Decreased serum CXCL12/SDF-1 concentrations may reflect disease severity of non-traumatic osteonecrosis of femoral head.

OBJECTIVE: The current study was performed to investigate the potential association of serum CXCL12 with disease severity in non-traumatic ONFH. METHODS: This study enrolled 182 patients with non-traumatic ONFH and 182 age- and gender-matched healthy controls. The CXCL12 levels in serum were measured by enzyme-linked immunosorbent assay. Meanwhile, serum levels of procollagen type I (PINP) and Interleukin-33(IL-33) were also detected. The radiographic severity was determined by FICAT grade. Clinical severity was evaluated by visual analogue scale (VAS), Harris Hip Score (HHS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Among the non-traumatic ONFH, 90 patients ONFH received total hip arthroplasty, the localization and expression of the CXCL12 protein and mRNA were detected by immunohistochemistry, Western blot analysis, RT-PCR and in necrotic area and adjacent non-necrotic area from lesioned femoral neck from ONFH patients and healthy femoral head from femoral neck fracture patients. Receiver operating characteristic (ROC) curve analysis was carried out to confirm the diagnostic value serum CXCL12, PINP and IL-33 with regard to the FICAT grade. RESULTS: Serum CXCL12 levels were significantly lower in non-traumatic ONFH patients compared with healthy controls. CXCL12 mRNA and protein expressions were both significantly decreased in necrotic area in comparison with non-necrotic area and healthy femoral head. Serum CXCL12 concentrations were drastically reduced in patients with FICAT stage 4 compared with stage 3, and CXCL12 concentrations in patients with stage 3 were markedly lower than stage 2. Serum CXCL12 levels were negatively related to FICAT grading. In addition, Serum CXCL12 concentrations were also negatively related to VAS, WOMAC scores and positively correlated with HHS scores. Meanwhile, serum CXCL12 levels were positively correlated with serum PINP and negatively correlated with IL-33 levels. ROC curve analysis implicated that decrease CXCL12 in serum may act as a favorable marker for FICAT grade. CONCLUSIONS: Decreased serum CXCL12 concentrations may reflect disease severity of non-traumatic ONFH.

Synthesis and Application of A Flavone-based Fluorescent Probe for Detection of Hydrazine / 分析化学

A fluorescence enhancement probe (ZY8) for the detection of N2H4was designed and synthesized by employing 3-hydroxyflavone as a fluorophore,and its spectral properties had been investigated. The results showed that ZY8 had relatively good selectivity and specificity to N2H4in Tris-HCl-ethanol solution (9:1, V/V, pH 7.40). The fluorescent intensity of ZY8 exhibited good linear relationship with concentration of N2H4in the concentration range of 1.6×10-7mol/L-6.2×10-5mol/L,and its detection limit was estimated to be 1. 6×10-7mol/L. ZY8 itself had weak fluorescence, upon addition of N2H4, an approximate 9-fold fluorescence enhancement was observed, and the color of the solution changed from light grayish green to bright grass-green at UV light of 365 nm. So ZY8 might be used to the visual recognition of N2H4. ZY8 could detect N2H4in near-physiological pH range, and it had fast response and strong anti-interference ability. Moreover,ZY8 could be loaded as test paper for naked-eye detection of N2H4at mmol/L level in water solution,and it was also applied in the determination of N2H4in various water samples by the standard addition recovery experiments, with the recovery ratio ranged from 96.0% to 104.2% %, and RSD of all< 4%. The results of this study demonstrated that ZY8 had potential application to the detection of N2H4in the monitoring of environmental pollution.