ABSTRACT
Monoclonal anti-enrofloxacin antibody was prepared for a direct competitive enzyme-linked immunosorbent assay (ELISA) and purification system using monoclonal antibody (mAb) coupled magnetic nanoparticles (MNPs). The IC50 values of the developed mAb for enrofloxacin (ENR), ciprofloxacin, difloxacin, sarafloxacin, pefloxacin, and norfloxacin were 5.0, 8.3, 9.7, 21.7, 36.0, and 63.7 ng/mL, respectively. The lowest detectable level of ENR was 0.7 ng/mL in the prepared ELISA system. To validate the developed ELISA in the food matrix, known amounts of ENR were spiked in meat and egg samples at 10, 20 and 30 ng/mL. Recoveries for ENR ranged from 72.9 to 113.16% with a coefficient of variation (CV) of 2.42 to 10.11%. The applicability of the mAb-MNP system was verified by testing the recoveries for ENR residue in three different matrices. Recoveries for ENR ranged from 75.16 to 86.36%, while the CV ranged from 5.08 to 11.53%. Overall, ENR-specific monoclonal antibody was prepared and developed for use in competitive to ELISAs for the detection of ENR in animal meat samples. Furthermore, we suggest that a purification system for ENR using mAb-coupled MNPs could be useful for determination of ENR residue in food.
Subject(s)
Animals , Ciprofloxacin , Enzyme-Linked Immunosorbent Assay , Inhibitory Concentration 50 , Meat , Nanoparticles , Norfloxacin , Ovum , PefloxacinABSTRACT
PURPOSE: Generally, a mucinous carcinoma (Muc) of the colon show higher rates of microsatellite instability (MSI) than a non-mucinous carcinoma (non-Muc). Mutated methylenetetrahydrofolate reductase (MTHFR) brings about low enzyme activity, which may reduce genomic DNA methylation. These processes may be critical for the oncogenic transformation of human cells. We compared the relationship of MSI and MTHFR polymorphism in Muc to that in non-Muc. METHODS: From March 2003 to August 2007, genomic DNA was isolated from whole blood and tissue specimens of 285 colorectal cancer patients (Muc: 31 cases, non-Muc: 254 cases) and 448 normal control patients. These were subjected to MSI analysis and MTHFR genotyping by using PCR-based restriction fragment length polymorphism analyses. RESULTS: MSI was significantly more frequent in the Muc group (40.7%) than in the non- Muc group (14.8%). The frequencies of polymorphism of MTHFR 677C>T were CC (31.5%), CT (57%), and TT (11.5%) in the patient group and 32.4%, 53.1%, and 14.5% in the control group. In the Muc group, the frequencies of polymorphism of MTHFR 677C>T were CC (36%), CT (56%), TT (8%), and in the non-Muc group, they were 31.1%, 57%, and 11.9%. The frequencies of polymorphism of MTHFR 1298A>C were AA (73%), AC (21.3%), and CC (5.7%) in the patient group and 69.6%, 28.6%, and 1.8% in the control group. In the Muc group, the frequencies of polymorphism of MTHFR 1298A>C were AA (50%), AC (30%), and CC (20%), and in the non-Muc group, they were 76%, 20.3%, and 3.7%. The Muc group showed higher frequencies of the CC variant than the non-Muc group (P-value=0.018). No relation between MSI and MTHFR polymorphisms were seen in any comparison of the Muc and the non-Muc groups. CONCLUSIONS: The Muc group showed higher rates of MSI than the non-Muc group, but no definite difference between the Muc and the non-Muc groups was noted in the case of polymorphism of MTHFR 677C>T. However, the TT-type variant showed slightly lower frequencies in the Muc group than in the non-Muc group. On the contrary, the Muc group showed a higher rate of the CC variant in polymorphism of MTHFR 1298A>C. These inconsistent results seem to be due to the small size of the Muc group, so further study is needed.
Subject(s)
Humans , Adenocarcinoma, Mucinous , Colon , Colorectal Neoplasms , DNA , DNA Methylation , Methylenetetrahydrofolate Reductase (NADPH2) , Microsatellite Instability , Microsatellite Repeats , Mucins , Oxidoreductases , Polymorphism, Restriction Fragment Length , Succinimides , TetrahydrofolatesABSTRACT
PURPOSE: To analyze the relationships between homocysteine, folate, MTHFR and TSER polymorphism for postmenopausal women with osteoporotic compression fractures. MATERIALS AND METHODS: Forty-three postmenopausal compression fracture patients and as many normal controls were included. The plasma homocysteine and folate levels were measured using a FPIA (fluorescent polarizing immunoassay) kit. The MTHFR and TSER genotypes were amplified by PCR (polymerase chain reaction) and separated by RFLP (restriction fragment length polymorphism) in a 3.5% agarose gel. RESULTS: The plasma folate level was significantly lower in the postmenopausal women with osteoporotic compression fractures, particularly in the MTHFR 677CT and TSER 2R (-) genotypes. However, the plasma homocysteine level and MTHFR C677T polymorphism were similar to the control group. CONCLUSION: A low folate level and the TSER 2R (-) genotype can be associated with osteoporotic compression fractures in postmenopausal women.
Subject(s)
Female , Humans , Folic Acid , Fractures, Compression , Genotype , Homocysteine , Osteoporotic Fractures , Plasma , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , SepharoseABSTRACT
STATEMENT OF PROBLEM: One of the common problems of dental implant prosthesis is the loosening of the screw that connects each component, and this problem is more common in single implant-supported prostheses with external connection. PURPOSE: The purpose of this study was to examine the changes of detorque values of abutment screws with external connection in different abutment heights. MATERIALS AND METHODS: After cyclic loading on three different abutment heights, detorque values were measured. Abutments were retained with titanium abutment screws tightened to 30 Ncm (30.5 kgmm) with digital torque gauge as recommended by the manufacturer. Replacing abutments, implants and titanium abutment screws with new ones at every measurement, initial detorque values were measured six times. In measuring detorque values after cyclic loading, Avana Cemented Abutments of 4.0 mm collar, 7.0 mm height (Osstem Co., Ltd., Seoul, Korea) were used with three different lengths of 5.0, 8.0, 11.0 mm. Shorter abutments were made by milling of 11.0 mm abutment to have the same force-exercised area of 4.5 mm diameter. Sine curve force (20N-320N, 14Hz) was applied, and detorque values were measured after cyclic loading of 2 million times by loading machine. Detorque values of initial and after-loading were measured by digital torque gauge. One-way ANOVA was employed to see if there was any influence from different abutment heights. RESULTS: The results were as follows : 1. The initial detorque value was 27.8+/-0.93 kgmm, and the ratio of the initial detorque value to the tightening torque was 0.91(27.8/30.5). 2. Measured detorque values after cyclic loading were declined as the height of the abutment increased, that was, 5.0 mm; 22.3+/-0.82 kgmm, 8.0 mm; 21.8+/-0.93 kgmm, and 11.0 mm; 21.3+/-0.94 kgmm. 3. One-way ANOVA showed no statistically significant differences among these (p> 0.05). 4. Noticeable mobility at the implant-abutment interface was not observed in any case after cyclic loading at all.