Ning Dong

Neuroprotective Effects of Erythropoietin in Patients with Carbon Monoxide Poisoning

The purpose of this study was to evaluate the efficacy of erythropoietin (EPO) for treating patients with carbon monoxide (CO) poisoning. We conducted a randomized, prospective study of 103 patients with CO poisoning in two groups: an EPO group (n = 54; patients received EPO) and a placebo group (n = 49; patients received normal saline). The study endpoints were the functional outcome at day 30 (the Barthel index and neurologic sequelae), National Institutes of Health Stroke Scale (NIHSS) score, and the levels of S‐100β. At 18 days, the NIHSS score improved significantly and S‐100β levels significantly decreased in patients in the EPO group. At 30 days, patients in the EPO group had a superior Barthel index and fewer patients had delayed neurologic sequelae (DNS). This study demonstrated that early administration of EPO to patients with CO poisoning improved neurological outcomes and reduced the incidence of DNS.

LC-ESI-MS/MS analysis and pharmacokinetics of heterophyllin B, a cyclic octapeptide from Pseudostellaria heterophylla in rat plasma

Heterophyllin B (HB) is a cyclic octapeptide isolated from Pseudostellaria heterophylla. HB is used as the quality control index for evaluating P. heterophylla in the Chinese Pharmacopoeia. A rapid and sensitive LC-ESI-MS/MS method was developed and validated for the analysis of HB in rat plasma. Sample preparation consisted of a solid-phase extraction step for the removal of interference and preconcentration of the target analyte HB and the internal standard N-acetylcysteine before chromatographic analysis by MS/MS detection. The separation of HB and N-acetylcysteine was performed using a Hypersil GOLD™ C18 column and a mixture of methanol-water (60:40, v/v) containing 10 mmol/L ammonium formate and 0.1% formic acid as the mobile phase. The determination step was optimized in the selected reaction monitoring mode for the highly selective and sensitive quantitation of HB in rat plasma. Intra- and inter-assay precision (as relative standard deviation) was ≤9.1%, and accuracy was between 92.6 and 102.7%. The validated method was successfully applied to quantify HB concentrations up to 7 h after tail intravenous injections of 2.08, 4.16 and 8.32 mg/kg HB in rats. The LC-MS/MS method identified the relevant pharmacokinetic parameters of HB and its studied analog.

Elevated serum ubiquitin C-terminal hydrolase-L1 levels in patients with carbon monoxide poisoning.

OBJECTIVE Ubiquitin C-terminal hydrolase-L1 (UCH-L1) has been established as a reliable and potential biomarker of neuronal damage after acute neurologic insults, such as ischemic stroke, subarachnoid hemorrhage, and traumatic brain injury. However, the effect of serum UCH-L1 levels has not been investigated in carbon monoxide (CO)-poisoned patients. The aim of the present study was to evaluate whether serum UCH-L1 levels are a reliable marker of brain damage and the association of UCH-L1 with outcome. DESIGN AND METHODS This case-control study enrolled 46 CO-poisoned subjects and 30 controls. Using an enzyme-linked immunosorbent assay (ELISA) kit, we studied the temporal profile of serum UCH-L1 levels at 6, 12, 24 and 48 h after acute CO poisoning. Poisoning severity was assessed using the Glasgow Coma Scale (GCS) score. Long-term outcome was assessed using the Glasgow Outcome Scale (GOS) at 6 months after poisoning. RESULTS Compared with controls, CO-poisoned patients had significantly elevated serum levels of UCH-L1 at each time point after poisoning. There were significantly higher levels of UCH-L1 in CO-poisoned patients with a lower GCS score as well as in those with a poor 6-month outcome dichotomized GOS. CONCLUSIONS Serum levels of UCH-L1 appear to have potential clinical utility in providing valuable information about poisoning severity and outcome after CO poisoning.

Plasma copeptin as a predictor of intoxication severity and delayed neurological sequelae in acute carbon monoxide poisoning.

The present study was designed to assess the usefulness of measuring plasma levels of copeptin (a peptide co-released with the hypothalamic stress hormone vasopressin) as a biomarker for the severity of carbon monoxide (CO) poisoning and for predicting delayed neurological sequelae (DNS). Seventy-two patients with CO poisoning and 72 sex and age matched healthy individuals were recruited. Plasma copeptin levels were measured on admission from CO poisoning patients and for healthy individuals at study entry by using a sandwich immunoassay. The CO poisoning patients were divided into two groups according to severity (unconscious and conscious) and occurrence of DNS. The mean plasma copeptin levels (52.5±18.5 pmol/L) in the unconscious group were significantly higher than in the conscious group (26.3±12.7 pmol/L) (P<0.001). Plasma copeptin levels of more than 39.0 pmol/L detected CO poisoning with severe neurological symptoms e.g. unconsciousness (sensitivity 84.6% and specificity 81.4%). The plasma copeptin levels were higher in patients with DNS compared to patients without DNS (52.2±20.6 pmol/L vs. 27.9±14.8 pmol/L, P<0.001). Plasma copeptin levels higher than 40.5 pmol/L predicted the development of DNS (sensitivity 77.8%, specificity 82.1%). Plasma copeptin levels were identified as an independent predictor for intoxication severity [odds ratio (OR) 1.261, 95% confidence interval (CI) 1.112-1.638, P=0.002] and DNS (OR 1.313, 95% CI 1.106-1.859, P=0.001). Thus, plasma copeptin levels independently related to intoxication severity and were identified as a novel biomarker for predicting DNS after acute CO poisoning.

Quantification of taraxasterol in rat plasma by LC/MS/MS: application to a pharmacokinetic study

Taraxasterol, a pentacyclic triterpene from Taraxacum officinale, is one of the main active constituents of the herb. This study developed and validated a highly selective and sensitive liquid chromatography/tandem mass spectrometry for the determination of taraxasterol in rat plasma over the range of 9.0-5000 ng/mL. Chromatographic separation was achieved on a C18 (4.6 × 50 mm, 5.0 µm) column with methanol-isopropanol-water-formic acid (80:10:10:0.1, v/v/v/v) as mobile phase with an isocratic elution. The flow rate was 0.7 mL/min. After adding cucurbitacin IIa as an internal standard (IS), liquid-liquid extraction was used for sample preparation using ethyl acetate. The atmospheric pressure chemical ionization source was applied and operated in positive ion mode. Selected reaction monitoring mode was used for the quantification of transition ions m/z 409.4 → 137.1 for taraxasterol and m/z 503.4 → 113.1 for IS. The mean recoveries of taraxasterol in rat plasma ranged from 85.3 to 87.2%. The matrix effects for taraxasterol were between 98.5 and 104.0%. Intra- and inter-day precision were both <11.8%, and the accuracy of the method ranged from -7.0 to 12.9%. The method was successfully applied to a pharmacokinetic study of taraxasterol after oral administration of 7.75, 15.5 and 31.0 mg/kg in rats.

Quantitative Determination and Pharmacokinetic Study of Aurantio-Obtusin in Rat Plasma by Liquid Chromatography-Mass Spectrometry

A simple and sensitive liquid chromatography-tandem mass spectrometric method was developed and validated to measure aurantio-obtusin content in rat plasma using rhein as internal standard (IS). The analytes were extracted from plasma by a simple liquid-liquid extraction technique using ethyl acetate as extraction solvent. Chromatographic separation was performed on a Zorbax XDB-C18 column (50 mm × 4.6 mm, 2.1 µm particle size) using the mobile phase consisting of methanol-water (70 : 30, v/v). The detection was achieved by negative ion electrospray ionization in selected reaction monitoring mode, monitoring the transitions m/z 329.1 → 299.2 and m/z 283.1 → 183.0 for aurantio-obtusin and IS, respectively. The assay was linear over a concentration range of 4-4,000 ng/mL with a lower limit of quantification of 4.00 ng/mL for aurantio-obtusin. The intra- and inter-day precision was <6.8%, and the accuracy values were between -1.7 and 7.1%. The validated method was successfully applied to the pharmacokinetics of aurantio-obtusin following intravenous administrations to rats.

Increased Dickkopf-1 expression is correlated with poisoning severity in carbon monoxide-poisoned humans and rats

Abstract Context: Carbon monoxide (CO) poisoning results in neuronal injury. The expression of Dickkopf-1 (DKK-1) has not been investigated previously after CO poisoning. Objective: The current study aimed to investigate the DKK-1 expression levels in humans and rats with acute CO poisoning and to analyze their correlation with poisoning severity. Materials and methods: We measured serum DKK-1 levels in patients with acute CO poisoning (n = 94) and in healthy controls (n = 90). On admission, a poisoning severity score (PSS) was determined for each patient. In addition, 36 male Sprague–Dawley rats were randomly assigned into three groups: (a) Sham group, (b) Low CO group and (c) High CO group. At 2 h after CO poisoning, DKK-1 expression and histopathological damage in the hippocampal tissues were measured. Results: Serum DKK-1 levels were significantly higher in the acute CO-poisoned patients, compared to the healthy controls. Serum DKK-1 levels were significantly higher in the CO-poisoned patients with a lower PSS. In rats, CO poisoning induced significant upregulation of the gene and protein expression of DKK-1 in hippocampal tissues. Moreover, there was a positive correlation between DKK-1 levels and the degree of damage in the hippocampal tissues. Discussion: DKK-1 induction in neurons after CO poisoning causes further neuronal injury. The severity of acute CO poisoning in rat models is associated with elevated serum DKK-1 levels and its upregulation in the brain tissue. Conclusion: DKK-1 appears to have potential utility in providing valuable information for determining the severity and damage of CO poisoning.

Prognostic Value of Plasma Visfatin Level for Chinese Patients with Severe Carbon Monoxide Poisoning.

BACKGROUND This prospective observatory study was designed to investigate whether plasma visfatin might serve as a marker of prognosis in patients with severe carbon monoxide (CO) poisoning. METHODS A total of 52 consecutive patients with severe CO poisoning and 52 gender- and age- matched healthy subjects were enrolled in the study, and their plasma visfatin levels were determined using an enzyme-linked immunosorbent assay. The clinical outcomes, including in-hospital mortality, 6-month mortality, and poor outcome (Glasgow Outcome Scale score of 1 - 3), were recorded. RESULTS Plasma visfatin levels were statistically significantly higher in patients than in healthy controls (97.4 ± 28.0 ng/mL vs. 12.1 ± 3.7 ng/mL; p < 0.001). Multivariate logistic regression analysis showed that plasma visfatin level was an independent prognostic predictor of in-hospital mortality [odds ratio (OR), 1.214; 95% confidence interval (CI), 1.103 - 1.425; p < 0.001], 6-month mortality (OR, 1.269; 95% CI, 1.085 - 1.534; p < 0.001), and 6-month poor outcome (OR, 1.302; 95% CI, 1.023 - 1.520; p < 0.001). Moreover, receiver operating characteristic curves showed that plasma visfatin level had high predictive value for in-hospital mortality [area under curve (AUC), 0.931; 95% CI, 0.832 - 1.000], 6-month mortality (AUC, 0.894; 95% CI, 0.801 - 0.987), and 6-month poor outcome (AUC, 0.886; 95% CI, 0.796 - 0.977). CONCLUSIONS Plasma visfatin levels are significantly higher in patients with severe CO poisoning and could be a useful biomarker to predict short- and long-term clinical outcome after severe CO poisoning.