Search results for "Electrophoresi"
showing 10 items of 1009 documents
Microbial analysis of raw cows' milk used for cheese-making: influence of storage treatments on microbial composition and other technological traits
2010
Raw milk used to produce Grana cheese was subjected to several treatment regimes, including varying temperatures and storage times. Milk from morning and evening milking were transferred to a dairy factory sepa- rately (double delivery) or together (single delivery), after storage at the farm for 12 h; in the former case, milk was stored at 12 or 8°C, whereas, in the latter, it was kept at ambient temperature or 18°C. Values of pH of the vat milk were lower for milk samples kept at room temperature, while other physico-chemical parameters and rheological characteristics tested did not show significant differ- ences linked to the different storage temperatures of milk used for ‘‘Grana Trenti…
Ligand-induced phosphorylation/dephosphorylation of the endogenous bradykinin B2 receptor from human fibroblasts.
1996
We have studied the ligand-induced phosphorylation/dephosphorylation of the bradykinin B2 receptor endogenously expressed in human HF-15 fibroblasts. An antiserum (AS346) to a synthetic peptide (CRS36), derived from the extreme carboxyl terminus of the human B2 receptor, precipitated the receptor from solubilized membranes of HF-15 cells that had been labeled with [32P]orthophosphate. A low basal level of B2 receptor phosphorylation was found in the absence of a ligand. Stimulation of the cells with the B2 receptor agonists bradykinin, [Lys0,Hyp3]bradykinin, kallidin, and T-kinin resulted in a rapid and efficient phosphorylation of the receptor. The B2 receptor antagonist HOE140 and the B1 …
Pre- and Post-translational Regulation of Lysyl Oxidase by Transforming Growth Factor-β1 in Osteoblastic MC3T3-E1 Cells
1995
The final enzymatic step required for collagen cross-linking is the extracellular oxidative deamination of peptidyl-lysine and -hydroxylysine residues by lysyl oxidase. A cross-linked collagenous extracellular matrix is required for bone formation. The goals of this study were to compare the transforming growth factor (TGF)-beta 1 regulation of lysyl oxidase enzyme activity and steady state mRNA levels to changes in COL1A1 mRNA levels in MC3T3-E1 osteoblastic cells. TGF-beta 1 increased steady state lysyl oxidase and COL1A1 mRNA levels in a dose- and time-dependent manner. The increase in lysyl oxidase mRNA levels was transient, peaking at 12 h and 8.8 times controls in cells treated with 4…
Production of biologically active light chain of tetanus toxin inEscherichia coli
1993
AbstractThe activity of the light (L) chain of tetanus toxin, and of mutants constructed by site-directed mutagenesis, was studied by expression and purification of the proteins from E. coli. Wild-type recombinant L chain (pTet87) was active in the inhibition of exocytosis from cultured bovine adrenal chromaffin cells, although at a level 5–15% of that of L chain purified from tetanus toxin. L chain mutants which terminated at Leu-438 (pTet89), or which contained a Cys-to-Ser mutation at residue 439 (pTet88) were equally as active as the full-length recombinant protein. The reduced activity of pTet87 L chain correlated with C-terminal proteolysis of the protein upon purification. A tryptic …
Systematic Comparative Protein Expression Profiling of Clear Cell Renal Cell Carcinoma
2009
Proteome-based technologies represent powerful tools for the analysis of protein expression profiles, including the identification of potential cancer candidate biomarkers. Thus, here we provide a comprehensive protein expression map for clear cell renal cell carcinoma established by systematic comparative two-dimensional gel electrophoresis-based protein expression profiling of 16 paired tissue systems comprising clear cell renal cell carcinoma lesions and corresponding tumor-adjacent renal epithelium using overlapping narrow pH gradients. This approach led to the mapping of 348 distinct spots corresponding to 248 different protein identities. By implementing restriction criteria concernin…
An automatic system for stepwise treatment of solid samples and application to pollution evaluation by measuring ion lixiviation rates in lichens
1999
An automatic system for the stepwise treatment of solid samples is described. The system is controlled by a PC computer that is connected to a burette equipped with a three-way valve, to a peristaltic pump, and to a robot arm through two serial interfaces. In a cycle, the burette introduces a solvent volume in the sample cell, sonication is applied, and, after a fixed time, the pump carries the solvent to the vial selected by the robot arm. Measurements can be performed both in-line and off-line by analyzing the vial series. The program was written in Visual Basic 3. Lixiviation rates of several cations from the lichen Ramalina farinacea were measured by capillary zone electrophoresis using…
Enantioresolution in electrokinetic chromatography-complete filling technique using sulfated gamma-cyclodextrin. Software-free topological anticipati…
2016
Few papers have tried to predict the resolution ability of chiral selectors in capillary electrophoresis for the separation of the enantiomers of chiral compounds. In a previous work, we have used molecular information available on-line to establish enantioresolution levels of basic compounds using highly sulfated β-CD (HS-β-CD) as chiral selector in electrokinetic chromatography-complete filling technique (EKC-CFT). The present study is a continuation of this previous work, introducing some novelties. In this work, the ability of sulfated γ-cyclodextrin (S-γ-CD) as chiral selector in EKC-CFT is modelled for the first time. Thirty-three structurally unrelated cationic and neutral compounds …
Potential of human serum albumin as chiral selector of basic drugs in affinity electrokinetic chromatography-partial filling technique
2006
The enantiomeric resolution of compounds using HSA by means of affinity EKC (AEKC)-partial filling technique is the result of a delicate balance between different experimental variables such as protein concentration, running pH (background electrophoretic buffer (BGE), protein, and compound solutions), and plug length. In this paper, the possibility of using HSA as chiral selector for enantioseparation of 28 basic drugs using this methodology is studied. The effect of the physicochemical parameters, the structural properties of compounds, and compound-HSA protein binding percentages over their chiral resolution with HSA is outlined. Based on the results obtained, a decision tree is proposed…
Differential expression and interaction with the visual G-protein transducin of centrin isoforms in mammalian photoreceptor cells.
2004
Photoisomerization of rhodopsin activates a heterotrimeric G-protein cascade leading to closure of cGMP-gated channels and hyperpolarization of photoreceptor cells. Massive translocation of the visual G-protein transducin, Gt, between subcellular compartments contributes to long term adaptation of photoreceptor cells. Ca(2+)-triggered assembly of a centrin-transducin complex in the connecting cilium of photoreceptor cells may regulate these transducin translocations. Here we demonstrate expression of all four known, closely related centrin isoforms in the mammalian retina. Interaction assays revealed binding potential of the four centrin isoforms to Gtbetagamma heterodimers. High affinity b…
Assignment of the group A rotavirus NSP4 gene into genotypes using a hemi-nested multiplex PCR assay: a rapid and reproducible assay for strain surve…
2009
The rotavirus non-structural protein NSP4 has been implicated in a number of biological functions during the rotavirus cellular cycle and pathogenesis, and has been addressed as a target for vaccine development. The NSP4 gene has been classified into six genotypes (A–F). A semi-nested triplex PCR was developed for genotyping the major human NSP4 genotypes (A–C), which are common in human rotavirus strains but are also shared among most mammalian rotavirus strains. A total of 192 previously characterized human strains representing numerous G and P type specificities (such as G1P[8], G1P[4], G2P[4], G3P[3], G3P[8], G3P[9], G4P[6], G4P[8], G6P[4], G6P[9], G6P[14], G8P[10], G8P[14], G9P[8], G9P…