Search

Background: This study aimed to quantify and compare serum aldosterone (sALD) levels through three different chemiluminescence immunoassays (CLIAs) and liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. Methods: Serum samples from 221 patients with suspected primary aldosteronism (PA) were retrospectively included in this study conducted at the Peking Union Medical College Hospital from June to August in 2017. sALD levels were determined using the LC-MS/MS method and three different CLIA systems, viz., DiaSorin® XL, iSYS and Auto Lumo A2000. Pooled fresh serum samples were used for recalibration. Passing-Bablok regression analysis, correlation matrix, and Bland-Altman plots were used to evaluate the concurrence among ALD levels determined using the three CLIAs. Results: Within-laboratory precision of the four assays ranged from 2.1% to 9.4%, except the coefficient variation (CV) of one of the CLIAs, which exceeded 20.0% for samples with low sALD levels. sALD levels determined using LC-MS/MS were significantly lower than those determined using the other three CLIAs (p < 0.0001). Spearman's correlation coefficient of the four assays ranged from 0.745 to 0.950 (p < 0.0001). The Bland-Altman plot showed that the average bias (%) for the three CLIAs and LC-MS/MS ranged from −69.3 to −49.2. After recalibration, this correlation did not improve among the assays. However, the bias and bias percentage at the medical decision level improved between LC-MS/MS and DiaSorin® XL/iSYS. Conclusions: Significant inconsistencies between the results of CLIAs and LC-MS/MS indicate that different sALD measures cannot be used interchangeably. [ABSTRACT FROM AUTHOR]

Background: Thyroid hormone levels are essential for diagnosing and monitoring thyroid diseases. However, their reference intervals (RIs) in elderly Chinese individuals remain unclear. We aimed to identify factors affecting thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) levels using clinical "big data" to establish hormone level RIs for elderly Chinese individuals. Methods: We examined 6781, 6772, and 6524 subjects aged ≥65 years who underwent FT3, FT4, and TSH tests, respectively, at the Peking Union Medical College Hospital between September 1, 2013, and August 31, 2016. Hormones were measured using an automated immunoassay analyzer (ADVIA Centaur XP). RIs were established using the Clinical Laboratory Standards Institute document C28-A3 guidelines. Results: The median TSH was significantly higher in women than in men; the opposite was true for median FT3 and FT4 levels. No differences were observed in TSH or FT4 by age in either sex or overall; FT3 levels significantly decreased with age. Seasonal differences were observed in TSH and FT3 levels but not FT4 levels; the median TSH was the highest in winter and lowest in summer, whereas the median FT3 was the lowest in summer (albeit not significantly). RIs for TSH were 0.53–5.24 and 0.335–5.73 mIU/L for men and women, respectively; those for FT3 were 3.76–5.71, 3.60–5.42, and 3.36–5.27 pmol/L in 64- to 74-, 75- to 84-, and 85- to 96-year-old subjects, respectively. The RI for FT4 was 11.70–20.28 pmol/L. Conclusions: RIs for TSH in elderly individuals were sex specific, whereas those for FT3 were age specific. [ABSTRACT FROM AUTHOR]

Abstract Aldosterone (ALD) measurement plays a critical role in screening and diagnosis of primary aldosteronism. A variety of liquid chromatography tandem mass spectrometry (LC-MS/MS) methods for serum ALD have been developed. However, the few LC-MS/MS methods for 24 h urinary ALD that have been reported require tedious sample pretreatment procedure. This study aimed to establish a novel method for quantification of ALD in urine by LC-MS/MS. Urine samples from study participants were hydrolyzed and subjected to anion exchange solid phase extraction (SPE) followed by the detection of eluates by the negative electro-spray ionization and multiple reaction monitor modes. The established method was compared with two CLIA methods and 114 participants (M:39, F:75) were recruited to study the distribution of urinary ALD in an apparently healthy population. The pretreatment time was reduced to 4 h and the total run time for each sample was 4.5 min. The linearity of the method was in the range of 2–2000 pg/mL (r > 0.999); within laboratory coefficient variation (CV) and repeatability were both <5% and recovery was within 100% ± 10%. The established method showed good consistency with two CLIA methods with the correlation coefficients of 0.993(DiaSorin) and 0.980(Auto), respectively. In the 114 apparent healthy individuals, urinary ALD was 0.74–17.09 μg/24 h (P2.5–P97.5). The method showed an excellent performance of the method, prompting us to conclude that this method may be adopted in the clinic for routine testing and analysis of ALD in urine samples. Highlights • Much shorter time was used for the pretreatment of acid hydrolysis. • The LC-MS/MS method was simple, sensitive and precise. • The LC-MS/MS method showed good consistency with two currently used CLIA methods. • A reference range of aldosterone in urine was firstly reported in the Chinese population. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A simple ID-LC–MS/MS method for vitamins A and E in serum and amniotic fluid was developed. • The ID-LC–MS/MS method was precise and sensitive. • None of the 65 apparently healthy volunteers developed vitamin A or E deficiency. • Significant correlation between amniotic fluid and serum vitamin A was observed. Abstract Accurate and simple measurements of vitamins A(all-trans retinol) and E(α-tocopherol) are essential for ensuring the appropriate supplementation and diagnosis of diseases related to vitamin A or E deficiency. High-performance liquid chromatography is a widely used method; however, few studies have reported an isotope dilution-liquid chromatography tandem mass spectrometry method(ID-LC–MS/MS) for detecting vitamins A and E in serum, let alone amniotic fluid. Here, we developed and validated an accurate and precise measurement procedure based on ID-LC–MS/MS for detecting vitamins A and E in serum and amniotic fluid. In this method, only 50 μL of serum/amniotic fluid was used. After simple protein precipitation and extraction, all-trans retinol and α-tocopherol were analyzed by ID-LC–MS/MS using positive electrospray ionization in multiple reaction monitoring mode. Vitamins A and E status was evaluated using the validated method in 65 apparently healthy volunteers and 58 pregnant women in the second trimester. The within-run and total coefficients of variation(CVs) of all-trans retinol were 2.8%–3.9% and 4.7%–6.0%, respectively, in serum; and 5.0%–7.3% and 5.4%–7.4%, respectively, in amniotic fluid ; and the values for α-tocopherol were 3.2%∼4.3% and 3.3% ∼ 4.9% in serum and 6.2%–7.1% and 8.0%–9.1% in amniotic fluid. The accuracy bias of the ID-LC–MS/MS method was less than 5.0% for both all-trans retinol and α-tocopherol. Mean levels of all-trans retinol and α-tocopherol in the 65 apparently healthy volunteers were 0.504±0.126 mg/L and 12.038±2.501 mg/L, respectively. A significant positive correlation was observed between serum and amniotic fluid all-trans retinol (r=0.277, P=0.035) in the pregnant women in the second trimester, while no correlation with α-tocopherol (P=0.290). None of the volunteers developed vitamin A or E deficiency. In conclusion, an ID-LC–MS/MS method for measuring both serum and amniotic fluid all-trans retinol and α-tocopherol levels was developed. This method is accurate and simple, and can be used clinically to monitor vitamins A and E status. [ABSTRACT FROM AUTHOR]

Background: Arterial spin labeling (ASL) based-noncontrast-enhanced 4D MR angiography (NCE 4D MRA) shows potential in characterizing cerebrovascular hemodynamics in cerebrovascular disorders. Ultrahigh-field theoretically benefits ASL signal with increased inherent signal-to-noise ratio (SNR) and prolonged blood T1 , which may provide improved delineation of vasculature in 4D MRA.Purpose: To investigate the feasibility of NCE 4D MRA using 3D Cartesian trajectory and stack-of-stars (SOS) golden angle radial trajectory at 7T.Study Type: A prospective study.Subjects: Six normal volunteers and eight patients with arteriovenous malformation (AVM).Field Strength/sequence: NCE 4D MRA with Cartesian and radial trajectories were performed at 3T and 7T.Assessment: Subjective image quality of 4D MRA was evaluated using a 4-point scale by two experienced neuroradiologists. The characterization of AVM components with 4D MRA and DSA was also graded using the Spetzler-Martin grading scale.Statistical Tests: Cohen's kappa coefficient was calculated to evaluate the agreement between two readers within each 4D MRA technique (Cartesian and Radial). A Wilcoxon signed-rank test was performed to compare the subjective image quality scores of 4D MRA between Cartesian and radial trajectories, and between 7T and 3T, respectively.Results: Good-to-excellent image quality was achieved in 4D MRA with both Cartesian (3.83 ± 0.41) and radial (3.42 ± 0.49) acquisitions in healthy volunteers at 7T. However, markedly reduced scan time was needed with radial acquisition. 4D MRA at 7T (3.31 ± 0.59) shows better delineation of AVM lesion features, especially the vein drainage, compared with that of 3T (2.83 ± 0.75), although no statistical significance was achieved (P = 0.180).Data Conclusion: The feasibility of ASL based 4D MRA at 7T with Cartesian and SOS golden angle radial acquisition was demonstrated. The clinical evaluation of 4D MRA in AVMs between 3T and 7T suggested 7T 4D MRA images acquired with radial acquisition demonstrate excellent delineation of AVM features, especially the draining veins.Level Of Evidence: 2 Technical Efficacy Stage 2 J. Magn. Reson. Imaging 2017. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop and evaluate a scoring system for assessing reperfusion status based on arterial spin labeled (ASL) perfusion MRI in acute ischemic stroke (AIS) patients receiving thrombolysis and/or endovascular treatment. Pseudo-continuous ASL with background suppressed 3D GRASE was acquired along with DWI in 90 patients within 24 h post-treatment. An automatic reperfusion scoring system (auto-RPS) was devised based on the Alberta Stroke Program Early CT Score (ASPECTS) template, and compared with manual RPS and DWI-ASPECTS. TICI (thrombolysis in cerebral infarction) scores were graded in 48 patients who received endovascular treatment. Favorable outcomes were defined by a modified Rankin Scale score of 0–2 at three months. Auto-RPS was positively correlated with DWI-ASPECTS (ρ = 0.6, P < 0.001) and was on average 1 point lower than DWI-ASPECTS (P < 0.001). The area under the receiver operating characteristic curve for discriminating poor functional outcome (n = 90) was 0.75 (95% CI, 0.64–0.86) for manual RPS, 0.85 (95% CI, 0.76–0.94) for auto-RPS, and 0.81 (95% CI, 0.71–0.90) for DWI-ASPECTS. Multiple logistic regression analysis in the TICI-graded patients (n = 48) showed that auto-RPS is highly associated with functional outcome (OR = 25.2, 95% CI 4.02–496, P < 0.01). Post treatment auto-RPS within 24 h provides a useful tool to predict functional outcome in AIS patients. [ABSTRACT FROM AUTHOR]

Background: The demand for vitamin D testing is increasing in China. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) immunoassay is specific and accurate but requires expensive equipment, experienced operators, and complicated pretreatment of serum. Automated immunoassays are simple and convenient but only determine total 25-hydroxyvitamin D (25OHD). The objective of this study was to quantify 25OHD2 and 25OHD3 in patients to assist clinical physicians and laboratory directors in choosing the most appropriate method to determine 25OHD. Methods: Vitamin D testing was conducted for 23,695 patients in Peking Union Medical College Hospital from May 2015 to January 2017. Using this large data set, the prevalence and levels of 25OHD2 were analyzed. LC-MS/MS was used to separately determine 25OHD2 and 25OHD3. Results: 25OHD2 (≥2.5 ng/mL) was detected in 16.4% (3877/23,695) of patients. Males had a significantly lower incidence of detectable 25OHD2 (p < 0.01); 1077 (13.9%) samples contained detectable 25OHD2 (median: 3.7 ng/mL; 2.5%-97.5%: 2.5-17.2 ng/mL). For females, 2800 (17.5%) samples contained detectable 25OHD2 (median: 4.0 ng/mL; range: 2.5-20.6 ng/mL). Of the 3877 patients with detectable 25OHD2, males had a significantly higher level of 25OHD3 (p < 0.01). There was no significant difference in total 25OHD. The proportion of 25OHD2 in total 25OHD was 1.3%-100%; 87.5% (3391/3877) of the samples contained <10 ng/mL 25OHD2. 25OHD2 negatively correlated with 25OHD3 (r = -0.197, p < 0.01) and positively correlated with total 25OHD (r = 0.217, p < 0.01). Conclusions: Prevalence of 25OHD2 in patients tested for vitamin D is relatively high in China. 25OHD2 is significantly negatively correlated with 25OHD3. [ABSTRACT FROM AUTHOR]

Previous research has proven that disruption of either the CCR5 or the CXCR4 gene confers resistance to R5-tropic or X4-tropic human immunodeficiency virus type 1 (HIV-1) infection, respectively. However, the urgent need to ablate both of the co-receptors in individual post-thymic CD4+ T cells for dual protection remains. This study ablated the CCR5 and CXCR4 genes in human CD4+ cell lines and primary CD4+ T cells simultaneously using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9, a well-developed, highly efficient genetic engineering tool. The efficiency of gene modification is as high as 55% for CCR5 and 36% for CXCR4 in CD4+ cell lines through infection of a single lentiviral vector (LV-X4R5), which were markedly protected from both HIV-1NL4-3 (X4-using strain) and HIV-1YU-2 (R5-using strain) infection. Importantly, approximately 9% of the modified GHOST (3) CXCR4+CCR5+ cells harbor four bi-allelic gene disruptions in both the CXCR4 and CCR5 loci. Moreover, co-delivery of two single-guide RNAs loaded with Cas9: ribonucleoprotein (sgX4&R5 Cas9RNP) disrupted >12% of CCR5 and 10% of CXCR4 in primary human CD4+ T cells, which were rendered resistant to HIV-1NL4-3 and HIV-1YU-2 in vitro. Further, the modified cells do not show discernible mutagenesis in top-ranked off-target genes by the Surveyor assay and Sanger sequencing analysis. The results demonstrate the safety and efficacy of CRISPR/Cas9 in multiplex gene modification on peripherally circulating CD4+ T cells, which may promote a functional cure for HIV-1 infection. [ABSTRACT FROM AUTHOR]

• We overviewed fat-soluble vitamin deficiencies and their related diseases. • We compared liquid chromatography-tandem mass spectrometry with immunoassay for the determination of fat-soluble vitamins. • We overviewed the applications and advantages of liquid chromatography-tandem mass spectrometry methods for fat-soluble vitamin measurement. • We summarized common fat-soluble vitamin metabolites and the key analytical parameters of reported LC-MS/MS methods. Fat-soluble vitamins, including vitamins A, D, E, and K, are essential for maintaining normal body function and metabolism. Fat-soluble vitamin deficiency may lead to bone diseases, anemia, bleeding, xerophthalmia, etc. Early detection and timely interventions are significant for preventing vitamin deficiency-related diseases. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is developing into a potent instrument for the precise detection of fat-soluble vitamins due to its high sensitivity, high specificity, and high resolution. [ABSTRACT FROM AUTHOR]