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Abstract  

Quality Control (QC) of radiopharmaceuticals is important, providing products of high standards. The current study refers to an enzymic radioiodination method applied to the labeling of antibodies used in nuclear medicine and to the respective QC procedures. Readily available materials such as125I, polyclonal immunoglobulin G (IgG) and a collection of simple chromatographic techniques helped establish a QC protocol suitable for the radiochemical evaluation of radioiodinated biomolecules. A high pre-purification radiolabeling yield (90%) for total protein was detected by paper electrophoresis (PE) and size exclusion chromatography (SEC), but only the inclusion of SDS-PAGE confirmed the existence of “self-iodination” of lactoperoxidase (LPO) and revealed the true radiolabeling yield for125I-IgG (79%).

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. Baptista
,
D. Vieira
,
A. Galisteo Júnior
,
O. Higa
,
M. Casare
,
C. Yonamine
,
P. Caproni
,
L. Campos
,
H. de Andrade Júnior
,
P. Spencer
, and
N. Nascimento

Abstract  

In this work, the authors investigated the immunological behavior of bothropstoxin-I (BTHX-1), before and after irradiation process, and also the influence of scavengers substances on protein alterations induced by free radical production. Structural modifications were investigated by SDS-PAGE in reducing or non-reducing conditions. In vitro cytotoxicity assay was performed to test average toxic activities of BTHX-I. BALB/c Isogenic mice were immunized with irradiated or non-irradiated (native) forms of BTHX-I and antibody titers and isotypes were determined by ELISA method. Expression of murine cytokines was analyzed by using expression data obtained by quantitative real-time PCR (qPCR) assays. The results indicate that irradiation of proteins leads to significant structural modifications, and also changes the cytokines profile during immunization process, regarding a suitable approach to new immunogenic production.

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This work describes the induction, purification and partial biochemical characterizations of an antimicrobial protein from the housefly larvae induced by ultrasonic wave. It has been purified to apparent homogeneity by ammonium sulfate precipitation followed by Sephadex G-75, Bio-gel P6 gel filtration, and CM-Sepharose Fast Flow cation exchange chromatography. The protein is a cationic protein with an apparent molecular weight of 16315 Da determined by no-denaturing electrophoresis and SDS-PAGE, respectively. Biochemical profile assays show that this protein has good thermal stability, and repeatedly frozen and defrosted durability. The optimum pH for antimicrobial activity is around pH5. The antimicrobial range of the protein includes Gram-positive, Gram-negative bacteria and some fungi. Results of the membrane permeability assays suggest that the probable mode of action of this protein is membrane-disrupting mechanism.

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Abstract  

Biochemical techniques, including pH variation, outsalting, ultracentrifugation, gel filtration chromatography and electrophoresis, etc., have been employed together with instrumental neutron activation analysis (INAA) to study the rare earth elements (REE) bound proteins in the natural plant fern,Dicranopteris dichitoma. INAA was also used to identify whether the proteins were bound firmly with REE. The results obtained show that two REE bound proteins (RBP-I and RBP-II) have been separated. The molecular weight of RBP-I on Sephadex G-200 gel column is about 8·105 Daltons and that of RBP-II is less than 12,400 Daltons, respectively. However, SDS-PAGE of the two proteins shows that they mainly have two protein subunits with MW 14,100 and 38,700 Daltons. They are probably conjugated proteins, glycoproteins with different glyco-units.

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High molecular weight glutenin and 1BL.1RS translocation employing the standard sodium dodecyl sulphate (SDS-PAGE) and acid (A-PAGE) polyacrylamide gel electrophoresis methods were classified in 43 Slovak wheat cultivars registered between 1976 and 2006. Total number of 9 alleles was detected at all Glu-1 loci. The most frequent HMW-GS alleles were “Null” for Glu-1A , 7+9 for Glu-1B and 5+10 for Glu-1D , respectively. At the same time these alleles also constituted the most frequent HMW-GS genotype and phenotype-0, 7+9, 5+10. Such HMW-GS combination was found in 48.8% of all genotypes analyzed in Triticum aestivum L. ssp. aestivum . Eleven different HMW-GS genotype-phenotype combinations were found, occurring at various frequencies.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Alireza Khorami-Moghadam
,
Amir Jalilian
,
Kamal Yavari
,
Bahram Bolouri
,
Ali Bahrami-Samani
, and
Mohammad Ghannadi-Maragheh

Abstract  

Antiangiogenic monoclonal antibodies in combination with therapeutic radionuclides are potential targeted therapy agents in cancer. In this study, bevacizumab was successively labeled with [166Ho]HoCl3 after conjugation with DOTA-NHS-ester with a radiochemical purity of higher than 95% (RTLC). The conjugates were purified by molecular filtration, the average number of DOTA conjugated per mAb was calculated and total concentration was determined by spectrophotometric method and the average chelate to antibody ratio (c/a) for the conjugate used in this study was 5.8:1 and protein integrity experiments (SDS-PAGE). The biodistribution studies in wild-type rats demonstrate a similar pattern to the other radiolabeled anti-vascular endothelial growth factor A (VEGF-A) immunoconjugates. 166Ho-DOTA-bevacizumab is a potential compound for therapy/imaging of VEGF-A expression in oncology.

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Prolonged (120 days) oral administration of a beta adrenoceptor agonist, isoproterenol hydrochloride (dose = 1.5 mg/kg body weight) resulted in an increase in the live weight of growing chicks (Gallus domesticus). Measurement of dry muscle mass and total proteins in muscle homogenates from M. pectoralis major, M. pectoralis minor suggested a muscle hypertrophy largely responsible for this live weight increase. Further, an increase in organ weight and total tissue proteins supported cardiac hypertrophy in chicks as a result of isoproterenol administration. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed alterations in actin myosin profiles implying a drug induced change in phenotypic expression of myofibrillar component of both skeletal and cardiac muscle. The results suggest that prolonged treatment of chicks produced changes that were not much different from those recorded immediately within a fortnight.

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Proteins of pea variety Kwestor, grown in Poland, were modified with acetic or succinic anhydride (0.01–1.0 g/g anhydride/protein). Degree of acylation, electrophoretic properties (SDS-PAGE) and immunoreactivity (by ELISA) were studied. The study indicates that not only the degree of acylation but also the type of anhydrides affected the extent of changes in the immunoreactivity of individual pea proteins. The greatest reductions in the immunoreactivity of albumins and legumin were observed during acylation with 0.2 g anhydrides (by 91–99% and 79–97% during succinylation and acetylation, respectively). The lowest immunoreactivity of vicilin fraction was found when 1.0 g of anhydride was used (about 6% during succinylation and 14.7% during acetylation as compared to the immunoreactivity of vicilin in native pea proteins).

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Abstract  

Optimum temperature and pH for the isolation of soy protein isolate (SPI) from soy protein concentrate (SPC) were established. Enzymatic hydrolysis of SPI with enzymes of different specificities such as trypsin, chymotrypsin, papain and urease was carried out and the products of hydrolysis were characterized by molecular mass determination [sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)] and thermal techniques [differential scanning calorimetry (DSC) and thermogravimetric analysis (TG)]. Enzymatic hydrolysis resulted in a significant reduction in molecular masses. However the thermal stability of hydrolysed SPI was similar to native SPI indicating that it is independent of molecular mass. DSC studies indicated an increase in temperatures of endothermic transition associated with SPI denaturation and loss of absorbed moisture in samples of lower molecular masses.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
R. Minayoshi
,
T. Ohyama
,
N. Kinugawa
,
J. Kamishima
,
T. Ogi
,
K. Ishikawa
,
M. Noguchi
,
H. Suganuma
,
K. Takahashi
,
S. Enomoto
, and
M. Yanaga

Abstract  

The concentrations of essential trace elements and proteins in cytosolic fraction of hepatic cells of mice fed with Zn-deficient diet (Zn-def, mice) and control were determined by ICP-MS and BCA protein assay method, respectively, after division into forty fractions by gel filtration chromatography. The concentrations of zinc and proteins decreased in the 14–17th fractions of Zn-def, mice, whereas cobalt concentrations increased in the 14, 17, and 18th fractions. However, no significant differences were found on the gel after SDS-PAGE for the 12–21st fractions, although the BCA protein assay date showed the decrease of protein amounts in 13–15th fractions of Zn-def. mice.

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