China ; Industry ; standards ; Occupational Health Services ; standards ; Reference Standards

A method of streptomycin resistance screening was applied to improve t he productivity of Natamycin by Streptomyces gilvosporeus(ATCC13326) The sp ores treated with UV light were regenerated on agar plates containing 0 6?g/mL stre p tomycin 122 streptomycin resistant(str) mutants were obtained The Natamycin y iel ds of 13 mutants were higher than the original strain The mutants with high Na t amycin productivity were screened at a high frequency(10 6%) The highest one that demonstrated 1 46 times that of the original strain in Natamy cin productivity was obtained

OBJECTIVE:To study the preparation of the ligustrazine hydrochloride liposome and evaluate its quality.METHODS:The liposome was prepared by various methods on a trial basis.The entrapped efficiency(EE)of the liposome derived from passive loading and active loading was compared.RESULTS:The ammonim sulfate gradient technology had the highest EE of 48.63%and its mean size was 6.5?m and the pH was 5.93.It was stable in refrigeratory(4℃～10℃)storage for 30 days.CONCLUSION:The ammonim sulfate gradient technology of preparation of the ligustrazine hydrochloride liposome is feasible.

ObjeCtive To investigate the value of protein biochip in the diagnosis of Lyme borreliosis. Methods The serum IgM and IgG antibodies against flagellin were detected by flagellin coated-and N-hydroxysuccinimide (NHS) modified-biochips in 82 patients with neuroborreliosis (NB),35 patients with erythema migrans (EM) and 44 normal controls.The results were compared with those from enzyme-linked immunosorbent assays (ELISA) and Western blot.Results The levels of both IgM and IgG antibodies were significantly higher in the NB patients than those in the normal controls (P

Humans ; Metals ; Microwaves ; adverse effects ; Occupational Exposure ; adverse effects ; analysis ; Workplace

Objective:To prepare the egg yolk immunoglobulin Y ( IgY) against human Sucrase and study its stability,in vitro activity. Methods:Hy-line laying hens were immunized with human Sucrase protein,IgY was isolated and purified from egg yolks of im-munized hens using water dilution and salting out method. Indirect ELISA was used to evaluate the titer and stability of IgY. The purity and specificity of IgY were analysed by SDS-PAGE and Western blot respectively. The inhibitory effects of IgY on α-glucosidase was studied by PNPG method. Results:Indirect ELISA results showed IgY could be detected on the tenth day after the first immunization, and the peak titer of IgY was 1:12 800 after the 40th day of immunization. SDS-PAGE showed that the heavy chain and light chain of IgY were 65 kD and 25 kD respectively, and the IgY against human Sucrase could specifically recognize the protein of human Sucrase. The IgY maintained primary titer when it was kept between 29-69℃ for 15 min,and pH 4-7,37℃,4 h. The titer of IgY was maintained 50% after digestion by pepsin and trypsin respectively for 2 hours. IgY had a higher resistence to pepsin than trypsin after longer digestion time. IgY showed an inhibitory effect on α-glucosidase in concentration dependent manner. The half inhibitory concentration (IC50) was 0. 540 mg/ml. Conclusion:The IgY against human Sucrase has been successfully obtained,which established foundations for its study of Type 2 diabetes mellitus rat models in vivo.

Objective To integrate urine strip chemistry analysis with urine sedimental analysis and set up the criteria for urine microscopy review following automated urine analysis.Methods A total of 1 714 urine samples were collected from Peking Union Medical College Hospital from November 2008 to October 2010.Out of 1 714 samples, 1 300 samples were used for the establishment of review criteria, and 214 samples were used for criteria verification.The other 200 samples from healthy donors were used to set up the normal reference range of fully automated urine sedimental analyzer UF-1000i.RBC,WBC,PRO and CAST in all the samples were measured by Siemens Bayer Clinitek 500 urine strip chemistry analyzer, Sysmex UF-1000i urine sedimental analyzer and microscopic examination.Based on the different laboratory automation in urine analysis, four microscopic review protocols were defined: (1) Protocol 1: based on chemistry results only, microscopy review was performed when any of WBC, RBC and PRO was positive; (2) Protocol 2: based on fully automated sedimental analyzer only,microscopy review was performed when any of WBC, RBC and CAST was over the upper limit of the reference range; (3) Protocol 3: All the results of urine chemistry analyzer and sedimental analyzer were integrated.If two WBC results were different between two systems (in one system WBC was positive or over the upper limit of the reference range but in another system WBC was negative or within the reference range), and any of RBC, PRO/CAST was positive or over the upper limit, microscopic review was performed; (4) Protocol 4: if any of WBC, RBC, PRO/CAST was different between two systems, microscopic review was performed.Review criteria were performed with Sysmex Laboman UriAccess 3.0 software.Results The reference ranges of UF-1000i parameters were RBC 0-7.5/μl (male), 0-15.9/μl (female); WBC 0-11.6/μl (male), 0-12.7/μl (female); Epithelial cell were 0-6.5/μl (male), 0-21.4/μl (female); CAST 0-1.3/μl.The results of microscopic examination revealed that positive samples were 47.46% (617/1 300) and negative samples were 52.54% (683/1 300). Among positive samples, majority showed the presence of RBC (60.13%,371/617), followed by CAST (8.43%,52/617).The false negative rates of four protocols were 8.38% (109/1 300), 4.69% (61/1 300), 0.62% (8/1 300) and 0.54% (7/1 300), respectively.The review rates were 47.85% (622/1 300), 59.38% (772/1 300), 72.85% (947/1 300) and 52.23% (679/1 300), respectively.Although there were false negative cases in protocol 4, all the patients had normal serum creatine level.In those 214 patients for verification, the false negative rate using protocol 4 was zero, the review rates were 53.74% (115/214).Conclusions Protocol 4 shows lest false negative rate and lower review rate.Importantly, there was no patients with serious renal function abnormality missed using protocol 4.Therefore, protocol 4 is an ideal criteria for microscopy review following automated urine analysis.

Objective To evaluate the protective effect of astragaloside Ⅳ against ultraviolet B (UVB)-induced photodamage to human HaCaT keratinocytes,and to investigate its mechanisms.Methods Culturedimmortalized human HaCaT keratinocytes were divided into four groups:blank control group receiving untreated,UVB group irradiated with 50 mJ/cm2 UVB,astragaloside Ⅳ group treated with astragaloside Ⅳ,UVB + astragalosideⅣ group treated with astragaloside Ⅳ for 24 hours before and after 50 mJ/cm2 of UVB radiation.The concentration ofastragaloside Ⅳ ranged from 10 to 200 mg/L in cell proliferation assay,and according to the results of proliferationassay,20 mg/L was determined as the optimal concentration in the other assays.At 24 hours after UVB radiation,cellcounting kit-8 (CCK8) assay was performed to evaluate cellular proliferative activity,flow cytometry to determineintracellular reactive oxygen species (ROS) levels,and Western blot to measure the expression levels of p53,p38,matrix metalloproteinase-9 (MMP-9) and high mobility group Al (HMGA-1) protein in HaCaT cells.ResultsCompared with the control group,astragaloside Ⅳ at 10 and 20 mg/L had no inhibitory effect (F =1.32,P ＞ 0.05),while astragaloside Ⅳ at 50,100 and 200 mg/L showed significantly inhibitory effect (F =20.20,P ＜ 0.05),on theproliferation of HaCaT cells.In addition,cellular proliferative activity in the UVB group was significantly lower thanthat in the control group (F =99.00,P ＜ 0.01).Compared with the UVB group,cellular proliferative activityincreased to different degrees in HaCaT cells treated with both UVB and astragaloside Ⅳ of 10-200 mg/L (F =19.08,P ＜ 0.01),with the strongest increase observed in those treated with UVB and astragaloside Ⅳ of 20 mg/L.Further experiments revealed reduced intracellular ROS levels in the UVB + astragaloside Ⅳ (20 mg/L) groupcompared with the UVB group (t =21.12,P ＜ 0.01).Western blot assay showed that the expression levels of p53,p38,MMP-9 and HMGA-1 protein were significantly higher in the UVB group than in the control group (all P ＜0.01),but significantly lower in the UVB + astragaloside Ⅳ (20 mg/L) group than in the UVB group (all P ＜ 0.01).Conclusion Astragaloside Ⅳ can effectively protect keratinocytes from UVB-induced photodamage.

Objective To evaluate the effect of carbon monoxide-releasing molecule-3 (CORM-3) on oxygen-glucose deprivation and restoration (OGD/R) injury to rat cardiomyocytes.Methods Cardiomyocytes isolated from the hearts of pathogen-free Sprague-Dawley rats (aged 1-3 days) were primarily cultured for 4 consecutive days and then divided into 6 groups (n=36 each) on the 5th day using a random number table:control group (group C),OGD/R group,OGD/R plus inactivated CORM (iCORM-3) 50 μmol/L group (group iC),OGD/R plus CORM-3 12.5 μmol/L group (group C1),OGD/R plus CORM-3 25.0 μmol/L group (group C2),and OGD/R plus CORM-3 50.0 μmol/L group (group C3).The cardiomyocytes were incubated in glucose-and serum-free DMEM for 3 h and then in low-glucose DMEM for 6 h.At the beginning of oxygen-glucose deprivation,the corresponding concentrations of CORM-3 were added to the glucose-free DMEM in C1,C2 and C3 groups and iCORM-3 (final concentration 50 μmol/L) were added to the glucose-free DMEM in group iC,and the glucose-free DMEM with the intervention drug was abandoned immediately after restoration of oxygen and glucose supply.At 6 h after restoration of oxygen and glucose supply,the pathological changes of cardiomyocytes were observed,cell proliferation was measured by CCK-8 assay,the activity of lactate dehydrogenase (LDH) in the supernatant was determined by lactic acid-pyruvate method,and the early apoptosis rate of cells was detected by flow cytometry.Results Compared with group C,the cell proliferation was significantly reduced,and the LDH concentration in the supernatant and early apoptosis rate were increased in the other five groups (P＜0.05).Compared with OGD/R and iC groups,the cell proliferation was significantly increased,and the LDH concentration in the supernatant and early apoptosis rate were decreased in C1,C2 and C3 groups (P＜0.05).The cell proliferation was significantly lower,and the LDH concentration in the supernatant and early apoptosis rate were higher in C2 and C3 groups than in group C1 (P＜0.05) and in group C3 than in group C2 (P＜0.05).The pathological changes of cardiomyocytes were significantly attenuated in C1,C2 and C3 groups,especially in group C1.Conclusion CORM-3 can reduce OGD/R injury to cardiomyocytes of rats,and the effect is gradually weakened with the increasing concentration.

The protoplasts of original Aspergillus niger strain Uco-3 were treated with the cooperation of UV and ?-ray to obtain the high-yielding strain producing the thermostable ?-galactosidase. Under the optimum conditions of formation and regeneration protoplasts were prepared. According to the interaction of positive mutation rate and radiation dose,the optimum condition was determined. The optimum dose of UV was 4 minutes and the optimum dose of ?-ray was 500 Gy. After mutagenetic treatment of protoplasts and selection from a lot of mutants,a mutant DL116 producing the thermostable ?-galactosidase was obtained. The ?-galactosidase activity of DL116 was increased from 16.27 U/mL to 44.37 U/mL,which was higher than that of strain Uco-3.