An enzyme-free immunosorbent assay of staphylococcal enterotoxin B using a three-way DNA junction amplifier with an automatic reset function.

A highly sensitive immunoadsorption assay without traditional horseradish peroxidase for signal amplification was developed, utilizing a three-way DNA junction amplifier instead. The formation of a three-way DNA junction and release of trigger DNA with recycling was accomplished by toehold-mediated strand displacement. The fluorescent dye -methyl mesoporphyrin IX, with highly structure-specific binding affinity towards G-quadruplexes, was employed for label-free and simple signal output.

Identification and pharmacological properties of 2-(1H-indazole-3-carboxamido)-3,3-dimethylbutanoate (MDMB-INACA), N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)-1H-indazole-3-carboxamide (ADB-INACA), and N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)-1-hexyl-1H-indazole-3-carboxamide (ADB-HINACA).

Synthetic cannabinoids (SCs) are an evolving class of new psychoactive substances (NPS) with structurally various compounds that are increasing over the past few years. Therefore, they are initially hard to identify because of the lack of analytical information. Moreover, there is little to no information regarding the pharmacology of these compounds despite human abuse.

Forensic STR and SNP Genotyping of Formalin-Fixed Skeleton Samples With Illumina's ForenSeq System.

Formalin fixatives are widely used in forensics to preserve tissues. However, extracting high-quality genomic DNA from formalin-fixed samples is challenging. Traditional short tandem repeat (STR) analysis using capillary electrophoresis (CE) for forensic DNA typing frequently results in failure.

Inkjet Printing Patterned Plasmonic SERS Platform with Surface-Optimized Paper for Label-Free Detection of Illegal Drugs in Urine.

Rapid quantitative testing of illegal drugs is urgently needed for precisely cracking down on drug crimes. Herein, an optimized paper-based surface-enhanced Raman spectroscopy (SERS) platform with patterned printing of plasmonic nanoparticles was constructed for the on-site quick testing of illegal drugs in urine. The filter paper was first coated with a layer of positive-charged chitosan, so as to reduce its roughness by filling the holes of the cellulose matrix and enhance the adhesion of negative-charged silver ink.

Degradation and preservation of nitrites in whole blood.

Understanding the factors that influence nitrite degradation in whole blood and developing methods for its stable preservation are crucial for ensuring accurate and reliable forensic identification in cases of nitrite poisoning. This study systematically monitored nitrite degradation and changes in hemoglobin proportions across different initial nitrite concentrations and blood samples. It was revealed that high nitrite concentrations rapidly reduced deoxyhemoglobin levels within the first 15 minutes and subsequently reacted with oxyhemoglobin at a slower rate.

Nickel-Catalyzed Enantioselective C(sp)-C(sp) Cross-Electrophile Coupling of -Sulfonyl Styrenyl Aziridines with Alkyl Bromides.

Herein, we report the first example of a highly enantioselective alkylative aziridine ring opening. Under the catalysis of a chiral nickel/pyridine-imidazoline complex, asymmetric C(sp)-C(sp) cross-electrophile coupling between racemic -sulfonyl styrenyl aziridines and readily available primary alkyl bromides furnishes a variety of highly enantioenriched phenethylamine derivatives with complete regiocontrol and good functional group tolerance. Preliminary mechanistic studies support a reaction pathway consisting of regioselective iodolysis of aziridines and subsequent enantioconvergent coupling of the generated β-amino benzyl iodides with alkyl bromides.

Rapid and sensitive detection of etomidate based on functionalized copper nanoclusters fluorescent probe.

Etomidate as a non-barbiturate sedative, has central inhibitory effect and addiction and has been listed as a controlled drug in some countries due to the abusing trend nowadays. Therefore, rapid and sensitive detection of etomidate is of great significance. In this work, a novel fluorescent sensing probe (CuNCs@MIPs) based on copper nanoclusters (CuNCs) and molecular imprinted polymers (MIPs) has been firstly reported.

8-oxoguanine DNA glycosylase-1 may serve as biomarker of mechanical asphyxia.

Aim: To identify mtDNA and OGG1 as potential biomarker candidates for mechanical asphyxia.

Method: The human tissues are divided into experimental group (hanging and strangulation) and control groups (hemorrhagic shock, brain injury group, and poisoning group). Detected the expression of OGG1 and integrity of mtDNA in cardiac tissue of each group.

Application of Magnetic Materials Combined with Echo Mass Spectrometry System in Analysis of Illegal Drugs in Sewage.

The aim of this study is to solve the problems of the complicated pretreatment and high analytical cost in the detection technology of trace drugs and their metabolites in municipal wastewater. A high-performance magnetic sorbent was fsynthesized for the enrichment of trace drugs and their metabolites in wastewater to develop a magnetic solid-phase extraction pretreatment combined with the acoustic ejection mass spectrometry (AEMS) analytical method. The magnetic nanospheres were successfully prepared by magnetic nanoparticles modified with divinylbenzene and vinylpyrrolidone.

Building Uniformly Structured Polymer Memristors via a 2D Conjugation Strategy for Neuromorphic Computing.

Polymer memristors represent a highly promising avenue for the advancement of next-generation computing systems. However, the intrinsic structural heterogeneity characteristic of most polymers often results in organic polymer memristors displaying erratic resistive switching phenomena, which in turn lead to diminished production yields and compromised reliability. In this study, a 2D conjugated polymer, named PBDTT-BPQTPA, is synthesized by integrating the coplanar bis(thiophene)-4,8-dihydrobenzo[1,2-b:4,5-b]dithiophene (BDTT) as an electron-donating unit with a quinoxaline derivative serving as an electron-accepting unit.

Similarity quantification of bare footprint based on linear measurement and shape context contour combined score-based likelihood ratio evaluation.

Bare footprints are a type of physical evidence that can be crucial for solving difficult cases. To assist with identification, we explored a similarity quantification method using 3062 bare footprints from 1391 volunteers. We used linear similarity to cover seven linear lengths and then calculated the contour similarity of the heel region, anterior margin, and toe region using the shape context.

Syntheses of Cannabinoid Metabolites: Ajulemic Acid and HU-210.

Cannabinoid metabolites have been reported to be more potent than their parent compounds. Among them, ajulemic acid (AJA) is a side-chain analog of Δ-THC-11-oic acid, which would be a good template structure for the discovery of more potent analogues. Herein, we optimized the key allylic oxidation step to introduce the C-11 hydroxy group with a high yield.

Forensic Validation and Application Evaluation of IDentifier DNA Typing Kit (Yan-Huang34).

Objectives: To investigate the technical performance of IDentifier DNA typing kit (YanHuang34) and evaluate its forensic application value.

Methods: Following the (GB/T 37226-2018), IDentifier DNA typing kit (YanHuang34) was verified in 11 aspects of species specificity, veracity, sensibility, adaptability, inhibitor tolerance, consistency, balance, reaction condition verification, mixed samples, stability and inter batch consistency. The system efficiency of IDentifier DNA typing kit (YanHuang34) was compared with the PowerPlex Fusion 6C System, VersaPlex 27PY System and VeriFiler Plus PCR Amplification Kit.

The down-regulation of STC2 mRNA may serve as a biomarker for death from mechanical asphyxia.

Death from mechanical asphyxia (DMA) is a common cause of death in forensic pathology. However, due to the lack of biomarkers, the authentication of DMA now relies on a series of non-specific signs, which may cause troubles in the judicial trials, especially when the criminal scene is not fully elucidated. To search for the potential biomarkers for DMA, brain samples of DMA and craniocerebral injury groups were screened by microarray.

The Synthesis of Biphasic Metabolites of Carfentanil.

Carfentanil is an ultra-potent synthetic opioid. The Russian police force used both carfentanil and remifentanil to resolve a hostage incident in Moscow. This reported use sparked an interest in the pharmacology and toxicology of carfentanil in the human body, and data on its metabolites were later published.

A diagnostic strategy for pulmonary fat embolism based on routine H&E staining using computational pathology.

Pulmonary fat embolism (PFE) as a cause of death often occurs in trauma cases such as fractures and soft tissue contusions. Traditional PFE diagnosis relies on subjective methods and special stains like oil red O. This study utilizes computational pathology, combining digital pathology and deep learning algorithms, to precisely quantify fat emboli in whole slide images using conventional hematoxylin-eosin (H&E) staining.

The involvement of calcium in the toxic effect of 4-methylethcathinone on SH-SY5Y cells.

Neurotoxicity induced by psychoactive substances is often accompanied by an imbalance of intracellular calcium ions. It is unclear whether calcium ions play a role in the toxicity induced by psychoactive substances. In the present study, we aimed to evaluate the occurrence of calcium dysregulation and its contribution to cytotoxicity in human neurotypic SH-SY5Y cells challenged with a recently developed psychoactive substance 4-methylethcathinone (4-MEC).

Recognition of methamphetamine and other amines by trace amine receptor TAAR1.

Trace amine-associated receptor 1 (TAAR1), the founding member of a nine-member family of trace amine receptors, is responsible for recognizing a range of biogenic amines in the brain, including the endogenous β-phenylethylamine (β-PEA) as well as methamphetamine, an abused substance that has posed a severe threat to human health and society. Given its unique physiological role in the brain, TAAR1 is also an emerging target for a range of neurological disorders including schizophrenia, depression and drug addiction. Here we report structures of human TAAR1-G-protein complexes bound to methamphetamine and β-PEA as well as complexes bound to RO5256390, a TAAR1-selective agonist, and SEP-363856, a clinical-stage dual agonist for TAAR1 and serotonin receptor 5-HTR (refs.

Research Progress on Microbial Community Succession in the Postmortem Interval Estimation.

The postmortem interval (PMI) estimation is a key and difficult point in the practice of forensic medicine, and forensic scientists at home and abroad have been searching for objective, quantifiable and accurate methods of PMI estimation. With the development and combination of high-throughput sequencing technology and artificial intelligence technology, the establishment of PMI model based on the succession of the microbial community on corpses has become a research focus in the field of forensic medicine. This paper reviews the technical methods, research applications and influencing factors of microbial community in PMI estimation explored by using high-throughput sequencing technology, to provide a reference for the related research on the use of microbial community to estimate PMI.

Retrospective Analysis of Death Cases of Oral Diphenidol Hydrochloride Poisoning.

Objectives: To explore the characteristics of postmortem examination, chemical examination and scene investigation of deaths caused by oral diphenidol hydrochloride poisoning, and so as to provide a reference for proper settlement and prevention of such deaths.

Methods: The data of 22 deaths caused by oral diphenidol hydrochloride poisoning in a city from January 2018 to August 2020 were collected, including case details, scene investigations, autopsies, chemical examinations and digital evidence. Thirty-one cases of deaths caused by oral diphenidol hydrochloride poisoning reported in previous literature were also collected.

D-D dentition superimposition for individual identification: A study of an Eastern Chinese population.

Recently, 3D dental intraoral scanning technology has been developed rapidly and applied widely in everyday dental practice. Since 3D dental scanning could provide valuable personal information, it enabled researchers to develop novel procedures for individual identification through D-D dentition superimposition. This study aimed to test the applicability of this method in an Eastern Chinese population and propose a threshold for personal identification.

The correlation between CpG island methylation of hTERT promoter and human age prediction.

DNA methylation is an epigenetic modification that occurs during the life cycle of individuals. Its degree is closely associated with the methylation status of CpG sites in its promoter region. Based on the previous screening that the hTERT methylation is both related to tumors and age, we suspected that the age inference based on hTERT methylation would be disturbed by the disease of the tested person.

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.