Objective To prepare high-quality refined and depolymerized capsular polysaccharide(CPS) of Streptococcus pneumoniae for preparation of polysaccharide vaccine and polysaccharide conjugate vaccine against Streptococcus pneumoniae.Methods Refined CPS of type 6A was prepared by acid precipitation method from the inactivated fermentation broth of type 6A Streptococcus pneumoniae,and the final concentration of CaCl_2(80,160,240,320 mmol/L) and pH(2.5,3.0,3.5,4.0) were optimized.Three batches of type 6A refined CPSs were prepared by the optimized method,and the applicability of the method to polysaccharides of 5,7F,10A and 19F types was verified.After removing impurities from the inactivated broth of type 6 A Streptococcus pneumoniae by acid precipitation,the type 6 A depolymerized CPS was prepared by trifluoroacetic acid method,and the reaction temperature(8,25 and 40℃),the final concentration of trifluoroacetic acid(0.25,0.50,1.00 mol/L) and the reaction time(1,3,6 h) were optimized.Three batches of depolymerized CPSs were prepared by the optimized method,and compared with the high-pressure homogenization method,and then the applicability of trifluoroacetic acid method to depolymerized CPSs of 5,10A and 19F types was verified.The quality of refined and depolymerized CPSs was tested according to the methods specified in Chinese Pharmacopoeia(Vol Ⅲ,2020 edition).Results The optimum final concentration of CaCl_2 and pH of acid precipitation method were 160 mmol/L and 3.0 respectively.The prepared type 6A,5,7F,10A and 19F refined CPSs were all qualified.The optimum reaction temperature,reaction time and final concentration of trifluoroacetic acid were 25℃,3 h and 0.50 mol/L for trifluoroacetic acid method.The prepared type 6A,5,10A and 19F depolymerized CPSs were all qualified.Conclusion The refined and depolymerized CPSs of Streptococcus pneumoniae prepared in this study meet the requirements of Chinese Pharmacopoeia(Vol Ⅲ,2020 edition),and the preparation process is suitable for the preparation of various types of polysaccharides.

The increase of blood-brain barrier (BBB) permeability is a key link in causing the pathological changes in vasogenic brain edema and inflammatory reaction. In recent years, a number of studies have indicaded that a lot of mediators participated in the structural and functional changes and damage of BBB during the process of cerebral ischemia-reperfusion.

There exists different view in the goal of investigative study.Based on the self-fulfilling cycles of self-regulated learning,the author of the article puts forward that developing the ability of self-regulated learning by doing investigative study according to each phase characteristic of self-regulated learning is one of the important goals of investigative study.

C.Conclusion: The drug releasing rate of Icariin Ointment made of emulsion ointment base is the fastest.

ObjectiveTo study the characteristics of nonfunctioning parathyroid cysts (NFPTC) for its diagnosis and treatment.Methods 5 cases of NFPTC were hospitalized during 1985～1999. The clinical features, serum calcium evaluation ultrasonography and nuclide scanning were performed. Postoperative pathologic and immunihistochemistry detection in NFPTC were made.ResultsTumours in the 5 cases were removed by operation and diagnosis was verified by pathology. Tumors were all positive for chromogranin A (CgA),synaptophysin(Syn),and neuron specific enolase(NSE). Follow up found no recurrence. ConclusionsSurgical resection is most effective in treating NFPTC and diagnosis is made by pathologic examination.

Objective To study the effect of c-myc small interference RNA(siRNA) on c-mye protein in leukemic cells, and investigate a new method of gene therapy on leukemia. Methods siRNA against c-myc mRNA were designed and synthesized. The siRNA at 100 nmol/ml density was transfected into HL-60 cells. The cells cultured at 24 h, 48 h or 72 h were collected after being transfected, and the total protein of the cells was extracted according to the instruction booklet of TRIzol reagent. The expression level of c-myc protein was examined by Western blotting. Results After being treated with siRNA of c-myc, the quantity of c-myc protein was obviously reduced. It was remarkably lower than that of the control group. Furthermore after 72 h treatment with siRNA, the expression of c-myc protein reached its lowest. Conclusion The siRNA of c-myc can suppress the expression of c-myc protein in HL-60 cells. There are sequence targeted and time-dependence effect. The siRNA of c-myc may become a new tool of gene therapy on leukemia.

Objective To study the effect of methyl mercury on the development of rat offspring. Methods The male Wistar rats were divided into four groups randomly, each group was administrated methyl mercury by gavage every two days for two months, then, the rats were mated with healthy female rats. The development, growth and behaviors of offspring were investigated. Results Compared with the control, the body weights of offspring in groups of 1.170 mg/kg and 0.580 mg/kg were less and the development was tardy. The indexes that can reflect the level of development showed that the behaviors of offspring in experimental groups were damaged. Conclusion The male rats exposed to methyl mercury may produce an adverse effect on the development, growth and behaviors of their offspring.

Objective To investigate the expression of C-erbB-2 and anti-nuclear antigen Ki-67 in thyroid tumor, and its significance in pathologic diagnosis and prognosis the patient. Methods SP immunohistochemical technique was used to detect the expression of C-erbB-2 and Ki-67 in thyroid tissue of 90 cases of thyroid carcinoma and 20 cases of thyroid adenoma. Results High expression of both C-erbB-2 and Ki-67 in thyroid carcinoma, and their expression was weak in thyroid adenoma. The positive rate of C-erbB-2 expression in thyroid carcinoma was statistically higher than that in thyroid adenoma (48.9% vs 20.0%, P

Objective To study the tooth whitening effect of boron-dipyrromethene (BODIPY) as a photosensitive drug combining photodynamic therapy (PDT) and the influence on the surface of the enamel.Methods After oxidation of hydrogen peroxide or BODIPY by photodynamic therapy,the extracted teeth were evaluated by Vita shade guides matching.The change of surface enamel on the crystals and microstructure was observed by scanning electron microscopy (SEM).Results The teeth treated with BODIPY by PDT were smooth and whitened with the remineralization of teeth surface in morphology.While the teeth treated with hydrogen peroxide were whitened obviously but the surface morphology of the teeth was demineralized seriously.Conclusion The results suggest that PDT is effective for teeth whitening and can promote the remineralization of teeth surface enamel with BODIPY as a photosensitive drug.PDT is expected to become a new method for tooth whitening.

Objective To explore the changes in serum leptin level in the elderly patients with chronic heart failure(CHF) and the relatonship between leptin and blood-pressure. Methods Serum leptin levels were studied in 35 male patients with CHF and 30 male normal controls.The relationship of serum leptin with blood pressure and LVEF were analyzed. Results Compared with controls,patients with CHF had higher serum leptin,syst olic blood pressure(SBP)and cliastolic blood pressure(DBP)(P