OBJECTIVE To investigate the distribution and drug resistance of strains producing extended spectrum beta-lactamases (ESBLs) isolated from clinic samples and offer scientific basis for reasonable usage of antibioticsMETHODS ESBLs-producing strains isolated from Escherichia coli were identified by phenotypic comfirmatory test,drug resistance was analyzed by K-B method. RESULTS The positive rate of isolated ESBLs-producing E. coli strains was respectively 18.0%,20.3% and 28.4% in three years; that of ESBLs-producing strains isolated from urinary system was respectively 25.6%,29.0% and 39.0% in three years. The susceptibility to AMK and CFS was 70.4% and 85.2%,respectively in 2006. CONCLUSIONS The positive rate of ESBLs-producing strains and their resistance have been increasing in the near three years. so our clinic should pay attention to reasonable usage of antibiotic. AMK and CFS show significant antimicrobial activity for ESBLs-producing E. coli.

Objective To evaluate the effects of mechanical stretch preconditioning on pathological stretch-induced activation of nuclear factor kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3) signaling pathways in human type Ⅱ alveolar epithelial cells.Methods Human type Ⅱ alveolar epithelial cell line A549 cells cultured in vitro were randomly divided into 3 groups (n =24 each) using a random number table: control group (group Ⅰ), pathological stretch group (group Ⅱ), and mechanical stretch preconditioning group (group Ⅲ).In group Ⅰ , A549 cells were cultured routinely without receiving pathological stretch.In group Ⅱ , A549 cells were exposed to 20％ cyclic stretch at 0.3 Hz for 6 h.In group Ⅲ , A549 cells were exposed to 5％ cyclic stretch at 0.3 Hz for 60 min, and then exposed to 20％ cyclic stretch at 0.3 Hz for 6 h.After the end of the treatment, the cells were collected for determination of the cell viability (by methyl thiazolyl tetrazolium assay) and lactate dehydrogeuase (LDH)release (by colorimetric method).The concentrations of tumor necrosis factor-alpha (TNF-α),interleukin-8 (IL-8) and high mobility group box 1 (HMGB1) in the culture medium were detected using enzyme linked immunosorbent assay.The expression of total NF-κB, phosphorylated NF-κB, total STAT3 and phosphorylated STAT3 was detected using Western blot.The ratios of phosphorylated NF-κB to total NF-κB and phosphorylated STAT3 to total STAT3 were calculated to reflect the activation.Results Compared with group Ⅰ , the cell viability was significantly decreased, the amount of LDH released was increased, and the concentrations of TNF-α, IL-8 and HMGB1, and activation of NF-κB and STAT3 were increased in Ⅱ and Ⅲ groups.Compared with group Ⅱ , the cell viability was significantly increased, the amount of LDH released was decreased, and the concentrations of TNF-α, IL-8 and HMGB1, and activation of NF-κB and STAT3 were decreased in group Ⅲ.Conclusion The mechanism by which mechanical stretch preconditioning attenuates pathological stretch-induced damage to human type Ⅱ alveolar epithelial cells is related to inhibited activation of NF-κB and STAT3 signaling pathways.

Objective To evaluate the effects of intrathecal 2-PMPA on chronic inflammatory pain in rats . Methods Twenty four male Sprague-Dawley rats ,aged 4-6 months ,weighing 200-250 g ,were randomly divided into 3 groups (n=8 each) using a random number table :normal saline (NS) group ,complete Freund′s adjuvant (CFA ) group and N-acetylaspartylglutamate peptidase inhibitor 2-PMPA group (group 2-PMPA ) . Chronic inflammatory pain was induced by injecting 100μl of CFA into the plantar surface of the left hindpaw .Immediately after injection of CFA ,2-PMPA 100 μg was injected intrathecally once a day for 3 consecutive days in group 2-PMPA ,while the equal volume of NS was given instead of 2-PMPA in NS and CFA groups .The paw withdrawal latency to thermal nociceptive stimulus (TWL ) and paw withdrawal threshold (PWT ) to von Frey filament stimulation were measured before injection of CFA (baseline ,T1 ) and after the last injection of CFA (T2 ) .Then the rats were sacrificed and the L4 ,5 segments of the spinal cord were removed for determination of NR2B expression by Western blot .Results Compared with group NS ,TWL and PWT were significantly decreased at T2 and the expression of NR2B was up-regulated in CFA and 2-PMPA groups ( P<0.05 ) .Compared with group CFA ,TWL and PWT were significantly increased at T2 and the expression of NR2B was down-regulated in group 2-PMPA ( P<0.05) .Conclusion Intrathecal 2-PMPA can alleviate CFA-induced chronic inflammatory pain in rats ,and inhibition of NR2B expression in the spinal cord is involved in the mechanism .

Objective To investigate the influencing factors on serum homocysteine level in healthy retired-elderly people in Tianjin,in order to provide theoretical basis and guidance for clinical intervention therapy.Methods A total of 184 participants meeting the standard of Chinese healthy elderly people (2013) were selected from 1247 retired-elderly people who took healthy physical examination in three grade Ⅲ-A hospitals in Tianjin from June to August in 2014.They were divided into two groups based on plasma Hcy level:hyper-homocystinemia group (≥15 μmol/L) and normal plasma Hcy level group (＜15μmol/L).The influencing factors on plasma Hcy level were analyzed by multiple stepwise regression and logistic regression analysis.Results The proportion of healthy retired-elderly people accounted for 14.76 ％,with men at 82.61％ and women at 17.39 ％,mean age (78.37±6.88) years.The Hcy level was higher in healthy males than in healthy females [(16.90± 6.86) μmol/L vs.(12.89 ± 5.97) μmol/L,P＜0.005].The proportion of people with hyper-homocystinemia accounted for 45.65％,and the mean Hcy concentration was (21.39±6.98) μmol/L.The age of people with hyper-homocystinemia was higher than that with normal Hcy [(80.58±6.09) years vs.(76.56±7.04) years,P＜0.005].There were no statistically significant differences in blood pressure,lipid and blood glucose levels and the proportion of patients with coronary heart disease,hypertension,type 2 diabetes mellitus,gout,periodontitis and other diseases between the two groups (all P＞0.05).Spearman correlation analysis showed that the level of serum Hcy was positively correlated with serum uric acid levels (P=0.000).Multiple stepwise regression and logistic regression analysis showed that age,gender and serum uric acid level were risk factors for plasma Hcy level in healthy elderly people.Conclusions Age,gender and serum uric acid level are risk factors for serum Hey level in healthy elderly people.

Objective To evaluate the relationship between the shedding of syndecan-4(SDC-4) in lung tissues and ventilator-induced lung injury in rats. Methods Thirty pathogen-free healthy adult male Wistar rats, weighing 220-250 g, were divided into 3 groups(n=10 each)using a random number table:control group(group C), mechanical ventilation with traditional tidal volume(VT)group(group T-VT) and mechanical ventilation with high VTgroup(group H-VT). The animals were anesthetized with pento-barbital sodium and tracheostomized. The rats kept spontaneous breathing in group C. The rats were me-chanically ventilated for 4 h with the VTset at 6 ml∕kg in group T-VT and with the VTset at 40 ml∕kg in group H-VT. Blood samples were collected immediately after the end of ventilation for measurement of serum SDC-4 concentrations by enzyme-linked immunosorbent assay. The left lung was lavaged, and broncho-alveolar lavage fluid was collected for determination of interleukin-1beta(IL-1β), IL-18, tumor necrosis factor-alpha and SDC-4 concentrations by enzyme-linked immunosorbent assay. The lungs were removed for determination of the wet to dry weight ratio and expression of SDC-4 protein and mRNA in lung tissues(by Western blot and real-time polymerase chain reaction, respectively)and for examination of the pathological changes. The lung injury scores were recorded. Results Compared with group C, the wet to dry weight ratio, lung injury scores, concentrations of IL-1β, IL-18, tumor necrosis factor-alpha and SDC-4 in bron-cho-alveolar lavage fluid and concentrations of SDC-4 in serum were significantly increased, the expression of SDC-4 mRNA was up-regulated, and the expression of SDC-4 was down-regulated in group H-VT(P<005), and no significant change was found in the parameters mentioned above in group T-VT(P>005).Marked pathological changes of lung tissues were found in group H-VT. Conclusion A large shedding of SDC-4 in lung tissues may be involved in the pathophysiological mechanism of ventilatior-induced lung injury in rats.

Objective To evaluate the accuracy of respiratory variations of internal jugular vein (IJV) in monitoring fluid responsiveness in patients undergoing radical gastrectomy for gastric cancer.Methods Fifty American Society of Anesthesiologists physical status Ⅰ or Ⅱ patients of both sexes,aged 40-64 yr,scheduled for elective radical gastrectomy for gastric cancer,were enrolled in this study.Before induction of anesthesia,the hemodynamic parameters such as heart rate,central venous pressure,cardiac index,stroke volume index (SVI),stroke volume variation and respiratory variation of IJV were recorded after haemodynamics was stable and were recorded again at 10 min after endotracheal intubation,and a loading dose of 6％ 130/0.4 hydroxyethyl starch 7 ml/kg was infused over 15 min.The parameters mentioned above were recorded within 5 min after loading dose.Patients were divided into 2 groups according to the percentage of increase in SVI (△SVI) after volume expansion:△SVI≥ 15％ was considered to be a positive response (responder group) and △SVI＜15％ was considered to be a negative response after volume expansion (non-responder group).Results The area under the receiver operating characteristic curve of respiratory variations of IJV in monitoring fluid responsiveness and 95％ confidence interval were 0.852 (0.744-0.961).Respiratory variation of IJV 24.6％ was considered as the cut-off value and used to monitor fluid responsiveness,and the sensitivity and specificity were 67.6％ and 92.3％,respectively.Conclusion Respiratory variation of IJV can be considered as an effective index in monitoring fluid responsiveness in the patients undergoing radical gastrectomy for gastric cancer.

Objective:To evaluate the effect of individualized positive end-expiratory pressure (PEEP) titration based on open-lung strategy on the intraoperative thoracic fluid content (TFC) in elderly patients undergoing transurethral ultrasound-guided laser-induced prostatectomy (TULIP).Methods:Eighty-six American Society of Anesthesiologists Physical Status classification Ⅱ or Ⅲ, patients, aged 65-80 yr, with body mass index of 18-28 kg/m 2, scheduled for elective TULIP, were divided into 2 groups ( n=43 each) by the random number table method: fixed PEEP group (group C) and individualized PEEP titration group (group P). PEEP was set at 4 cmH 2O after routine mechanical ventilation in group C. Patients underwent pulmonary recruitment maneuvers combined with individualized PEEP titration during surgery in group P. TFC was measured using a non-invasive cardiac output monitor at 5 min after tracheal intubation (T 0), 30 min after PEEP titration and ventilation (T 1), 5 min before surgery (T 2), and 5 min before leaving the recovery room (T 3). Cardiac output, oxygenation index and stroke volume index were recorded from T 0-T 2, arterial blood gas analysis was simultaneously performed to record peak airway pressure and dynamic lung compliance, and oxygenation index was calculated. The duration of postanesthesia care unit stay, pulmonary complications within 7 days after surgery, and length of hospital stay were also recorded. Results:Eighty-three patients were finally included, with 42 in group C and 41 in group P. Compared with group C, TFC was significantly decreased at T 1-T 3, cardiac index, cardiac output and stroke volume index were decreased at T 1, dynamic lung compliance, PaO 2 and oxygenation index were increased at T 1 and T 2, PaCO 2 was decreased, the incidence of postoperative pulmonary complications was reduced, and the duration of postanesthesia care unit stay and postoperative length of hospital stay were shortened in group P ( P<0.05). Conclusions:Individualized PEEP titration based on open-lung strategy can effectively decrease TFC and improve intraoperative oxygenation and prognosis in elderly patients undergoing TULIP.

Objective To assess the accuracy and feasibility of respirophasic variation in carotid artery blood flow peak velocity (△Vpeak-CA) as predictors of fluid responsiveness in laparoscopic surgery.Methods Fifty-five patients undergoing laparoscopic surgeries,29 males and 26 females,aged 45-75 years,ASA physical status Ⅰ-Ⅲ,with body mass index 20-24 kg/m2,were enrolled.When intra-abdominal pressure was steady at the level of 13-15 mm Hg,6％ hydroxyethylstarch (HES 130/0.4) 500 ml was infused at the speed of 7 ml/kg within 20 minutes.After volume expansion,subjects were classified as responders (group R,n =32) if cardiac index increased (△CI) was≥ 15％ and no responders (group NR,n =23) as △CI＜15％.The receiver operating characteristic curve (ROC) curve for △Vpeak-CA in determining the volume expansion responsiveness was plotted,and the diagnostic threshold was determined.The area under curve (AUC) and 95 ％ confidence interval (CI) was calculated.Cardiac index (CI),△Vpeak-CA and stroke volume variation (SW) were independently recorded at 5 minutes after induction (T1),5 minutes after intra-abdominal pressure were stable at the level of 13-15 mm Hg (T2) and 5 minutes after volume expansion (T3).Results △Vpeak-CA is highly negatively correlated with CI (r=-0.843,P＜0.001).The results of ROC curve analysis showed,△Vpeak-CA threshold discriminated between responders and non-responders with a sensitivity of 81.3％ and a specificity of 91.3％,and the AUC was 0.884 (95％ CI 0.793-0.975).Conclusion △Vpeak-CA seems to be a highly feasible and reliable predictor for fluid responsiveness in laparoscopic surgery patients.

Objective To evaluate the accuracy of respirophasic variation in carotid artery blood flow peak velocity(ΔVpeak-CA)in predicting fluid responsiveness in the patients undergoing surgery in the prone position. Methods Forty-three American Society of Anesthesiologists physical status Ⅰ-Ⅲ pa-tients of both sexes, aged 45-75 yr, with body mass index of 20-25 kg∕m2, scheduled for elective posteri-or approach lumbar surgery, were enrolled in the study.After induction of anesthesia, hydroxyethyl starch 130∕0.4 sodium chloride injection 7 ml∕kg was intravenously infused over 20 min when the patients were in the prone position.Subjects were classified as responders if stroke volume index increased≥15% after vol-ume expansion.The receiver operating characteristic curve for ΔVpeak-CA in determining positive fluid re-sponsiveness was drawn. Results The results of receiver operating characteristic curve analysis showed that: the cut-off value of ΔVpeak-CA in predicting positive fluid responsiveness was 7.94%, sensitivity 81.8%, specificity 70.0%, and the area under the curve(95% confidence interval)was 0.818 (0.378-0.757). Conclusion Respirophasic ΔVpeak-CA can accurately predict fluid responsiveness in the patients undergoing surgery in the prone position.

Objective:To evaluate the effect of botulinum neurotoxin A (BoNT/A) on prevention of chronic migraine (CM) in mice and explore the potential mechanism.Methods:Twenty-four male C57BL/6 mice were randomly divided into control group, nitroglycerin (NTG) group, and BoNT/A+NTG group ( n=8). Mice in the latter two groups were intraperitoneally injected with 10 mg/kg NTG on the 1 st, 3 rd, 5 th, 7 th and 9 th d of experiments to establish CM models. Mice in the BoNT/A+NTG group were injected with 0.18 U/100 μL BoNT/A one h before the first injection of NTG. Mice in the control group were injected with the same dose of normal saline. Basal mechanical withdrawal threshold (MWT) and evoked MWT 2 h after NTG in the facial and hindpaw regions on the 1 st, 3 rd, 5 th, 7 th and 9 th d of experiments were evaluated by von Frey filament test. The motor function of mice 2 h after NTG injection was tested by rotarod test on the 1 st, 3 rd, 5 th, 7 th and 9 th d of experiments. On 9 th d of experiments, the mice were sacrified; the calcitonin gene-related peptide (CGRP), synaptosomal-associated protein 25 (SNAP25), glial fibrillary acidic protein (GFAP) and TRP channel protein expressions in the trigeminal ganglia (TG) and trigeminal nucleus caudalis (TNC), and NOD-like receptor protein 3 (NLRP3) inflammatory factor pathway-related protein expressions in TNC were detected by Western blotting; real-time quantitative PCR (RT-qPCR) was used to detect the NLRP3 inflammatory factor pathway-related mRNA expressions in TNC. The CGRP expression in TNC was detected by immunofluorescent staining. Results:(1) As compared with the control group, the NTG group had significantly decreased basal facial MWT on the 7 th and 9 th d of experiments ( P<0.05); as compared with the NTG group, the BoNT/A+NTG group had significantly increased basal facial MWT on the 7 th and 9 th d of experiments ( P<0.05). As compared with the control group, the NTG group had significantly decreased evoked facial MWT on the 5 th and 9 th d of experiments ( P<0.05); as compared with the NTG group, the BoNT/A+NTG group had significantly increased evoked facial MWT on the 5 th and 9 th d of experiments ( P<0.05). As compared with the control group, the NTG group had significantly decreased basal and evoked MWT in the hindpaw regions on the 3 rd, 5 th, 7 th and 9 th d of experiments ( P<0.05); as compared with the NTG group, the BoNT/A+NTG group had significantly increased basal and evoked MWT in the hindpaw regions on the 3 rd, 5 th, 7 th and 9 th d of experiments ( P<0.05). (2) There was no significant difference in running time on rotarod among the three groups ( P>0.05). (3)Western blotting results showed that as compared with those in the control group, the CGRP and SNAP25 protein expressions were significantly increased in TG of the NTG group ( P<0.05); and those in the BoNT/A+NTG group were significantly decreased as compared with those in the NTG group ( P<0.05). As compared with those in the control group, the CGRP and NLRP3 protein expressions were significantly increased in TNC of NTG group ( P<0.05); and those in the BoNT/A+NTG group were significantly decreased as compared with those in the NTG group ( P<0.05). (4)RT-qPCR results showed that as compared with that in the control group, the IL-1β mRNA expression in TNC of the NTG group was significantly increased ( P<0.05), and that in the BoNT/A prevention group was statistically decreased as compared with that in the NTG group ( P<0.05). (5) Immunofluorescent staining results showed that as compared with that in the control group, the CGRP expression in TNC of the NTG group was significantly increased, and that in the BoNT/A+NTG group was significantly decreased as compared with that in the NTG group ( P<0.05). Conclusion:BoNT/A can reduce the SNAP25 expression in TG, reduce the CGRP release in TG and TNC, and prevent CM onset; BoNT/A can regulate NLRP3 level in TNC.