QT-Interval Prolongation Associated with Supratherapeutic Guanfacine Concentration: A Case Report.

INTRODUCTION: Guanfacine, an alpha-2 adrenergic agonist, is used to treat attention deficit hyperactivity disorder (ADHD). Although cardiovascular effects including hypotension and bradycardia are common adverse effects of guanfacine, the effect of guanfacine on QT intervals remains unclear. The association between the serum concentration of guanfacine and its toxicity has also not been fully investigated. CASE REPORT: This is a case of a 21-year-old woman with ADHD who developed repeated presyncope 1 day before admission. She was taking 3 mg of extended-release guanfacine and 50 mg of sertraline. On admission, she had bradycardia and hypotension. An electrocardiogram (ECG) showed a QT interval of 0.68 s and a QTcF interval of 0.648 s. The QT intervals were manually measured and corrected by the Fridericia formula (QTcF = QT/RR1/3). Although she denied taking an overdose of guanfacine and other drugs, we suspected guanfacine toxicity. The serum guanfacine concentration was 13.0 ng/mL on admission and decreased to 3.2 ng/mL on day 1 and 0.4 ng/mL on day 2. Changes in QTcF intervals and her vital signs correlated with serum guanfacine concentrations. CONCLUSION: Supratherapeutic serum guanfacine concentrations may induce QT prolongation.

Left Stellate Ganglion Blockade for Refractory Ventricular Arrhythmias With Aconitine Poisoning: A Case Report.

Aconitine poisoning causes refractory ventricular arrhythmias (VAs). In a 20-year-old man, VAs of unknown etiology did not respond to drugs and electrical defibrillation. However, left stellate ganglion blockade (SGB) dramatically decreased arrhythmias without complications. At a later date, we found that refractory VAs were caused by aconitine poisoning. Left SGB is effective for treating refractory VAs with aconitine poisoning and can be easily performed with few complications for VAs of unknown etiology even if patients are receiving anticoagulant therapy. Also, left SGB can be performed to diagnose refractory VAs.

Detection of lisdexamfetamine and its metabolite d-amphetamine in urine and gastric contents collected from a cadaver at forensic autopsy.

PURPOSE: Lisdexamfetamine (LDX), which is used for the treatment of attention-deficit/hyperactivity disorder and narcolepsy, is composed of L-lysine attached to dextroamphetamine (d-amphetamine). In this article, we report a forensic autopsy case in which prescription drugs were unknown at autopsy. While amphetamine was detected, methamphetamine could not be detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in any of samples collected. Thus, we aimed to quantify LDX concentrations in autopsy samples and to prove that the amphetamine detected in this case was due to metabolized LDX. METHODS: Femoral vein blood, cardiac whole blood, urine, and gastric content samples were taken at autopsy for toxicological analysis. Qualitative and quantitative analyses were performed using LC-MS/MS. In addition, optical isomer separation for the amphetamine detected was conducted. The stability of LDX in whole blood and urine was also examined at three different temperatures. RESULTS: The concentrations of LDX were < 4.00, 30.9, and 4.42 ng/mL in whole blood, urine, and gastric content samples, respectively. The concentrations of amphetamine were 329, 510, 2970, and 915 ng/mL in femoral vein blood, heart whole blood, urine, and gastric contents, respectively. The amphetamine detected in this case was identified to be only d-amphetamine by optical isomer separation. The d-amphetamine detected was considered to be derived from LDX. Stability experiments revealed that LDX in whole blood decreased at ambient temperature. CONCLUSIONS: The results in the present case report may be useful in interpreting whether or not the amphetamine detected in a cadaver is a metabolite of LDX.

Unexpectedly Prolonged Serotonin Syndrome and Fatal Complications Following a Massive Overdose of Paroxetine Controlled-Release.

Symptoms caused by a selective serotonin reuptake inhibitor (SSRI) overdose are often mild and can be managed with supportive care and close monitoring, even when complicated by serotonin syndrome. There are limited pharmacokinetic data regarding massive overdoses of paroxetine, and the severity of an SSRI overdose is likely to be underestimated. We describe a fatal case of severe serotonin syndrome and acute respiratory distress syndrome (ARDS) following an overdose of controlled-release paroxetine. A 53-year-old male with depression presented with altered consciousness. He had ingested controlled-release paroxetine along with other medications. On arrival, he had ocular flutter and myoclonus, and blood examinations revealed acute kidney injury and rhabdomyolysis, which suggested serotonin syndrome. Computed tomography (CT) showed pharmacobezoars in the esophagus and stomach. Symptoms of serotonin syndrome and hypotension persisted despite administration of high doses of vasopressors with endotracheal intubation. We performed endoscopic decontamination to remove pharmacobezoars from the stomach. Finally, he developed severe ARDS and died due to respiratory failure on day 23. Sequential serum concentrations of paroxetine were 5.38 µg/mL at admission and 3.21 µg/mL on day 7, both above lethal levels. This case highlights the potential for fatal complications and prolonged toxicity in the case of a massive overdose of controlled-release paroxetine. We should recognize that such an overdose may be life-threatening and should consider aggressive interventions including endoscopic decontamination. A better understanding of the pharmacokinetics of a massive SSRI overdose would be helpful for optimal management.

Comparison of serum and whole blood concentrations in quetiapine overdose cases.

This study aimed to compare whole blood and serum concentrations of quetiapine in acute poisoning cases. Authentic whole blood and respective serum samples were routinely collected from patients diagnosed with blood poisoning at our University Hospital. Accordingly, whole blood and serum paired samples from nine patients (one male and eight female patients) were analyzed for quetiapine using liquid chromatography-mass spectrometry (LC-MS). Quetiapine concentrations in whole blood and serum samples ranged widely from 5.4 to 2780 ng/mL and 9.9 to 2500 ng/mL, respectively. The whole blood/serum concentration ratio was 0.5-1.1 and increased together with an increase in whole blood and serum quetiapine concentrations. The ratio was reversed at around 2500 ng/mL to > 1. Our findings suggest that whole blood concentrations are more useful than serum concentrations in diagnosing quetiapine poisonings.

Four cases of cytokine storm after COVID-19 vaccination: Case report.

The global coronavirus disease 2019 (COVID-19) pandemic has led to the rapid development of vaccines against this disease. Despite the success of the international vaccination program, adverse events following vaccination, and the mechanisms behind them, remain poorly understood. Here we present four cases of death following receipt of a second dose of COVID-19 vaccine, with no obvious cause identified at autopsy. Using RNA sequencing, we identified genes that were differentially expressed between our post-vaccination cases and a control group that died of blood loss and strangulation. Three hundred and ninety genes were found to be upregulated and 115 genes were downregulated in post-vaccination cases compared with controls. Importantly, genes involved in neutrophil degranulation and cytokine signaling were upregulated. Our results suggest that immune dysregulation occurred following vaccination. Careful observation and care may be necessary if an abnormally high fever exceeding 40°C occurs after vaccination, even with antipyretic drugs.

A method for determining valproic acid in human whole blood and urine via gas chromatography-mass spectrometry and small-scale inter-laboratory trial.

A simple and cost-effective method for analyzing valproic acid (VPA) in biological samples was developed. VPA was extracted in methyl tertiary-butyl ether (MTBE) and derivatized using trimethylsilyldiazomethane. The MTBE extract was analyzed by gas chromatography-mass spectrometry (GC-MS). The extraction recovery in human whole blood and urine was over 90 %, with good linearity in the range of 1.0 to 250 µg/mL of VPA. The RSD for 2.0, 20, and 200 µg/mL VPA in whole blood ranged from 0.9 to 4.7 % for intra-day and 1.5 to 5.9 % for inter-day. The RSD for 2.0, 20, and 200 µg/mL VPA in urine ranged from 1.9 to 2.6 % for intra-day and 1.2 to 2.9 % for inter-day. As a preliminary cross-validation study, a cross-check was conducted using blinded concentration samples. The results demonstrated that the assay data of the two laboratories were comparable.

Simple and simultaneous quantification of cyanide, ethanol, and 1-propanol in blood by headspace GC-MS/NPD with Deans switch dual detector system.

Cyanide is a powerful and rapidly acting poison. In Japan, cyanide poisoning is rare, and regular cyanide testing can be costly and time consuming. In contrast, alcohol analysis is routinely performed in most forensic laboratories. In this study, we attempted to develop a method for the simultaneous quantification of cyanide and alcohols in blood using headspace gas chromatography (HS-GC). As nitrogen-phosphorus detection (NPD) is more sensitive to hydrogen cyanide than mass spectrometry (MS), a Deans switch was used to switch the detectors during a single run. The separation provided by three analytical columns, PoraBOND Q, CP-Sil 5 CB, and HP-INNOWax, was investigated, and PoraBOND Q was selected. The use of HS-GC-MS/NPD with a Deans switch enabled the simple and simultaneous quantification of cyanide, ethanol, and 1-propanol. Eighteen other volatile compounds were detected in the SIM/scan mode of the MS.

BIMP affects tubulin structure and causes abnormalities in cell division.

Although organophosphorus agents are used worldwide as pesticides, there have been many reports of pesticide poisoning. Nerve agents are organophosphorus agents that interfere with neurotransmission and have been used as chemical weapons in wars. These agents mainly irreversibly inhibit the action of acetylcholinesterase, an enzyme that breaks down acetylcholine, a neurotransmitter, and are believed to cause acute symptoms of poisoning. However, in recent years, the presence of subacute, delayed toxicity independent of acetylcholinesterase inhibition has been reported for some organophosphorus agents. We analyzed the subacute and delayed toxicity of bis(isopropylmethyl)phosphonate (BIMP), which has the same phosphonate group as sarin. BIMP rounded out the morphology of the cells and reduced the proportion of cells in the G1 phase of the cell cycle over time. No DNA damage was observed, suggesting that BIMP may affect cell division.

Neural dysfunctions following experimental permanent occlusions of bilateral common carotid arteries cause an increase of rat voluntary alcohol drinking behavior.

We have previously reported that ischemic animal models treated with a respiratory inhibitor, rotenon, show an increased voluntary alcohol intake. Although it is clear that ischemic brain, as a result of reduced-blood flow, shows pathological events and/or neuro-degenerations apparently, little is known of causal relationship between the mechanism of neural dysfunction and voluntary alcohol consumption. Authors have investigated effects of permanent two-vessel occlusion (p2VO) on rat voluntary alcohol drinking behavior. In first experiment the p2VO-treated rats showed an increase of voluntary alcohol drinking behavior, as compared with sham controls. Using brain microdialysis technique, increases of only nucleus accumbens (ACC) dopamine (DA) releases were suppressed in the p2VO-treated rats significantly, following the high K+ (40 mM) perfusion through the microdialysis probe membrane. Alcohol (200 mM) perfusion-induced DA and serotonin (5-HT) releases in the ACC of the p2VO-treated rats were suppressed significantly in the second experiment, as compared with the sham-treated rats. In third experiment p2VO-treated rats showed significant decreases of the contents of DA, not 5-HT, in the ACC, caudate-putamen (C/P), ventral tegmental area-substantia nigra (VT/SN) and lateral hypothalamus (LH). Dopaminergic neurons in the ACC showed more functional vulnerability against the p2VO treatments, as compared with the serotonergic neurons. An increase of alcohol intake in the p2VO-treated rats means the compensation for the neural degeneration of the dopaminergic system in the ACC consisted brain rewarding system. It was likely suggested that neural disturbance of higher functions involved with incomplete global brain ischemia leads the risk of an abnormal alcohol drinking in human.

Simple and reliable method to simultaneously determine urinary 1- and 2-naphthol using in situ derivatization and gas chromatography-mass spectrometry for biological monitoring of naphthalene exposure in occupational health practice.

OBJECTIVES: The aim of this study was to develop and validate a simple and reliable gas chromatography-mass spectrometry (GC-MS) method to simultaneously determine urinary 1-naphthol (1-NAP) and 2-naphthol (2-NAP) for biological monitoring of occupational exposure to naphthalene. METHODS: NAPs were derivatized in situ with acetic anhydride after enzymatic hydrolysis, extracted with n-hexane, and analyzed using GC-MS. Validation of the proposed method was conducted in accordance with US Food and Drug Administration guidance. A final validation was performed by analyzing a ClinChek® -Control for phenolic compounds. RESULTS: The linearity of calibration curves was indicated by a high correlation coefficient (>0.999) in the concentration range 1-100 µg/L for each NAP. The limits of detection and quantification for each NAP were 0.30 and 1.00 µg/L, respectively. The recovery was 90.8%-98.1%. The intraday and interday accuracies, expressed as the deviation from the nominal value, were 92.2%-99.9% and 93.4%-99.9%, respectively. The intraday and interday precision, expressed as the relative standard deviation, was 0.3%-3.9% and 0.4%-4.1%, respectively. The ClinChek® values obtained using our method were sufficiently accurate. CONCLUSIONS: The proposed method is simple, reliable, and appropriate for routine analyses, and is useful for biological monitoring of naphthalene exposure in occupational health practice.

Assessment of Concentrations of Four Phenothiazine Antipsychotics in Serum and Whole Blood Using Different Diatomaceous Earth-based Solid-phase Columns: A Comparative Analysis.

This study attempted to determine the phenothiazine antipsychotics concentration in serum and whole blood samples using various diatomaceous earth-based solid-phase columns and elution solvents and subsequently evaluate their efficiency. Phenothiazine antipsychotics concentrations of 5 - 2000 ng/mL were extracted from serum and whole blood using each column. All compounds were analyzed using liquid chromatography-tandem mass spectrometry. Phenothiazine antipsychotics extraction in serum and whole blood using diatomaceous earth-based solid-phase columns seemed to have an affinity with the elution solvent.

Direct methyl esterification with 2,2-dimethoxypropane for the simultaneous determination of urinary metabolites of toluene, xylene, styrene, and ethylbenzene by gas chromatography-mass spectrometry.

OBJECTIVES: The purpose of this study was to develop a simple and accurate gas chromatography-mass spectrometry (GC-MS) method for simultaneous determination of four urinary metabolites from four organic solvents, that is, hippuric acid (HA) from toluene, methylhippuric acid (MHA) from xylene, and mandelic acid (MA) and phenylglyoxylic acid (PGA) from styrene or ethylbenzene for biological monitoring. METHODS: The four metabolites were directly methyl-esterified with 2,2-dimethoxypropane and analyzed using GC-MS. The proposed method was validated according to the US Food and Drug Administration guidance. The accuracy of the proposed method was confirmed by analyzing a ClinChek® -Control for occupational medicine (RECIPE Chemicals +Instruments GmbH). RESULTS: Calibration curves showed linearity in the concentration range of 10-1000 mg/L for each metabolite, with correlation coefficients >0.999. For each metabolite, the limits of detection and quantification were 3 mg/L and 10 mg/L, respectively. The recovery was 93%-117%, intraday accuracy, expressed as the deviation from the nominal value, was 92.7%-103.0%, and intraday precision, expressed as the relative standard deviation (RSD), was 1.3%-4.7%. Interday accuracy and precision were 93.4%-104.0% and 1.2%-9.5%, respectively. The analytical values of ClinChek obtained using the proposed method were sufficiently accurate. CONCLUSIONS: The proposed method is a simple and accurate which is suitable for routine analyses that could be used for biological monitoring of occupational exposure to four organic solvents.

Optimization and application of octadecyl-modified monolithic silica for solid-phase extraction of drugs in whole blood samples.

Monolithic silica in MonoSpin for solid-phase extraction of drugs from whole blood samples was developed to facilitate high-throughput analysis. Monolithic silica of various pore sizes and octadecyl contents were synthesized, and their effects on recovery rates were evaluated. The silica monolith M18-200 (20µm through-pore size, 10.4nm mesopore size, and 17.3% carbon content) achieved the best recovery of the target analytes in whole blood samples. The extraction proceeded with centrifugal force at 1000rpm for 2min, and the eluate was directly injected into the liquid chromatography-mass spectrometry system without any tedious steps such as evaporation of extraction solvents. Under the optimized condition, low detection limits of 0.5-2.0ngmL-1 and calibration ranges up to 1000ngmL-1 were obtained. The recoveries of the target drugs in the whole blood were 76-108% with relative standard deviation of less than 14.3%. These results indicate that the developed method based on monolithic silica is convenient, highly efficient, and applicable for detecting drugs in whole blood samples.

Detection of synthetic cannabinoids using GC-EI-MS, positive GC-CI-MS, and negative GC-CI-MS.

Recently, various synthetic cannabinoid (SC) compounds that have been slightly modified at the functional groups have been identified in Japan. However, the structural elucidation of these new compounds using conventional approaches such as gas chromatography-electron impact-mass spectrometry (GC-EI-MS) is difficult. As such, indole and indazole SCs were scanned using GC-MS-EI, positive GC-chemical ionization (CI)-MS, and negative GC-chemical ionization-MS, allowing for efficient structural elucidation of unknown SC compounds. Pure substances have been employed for the study.

The sarin-like organophosphorus agent bis(isopropyl methyl)phosphonate induces ER stress in human astrocytoma cells.

Organophosphorus (OP) compounds such as sarin are toxic agents that irreversibly inhibit the enzyme acetylcholinesterase. A recent study showed that OP compounds also have multiple toxicity mechanisms, and another suggested that endoplasmic reticulum (ER) dysfunction contributes to OP toxicity. However, the signaling pathway and mechanisms involved are poorly understood. We examined whether the sarin-like OP agent bis(isopropyl methyl)phosphonate (BIMP), which exhibits toxicity similar to that of sarin, induced ER stress in human astrocytoma CCF-STTG1 cells. Our results demonstrate that BIMP exposure reduced cell viability. Moreover, it induced changes in mitochondrial membrane potential and increased cleavage of caspase 3. Treatment with BIMP increased the mRNA levels of the ER stress marker genes binding immunoglobulin protein (BiP) and the transcription factor C/EBP homologous protein (CHOP). Furthermore, BIMP increased the protein expressions and phosphorylation of BiP, CHOP, and protein kinase RNA-like ER kinase and the phosphorylation of eukaryotic translation initiation factor 2. Compared to BIMP treatment alone, pretreatment with the CHOP siRNA, siCHOP, decreased BIMP-dependent CHOP expression and improved CCF-STTG1 cell viability. Our findings suggest that BIMP induced mitochondrial dysfunction and apoptotic cell death event mediated by ER stress in CCF-STTG1 cells and that treatment targeted at managing ER stress has the potential to attenuate the toxicity of OP nerve agents.