Aim To study the fluorescence spectroscopy of human serum albumin(HSA)and the interaction of aspirin and HSA.Methods The quenching mechanism of the fluorescence of human serum albumin by aspirin was studied with the fluorescence.The interaction dissociation constants KD of human serum albumin and aspirin were determined at different temperatures according to double reciprocal Lineweaver-Burk plot and the main binding force was discussed by thermodynamic equations.The effect of aspirin on human serum albumin was also studied by synchronous fluorescence spectrometry.Results The quenching mechanism of aspirin to human serum albumin was static quenching.The interaction dissociation constants KD at 37℃,25℃ was 1.44?10-3 and 1.96?10-3 mol?L-1 respectively.The thermodynamic parameters of the reaction was-19.73 kJ?mol-1(?H),-16.21 kJ?mol-1(?G),-11.77 kJ?mol-1(?S).Conclusions The main binding force between aspirin and HSA was Van der Waals interaction.Aspirin binding on the human serum albumin could change the serum protein conformation.

Objective To study the mechanics situation of proximal femoral locking plate internal fixation after dynamic hip fixation in-tertrochanteric fracture. Methods Totally 10 couple of elderly proximal femur specimens were collected and intertrochanteric fracture model were prepared. Fixation material was removed after dynamic hip screw fixation. The left sides were collected as control group and given anti-rotation intramedullary nail internal fixation, while the right side were collected as observation group and given proximal femoral locking plate internal fixation. Then vertical displacement, axial stiffness and rotational stiffness under different loads were compared. Results Under dif-ferent loads, femoral bone vertical displacement and femur tuberosity vertical displacement in the observation group were both significantly shorter than those in the control group (P<0. 05), and femoral bone and femur tuberosity axial stiffness and rotational stiffness in the observation group were significantly higher than those of the control group (P<0. 05). Conclusion Proximal femoral locking plate internal fixation can improve stress load and enhance axial stiffness and rotational stiffness, and it's an ideal material for refracture fixation model after dynamic hip fixation intertrochanteric fracture.

Aim To compare the interactions of baicalein and baicalin with bovine serum albumin (BSA) and their mechanism. Methods The binding reactions of baicalein and baicalin with BSA and the effects of glucose on them were studied by spectroscopy to compare the binding constants and binding distances of baicalein-BSA and baicalin-BSA,which were calculated according to Lineweaver-Burk equation and F?ster' energy transfer theory. Thermodynamic parameters were used to calculate the types of interaction force between BSA with baicalein or baicalin and the technique of synchronous fluorescence spectra was used to observe the effects of baicalein or baicalin on the conformation of BSA. Results Both the binding constants and binding distances of baicalein-BSA and baicalin-BSA decreased with temperature increasing and were increased by glucose. Relative to baicalein,the binding affinity of baicalin to BSA decreased obviously with an increase in binding distance. Both baicalein and baicalin could form non-covalent compounds with BSA mainly to quench the intrinsic fluorescence of BSA through a static quenching procedure. Baicalein could interact with BSA through hydrogen bonds and Van der Waals force,and baicalin did it mainly through electrostatic force. Though baicalein or baicalin could induce the conformational changes of BSA by binding reaction,only the former reduced the hydrophobicity in microenvironment around the tryptophan moieties of BSA. Conclusions The glycosylation substitution of baicalein molecule can decrease the binding to BSA (baicalin-BSA) and change the types of interaction force. The physiological concentration of glucose increases the binding constants and the number of binding sites of baicalein and baicalin with BSA.

In order to confirm the role that the 49th amino acid residue plays in enzymatic inactivity of Glutamine 49 phospholipase A2(Gln49-PLA2),site-directed mutagenesis of its 49th amino acid gene codon was conducted using PCR.Aspartic acid 49 phospholipase A2(Asp49-PLA2-Q49D-PLA2),the mutant of Gln49-PLA2 was expressed in E.coli with pET32a+ vector.The fusion protein,expressed as inclusion body,after being denatured,was on-column refolded and purified by immobilized metal affinity chromatography(IMAC),and then cleaved by Factor Xa.The mature Q49D-PLA2 mutant was obtained by Hitrap SP cation exchange and Superdex 75 gel filtration chromatography,with the recovery rate of 1.3%,and the specific activity of the mature Q49D-PLA2 mutant was 72 U/mg.It has been demonstrated that the 49th glutamine amino acid residue is the main reason in enzymatic inactivity of Gln49-PLA2 and the results are helpful for denatured protein refolding,especially in rich disulfide bonds conditions.

Objective To construct the murine IL-21 (mIL-21) tumor vaccine modified by glyco-syl phosphafidylinositol(GPI), and to evaluate its anti-tumor effect and mechanisms. Methods The IL-21-GPI gene was acquired by overlap PCR and inserted into PeDNA3.1. The recombinant plnsmid pcDNA3.1/ IL-21-GPI was transformed into cell B16F10, and the expression of mIL-21 on cell membrane was deter-mined by cell indirect immumofluorescence and flow cytometry (FCM). The bioactivity of mIL-21 was iden-tiffed according to its effects on the proliferation of mouse spleen cells. The anti-tumor effect was evaluated depending on the tumor size and the survival of tumor-beating mice after the tumor vaccine was inoculated into C57BL/6 mice. And the activity of cell-mediated immunity in immunized mice was detected at the same time. Results The recombinant plasmid pcDNA3.1/IL-21-GPI was correctly constructed, which could ex-press mIL-21 binding the membrane with good bioactivity. The vaccine had good anti-tumor effect, and the cell-mediated immunity had been improved in immunized mice. Conclusion The GPI modified mIL-21 tumor vaccine with anti-tumor activity was constructed successfully, which provided a good foundation for studying anti-tumor immunity and therapy in future.

This study was to explore the expression of two subtype molecules of CD133 and its relationship with clinical prognostic factors in childhood with B linage acute lymphoblastic leukemia (B-ALL) at initial diagnosis and the 33rd day of induction chemotherapy. Expression of CD133-1 and CD133-2 in 48 cases of B-ALL and 25 cases at initial diagnosis and the 33rd day of treatment was detected by flow cytometry. Minimal residual disease (MRD) of B-ALL at 33rd day was evaluated by flow cytometry. The results indicated that the expression of CD133-1 was positive in 18 cases (37.5%), and expression of CD133-2 in 30 cases (62.5%) was positive from 48 cases with newly diagnosed ALL (P < 0.05). At 33rd day of treatment, expression of CD133-1 in 2 cases (8.0%) from 25 cases was positive, and expression of CD133-2 in 23 cases (92.0%) was positive (P < 0.05). After induction chemotherapy in B-ALL, the expression of CD133-1 decreased significantly, but still higher than that in the normal control group. Compared to expression of CD133-1, expression of CD133-2 decreased slowly. It is concluded that there is no relations among expression of CD133 and sex, age, white blood cell count, percentage of bone marrow blast cells, FAB subtype, cytogenetics, leukemia fusion gene, risk stratification and complete remission rate in childhood B-ALL. The positive expression rates and levels of CD133-2 are higher than those of CD133-1 in B-ALL. There is no statistical correlation between expression of CD133 and CD34 in B-ALL. The expression of CD133-2 is significantly related to the level of MRD.
AC133 Antigen ; Acute Disease ; Adolescent ; Antigens, CD ; immunology ; metabolism ; Child ; Child, Preschool ; Female ; Gene Expression Regulation, Leukemic ; Glycoproteins ; immunology ; metabolism ; Humans ; Infant ; Leukemia, B-Cell ; immunology ; metabolism ; Male ; Neoplasm, Residual ; Peptides ; immunology ; metabolism

Objective To establish an infectious disease field prevention and control equipment system to facilitate equipment efficacy evaluation. Methods The equipment system was determined by analyses on the main procedure of infectious disease field prevention and control,researches on the missions and equipment requirements of grades of facilities for disease prevention and control,references to related equipment allocation standards as well as expert consulting.Results The first-grade system consisted of six classes and 136 subclasses of equipment,the second-grade system was made up of six classes and 114 subclasses of equipment and the third-grade system included six classes and 58 subclasses of equipment. Conclusion The three-grade infectious disease field prevention and control equipment system contributes to equipment efficacy evaluation.

CD22 is a transmembrane sialoglycoprotein and a member of the immunoglobulin superfamily. Its expression is restricted to the B cell lineage and a vast majority of B cell NHLs. CD22 plays a key role in B cell development, survival, and function. Humanized anti-CD22 antibodies were developed to minimize the immunogenicity and to enhance effector interactions during their developments of diagnostic and immunotherapeutic agent. Preclinical test with anti-CD22 antibodies indicates that a single, conjugated or radiolabeled agent has shown preliminary antitumor activity in patients with recurrent and heavily pretreated NHL. Anti-CD22 antibodies were well tolerated, without dose-dependant toxicity. Anti-CD22 antibodies are currently being evaluated in combination with rituximab, and the early results suggest that the combination of the two antibodies are well tolerated and may result in better clinical activity than the single agent alone. Thus, anti-CD22 antibodies are theoretically good candidates alone and in combination with other drugs in the treatment of B cell malignancies. In this review, the physiologic function and characteristics of CD22 antigen as target molecule of guide therapy for NHL, the types of anti-CD22 antibodies in therapy of NHL and the combination use with other antibodies were summarized.
Animals ; Antibodies, Monoclonal ; immunology ; therapeutic use ; Antibodies, Monoclonal, Humanized ; Humans ; Immunotherapy ; Lymphoma, Non-Hodgkin ; therapy ; Sialic Acid Binding Ig-like Lectin 2 ; immunology

The aim of this article is to provide methods for the isolation and identification of pancreatic stem cells and cell source for research and therapy of diabetes. ICCs were isolated by collagenase IV digesting and then cultured; epithelial cells were purified from monolayer cultured ICCs. The growth curve of the epithelial cells was measured by MTT. The expression of molecular markers in the cells was identified by immunohistochemical staining. The surface markers in the epithelial cells were analyzed by FACS. Epithelial cells were purified from isolated human fetal ICCs and passaged 40 times, and 10(6) - 10(8) cells were cryopreservated per passage. The growth curve demonstrated that the epithelial cells proliferated rapidly. The epithelial cells expressed PDX-1, PCNA, CK-7, CK-19, Nestin, Glut2, and Vimentin, but Insulin was undetected. The cells expressed CD29, CD44, and CD166, but did not express CD11a, CD14, CD34, CD45, CD90, CD105, and CD117. Taken together, these results indicate that self-renewable epithelial cells can be isolated and purified from human fetal pancreas. These also show that the epithelial cells originate from ducts and have the characteristics of pancreatic stem cells.
Cell Culture Techniques ; Cell Proliferation ; Cell Separation ; Cell Survival ; Cells, Cultured ; Epithelial Cells ; cytology ; metabolism ; Fetus ; Flow Cytometry ; Homeodomain Proteins ; analysis ; Humans ; Hyaluronan Receptors ; analysis ; Immunohistochemistry ; Integrin beta1 ; analysis ; Islets of Langerhans ; Proliferating Cell Nuclear Antigen ; analysis ; Stem Cells ; cytology ; metabolism ; Trans-Activators ; analysis

Epidermal growth factor receptor (EGFR) is mutated, dysregulated or overexpressed in many epithelial malignancies, and EGFR activation has been found to be important in tumor growth and progression. Anti-EGFR monoclonal antibodies target the extracellular domain of EGFR; and show promising anti-tumor potential at clinical trials without severe side effects. In this article the pharmacokenetics and clinical study of 3 anti-EGFR monoclonal antibodies (cetuximab, panitumumab and nimotuzomab) were reviewed.
Antibodies, Monoclonal ; pharmacokinetics ; therapeutic use ; Antibodies, Monoclonal, Humanized ; Antineoplastic Agents ; therapeutic use ; Cetuximab ; Humans ; Neoplasms ; therapy ; Receptor, Epidermal Growth Factor ; antagonists & inhibitors ; immunology