Dual-Mode Separation and SERS Detection of Carbaryl with PA-6/AuNRs@ZIF-8 Films.

Appropriate separation and enrichment steps can enhance the performance of SERS assays. For rapid, in-situ detection of carbaryl, a novel PA-6/AuNRs@ZIF-8 film that can be applied to dual-mode separation and SERS detection, has been developed. In the film, PA-6 was used as a TLC substrate for the initial separation of the substance to be measured. ZIF-8 provides chemical enhancement in SERS as well as enrichment and secondary separation of the analytes. Utilizing this film, we have successfully implemented a TLC-SERS rapid detection scheme, resulting in a detection limit for carbaryl as low as 1 × 10-9 M in lake water in 15 min, which is significantly lower than existing standards. Additionally, the manufacturing cost of one PA-6/AuNRs@ZIF-8 film can be kept within the range of $0.20-$0.40 economically, presenting substantial financial advantages. The method is highly promising for pesticide detection as well as forensic in-situ testing.

Predicting the structure of unexplored novel fentanyl analogues by deep learning model.

Fentanyl and its analogues are psychoactive substances and the concern of fentanyl abuse has been existed in decades. Because the structure of fentanyl is easy to be modified, criminals may synthesize new fentanyl analogues to avoid supervision. The drug supervision is based on the structure matching to the database and too few kinds of fentanyl analogues are included in the database, so it is necessary to find out more potential fentanyl analogues and expand the sample space of fentanyl analogues. In this study, we introduced two deep generative models (SeqGAN and MolGPT) to generate potential fentanyl analogues, and a total of 11 041 valid molecules were obtained. The results showed that not only can we generate molecules with similar property distribution of original data, but the generated molecules also contain potential fentanyl analogues that are not pretty similar to any of original data. Ten molecules based on the rules of fentanyl analogues were selected for NMR, MS and IR validation. The results indicated that these molecules are all unreported fentanyl analogues. Furthermore, this study is the first to apply the deep learning to the generation of fentanyl analogues, greatly expands the exploring space of fentanyl analogues and provides help for the supervision of fentanyl.

YAP/TAZ activation mediates PQ-induced lung fibrosis by sustaining senescent pulmonary epithelial cells.

Paraquat (PQ) is a widely used herbicide and a common cause of poisoning that leads to pulmonary fibrosis with a high mortality rate. However, the underlying mechanisms of PQ-induced pulmonary fibrosis and whether pulmonary epithelial cell senescence is involved in the process remain elusive. In this study, PQ-induced pulmonary epithelial cell senescence and Hippo-YAP/TAZ activation were observed in both C57BL/6 mice and human epithelial cells. PQ-induced senescent pulmonary epithelial cells promoted lung fibroblast transformation through secreting senescence-associated secretory phenotype (SASP) factors. Yap/Taz knockdown in mice lungs significantly decreased the expression of downstream profibrotic protein Ctgf and senescent markers p16 and p21, and alleviated PQ-induced pulmonary fibrosis. Interfering YAP/TAZ in senescent human pulmonary epithelial cells resulted in decreased expression of the anti-apoptosis protein survivin and elevated level of apoptosis. In conclusion, our findings reveal a novel mechanism by which the involvement of Hippo-YAP/TAZ activation in pulmonary epithelial cell senescence mediates the pathogenesis of PQ-induced pulmonary fibrosis, thereby offering novel insights and potential targets for the clinical management of PQ poisoning as well as providing the mechanistic insight of the involvement of Yap/Taz activation in cell senescence in pulmonary fibrosis and its related pulmonary disorders. The YIN YANG balance between cell senescence and apoptosis is important to maintain the homeostasis of the lung, the disruption of which will lead to disease.

Non-cytochrome P450 enzyme aldehyde oxidase is involved in the oxidative metabolic pathway of diquat and its detoxification effect.

Diquat (DQ) poisoning has garnered attention in recent years, primarily due to the rising incidence of cases worldwide, coupled with the absence of a viable antidote for its treatment. Despite the fact that diquat monopyridone (DQ-M) has been identified as a significant metabolite of DQ, the enzyme responsible for its formation remains unknown. In this study, we have identified aldehyde oxidase (AOX) as a vital enzyme involved in DQ oxidative metabolism. The metabolism of DQ to DQ-M was significantly inhibited by AOX inhibitors including raloxifene and hydralazine. The source of oxygen incorporated into DQ-M was proved to be from water through a H218O incubation experiment which further corroborated DQ-M formation via AOX metabolism. The product of DQ-M in vitro generated by fresh rat tissues co-incubation was consistent with its AOX expression. The result of the molecular docking analysis of DQ and AOX protein showed that DQ is capable of binding to AOX. Furthermore, the cytotoxicity of DQ was significantly higher than DQ-M at the same concentration tested in six cell types. This work is the first to uncover the involvement of aldehyde oxidase, a non-cytochrome P450 enzyme, in the oxidative metabolic pathway of diquat, thus providing a potential target for the development of detoxification treatment.

Genome-wide association studies combined with k-fold cross-validation identify rs17822931 as an ancestry-informative marker in Han Chinese population.

DNA-based ancestry inference has long been a research hot spot in forensic science. The differentiation of Han Chinese population, such as the northern-to-southern substructure, would benefit forensic practice. In the present study, we enrolled participants from northern and southern China, each participant was genotyped at ∼400 K single-nucleotide polymorphisms (SNPs) and data of CHB and CHS from 1000 Genomes Project were used to perform genome-wide association analyses. Meanwhile, a new method combining genome-wide association study (GWAS) analyses with k-fold cross-validation in a small sample size was introduced. As a result, one SNP rs17822931 emerged with a p-value of 7.51E - 6. We also simulated a huge dataset to verify whether k-fold cross-validation could reduce the false-negative rate of GWAS. The identified ABCC11 rs17822931 has been reported to have allele frequencies varied with the geographical gradient distribution in humans. We also found a great difference in the allele frequency distributions of rs17822931 among five different cohorts of the Chinese population. In conclusion, our study demonstrated that even small-scale GWAS can also have potential to identify effective loci with implemented k-fold cross-validation method and shed light on the potential maker of rs17822931 in differentiating the north-to-south substructure of the Han Chinese population.

Development of a simple and reliable method for α-amanitin detection in rat plasma and its application to a toxicokinetic study.

RATIONALE: α-Amanitin is a highly toxic peptide widely found in species of poisonous mushrooms. The matrix effect has been a major obstacle for accurate determination of α-amanitin in plasma samples by liquid chromatography/tandem mass spectrometry (LC/MS/MS). In this study, the strategy to eliminate the matrix effect of α-amanitin with a one-step dilution approach after deproteinization was applied. METHODS: Rat plasma samples were processed by protein precipitation with methanol followed by a nine-fold dilution with pure water. The matrix effect value of α-amanitin was 19.7%-22.2% by protein precipitation and then changed to 87.5%-88.7% after dilution. α-Amanitin and the internal standard (roxithromycin) were analyzed on an ACQUITY UPLC® BEH C18 (50 mm × 2.1 mm, 1.7 µm) column within 3.0 min by gradient elution. RESULTS: The linear ranges were 0.90-600 ng/mL with a correlation coefficient r >0.9958. A lower limit of quantification (LLOQ) of 0.90 ng/mL was achieved using only 50 µL of rat plasma. The intra- and inter-day precisions for the analyte ranged from 3.2% to 7.5% and 3.1% to 7.1%, respectively, and the accuracy ranged from -5.3% to -8.0%. CONCLUSIONS: The matrix effect of α-amanitin was reduced by sample dilution after plasma deproteinization. A reliable LC/MS/MS method for the determination of α-amanitin in rat plasma was developed. This method was successfully applied for a toxicokinetic study of rats after intravenous injection of α-amanitin with a subacute toxicity dose at 0.10 mg/kg.

Unconventional Passive Enhancement of Transdermal Drug Delivery: toward a Mechanistic Understanding of Penetration Enhancers Releasing from Acrylic Pressure-Sensitive Adhesive of Patches.

PURPOSE: Penetration enhancers (PEs) enhancing efficacy depends on two processes: PEs release from patches and action on skin. Compared with their action on skin, PEs release process was poorly understood. Therefore, the purpose of this study was to make a mechanistic understanding of PEs release from acrylic pressure-sensitive adhesive of patches and propose an unconventional enhancement of PEs efficacy. METHODS: PEs efficacy was evaluated both in drug permeation study and drug pharmacokinetic study. Confocal Raman spectroscopy was employed to observe PEs release behavior by mapping PEs dynamic distribution in skin. The mechanism of PEs release behavior was provided from molecular interaction and rheology using FT-IR, molecular docking, molecular dynamic simulation and rheometer, separately. RESULTS: The release behavior of PEs themselves greatly restricted their efficacy. By using PEG 400, an improvement of oleic acid (OA) release behavior was achieved, and the efficacy of OA was significantly enhanced with enhancing ratio (ER) from 2.69 to 4.10 and AUClast from 1574 ± 87 to 2664 ± 249 ng·h/mL, separately. The improvement of OA release behavior was primarily resulted from reduction of the interaction between OA and adhesive, which was caused by other small molecules with a strong ability in forming hydrogen bonds with adhesive. Also, the rigidity of adhesive was a factor in affecting PEs release behavior. CONCLUSIONS: An unconventional passive enhancement of transdermal drug delivery was achieved via improving PEs themselves releasing from acrylic pressure-sensitive adhesive. Graphical abstract Influence of PEs release behavior on drug permeation through skin and molecular mechanism.

Investigation of heart lipid changes in acute ß-AR activation-induced sudden cardiac death by time-of-flight secondary ion mass spectrometry.

Sudden cardiac death (SCD), one of the most common causes of human death, has become a major health and social problem. The postmortem diagnosis and prevention of SCD remain primary challenges in the medical community due to the lack of reliable diagnostic biomarkers. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is a sensitive surface analysis technique for analyzing tissue slices with high spatial resolution. Here, ToF-SIMS followed by principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were employed to study the SCD mouse myocardium samples and obtain high-resolution chemical mappings and mass spectra. Distinction between normal control (NC) and acute ß-adrenergic receptor (ß-AR) activation-induced SCD groups was primarily due to the changes of diacylglycerols (DAG), phosphatidylcholine (PC), lysophosphatidylcholine (LysoPC) and sphingomyelin (SM) in positive mode. Meanwhile, chemical mapping of the myocardium showed different lipid distributions in the SCD mouse myocardium. The metabolite alterations in mouse models were further verified by analyzing the heart tissue sections of a 28-year-old woman that died from isoprenaline injection. This pilot study demonstrated the significance of ToF-SIMS in characterizing the lipid variations in SCD heart tissues and might contribute to the postmortem diagnosis of SCD, the discovery of molecule candidates to discriminate the progression of SCD and the understanding of the potential postmortem diagnostic significance of SCD.

Correction: Investigation of heart lipid changes in acute ß-AR activation-induced sudden cardiac death by time-of-flight secondary ion mass spectrometry.

Correction for 'Investigation of heart lipid changes in acute ß-AR activation-induced sudden cardiac death by time-of-flight secondary ion mass spectrometry' by Jia-Qian Lou, et al., Analyst, 2020, DOI: 10.1039/d0an00768d.

Swietenine extracted from Swietenia relieves myocardial hypertrophy induced by isoprenaline in mice.

As a traditional plant medicine in tropical areas, Swietenia macrophylla seeds are usually applied for some chronic diseases, including hypertension, diabetes, and so on. Few studies have been carried out to identify the effective elements in seed extract and their indications. In this study, we first investigated the functions of the swietenine, an extract from S. macrophylla seeds, using a model of myocardial hypertrophy induced by isoprenaline (ISO). At cellular level, H9c2 cell hypertrophy was also established through the treatment with ISO. The cardiac pathological remodeling was evaluated by echocardiography and histological analysis. Western blot and RT-qPCR were used to detect the expression of possible hypertrophy-promoting genes. Here, our results indicated that swietenine remarkably attenuated ISO-induced myocardial hypertrophy in vivo and in vitro. Moreover, Akt phosphorylation, ANP and BNP mRNA expression were efficiently decreased. Based on these findings, we concluded that swietenine might be a promising anti-hypertrophic agent against cardiac hypertrophy.

Aldehyde oxidase-dependent species difference in hepatic metabolism of fasudil to hydroxyfasudil.

1. An investigation on the metabolic mechanism of fasudil to hydroxyfasudil was conducted in vitro using liver subcellular fractions of different species. Hydroxyfasudil was generated in large amounts by rat liver S9 and to a similar extent by human liver S9 but was not detected in dog liver S9 incubations. 2. Studies with various molybdenum hydroxylase inhibitors demonstrated that aldehyde oxidase (AO), but not xanthine oxidase (XO), selectively catalyzed fasudil to hydroxyfasudil in both rat and human liver cytosol. In addition, the oxygen atom incorporated into hydroxyfasudil was derived from water rather than atmospheric oxygen, which further corroborated AO involvement. 3. Enzyme kinetics experiments revealed that fasudil had a higher affinity to human hepatic AO than to rat hepatic AO. Besides, significantly different in vivo pharmacokinetic parameters observed between male and female rats indicated that the AO activity in rats was gender-dependent. 4. The present study provided first evidences that AO causes differences in fasudil metabolism between species.

A simplified LC-MS/MS method for rapid determination of cycloserine in small-volume human plasma using protein precipitation coupled with dilution techniques to overcome matrix effects and its application to a pharmacokinetic study.

Matrix effects have been a major concern when developing LC-MS/MS methods for quantitative bioanalysis of cycloserine. Sample handling procedures including solid phase extraction or derivatization have been reported previously by researchers to overcome matrix effects of cycloserine. In the present study, the possibility of reducing matrix effects of cycloserine using protein precipitation coupled with dilution techniques was investigated. Plasma samples were pretreated by protein precipitation with methanol followed by a 40-fold dilution with methanol-water (50:50, v/v). The analyte and the internal standard (mildronate) were chromatographed on a Shim-pack XR-ODS (100 mm × 2.0 mm, 2.2 µm) column using methanol-0.01% formic acid (70:30, v/v) as mobile phase and detected by multiple reaction monitoring mode via positive electrospray ionization. The total run time was only 2 min per sample. The suppression of cycloserine response was reduced with the matrix effects ranging between 80.5 and 87.9%. A lower limit of quantification (LLOQ) of 0.300 µg/mL was achieved using only 10 µL of plasma. The intra- and inter-day precisions were less than 4.8% and the accuracy ranged from -2.6 to 6.6%. The method was successfully applied to a pharmacokinetic study of cycloserine in 30 healthy Chinese male subjects after oral administration of a single dose of cycloserine at 250, 500 and 750 mg under fasting conditions. The newly developed method is simpler, faster, cost-effective, and more robust than previously reported LC-MS/MS methods.

Rapid and cost-effective method for the simultaneous quantification of seven alkaloids in Corydalis decumbens by microwave-assisted extraction and capillary electrophoresis.

A rapid and cost-effective method based on microwave-assisted extraction followed by capillary electrophoresis was developed for simultaneous quantification of seven alkaloids in Corydalis decumbens for the first time. The main parameters affecting microwave-assisted extraction and capillary electrophoresis separation were investigated and optimized. The optimal microwave-assisted extraction was performed at 40°C for 5 min using methanol/water (90:10, v/v) as the extracting solvent. Electrophoretic separation was achieved within 15 min using an uncoated fused-silica capillary (50 µm internal diameter and 27.7 cm effective length) and a 500 mM Tris buffer containing 45% v/v methanol (titrated to pH* 2.86 with H3 PO4 ). The developed method was successfully applied to the quantification of seven alkaloids in Corydalis decumbens obtained from different regions of China. The combination of microwave-assisted extraction with capillary electrophoresis was an effective method for the rapid analysis of the alkaloids in Corydalis decumbens.

The value of toxicological analysis in acute poisoning patients with uncertain exposure histories: a retrospective and descriptive study from an institute of poisoning.

BACKGROUND: In clinical practice, some patients might not be able or unwilling to provide a thorough history of medication and poison exposure. The aim of this study was to use toxicological analysis to examine the clinical characteristics of patients with acute poisoning whose exposure history was uncertain from a toxicological analysis perspective. METHODS: This was a retrospective and descriptive study from an institute of poisoning. Patient registration information and test reports spanning the period from April 1, 2020 to March 31, 2022, were obtained. Patients with uncertain exposure histories and who underwent toxicological analysis were included. Clinical manifestations and categories of toxics were analyzed. RESULTS: Among the 195 patients with positive toxicological analysis results, the main causes of uncertain exposure history was disturbance of consciousness (62.6%), unawareness (23.6%) and unwillingness or lack of cooperation (13.8%). The predominant clinical manifestations were disturbed consciousness (62.6%), followed by vomiting and nausea (14.4%) and liver function abnormalities (8.7%). A comparison of clinical manifestations between patients with positive and negative (n=99) toxicological analyses results revealed significantly different proportions of disturbances in consciousness (63% vs. 21%), dizziness (1.5% vs. 5.1%), multi-organ failure (1.5% vs. 7.1%), and local pain (0 vs 4%). The main categories of substances involved were psychiatric medications (23.1%), sedatives (20.5%), insecticides (13.8%), and herbicides (12.8%). CONCLUSION: The clinical manifestations of acute poisoning in patients with an uncertain exposure history are diverse and nonspecific, and toxicological analysis plays a pivotal role in the diagnosis and differential diagnosis of such patients.

Multi-Omics Analyses Reveal the Mechanisms of Early Stage Kidney Toxicity by Diquat.

Diquat (DQ), a widely used bipyridyl herbicide, is associated with significantly higher rates of kidney injuries compared to other pesticides. However, the underlying molecular mechanisms are largely unknown. In this study, we identified the molecular changes in the early stage of DQ-induced kidney damage in a mouse model through transcriptomic, proteomic and metabolomic analyses. We identified 869 genes, 351 proteins and 96 metabolites that were differentially expressed in the DQ-treated mice relative to the control mice (p < 0.05), and showed significant enrichment in the PPAR signaling pathway and fatty acid metabolism. Hmgcs2, Cyp4a10, Cyp4a14 and Lpl were identified as the major proteins/genes associated with DQ-induced kidney damage. In addition, eicosapentaenoic acid, linoleic acid, palmitic acid and (R)-3-hydroxybutyric acid were the major metabolites related to DQ-induced kidney injury. Overall, the multi-omics analysis showed that DQ-induced kidney damage is associated with dysregulation of the PPAR signaling pathway, and an aberrant increase in Hmgcs2 expression and 3-hydroxybutyric acid levels. Our findings provide new insights into the molecular basis of DQ-induced early kidney damage.

Swietenine Alleviates Vascular Remodelling by Enhancing Mitophagy of Pulmonary Arterial Smooth Muscle Cells in Experimental Pulmonary Hypertension.

BACKGROUND: Vascular remodelling during pulmonary hypertension (PH) is characterized by the phenotypic transformation of pulmonary arterial smooth muscle cells (PASMCs). Swietenine (Swi), extracted from the seeds of traditional medicine Swietenia mahagoni, has been used to treat cardiac remodelling, but the effect of Swi on PH is unknown. This study aims to evaluate the effect of Swi on hypoxia-induced phenotypic transformation of PASMCs in experimental PH. METHODS: In our research, C57BL/6 mice were treated with SU5416 and exposed to hypoxia for 4 weeks to establish HySu-PH model. Mice in the Swi treatment group were subjected to HySu with daily administration of Swi. Hemodynamic parameters, echocardiography, and degree of vascular muscularization were measured to evaluate the PH model. Proliferation of PASMC was assessed by Ki67 and EdU assay. Cell migration was detected by wound-healing assay. Mitophagy levels were evaluated by mito-tracker and lyso-tracker, autophagic flux, and protein expression of Pink1 and Lc3 II. The molecular docking was used to validate the interaction of Swi with Nrf2. Immunofluorescence and immunohistochemical staining were applied to determine the subcellular localization of Nrf2. RESULTS: The results showed that Swi attenuated hypoxia-induced increase of right ventricle systolic pressure, Fulton index, and vascular remodelling and decreased PASMC proliferation, migration, and enhanced mitophagy. Furthermore, the interaction of Swi with Nrf2 promoted the translocation of Nrf2 into the nucleus, resulting in the induction of Pink1. CONCLUSIONS: This study demonstrates that Swi prevents vascular remodelling in experimental PH through inhibition of phenotypic transformation and hyperproliferation of PASMCs caused by reversing hypoxia-induced inhibition of mitophagy.

Evaluation of a SNP-STR haplotype panel for forensic genotype imputation.

Short tandem repeat polymorphism (STR)-based individual identification is a popular and reliable method in many forensic applications. However, STRs still frequently fail to find any matched records. In such cases, if known STRs could provide more information, it would be very helpful to solve specific problems. Genotype imputation has long been used in the study of single nucleotide polymorphisms (SNPs) and has recently been introduced into forensic fields. The idea is that, through a reference haplotype panel containing SNPs and STRs, we can obtain unknown genetic information through genotype imputation based on known STR or SNP genotypes. Several recent studies have already demonstrated this exciting idea, and a 1000 Genomes SNP-STR haplotype panel has also been released. To further study the performance of genotype imputation in forensic fields, we collected STR, microhaplotype (MH) and SNP array genotypes from Chinese Han population individuals and then performed genotype imputation analysis based on the released reference panel. As a result, the average locus imputation accuracy was ∼83 % (or ∼70 %) when SNPs in the SNP array (or MH SNPs) were imputed from STRs, and was ∼30 % when highly polymorphic markers (STRs and MHs) were imputed from each other. When STRs were imputed from SNP array, the average locus imputation accuracy increased to ∼48 %. After analyzing the match scores between real STRs and the STRs imputed from SNPs, ∼80 % of studied STR records can be connected to corresponding SNP records, which may help for individual identification. Our results indicate that genotype imputation has great potential for forensic applications.