Catalase is widely used in the food, medical, and textile industries. It possesses exceptional properties including high catalytic efficiency, high specificity, and environmental friendliness. Free catalase cannot be recycled and reused in industry, resulting in a costly industrial biotransformation process if catalase is used as a core ingredient. Developing a simple, mild, cost-effective, and environmentally friendly approach to immobilize catalase is anticipated to improve its utilization efficiency and enzymatic performance. In this study, the catalase KatA derived from Bacillus subtilis 168 was expressed in Escherichia coli. Following separation and purification, the purified enzyme was prepared as an immobilized enzyme in the form of enzyme-inorganic hybrid nanoflowers, and the enzymatic properties were investigated. The results indicated that the purified KatA was obtained through a three-step procedure that included ethanol precipitation, DEAE anion exchange chromatography, and hydrophobic chromatography. Then, by optimizing the process parameters, a novel KatA/Ca₃(PO₄)₂ hybrid nanoflower was developed. The optimum reaction temperature of the free KatA was determined to be 35 ℃, the optimum reaction temperature of KatA/Ca₃(PO₄)₂ hybrid nanoflowers was 30-35 ℃, and the optimum reaction pH of both was 11.0. The free KatA and KatA/Ca₃(PO₄)₂ hybrid nanoflowers exhibited excellent stability at pH 4.0-11.0 and 25-50 ℃. The KatA/Ca₃(PO₄)₂ hybrid nanoflowers demonstrated increased storage stability than that of the free KatA, maintaining 82% of the original enzymatic activity after 14 d of storage at 4 ℃, whereas the free KatA has only 50% of the original enzymatic activity. In addition, after 5 catalytic reactions, the nanoflower still maintained 55% of its initial enzymatic activity, indicating that it has good operational stability. The K_m of the free KatA to the substrate hydrogen peroxide was (8.80±0.42) mmol/L, and the k_cat/K_m was (13 151.53± 299.19) L/(mmol·s). The K_m of the KatA/Ca₃(PO₄)₂ hybrid nanoflowers was (32.75±2.96) mmol/L, and the k_cat/K_m was (4 550.67±107.51) L/(mmol·s). Compared to the free KatA, the affinity of KatA/Ca₃(PO₄)₂ hybrid nanoflowers to the substrate hydrogen peroxide was decreased, and the catalytic efficiency was also decreased. In summary, this study developed KatA/Ca₃(PO₄)₂ hybrid nanoflowers using Ca²⁺ as a self-assembly inducer, which enhanced the enzymatic properties and will facilitate the environmentally friendly preparation and widespread application of immobilized catalase.
Catalase ; Nanostructures/chemistry* ; Hydrogen Peroxide/metabolism* ; Enzymes, Immobilized/chemistry* ; Catalysis

Effective methods for visualizing neurovascular morphology are essential for understanding the normal spinal cord and the morphological alterations associated with diseases. However, ideal techniques for simultaneously imaging neurovascular structure in a broad region of a specimen are still lacking. In this study, we combined Golgi staining with angiography and synchrotron radiation micro-computed tomography (SRμCT) to visualize the 3D neurovascular network in the mouse spinal cord. Using our method, the 3D neurons, nerve fibers, and vasculature in a broad region could be visualized in the same image at cellular resolution without destructive sectioning. Besides, we found that the 3D morphology of neurons, nerve fiber tracts, and vasculature visualized by SRμCT were highly consistent with that visualized using the histological method. Moreover, the 3D neurovascular structure could be quantitatively evaluated by the combined methodology. The method shown here will be useful in fundamental neuroscience studies.

Effective methods for visualizing neurovascular morphology are essential for understanding the normal spinal cord and the morphological alterations associated with diseases. However, ideal techniques for simultaneously imaging neurovascular structure in a broad region of a specimen are still lacking. In this study, we combined Golgi staining with angiography and synchrotron radiation micro-computed tomography (SRμCT) to visualize the 3D neurovascular network in the mouse spinal cord. Using our method, the 3D neurons, nerve fibers, and vasculature in a broad region could be visualized in the same image at cellular resolution without destructive sectioning. Besides, we found that the 3D morphology of neurons, nerve fiber tracts, and vasculature visualized by SRμCT were highly consistent with that visualized using the histological method. Moreover, the 3D neurovascular structure could be quantitatively evaluated by the combined methodology. The method shown here will be useful in fundamental neuroscience studies.
Animals ; Imaging, Three-Dimensional ; Mice ; Neural Networks, Computer ; Spinal Cord/diagnostic imaging* ; Synchrotrons ; X-Ray Microtomography

Objective:To determine initial concentrations of ozonated water under different temperatures,attenuation rules ofozonated water under the room temperature (25 ℃),and to inspect the effects ofozonated water under different concentrations on common microorganisms.Methods:The online test method and the plate cultivation method were employed to check the concentrations and killing rates on common microorganisms of ozonated water produced by HZ-2601 B Ozone Water Generating Instrument.Results:The initial concentrations of ozonated water at 20,25,30,35,and 40 ℃ were 4.38,4.26,3.12,2.76,and 1.31 mg/L,respectively.The ozonated water was rapidly attenuated at first 10 min.The concentration ofozonated water still remained at 1.06 mg/L and 0.37 mg/L at 25 and 30 ℃ after 30 min.The average killing rates for Pseudornonas aeruginosa,Escherichia coli,Staphylococcus aureus,methicillin-resistant Staphylococcus aureus,and Candida albicans in 1.0 mg/L ozonated water for 1 min were 99％,100％,100％,100％,and 100％,respectively.The average killing rates of Escherichia coli,Staphylococcus aureus,methicillin-resistant Staphylococcus aureus,Pseudomonas aeruginosa,and Candida albicans in 0.3 mg/L ozonated water for 1 min were 100％,100％,100％,95％,and 92％,respectively.Conclusion:The initial concentrations of ozonated water produced by HZ-2601 B Ozone Water Generating Instrument decrease with the increase of temperature.Ozonated water under 20-30 ℃ has good sterilization effect on common microorganisms.

Objective To observe the application effects of expander between collarbone and first rib space in Peripherally Inserted Central Catheter (PICC ).Methods A total of 1 20 PICC patients with chemotherapy were recruited from April 201 4 to April 201 5 and were divided into control group (54 cases, routine tube)and observation group (66 cases,self-designed expander between collarbone and first rib space) according to the method of random number table.And then,we compared the success rate of tubing and puncturing at once,operation time,catheter misplacement,mechanical phlebitis,the incidence of infection between two groups.Results The success rates of tubing and puncturing at once,operation time in observation group were better than those in control group with significant differences (P <0.05).There were statistically significant differences in catheter misplacement,mechanical phlebitis,the incidence of infection of patients between two groups (P <0.05).Conclusions The expander between collarbone and first rib can effectively decrease the incidence of complications and improve the effects of PICC.

Objective:To construct a p53-fused dual luciferase reporter and to test whether this reporter can mimic wild-type p53 activities in a high-throughput screen.Methods:A restriction endonuclease site was added to each terminus and the stop codon of the wild-type full-length p53 open reading frame (ORF) was removed by PCR. A restriction endonuclease site was added to each terminus and the start codon of the ifrelfy luciferase ORF was removed by PCR. The two modified ORFs were inserted upstream of the IRES-induced renilla luciferase ORF in a CMV-derived vector. hTe p53 fusion protein was expressed in cells to test its MDM2-mediated degradation, subcellular localization, and induction of p53-responsive promoter.
Results:hTe p53-fused dual luciferase reporter was successfully constructed. Atfer transfection into the host cells, the reporter expressing the p53 fusion protein that was degraded by oncoprotein MDM2, was mainly located inside the nucleus, and induced the p53-responsive promoter, respectively.
Conclusion:hTe p53-fused dual luciferase reporter (p53FL/IRES/RL) can identify modulators of P53 protein level in a high-throughput screen of genetic or chemical libraries.

OBJECTIVETo investigate the abnormal changes in the testes and semen parameters in patients with varicose veins and analyze the possible relationship between clinical varicocele and infertility.

METHODSWe retrospectively reviewed the records of 172 male patients consulting for varicocele in our hospital since 2003. All these patients were examined for the size of the testes with scrotal ultrasound. The semen samples of the patients with varicocele except for 5 under the age of 17 years were collected and analyzed, using the data of semen analyses of 163 healthy young male volunteers (aged 18-29 years) as control.

RESULTSAll the 172 patients had left-sided varicose veins. Sixty-three patients were found to have bilateral varicocele, and in most of them, the clinical grades of the left-sided varicose veins were higher than those of the right-sided ones. The mean volume of the left testis of the patients was 10.99∓3.71 ml, significantly smaller than that of the right one (11.86∓4.05 ml, P<0.01). The physiochemical indices of the patients, including the voiding volume, semen pH, liquefaction time and sperm concentration, were normal or similar with those of the healthy volunteers (P>0.05). Almost all the patients sperm motility and viability were significantly lower than those of the healthy volunteers (P<0.05). In addition, no significant difference was found in the sperm density, motility or viability between the patients with unilateral and bilateral varicocele (P>0.05).

CONCLUSIONVaricocele may decrease the testicular volume. Both unilateral and bilateral varicocele may have an effect on the bilateral testes to cause possible functional impairment of the testes manifested by decreased sperm motility and viability.

Adolescent ; Adult ; Child ; Humans ; Infertility, Male ; etiology ; Male ; Middle Aged ; Retrospective Studies ; Semen ; Sperm Count ; Sperm Motility ; Testis ; physiopathology ; Varicocele ; complications ; physiopathology ; Young Adult

OBJECTIVE: To compare the safety and efficacy of prone and modified recumbent positions on minimal invasive percutaneous nephrolithotomy. METHODS: A total of 62 patients with upper urinary calculi were grouped into two groups, one of which consisted of 27 patients who underwent the minimal invasive percutaneous nephrolithotomy with modified recumbent position, and the other 35 patients with prone position. There was no significant statistical difference in the age, gender and complications between the two groups before surgery (P>0.05). Duration of and blood loss during surgery, complications in the perioperative period, and the length of postoperative hospital stay were all recorded. The data were analyzed by SPSS 13.0. RESULTS: Surgery was successful in all cases. There was no failure to puncture nor need to resort to open surgery. Average operation duration for the modified recumbent position group was (85.1± 25.3) min vs (97.2±30.6) min for the prone position group. Mean blood loss during the operation was (117.5± 49.7) mL vs (149.3±53.1) mL. There were no severe complications during and after surgery in the modified recumbent position group. In the prone position group, s one patient suffered pneumothorax during the operation and two suffered selective renal artery embolization because of massive hemorrhaging following the operation. There were significant differences in blood loss during surgery, in complications during the perioperative period, and in length of postoperative stay in hospital (P<0.05) between the two groups. CONCLUSION The patients are safer and more easily tolerate the minimal invasive percutaneous nephrolithotomy in the modified recumbent position than in the prone position, though the treatment efficacy of these two kinds of operation is similar. It is recommended that the modified recumbent position should be used generally in the percutaneous nephrolithotomy.
Adult ; Aged ; Female ; Humans ; Kidney Calculi ; surgery ; Male ; Middle Aged ; Minimally Invasive Surgical Procedures ; methods ; Nephrostomy, Percutaneous ; methods ; Posture ; Prone Position ; Supine Position ; Ureteral Calculi ; surgery

OBJECTIVE: To construct short hairpin RNA interfering expression vector of TDRG1,and detect the specific interfering effect of TDRG1-shRNA expression vector on NTERA-2 cells. METHODS: Oligos for short hairpin RNA targefing for TDRG1 were designed and connected to the expression vector pGPU6/GFP/Neo to construct the TDRG1 shRNA expression vector. The recombinant plasmid TDRG1-shRNA486, TDRG1-shRNA738, TDRG1-shRNA921 and lipofectamine ™2000 were used to generate and transfect shRNA into NTERA-2 cells. Expression of TDRG1 mRNA was assayed by RT-PCR. RESULTS: TDRG1-shRNA expression vector was successfully constructed. TDRG1-shRNA486 was more effective in the suppression of TDRG1 with significant reduction of TDRG1 mRNA. CONCLUSION TDRG1-shRNA can interfere the expression of TDRG1 in NTERA-2 cells.
Cell Line, Tumor ; Genetic Vectors ; Humans ; RNA Interference ; RNA, Messenger ; RNA, Small Interfering ; Transfection