Construction of an immunochromatographic determination system for N¹,N¹²-diacetylspermine.

BACKGROUND: N(1),N(12)-diacetylspermine (DiAcSpm) is a recently identified tumor marker. Its concentration increases in the urine of cancer patients at early clinical stages. To utilize this characteristic feature and thus contribute to the early detection of cancer, we developed an immunochromatographic determination system for DiAcSpm. METHODS: We examined the factors that affect the performance and stability of our determination system, including antibody selection and the conditions for the formation of stably dispersed antibody-coated gold nanoparticles. We then tested the performance of the system by determining the DiAcSpm concentration in human urine samples. RESULTS: We constructed an immunochromatographic strip using anti-DiAcSpm antibody-coated gold nanoparticles in the conjugate pad and an acetylspermine-protein conjugate (a DiAcSpm mimic) immobilized on the analyzing membrane. The use of the immunochromatographic strip and an immunochromato-reader allowed for the quantitative determination of DiAcSpm in the range of 20 to 700 nM. The analytical values obtained by this method were well correlated with those determined by a colloidal gold aggregation procedure using an automatic biochemical analyzer. The immunochromatographic strip was stable for at least 8 weeks at 50°C. CONCLUSIONS: A competitive immunochromatographic device for DiAcSpm determination was developed in this study. This simple device will contribute to increasing the opportunities for early cancer detection and timely care.

Fecal calprotectin is a useful marker for disease activity in pediatric patients with inflammatory bowel disease.

BACKGROUND: Studies evaluating the correlation between endoscopic disease activity and noninvasive markers are scarce in inflammatory bowel disease (IBD). AIM: The aim of this study is to evaluate the accuracy of the fecal calprotectin (FC) assay as a marker of disease activity of IBD, as determined by an extensive endoscopic scoring system. METHODS: Thirty-five children and adolescents with IBD [17 with ulcerative colitis (UC) and 18 with Crohn's disease (CD)] and 28 healthy volunteers were enrolled. FC levels were determined by ELISA. The sum of Matts' score for UC and the simple endoscopic score for Crohn's disease (SES-CD) were used. The ileal lesions were evaluated by ultrasonography. RESULTS: In UC patients, there was a strong correlation between FC levels and the sum of Matts' score (r=0.838, p<0.01). FC levels were significantly elevated in endoscopically active patients (median 1,562.5 µg/g) as compared to patients in endoscopic remission (median 38.9 µg/g) or healthy controls (median 19.9 µg/g). In CD patients, there was a strong correlation between FC levels and the SES-CD score (r=0.760, p<0.01). The FC levels were significantly higher in endoscopically active patients (median 2,037.5 µg/g) than in endoscopically inactive patients (median 172.5 µg/g) or healthy controls (median 19.9 µg/g), respectively. The FC levels of patients with ileal wall thickening (median 2,225.0 µg/g) were significantly higher than healthy controls (median 19.9 µg/g) and patients lacking ileal wall thickening (median 17.5 µg/g), respectively. CONCLUSIONS: The FC assay is a useful marker for the detection of mucosal inflammation in pediatric IBD patients.

Biomechanical analysis of combined treatment of high calcium and bisphosphonate in tibia of steroid-treated growing-phase rats.

Childhood systemic diseases are commonly treated with steroids. Consequently, steroid-induced osteoporosis is often observed as a side effect of steroid therapy. However, osteoporosis of tibia resulting from steroid therapy has not been reported yet. Herein we constructed a steroid-induced osteoporosis in tibia of the growing phase rats to examine internal structural changes of the bone and tried to find out the effect of bisphosphonates as a new and early treatment method. Biomechanical analysis was performed using two-dimensional microdensitometry and three-dimensional pQCT method. In addition, the following evaluations were carried out: noninvasive bone strength measurements in steroid-induced osteoporotic rat tibiae; comparing the effectiveness of single high-calcium diet versus combined treatment of high calcium and bisphosphonate for osteoporosis; and quantitative measurement of four elements (Ca, P, Mg, Zn) in bone matrix. Our data suggested that a combined treatment of high calcium and bisphosphonate was an effective new method to improve and treat steroid-induced osteoporosis in childhood.

[Improvement of total prostate specific antigen(PSA) assay from the "Skewed molar-response" to the "Equimolar-response" by utilizing anti free-PSA monoclonal antibodies].

Prostate specific antigen(PSA) is widely used as a marker for screening and monitoring prostate cancer. However, there are several assay methods, which often give different PSA values for the same patient sample. A possible cause of these discrepancies might be the varied immunoreactivity with free-PSA and complex-PSA among methods. This study revealed that pre-treatment of samples with anti-free-PSA monoclonal antibodies improved polyclonal antibodies-based non equimolar PSA assay to equimolar assay. This might be achieved by that the monoclonal antibodies bind to free-PSA and then change its reactivities with polyclonal antibodies to those similar to complex-PSA.