Haplotype-phased genome unveils the butylphthalide biosynthesis and homoploid hybrid origin of Ligusticum chuanxiong.

Butylphthalide is one of the first-line drugs for ischemic stroke therapy, while no biosynthetic enzyme for butylphthalide has been reported. Here, we present a haplotype-resolved genome of Ligusticum chuanxiong, a long-cultivated and phthalide-rich medicinal plant in Apiaceae. On the basis of comprehensive screening, four Fe(II)- and 2-oxoglutarate-dependent dioxygenases and two CYPs were mined and further biochemically verified as phthalide C-4/C-5 desaturases (P4,5Ds) that effectively promoted the forming of (S)-3-n-butylphthalide and butylidenephthalide. The substrate promiscuity and functional redundancy featured for P4,5Ds may contribute to the high phthalide diversity in L. chuanxiong. Notably, comparative genomic evidence supported L. chuanxiong as a homoploid hybrid with Ligusticum sinense as a potential parent. The two haplotypes demonstrated exceptional structure variance and diverged around 3.42 million years ago. Our study is an icebreaker for the dissection of phthalide biosynthetic pathway and reveals the hybrid origin of L. chuanxiong, which will facilitate the metabolic engineering for (S)-3-n-butylphthalide production and breeding for L. chuanxiong.

Extraordinary preservation of gene collinearity over three hundred million years revealed in homosporous lycophytes.

Homosporous lycophytes (Lycopodiaceae) are a deeply diverged lineage in the plant tree of life, having split from heterosporous lycophytes (Selaginella and Isoetes) ~400 Mya. Compared to the heterosporous lineage, Lycopodiaceae has markedly larger genome sizes and remains the last major plant clade for which no chromosome-level assembly has been available. Here, we present chromosomal genome assemblies for two homosporous lycophyte species, the allotetraploid Huperzia asiatica and the diploid Diphasiastrum complanatum. Remarkably, despite that the two species diverged ~350 Mya, around 30% of the genes are still in syntenic blocks. Furthermore, both genomes had undergone independent whole genome duplications, and the resulting intragenomic syntenies have likewise been preserved relatively well. Such slow genome evolution over deep time is in stark contrast to heterosporous lycophytes and is correlated with a decelerated rate of nucleotide substitution. Together, the genomes of H. asiatica and D. complanatum not only fill a crucial gap in the plant genomic landscape but also highlight a potentially meaningful genomic contrast between homosporous and heterosporous species.

B-cell maturation antigen chimeric antigen receptor-T therapy alleviated heart failure in patients with multiple myeloma.

Patients with multiple myeloma (MM) are likely to achieve poor therapeutic response when organs are involved. We produced anti-B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR)-T cells, which are in a trial for patients with relapsed/refractory MM. One enrolled patient developed severe heart failure, highly suspected as light chain cardiac amyloidosis. He exhibited increased N-terminal pro-brain natriuretic peptide with a peak of 32 299 ng/mL and heart failure with an ejection fraction of 30%. Anti-BCMA CAR-T cells were administered following lymphodepletion. The patient achieved cardiac response within 1 week with a decrease in N-terminal pro-brain natriuretic peptide by 80%, an increase in ejection fraction from 30% to 56%, and a haematological response with negative minimal residual disease at 1 month and a complete response at 1 year. To date, this patient has maintained good health without heart failure or haematological relapse. Herein, we show the efficacy of anti-BCMA CAR-T cells in patients with MM and severe heart failure.

[Screening and expression analysis of transcription factors involved in genuineness of Codonopsis pilosula in Shanxi].

This study aims to mine the transcription factors that affect the genuineness of Codonopsis pilosula in Shanxi based on the transcriptome data of C. pilosula samples collected from Shanxi and Gansu, and then analyze the gene expression patterns, which will provide a theoretical basis for the molecular assisted breeding of C. pilosula. Gene ontology(GO) functional annotation, conserved motif prediction, and gene expression pattern analysis were performed for the differential transcription factors predicted based on the transcriptome data of C. pilosula from different habitats. A total of 61 differentially expressed genes(DEGs) were screened out from the transcriptome data. Most of the DEGs belonged to AP2/ERF-ERF family, with the conserved motif of [2X]-[LG]-[3X]-T-[3X]-[AARAYDRAA]-[3X]-[RG]-[2X]-A-[2X]-[NFP]. Forty-three of the DEGs showed significantly higher gene expression in C. pilosula samples from Shanxi than in the samples from Gansu, including 11 genes in the AP2/ERF-ERF family, 5 genes in the NAC fa-mily, 1 gene in the bHLH family, and 2 genes in the RWP-RK family, while 18 transcription factors showed higher expression levels in the samples from Gansu. GO annotation predicted that most of the DEGs were enriched in GO terms related to transcriptional binding activity(103), metabolic process(26), and stress response(23). The expression of transcription factor genes, CpNAC92, CpNAC100, CpbHLH128, and CpRAP2-7 was higher in the samples from Shanxi and in the roots of C. pilosula. CpNAC92, CpbHLH128, and CpRAP2-7 responded to the low temperature, temperature difference, and iron stresses, while CpNAC100 only responded to low temperature and iron stresses. The screening and expression analysis of the specific transcription factors CpNAC92, CpNAC100, CpbHLH128, and CpRAP2-7 in C. pilosula in Shanxi laid a theoretical foundation for further research on the mechanism of genuineness formation of C. pilosula.

Multiomics comparison among populations of three plant sources of Amomi Fructus.

Amomi Fructus (Sharen, AF) is a traditional Chinese medicine (TCM) from three source species (or varieties), including Wurfbainia villosa var. villosa (WVV), W. villosa var. xanthioides (WVX), or W. longiligularis (WL). Among them, WVV has been transplanted from its top-geoherb region, Guangdong, to its current main production area, Yunnan, for >50 years in China. However, the genetic and transcriptomic differentiation among multiple AF source species (or varieties) and between the origin and transplanted populations of WVV is unknown. In our study, the observed overall higher expression of terpenoid biosynthesis genes in WVV than in WVX provided possible evidence for the better pharmacological effect of WVV. We also screened six candidate borneol dehydrogenases (BDHs) that potentially catalyzed borneol into camphor in WVV and functionally verified them. Highly expressed genes at the P2 stage of WVV, Wv05G1424 and Wv05G1438, were capable of catalyzing the formation of camphor from (+)-borneol, (-)-borneol and DL-isoborneol. Moreover, the BDH genes may experience independent evolution after acquiring the ancestral copies, and the following tandem duplications might account for the abundant camphor content in WVV. Furthermore, four populations of WVV, WVX, and WL are genetically differentiated, and the gene flow from WVX to WVV in Yunnan contributed to the greater genetic diversity in the introduced population (WVV-JH) than in its top-geoherb region (WVV-YC), which showed the lowest genetic diversity and might undergo genetic degradation. In addition, terpene synthesis (TPS) and BDH genes were selected among populations of multiple AF source species (or varieties) and between the top- and non-top-geoherb regions, which might explain the difference in metabolites between these populations. Our findings provide important guidance for the conservation, genetic improvement, and industrial development of the three source species (or varieties) and for identifying top-geoherbalism with molecular markers, and proper clinical application of AF.

Analysis of Forty-Two Psychoactive Substances in a Single Hair by Micro-Segmental Technique.

OBJECTIVES: To establish an LC-MS/MS method based on single hair micro-segmental technique, and verify the detection of 42 psychoactive substances in 0.4 mm hair segments. METHODS: Each piece of single hair was cut into 0.4 mm segments and extracted by sonication and the segments were immersed in dithiothreitol-containing extraction medium. Mobile phase A was the aqueous solution containing 20 mmol/L ammonium acetate, 0.1% formic acid, and 5% acetonitrile. Mobile phase B was acetonitrile. An electrospray ionization source in positive ion mode was used for data acquisition in multiple reaction monitoring (MRM) mode. RESULTS: The 42 psychoactive substances in hair had a good linear relationship within their respective linear ranges (r>0.99), the limits of detection were 0.2-10 pg/mm, the limits of quantification were 0.5-20 pg/mm, the intra-day and inter-day precisions were 1.5%-12.7%, the intra-day and inter-day accuracies were 86.5%-109.2%, the recovery rates were 68.1%-98.2%, and the matrix effects were 71.3%-111.7%. The method was applied to hair samples collected from one volunteer at 28 d after a single dose of zolpidem, with zolpidem detected in 5 hairs was 1.08-1.60 cm near the root tip, and the concentration range was 0.62-20.5 pg/mm. CONCLUSIONS: The micro-segmental technique of single hair analysis can be applied to the investigation of drug-facilitated sexual assault cases.

Characterizing the semantic features of climate change misinformation on Chinese social media.

Climate change misinformation leads to significant adverse impacts and has become a global concern. Identifying misinformation and investigating its characteristics are of great importance to counteract misinformation. Therefore, this study aims to characterize the semantic features (frames and authority references) of climate change misinformation in the context of Chinese social media. Posts concerning climate change were collected from Weibo between January 2010 and December 2020. First, veracity, frames, and authority references were manually labeled. Then, we applied logistic regression to examine the relationship between information veracity and semantic features. The results revealed that posts concerning environmental and health impact and science and technology were more likely to be misinformation. Moreover, posts referencing non-specific authority sources are more likely to be misinformed than posts making no references to any authority references. This study provides a theoretical understanding of the semantic characteristics of climate change misinformation and practical suggestions for combating them.

Micro-segmental analysis of the entry pathway and distribution of zolpidem in hair from different scalp regions after a single dose.

Introduction: Hair testing is well established for the assessment of past drug exposure; however, more research is needed to understand drug incorporation mechanisms and drug entry pathways into hair. Method: In this study, a micro-segmental LC-MS/MS method was used to analyze a 0.4 mm segment of hair after a single oral administration of zolpidem. Five single hairs were plucked at 1 day, 3 days, 7 days, and 28 days after administration from the vertex posterior of three subjects, and 5 single hairs were also plucked from the parietal, left temporal, and right temporal regions of the head at 28 days. Results and discussion: Proximal S1 (0-0.4 mm) in hair plucked at 1 day had the highest level of zolpidem at 1.5-2.4 pg/mm; much lower concentrations (< 1 pg/mm) were detected at proximal S2-S8 (0.4-3.2 mm). The drug concentration decreased gradually in S1 for 7 days after drug intake and disappeared by 28 days, suggesting that the drug from the bloodstream initially combined with the hair follicle and then gradually moved to the hair tip as the hair grew. The zolpidem concentration-hair segment profiles exhibited a large peak (root side) and a small peak (tip side) for the four sampling times in all three subjects, indicating that drug incorporation in the hair bulb occurred mainly from the blood but probably also entered the hair through sweat and sebum. Zolpidem was also detected in all hairs from the vertex posterior in all three subjects but was not detected in 1 hair from the parietal region and 2 hairs from the left temporal region. The consistency in drug detection, drug concentration level, and peak position was better in hair from the vertex posterior than from the other three regions, indicating that the vertex posterior is a suitable sampling region for estimating drug intake.

Determination of 5 synthetic cannabinoids in hair by Segmental analysis using UHPLC-MS/MS and its application to eight polydrug abuse cases.

In recent years, an increasing number of new synthetic cannabinoids (SCs) have appeared in the drug trade market. A UPLC-MS/MS method was developed to simultaneously identify five synthetic cannabinoids in 1 cm segment hair samples. The method was fully validated and confirmed to have good selectivity, accuracy, and precision, as well as satisfactory linearity within the calibrated range. The limit of quantification (LOD) was 0.5 pg/mg, and the lower limit of quantitation (LLOQ) was 1 pg/mg, with intraday and interday accuracies (bias) ranging from - 9.6-13.7%. The validated method was successfully used for qualitative and quantitative analysis of five SCs in authentic hair samples of eight SC abusers. SCs were detected in 8 cases at concentrations ranging from 1.5 to 632.9 pg/mg.

Natural or artificial: An example of topographic spatial distribution analysis of mescaline in cactus plants by matrix-assisted laser desorption/ionization mass spectrometry imaging.

Introduction: Differentiating whether plant products are natural or artificial is of great importance in many practical fields, including forensic science, food safety, cosmetics, and fast-moving consumer goods. Information about the topographic distribution of compounds is an important criterion for answering this question. However, of equal importance is the likelihood that topographic spatial distribution information may provide important and valuable information for molecular mechanism study. Methods: In this study, we took mescaline, a substance with hallucinogenic properties in cacti of the species Trichocereus pachanoi and Lophophora williamsii, as an example to characterize the spatial distribution of mescaline in plants and flowers by liquid chromatograph-mass spectrometry-matrix-assisted laser desorption/ionization mass spectrometry imaging at the macroscopic, tissue structure, and even cellular levels. Results: According to our results, the distribution of mescaline in natural plant was concentrated on the active meristems, epidermal tissues, and protruding parts of Trichocereus pachanoi and Lophophora williamsii, while artificially spiked Lophophora diffusa products showed no such difference in their topographic spatial distribution. Discussion: This difference in distribution pattern allowed us to distinguish between flowers that could synthesize mescaline on their own and those that had been artificially spiked with mescaline. The interesting topographic spatial distribution results, such as the overlap of the mescaline distribution map and micrographs of the vascular bundles, were consistent with the synthesis and transport theory of mescaline, indicating the potential for applying matrix-assisted laser desorption/ionization mass spectrometry imaging in botanical research.

Pulverization Is a Crucial Step-A Comparative Study of Different Pretreatments in Hair Drug Testing.

In forensic toxicology, hair has become a hot biological material for drug testing due to its wider detection window and noninvasive sampling process compared to traditional liquid biological materials (e.g., blood and urine). However, hair as a matrix differs from body fluids, as it is not as easily aliquoted for analysis. Nevertheless, pretreatment methods for hair detection have gradually improved from the first chemical methods, such as alkali digestion and acid hydrolysis, to now include the physical method of pulverization and further improvements beyond "pulverization" protocols. In a previous study, we updated and developed a "micropulverized extraction" method. In the present study, our aim was to gain a more complete understanding of the "micropulverized extraction" method by comparing pulverization temperature and hair particle size, as these two factors are known to influence the effectiveness of sample processing. The analytes we selected were those commonly encountered in traditional drug abuse cases: (±)-methamphetamine, (±)-amphetamine, morphine, 6-acetylmorphine, cocaine, benzoylecgonine, (--)-∆9-tetrahydrocannabinol, ketamine, (±)-norketamine and (±)-3,4-methylenedioxymethamphetamine. The analysis method was liquid chromatography-tandem mass spectrometry.

LC-MS-MS Determination of 88 Psychotropic Drugs in 1,865 Hair Samples from Addicts in Drug Abstinence.

The emergence of novel drugs and the continuous expansion of the scope of the types of drugs under control have greatly increased requests for screening of a range of drugs in hair. Here, a multi-analyte method for the detection and quantification of 88 psychotropic drugs in the hair of addicts in drug abstinence was developed and fully validated using liquid chromatography-tandem mass spectrometry (LC-MS-MS). Hair samples (25 mg) were washed, cut into pieces, cryogenically ground and extracted in methanol. The extracted analytes were separated on an Allure PFP Propyl column (100 × 2.1 mm, 5 mm inside diameter, Restek, USA) and analyzed by LC-MS-MS in multiple reaction monitoring modes. The limits of detection and the limits of quantification ranged from 0.1 to 20 pg/mg and 0.2 to 50 pg/mg, respectively. The intra- and inter-assay precisions (relative standard deviation (RSD)) of all analyses ranged from 0.9% to 14.9% and 1.9% to 15.9%, respectively. Accuracy values were 100 ± 20%. The extraction recovery of quality control samples ranged from 50.9% to 99.6% for all analytes. The matrix effects for all analytes ranged from 46.8% to 99.7%. The method was successfully used to analyze 1,865 hair samples from addicts in drug rehabilitation at their own communities. Among the samples, 129 cases were positive; the majority of positive cases were from males (78.29%), 92.25% of whom were >35 years old. Traditional drugs, like methamphetamine and opioids, accounted for most positive cases, and 27 of the abstinence cases with a use history of methamphetamine were still positive. In addition to abused drugs, like methamphetamine, morphine and cocaine, the sedative-hypnotic and psychotherapeutic drugs, including clonazepam, alprazolam, estazolam, zolpidem and quetiapine, were detected in 26% of the hair samples, suggesting that these addicts may have insomnia and mental problems such as depression and psychosis, probably due to the long-term effects of drugs and withdrawal reactions. Three synthetic cannabinoids were also detected in four (2.7%) cases. A total of 37 cases were positive for methadone, tramadol and dextromethorphan, reflecting a new trend of alternative drug use when traditional drugs were not easy to obtain during the coronavirus disease 2019 outbreak.

Chiral analysis of dextromethorphan and levomethorphan in human hair by liquid chromatography-tandem mass spectrometry.

PURPOSE: Methorphan exists in two enantiomeric forms including dextromethorphan and levomethorphan. Dextromethorphan is an over-the-counter antitussive drug, whereas levomethorphan is strictly controlled as a narcotic drug. Chiral analysis of methorphan could, therefore, assist clinicians and forensic experts in differentiating between illicit and therapeutic use and in tracing the source of the drug. METHODS: A method for enantiomeric separation and quantification of levomethorphan and dextromethorphan in human hair was developed and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Hair was extracted in hydrochloric acid/methanol (1:20, v/v). The supernatant were separated using a Supelco Astec Chirobiotic™ V2 column (250 × 2.1 mm, i.d., 5 µm particle size) and analyzed on a triple quadrupole linear ion trap mass spectrometer in multiple reaction monitoring mode. RESULTS: The limits of detection for dextromethorphan and levomethorphan were 2 and 1 pg/mg, respectively; the lower limit of quantification was 2 pg/mg for both drugs. Good linearity (r > 0.995) was observed for both analytes over the linear range. Precision values were below 10% for both analytes; accuracy values ranged from 87.5 to 101%. The extraction recoveries were 78.3-98.4%, and matrix effects were 70.5-88.6%. This method was applied to human hair samples from 120 people suspected of methorphan use to further distinguish the drug chirality. Dextromethorphan was detected in all 120 samples at a concentration range of 2.7-19,100 pg/mg, whereas levomethorphan was not detected in any sample. CONCLUSIONS: A sensitive quantitative method was established for the enantiomeric separation of dextromethorphan and levomethorphan in hair. This is the first study to achieve chiral analysis of methorphan in human hair.

Two DFSA cases involving midazolam clarified by the micro-segmental hair analyses.

PURPOSE: In this study, an analytical procedure to identify trace amounts of drug in hair based on micro-segmental hair analysis was presented. The method also can be used to estimate the time of drug ingestion at daily precision by cutting a single hair into sub-millimeter segments which correspond to daily hair growth. METHODS: A method was established for efficient extraction of midazolam, one of the most frequently detected compound in drug-facilitated sexual assault (DFSA) cases, from each 0.4-mm hair segment and validated by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). Moreover, two DFSA cases were used to compare the micro-segmental hair analysis with the 1- cm segmental analysis method. RESULTS: The validation showed a lower limit of quantification of 0.5 pg/mm for midazolam, with intraday and interday accuracies (bias) from - 5.2 to 0.9%. The micro-segmental hair analysis method was applied to proximal 1-cm hair segment including hair bulbs in two DFSA cases. The micro-segmental hair analysis results in case 1 showed midazolam in the S15-S17 (5.6-6.8 mm from hair bulb) in a concentration range from 0.5 to 0.9 pg/mm, and the concentrations of midazolam in all hair micro-segments (0-1 cm from the scalp) in case 2 were from 0.5 to 2.0 pg/mm. CONCLUSIONS: Comparison with the conventional method revealed that micro-segmental hair analysis may enhance the utility of hair drug testing and strengthen probative force in DFSA cases.

Establishment of a genetic transformation system for Codonopsis pilosula callus.

Codonopsis pilosula, a traditional Chinese medicinal and edible plant, contains several bioactive components. However, the biosynthetic mechanism is unclear because of the difficulties associated with functional gene analysis. Therefore, it is important to establish an efficient genetic transformation system for gene function analysis. In this study, we established a highly efficient Agrobacterium-mediated callus genetic transformation system for C. pilosula using stems as explants. After being pre-cultured for 3 days, the explants were infected with Agrobacterium tumefaciens strain GV3101 harboring pCAMBIA1381-35S::GUS at an OD600 value of 0.3 for 15 min, followed by co-cultivation on MS induction medium for 1 day and delayed cultivation on medium supplemented with 250 mg l-1 cefotaxime sodium for 12 days. The transformed calli were selected on screening medium supplemented with 250 mg l-1 cefotaxime sodium and 2.0 mg l-1 hygromycin and further confirmed by PCR amplification of the GUS gene and histochemical GUS assay. Based on the optimal protocol, the induction and transformation efficiency of calli reached a maximum of 91.07%. The establishment of a genetic transformation system for C. pilosula calli lays the foundation for the functional analysis of genes related to bioactive components through genetic engineering technology.

Time course of estazolam in single-strand hair based on micro-segmental analysis after controlled oral administration.

The mechanism of estazolam incorporation into hair was investigated by studying the time course of estazolam along single-strand hair after two oral administration of estazolam at 28 days interval. Estazolam in single hair segments 0.4 mm in length was verified and quantified by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). The distributions of estazolam within a strand of hair (collected at 12 h, 28 days, and 56 days post-administration) were visualized by micro-segmental analysis. The highest estazolam concentration (1.5-9.9 pg/mm) was detected in the hair bulb region (S1), and it then decreased through the hair shaft to the distal end, with a small fluctuation (0.3-3 pg/mm) near the junction of the hair roots and shafts (S4-S7) 12 h after drug intake. These findings suggested that the incorporation of estazolam occurred in two regions, mainly in the hair bulb and to a lesser extent in the upper dermis zone. Models using internal temporal markers (TIMs) and temporal intervals (TIs) were constructed to estimate the day of estazolam ingestion. The estimation accuracy was within an average error of 1.7 mm and 3.0 mm between the calculated and actual positions, based on the TIMs and TIs 56 days after estazolam intake. These findings can help in further elucidation of the drug incorporation mechanism, which is crucial for interpreting hair analysis results used to reveal individual drug-use history.

The chromosome-level genome of female ginseng (Angelica sinensis) provides insights into molecular mechanisms and evolution of coumarin biosynthesis.

Coumarins are natural products with important medicinal values, and include simple coumarins, furanocoumarins and pyranocoumarins. Female ginseng (Angelica sinensis) is a renowned herb with abundant coumarins, originated in China and known for the treatment of female ailments for thousands of years. The molecular basis of simple coumarin biosynthesis in A. sinensis and the evolutionary history of the genes involved in furanocoumarin biosynthesis are largely unknown. Here, we generated the first chromosome-scale genome of A. sinensis. It has a genome size of 2.37 Gb, which was generated by combining PacBio and Hi-C sequencing technologies. The genome was predicted to contain 43 202 protein-coding genes dispersed mainly on 11 pseudochromosomes. We not only provided evidence for whole-genome duplication (WGD) specifically occurring in the Apioideae subfamily, but also demonstrated the vital role of tandem duplication for phenylpropanoid biosynthesis in A. sinensis. Combined analyses of transcriptomic and metabolomic data revealed key genes and candidate transcription factors regulating simple coumarin biosynthesis. Furthermore, phylogenomic synteny network analyses suggested prenyltransferase genes involved in furanocoumarin biosynthesis evolved independently in the Moraceae, Fabaceae, Rutaceae and Apiaceae after ζ and ε WGD. Our work sheds light on coumarin biosynthesis, and provides a benchmark for accelerating genetic research and molecular breeding in A. sinensis.

Comparison of public discussions of gene editing on social media between the United States and China.

The world's first gene-edited babies event has stirred controversy on social media over the use of gene editing technology. Understanding public discussions about this controversy will provide important insights about opinions of science and facilitate informed policy decisions. This study compares public discussion topics about gene editing on Twitter and Weibo, as wel asthe evolution of these topics over four months. Latent Dirichlet allocation (LDA) was used to generate topics for 11,244 Weibo posts and 57,525 tweets from September 25, 2018, to January 25, 2019. Results showed a difference between the topics on Twitter versus Weibo: there were more nuanced discussions on Twitter, and the discussed topics between platforms focused on different areas. Temporal analysis showed that most discussions took place around gene-edited events. Based on our findings, suggestions were provided for policymakers and science communication practitioners to develop more effective communication strategies toward audiences in China and the U.S.

Microblog credibility indicators regarding misinformation of genetically modified food on Weibo.

The considerable amount of misinformation on social media regarding genetically modified (GM) food will not only hinder public understanding but also mislead the public to make unreasoned decisions. This study discovered a new mechanism of misinformation diffusion in the case of GM food and applied a framework of supervised machine learning to identify effective credibility indicators for the misinformation prediction of GM food. Main indicators are proposed, including user identities involved in spreading information, linguistic styles, and propagation dynamics. Results show that linguistic styles, including sentiment and topics, have the dominant predictive power. In addition, among the user identities, engagement, and extroversion are effective predictors, while reputation has almost no predictive power in this study. Finally, we provide strategies that readers should be aware of when assessing the credibility of online posts and suggest improvements that Weibo can use to avoid rumormongering and enhance the science communication of GM food.

Pharmacokinetic study of midazolam and α-hydroxymidazolam in guinea pig blood and hair roots after a single dose of midazolam.

The appearance of midazolam (M) and its metabolites into the hair root following a single administration was examined by following the time course of M and α-hydroxymidazolam (αHM) in hair roots and blood from guinea pigs. The back hair of guinea pigs was shaved before drug administration and before each sampling, and hair roots (3-5 mm) were plucked at 5, 15, and 30 min, 1, 2, 4, 6, 10, 24, 48, 72, 96, 120, 144 h, and 7, 14, 21, and 28 days. The kinetic parameters of M and αHM in guinea pig blood and hair roots were determined for three doses (5, 10, and 25 mg/kg). Comparisons of drug time course between hair roots and blood indicated an association between drug concentrations in the hair root and the blood. M and αHM entered the hair root within 5 min after a single exposure. The detection windows were also longer for the hair root than for the blood. Consequently, the hair root can be a valuable specimen in acute poisonings or drug-facilitated crime (DFC) cases, if other matrices are unavailable, or if blood and urine results are negative. Hair shafts (with hair roots) were plucked at 28 days and segmented. The concentrations of M and αHM were lower in the hair shafts than in the hair roots. The concentrations of the metabolite αHM in hair shafts were barely detectable. The concentrations of M and αHM in the hair root showed a moderate correlation with dose. Comparison of drug levels in hair roots between the washed group and the unwashed group indicated a generally stable percentage between the washed and unwashed groups of 40-60 % during the entire time course. This indicates that drugs are likely to be immobilized in the hair root at the beginning of the incorporation process.