Effects of simulated microgravity on the phenotype of extensively drug-resistant Acinetobacter baumannii exstracted from sputum specimens of elderly patients with hospital-acquired pneumonia / 中华老年医学杂志

Objective:To investigate the effects of simulated microgravity on the phenotype of extensively drug-resistant Acinetobacter baumannii extracted from sputum specimens of elderly patients with hospital-acquired pneumonia. Methods:A strain of A. baumannii grown in simulated microgravity was constructed by a three-dimensional rotary cell culture system, and a strain of A. baumannii grown in normal gravity was prepared as a control group.The growth rates of the two strains were detected by the Bioscreen system, colony numbers were measured by the plate colony-counting method, oxidative stress was analyzed by observing the survival rate in phosphate buffer saline(PBS) with 5 mmol/L H 2O 2, biofilm formation ability was determined by crystal violet staining, and antibiotic susceptibility was measured by the K-B method. Results:Compared with the normal gravity strain, the simulated microgravity strain was associated with a significantly slower growth rate, especially after 10 h( P<0.05), a decreased number of bacterial colonies[(2.33±0.61)×10 13CFU/L vs.(4.87±0.63)×10 13CFU/L, t=4.865, P=0.040], lower survival rates in PBS solution with H 2O 2[(51.43±0.97)% vs.(56.53±2.54)%, t=4.715, P=0.042], reduced biofilm formation ability( A570), [(0.449±0.014) vs.(0.506±0.024), t=8.692, P=0.013], and an increased inhibition zone diameter of amikacin[(15.17±0.21) mm vs.(13.77±0.15) mm, t=6.725, P=0.021]. Conclusions:Simulated microgravity changes the growth rate, biofilm formation ability, oxidative stress and antibiotic susceptibility of extensively drug-resistant A. baumannii, potentially providing a new treatment strategy for extensively drug-resistant A. baumannii-associated hospital-acquired pneumonia in the elderly.

Increased inflammatory reaction in tail-suspension mice infected by K.pneumoniae from spaceflight / 军事医学

Objective To explore the changes in inflammatory reactions in tail-suspension mice infected by Klebsiella pneumoniae from spaceflight.Methods Tail suspension was used to simulate the physiological effects of microgravity.C57BL/6 mice were randomly divided into control (Con),control+K.pneumoniae T16-169 (Con+T16-169),tail suspension (TS) and tail suspension+K.pneumoniae T16-169 (TS+T16-169) groups.The level of inflammatory cytokines TNF-α,IL-6 and IL-1β mRNA in lung tissue and the plasma cytokine concentration were detected by RT-qPCR and xMAP technology,and HE staining was used to represent the morphological changes in lung tissue.Results Compared with the control group,the expression of inflammatory cytokines in lung tissue and plasma concentrations of all experimental groups were increased,and the difference in TS+T16-169 group was the most significant (P<0.01 or P<0.001).HE staining showed that the lung tissues in Con+T16-169 and TS+T16-169 groups were damaged in different degrees,and the damage of TS+T16-169 group was the most serious.Conclusion The K.pneumoniae from spaceflight significantly increases the expression of inflammatory cytokines in lung tissue and plasma concentrations after infecting tail-suspension mice,and induces more serious damages to the lung tissue,which suggests that inflammatory reactions can be increased in tail suspension mice infected by K.pneumoniae from spaceflight.

Establishment of a method for gene complementation in Vibrio parahaemolyticus / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a method for gene complementation in Vibrio parahaemolyticus using the plasmid pBAD33.</p><p><b>METHODS</b>The entire coding region of opaR or aphA was amplified by PCR and cloned into pBAD33. The recombinant plasmid was transformed into δopaR and δaphA (the opaR or aphA null mutant strain, respectively) separately to construct the complemented mutant strain C-δaphA and C-δopaR, respectively. RT-PCR was used to verify the transcription of opaR and aphA in the corresponding complemented mutant strains. Primer extension experiments were performed to determine the relative mRNA levels of mfpA (a gene previously characterized to be negatively regulated by AphA and positively by OpaR) in the wild-type strain, δopaR, δaphA, C-δaphA, and C-δopaR.</p><p><b>RESULTS</b>opaR and aphA were transcribed in the corresponding complemented mutant strains, and their mRNA levels were comparable to those detected in the wild-type strains.</p><p><b>CONCLUSION</b>A method has been established for gene complementation in Vibrio parahaemolyticus using the plasmid pBAD33.</p>

Influencing factors and preventive measures of polysomnography monitoring / 中国综合临床

Objective To observe the influencing factors of polysomnography (PSG) monitoring and to evaluate the efficacy of preventive measures.Methods We selected 205 patients with sleep apnea syndrome (SAS) who accepted PSG from May 2011 to April 2012 in our hospital as the intervention group.They were administered preventive measures,including psychological counseling,intensive grease dispelling of patient skin,arrangement of sensor and electrode.One hundred and fifty-two SAS patients who were administered PSG from May 2010 to April 2011 were selected as the control group.The monitoring successful rates between groups were compared and influencing factors were investigated.Results The monitoring successful rates of control group and the intervention group were 92.1％ and 97.1％ respectively; there was a statistically significant difference between the successful rates of the two groups (x2 =4.499,P ＜ 0.05).The main causes for unsuccessful monitoring were difficulty falling asleep,electrode distortion and high impedance of electrode.Conclusion PSG monitoring has a complex operating procedure and is time-consuming and effective preventive measures can improve the successful rate of PSG.

The differences in clinical characteristics between health care associated pneumonia and community acquired pneumonia in elderly patients / 中华老年医学杂志

Objective To reveal the differences in clinical characteristics between health care associated pneumonia (HCAP) and community acquired pneumonia (CAP) in elderly patients.Methods A total of 282 elderly patients were evaluated,including 69 patients with HCAP (25.5％) and 213 with CAP (75.5％).A retrospective observational study was conducted.The baseline characteristics,comorbidities,pathogen distribution,antibiotics,and clinical outcomes between HCAP and CAP patients were compared.Results The incidence of chronic obstructive pulmonary diseases and cerebrovascular diseases were higher in HCAP group (49 cases,71.0％; 36 cases,52.2％) than in CAP group (93 cases,43.7％; 57 cases,26.8％) (x2 =15.598,15.229,all P＜0.001).The infection of Pseudomonas aeruginosa (29 cases,51.8％),Staphylococcus aureus (19cases,34.0％) and Acinetobacter baumannii (18 cases,32.1％) in HCAP group were more than in CAP group [(26 cases,27.7％),(12 cases,2.8％),(8 cases,8.5％),(x2 =8.796,9.586,13.678,all P＜0.05)],respectively.While the infection of Streptococcus pneumoniae (38 cases,40.4％) in CAP group was much more than in HCAP group (4 cases,7.1％)(x2 =19.283,P＜0.001).Initial inappropriate antibiotics treatment failure was more frequent in HCAP group (24 cases,34.8％) than in CAP group (37 cases,17.3％)(x2=9.321,P＜0.05).The mortality was higher in HCAP group (19 cases,27.5％) than in CAP group (29 cases,13.6％)(x2 =7.151,P＜0.05).Conclusions HCAP should be distinguished from CAP in elderly,which is helpful to choose appropriate empirical anti-infective regimen and improve the effect of HCAP treatment.

Predictive equations of lung function for adults in north China urban areas / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish predictive equations of lung function for adults in urban areas in north China.</p><p><b>METHODS</b>A survey was conducted in 600 male and 600 female healthy adults in the urban areas in north China. Five flow-volume test parameters were measured including forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). Stepwise multiple regression was carried out to establish the predicative equations for the parameters for male and female adults separately. The predicted values from these equations and those from other commonly used equations (such as ECCS equation and Knudson equation) were compared with the actual measurements in pulmonary function tests.</p><p><b>RESULTS</b>Four flow-volume test parameters, namely FVC, FEV1, 25% forced expiratory flow (FEF25%), and FEF75%, showed obvious differences between the male and female adults, while FEV1/FVC was not correlated with gender. Multiple regression analysis showed that FVC, FEV1, FEF25% and FEF75% were positively correlated with height and negatively with age, and FEV1/FVC was negatively correlated with both height and age. The parameters were not affected by body weight. The predicted values from our equations were closer to the actual measurements than those calculated from other equations.</p><p><b>CONCLUSION</b>The equations we established are more appropriate than the generally used equations for predicting lung functions in adults in north China urban areas.</p>

Aminoglycosides Modifying Enzyme Genes and intⅠ gene in Stenotrophomonas maltoplilia / 中华医院感染学杂志

OBJECTIVE To study the aminoglycosides modifying enzyme genes and intⅠ gene in Stenotrophomonas maltophilia in Chinese Armed Police Forces General Hospital.METHODS The samples of 27 multi-resistant S.maltophilia were collected from inpatiens from Jan 2006 to Oct 2007 in this Hospital.The sensitivity of the isolates to 14 antibacterial agents was determined using a broth induction method.The aminoglycosides modifying enzyme genes and intⅠ 1 gene were detected by PCR.RESULTS The multi-drug resistance of S.maltophilia was a serious problem.In 27 strains of S.maltophilia,the positive ant(2″)-Ⅰ were in 5 strains(18.5%),aac(3)-Ⅱ in 3 strains(11.1%)and aac(6')-Ⅱ in 1 strain(3.7%).The positive intⅠ gene was found in 11 strains(29.6%).CONCLUSIONS Multi-resistant S.maltophilia resistant to aminoglycosides mainly due to the presence of aminoglycoside modifying enzymes ant(2″)-Ⅰ,aac(3)-Ⅱ and aac(6')-Ⅱ.The aminoglycoside modifying enzymes ant(3″)-Ⅰ and aac(6)-ⅠZ were not detected carrying IntⅠ would be the reason of S.maltophilia resistant to aminoglycosides.

Efficaly of Meropenem Against Infections:A Clinical Evaluation of 2732 Cases / 中华医院感染学杂志

OBJECTIVE To analyze the curative effect and bacterial clearance of meropenemagaint infections.METHODS To analyze 2732 cases with infection from more than 170 hospitals after meropenem.RESULTS The effectiveness ratio on various infections of blood,lungs treatmeot liver,gallbladder,and pancreas systems and on infections after transplantabions was 80.3%,87.1%,63.6% and 73.3%,respectively;the total clinical effectiveness ratio was 83.5%.The bacterial clearance ratio in various infections of blood,lungs liver,gallbladder,and pancreas systems and in infections after transplantations was 33.5%,66.2%,65.5% and 66.7%,respectively;the total bacterial clearance ratio was 52.7%.CONCLUSIONS Meropenem is effective against infection in clinical patients.The total clinical effectiveness ratio is 83.5%.The total bacterial clearance ratio is 52.7%.

Detection and Significance of Class Ⅱ Integrons in Clinically Isolated Strains of Stenotrophomonas maltophilia / 中华医院感染学杂志

OBJECTIVE To investigate the distribution and characterization of the classes Ⅰ,Ⅱ and Ⅲ integrons on Stenotrophomonas maltophilia and clarify their influence on the bacterial drug-resistance.METHODS A multi-PCR assay using specific primers of int1,int2 and int3 was constructed to screen classes Ⅰ,Ⅱ and Ⅲ integrons.RESULTS Class Ⅰ integron was detected in 13.4% of clinical isolates,3 isolates harbored among class Ⅱ integrons. There was not been reported in abroad.CONCLUSIONS Classes Ⅰ and Ⅱ integrons could play an important role in causing the antibiotic multidrug resistance.

Nosocomial Infections Caused by Stenotrophomonas maltophilia:Conditions and Associated Risk Factors / 中华医院感染学杂志

OBJECTIVE To investigate the conditions and associated risk factors of nosocomial infections caused by Stenotrophomonas maltophilia.METHODS Thirty isolates of S.maltophilia causing nosocomial infections were collected and identified with API 20NE test strips.Minimal inhibitory concentration(MIC) of 14 antimicrobial agents against 30 isolates was determined by broth microdilution method.Case-control study and multivariate Logistic regression analysis were used for statistics to verify risk factors of infections caused by S.maltophilia.RESULTS Thirty isolates of S.maltophilia were highly resistant to imipenem,meropenem,cefotaxime, aztreonam and amikacin,but showed certain susceptibility to cefoperazone/sulbactam,piperacillin/tazobactam,trimethoprim-sulfamethoxazole and ticarcillin/clavulanic acid(96.7%,76.7%,73.3% and 60.0%,respectively).The independent risk factors leading to infections of S.maltophilia were mechanical ventilation(OR=7.629) and over 60 days of length of stay(OR=4.466).CONCLUSIONS S.maltophilia shows multiresistance to commonly used antimicrobial agents.The mechanical ventilation and over 60 days of length of stay are the independant risk factors for nosocomial infections caused by S.maltophilia.

Procalcitonin in Diagnosing and Prognosis Predicting of Ventilator-associated pneumonia and Its Clinical Significance / 中华医院感染学杂志

1.2 ng/ml on the third day as a threshold,the sensitivity,and specificity in predicting the prognosis of VAP were 81.0%,and 87.5%,respectively. CONCLUSIONS The results suggested that serum PCT be important for the diagnosis of VAP.PCT concentration over 1.2 ng/ml as a threshold is more sensitive and specific to distinguishing different outcomes.And the sensitivity and specificity of PCT are better than that of IL-6,IL-8.

Change of testosterone and CD4+/CD8+ T cell in long-term mechanical ventilation patients with chronic obstructive pulmonary disease / 中国康复理论与实践

@#ObjectiveTo investigate the change of the level of testosterone and CD4+/CD8+ T cell in long-term mechanical ventilation patients with chronic obstructive pulmonary disease (COPD) and their correlation.MethodsThe level of testosterone, count of CD4+ and CD8+ T cell were measured in 42 COPD patients accepted long-term mechanical ventilation and other 34 stable COPD patients. The ratio of CD4+/CD8+ was calculated.The correlation between testosterone and CD4+/CD8+ was analyzed.ResultsCompared with the stabel COPD, there were significantly differences in the level of testosterone and the ratio of CD4+/CD8+ in long-term mechanical ventilation COPD group(P<0.05), but there was not relationship between them.ConclusionThe level of testosterone and the ratio of CD4+/CD8+ were significantly decreased in COPD patients with long-term mechanical ventilation. There is no correlation between the level of testosterone and the ratio of CD4+/CD8+.

The cytotoxicity of histone deacetylase inhibitor plus paclitaxel to lung cancer cells / 解放军医学杂志

Objective To evaluate the cytotoxicity of trichostatin A (TSA),a histone deacetylase inhibitor,plus paclitaxel to H1299 strain lung cancer cells. Methods H1299 cells were exposed to TSA and/or paclitaxel in different concentrations in different ways. The proliferation rates were determined by MTT assay,the 50% inhibition concentration (IC50) of paclitaxel was calculated and the growth curve was plotted. The H1299 cells were then divided into 4 groups:control group (cells were normally cultivated for 36h),TAX group (cells were treated with 10nmol/L of paclitaxel for 24h),TSA group (cells were treated with 300nmol/L of TSA for 24h) and TF group (cells were exposed to TAX for 24h after being treated with TSA). Cell cycle and apoptosis were determined by flow cytometry. The morphological changes in nuclei as stained with Hoechst 33342 were observed by fluorescence microscopy. The protein expression levels of p21 and cleaved poly-ADP ribose polymerase (PARP) were determined by Western blotting. Results TSA significantly enhanced the inhibition of paclitaxel in lung cancer cell lines H1299. When combined with TSA,the IC50 of paclitaxel decreased significantly from 110.6?38.7nmol/L to 63.7?11.8nmol/L in H1299 cells (P0.05). Conclusion The HDAC inhibitor TSA,combined with TAX,may enhance the cytotoxicity of paclitaxel to,and promote the death of,lung cancer cell line H1299,which may not be related to apoptosis.

Effects of ligustrazine on the calcineurin-? expression in lung tissue of rats under simulated weightlessness condition / 解放军医学杂志

Objective To study the dynamic changes in calcineurin-? expression in lung tissue of rats under simulated weightlessness condition,and the influence of ligustrazine(tetramethylpyrazine) on the changes in its expression.Methods The rat model of simulated weightlessness condition was reproduced by suspending the rat by tail in-30?.Thirty healthy Wistar rats were randomly divided into 3 groups(10 each): control group,suspended group(rat was suspended by tail for 7 days) and ligustrazine group(rat was suspended by tail and ligustrazine was given for 7days).In the ligustrazine group,the ligustrazine was gavaged in a dose of 1.5mg/kg(once a day).The expression of calcineurin-? in lung tissue was determined by immunohisochemistry and Western blotting.Results It was revealed by immunohisochemistry and Western blotting that the level of expression of calcineurin-? in lung tissue of the animals in suspended group was significantly higher that in control group and ligustrazine group(P0.05).Conclusion The level of expression of calcineurin-? in rat lung tissue may be increased obviously under the simulated microgravity condition,while ligustrazine treatment may down-regulate the calcineurin-? expression.

Effects of simulated gravity loss on nuclear factor kappa-B expression in rats′ pulmonary tissue / 解放军医学杂志

Objective To study the effects of simulated gravity loss on nuclear factor Kappa-B expression in rats′ pulmonary tissue, and to investigate the mechanism of changes in NF-?B during simulated loss of gravity. Methods Tail-suspension(TS) was used as the method to simulate the physiological effects of weightlessness. 40 Wistar male rats Wistar rats were randomly divided into 4 groups: control for 7 days (7d CON), 21d CON, TS for 7d (TS7d) and TS21d. The dynamic express of nuclear factor Kappa-B in lung tissue was respectively assessed using the immunohisochemical technique. Results Compared with control group, the expression level of NF-?B in the lung tissue of tail-suspension 7d rats was elevated significantly (P

Effects of simulated weightlessness on eNOS expression in pulmonary artery in rat / 解放军医学杂志

Objective To study the effects of simulated weightlessness on eNOS expression in the pulmonary artery in rat, and to investigate the mechanism of changed reactivity of pulmonary artery during simulated weightlessness. Methods The experiments were conducted in 16 male Wistar rats, and they were divided into 2 groups: suspension group and control group, 8 rats for each. Tail-suspension (-30?) was carried out for 14d to simulate weightlessness. eNOS protein expression and NO content in pulmonary artery were determined using Western blot analysis and nitrate enzyme-reduction method, respectively. Results Compared with control group, eNOS expression in the rat pulmonary artery increased significantly during simulated weigtlessness. The relative optical density as a result of scanning was 247?2.60, and that of the control was 141?1.72. There were significant differences between the two groups (P

Effects of dexamethasone on iNOS in pulmonary tissues of rats during simulated weightlessness / 解放军医学杂志

Objective To investigate the effects of dexamethasone on inducible nitric oxide synthase (iNOS) in pulmonary tissues of tail-suspended rats simulating weightlessness. Methods Twenty Sprague-Dawley male rats were randomly divided into 2 groups: tail-suspended for 7 days (n=10) without treatment and dexamethasone treatment group (n=10). Tail-suspension was used to simulate weightlessness. The expression of iNOS in the pulmonary tissue was examined by Western blot and immunohistochemistry. Results The results showed that the level of iNOS in the pulmonary tissue of treatment group was decreased significantly(P

Effects of dexamethasone on cell apoptosis in pulmonary tissues in rats after tail-suspension simulating weightlessness / 解放军医学杂志

Objective To investigate the effects of dexamethasone on prevention of apoptosis in pulmonary tissues of rats after simulated weightlessness. Methods Tail suspension was used to simulate weightlessness. Thirty Sprague-Dawley male rats were divided randomly into 3 groups: control group, tail suspension for 7 days group, and dexamethasone treatment after suspension group. TUNEL technique was used to detect cell apoptosis in pulmonary tissues. Results The rate of apoptotic cells in the lung of rats suspended for 7 day was higher than that of control group(P

STUDY ON CELL APOPTOSIS GENES IN PULMONARY TISSUE OF TAIL-SUSPENDED RATS DURING SIMULATED WEIGHTLESSNESS / 解放军医学杂志

To investigate the changes of cell apoptosis genes in pulmonary tissue of tail suspended rats during simulated weightlessness, 40 Spragno Dawley male rats were divided into 4 groups: suspended for 7d,control of 7d, suspended for 21d, and control of 21d.Tail suspension(-30?) was used as weightlessness simulation.The condition of bcl 2/bax in pulmonary tissues was detected by in situ hybridization. The results showed that the level of bcl 2 mRNA in pulmonary tissue of 7d tail suspended rats decreased significantly( P 0 05). The results also showed that the level of bax mRNA in pulmonary tissue of 7d tail suspended rats increased significantly( P 0 05).It can be concluded that there are certain changes of cell apoptosis genes in pulmonary tissue of 7d tail suspended rats during simulated weightlessness.

STUDY ON EXPRESSION OF VEGF mRNA IN PULMONARY TISSUES OF TAIL-SUSPENDED RATS DURING SIMULATED WEIGHTLESSNESS / 解放军医学杂志

To investigate the changes of vascular endothelial growth factor mRNA (VEGFmRNA) in pulmonary tissues of tail suspended rats during simulated weightlessness,the experiments were conducted on 40 Spragno Dawley male rats,divided into 4 groups:suspended for 7d,control of 7d and suspended for 21d,control of 21d.Tail suspension(-30?) was used as weightlessness simulation.The condition of VEGFmRNA in pulmonary tissues was examined by hybridization in situ. The results showed that the level of VEGFmRNA in pulmonary tissues of 7d tail suspended rats increased significantly( P