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 To investigate the relationship between spontaneous miscarriage and embryonic chromosome abnormalities,and to evaluate the clinical application of karyotype analysis by chorionic villus cell culture. Methods The chorionic villus karyotype of 1983 cases of miscarriage from January 2010 to July 2016 in Guangzhou Women and Children′ s Mecical Center were analyzed retrospectively. The miscarried chorionic villi were obtained by curettage under sterilized condition. The chromosome specimens were prepared after chorionic villus cell culture. Karyotype analysis was performed by G-banding technique. Results In the 1983 samples, successful karyotype analysis was performed in 1770 cases, with the successful rate of 89.98%. Chromosomal abnormalities were found in 1038 cases (58.64%,1038/1770). Chromosomal structural abnormalities were found in 37 cases. The numeral abnormalities were more common than structural abnormalities, and most of the numeral abnormalities were aneupoidies. In turn, they were trisomy 16, 45,X, trisomy 22, trisomy 2, trisomy 21, trisomy 15. The most common structural abnormality was balanced translocation, including Robersonian translocation. Female embryoes accounted for 61.02%(1080/1770) miscarriages and for 57.4%(596/1770) of chromosomal abnormalities, while male embroyes acoounted for 61.02%(1080/1770),57.4%(596/1770)respectively. The proportion of female embryoes was higher than male embryoes. The median age of the patients was 30 years old(16-46 years old). As the maternal age increased, the proportion chromosomal abnormalities increased. The incidence of chromosomal abnormalities in the advanced age group (≥35 years) was 68.38%(240/351), which was significantly higher than that in the younger group (56.24% ,798/1419; χ2=17.10, P<0.01). Conclusions Embryonic chromosomal abnormalities are the most common cause of early spontaneous miscarriage. The abnormalities centralize in some karyotypes. There is certain relationship between maternal age and the incidence of miscarriage, as well as the embryonic gender. Chorionic villus cell culture and karyotype analysis are helpful in finding the cause of miscarriage and counsel the patients.

Objective To compare the curative effect of nasal intermittent positive pressure ventilation (nIPPV ) and nasal con-tinuous positive airway pressure (nCPAP) method .Methods Retrospective study was took on 196 neonatal infants ,all cases were assigned into nIPPV group (n=102) and nCPAP group (n=94) according to mode of ventilation from January 2011 to December 2012 in a neonatal intensive care unit of this hospital .The ratio of requirement for endotracheal ventilation and the outcome were in-vestigated .Results Infants treated initially with nIPPV need less endotracheal ventilation and ventilation time than those treated with nCPAP (11 .8% vs .24 .5% ,P<0 .05) .Conclusion Compared with nCPAP ,nIPPV decreased the requirement for endotrache-al ventilation in neonatal infants after extubation .

Objective To determine the value of spectral karyotyping(SKY)in identification of the marker chromosome.Methods Selected six cases that could not be identified in clinic were studied,using samples of peripheral blood from four cases,and samples of amonic fluid and fetal cord blood for prenatal diagnosis in two cases were investigated.All cases were analyzed with the routine SKY method.and the results with the SKY View software.The SKY results were identified by using fluorescence in situ hybridization(FISH).And C-banding technique was used to help diagnose the heterochromatin.Results SKY wag successfully performed on all of 6 cases.The origin of all marker chromosomes was identified by SKY.Except case No.4,the others were confirmed by FISH.It helped determine the pregnancy outcome in two cases of prenatal diagnosis:one case of genetic marker chromosome continued the pregnancy,and another case of de novo marker chromosome was terminated of the pregnancy.Conclusion SKY may be a vahable tool to diagnose the marker chromosome with rapidness,direct-viewing and sensitiveness.It can be used to assess the prognosis and the pregnancy outcome.

Objective To explore the status quo and the correlation of professional practice environment and job burnout in head nurses. Methods Totally 646 head nurses from city state hospitals of Hunan Province was selected by cluster sampling method. Participants were investigated by using the Chinese Version of Profession Practice Environment Scale for Head Nurses and Maslach Burnout Inventory. Results The professional environment score was 215.95±22.81, which was in the moderate level. The score of emotional exhaustion (EE) in head nurses was 24.56 ± 10.64, depersonalization (DP) was 8.92 ± 4.17 and personal accomplishment (PA) was 35.55±13.08, all stating moderate burnout. Meanwhile, the scores of EE and DP were negatively correlated with professional practice environment (r=-0.350--0.161, P≤0.01), while the PA was positively correlated with professional practice environment (r=0.078- 0.271, P≤0.01). Conclusions Professional practice environment in head nurses is correlated with job burnout. Hospital leaders should pay more attention to head nurses′professional practice environment to decrease job burnout in head nurses.

Objective To investigate the clinical value of evaluation of fetal cardiac function in congenital heart disease by brain natriuretic peptide (BNP) and velocity vector imaging (VVI). Methods Fetuses who came from Shenzhen Maternity & Child healthcare Hospital were divided into the congenital heart disease group and the control group. At the same time we collected amniotic fluid and assayed BNP concentration. Using the VVI software, the velocity, strain and strain rate of the global and segmental of the left ventricle were measured. Comparison and correlation were made between the two groups. Results There was significantly difference of BNP concentrations in amniotic fluid between two groups. The gestational age had significant positive correlation with BNP concentrations in disease group. The comparison of global velocity, strain and strain rate of left ventricle between the two groups showed significant differences. All of the left ventricular dynamic parameters in disease group were lower than those of the control group. Conclusions Compared with the control group, the disease group had a high level of BNP in amniotic fluid and a lower level of dynamic parameters of left ventricular. There was a positive correlation between BNP concentration and gestational age in disease group. So we can conclude that theBNP concentration can be a biological parameter for evaluating the latent impairments of fetal cardiac function.

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 investigate the risk factors for hypoglycemia after birth in preterm infants with a gestational age of ≤32 weeks. METHODS: A retrospective analysis was performed for 86 neonates with hypoglycemia and a gestational age of ≤32 weeks who were admitted to the neonatal intensive care unit from January 2017 to June 2020 (hypoglycemia group). A total of 172 preterm infants with normal blood glucose who were hospitalized during the same period were randomly enrolled as the control group. Univariate analysis and multivariate logistic regression analysis were used to screen out the risk factors for hypoglycemia in preterm infants. RESULTS: There were 515 preterm infants during the study, among whom 86 (16.7%) had hypoglycemia. Compared with the control group, the hypoglycemia group had significantly higher percentages of small for gestational age (SGA), cesarean section, maternal hypertension, and antenatal steroid administration (P<0.05), but significantly lower birth weight and rate of intravenous glucose use before blood glucose test (P<0.05). SGA (OR=4.311, 95%CI: 1.285-14.462, P<0.05), maternal hypertension (OR=2.469, 95%CI: 1.310-4.652, P<0.05), and antenatal steroid administration (OR=6.337, 95%CI: 1.430-28.095, P<0.05) were risk factors for hypoglycemia in preterm infants, while intravenous glucose use (OR=0.318, 95%CI: 0.171-0.591, P<0.05) was a protective factor against hypoglycemia in preterm infants. CONCLUSIONS SGA, maternal hypertension, and antenatal steroid administration may increase the risk of early hypoglycemia in preterm infants with a gestational age of ≤32 weeks, and intravenous glucose use is recommended as soon as possible after birth for preterm infants with a gestational age of ≤32 weeks to reduce the incidence rate of hypoglycemia.
Cesarean Section ; Female ; Gestational Age ; Humans ; Hypoglycemia/etiology* ; Infant ; Infant, Newborn ; Infant, Premature ; Infant, Small for Gestational Age ; Pregnancy ; Retrospective Studies ; Risk Factors

The purpose of this investigation is to improve ethanol production and decrease acetate formation in Saccharomyces cerevisiae strain YS2-?adh2.The strain YS2-?adh2 with deleted alcohol dehydrogenase Ⅱ(adh2) gene was isolated in our lab with higher ethanol production than that of the strain YS2.The ace-taldehyde dehydrogenase Ⅵ(ald6) gene encoded a cytosolic acetaldehyde dehydrogenase,a key enzyme of the pyruvate dehydrogenase(PDH) bypass,transfers acetaldehyde to acetate.To disrupt ald6 gene of the strain YS2-?adh2,ald6 gene targeting cassettes were synthesized by long flanking homology PCR(LFH-PCR) and then were transformed into YS2-?adh2 mutants by LiAc/SS Carrier DNA/PEG method.Positive transformants were selected with G418 and further confirmed by PCR.Once correctly integrated into the genome,the selective marker was rescued by transforming the plasmid pSH65 into the positive transformants and inducing the Cre expression with a Cre/loxP-mediated marker removal procedure.We named the ald6 gene knocked-out strain as YS2-?adh2-?ald6 which has a 12.5% higher ethanol production and a 18% lower acetate formation compared to the strain YS2.

OBJECTIVETo explore the effect of combined preoperative chemotherapy with radiotherapy on locally advanced lower rectal carcinoma.

METHODSThirty- five patients with locally advanced lower rectal carcinoma were received a new regimen of combined preoperative chemotherapy with radiotherapy. Routine fr action of radiation was given with total dose of 46 Gy,2 Gy per fraction,five ti mes a week. Patients received oxaliplatin 130 mg/m(2) (infusion) on day 1, plus leu novorin 200 mg/m(2) and 5- FU 500 mg/m(2)(intravenous bolus) from day 1 to day 3 eve ry 3 weeks for total two cycles before irradiation. Operation was performed 4 to 6 weeks later after neoadjuvant therapy.

RESULTSAfter neoadjuvant therapy,all patients underwent surgical resection with complete pathologic response in 7 patients,average tumor size decrease of in 34.4%, tumor stage decrease in 65.7% o f patients and nodal- negative change rate of 55.6%. Radical resection was per formed in 34 patients,in whom 18 patients received abdominoperineal resection(AP R) and 16 patients received sphincter- preserving surgery with 45.7% of anal preservation rate. One patient received palliative resection. No local recurrence occurred in all patients who received radical resection,but two cases had liver metastasis.

CONCLUSIONCombined preoperative chemotherapy with radiotherapy is a better neoadjuvant therapy for lower advanced rectal cancer,which can decrease tumor stage,improve resectability and anal sphincter preservation rate,therefore ,this new neoadjuvant therapy with tolerable toxicity will has a promising application in the clinical setting.

Adult ; Aged ; Chemotherapy, Adjuvant ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Neoadjuvant Therapy ; Neoplasm Staging ; Radiotherapy, Adjuvant ; Rectal Neoplasms ; pathology ; surgery ; therapy ; Treatment Outcome