Catechol-type siderophores secreted by a strain of soil bacteria in three different medium were assayed by two high-resolution TLC.The results showed different medium had a significant effect on the secretion of catechol-type siderophores,and in three different medium strain S1 produced different catechol-type siderophores.The effect of Al~(3+) on Catechol-type siderophores by S1 were also assayed.The results showed Al~(3+)had a significant stimulation on the secretion of catechol-type siderophores.Moreover,Al~(3+)could to some extent counteract the repression of Fe~(2+)on siderophores production.In KMB medium four catechol-type siderophores were identified and all ones except for 2,3-dihydroxybenzoic acid(2,3-DHBA) had high affinity for Al~(3+).

Background Research showed that transforming growth factor-β2 (TGF-β2) promotes scar formation.But its mechanism in scarring after glaucoma filtration surgery is worthy of studying.Objective This study was to investigate the effect of TGF-β2 on myofibroblast transition of human Tenon fibroblasts (HTFs) and scarring after glaucoma filtration surgery.Methods Tenon capsular tissue was obtained from 3 patients with strabismus during the surgery and was incubated in DMEM with 10％ fetal bovine serum (FBS).The cells were collected and passaged in the free-serum medium for 24 hours,and then 1,2,5,10,20 μg/L TGF-β2 was added into the medium respectively,to induce the transformation of HTFs,and 2 μg/L or 5 μg/L TGF-β2 was used to treat the HTFs for 6,24,48 and 72 hours.The control group was not treated with TGF-β2.The expressions of α-smooth muscle actin (α-SMA) and phosphorylation of the signaling proteins (pSmad2) in HTFs were detected by Western blot assay.The expressions of α-SMA and F-actin were located by cell immunofluorescine technique under the confocal immunofluorescence microscopy.Cell contractility was determined by collagen gel contraction assays.This study was approved by Ethic Committee of Institute of Surgery Research of Daping Hospital,and informed consent was obtained from each patient or custodian initial of the study.Results The expression of α-SMA protein in the HTFs was increased significantly after the treatment of TGF-β2 in comparison with the control group and reached a peak at 24-48 hours.The α-SMA expression was gradually weakened in the 10 μg/L TGF-β2 groups.Little of α-SMA and F-actin were expressed in the control group.However,strong staining for α-SMA and F-actin were observed in the 1,2 and 5 μg/L TGF-β2 groups and then the staining weakened at the concentration of 10 μg/L.In addition,pSmad2 showed a stronger expression in the 2 μg/L TGF-β2 group than that in the PBS group and FBS group,with the strongest expression in 30 minutes through 2 hours.The untreated gel contracted (78.00±3.13)％ from its initial size,and contraction in the 1,2,5,10 μg/L TGF-β2 group were (63.88±1.78)％,(20.69±0.65)％,(19.49-±0.54)％,(16.24±0.84) ％,respectively,TGF-β2 increased HTFs contraction significantly (Fgroup =859.400,P =0.000).Conclusions TGF-β2 can induce transdifferentiation of Tenon fibroblast into myofibroblast and increase cell contractility,with a concentration-dependent and time-dependent pattern to an extent.It may be the mechanism of scar formation after glaucoma filter surgery.

Currently, monitoring system of awareness of the depth of anesthesia has been more and more widely used in clinical practices. The intelligent evaluation algorithm is the key technology of this type of equipment. On the basis of studies about changes of electroencephalography (EEG) features during anesthesia, a discussion about how to select reasonable EEG parameters and classification algorithm to monitor the depth of anesthesia has taken place. A scheme which combines time domain analysis, frequency domain analysis and the variability of EEG and decision tree as classifier and least squares to compute Depth of anesthesia Index (DOAI) is proposed in this paper. Using the EEG of 40 patients who underwent general anesthesia with propofol, and the classification and the score of the EEG annotated by anesthesiologist, we verified this scheme with experiments. Classification and scoring was based on a combination of modified observer assessment of alertness/sedation (MOAA/S), and the changes of EEG parameters of patients during anesthesia. Then we used the BIS index to testify the validation of the DOAI. Results showed that Pearson's correlation coefficient between the DOAI and the BIS over the test set was 0.89. It is demonstrated that the method is feasible and has good accuracy.
Algorithms ; Anesthesia, General ; Decision Trees ; Electroencephalography ; Entropy ; Humans ; Intraoperative Awareness ; Monitoring, Physiologic ; Propofol

Adolescent ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Hepatitis B ; epidemiology ; immunology ; prevention & control ; Humans ; Infant ; Infant, Newborn ; Male

OBJECTIVE:To describe the characteristics of existing numerical methods,conclude current mainstream bio-electromagnetism simulation softwares,focusing on their different directions,and explore the developing trends of bio-electromagnetism computing platform.DATA SOURCES:A computer-based online search of Wanfang,Sciencadirect (Elsevier),and IEEE database was performed for articles published between 1999 and 2009 with the key words "bio-electromagnetism,simulation,numerical simulation,FDTD* in Chinese and English.A total of 83 articles were collected,including 28 Chinese and 55 English.Four software introduction and user manuals were manually retrieved.DATA SELECTION:Articles were screened by reading the title and abstract,and the latest relevant research literatures in the same kinds of simulation methods were included.MAIN OUTCOME MEASURES:A total of 25 articles with no related content,and 27 repetitive and outdated studies were excluded.Finally,31 Chinese and English articles were included for further analysis,involving 8 reviews and comments and 23 original articles.RESULTS:Common electromagnetic field numerical calculations include time domain finite difference method,moment method,and finite element method.Currently,the bio-electromagnetism simulation softwares used in electromagnetic radiation on organism include SEMCAD-X,FEKO,XFDTD,HFSS and GEMS.CONCLUSION:Future bio-electromagnetic computing platform is expected to integrate a variety of numerical methods to meet the research needs of a variety of simulation objects.In addition,interface facilitation of simulation and flowsheet of modeling will be the focus of future improvements.

Objective To evaluate a new system,Vitek 2 Compact,for identification of bacteria and yeasts.Methods 185 clinical isolates of Peking Union Medical College Hospital,including 69 gram- positive strains,66 gram-negative strains and 50 yeasts,and 50 reference strains in our laboratory,including 25 gram-positive and gram-negative strains respectively,were studied.All the strains were identified by Vitek 2 Compact with GP,GN or YST identification cards.The API method was used as the reference method.Results Among the 93 gram-positive strains,85 strains(91.40%)were correctly identified, including 5 low discrimination identified strains,and 8 strains(8.60%)were correctly identified to the genus level,but misidentified to the species level.About 90% of gram-positive strains were identified within 7 h.Out of 91 gram-negative strains,90 strains(98.90%)were correctly identified,with 5 low discrimination identified strains,only 1 strain(1.1%)was correctly identified to the genus level,but misidentified to the species level.Above 90% of Enterobacteriaceae were identified within 5 h,and over 90% of nonfermenting bacteria were identified within 10 h.In the 50 strains of yeasts,46 strains(92%) were correctly identified,including 8 low discrimination identified strains,and 4 strains(8%)were correctly identified to the genus level,but misidentified to the species level.In all the yeasts,45 strains (90%)were identified in 18.25 h,and another 5 strains(10%)were identified in 18.50 h.Conclusions As Vitek 2 Compact system can give us reliable identification results of clinically relevant bacteria and yeasts,together with its significant reduction of handling time,it will definitely become a powerful tool in clinical microbiology laboratory.

Objective To evaluate a new system,Vitek 2 Compact,for antimicrobial susceptibility testing(AST)of gram-negative and gram-positive bacteria.Methods Eighty-nine clinical isolates of Peking Union Medical College Hospital,including 48 gram-negative strains and 41 gram-positive strains,and 66 reference strains kept in our laboratory,including 41 gram-negative strains and 25 gram-positive strains, were studied.The antimicrobial susceptibility of these strains were tested by Vitek 2 Compact with AST- GN09(for gram-negative bacteria),AST-P536(for Staphylococci),AST-P534(for Enterococci and S.agalactiae),and AST-P533(for S.pneumoniae)susceptibility cards.The Etest was used as the reference method for comparision.Thirty-two ESBL-producing strains assessed with the confirmatory tests for ESBLs of CLSI(16 strains of them had been confirmed by PCR amplified and sequencing)were detected for ESBLs by Vitek 2 Compact.Results According to the breakpoints of Clinical and Laboratory Standards Institute (CLSI),for the 1 626 microorganism-antibiotic combinations,Vitek 2 Compact gave 90.83% strains with category agreement(CA),4.91% strains with very major errors(VME),2.09% strains with major errors (ME),6.40% minor errors(MIE).The AST for more than 90% of Enterobacteriaceae,nonfermenting bacteria,micrococci and streptococci were completed within 11h,13h,11h and 12h,respectively.The ESBLs tests for thirty-two strains by V-itek 2 Compact are all positive.Conclusions Vitek 2 Compact system can give rapid,reliable and reproducible result with high sensitivity and specificity in assessment of antimicrobial susceptibility testing for clinically relevant gram-negative and gram-positive bacteria,and would become a powerful tool in clinical microbiology laboratory.

Background Our previous study demonstrated that the aptamer S58 specifically targeted transforming growth factor-β receptor Ⅱ (TβRⅡ) and inhibited the transdifferentiation of human Tenon capsule fibroblasts (HTFs) mediated by transforming growth factor-β (TGF-β).Chitosan-nanoparticles (CS-NP) are good drug carriers,but the efficacy and safety of CS-NP/aptamer complexes deserve attention.Objective The aim of this study was to synthesize a novel CS-NP/aptamer complex called CS (S58)-NP and investigate its properties and applicability.Methods Human Tenon capsule tissue was obtained from patients during strabismus surgery,and HTFs were cultured and passaged using the explant culture method.The fourth to tenth generations of cells were used in the experiment.Different concentrations of CS-NP were used to prepare the CS(S58)-NP by the ionic cross-linking method with a surface charge rate (N/P) for S58 of 10,20,30 or 40.The particle size and Zeta potential were measured by the Zeta analyzer.The shape and distribution of CS (S58)-NP particles were examined under the scanning electron microscope.The binding of CS-NP with S58 and resistance of CS (S58)-NP to DNase Ⅰ were examined by agarose gel eletrophoresis.The release rate of S58 from CS (S58)-NP in PBS was quantitatively analyzed by a ultraviolet spectrophotometer.The cytotoxicity of CS(S58)-NP to HTFs was evaluated by detecting the production of lactate dehydrogenase (LDH).Results The Zeta analyzer showed that the particle size of CS (S58)-NP was 130-270 nm and its electric potential ranged from + 16 to +28 mV.The CS (S58)-NP particles appeared spherical with an even distribution under the scanning electron microscope.The mean encapsulation efficiency of CS(S58)-NP was 88.9％,89.3％,91.7％ or 90.5％,respectively,when the N/P was 10,20,30 or 40.After being encapsuled by CS-NP,S58 could resist the degradation from DNase I.Its total releasing level in PBS increased with the lapse of time,with a maximum releasing speed at 24 to 36 hours.The total releasing level reached 100％ at 96 hours.With increaseing concentrations of CS(S58)-NP,the relative releasing level of LDH in HTFs suspension gradually elevated with a significant difference among the groups (F =588.018,P =0.000),with the highest released LDH level at 50 nmol/L of CS(S58)-NP (12.853％ ±0.375％).Conclusions CS-NP provides a protective and slow-releasing effect on the S58 aptamer.CS (S58)-NP shows a good biocompatibility with HTFs with a low cytotoxicity at a concentration of ＜50 nmol/L.CS(S58)-NP could be used to inhibit TGF-β induced transdifferentiation of HTFs in the future.

The clinical analgesic effect of electro-acupuncture (EA) stimulation (EAS) on breakthrough pain induced by remifentanil in patients undergoing radical thoracic esophagectomy, and the mechanisms were assessed. Sixty patients (ASAIII) scheduled for elective radical esophagectomy were randomized into three groups: group A (control) receiving a general anesthesia only; group B (sham) given EA needles at PC4 (Ximen) and PC6 (Neiguan) but no stimulation; and group C (EAS) electrically given EAS of the ipsilateral PC4 and PC6 throughout the surgery. The EAS consisting of a disperse-dense wave with a low frequency of 2 Hz and a high frequency of 20 Hz, was performed 30 min prior to induction of general anesthesia and continued through the surgery. At the emergence, sufentanil infusion was given for postoperative analgesia with loading dose of 7.5 μg, followed by a continuous infusion of 2.25 μg/h. The patient self-administration of sufentanil was 0.75 μg with a lockout of 15 min as needed. Additional breakthrough pain was treated with dezocine (5 mg) intravenously at the patient's request. Blood samples were collected before (T1), 2 h (T2), 24 h (T3), and 48 h (T4) after operation to measure the plasma β-EP, PGE2, and 5-HT. The operative time, the total dose of sufentanil and the dose of self-administration, and the rescue doses of dezocine were recorded. Visual Analogue Scale (VAS) scores at 2, 12, 24 and 48 h postoperatively and the incidence of apnea and severe hypotension were recorded. The results showed that the gender, age, weight, operative time and remifentanil consumption were comparable among 3 groups. Patients in EAS group had the lowest VAS scores postoperatively among the three groups (P<0.05). The total dose of sufentanil was 115±6.0 μg in EAS group, significantly lower than that in control (134.3±5.9 μg) and sham (133.5±7.0 μg) groups. Similarly, the rescue dose of dezocine was the least in EAS group (P<0.05) among the three groups. Plasma β-EP levels in EAS group at T3 (176.90±45.73) and T4 (162.96±35.00 pg/mL) were significantly higher than those in control (132.33±36.75 and 128.79±41.24 pg/mL) and sham (136.56±45.80 and 129.85±36.14 pg/mL) groups, P<0.05 for all. EAS could decrease the release of PGE2. Plasma PGE2 levels in EAS group at T2 and T3 (41±5 and 40±5 pg/mL respectively) were significantly lower than those in control (64±5 and 62±7 pg/mL) and sham (66±6 and 62±6 pg/mL) groups. Plasma 5-HT levels in EAS group at T2 (133.66±40.85) and T3 (154.66±52.49 ng/mL) were significantly lower than those in control (168.33±56.94 and 225.28±82.03) and sham (164.54±47.53 and 217.74±76.45 ng/mL) groups. For intra-group comparison, plasma 5-HT and PGE2 levels in control and sham groups at T2 and T3, and β-EP in EAS group at T3 and T4 were significantly higher than those at T1 (P<0.05); PGE2 and 5-HT levels in EAS group showed no significant difference among the different time points (P>0.05). No apnea or severe hypotension was observed in any group. It was concluded that intraoperative ipsilateral EAS at PC4 and PC6 provides effective postoperative analgesia for patients undergoing radical esophagectomy with remifentanil anesthesia and significantly decrease requirement for parental narcotics. The underlying mechanism may be related to stimulation of the release of endogenous β-EP and inhibition of inflammatory mediators (5-HT and PGE2).

AIM: To observe the efficacy and safety of intravitreal injection of Conbercept for the treatment of wet age-related macular degeneration( AMD) .
METHODS:Retrospective analysis. A total of 20 patients involving 22 eyes were diagnosed of wet AMD and confirmed by routine ophthalmic examination, fundus fluorescein angiography ( FFA ) and optical coherence tomography. All these affected eyes received intravitreal injection of 10 mg/ml of 0. 5mg Conbercept, once monthly, for 3 successive times during the initial treatment. The need for repeated treatment was determined according to patients'disease conditions. The patients were followed up once monthly for ≥6mo. The changes in best corrected visual acuity ( BCVA ) , central retinal thickness ( CRT ) and choroidal neovascularization ( CNV) lesion leakage of the affected eyes before and after treatment were compared and analyzed.
RESULTS:Within 1, 3 and 6mo after treatment, the mean BCVA ( logMAR ) of the affected eyes increased when compared with before treatment;the difference was statistically significant(P<0. 01). In 1, 3 and 6mo after treatment, the mean CRT of the affected eyes decreased when compared with before treatment;the difference was statistically significant(P<0. 01). During the last follow-up, FFA showed that macular CNV lesion leakage disappeared in 20 eyes(90%) while leakage mitigated in 2 eyes ( 9%) . During the follow - up, there were no treatment - related serious ocular complications and systemic serious adverse reactions.
CONCLUSION: Clinically, intravitreal injection of Conbercept for the treatment of wet AMD can increase visual acuity of the affected eyes. It also can decrease CRT of the affected eyes, and inhibit neovascular leakage. There are no treatment-related adverse reactions.