Objective To compare the Legionella contaminative status of the cooling water system with freezing water system in central air conditioning system. Methods Legionella was tested in water and samples of all components from the cooling tower, condenser, swelling water box and evaporator of central air conditioning among 26 public places. Results The total detected rate of Legionella was 64.0% among 100 samples from two kinds of water system, 71 strains of Pneumophila legionella were separated. The detected rates were 75.0% and 52.1% in the cooling water systems and freezing water systems respectively. The amount of Legionella was more than 100 per milliliter in the cooling water systems. The detection rate of cooling tower water and swelling water box water was 100% in the air conditioning system run for over 10 years and 5-10 years. Concordance rate of consequence was 50.0% in cooling tower water and condenser water of the cooling water systems, the rate was 55.0% in swelling water box water and evaporator water of the freezing water systems. Conclusion This study suggested that more attention should be paid to the contaminative status of Legionella in freezing water system of central air conditioning system. Cooling tower and swelling water box should be the key parts in cleaning and disinfection of air conditioning system.

BACKGROUND:Superparamagnetic iron oxide nanoparticles (Fe3O4 NPs) have been widely used in MRI. It is vital to prepare the superparamagnetic MRI contrast agent with high stability, biocompatibility and tumor targeting in order to prevent the aggregation of Fe 3 O 4 NPs and realize the high-precision diagnose of tumor. OBJECTIVE:To prepare the amphiphilic superparamagnetic composite particles with tumor targeting mediated by folate receptor. METHODS:The stable amphiphilic superparamagnetic composite particles with tumor targeting function were prepared by coating the Fe3O4 NPs with a Pluronic F127-folic acid conjugate, which was synthesized via an esterification reaction between the carboxyl group of the tumor targeting molecule, folic acid and the hydroxyl group of an amphiphilic triblock copolymer, Pluronic F127. The resultant Pluronic F127-folic acid-Fe3O4 composite particles were characterized by transmission electron microscopy, Fourier transform infrared-spectra, UV-vis absorption spectra, thermal gravimetric analysis, vibrating sample magnetometer and T2-weighted imaging. WST assay was used to characterize their cytotoxicity preliminarily. RESULTS AND CONCLUSION:The Pluronic F127-folic acid conjugates were prepared via esterification reaction. Then Fe 3 O 4 NPs were wrapped with Pluronic F127-folic acid to result in the superparamagnetic composite particles with wel dispersion and biocompatibility. The size of most superparamagnetic composite particles was less than 200 nm and the size of Fe 3 O 4 core was 10-20 nm from the observation of transmission electron microscopy. The results from the Fourier transform infrared-spectra and UV-vis absorption spectroscop confirmed that folic acid molecules were modified on the surface of the superparamagnetic composite particles successful y. The mass ratio of Pluronic F127-folic acid conjugate was determined by thermal gravimetric analysis as 27.2 wt%in the resultant Pluronic F127-folic acid-Fe 3 O 4 composite particles. The saturated magnetic intensity of the superparamagnetic composite particles was 47.35 emu/g by vibrating sample magnetometer and the relaxation rate was 0.025×106 mol/s from MRI. The WST assay showed the negligible cellcytotoxicity of Pluronic F127-folic acid-Fe3O4. The superparamagnetic composite particles have potential application as the MRI contrast agents with tumor targeting, and the Pluronic F127-folic acid-Fe 3 O 4 composite particles is expected to be used as a MRI contrast agent for tumor targeting.

Objectives To investigate etiology, clinical characteristics and outcome in children with epilepsia partialis continua (EPC). Methods Sixty-three pediatric patients with EPC were retrospectively analysed. The patients aged (5.53±3.65) years old, with brain CT scans or MRIs after diagnosis, basic laboratory tests, cerebrospinal lfuid analysis and electroencephalog-raphy. The average follow-up time was (22.19±21.19) months (6-72 months). Results The median duration of EPC was 11 days (1-180 days). The causes of EPC were inlfammatory and immune-mediation (36 cases, 57.14%, Rasmussen’s encephalitis included), metabolic disorders (8 cases, 12.70%), brain structure abnormalities (5 cases, 7.94%), vascular malformation (5 cases, 7.94%), dual causes (3 cases, 4.76%), post brain surgery (2 cases, 3.17%) and cryptogenic pathogenesis (4 cases, 6.35%). Neurological dysfunc-tions were observed in 44 cases (69.84%). Age, routine cerebrospinal lfuid abnormalities, the presence of inlfammation and im-mune mediated, EPC long duration, involving the right upper extremity were the risk factors of poor prognosis. Conclusions The most common causes of childhood EPC are inlfammation and immune-mediated central nervous system diseases. Patients with early age of onset, a great tendency of longer duration of EPC and cerebrospinal lfuid abnormalities, involving the right upper ex-tremity have a poor prognosis.

OBJECTIVE: Previous opinions consider the secondary diffuse osteoporosis as the very cause of vertebral fractures in patients with ankylosing spondylitis (AS). However, recent studies on bone mineral density (BMD) and vertebral fractures in AS patients reveal that there is no relation between the two. This article aims at investigating the association of lumbar vertebral fractures with clinical, laboratory, and imaging indexes in AS patients.METHODS: A contrast observation was performed between 65 AS patients and 62 healthy physical examinees, whose lumbar vertebral plain radiographs were taken for checking vertebral fractures. Disease activity evaluation indexes included C-reactive protein, erythrocyte sedimentation rate, finger-to-ground distance, Schobar's index score, Bath AS radiology index (BASRI) and syndesmophyte score. Dual energy X-ray absorptiometry technique was used to measure BMD levels of lumbar vertebras and femurs.RESULTS: Out of the total 65 AS patients, 10 ones (15.4%) had lumbar vertebral fractures, with 4 ones with wedge deformities and the other 6 ones with biconcave deformities. BMD levels of Lumbar vertebras and femurs in AS patients were significantly lower than those in controls (P < 0.01). There were significant differences in Schober's index scores, finger-to-ground distance scores, Bath scores, syndesmophyta scores and intertrochanter BMD values between AS patients with and without vertebral fractures (P < 0.01 ). Multiple logistic regression analyses revealed that intertrochanter BMD values were independently associated with lumbar vertebral fractures in AS patients (P =0.043).CONCLUSION: There is a correlation between low femoral BMD levels and the risk of lumbar vertebral fractures in patients with AS, especially at the intertrochanter area.

Objective To find out the proper concentration of ZnSO4?7H2O as foliar fertilizer used for Pinellia ternata, and to provide reference for high yield of P.ternate,effects of zinc on the carbon and nitrogen metabolism in leaves of P.ternata and the yield were studied.Methods Seedlings of P.ternata were employed as the experiment material.At the stage of full seedling,ZnSO4?7H2O of different concentration was sprayed on the leaves,the indexes of carbon and nitrogen metabolism were determined on the day 10,the weight of tubers and bulbils were measured at the sprout tumble stage.Results The yield of P.ternata has an exceedingly significant positive correlation with the contents of soluble sucrose and starch in the leaves,a significant positive correlation with the content of photosynthetic pigment and the aldolase activity,and a negative correlation with the amylase activity.In addition,the yield shows both an exceedingly significant positive correlation whith the nitrate reductase activity and a significant positive correlation with the content of protein.At the stage of full seedling,zinc sprayed on leaves can increase the content of photosynthetic pigment and improve the capability of photosynthesis.Meanwhile,spraying zinc can also promote the accumulation of soluble sucrose and starch in the leaves because of its stimulation on aldolase and inhibition on amylase.Besides,spraying zinc on leaves could improve the activity of nitrate reductase and the content of protein,and finally increase the yield of P.ternata.Conclusion The concentration of 600 mg/L is the best for ZnSO4?7H2O used as foliar fertilizer for P.ternate at the stage of full seedling.

Objective To discuss the intervention effects and mechanisms for Rapamycin on renal interstitial fibrosis in rats.Methods A total of 72 Wistar male rats were randomly divided into 3 groups,normal group(n =24) ,model group(n =24), treatment group (n =24).The model group and treatment group received adenine 200 mg/kg daily,and the treatment group was also given Rapamycin 5 mg/(kg·d) at the 8th day,the normal group was just given the same amount of normal saline for 6 weeks.In the end of the 2nd,4th and 6th week,8 rats in each group were sacrificed respectively.The expression of hepatocyte growth factor(HGF), transforming growth factor-β (TGF-β) and neutrophils gelatinases related apolipoprotein (NGAL) in each group were observed.The software of image analysis system was used for semi-quantitative analysis.Results HE and Masson staining results showed that the renal tubular were progressive swelling, and changed with interstitial fibrosis,atrophy and even necrosis in model group from 2 weeks to 6 weeks.The pathological changes of kidney were more ease in the treatment group compared with those in model group.Immunohistochemical staining results showed that HGF expression levels of renal interstitial tissue in model group and treatment group at the 2nd week were significantly higher than those of normal group(P ＜0.05), and were significantly decreased at the 4th week and 6th week (P ＜ 0.05);HGF expression levels of renal interstitial tissue in treatment group were significantly higher than those in model group (P ＜ 0.05).NGAL expression levels of renal interstitial tissue in model group and treatment group at the 2nd week were significantly higher than those in normal group(P ＜0.05) ,and were significantly decreased at the 4th week and 6th week(P ＜ 0.05);NGAL expression levels of renal interstitial tissue in treatment group were significantly higher than those in model group (P ＜ 0.05).TGF-β expression levels of renal interstitial tissue in model group and treatment group at the 2nd,4th,and 6th week were significantly higher than those in normal group (P ＜0.05) ,while TGF-β expression levels of renal interstitial tissue in treatment group were significantly lower than those in model group (P ＜ 0.05).Conclusion Rapamycin could improve the rat kidney tissue pathology, relieve renal tubular expansion, and slow progression of renal interstitial fibrosis, and has certain protective effect to the kidney.

BACKGROUND:It is vital to choose the appropriate carrier with low toxicity and high gene transfection efficiency in gene therapy, which is harmless to human body and environment. OBJECTIVE: To prepare superparamagnetic Fe3O4/SiO2-polyethyleneimine (PEI) composite particles. METHODS: Fe3O4 nanoparticles were prepared via an emulsion solvent evaporation method and superparamagnetic Fe3O4/SiO2 core shel microspheres were prepared successfuly subsequently via a modified stober method. The microspheres were further modified with PEI to obtain superparamagnetic Fe3O4/SiO2-PEI composite particles. The structures and properties of resultant composite particles microspheres were characterized by transmission electron microscopy, zeta potential and vibrating sample magnetometer. Superparamagnetic Fe3O4/SiO2-PEI composite particles were mixed with plasmid DNA at different mass ratios (29∶1, 39∶1, 49∶1, 59∶1, 68∶1, 78∶1, 88∶1). Thein vitro gene transfection ability was evaluated by Hela cels with the transfection of plasmid DNA encoded with green fluorescent protein and the transfection efficiency was determined by confocal fluorescence microscopy. RESULTS AND CONCLUSION: We successfuly synthesized the Fe3O4/SiO2-PEI composite particles with good dispersibility and even size distribution (about 100 nm). The surface charge was 21.07 mV, and the saturation magnetization was 28.05 emu/g that meant superparamagnetism. When the mass ratio was 59∶1, al the plasmid DNA was adherent to the Fe3O4/SiO2-PEI composite particles; when the mass ratio was > 59∶1, there were excessive Fe3O4/SiO2-PEI composite particles. Therefore, the mass ratio of 59:1 could lead to a better outcome for HeLa celltransfection. These results indicate that the Fe3O4/SiO2-PEI composite particles can dramaticaly improve the transfection efficiency of plasmid DNA compared with PEI.

Objective To compare the fusion effect between lumbar posterolateral fusion (PLF) and posterior lumbar interbody fusion (PLIF) in elderly patients with lumbar spinal stenosis.Methods Data of 313 patients undergoing PLF or PLIF for treatment lumbar degenerative disease in Department of Orthopedics,Beijing Hospital of China Ministry of Health during January 1996 to December 2011 were retrospectively analyzed.Patients were divided into PLF group (n=116 cases) and PLIF group (n=197 cases).Data of fusion rate,operative time,operative blood-loss and complications were analyzed statistically.Results The fusion rate was 84.5％ in PLF group and 98％ in PLIF group.The average operative time was 247.8 min (120-480 min) and 240.6 min (90-600 min) in PLF and PLIF groups respectively.The blood-loss was 1142.9 ml (200 4500 ml) and 927.0 ml (200-2800 ml) in PLF and PLIF groups respectively.Postoperative complications were found in 38 cases in PLF group and in 36 cases in PLIF group.There were significant differences in fusion rate,operative time,operative blood loss,complications between the two groups (all P＜0.05).Conclusions PLIF has better effects on fusion rate and fusion grade than PLF.

Objective To explore one mechanism of therapeutic action of electroacupuncture on Alzheimer’s disease (AD), that is, improving the way to eliminate cerebral microvascular Ab by investigating the effect of electroacupuncture on hippocampal microvascular Ab deposition and learning and memory abilities in APP/PSI double transgenic mice. Method Twenty-four 7-month-old male APP/PSI double transgenic mice were randomized into model and electroacupuncture groups, 12 mice each. Same sex transgene-negative littermate mice (12 mice) constituted a blank control group. The electroacupuncture group received electric acupuncture at points Baihui (GV20) and Yongquan (KI1), 15 min once every other day, for a total of six weeks. After treatment, mouse learning and memory abilities were tested using the Morris water maze. The expressions of Ab 1-40 and Ab 1-42 in the hippocampal microvascular wall and senile plaque were determined by immunohistochemical method. Hippocampal microvascular Ab-positive expression was semi-quantitatively analyzed using the Imagine Pro Plus software. Result The Morris water maze test showed that escape latency lengthened (P<0.05), and the number of crossing platform and swimming time in the platform quadrant decreased (P<0.05) in the model group compared with the blank control group. Escape latency shortened (P<0.05), and the number of crossing platform and swimming time in the platform quadrant increased (P<0.05) in the electroacupuncture group compared with the model group. The immunohistochemical results showed that hippocampal microvascular Ab 1-42 and Ab 1-40 integral optical densities were higher in the model group than in the blank control group (P<0.05) and senile plaques appeared in the hippocampus. Hippocampal microvascular Ab 1-42 and Ab 1-40 integral optical densities were lower in the in the electroacupuncture group than in the model group (P<0.05). Conclusion Electroacupuncture reduces mouse learning and memory impairments and hippocampal microvascular Ab deposition. Its mechanism may be that electroacupuncture improves the way of eliminating cerebral microvascular Ab to decrease cerebral Ab deposition.

Oral medicine and deep brain stimulation are two main treatments for Parkinson′s disease (PD). But their long-term efficacies are decreasing, which limit the choice of patients in advanced stage. As a special way of sensory intervention, rhythmic cueing can improve gait parameters, reduce freezing of gait severity and improve gait-related mobility by activating the motor pathway directly, repairing internal clock, promoting internal dopamine release and improving cognitive function to maintain gait stability. Rhythmic auditory and visual cueing has a potential in PD treatment.