Objective To screen the flocculatnt-producing strain from activated sludge that can treat azo dyeing wastewater effectively.Methods Screening and rescreening were used to acquire the strain which possesses high efficiency of flocculatant production and the strain was identified.The character of microbial flocculant(MBF) and the ability to treat azo dye wastewater were studied.Results A strain of high-efficiency bioflocculant-producting bacteria(AJ-6),initially identified as Alcaligenes sp,was screened.The bioflocculant produced by the strain was able to flocculate kaolin suspension with 94.4% and fly ash suspension with 98.9% respectively.The flocculation activity distribution tests showed that the active components of the bioflocculant existed in the supernatant fluid after centrifugation.It had good treatment efficiency in treating azo dyes methyl orange wastewater.The maximal efficiencies of removing CODCr and chroma from the wastewater were 81.3% and 94.2%.Compared with the other flocculants,the performance of MBF was better than that of polyacrylamide(PAM),aluminum sulfate,ferrous sulfate.The MBF was more thermostable when treated with 100 ℃ for 30 min,and the animal toxicity test showed that the MBF had no acute toxicity to mice.Conclusion The bioflocculant produced by the strain AJ-6 is applicable to treat azo dyeing wastewater and can be also used for the other wastewater.

Objective To know the levels of polychlorinated dibenzo-p-dioxins(PCDDs),polychlorinated dibenzo-p-furan (PCDFs)and polychlorinated biphenyl(PCBs)in milk and milk powder.Methods From Feb.2007 to Jun.2007,the milk and milk powder samples were collected and PCDDs,PCDFs and PCBs were extracted from the samples by Soxhlet extraction,cleaned up by FMS and quantified by HRGC-HRMS,using isotope dilution methodology.Results PCDDrFs and PCBs were detected in all samples.The mean levels of PCDD/Fs and dl-PCBs TEQ in the milk powder were 0.43 pg/g lipid(median:0.34 pg/g lipid),and in the packed milk were 3.83pg/g)lipid(median:2.04 pg/g lipid).The mean levels of PCDD/Fs and dl-PCBs TEQ in all samples were 2.13 pg/g lipid(median:0.815 pg/g lipid).The levels of PCDD/Fs and dioxin-like PCBs in the detected samples were far below the limitation of EU except of two milk samples,and the levels of PCDD/Fs and dioxin-like PCBs were higher in the packed milk than those in the milk powder.Conclusion Some of the milk and milk powder in the investigated city has been polluted by polychlorinated dibenzo-p-dioxins(PCDDs),polychlorinated dibenzo-p-furan(PCDFs)and polychlorinated biphenyl(PCBs).

Accidents, Occupational ; Chronic Disease ; Hexanes ; poisoning ; Humans ; Shoes

Hematopoietic Stem Cell Transplantation ; Histocompatibility Antigens Class I ; genetics ; Humans ; Polymorphism, Genetic ; Transplantation, Homologous

BACKGROUND:Immunity of fetal liver stem cel transplantation is rarely reported, syngeneic and al ogeneic fetal liver stem cel transplantation in the treatment of hepatic cirrhosis is stil unclear.
OBJECTIVE:To observe the therapeutic effects of syngeneic and al ogeneic fetal liver stem cel transplantation on hepatic cirrhosis as wel as immune rejections during the therapeutic process.
METHODS:The fetal liver stem/progenitor cel s from BALB/c and C57BL/6 mice were isolated and purified by the type IV col agen enzyme digestion method. A total of 104 healthy BALB/c mice were randomly assigned to four groups. Normal control group:no treatment;Hepatic cirrhosis group, syngeneic transplantation group and al ogeneic transplantation group:16 weeks after hepatic cirrhosis models of mice were developed by intraperitoneal injection with carbon tetrachloride, physiological saline, syngeneic fetal liver stem cel s and al ogeneic fetal liver stem cel s were injected via the caudal vein. Final y, the survival statuses, liver function, hepatic fibrosis index, the number and ratio of immune cel s (CD4+T, CD8+T, NK, NKT) and histopathologic examinations were compared in each group after transplantation 4 weeks.
RESULTS AND CONCLUSION:The survival rates in the two transplantation groups were both 100%, which was significantly higher than that in the hepatic cirrhosis group (67%, P<0.05). The liver function and liver fibrosis index in each group did not show statistical differences (P>0.05). Immunological tests showed no difference between groups (P>0.05). Pathohistology examination of hepatic tissue repair:Al ogeneic transplantation group>syngeneic transplantation group>hepatic cirrhosis group. Hence, fetal liver stem cel transplantation via the caudal vein could elevate the survival rate of hepatic cirrhosis mice, al eviate the degree of hepatocyte necrosis. There is no immunologic rejection during syngeneic and al ogeneic fetal liver stem cel transplantation that could help to treat hepatic cirrhosis in mice.

The recent studies have suggested that matrix metalloproteinases(MMPs)are close associated with the instability of atherosclerotic plaques,the formation and development of intracranial aneurysm,ischemic stroke and hemorrhagic transformation.The study and application of MMP inhibitor may become a new approach in the treatment of cerebrovascular diseases.

Objective To explore the effect of lysophosphatidic acid(LPA)on blood-brain barrier(BBB) permeability and its possible mechanism.Methods LPA or LPA+suramin(L+S)were stereotaxically injected into the right eaudate nucleus in SD rats in vivo.Evans blue(EB)was used to quantitatively measure the permeability of BBB at different time points.The expression of matrix metalloproteinase-9 was detected by immunohistochemistry technique.The pathological ultrastruetural changes of BBB were assessed by transmission electron microscopy.Results The BBB permeability began to increase after LPA administered into ipsilateral eaudate nucleus,and reached the peak at 24h.Then the permeability of BBB gradually lowered after 48h.In comparison with the same time points of control group,there were quite significant differences(P＜0.01).After L+S was injected,the change of BBB permeability had differences in comparison with those of LPA group in the same time points,(P＜0.05).MMP-9 positive cells were mainly vascular endothelial cells.The numbers of MMP-9 positive blood vessels grew at 6h in LPA group,and the expression of it reached maximum at 24h,then the number of it decreased at 48h,showing significant statistical differences in comparison with the L+S group(P＜0.01),It was observed microscopically that ultrastrueture of BBB of the LPA group was changed sharply,such as basement membrane roughed and fragmented,astroeyte end-feet swolled markedly and perivaseular space enlarged obviously.But there were no remarkable changes in BBB in L+S group.Conclusion LPA can induce increase of BBB permeability and its possible mechanism is the strong expression of MMP-9 protein produeted by endothelial cells through the mediation of LPA receptor,leading to degradation of basement membrane.

Objective To evaluate the effect of recombinant human erythropoietin (rHuEPO) on brain injury in the patients undergoing cardiac valve replacement with cardiopulmonary bypass (CPB).Methods Forty-five patients with chronic valvular heart disease,aged 36-62 yr,weighing 42-92 kg,of American Society of Anesthesiologists physical status Ⅱ or Ⅲ,with New York Heart Association of Ⅱ or Ⅲ,undergoing cardiac valve replacement with CPB,were randomly divided into 3 groups (n =15 each) using a random number table:control group (group C),and different doses of rHuEPO groups (EPO1 group,EPO2 group).In EPO1 and EPO2 groups,rHuEPO 40 and 80 IU/kg were injected intravenously before anesthesia induction,respectively.Before anesthesia induction (T0,baseline value),immediately after endotracheal intubation (T1),immediately after aortic cannulation (T2),immediately after cannulation of superior and inferior vena cava (T3),immediately after the beginning of CPB (T4),when each index was decreased to the minimal value during CPB (T5),after rewarming to 36.5 ℃ (T6),immediately after termination of CPB (T7),and at 1 h after termination of CPB (T8),regional cerebral oxygen saturation (rSO2),tissue hemoglobin index (THI),and changes in concentrations of oxyhemoglobin (△ O2Hb),deoxyhemoglobin (△ HHb) and total hemoglobin (△ cHb) in bilateral frontal lobes were recorded.The patients whose minimal rSO2 ≤ 50％ and decrease in minimal rSO2 ≥ 20％ of the baseline value (△rSO2) were recorded.At T0,T8 and 2 h after termination of CPB (T9),venous blood samples were taken for determination of serum concentrations of S100 protein and neuron-specific enolase (NSE) by ELISA.At 1 day before surgery and 8 days after surgery,the patient's cognitive function was assessed using Mini-Mental State Examination,the Digit Span subtest of the Wechsler Adult Intelligence Scale-Revised (WAIS-R),the Digit Symbol subtest of the WAIS-R,the Trailing Making Test (Part A)and the Stroop Color Word Interference Test,while depression and anxiety were assessed by Zung Self-Rating Depression Scale and Zung Self-Rating Anxiety Scale,respectively.The occurrence of postoperative cognitive dysfunction was recorded.Results There was no significant difference among the three groups in bilateral rSO2 and △ cHb,incidence of bilateral rSO2 ≤ 50％ and postoperative cognitive dysfunction,Zung Self-Rating Depression Scale score,and Zung Self-Rating anxiety Scale score at each time point (P＞0.05).Compared with group C,the incidence of left △ rSO2 ≥ 20％ was significantly decreased,the right △ O2 Hb was increased at T6,8,the serum NSE concentrations were decreased at T9,the serum S100 protein concentrations were decreased at T8,and the number of the Digit Symbol subtest of the WAIS-R completed was increased in group EPO1,and right THI was significantly decreased at T2,T3,T5,T7 and T8,right △ HHb was increased at T2 and T3,and the completion time of Stroop color word interference test B was shortened at 8 days after surgery in group EPO2 (P＜0.05 or 0.01).Compared with group EPO1,the incidence of left △rSO2 ≥ 20％ was significantly increased,the right THI was decreased at T2-4 and T6-8,and the left △ O2 Hb at T6-7 and right △ O2 Hb at T8 were decreased in group EPO2 (P＜0.05).Conclusion rHuEPO 40 IU/kg injected intravenously before induction of anesthesia can mitigate brain injury in the patients undergoing cardiac valve replacement with CPB.

Objective To explore the value of echocardiography in percutaneous left atrial appendage (LAA)closure for stroke prevention in patients with nonvalvular atrial fibrillation during procedure and for short-term follow-up.Methods Twenty patients were enrolled to undergo percutaneous LAA closure with the LAmbre device.Rheumatic valvular diseases were excluded by transthoracic echocardiography (TTE) and transesophageal echocardiography(TEE)before the closure procedure.TEE was performed during the procedure for the trans-septal puncture and the release of the closure device.Combined TEE with angiographic measurements,guidance for the optimal device size was provided.The closure effect and procedure-related complications were observed immediately by TEE and also evaluated by TTE at 1-day and 1-month follow-up.Results All patients underwent LAA occlusion successfully.TEE color Doppler evaluation have shown nine patients with complete closure immediately,one with a ≤ 1 mm residual LAA leak,and ten with a 1 -3 mm jet.There were no other complications during the procedure.One day after the closure,small pericardial effusions were observed for three patients while two of the three were free of the pericardial effusion at the 1-month follow-up.During the short-term follow-up,no damage was found at any anatomical structures near LAA due to the closure process,and there was no significant difference of cardiac function before and after the procedure.Conclusions With the guidance of TEE,the successful rate of percutaneous LAA closure procedure was preferable and the occurrence rate of compliance was acceptable. And TTE played an important role in patients'short-term follow-up.

Background One of the difficulties in identifying early glaucoma is the variability of perimetry performance.For this reason,a field defect have to be reproduced more than two consecutive examinations before it is confirmed.The relationship between visual field sensitivity and retinal nerve fiber layer (RNFL) thickness may give us a more efficient and objective assessment to the early diagnosis of glaucoma.Objective This diagnostic test was to evaluate the application of functional-structural relationship between automated perimetry and RNFL in the early diagnosis of open-angle glaucoma.Methods Sixty-four eyes of 64 patients with early open-angle glaucoma and 50 eyes of 50 normal volunteers with the matched age and gender were enrolled in Xiangya Hospital January to June 2007.Visual field examinations,including standard automated perimetry (SAP),short wave automated perimetry (SWAP),and imaging of scanning laser polarimetry with variable corneal compensation(GDxVCC),were performed on the subjects with the informed consent.The sensitivity and specificity of the joint or single measurement of GDxVCC,SAP and SWAP under the local diagnostic criteria,and overall diagnostic criteria were calculated.Results According to the overall diagnostic criteria,the sensitivity of GDxVCC,SWAP and SAP were 70％,63％,61％ respectively,and the specificity were 84％,80％,78％,respectively.According to the local diagnostic criteria,the sensitivity of GDxVCC,SWAP and SAP were 78％,86％,78％,respectively,and the specificity were 54％,40％,50％,respectively.With the local diagnostic criteria,the sensitivity and specificity of serial test of GDxVCC,SWAP and SAP were 86％ and 90％ respectively,and the positive likelihood ratio and negative likelihood ratio were 8.59 and O.16,respectively.Conclusions The functional-structural relationship between automated perimetry and RNFL which can provide valuable individual diagnostic information for patients,and serial test of GDxVCC,SWAP and SAP can reduce the false positive rate and improve the diagnostic performance significantly.