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As self-subunit swapping chaperones or metallochaperones, the activators assist nitrile hydratases to take up metal ions and they are essential for active expression of nitrile hydratases. Compared with nitrile hydratases, the activators have a low sequence identity. Study of the activation characteristics and the relationships between structures and functions of the activators is of great significance for understanding the maturation mechanism of nitrile hydratase. We co-expressed low-molecular-mass nitrile hydratase (L-NHase) from Rhodococcus rhodochrous J1 with four heterologous activators respectively and determined their activation abilities. Then we made sequence analysis and structure modelling, and studied the functions of the important domains of the activators. Results showed that all four heterologous activators could activate L-NHase, however, the specific activities of L-NHases were different after activation. L-NHase showed the highest specific activity after being activated by activator A, which was 97.79% of that of the original enzyme, but the specific activity of L-NHase after being activated by activator G was only 23.94% of that of the original enzyme. Activator E and activator G had conserved domains (TIGR03889), and deletion of their partial sequences resulted in a substantial loss of activation abilities for both activators. Replacing the N-terminal sequence of activator G with the N-terminal sequence of activator E, and adding the C-terminal sequence of activator E to the C-terminus of activator G could increase the specific activity of L-NHase by 178.40%. The activation by nitrile hydratase activators was universal and specific, and the conserved domains of activators were critical for activation, while the N-terminal domain and C-terminal domain also had important effects on activation.
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Objective To research the intervention effect of the ABCDE Bundle in mechanically ventilated patients. Methods A prospective randomized controlled trail (RCT) was selected 84 mechanically ventilated patients aged 22-45 years in the ICU of respiratory and severe medical center of the affiliated hospital of Logistics University of PAP from January to December in 2016. The research samples were randomly divided into intervention group (n=42) and control group (n=42). Samples were chosen to compare the difference of basic situation, ICU length of stay, 28-day hospital survival rate and the incidence of delirium between the patients of intervention group and control group. Results The average ICU hospitalization time in the intervention group was (11.76± 5.15) days, while that in the control group was (17.64 ± 8.04) days, and the difference between the 2 groups was statistically significant (t=3.99, P<0.01). The 4-week survival rate and delirium incidence rate in intervention group were 90.48% (38/42) and 66.67% (28/42) respectively, while those in control group were 71.43% (30/42) and 40.48% (17/42) respectively, and the difference between 2 groups was statistically significant (χ2=4.94, 5.79, P<0.05). Conclusion The application of bundles of care strategy could reduce the incidence of delirium and improve the clinical outcome of mechanically ventilated patients.
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AIM: To explore the role of purinergic signaling mediated by ATP in the Alzheimer ’ s disease (AD)-related colon motility disorder and its related molecular mechanisms .METHODS:(1)Clinical trials:AD patients in our hospital were collected and studied .Radioimmunoassay was used for the determination of plasma motilin (MTL), cholecystokinin (CCK), vasoactive intestinal peptide (VIP) and nitric oxide (NO), and high-performance liquid chroma-tography ( HPLC) was applied to test the level of adenosine triphosphate ( ATP) .The patients were assessed by neuropsy-chology and scored accordingly .( 2 ) In animal experiments , AD mice received Morris water maze test , and the spatial learning and memory function were evaluated .The plasma levels of MTL , CCK, VIP and NO were examined by radioimmu-noassay , and the level of ATP was measured by HPLC .Choline acetyltransferase ( ChAT ) , VIP, nitric oxide synthase ( NOS) and ATP synthase were detected by immunohistochemistry .Western blot and immunohistochemistry were used to detect the expression of P2Y receptor.(3) In vitro, organ bath was applied to observe the effect of α,β-methylene ATP (α,β-MeATP), an agonist of P2Y receptor, on both spontaneous and electrically evoked contraction of colonic smooth muscle strip, and the technique of intracellular microelectrode was applied to observe the effect of α,β-MeATP on the membrane potential of colonic smooth muscle cells .RESULTS:Compared with control group , the levels of MTL and CCK were decreased (P<0.01), and the levels of NO and ATP were increased (P<0.05 or P<0.01), while the VIP level was not changed.Mini-Mental State Examination (MMSE) score was decreased (P<0.05), Alzheimer’s Disease Assess-ment Scale-Cognitive Subscale (ADAS-Cog) score, Neuropsychiatric Inventory (NPI) score and Alzheimer’s Disease Co-operative Study-Activities of Daily Living Scale ( ADCS-ADL ) were all increased as compared with control group ( P <0.01).The 4~6 d escape latency of APP/PS1 AD mice was significantly prolonged (P<0.05), and the space explora-tion ability distinctly reduced (P<0.05).In AD mice, the levels of MTL and CCK were decreased (P<0.01), and the levels of NO and ATP were increased (P<0.05 or P<0.01), while the VIP level was not changed .The protein expres-sion of colonic ATP synthase was significantly increased (P<0.05), but the expression of ChAT, VIP and NOS was not changed.The expression of P2Y receptor was increased (P<0.01).The results of in vitro experiment displayed that α,β-MeATP, from 20 μmol/L to 100 μmol/L, inhibited the spontaneous contraction of colonic smooth muscle strip in the nor-mal mice and AD mice ( P<0.05 or P<0.01 ) , and this inhibition was reversed by Na +channel inhibitor tetrodotoxin (TTX) (P<0.05 or P<0.01).In addition, the effect of α,β-MeATP at 100μmol/L on the AD mice was more obvious than that on the normal mice (P<0.05), and this inhibition was also antagonized by TTX (P<0.05 or P<0.01), pro-minent in AD group as compared with control group (P<0.05).In 10 Hz electrically evoked contraction of colonic smooth muscle strip,α,β-MeATP inhibited both the normal and AD mice (P<0.05 or P<0.01), while the inhibition was more obvious in the AD mice at the concentration of 40μmol/L or 100μmol/L (P<0.05 or P<0.01).CONCLUSION:AD patients and AD mice are accompanied by decreased MTL and CCK levels , and enhanced NO level , thus inducing colonic motor dysfunction along with AD .Meanwhile, ATP in plasma, purinergic neurons , and P2Y receptor expression are in-creased in the AD mice .Purinergic signaling mediated by ATP inhibits colonic smooth muscle strip contraction and further paralyzes the colonic movement function in AD .
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Objective On patients with mechanical ventilation spontaneous breathing trial (SBT) success, out of breath machine smoothly pulled out after endotracheal intubation for active airway moist sequential therapy of clinical new method and new technology. Methods Between January 2013 and May 2014 respiratory endotracheal intubation implementation of mechanical ventilation with intensive medicine successful withdraw machine pulled out of 135 patients with tracheal intubation, they were divided into group A(68 cases) and group B(67 cases) by random digits table method. The patients in group A were treated with buoy type oxygen device, group B with active airway moist heat treatment unit. The breathing rate, PaO2, SpO2, heart rate, Clinical Pulmonary Infection Score(CPIS) were measured after 72 h of pull out endotracheal intubation in two groups. Sputum viscosity was evaluated by Airway Secretions Score before pull out endotracheal intubation and after 24, 48, 72 h of pull out endotracheal intubation in two groups. Results There were no significant differences between two groups in gender, age, clinical diagnosis, mechanical ventilation time, acute physiology and chronic health evaluation systemⅡrating etc (P>0.05). The breathing rate, heart rate and CPIS score respectively (20.94 ± 0.89), (80.79±4.67) times/min and (7.13 ± 2.54) points after 72 h of pull out endotracheal intubation in group B, and (24.12 ± 0.97), (86.32 ± 5.12) times/min and (8.79±3.56) points in group A, and there were significant differences(t=5.113, 7.298, 5.597, all P0.05). After 24, 48 and 72 h of pull out endotracheal intubation, group B of patients with sputum viscosity was suitable in group A (Z=-2.684,-2.870,-2.771, all P < 0.01). Conclusions Mechanical ventilation in patients with ventilator buoy type oxygen device for the pull out after endotracheal intubation success does not favor the sputum drainage, improve patients with dyspnea and hypoxemia is not obvious. By positive airway plus temperature humidity to sequential therapy is helpful to correct hypoxemia, improve the patients' respiratory function, reduce the breathing difficulties, reduce sputum viscosity, promote the airway drainage unblocked, shortening the time of lung infection.
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Objective To investigate the expression of mutant p53,Ki-67,ER and PR in uterine endometrial carcinoma and uterine serous carcinoma,and explore their significance in differential diagnosis.Methods The samples including 37 cases of uterine endometrial carcinoma and 37 cases of uterine serous carcinoma were analyzed.The expression of mutant p53,Ki-67,estrogen receptor and progesterone receptor were performed by using the immunocytochemical (IHC) EnVision system.Data were analyzed with SPSS 11.5 statistic software.Results The positive rate of mutant p53 in uterine endometrial carcinoma was statistically lower than that in uterine serous carcinoma [21.62 % (8/37) vs 64.86 % (24/37) (P < 0.01)].The positive rate of Ki-67 in uterine endometrial carcinoma was statistically lower than that in uterine serous carcinoma [37.84 % (14/37) vs 70.27 % (24/37) (P < 0.01)].The positive rate of estrogen receptor in uterine endometrial carcinoma was statistically higher than that in uterine serous carcinoma [78.38 % (29/37) vs 32.43 % (12/37) (P < 0.01)].The positive rate of progesterone receptor in uterine endometrial carcinoma was statistically higher than that in uterine serous carcinoma [75.67 % (28/37) vs 29.73 % (11/37) (P < 0.01)].Conclusions The expression of mutant p53 and Ki-67 are higher in uterine serous carcinoma.The expression of estrogen receptor and progesterone receptor are higher in uterine endometrial carcinoma.Combined detection of mutant p53,Ki-67,ER and PR has important significance in screening and preventing uterine endometrial carcinoma and uterine serous carcinoma.