ABSTRACT
Based on ultra-high-performance liquid chromatography-quadrupole/time of flight mass spectrometry (UPLC-Q-TOF MS/MS),a post targeted screening strategy using high resolution mass spectrometry under data independent acquisition was established,and successfully applied to screen and identify unknown toxicants in food poisoning patients' vomit and feces.After solvent extraction,the samples were separated and analyzed on a reversed-phase C18column using a gradient elution program of 5 mmol/L ammonium formate and 0.1% formic acid aqueous solution(A) and 0.1% formic acid in acetonitrile solution (B).All-ions MS/MS information of samples was obtained using Q-TOF MS(ESI+) in MSE mode,followed by peak recognition and library searching using the UNIFI Scientific Information System,as a result,suspected toxic compound α-solanine was primarily detected.Furthermore,the related chemicals including hydrolysates and metabolites were identified in both samples based on post-targeted screening strategy,such as α-chaconine,β-chaconine,γ-solanine/chaconine and solanidine.The concentration of α-solanine in both samples was approximately 0.1 mg/kg by one-point calibration method,the total amount of solanine analogues in two samples was about 0.5 mg/kg and 0.6 mg/kg respectively through normalization of peak area.The high resolution mass spectrometry screening strategy established here could provide efficient screening method for rapid detection and identification of toxicants in unknown food poisoning.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the risk factors for hearing impairment induced by cytomegalovirus (CMV) infection in children.</p><p><b>METHODS</b>One hundred and fifty-eight children diagnosed with CMV infection were enrolled as subjects. Based on the results of the brainstem auditory evoked potential (BAEP) test, patients were classified into normal hearing group (n=117; BAEP≤35) and abnormal hearing group (n=41; BAEP>35). A retrospective analysis was performed on the general information, routine blood indices, liver function, copy number of CMV-DNA in urine and breast milk. The receiver operating characteristic (ROC) curve was used to predict the copy number of CMV-DNA resulting in abnormal BAEP. The Spearman rank correlation analysis was used to test the correlations of the copy number of CMV-DNA in urine with the degree of hearing impairment and platelet count.</p><p><b>RESULTS</b>The incidence rates of platelet abnormality and abnormal liver function and the copy number of CMV-DNA in urine were significantly higher in the abnormal hearing group than in the normal hearing group (P<0.01). According to the ROC curve, the copy number of CMV-DNA in urine had a sensitivity of 46.3% and a specificity of 93.2% in predicting hearing impairment when it reached 1.415×10(6) per mL. The results of correlation analysis showed that the degree of hearing impairment was positively correlated with the copy number of CMV-DNA (r=0.382, P<0.01); the platelet count was negatively correlated with the copy number of CMV-DNA in urine (r=-0.233, P=0.003).</p><p><b>CONCLUSIONS</b>An increased copy number of CMV-DNA in urine might be a risk factor for hearing impairment induced by CMV infection. Children are likely to have hearing impairment when the copy number of CMV-DNA reaches 1.415×10(6) per mL. The monitoring of hearing should be strengthened in CMV-infected children with a decreased platelet count.</p>