Interaction Between Gatifloxacin and Bovine Serum Albumin

Aim To study the reaction mechanism between gatifloxacin and bovine serumalbumin (BSA) at different pHs. Methods Fluorescence spectra and UV absorbance spectra were used.Results The binding constants were determined from a double reciprocal Lineweaver-Burk curves atdifferent pHs. The binding distance r under normal physiological condition was obtained according toFoster theory of non-radiative energy transfer. The binding force between gatifloxacin and BSA wasinferred by thermody-namical coordination. Conclusion The interaction between gatifloxacin and BSAseems to be strong and the main binding force is electrostatic force.

Primary Culture of Bovine Mammary Epithelial Cells

[ Objective] To investigate the feasibility of the primary culture of bovine mammary epithelial cells in biochemical incubator. [ Method] In vitro, bovine mammary epithelial cells were isolated and cultured by the tissue explant method in order to investigate the optimal culture conditions. The morphology observation and identification of the cultured cells were performed by inverted microscope observation, Giemsa staining and cytokeratin immunohistochemistry. [ Result] Observed with inverted microscope, most of the bovine mammary epithelial cells were polygonal and displayed typical slabstone-like appearance. As it can be seen from cell staining results, the cell body was big and the nucleus was stained dark blue and was round or oval in shape, with clearly visible nucleoli, generally 2 -4 nucleoli. The tissue-specific expression of cytokeratin 14 and cytokeratin 18 genes in mammary epithelial cells was identified by cytokeratin immunohistochemistry. [ Conclusion] Primary bovine mammary epithelial cells were successfully cultured in biochemical incubator.

Effect of BSA on RAPD Analysis of Cynomorium songaricum

[Objective] The objective of the study was to study the role played by BSA in Random Amplified polymorphic DNA(RAPD).[Method]The improvement of RAPD amplification was observed by adding BSA in the analysis of Cynomorium songaricum RAPD.[Result] The result showed that in the process of Cynomorium songaricum RAPD analysis,the effect of amplification improved significantly and the dosage of Taq enzyme declined by adding BSA.The suitable concentration of BSA used in RAPD of Cynomorium songaricum Rupr was 2 μg/μl.[Conclusion]It is feasible to add BSA to improve the RAPD analysis of plants.This study has provided foundation for the application of BSA in RAPD analysis.

Bovine Serum Albumin (BSA) Microspheres Containing Methotrexate (MTX) I.Pharmaceutical Aspects

Microspheres Ⅰ,Ⅱ and Ⅲ were produced by emulsion technique.Microsphere I was solidified by glutaraldehyde crosslinking,microsphere Ⅱ was solidified by glutaraldehyde crosslinking and further treated with glycine solution and microsphere Illwas solidified by heating denaturation only.The results showed that the microsphere diameter produced by cross[inking was bigger than that prepared by heating.The microsphere Ⅱ had higher hydrophilicity than Microsphere I had.The methotrexate (MTX) contents in microspheres Ⅰ and Ⅱ were 2.73±0.053%,2.87±0.119% respectively. microsphere Ⅲ was only blank microspheres with MTX adsorbed on their surfaces.In vitro release studies,microspheres I and I have maintained sustained release of MTX till the next day,it was found that the drug releases from microspheres Ⅰ and Ⅱ were governed by Higuchi diffusion law.

Synthesis and Adsorption Study of BSA Surface Imprinted Polymer on CdS Quantum Dots

A new bovine serum albumin （BSA） surface imprinting method was developed by the incorporation of quantum dots （QDs） into molecularly imprinted polymers （MIP）, which can offer shape selectivity. Preparation and adsorption conditions were optimized. Physical appearance of the QDs and QDs-MIP particles was illustrated by scanning electron microscope images. Photoluminescence emission of CdS was quenched when rebinding of the template.The quenching of photoluminescence emissions is presumably due to the fluorescence resonance energy transfer between quantum dots and BSA template molecules. The adsorption is compiled with Langmuir isotherm, and chemical adsorption is the rate-controlling step.The maximum adsorption capacity could reach 226.0 mg/g, which is 142.4 mg/g larger than that of undoped BSA MIP. This study demonstrates the validity of QDs coupled with MIP technology for analyzing BSA.

Effect of Pore-size of Mesoporous SBA-15 on Adsorption of Bovine Serum Albumin and Lysozyme Protein

In this paper,the effects of pore-size of SBA-15 on the adsorption kinetics and equilibrium of large protein molecules Bovine serum albumin(BSA)and lysozyme(LYS)have been investigated.The mesoporous molecular sieve SBA-15 with six different pore sizes were synthesized with P123 triblock copolymer as the template agent,and 1,3,5-trimethylbenzene(TMB)and isopropyl alcohol as the pore-expanding agent.The samples were characterized by N2 adsorption/desorption,Scanning Electron Microscopy(SEM),Transmission Electron Microscopy(TEM)and X-Ray Diffraction(XRD).It is found that BSA and LYS were adsorbed rapidly on SBA-15 materials with large pores.The BSA adsorption capacity of sieve with the pore diameter of 21.4 nm reached 500 mg·g-1 within 25 minutes.However,if the pore diameter was smaller than 14 nm,the BSA adsorption capacity of the sieve was only about 220 mg·g-1.The adsorption equilibrium data fits in the Langmuir model,where the coefficient of effective use of specific area of mesoporous molecular sieve was found to be 0.03,0.18,0.37 and 0.48,corresponding to the pore diameter of 10.1 nm,13.2 nm,15.4 nm and 21.4 nm,respectively.The equilibrium loading amount of LYS on SBA-15 materials with pore size of 15.4 nm could be up to 1000 mg·g-1.The coefficient of effective use of surface area of mesoporous molecular sieve with diameter of 3.9 nm,7.4 nm,10.1 nm,13.2 nm and 15.4 nm was 0.10,0.47,0.56,0.71 and 0.79,respectively.It is also noted that greater pore size of mesoporous molecular sieve would lead to a higher coefficient of effective use of surface area.

Dynamic Behaviors and Morphology Change of Anionic Phospholipid DPPG Monolayer Caused by Bovine Serum Albumin at Air-Water Interface

The interaction between bovine serum albumin （BSA） and the anionic 1.2-dipalmitoyl-snglycero- 3-（phospho-rac-（1-glycerol）） （sodium salt） （DPPG） phospholipid at different subphase pH values was investigated at air-water interface through surface pressure measurements and atomic force microscopy （AFM） observation. By analyzing surface pressure-mean molecular area （π-A） isotherms, the limiting molecular area in the closed packing state-the concentration of BSA （Alim-[BSA]） curves, the compressibility coefficient-surface pressure （CS-1-π） curves and the difference value of mean molecular area-the concentration of BSA （ΔA-[BSA]） curves, we obtained that the mean molecular area of DPPG monolayer became much larger when the concentration of BSA in the subphase increased at pH=3 and 5. But the isotherms had no significant change at different amount of BSA at pH=10. In addition, the amount of BSA molecules adsorbed onto the lipid monolayer reached a threshold value when [BSA]〉5×10-8 mol/L for all pHs. From the surface pressure-time （π-t） data, we obtained that desorption and adsorption processes occurred at pH=3, however, there was only desorption process occurring at pH=5 and 10. These results showed that the interaction mechanism between DPPG and BSA molecules was affected by the pH of subphase. BSA molecules were adsorbed onto the DPPG monolayers mainly through the hydrophobic interaction at pH=3 and 5, and the strength of hydrophobic interaction at pH=3 was stronger than the case of pH=5. At pH=10, a weaker hydrophobic interaction and a stronger electrostatic repulsion existed between DPPG and BSA molecules. AFM images revealed that the pH of subphase and [BSA] could affect the morphology features of the monolayers, which was consistent with these curves. The study provides an important experimental basis and theoretical support to understand the interaction between lipid and BSA at the air-water interface.

Improvement of HydrophUicity and Blood Compatibility on Polyethersulfone Membrane by Blending Sulfonated Polyethersulfone

Polyethersulfone(PES) is widely used as biomaterials due to its thermal stability,mechanical strength,and chemical inertness.Nevertheless,their blood compatibility is still not adequate for hemodialysis and blood purification.In this study,the sulfonated polyethersulfone(SPES) was synthesized through an electrophilic substitution reaction,and PES/SPES blending membranes were prepared.The characterization of the SPES was studied by FTIR.The water adsorption and water contact angle experiments show that the hydrophilicity of PES/SPES blend membrane was improved as for the sulfonate group existing in the SPES.Moreover,PES/SPES blend membrane could effectively reduce bovine serum albumin adsorption and prolong the blood coagulation time compared with the PES membrane,thereby improving blood compatibility.

Role of the receptor for advanced glycation end products in hepatic fibrosis

AIM： To study the role of advanced glycation end products （AGE） and their specific receptor （RAGE） in the pathogenesis of liver fibrogenesis. METHODS： In vitro RAGE expression and extracellular matrix-related gene expression in both rat and human hepatic stellate cells （HSC） were measured after stimulation with the two RAGE ligands, advanced glycation end product-bovine serum albumin （AGE- BSA） and N＇-（carboxymethyl） lysine （CML）-BSA, or with tumor necrosis factor-α （TNF-α）. In vivo RAGE expression was examined in models of hepatic fibrosis induced by bile duct ligation or thioacetamide. The effects of AGE-BSA and CML-BSA on HSC proliferation, signal transduction and profibrogenic gene expression were studied in vitro. RESULTS： In hepatic fibrosis, RAGE expression was enhanced in activated HSC, and also in endothelial cells, inflammatory cells and activated bile duct epithelia. HSC expressed RAGE which was upregulated after stimulation with AGE-BSA, CML-BSA, and TNF-α.RAGE stimulation with AGE-BSA and CML-BSA did not alter HSC proliferation, apoptosis, fibrogenic signal transduction and fibrosis- or fibrolysis-related gene expression, except for marginal upregulation of procollagen α1（ I ） mRNA by AGE-BSA. CONCLUSION： Despite upregulation of RAGE in activated HSC, RAGE stimulation by AGE does not alter their fibrogenic activation. Therefore, RAGE does not contribute directly to hepatic fibrogenesis.

Induction of pancreatic duct cells of neonatal rats into insulin-producing cells with fetal bovine serum: A natural protocol and its use for patch clamp experiments

AIM： To induce the pancreatic duct cells into endocrine cells with a new natural protocol for electrophysiological study. METHODS： The pancreatic duct cells of neonatal rats were isolated, cultured and induced into endocrine ceils with 15% fetal bovine serum for a period of 20 d. During this period, insulin secretion, MTT value, and morphological change of neonatal and adult pancreatic islet cells were comparatively investigated. Pancreatic β-cells were identified by morphological and electrophysiological characteristics, while ATP sensitive potassium channels （KATP）, voltage-dependent potassium channels （Kv）, and voltage-dependent calcium channels （KcA） in β-cells were identified by patch clamp technique. RESULTS： After incubation with fetal bovine serum, the neonatal duct cells budded out, changed from duct-like cells into islet clusters. In the first 4 d, MTT value and insulin secretion increased slowly （MTT value from 0.024 ±0.003 to 3.028±0.003, insulin secretion from 2.6±0.6 to 3.1±0.8 mIU/L）. Then MTT value and insulin secretion increased quickly from d 5 to d 10 （MTT value from 0.028 ±0.003 to 0.052±0.008, insulin secretion from 3.1±0.8 to 18.3±2.6 mIU/L）, then reached high plateau （MTT value 〉0.052±0.008, insulin secretion 〉18.3±2.6 mIU/L）. In contrast, for the isolated adult pancreatic islet cells, both insulin release and MTT value were stable in the first 4 d （MTT value from 0.029±0.01 to 0.031±0.011, insulin secretion from 13.9±3.1 to 14.3±3.3 mIU/L）, but afterwards they reduced gradually （MTT value 〈0.031 ±0.011, insulin secretion 〈8.2±1.5 mIU/L）, and the pancreatic islet cells became dispersed, broken or atrophied correspondingly. The differentiated neonatal cells were identified as pancreatic islet cells by dithizone staining method, and pancreatic β-cells were further identified by both morphological features and electrophysiological characteristics, i.e. the existence of recording currents from KATP, Kv, and KCA. CONCLUSION： Islet cells differentiated from neonatal pancreatic duct cells with the new natural protocol are more advantageous in performing patch clamp study over the isolated adult pancreatic islet cells.

Biological,antibacterial activities and electrochemical behavior of borided commercially pure titanium in BSA-containing PBS

The effects of boride coating on the bioactivity, antibacterial activity, and electrochemical behavior of commercially pure titanium(CP-Ti) in phosphate buffer solution(PBS) with bovine serum albumin(BSA) were studied. The grazing incidence X-ray diffraction(GIXRD) pattern confirmed the formation of a Ti B/Ti B2 coating via boriding process. Scanning electron microscopy(SEM) observation indicated that the Ti B2 cross-linked particles covered the Ti B whiskers. Water contact angle measurements revealed that boriding led to the formation of a surface with intermediate water affinity. Potentiodynamic polarization(PDP) assays demonstrated that the Ti B/Ti B2 coating had acceptable passivation behavior in BSA-containing PBS. Electrochemical impedance spectroscopy(EIS) measurements revealed that the passivation behavior of the CP-Ti and the borided samples was improved by increasing exposure time. Based on the Mott-Schottky(M-S) tests, it was realized that the charge carriers of passive films of both samples decreased with increasing exposure time in BSA-containing PBS. The bioactivity test results in a simulated body fluid showed that the Ti B/Ti B2 coating switched the CP-Ti from bioinert to bioactive material. Finally, the antibacterial activity test of the Ti B/Ti B2 coating against Escherichia coli and Staphylococcus aureus indicated 99% antibacterial activity.

Effects of appendectomy and oral tolerance on dextran sulfate sodium colitis

AIM： To evaluate the concomitant effects of appendec- tomy and oral tolerance on colitis.METHODS： Delayed-type hypersensitivity （DTH） was investigated at a 7-d interval after ovalbumin （OVA） ad- ministration and immunization under normal and colitis conditions in appendectomized or sham-operated mice. Pathological scores for the colon were graded after in- gestion of colon-extracted protein （CEP） and induction of dextran sulfate sodium （DSS） colitis in appendecto- mized or sham-operated mice. Thereafter, Thl and Th2 in Peyer＇s patches and spleen lymphocytes were de- tected in CEP-treated and bovine serum albumin （BSA）-treated control mice.RESULTS： In appendectomized mice, DTH was not inhibited at day 7 after OVA administration and at the initial phase of DSS colitis, whereas it was inhibited at day 14 and day 21. However, in sham-operated mice, it was inhibited during the whole procedure and the onset of DSS colitis. The protective role of CEP against DSScolitis was present in sham-operated mice, with pre- dominant improvement of colonic pathological changes, while vanished in the appendectomized mice. A shift from Thl to Th2 in Peyer＇s patches resulted from a de- crease of Thl cells with the ingestion of CEP. Compared with BSA in the sham-operated group, no predominant changes were observed in the appendectomized mice.CONCLUSION： Appendectomy interferes with the pro- tective role of CEP in DSS colitis via a shift from Th2 to Thl during oral tolerance induction.

Bovine serum albumin:An efficient and green biocatalyst for the one-pot four-component synthesis of pyrano[2,3-c]pyrazoles

The use of biocatalysts is attracting an increasing amount of attention in chemical catalysis.Here,we have shown that bovine serum albumin（BSA）,a ubiquitous,inexpensive,non-enzymatic transport protein,can serve as an efficient,retrievable catalyst in the one-pot four-component reaction of aryl aldehydes,malononitrile,hydrazine hydrate,and ethyl acetoacetate for the synthesis of pyrano[2,3-c]pyrazoles under mild reaction conditions.The BSA biocatalyst also displayed a high catalytic affinity for acyclic/cyclic ketones to yield the corresponding pyrano[2,3-c]pyrazoles or their spirocyclic variants.The BSA could be used for at least five cycles without serious loss of catalytic activity.This novel,efficient protocol has the merits of high yield,operational simplicity,and a relatively benign environmental impact.Moreover,the method extends the promiscuity of BSA as a biocatalyst.

Preparation of magnetic gelatin-starch microspheres and adsorption performance for bovine serum album

The magnetic gelatin-starch microspheres were prepared by modified emulsion cross-linking method with glutaraldehyde as the cross-linking agent. The structure, size distribution as well as morphology of magnetic microspheres were investigated by FT-IR spectrometer, dynamic laser scattering analyzer and scanning electron microscope, respectively. Bovine serum album(BSA)was chosen as model protein, and the adsorption processes were carried out under diversified conditions including BSA initial concentration, p H value, adsorption time and temperature to evaluate the performance of the magnetic microspheres. The average diameter of optimized spherical magnetic microspheres is 1.6 μm with excellent dispersivity, and the saturation magnetization is found to be equal to 1.056×10-2 A·m2. The adsorption isotherm of the BSA on the magnetic microspheres basically obeys the Langmuir model, with a maximum adsorption capacity of 120 mg/g and an adsorption equilibrium constant of 1.60 mL/mg.

Effects of Pressure on Bubble Size and Separation of BSA by a Semi-batch Foaming Process

Experiments were conducted to obtain the values of the Sauter bubble size, enrichment and recovery of bovine serum albumin （BSA） in a semi-batch col- umn fitted with a stainless steel sparger at elevated pressure. The effects of Sur- face tension, surfactant concentration, foam/solution height ratio and air flow rate on the separation performance were investigated, and the results showed that good en- richments and recoveries can be achieved for bovine serum albumin operated at el- evated pressures. Especially the size of bubbles generated by the stainless steel sparger was smaller at higher pressures which is favorable to the foam separation process. Furthermore, the separation mechanism of bovine serum albumin operated at elevated pressure was also discussed.

Initiation of primary cell culture from amphioxus Branchiostoma belcheri tsingtauense

Amphioxus, a cephalochordate, is an important model fish for studies in evolution and comparative biology. A successful cell culture from amphioxus tissues in vitro would help understanding some basic issues. To determine the optimal culture conditions for proliferation of amphioxus cells, primary cultures were initiated from buccal cirri, tail, gill, gut and metapleural fold of amphioxus Branchiostoma belcheri tsingtauense. The media tested were L-15, F-12, M 199, MEM, DMEM, PRMI 1640 and LDF, each was supplemented with 20% fetal bovine serum. The optimal conditions include tail tissue cultured in L-15 or F-12 with supplement of 20% FBS and 1.5% NaCl at about 25℃.

In vitro long-term culture and differentiation of mouse spermatogonia stem cells

The studies from 7 or 8 days old mice were used to prepare the spermatogonial stem cells. The isolation and purification of spermatogonial stem cells were done by means of the Percoll discontinual density gradient concentration. The cells of the 3rd band were collected and cultured in vitro in DMEM supplemented with 2.5% or 10% fetal bovine serum （FBS）. The results showed that with the feeder layer and 2.5% serum, the spermatogonial stem cells could proliferate, differentiate last more than 4 months.

Effect of daidzein on milk yield,components of milk and hormones in serum of dairy cows

Four Holstein dairy cows in the 7th month of late lactation were sampled, and self-control method was used. Daidzein was added to the concentrated feed at the dose of 10mg/kg during the treatment stage. Results showed that daidzein lessened the declining tendency of milk yield in late lactation and increased the milk yield to some extents. Lactoprotein was evidently increased (P<0.01), while milkfat was not affected evidently. The level of T4 in serum was evidently increased (P<0.05); the levels of GH, PRL, E2 and TSH in serum were prone to rising while T3 was prone to decreasing . It was concluded that daidzein could indirectly affect milk yield and components of milk by regulating the levels of intrinsic hormones.

Adsorption of the Enantiomers of Tryptophan on Stationary Phase Bonded with Bovine Serum Albumin

Frontal analysis is frequently applied to measuring single or multi-component adsorption isotherms. In this work, the competitive adsorption isotherm data of two enantiomers of tryptophan were obtained by competitive frontal analysis. The stationary phase in the column was silica-immobilized bovine serum albumin (BSA) by the derivative method, and the mobile phase was a phosphate buffer. These isotherm data were fitted by the competitive Bilangmuir model. This model can account for the behavior of both tryptophan enantiomers and these profiles were found to fit the experimental band profiles (square error is 0.999 6). The parameters obtained were used in numerical calculations to predict the band profiles of the racemic mixtures of tryptophan. The equilibrium-dispersive model provides satisfactory prediction, with minor differences between the calculated and the experimental profiles.