1.Determination of furbenicillin sodium and its related substances by HPLC.
Yan CHANG ; Ye TIAN ; Yue MA ; Chang-qin HU
Acta Pharmaceutica Sinica 2015;50(12):1632-1636
Furbenicillin is a broad-spectrum semisynthetic penicillin with strong antibacterial activity against Gram-negative bacteria. Furbenicillin sodium is determined by volumetric method in current criteria. However, the criteria does not contain an assay of related substances of furbenicillin sodium. In this study, we established a method for detection and analysis of furbenicillin sodium and its related substances by HPLC. The analysis was performed with a C18 column under a gradient elution, the detection wavelength was 225 nm, and the column temperature was 35 degrees C. The reliability and accuracy of established method was validated in this study. Pure samples of furbenicillin sodium and its related substances were prepared. The structures, biological activities, and chromatographic retention behaviors of furbenicillin sodium and its related substances were identified using NMR, CLSI agar dilution method, and HPLC. All results in the current study provide ample evidence that this method is able to determine the reasonable limits in the quality-control protocol for furbenicillin sodium.
Anti-Bacterial Agents
;
chemistry
;
Chromatography, High Pressure Liquid
;
Magnetic Resonance Spectroscopy
;
Penicillins
;
Quality Control
;
Reproducibility of Results
2.The role of cell density in the morphology of the Candida albicans bioflims development and the tyrosol production
Xin WEI ; Guanling WU ; Weihong LIU ; Yan ZHANG ; Qin HU
Chinese Journal of Microbiology and Immunology 2010;30(4):344-348
Objective To study the role of cell density in the tyrosol production and morphology for Candida albicans biofilms. Methods C. albicans SC5314 and clinical isolates were propagated in yeast peptone dextrose (YPD) medium. Cells were collected by centrifugation and washed twice in sterile phosphate-buffered saline (PBS) before this study, then resuspended in RPMI 1640 supplemented with L-glutamine and adjusted to a desired concentration of 5 × 10~6 cells/ml, 5×10~5 cells/ml, 5 × 10~4 cells/ml, 5 × 10~3 cells/ml after counting with a hematocytometer. Standardized C. albicans cells were prepared as above description and 2000 μl of this standardized cell suspension was dispensed into the wells, then C. albicans biofilms were formed on the bottom of the polystyrene wells. In this study, tyrosol synthesized by SC5314 and clinical isolates of C. albicans biofilm was quantified by high performance liquid chromatography (HPLC). The effects of tyrosol on morphology of C. albicans biofilms were investigated by scanning electron microscopy (SEM). Results Tyrosol production of C. albicans biofilms was affected by cell densities. At lower inoculation size(5 μ 10~3 cells/ml), there was too less tyrosol production to be detected at the early stage of the biofilms formation. At higher inoculation size (5 μ10~6 cells/ml), tyrosol can be detectable at the early stage or at the mature stage of biofilms formation. There was a sharp increase in tyrosol concentration at 24 h, while there was a decrease in tyrosol concentration after that time from the strains when the strains were at an inoculation size of 5 × 10~6 cells/ml and 5 × 10~5 cells/ml. Cell densities affected the morphology formation of the C. albicans biofilms. At the early stage of the biofilms formation, C. albicans grew less germ tube at lower cell densities than that at the higher cell densities. With the mature of the biofilms, C. albicarts grew more hyphae at higher cell densities than that at the lower cell densities. All these above showed that cell densities played an important role in the propagation for the C. albi-cans in the biofilm formation. Conclusion Cell density play an important role in the formation of the C. albi-cans biofilms and the production of the tyrosol.
3.Qualitative study on preventive strategies of unplanned endotracheal extubation among adult patients
Xiangyu GE ; Xiaoling ZHU ; Yan HU ; Jianming XU ; Wei QIN
Chinese Journal of Practical Nursing 2014;30(28):6-9
Objective To understand the available preventive strategies of unplanned endotracheal extubation (UEX) among adult patients.Methods Twelve nurses were in-depth interviewed and data were processed and analyzed using categorization analysis method.Results Major themes were identified as follows:the incidence rate of UEX,tube fixation,efficacious physical restraint,appropriate sedation and training for younger nurses.Conclusions Nursing leaders should further standardize nursing process related to prevention of UEX,strengthen training for nurses,choose appropriate fixation method for patients and promote physical restraint and sedation care to prevent UEX and improve patient clinical outcomes.
4.Clinical and imaging characteristics of posterior reversible encephalopathy syndrome in children with acute lymphoblastic leukemia after chemotherapy induction
Jihong TANG ; Yan LI ; Qin GU ; Mao SHENG ; Shaoyan HU
Chinese Journal of Applied Clinical Pediatrics 2015;30(24):1863-1867
Objective To investigate the clinical features, brain imaging significance and the possible pathogenesis of posterior reversible encephalopathy syndrome (PRES) in childhood acute lymphoblastic leukemia (ALL) followed by chemotherapy induction.Methods The diagnosis and treatment of ALL were performed according to the guidelines of the Pediatric Association of Chinese Medical Association.There were 11 cases of pediatric ALL who developed PRES after chemotherapy induction.The clinical presentations, initial and follow-up radiologic features, and the neurologic outcomes of these 11 cases were investigated for one-year follow-up.All patients were reexamined 1,3,6, and 12 months after first imaging.Results Headache (10/1 1 cases), epileptic seizure (7/11 cases), high blood pressure (4/11 cases) ,visual impairment (6/11 cases) ,disturbance of consciousness (5/11 cases) and walking instability (2/11 cases) were the most common symptoms of these ALL patients with PRES.Magnetic resonance imaging (MRI) scanning revealed that lesions were mainly distributed in occipital lobe (9/11 cases), parietal lobe (8/11 cases), frontal lobe (5/11 cases) ,temporal lobe (3/11 cases), the deep white matter of bilateral periventricular and centrum semiovale (2/11 cases) and hemisphaerium cerebelli (1/11 cases).The radiological findings indicated that lesions had multifocal,symmetrical and posteriorly distributed characteristics in the cerebral hemispheres.After the diagnosis of PRES,patients stopped chemotherapy courses promptly and received symptomatic treatment, and then the clinical and imaging symptoms of most cases gradually disappeared.After 1-year follow-up,9 patients had good prognosis and no sequelae, 1 patient had symptomatic epilepsy (brain magnetic resonance imaging scan showed lesions in the left temporal lobe) ,and 1 patient had slight visual impairment.After the craniocerebral symptoms disappeared clinically ALL chemotherapy continued in all patients and no recurrent PRES was observed.Conclusions Although the clinical and imaging features of PRES may be diverse ,PRES should be recognized as a possible important complication of ALL when neurological symptoms appear.However, PRES is reversible when the patients are diagnosed and treated at an early stage.Thus,the occurrence of PRES should be considered and investigated to optimize the early induction schemes for ALL treatment.
5.Expression of aquaporins-4 in brain tissue of rats with pancreatic encephalopathy
Yan ZHAO ; Haili QIN ; Gouyong HU ; Chuanyong GUO ; Xingpeng WANG
Chinese Journal of Pancreatology 2011;11(5):349-351
Objective To study the expression of aquaporins-4 (AQP4) in the brain tissue of rats with pancreatic encephalopathy (PE) induced by phospholipase A2 and to explore the role of aquaporins-4 in PE.Methods Twenty five healthy Wistar rats were randomized into 3 groups:blank group ( n =5),PE group (n =10 ) and control group (n =10 ).The experimental model was established in rats by injecting phospholipase A2 into carotid artery (0.1 ml/100 g body weight).Same amount of normal saline was used in the control group and no treatment was used in the blank group.One day later,the rats were sacrificed,then the measurement of brain tissue wet/dry (W/D) weight ratio was performed,and brain tissue was routinely pathologically examined,immunohistochemistry and Western blotting were performed in each group to detect the expression of aquaporins-4.Results There was no obvious brain tissue pathological change in the control group and blank group.Neurons in the brain tissue of PE rats presented with significant edema and ballooning degeneration,infiltration of inflammatory cells,leukocyte aggregation around the microvessels.The water contents in the brain tissue in the blank group and control group,PE group were (61.44 ±0.36)%,(63.20±0.32)% and (78.33 ±0.24)%,and it was significantly higher in PE group than that in the control and blank group (P<0.05).The expressions of aquaporins-4 in the brain tissue were 0.41 ±0.27,0.49 ±0.13,0.98 ±0.21,respectively,and it was significantly increased in PE group than that in the control and blank group (P < 0.05 ).Conclusions Aquaporins-4 may play important roles in the pathogenesis of pancreatic encephalopathy.
6.A New Method of Armillaria mellea Isolation-Gastrodia elata Tissue Isolating Method
Bo XIAO ; Kai-Zhi HU ; Jie LIU ; Yan-Qin LIU ;
Microbiology 1992;0(03):-
This paper reported a new method of Armillaria mellea isolation-Gastrodia elata tissue isolating. Compared with normal isolating method-rhizomorph isolating method, it showed that the success rate of new method (78% ) was higher than the rhizomorph isolating method (16% ) , besides this, the new method was easier, and growth characteristic of obtained strain was superior to that obtained from rhizomorph isolating method.
7.An Electrochemiluminescence Method for Determination of Manganese (Ⅱ)
Zhengping JI ; Hongguo HU ; Bingyi YAN ; Guangxu ZHU ; Qin XU ; Xiaoya HU
Chinese Journal of Analytical Chemistry 2017;45(3):397-402
In the presence of silver ion, Mn2+ could be electro-oxidized to potassium hypermanganate in phosphoric acid solution, which could effectively react with pyrocatechol in acid solution and luminol in sodium hydroxide solution to produce chemiluminescence. On the basis of this, a novel indirect approach for the detection of Mn2+ was established. The effect of silver ions on the electrochemical oxidation of Mn2+was studied. when 1. 5 ×10-5 mol/L Ag+ and 0. 01 mol/L phosphoric acid solution were used in the process of electrochemical oxidation, the CL intensity could be up to the maximum value after the above solution was electrolyzed for 2 min. The relation of CL intensity and Mn2+concentration in the solutions at different pH and the selectivity were also investigated. when the pyrocatechol was used as luminescent reagent in the acidic medium, the CL intensity was linearly to the Mn2+concentration in the range of 1. 82×10-7-7. 27×10-5 mol/L with excellent selectivity. Common ions had little interferences in the determination of Mn2+. The method was successfully applied to the determination of Mn2+ in surface water and drinking water with satisfactory results.
8.Distribution and antimicrobial susceptibility profile of the pathogens isolated from bloodstream infections
Yanjun ZHANG ; Xiuzhen MA ; Qin QIN ; Hu LI ; Yun LIU ; Xiaochun HUANG ; Hui SHEN ; Yan CHEN ; Yuxiang WAN ; Yi HUANG
Chinese Journal of Infection and Chemotherapy 2017;17(3):314-320
Objective To investigate the distribution and antimicrobial susceptibility of the bacteria isolated from bloodstream infections during 2013-2014 in Changhai Hospital for rational use of antibacterial agents.Methods The bacterial strains from blood samples were collected during the period from January 2013 through December 2014,and subjected to antimicrobial susceptibility testing by using automated system or Kirby-Bauer method.The results were interpreted according to CLSI M100-S24 breakpoints or FDA breakpoints.The data were analyzed by WHONET 5.6 software.Results A total of 1 048 nonduplicate isolates were collected,of which Escherichia coli,coagulase-negative Staphylococcus (CNS) and Klebsiella pneumoniae accounted for 29.5%,15.8% and 13.8%,respectively.Gastroenterology,Hematology,General surgery,Urology and Department of Infectious Diseases are the top 5 departments according to their total number of bacterial isolates.The results of antimicrobial susceptibility testing showed that ESBLs-producing E.coli and K.pneumoniae accounted for 63.8% and 38.6%,respectively.The prevalence of methicillinresistant CNS (MRCNS) was 77.6%.The E.coli strains isolated from Urology showed higher resistance rates to cephalosporins than the total E.coli strains,while the E.coli strains isolated from Gastroenterology showed higher resistance rates to betalactarn/beta-lactamase inhibitor combinations and carbapenems than the total E.coli strains.Higher prevalence of MRCNS was found in departments of Hematology,Urology and Neurosurgery.All the CNS strains isolated from Neurosurgery were resistant to methicillin.The K.pneumoniae strains isolated from Bum ICU had higher resistance rates to all the antibacterial agents tested than the total K.pneumoniae strains,while the K.pneumoniae strains isolated from Gastroenterology showed higher resistance rates to carbapenems and tigecycline than the total K.pneumoniae strains.Conclusions The pathogenic bacteria isolated from bloodstream infections vary with departments in terms of species distribution and antimicrobial susceptibility profile.It is necessary to strengthen the surveillance of antimicrobial resistance in hospital for rational use of antibiotics.
9.The expression and clinical significance of circulating tumor cells in small-cell lung cancer
Cheng QIAN ; Mingli GU ; Chaoping FANG ; Lei SHI ; Hu LI ; Yan CHEN ; Chuanlu REN ; Qin QIN ; Anmei DENG
Chinese Journal of Laboratory Medicine 2014;(5):362-364
Objective To investigate the expression of Circulating tumor cells ( CTCs ) in peripheral blood cells of patients with different stages of Small-Cell Lung Cancer ( SCLC) ,and to evaluate its significance in early diagnosis of lung cancer metastasis.Methods Thirty-five patients with SCLC ( 12 in limited stage and 23 in extensive stage ) and 25 patients with benign lung disease were recruited at the Shanghai Changhai Hospital from April 2011 to April 2013.Samples were prepared from 7.5 ml peripheral venous blood and collected in CellSave tubes.The CTC counts were determined using CellTracks AutoPrep fluorescence scanning system according to the manufacturers′instructions.The expression of CTCs in peripheral blood of SCLC patients and benign lung disease patients were analyzed.The expression of CTCs in different stages of SCLC was measured and compared.Furthermore, samples were prepared from 2 ml peripheral venous blood by centrifugation.The serum levels of NSE Neuron specific enolase were measured.The relationship between the expression of CTC and NSE was analyzed.Results CTCs positive rates in SCLC were significantly higher than in benign lung disease controls [ Positive rates of CTC≥1 were 80.0%and 12.0%(χ2 =27.003,P<0.000 1),CTC≥5 were 51.4%and 0 (χ2 =18.367,P<0.000 1), CTC≥10 were 34.3%and 0(χ2 =10.714,P<0.001),CTC≥50 were 17.1 and 0(P=0.036,P<0.05), respectively ].CTCs positive rates in SCLC extensive stage were significantly higher than limited-stage [Positive rates of CTC≥1 were 58.3% and 91.3%(P=0.033,P<0.05), CTC≥5 were 65.2% and 25.0%(P=0.035,P<0.05), respectively].The expression of CTCs was significantly correlated with NSE (r=0.743 7, P<0.000 1).Conclusion The expression of CTC in SCLC patients is significantly higher than those in control group , and is closely related to clinical stages , which may provide new clues to early predicting of SCLC metastasis and deterioration.
10.Construction of the quantitative structure retention relationship of cefdinir related substances.
Chen WANG ; Jin LI ; Yan-chun FENG ; Ying LIU ; Chang-qin HU
Acta Pharmaceutica Sinica 2015;50(9):1161-1166
The molecular descriptors of impurities with known structure in cefdinir were calculated, selected and associated with the chromatographic retention behavior to establish a model. This quantitative structure retention relationships (QSRR) model for the related substances of cefdinir was established under specific chromatographic condition and verified by other impurities. 12 molecular descriptors were used to establish the QSRR model, F_AFRBWF, Blbn_J, SsCH3, SssCH2, SsNH2, SssNH, SssS, SHdCH2, EEM_AFc, EEM_AFpl, EEM_XFpl and Pi_MaxQ. The relativity between true values and predictions in QSRR of cefdinir is R2 = 0.9836 (n = 18), ΔRRT is no more than 0.154, as 10.17% in RRT. The results indicate that the QSRR model for the related substances of cefdinir can be used to evaluate the analysis methods for related substances and predict the chromatographic behavior of new impurities, which will provide a new way for the evaluation of the effectiveness for drug quality control.
Cephalosporins
;
chemistry
;
standards
;
Chromatography
;
Models, Chemical
;
Quality Control
;
Structure-Activity Relationship