was acquired from the gene expression database (GEO). The R language was used to investigate the relationship between CoCl2 treatment and organelle stress response (Golgi stress, endoplasmic reticulum stress) and two forms of cell death (ferroptosis and autophagic cell death). With primary cultured rat VSMC (rVSMC) and CoCl2-induced anoxia model, the changes in cell viability were detected by CCK-8 method, and reactive oxygen species (ROS) levels were measured using DCFH-DA method. The expression levels of HIF-1α (a key molecule in hypoxia), Golgi stress markers GM130 and p115, endoplasmic reticulum stress markers GRP78 and CHOP, autophagy markers LC3-II / LC3-I and Beclin1, and ferroptosis markers GPx4 and xCT were detected by Western blot. The effect of inducing or inhibiting organelle stress and cell death on the CoCl2-induced cell damage was also observed. RESULTS: Differentially expressed genes analysis of GSE119226 dataset showed that CoCl2 treatment of VSMCs had significant effects on organelle function and stress response, autophagy and ferroptosis-related genes, in which endoplasmic reticulum stress, protein processing in endoplasmic reticulum, regulation of Golgi to plasma membrane protein transport, autophagy / autophagic cell death, and ferroptosis pathways were remarkably enriched. The results of in vitro experiment showed that compared with normal rVSMC, cell viability was significantly decreased after CoCl2 treatment, as well as HIF-1α protein expression and ROS levels in rVSMCs were increased. In rVSMC treated with Co-Cl2, the expression levels of Golgi structural proteins GM130 and p115 (reflecting the occurrence of Golgi stress) were decreased, while the markers GRP78 and CHOP (reflecting the occurrence of endoplasmic reticulum stress) were increased. At the same time, CoCl2 treatment also reduced the expression of autophagy markers LC3-II/LC3-I and Beclin1 (indicating the decrease levels of autophagy), while the expression of ferroptosis markers GPx4 and xCT were decreased (indicating the occurrence of ferroptosis). Compared with CoCl2 treatment group, induced Golgi stress, endoplasmic reticulum stress, or ferroptosis could further reduce cell viability, while inhibition of these processes could improve cell viability. On the other hand, increasing the level of autophagy can improve the cell viability. CONCLUSION: Hypoxia induced by cobalt chloride can lead to VSMC injury. Golgi stress, endoplasmic reticulum stress, ferroptosis, and the reduction of autophagy level play an important role in it. Inhibition of organelle stress response and ferroptosis, or increase of autophagy level can improve VSMC injury caused by cobalt chloride.

Objective:To discuss the effect of fluid resuscitation on the occurrence of ferroptosis in vascular tissue and the structure of vascular cells in the rats with blast injury complicated with hemorrhagic shock,and to clarify its mechanism.Methods:A total of 54 healthy adult SD rats were randomly divided into normal group,blast injury complicated with hemorrhagic shock(model)group,and the fluid resuscitation(treatment)group,and there were 18 rats in each group.Among them,10 rats were randomly selected to observe the surival status and another 8 rats were selected to detect the other indexes.The average survival time(ST),24 h and 72 h survival rates of the rats in various groups were observed;the blood pressure(BP),heart rate(HR),and respiratory rate(RR)of the rats in various groups were observed;the levels of serum creatinine(Scr),blood urea nitrogen(BUN),lactate(LAC),glucose(GLU),iron ions,glutathione(GSH),and malondialdehyde(MDA)and the activities of aspartate aminotransferase(AST),alanine aminotransferase(ALT)and lactate dehydrogenase(LDH)in serum of the rats in various groups were detected;Western blotting method was used to detect the expression levels of ferroptosis marker proteins glutathione peroxidase 4(GPX4),solute carrier family 7 member 11(SLC7A11),and heme oxygenase 1(HO-1)proteins in superior mesenteric artery tissue of the rats in various groups;the pathomorphology of the superior mesenteric artery of the rats in various groups was observed.Results:All the rats in normal group survived for 72 h,while the longest ST of the rats in model group did not exceed 9 h.Compared with model group,the ST and 24 h survival rate(SR)of the rats in treatment group were significantly increased(P＜0.05).Compared with normal group,the BP,HR,and RR of the rats in model group were significantly decreased(P＜0.01).Compared with model group,the BP,HR,and RR of the rats in treatment group were significantly increased after fluid resuscitation(P＜0.05).Compared with normal group,the activities of AST and ALT,and the levels of Scr and BUN in serum of the rats in model group were significantly increased(P＜0.01).Compared with model group,the serum levels of LAC and GLU of the rats in treatment group were significantly decreased(P＜0.01).Compared with normal group,the concentration of iron ion,GSH level,MDA level,LDH activity in serum of the rats in model group were significantly increased(P＜0.05);compared with model group,the concentration of iron ion and LDH activity in serum of the rats in treatment group was significantly decreased(P＜0.01).Compared with normal group,the expression levels of GPX4 and SLC7A11 in superior mesenteric artery tissue of the rats in model group were significantly decreased(P＜0.05);compared with model group,the expression levels of GPX4 and SLC7A11 in superior mesenteric artery tissue of the rats in treatment group were significantly increased(P＜0.05).Compared with normal group,the expression level of HO-1 protein in superior mesenteric artery tissue of the rats in model group was increased(P＜0.01);compared with model group,the expression level of HO-1 protein in superior mesenteric artery tissue of the rats in treatment group was increased(P＜0.01).The microscopic pathology results showed that the cell arrangement in the layers of the superior mesenteric artery tissue of the rats in model group was disordered,the swelling was significant and the thickness was increased;the pathological changes in superior mesenteric artery tissue of the rats in treatment group was alleviated.The ultramicroscopic pathology results showed that the endothelial cell structure of blood vessels of the rats in normal group was intact,and there was no swelling in the subendothelial matrix;the vascular endothelial cell membrane of the rats in model group was damaged,there were cytoplasmic dissolution and fragmentation,and the swelling of the subendothelial matrix was significant;the swelling of the vascular endothelial cells in treatment group was alleviated.Conclusion:Ferroptosis occurs in vascular tissue of the rats with blast injury complicated with hemorrhagic shock,and fluid resuscitation can alleviate the structural damage of the vascular cells by inhibiting the vascular tissue ferroptosis.

Objective To establish a model of combined injury of thermal radiation and blast wave of gas explosion in closed pipeline,and investigate the characteristics of important organ injury induced by burn-blast combined injury in rats.Methods A total of 72 male SD rats(aged 8～10 weeks,weighing 200～10 g)were randomly divided into control group and mild and severe injured groups.After the model rats were inflicted with blast wave and thermal radiation,their physical parameters were detected and measured.The respiratory function of the survival rats was tested.In 24 h later,arterial blood gas analysis,blood biochemical tests,and detection for serum inflammatory factors and lung injury related protein levels were performed,and the pathological changes in the lung tissue and trachea were observed.Results The peak range of explosive blast wave overpressure was 209～493 kPa,and the temperature was 152～258 ℃.The mortality rate was 8.3％in the mild group and 53.1％in the severe group.Compared with the control group,longer inspiratory time(Ti)and relaxation time(Tr)and larger tidal volume(TV)(P＜0.05),while lower respiratory frequency(f)were observed in the 2 injured groups within 6 h after injury(P＜0.05).At 24 h after injury,the values of partial pressure of carbon dioxide(PaCO2),residual base value(BE)and bicarbonate(HCO3-)were increased significantly(P＜0.05),while partial pressure of oxygen(PaO2)was decreased(P＜0.05).The serum levels of alanine transaminase(ALT),aspartate aminotransferase(AST),alkaline phosphatase(ALP),total bilirubin(TBI)and total bile acid(TBA)were notably elevated(P＜0.05).So were the levels of IL-1 β,TNF-α and IL-6(P＜0.01).Various severities of hyperemia foci and inflammation in the tracheal mucosa were observed in the injured rats.The incidence of lung injury was high,and the pathological manifestations were dot-shaped hemorrhage to diffuse hemorrhage of the whole lobe,rupture of alveolar septum,thickening of septum,and infiltration of red blood cells and inflammatory cells.The levels of serum lung injury-related proteins were significantly increased(P＜0.05).Conclusion A rat model which can highly simulate mild to severe burn-blast combined injury is constructed,which can meet the needs for rat model in study of explosive burn-blast compound injury.The main characteristics of the injury are lung injury,respiratory dysfunction,liver damage and secondary infection.

Objective:To investigate the effects of high-energy shock and vibration on cortex injury and peripheral blood immune cells in goats.Methods:Seventeen Boer goats without gender preference were selected. By using random number tables, the goats were divided into normal control group ( n=5) and shock and vibration injury group ( n=12). The goats in the normal control group were anatomized routinely and their brain was collected after being sacrificed without any other treatment. The goats in the high-energy shock and vibration model group were placed on a loading table (part of the BY10-100 instant shock and vibration simulation platform) in a restrained state, and made into a high-energy shock and vibration injury model induced by a vertical impact waveform generator. The intravenous blood samples were taken from the goats in the shock and vibration injury group before and at 0, 3, 6 and 24 hours after injury.Then, the goats were sacrificed and the following procedures were the same as the normal control group. At 24 hours after injury, the brain injury and the histopathological changes of the cerebral cortex in the normal control group and shock and vibration injury group were observed by gross pathological and anatomical examination and HE staining. The mRNA expression of zonula occludens 1 (ZO-1), tight junction protein 5 (Claudin-5), glial fibrillary acidic protein (GFAP), ionized calcium binding adaptor molecule 1 (IBA-1), interleukin (IL)-1β, IL-6 and cluster of differentiation antigen 177 (CD177) of the cerebral cortex in the normal control group and shock and vibration injury group were measured through fluorogenic quantitative polymerase chain reaction. The expression of ZO-1 and Claudin-5 proteins of the cerebral cortex in the normal control group and shock and vibration injury group were detected by Western blotting. Hematology analyzer and coagulation analyzer were used to detect white blood cell count, neutrocyte, lymphocyte, monocyte, prothrombin time 1 (PT-1), prothrombin time international normalized ratio (PT-INR), activated partial thromboplastin time (APTT), thrombin time (TT), prothrombin activity (PTA) and fibrinogen (FIB) levels in goats of the shock and vibration injury group before and at 0, 3, 6 and 24 hours after injury, respectively. Results:At 24 hours after injury, no visible contusion or necrosis was found in goat brain tissue in the shock and vibration injury group; the cerebral micro-vessels presented with a local dilation, hyperemia, edema, aggregation of inflammatory cells, disruption of vessel walls and leakage of red blood cells. These changes were not observed in the normal control group. In the shock and vibration injury group, ZO-1 and Claudin-5 mRNA expressions in the cerebral cortex were 0.25±0.10 and 0.09(0.04, 0.44) respectively, which were significantly lower than those of the normal control group [1.00±0.15 and 0.99(0.80, 1.20)]; GFAP, IBA-1, IL-1β, IL-6 and CD177 mRNA expression levels were 4.40(3.88, 6.75), 2.60±1.07, 3.04±0.51, 2.71±0.45 and 2.93±0.62 respectively, which were significantly higher than those of the normal control group [1.00(0.78, 1.22), 1.00±0.37, 1.00±0.27, 1.00±0.57 and 1.00±0.35]; ZO-1 and Claudin-5 protein expression levels were 0.41±0.06 and 0.42±0.11 respectively, which were significantly lower than those of the normal control group (1.08±0.12 and 0.91±0.23) (all P<0.01). In the shock and vibration injury group, the levels of white blood count, neutrocyte, and lymphocyte in peripheral blood were (13.7±3.3)×10 9/L, (35.3±14.8)% and (57.2±15.1)% respectively before injury, (19.4±3.1)×10 9/L, (60.5±12.5)% and (33.6±14.2)% respectively at 3 hours after injury, and (20.6±3.6)×10 9/L, (63.6±13.0)% and (30.9±15.0)% respectively at 6 hours after injury. By contrast, the levels of white blood count and neutrocyte were significantly increased but the level of lymphocyte was significantly decreased at 3 and 6 hours after injury ( P<0.05 or 0.01); the levels of the above indicators showed no significant changes at 0 and 24 hours after injury (all P>0.05); the level of monocyte did not change significantly at all time points before and after injury (all P>0.05). The levels of PT-1, PT-INR, APTT, TT, PTA and FIB in the shock and vibration injury group did not change significantly at each time point before and after injury (all P>0.05). Conclusion:Cerebral cortex microvascular injury and disruption of blood-brain barrier can be initiated in the early stage of high-energy shock and vibration injury in goats, accompanied by the presence of central and peripheral inflammatory response.

Objective To explore the diagnosis ,treatment methods and clinical features of primary ureteral polyps.Methods Clinical data of 27 cases with primary ureteral polyps were analyzed retrospectively .The clinical features and treatment of this disease were analyzed .Results 7 cases were treated with polypectomy ,10 cases with basement fulguration by ureteroscopy operation or polyps-removing by ureter forceps ,4 cases with distal ureter resec-tion and termino-terminal anastomosis ,4 cases with lesions ureter resection and bilateral ureteric reimplantaion and 2 cases with nephrectomy due to nonfunctioning kidney .All cases were confirmed to be primary ureter polyp by pathology.All cases were followed up for 6-12 months with no recurrence and canceration ,only 1 case had ureteral stenosis.Conclusion Primary ureteral polyps is a benign disease with rare malignancy .The primary and effective treatment method is surgery which has few complications and good effect .

Objective To approach the methods and effects of internal fixation for Hoffa fracture. Methods A total of 26 patients with 26 condylar Hoffa fractures ( medial condylar fractures in 13patients and lateral condylar fractures in 13) treated from August 1993 to February 2010 were retrospectively analyzed.According to the Letenneur classification,there were 16 patients with type Ⅰ fractures,four with type Ⅱ fractures and six with type Ⅲ fractures.Among them,two patients were with open fractures and 24 with closed fractures.Surgical approaches including screw fixation in 21 patients and lateral support plate fixation in five were selected based on the fracture types and affected sides. Results All patients were followed up for 12.5-48 months (average 18 months),which showed fracture healing in all the patients within 3-4 months (average 3.5 months).Two patients had slight shift together with knee joint pain,ie,one patient had ROM of knee for 95 °,and one failed the functional exercise because of pain and had ROM of knee for 60° during follow up.No complications including infection,delayed union or bone necrosis occurred.According to Letenneur' s functional assessment system,the postoperative outcomes were excellent and good in 24 condyles,fair in one and poor in one. Conclusions Surgical treatment for Hoffa fractures is safe and effective,but the key point is to choose correct screw fixation position and orientation according to the fracture types and fracture fragment size.