Objective To find methods to isolate and purify plasminogen activator (Pla) from artificial culture of Yersinia pestis. Methods Ultrasonication and urea extracting combined by ammonium sulfate salting-out were tried to extract Pla. High performance liquid chromatography(HPLC) was used to purify Pla. The first step was ion exchange and the second was gel filtration, Preparative electrophoresis was used to purify Pla, too. The enzyme activity of the isolated or purificated Pla was detected. Results Both 50% - 60% saturated ammonium sulfate deposition of supernatant of plague bacilli ultrasonication and 0 - 10% saturated ammonium sulfate deposition of supernatant of plague bacilli powder soaked by urea had three bands(Mr about 31×103, 35×103 and 37×103) and lysis rings were 6.5 and 7.2 mm in diameter respectively when the enzyme activity was detected. Pla purified by HPLC was mainly composed of three bands(Mr about 31×103, 35×103 and 37×103), occupying more than 80% of total protein weight and lysis ring was 5.0 mm in diameter. Pla purified by preparative electrophoresis mainly consisted of three bands(Mr about 31×103, 35×103 and 37×103) with other proteins of low concentration nearby, no lysis ring was detected. Conclusions Pla is collected by the methods of ultrasonication and urea extracting. Priliminary purification of Pla can be achieved by HPLC and preparative electrophoresis.

Objective The purpose of this study was to develop a high-throughput micro-plate radiobinding assay (RBA) of glutamic acid decarboxylase antibody (GAD-Ab) and to evaluate its clinical application. Methods 35labeled GAD65 antigen was incubated with sera for 24 h on a 96-well plate, and then transferred to the Millipore plate coated with protein A, which was washed with 4℃ PBS buffer, and then counted by a liquid scintillation counter. The GAD-Ab results were expressed by WHO standard unit (U/ml). A total of 224 healthy controls, 162 patients with type 1 diabetes mellitus(T1DM) and 210 patients with newly diagnosed type 2 diabetes (T2DM) were recruited. A total of 119 TI DM and healthy cases with gradually changing GAD-Ab levels were selected to compare the consistency of micro-plate RBA with conventional radioligand assay (RLA). Blood samples were obtained from the peripheral vein and finger tip in 32 healthy controls, 35 T1DM and 24 T2DM patients, and tested with micro-plate RBA and then compared with the conventional RLA to investigate the reliability of finger tip sampling. Linear correlation,student's t-test, variance analysis and receiver operating characteristic (ROC) curve were performed using SPSS 11.5. Results (1) The optimized conditions of micro-plate RBA included 2 μl serum incubated with3 ×104 counts/min 35S-GAD for 24 h under slow vibration, antigen-antibody compounds washed 10 times by 4℃ PBS buffer, and radioactivity counted with Optiphase Supermix scintillation liquid. (2)The intra-batch CV of the micro-plate RBA was 3.8%- 10.2%, and the inter-batch CV was 5.6%- 11.9%. The linearity analysis showed a good correlation when the GAD-Ab in serum samples ranged from 40.3 to 664 U/ml and the detection limit of measurement was 3.6 U/ml. The results from Diabetes Autoantibody Standardization Program (DASP) 2005 showed that the sensitivity and specificity for GAD-Ab were 78% (39 positive among 50 new-onset T1DM) and 98% (2 positive among 100 healthy controls). The results of GAD-Ab obtained with micro-plate RBA and RLA were closely correlated (r=0.915,P<0.001) with a high concordance level of 97.5% and a Kappa value of 0.95. (3)TI DM and T2DM patients showed higher positive rates for GAD-Ab than the healthy controls(46.9% and 5.2% vs 0.89% ,X2=123.5 and 10. 1 ,P <0.001 and <0.01, respectively). (4)The consistency of GAD-Ab measurement with RBA using finger tip blood and RLA measurement using venous blood was 96.7% (r =0.946,P <0.001, Kappa value: 0.905). Conclusions The micro-plate RBA of GAD-Ab has high sensitivity, specificity and reproducibility, and can be measured with finger tip blood sampling. It might be a better alternative for clinical practice.

Objective Insulin autoantibody (IAA) is known to exist in sera of type 1 diabetes mellitus (T1DM) patients and pre-T1DM individuals. The aim of this study was to establish a novel microtiter plate radioimmunoassay (RIA) for IAA and evaluate its clinical value. Methods Diluted 125Ⅰ-insulin was mixed with 5 ul serum samples in a 96-well microtiter plate and then incubated for 72 h on an orbital plate shaker (4℃). The immunocomplexes were transferred to another protein a coated Millipore plate, and then the plate was washed with Tri-Buffered Saline Tween-20 (TBT) buffer. Counts per minute (CPM) was measured with liquid scintillation and luminescence counter. The positive cut-off point of IAA index was defined as ≥0.06 based on the 99-percentile of the distribution in 317 healthy individuals. The specificity and sensitivity of the assay were calculated from the samples provided by the fourth Diabetes Autoantibodies Standardization Program (DASP 2005). The IAA levels were determined in 71 T1 DM and 551 newly diagnosed type 2 diabetes (T2DM) patients, and 317 healthy controls. The t test, non-parametric test, x2 test and linear correlation analysis were performed on the data using SPSS 11.5 software. The concordance rate was estimated with Kappa value. Results (1) The optimized testing condition was described as 2×104 CPM of 125Ⅰ-insulin, 5 ul serum sample and slowly horizontal shaking for 72 h. (2) The intra-assay CV was 4.8%-8.9% and inter-assay CV was 6.4%-10.5%. Based on DASP 2005 samples, the specificity and sensitivity of the assay were 97% (97/100) and 50% (25/50), respectively. Ninety-six serum samples with different IAA levels were selected and tested to compare between our new method and a domestic IAA RIA kit. The results showed that the IAA indices from the two methods were positively correlated (r= 0.678, P<0.001). The concordance rate was 72.9 %(Kappa value=0.402). There were 25 samples with discordant results, which were positive for IAA titer using the corresponding microtiter plate RIA but negative using the novel RIA kit. (3) In TIDM group the positive rate of IAA was 19.7% (16/71), higher than the healthy controls (0.9%, x2=54.36, P<0.001). The subgroup of T1DM children (with 0-9 years) showed the highest IAA positive rate (55.6% ,x2=4.85, P<0.05). In T2DM group the frequency of IAA was 1.5% (8/551), which had no significant difference comparing with that of healthy controls (x2= 0.95, P >0.05). Conclusions Our proposed microtiter plate RIA method for IAA is highly sensitive and specific, likely to be feasible for clinical application. The frequency of IAA is high in children with T1DM.

The fast development of the molecular biology and the further research on the nucleic acid set a solid foundation for the development of genosensor.Genosensor is the result of combining molecular biology with microelectronics,electrochemistry,optics and etc,which will build a bridge between the life science and the information science and become one of the most important technologies for DNA information analysis and detection.The working principle,classification of genosenor and the recent research on its application in the detection of functional genes of environmental microorganisms are discussed according to the latest literature.And it is pointed out that the application in the determination of microorganism functional genes in compost is an important development orientation of genosensor.

Objective To establish a three- dimensional hindlimb gait data toolkit (THGT) for healthy and spinal cord injured (SCI) non-human primate (rhesus monkey) based on Matlab to realize upload of original data, automatic gait division, calculation and drawing of multiple gait parameters, etc. Methods Vicon system was used to collect three-dimensional hindlimb gait data of healthy and SCI (after 6 weeks) rhesus monkey to obtain the kinematics data of both hindlimbs in continuous strides. It was analyzed with THGT to process the gait division, calculation and drawing of multiple gait parameters. Results THGT read the data, distinguished cycles of gait, calculated 140 kinds of gait parameters and drew graphs of the results. Conclusion THGT extends the universality of the Vicon data, realizes automatically gait division and friendly interactive interface, and puts out the visible results.

OBJECTIVETo identify the mutations of the tyrosinase gene (TYR) and P gene in patients with oculocutaneous albinism (OCA).

METHODSPolymerase chain reaction (PCR) and denaturing high performance liquid chromatography (DHPLC) were applied to detect the mutations in all exons of TYR gene and P gene. Then DNA sequencing and restriction endonuclease analysis were used to confirm the mutations detected by DHPLC. Novel mutations were screened in 100 unrelated persons with normal phenotypes to exclude the possibility of polymorphism.

RESULTSTwo mutations were detected in the P gene of the three patients and none in TYR gene. Heterozygous mutation of T450M in exon 13 of the P gene was detected in patient 1. Patient 2 had a heterozygous mutation of T450M in exon 13 and a heterozygous mutation of G775R in exon 23 of the P gene. Patient 3 had a heterozygous mutation of G775R as well. Restriction endonuclease analysis of the P gene exon 13 showed that the Oli I site had partly disappeared resulting from the heterozygous mutation T450M in patient 1 and patient 2, but not in 100 unrelated individuals. The heterozygous mutation T450M is a novel mutation.

CONCLUSIONGene diagnosis of OCA can be carried out effectively by combining PCR, DHPLC, DNA sequencing and restriction endonuclease analysis.

Albinism, Oculocutaneous ; genetics ; Base Sequence ; Catechol Oxidase ; genetics ; Child, Preschool ; DNA Mutational Analysis ; Exons ; genetics ; Female ; Hermanski-Pudlak Syndrome ; genetics ; Humans ; Monophenol Monooxygenase ; genetics ; Mutation ; Young Adult

OBJECTIVE: To determine the effect of compound Rhizoma Smilacinus granules (CRSG) on the expression of Bcl-2 and Bax gene in A549 cell lines, and to explore the mechanism of CRSG on non-small cell lung cancers. METHODS: The SD rats were randomly divided into 2 groups: one was administrated with CRSG (n=15), and the other with the same dose of distilled water (n=15). The herbage-containing serum was obtained 2 hours after the 6th treatment. non-small lung cancer A549 cell lines were randomly divided into CRSG group, diamminedichloroplatinum (DDP) group and normal control group, which were cultivated with 10% herbage-containing serum, DDP (3g/mL), and 10% SD rats serum respectively. The cultivated cells were collected after 48 hours, and then RT-PCR technique was used to determine the expression of Bcl-2 and Bax mRNA. RESULTS: Compared with the normal control group after 48 h, the level of Bcl-2 mRNA and the rate of Bc-2/Bax decreased in the CRSG group and the DDP group, and the level of Bax mRNA increased with significant difference (P<0.01). CONCLUSION non-small cell lung cancer A549 cell lines have a high level of Bcl-2 mRNA and a low level of Bax mRNA. CRSG can significantly down-regulate the expression of Bcl-2 mRNA and the rate of Bc-2/Bax, and obviously up-regulate the expression of Bax mRNA, which probably is one of the molecular mechanisms of CRSG in inhibiting the growth of non-small cell lung cancers.
Animals ; Antineoplastic Agents, Phytogenic ; pharmacology ; Carcinoma, Non-Small-Cell Lung ; genetics ; pathology ; Drugs, Chinese Herbal ; pharmacology ; Gene Expression Regulation, Neoplastic ; drug effects ; Lung Neoplasms ; genetics ; pathology ; Male ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction ; Serum ; bcl-2-Associated X Protein ; genetics

BACKGROUNDHuman embryonic stem (HES) cell derived from human blastocyst can be propagated indefinitely in the primitive undifferentiated state while remaining pluripotent. It has exciting potential in human developmental biology, drug discovery, and transplantation medicine. But there are insufficient HES cell lines for further study.

METHODSThree oocyte donors were studied, and 3 in vitro fertilization (IVF) cycles were carried out to get blastocysts for the establishment of HES cell line. Isolated from blastocysts immunosurgically, inner cell mass (ICM) was cultured and propagated on mouse embryonic fibroblasts (MEFs). Once established, morphology, cell surface markers, karyotype and differentiating ability of the cell line were thoroughly analyzed.

RESULTSFour ICMs from 7 blastocysts were cultured on MEFs. After culture, one cell line (cHES-1) was established and met the criteria for defining human pluripotent stem cells including a series of markers used to identify pluripotent stem cells, morphological similarity to primate embryonic stem cells and HES reported else where. Normal and stable karyotype maintained over 60 passages, and demonstrated ability to differentiate into a wide variety of cell types.

CONCLUSIONSHES cell lines can be established from gamete donors at a relatively highly efficient rate. The establishment will exert a widespread impact on biomedical research.

Blastocyst ; cytology ; Cell Differentiation ; Cell Line ; DNA-Binding Proteins ; analysis ; Female ; Fertilization in Vitro ; Humans ; Karyotyping ; Male ; Octamer Transcription Factor-3 ; Stem Cells ; cytology ; Tissue Donors ; Transcription Factors ; analysis

BACKGROUNDThe efficiency of traditional cryopreservation of human embryonic stem (ES) cells is low, and there have been few attempts to prove new cryopreservation methods effective. This study was designed to evaluate the efficiency of cryopreservation of human ES cells using vitrification method.

METHODSHuman ES cells clumped from an identical cell line were randomly allocated to be cryopreserved by vitrification or by slow freezing. The recovery rates, the growth and differentiation potential of thawed human ES cells were compared between these two groups. The pluripotency of human ES cells after thawing was identified.

RESULTSEighty-one point nine percent (59/72) of human ES cell clumps were recovered after vitrification, while only 22.8% (16/70) were recovered after slow freezing (P < 0.01). The colonies after vitrification manifested have not only faster growth but also a lower level of differentiation when compared to colonies subjected to the slow freezing protocol. However, the rates of growth and differentiation in undifferentiated colonies from both groups were identical to the rates in those of non-cryopreserved stem cells after a prolonged culture period. Passage 6 of vitrified human ES cells retained the properties of pluripotent cells, a normal karyotype and expressed the transcription factor OCT-4, stage specific expressed antigen-4 (SSEA-4) and SSEA-3. Teratoma growth of these cells demonstrated the ability to develop into all three germ layers.

CONCLUSIONSVitrification is effective in cryopreserving human ES cells. During a prolonged culture, human ES cells retain their pluripotency after cryopreservation.

Cell Differentiation ; Cell Survival ; Cryopreservation ; methods ; Embryo, Mammalian ; cytology ; Humans ; Osmotic Pressure ; Stem Cells ; cytology

Objective Diminished ovarian reserve (DOR) severely affects the life of women and the estrogen replacement therapy for it has obvious adverse effects. This article aimed to study the effect of polygoni multiflori radix preparata (PMRP) on DOR in rats and provide a therapeutic option for clinical medication. Methods Sixty female SD rats were randomly divided into six groups of equal number,normal control,DOR model control,high-dose PMRP (4 g/kg),medium-dose PMRP (2 g/kg),low-dose PMRP (1 g/kg),and positive control. The DOR model was established by gavage of tripterygium glycosides as 75 mg/kg every morning,followed by administration of PMRP in the PMRP groups,Estradiol valerate at 0.18 mg/kg in the positive control group and distilled water in the model control group in the afternoon,all for 30 consecutive days. The estrous cycle of the rats was observed,the levels of serum estradiol (E2),follicle-stimulating hormone (FSH),luteinizing hor-mone (LH),anti-Müllerian hormone (AMH) and inhibin-B (INH- B) were determined by ELISA,the ovarian and uterine indexes were obtained,and the ovarian morphology was observed by HE stai-ning,and the counts of follicles at different stages were recorded. Results Compared with the normal controls,the DOR model rats showed modeling time-related lengthening,irregularity and even disorder of the estrous cycle,with a few epithelial cells or keratino-cytes and leucocytes on the vaginal smear at 11-30 days. The estrous cycle was normal in the PMRP and positive control groups at 1-10 days and relatively prolonged at 11-30 days. In comparison with the normal control group,the DOR model rats exhibited a signifi-cantly decreased levels of serum E2 ([302.6±42.9] vs [155.7±46.8] pg/mL,P<0.05) and INH-B ([494.5±84.1] vs [299.2± 106.8] pg/mL,P<0.05) but increased levels of FSH ([7.2±0.5] vs [21.7±1.2] mIU/mL,P<0.05) and LH ([17.4±1.2] vs [25.0±1.0] mU/mL,P<0.05). The INH-B level was markedly elevated in the PMRP and positive control groups as compared with that in the DOR models (P<0.05). The counts of follicles and corpora lutea were remarkably lower in the DOR model rats (P<0.05) while that of developing follicles markedly higher in the PMRP and positive control groups than in the normal control group (P<0.05). The numbers of atretic follicles+corpora lutea were significantly increased in the high-dose PMRP group but decreased in the low-dose PMRP group (P<0.05) and positive controls (P<0.05). The counts of primordial and developing follicles were dramatically higher in the PMRP and positive control groups than in the DOR model controls (P<0.01) and so were the numbers of atretic follicles+corpora lutea in the high-and medium-dose PMRP groups (P<0.05). Conclusion Polygoni multiflori radix preparata can effectively protect the reproductive function of female rats by inhibiting tripterygium glycosides-induced toxicity to the ovary.