E.coli single-stranded DNA-binding protein (SSB) plays an important role in replication, recombination and repair of DNA and is thus crucial for the survival of the bacteria.We described a high expression and efficient purification scheme and kinetic assay of interaction with its substrate, single-stranded DNA (ssDNA). A ssb gene (537 bp) for encoding SSB was obtained by PCR amplification from E.coli K-12 genome. The expression vector of the fusion protein SSB was constructed by attaching ssb gene to pQE30. SSB fusion protein was expressed in M15 E.coli strain induced by IPTG. SDS-PAGE analysis revealed that the expected protein with a molecular weight 20.6kDa was soluble and amounted to about 30% of the total bacterial protein. SSB protein was purified by immobilized metal (Ni2+) chelation affinity chromatography and the purity was about 90%. The resulting SSB protein was a correctly folded tetramer analyzed by gel filtration. It could bind ssDNA with equilibrium dissociation constant (KD) of 4.79×10-7 mol/L as determined by surface plasmon resonance.

Objective To investigate relationship between obstructive sleep apnea hypoventilation syndrome(OSAHS) and hypertension.Methods Questionnaire survey was conducted among 1573 local permanent residents in Guangzhou during March and June 2006 to understand prevalence of hypertension and snoring,and polysomnography monitoring was performed for 347 of them with moderate and severe snoring to estimate prevalence of OSAHS.Risk factors for hypertension was screened with multivariate logistic regression analysis.Results In total,1547 copies of valid questionnaires were collected,and 184 cases (11.9%) of hypertension were found with a prevalence of 10Department of Endocrinology,Shanxi Provincial People's Hospital,Taiyuan 030012,China 0%,49 of diabetes with a prevalence of 2.7%,and 212 of dyslipidemia with a prevalence of 10.4%.Prevalence of OSAHS was found in 34 of them (2.2% ) with Epworth sleepiness scale (ESS) score equal to or greater than nine.Prevalence of hypertension in OSAHS group was 32.5%,much higher than that in non-snoring group (8.3% ) and snoring group ( 17.1% ).Results of logistic regression analysis showed that age,gender,OSAHS,diabetes and dyslipidemia all were high-risk factors for hypertension,with OSAHS ranking the third.Conclusion OSAHS is one of high-risk factors for hypertension.

0.05). CONCLUSION Obesity was an influential factor of snoring. The PS and OSAHS have the same effect on children growth and their clinical features.

0.05),but there was a significant difference in the lowest SaO2,average SaO2 and AHI between the 2 groups(P

OBJECTIVE To summarize the clinical experience of endoscopic thyroidectomy via suprasternal approach. METHODS Endoscopic thyroidectomy via suprasternal approach was performed in 35 patients with ultrasonic scalpel. RESULTS Operations were successfully performed in 35 patients. The mean operation times were 130 (105～190) minutes in 24 cases with subtotal lobectomy and 4 case with total lobectomy, 60 (50~70) minutes in 2 cases with isthmectomy, 228 (185～270) minutes in 2 case with bilateral subtotal lobectomy, 163 (140～215) minutes in 3 case with subtotal lobectomy and the contralateral ademona resection. The bleeding during operation was 5 to 40ml and the average hospital stay time was 4 (3～5) days. CONCLUSION Endoscopic thyroidectomy via suprasternal approach is a safe way with good cosmetic value.

Aim To investigate the effects of diterpene ginkgolides meglumine injection (DGMI ) on amino acids and monoamine neurotransmitters in rats with cerebral ischemia/reperfusion injury.Methods In-traluminal suture was applied to establish middle cere-bral artery occlusion (MCAO/R)model with ischemia for 1.5 h and reperfusion for 24 h.After the adminis-tration of DGMI (i.v.),the levels of amino acid and monoamine neurotransmitters in brain tissue were de-tected through HPLC-ECD.Results DGMI down-reg-ulated the concentrations of aspartic acid, glutamic acid,glycine and γ-aminobutyric acid which were in-creased in MCAO/R group.DGMI also reduced the levels of norepinephrine epinephrine,glyoxylic acid, serotonin and 5-HIAA in cortex and hippocampus,and increased adrenaline content compared to the model group.Conclusion DGMI exhibits a protective role in rats with cerebral ischemia /reperfusion injury through regulating amino acids and monoamine neuro-transmitters.

OBJECTIVE: To analyze the conservative management and outcomes of pharyngocutaneous fistula after total laryngectomy. METHOD: Twenty-one patients with postoperative fistulas were identified and treated by conservative therapy. RESULT: Different treatment were given basing on the three stages of pharyngocutaneous fistula: drainage and cleaning stage, pressure bandaging stage and healing stage. Fourteen patients (66.7%) with the conservative therapy resumed oral feeding after closure of fistula, the other 7 patients had to be cured by further operation. CONCLUSION Management basing on the stages of pharyngocutaneous fistula can achieve satisfied outcome. It can provide important information for pharyngocutaneous fistula's treatment.
Carcinoma, Squamous Cell ; surgery ; Cutaneous Fistula ; therapy ; Humans ; Laryngeal Neoplasms ; surgery ; Laryngectomy ; adverse effects ; Pharyngeal Diseases ; therapy ; Postoperative Complications ; therapy

OBJECTIVE: To investigate the features and diagnosis way of small round cell tumor of nasal sinus and bases of skull. METHOD: A retrospective analysis of 123 case with small round cell tumor of nasal sinus and bases of skull were carried out in our hospital in past ten year. Clinical, histological, radiological and immunohistochemical characters of these cases were studied. RESULT: All cases usually complained of nasal obstruction, headache, diplopia, nasal mucus with bleeding, vision or weight loss. Expansible or infiltrative lumps were found in nasal sinus or bases of skull in radiological examination. A lot of small round cells were found in these tumors in histological pathology. At least 5-6 cell, tissue or tumor markers were examined immunohistochemically in most of cases before the final diagnosis were made. In some cases over 20 markers were examined. Five cases were carried out transmission electron microscope examination, special features such as desmosome and myofilament were found. CONCLUSION Clinical symptom, physical signs and radiological finding can supply malignant evidences of these tumors. Histological examination can make certain that they are small round cell tumors, but final diagnosis is still hard to make only by these. Immunohistochemical examination of various markers can tell the original characters of the specimen tissues, it is the key for final diagnosis. Transmission electron microscope examination is another helpful way for diagnosis.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Leukemia, Lymphocytic, Chronic, B-Cell ; diagnosis ; pathology ; Male ; Middle Aged ; Paranasal Sinus Neoplasms ; diagnosis ; pathology ; Retrospective Studies ; Skull Base Neoplasms ; diagnosis ; pathology ; Young Adult

Box-Behnken design-response surface methodology was used to optimize the transformation from chlorogenic acid to neochlorogenic acid.Based on single factor experiments,the experiment design were developed by box-benhnhen central composite design with causal factors of the reaction temperature,time and PH to neochlorogenic acid.The optimum transformation conditions were as follow:reaction temperature at 107℃,reaction time of 60 min,the PH of 4.72.Under the optimum extraction technology conditions,the productivity of neochlorogenic acid was 64.20％.Neochlorogenic acid was isolated and purified.The determination and characterization of neochlorogenic acid was detected by HPLC,1H-NMR,13C-NMR and ESI-MS.The results showed that the content of neochlorogenic acid reached to 98.78％ and the yield of 87.37％.