Wulffmark1487

To explore the relationship between the frequency characteristics and response threshold of auditory steady-state response (ASSR), auditory brainstem response (ABR) and 40 Hz auditory event related potential (40 Hz AERP), and their application values in forensic medicine.

Thirty volunteers with normal hearing (60 ears) were selected to perform pure tone audiometry (PTA) threshold and ASSR, ABR and 40 Hz AERP response threshold tests in the standard sound insulation shielding room, and the results were statistically analyzed by SPSS 22.0 software.

At 0.5 kHz and 1.0 kHz frequencies, the correlation between 40 Hz AERP response threshold and PTA threshold was good, which was better than that of ASSR and ABR response threshold. At 2.0 kHz and 4.0 kHz frequencies, the correlation between ASSR and ABR response thresholds and PTA threshold was good, which was better than that of 40 Hz AERP response threshold.

To evaluate the hearing at 0.5 kHz and 1.0 kHz frequencies, it is recommended to use 40 Hz AERP and ASSR to comprehensively assess the PTA threshold of the subjects. To evaluate the hearing at 2.0 kHz and 4.0 kHz frequencies, ABR and ASSR are recommended to assess the PTA threshold of subjects comprehensively. The combination of ASSR, ABR and 40 Hz AERP can improve the accuracy of hearing function evaluation.

To evaluate the hearing at 0.5 kHz and 1.0 kHz frequencies, it is recommended to use 40 Hz AERP and ASSR to comprehensively assess the PTA threshold of the subjects. To evaluate the hearing at 2.0 kHz and 4.0 kHz frequencies, ABR and ASSR are recommended to assess the PTA threshold of subjects comprehensively. The combination of ASSR, ABR and 40 Hz AERP can improve the accuracy of hearing function evaluation.

To study the transcriptomic changes of astrocytes in the brain of rats exposed to methamphetamine (METH) and its possible mechanism in neurotoxicity.

The rats were intraperitoneally injected with METH (15 mg/kg) every 12 h for 8 times in total to establish the subacute rat model of METH. After the model was successfully established, the striatum was extracted, and astrocytes were separated by the magnetic bead method. Transcriptome sequencing was performed on selected astrocytes, and the differentially expressed genes were analyzed by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis.

A total of 876 differentially expressed genes were obtained by transcriptome sequencing, including 321 up-regulated genes and 555 down-regulated genes. GO analysis revealed that differentially expressed genes were mainly concentrated in cell structure, biological process regulation, extracellular matrix and organelle functions. KEGG pathway enrichment analysis showed that steroids biosynthesis, fatty acid biosynthesis, peroxisome proliferators-activated receptor (PPAR), adenosine 5'-monophosphate-activated protein kinase (AMPK) and other signaling pathways were significantly changed.

METH can cause structural changes of astrocytes through multiple targets, among which cellular structure, steroids biosynthesis and fatty acid biosynthesis may play an important role in nerve injury, providing a new idea for forensic identification of METH related death.

METH can cause structural changes of astrocytes through multiple targets, among which cellular structure, steroids biosynthesis and fatty acid biosynthesis may play an important role in nerve injury, providing a new idea for forensic identification of METH related death.

To investigate the inhibitory effect of cholecystokinin octapeptide (CCK-8) binding to cholecystokinin 2 receptor (CCK2R) on methamphetamine (METH)-induced neuronal apoptosis, and to explore the signal transduction mechanism of β-arrestin 2 in CCK-8 inhibiting METH-induced neuronal apoptosis.

SH-SY5Y cell line was cultured, and HEK293-CCK1R and HEK293-CCK2R cell line were constructed by lentivirus transfection. Small interfering RNA (siRNA) was used to knockdown the expression of β-arrestin 2. Annexin Ⅴ-FITC/PI staining and flow cytometry were used to detect the apoptotic rate of cells, and Western blotting was used to detect the expression of apoptosis-related proteins.

The apoptosis of SH-SY5Y cells was induced by 1 mmol/L and 2 mmol/L METH treatment, the number of nuclear fragmentation and pyknotic cells was significantly increased, and the expression of apoptosis-related proteins Bax and cleaved caspase-3 were increased. CCK-8 pre-treatment at the dose of 0.1 mmol/L and 1 mmol/L significantly reversed METH-induced apoptosis in SH-SY5Y cells, and inhibited cell nuclear fragmentation, pyknosis and the changes of apoptosis-related proteins induced by METH. In lentivirus transfected HEK293-CCK1R and HEK293-CCK2R cells, the results revealed that CCK-8 had no significant effect on METH-induced changes of apoptosis-related proteins in HEK293-CCK1R cells, but it could inhibit the expression level of apoptosis-related proteins in HEK293-CCK2R cells induced by METH. The inhibitory effect of CCK-8 on METH-induced apoptosis was blocked by the knockdown of β-arrestin 2 expression in SH-SY5Y cells.

CCK-8 can bind to CCK2R and exert an inhibitory effect on METH-induced apoptosis by activating the β-arrestin 2 signal.

CCK-8 can bind to CCK2R and exert an inhibitory effect on METH-induced apoptosis by activating the β-arrestin 2 signal.Abuse of pharmaceutical drugs is a major public health and social problem worldwide. Mostly abused drugs mainly include opioids such as morphine, tramadol, methadone and fentanyl, sedative-hypnotics such as benzodiazepines and non-benzodiazepines, and central stimulants such as Ritalin (methylphenidate), Adderall (amphetamine and dextroamphetamine) and modafinil. Abuse of pharmaceutical drugs not only causes direct damage to multiple systems of the body, but also significantly increases risks of mental and physical diseases, imposing a heavy burden on individuals, families and society. Therefore, the prevention and control of pharmaceutical drug abuse are of vital importance. The Chinese government has taken strict administration measures for pharmaceutical drugs with abuse risk. However, confronting endless new drugs and changing abuse trends, it is necessary to further strengthen management and prevention of pharmaceutical drugs, monitor the trend of abuse, establish rapid response mechanisms, popularize relevant knowledge, and develop specific therapeutic drugs and intervention means, in order to promote prevention and treatment of pharmaceutical drug abuse.The mechanism of methamphetamine toxicity and addiction is the key research direction of forensic toxicology, and the development of omics technology provides a new platform for further study of this direction. METH toxic damage and addiction are reflected differently in genes, ribonucleic acid (RNA) transcription, protein and metabolism. This article summarizes the achievements and shortcomings of multi-omics technologies such as genome, transcriptome, metabolome and proteome in the study of METH damage and addiction, and discusses the strategies and advantages of multi-omics combined analysis in the study of METH toxic damage and addiction mechanism, in order to provide more useful reference information for forensic toxicology of METH.Drug problem is a major social and public security problem in the world. Drug abuse poses a great threat to economic development, social stability and public health. In recent years, synthetic drugs represented by methamphetamine have surpassed traditional drugs such as morphine, heroin, ketamine and become one of the most abused drugs in the world. In order to solve the problem of drug abuse, it is of great theoretical value and practical significance to carry out all-round and multi-level scientific research on drug-related issues. KRpep-2d order Based on the current situation of drug abuse, this article reviews research progresses on the epidemiology of methamphetamine abuse, the monitoring technology, the basic researches on toxicity damage, the withdrawal drug screening, the related clinical comorbidity and the testing technologies, comprehensively presenting the development trend of methamphetamine abuse related issues.The drug budesonide exists as 22R and 22S enantiomers. However, the drug activity of 22R-budesonide is 2-3 times stronger than that of 22S-budesonide. The development of enantiomeric separation and quantitative analysis methods for budesonide can provide an important basis for its drug development and quality control. At present, the enantiomers of budesonide are separated on a reversed C18 solid phase column. However, chiral stationary phases are rarely reported for the separation of the enantiomers of budesonide. In this study, a high performance liquid chromatography (HPLC) method with a chiral stationary phase was developed for the rapid separation and determination of budesonide enantiomers. The effects of the type of chiral stationary phase, mobile phase additives, and column temperature on the resolution of the budesonide enantiomers were also investigated. The results showed that the chiral stationary phase amylose-tris-[(S)-1-phenylethyl carbamate] was more suitable for the separation of budesonide e 283.15-284.63 μg/mL and 259.86-261.51 μg/mL, respectively. This method is simple and rapid, in addition to having good repeatability and high accuracy. It can be used for the resolution of budesonide enantiomers and for quality control in budesonide preparations.Sulfur-doped graphene quantum dots (S-GQDs) were prepared by the pyrolysis of citric acid and mercaptopropionic acid. Compared with graphene quantum dots (GQDs), the S-GQDs have improved surface state and chemical reactivity, and thus, exhibited stronger interaction with cations. Based on its excellent affinity for cations, a dual preconcentration technique combining field-amplified sample injection (FASI) and S-GQDs as multianalyte carriers was developed for the determination of melamine and dicyandiamide by capillary electrophoresis (CE). During the FASI process, a large quantity of analytes was introduced into the capillary and accumulated at the capillary inlet. Concurrently, the S-GQDs migrated to the anode and captured the analytes on its surface at the boundary of the sample and buffer solution. The use of S-GQDs allows the capture of abundant analytes, which can amplify the detection signal. This new protocol was evaluated by the quantitative determination of melamine and dicyandiamide in metformin hyiations (RSDs) of no more than 5%. The RSD values of peak height, peak area, and migration time were all less than 5.6%. This method is reliable, easy, and exhibits a good separation effect. This proves that the S-GQD-enhanced CE method could be developed into a new and sensitive technique for the determination of melamine and dicyandiamide in different preparations of metformin hydrochloride.Understanding the diffusion behavior of particles during chromatographic analysis is critical for optimizing the operation conditions, improving the chromatographic performance, and designing a new separation device. Most of the existing simulations focus on chromatographic thermodynamics, while very few consider the overall diffusion and separation process. Herein, a new simulation method for gas chromatography separation was developed based on the random diffusion theory in microscale restricted space. This method retained the key information for controlling the diffusion behavior, simplified the interaction between the particles to be separated, and enlarged the time scale of each step one molecule walks. Thus, the operational efficiency could be significantly improved due to reduced calculation, and the entire diffusion process in the gas chromatography capillary column could be simulated. In this model, the capillary column was represented by a two-dimensional long and narrow rectangle where the particles to be separated randomly diffused.