Hazardous Substances ; Risk Assessment ; methods ; Workplace

The scavenging activities of Ophiopogon japonicus for superoxide anion (O_2~(·-)) radicals by HPLC-DAD coupled with chemiluminescence(CL) was studied and the active constituents in it were screened.The aqueous extracts of Ophiopogon japonicus were divided into the ethyl ether fraction and the n-butanol fraction.Their activities were investigated respectively and the reduction of CL with the pyrogallic acid 3-amino-phthalhydrazid (luminol) Na_2CO_3/NaHCO_3 buffer (pH 11.0) system worked as an activity index of the antioxidant constituents.Major active components in Ophiopogon japonicus could be identified by HPLC-DAD-MS/MS and the reference substances.The antioxidant activities of different ingredients were evaluated by standard potency equations using quercetin as positive control.The experimental data indicated that the scavenging activities of Ophiopogon japonicus for superoxide anion (O_2~(·-)) radicals are mainly from homoisoflavone in the ethyl ether fraction.It has shown that the method for on-line detection is an advantageous tool to rapidly determinate antioxidants from complex herbs.

BACKGROUND: Tetramethylpyrazine has the protective effect against the central nervous system injury. The structural changes in Nissl bodies were regarded as a marker of neuron injury.OBJECTIVE: To investigate the effect of tetramethylpyrazine on the structure and the quantity of Nissl bodies of cerebral neurons in rat with epilepsy.DESIGN: A comparative study.SETTING: It was conducted at the Physiological Department of Medical School of Xianning College.MATERIALS: From September 2004 to March 2005, it was completed at the Anatomy Department of Tongji Medical College, Huazhong University of Science and Technology. Forty healthy SD rats aging 3-4 months, weighing (250±50) g and regardless of their gender, were selected.METHODS: Rats underwent anesthesia and craniotomy. Then their cerebral cortex were exposed for placing BL-410 Experimental System of Biological Function (TME, China) to record the bilateral EEG of the brain and the seizure in rats with penicillin-induced epilepsy group and the 10 mg/kg tetramethylpyrazine group, 20 mg/kg tetramethylpyrazine group and 40 mg/kg tetramethylpyrazine group. In control groups, the brains of rats were taken out at 1 hour after craniotomy. In penicillin-induced epilepsy group, their brains were taken out at 1 hour after penicillin-induced epilepsy. In 10 mg/kg tetramethylpyrazine group, 20 mg/kg tetramethylpyrazine group and 40 mg/kg tetramethylpyrazine group, after stable penicillin-induced epilepsy, tetramethylpyrazine was injected intraperitoneally at a dose of 10 mg/kg, 20 mg/kg and 40 mg/kg, respectively.When the greatest protective effect of tetramethylpyrazine appeared, the rats' brains were taken out. Brain sections were sliced. Nissl bodies were stained by thionine staining. Under light microscope, structures of Nissl bodies were observed and the images of Nissl bodies were quantitatively analyzed by HPIAS-1000 high acuity color pathologic diagram-writing analyzing system. In each group, the average absorbency of 15 fields was regarded as the average absorbency of Nissl bodies in that group.MAIN OUTCOME MEASURES: In all the groups, the structure and the quantity of Nissl bodies of cortical neurons in rats were studied.of the structure of Nissl bodies in external granular layer cells and external pyramidal layer cells. In control group, multi-layer blue-stained and clumplike or granule-like Nissl bodies could be observed. In penicillin-induced epilepsy group, Nissl bodies were completely resolved and disappeared. In 10 mg/kg tetramethylpyrazine group, Nissl bodies were partly or completely resolved. In 20 mg/kg tetramethylpyrazine group, the quantity of Nissl bodies was significantly increased as compared with those in penicillin-induced epilepsy group and the 10 mg/kg tetramethylpyrazine group. In 40 mg/kg tetramethylpyrazine group, the quantity and the structure of of the average absorbency of stained Nissl bodies in external granular layer cells and external pyramidal layer cells in rat cortex among all the groups.In penicillin-induced epilepsy group, the average absorbency were dramatically lower than that in control group (0.033±0.002, 0.756±0.035, t=4.93,P ＜ 0.01). In 20 mg/kg tetramethylpyrazine group and 40 mg/kg tetramethylpyrazine group, the average absorbency were significantly higher than that in penicillin-induced epilepsy group (0.435±0.011, 0.658±0.029, t=2.98,5.32, P ＜ 0.01). In 40 mg/kg tetramethylpyrazine group, the average absorbency were similar to that in control group (t=1.75, P ＞ 0.05).CONCLUSION: Tetramethylpyrazine can significantly elevated the concentration of Nissl bodies of neurons in rats with epilepsy. Changes in the structure and quantity of Nissl bodies of cerebral neurons may be closely associated with seizure, and tetramethylpyrazine can restore the structure and the quantity of Nissl bodies of neurons, regulate their functions and hereby, inhibit seizures.

Background A preliminary study determined an application of manganese ion eyedrops in tracing observation of visual system in vivo,but whether manganese ion has toxic effects on ocular anterior segment tissues is still unclear.Objective This study was to investigate the toxic effects of different concentrations of manganese ion eyedrops on ocular anterior segment tissues.Methods Thirty-two clean New-Zealand white rabbits were divided into 1.00 mol/L MnCl2 group,0.50 mol/L MnCl2 group,0.25 mol/L MnCl2 group and normal control group according to random number table.The experimental eye was randomly chosen from each rabbit for eyedrops application.The manganese ion eyedrops at concentration of 1.00 mol/L,0.50 mol/L or 0.25 mol/L was topically administered in any lateral eye of each rabbit in the 1.00 mol/L MnCl2 group,0.50 mol/L MnCl2 group,0.25 mol/L MnCl2 group,and normal saline solution was used in the same way in the normal control group.In 2 hours,1 day and 3,7,14,21,28 days after eyedrops application,the irritative response of ocular surface was examined under the slit lamp microscope,and corneal damage was evaluated by corneal fluorescence staining,and corneal endothelial cell density (ECD) and corneal thickness were assessed using corneal specular microscope.The eyeball samples were prepared in 3,7,14 and 28 days after eyedrops application and hematoxylin and eosin staining was performed for histopathological examination of conjunctiva,cornea,trabecular meshwork and ciliary body tissue.The use and care of experimental animals complied with the Statement of ARVO.Results Severe hyperemia and edema in palpebral conjunctiva appeared in the 1.00 mol/L MnCl2 group and 0.50 mol/L MnCl2 group,and the symptoms reached a maximum level 1 day after eyedrop application and disappeared 7 days after eyedrops application in the 1.00 mol/L MnCl2 group.These symptoms were milder in the 0.50 mol/L MnCl2 group in comparison with the 1.00 mol/L MnCl2 group.There were no ocular irritative response in the 0.25 mol/L MnCl2 group.Significant differences were found in the corneal fluorescence scores among the groups 2 hours,1 day,3 and 7 days after eyedrop application (X2 =17.350,19.200,12.200,10.140,all at P＜0.05),with the highest score in the 1.00 mol/L MnCl2 group.The ECD was not significantly different among the groups and different time points (Fgroup =0.38,P＞0.05;Ftime =1.79,P＞0.05).The corneal thickness value was significantly different among the groups and different time points (Fgroup =18.22,P＜0.05;Ftime =116.75,P ＜ 0.05).The corneal thickness value was elevated during 2 hours to 3 days after administration of eyedrops in the 1.00 mol/L MnCl2 group and closed to normal from 7 days to 28 days.The corneal thickness value was higher from 2 hours to 14 days than that in 28 days after administration of eyedrops in the 1.00 moL/L MnCl2 group,and the corneal thickness value was higher in 2 hours to 1 day than that in 28 days after administration of eyedrops in the 0.50 mol/L MnCl2 group (all at P＜0.05).Inflammatory cell infiltration and stromal edema were exhibited in conjunctival,trabecular meshwork and ciliary body tissue in the 1.00 mol/L MnCl2 group 3 days and 7 days after eyedrops application,and only inflammatory cell infiltration in conjunctival tissue in the 0.50 mol/L MnCl2 group 3 days after eyedrops application.No obvious abnormity was seen in the 0.25 mol/L MnCl2 group.Conclusions 1.00 mol/L manganese ion eyedrops has a remarkable toxic effect on ocular anterior segment tissue in rabbit.With the lowing of drug concentrations,the toxic effects were reduced.The manganese-enhanced MRI using 0.25 mol/L manganese ion eyedrops is feasibility bacause of its non-toxicity to ocular tissues.

A strain,Actinobacillus succinogenes CGMCC 1593,producing succinic acid was isolated from bovin rumen,which could pro- duces succinic acid by anaerobic fermentation.A series of morphological and biochemical characteristics and sequence analysis of 16S rDNA reveal that it belongs to Actinobacillus succinogenes.When cultured anaerobically in medium containing 60 g/L glucose as carbon source,the strain produces 25.8 g/L of succnic acid.

Objective To study the variation of acute blood pressure in different subtypes of first ischemic stroke,and investigate the influence on the prognosis.Methods A total of 710 patients with first ischemic stroke were selected.The blood pressure levels were monitored during the initial 7 hospital days.Clinical outcome was based on the combined analysis of Barthel index and the National Institute of Health Stroke Scale (NIHSS) score on the 180th day.In the subtypes of large artery atherothrombosis(LAA),cardioembolism (CE),small artery disease occlusion (SAO) were 400,160,150 cases.Logistic regression model was used to estimate the influencing factors on the prognosis.Results An U-shaped effect was observed in different subtypes between blood pressure on admission,average acute blood pressure and prognosis.In the subtypes of LAA and CE,those who had a basehne systolic blood pressure (SBP) of 140-159 mm Hg (1 mm Hg =0.133 kPa) or a baseline diastolic blood pressure (DBP) of 90-99 mm Hg on admission got good prognosis.In the subtypes of SAO,those who had a baseline blood pressure of 130/95 mm Hg on admission got good prognosis.In all subtypes,the average blood pressure of 150/95 mm Hg got good prognosis.In the subtypes of LAA and CE,those who had a baseline SBP of 120-159 mm Hg or a baseline DBP of 80-99 mm Hg within 7 d after admission got good prognosis.In the subtypes of SAO,those who had a baseline blood pressure of 140/90 mm Hg within 7 d after admission got good prognosis.In all subtypes,the average blood pressure of 140/90 mm Hg within 7 d after admission got good prognosis.Logistic regression analysis revealed that the decrease of blood pressure during the first 24 hours,deterioration within 7 d after admission,acute complication,NIHSS score on admission were the independent risk factors of prognosis,while antihypertensive therapy in the acute phase was the independent protection factor in the subtypes of LAA and CE.In the subtypes of SAO,acute complication was the independent risk factor of prognosis.Conclusions An U-shaped effect is observed in different subtypes between blood pressure on admission and prognosis.In the subtypes of LAA and CE,the decrease of blood pressure during the first 24 hours,deterioration within 7 d after admission,acute complication,NIHSS score on admission are the independent risk factors of prognosis.

Objective To investigate the expression and significance of transforming growth factor-β1 (TGF-β1) gene in bone marrow mesenchymal stem cell (BMMSC) derived from patients with multiple myeloma (MM).Methods BMMSC of 7 MM patients and 10 patients with iron deficiency anemia were cultured in vitro.The morphology of BMMSC was observed and the growth curve was portrayed according to the daily results of BMMSC proliferation.Total RNA was extracted from BMMSCs and transcription of TGF-β1 gene in BMMSC was measured by reverse transcription-PCR.Results The proliferative activity of BMMSC was not significantly different between the two groups,but expression of TGF-β1 gene of BMMSC was higher in MM patients (0.01241±0.00419) than the control group (0.00122±0.00030) (t =3.218,P ＜ 0.05).Conclusion The abnormally high expression of TGF-β31 gene in BMMSCs could contribute to the pathogenesis of MM.

Objective To analyze the clinical data of recipients over 15 years after renal transplantation,and to find the factors that affect the long-term survival of recipients after renal transplantation.Method Before June 30,2000,326 renal transplant recipients in our hospital were collected retrospectively.The risk factors which affect the survival of kidney transplant recipients and kidney were analyzed from four dimensions.A Cox model was established to analyze these multi factors.Result Cox hazard model indicated that advanced age (P=0.010,RR =1.052),AMR (P＜0.001,RR =18.311),nonadherence (P =0.001,RR =2.854),smoking (P =0.025,RR =2.097)were the risk factors for recipients' survival.Using immunosuppressive regimen FK506 + MMF+ Pred (P =0.019,RR =0.433),or CsA + MMF + Pred (P =0.019,RR =0.413) was the protective factor for recipients' survival.Nonadherence (P＜0.001,RR =5.645),and diabetes (P＜0.001,RR =3.310) were the risk factors of grafts' survival.Using immunosuppressive regimen FK506 + MMF + Pred (P＜0.001,RR =0.236),or CsA + MMF + Pred (P =0.002,RR =0.317) was the protective factor of grafts' survival.Conclusion To enhance the long-term outcome of recipients and grafts,the individualization of immunosuppressive regiments and controlling of the chronic diseases progress by changing the unhealthy life style are cutting on edge.

Objective:To explore the effect of continuous quality improvement theory on patients' satisfaction and nurses'perception of working environment.Methods:Quality nursing service satisfaction survey was conducted in 450 patients,at the same time,100 nurses were investigated for the situation of working environment.Patients' satisfaction and the status of nurses' perception of their own work environment were compared before and after the implementation of continuous quality improvement theory.Results:After the implementation of continuous quality improvement theory,both patients' satisfaction and nurses' perception of working environment were significantly improved (P ＜ 0.05).Gonclusions:Continuous quality improvement theory can improve the satisfaction of patients with high quality nursing service,and enhance the nurses' perception of their working environment.

Objective To explore the risk factors of the recurrence of ischemic stroke and to supply theoretical basis for secondary prevention.Methods 612 patients with ischemic stroke were enrolled in the study and they were followed-up for 2 years to record the stroke recurrence.According to whether the recurrent stroke occurred,all the patients were divided into the recurrent group and the non-recurrent group.Logistic regression model was used to analyze the risk factors.Results Of 612 patients,90 patients suffered from recurrent stroke and the recurrence rate after 2 years was 14.7％.In the recurrent group,age,smoking,hypertension,diabetes,fibrillation atrial history and homocysteine level were significantly higher than those in non-recurrent group (P ＜ 0.05),compliance of anti-platelet drugs was significantly lower than that in non-recurrent group (P ＜ 0.01).Multivariate analysis suggested that age,smoking,hypertension,diabetes,atrial fibrillation history,homocysteine level and compliance of anti-platelet drugs were associated with recurrence of ischemic stroke (OR value =11.14,47.38,53.11,111.12,53.11,40.98,90.12,all P ＜ 0.05).Conclusion Age,smoking,hypertension,diabetes,atrial fibrillation history,homocysteine level and compliance of anti-platelet drugs are the independent risk factors of recurrent stroke.To enhance the interference of these risk factors are helpful for preventing the recurrence of stroke.